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Hip osteoarthritis

107 citationsUpdated Sep 2026

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Overview

Hip osteoarthritis is a prevalent condition that places significant demands on health services [4]. Clinical disease severity varies widely at the time of total hip replacement [5], and in advanced cases, clinical severity shows no correlation with radiographic severity [5]. The condition affects diverse patient populations; approximately 22% of young patients undergoing hip arthroscopy receive a clinical diagnosis of hip osteoarthritis within 2 years [3]. Additionally, multimorbid lumbar spinal stenosis co-occurs with hip osteoarthritis in people at a rate of 0 to 54% [33]. In hips with femoroacetabular impingement without surgical intervention, 14% developed symptomatic osteoarthritis and 4% underwent total hip arthroplasty at a mean follow-up of 24.7 years [7].

Total hip arthroplasty results in patients performing physically better than untreated patients with advanced hip osteoarthritis [26], although long-term self-reported physical quality of life and hip functionality remain impaired [26]. For specific populations, such as those with developmental hip dysplasia, deficient anterolateral acetabular coverage causes structural instability and acetabular rim overload [185]. The long-term prognosis for symptomatic moderate dysplasia (lateral center-edge angle <15°) treated nonsurgically is very poor [185]. The Bernese periacetabular osteotomy offers a 60% survival rate at 20-year follow-up [185], with delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) assessment of glycosaminoglycan content predicting outcome; low content is associated with increased risk of failure [185].

Hip arthrodesis is uncommonly used for advanced hip degeneration, often posttraumatic, in a very specific patient population [19]. Indications include being younger than 30 years, high activity level, severe pain and stiffness, and normal adjacent joints [19]. Contraindications include disease of the adjacent joints, major limb-length discrepancy greater than 2.0 cm, and active infection [19]. The preferred position is 25° to 30° of hip flexion, 0° to 5° of adduction, and 5° to 10° of external rotation [19]. While hip arthrodesis achieves lasting pain relief and satisfactory clinical results in most patients [19], survivorship can be limited by symptomatic degenerative disease of the adjacent joints, including the lumbar spine, contralateral hip, and ipsilateral knee [19]. Low back pain and osteoarthritis of the ipsilateral knee are the most common problems following hip arthrodesis [19], and conversion to total hip arthroplasty is occasionally needed [19].

Anatomy & Pathophysiology

Bony Anatomy

The hip is a multiaxial joint formed by the articulation between the pelvis and femur, connecting the axial skeleton and the lower extremity [92]. The hemipelvis comprises three bones—the ilium, ischium, and pubis—which unite at the triradiate cartilage within the concave acetabulum [92]. The acetabulum consists of an articular crescent-moon–shaped lunate surface and a nonarticular central fossa that serves as the attachment point for the ligamentum teres [92]. Inferiorly, the acetabulum is incomplete, forming a notch through which vital blood vessels and nerves pass to supply the joint [92]. The femoral head forms two-thirds of a sphere, featuring a small central depression from which the ligamentum teres extends to connect to the acetabular notch [92].

The neck-shaft angle of the femur averages 125° [92], with a mean adult value of 130° ± 7° [99]. Normal version, defined as the head-neck angle in the frontal plane, averages 15 to 20° [92], while the mean anteversion of the femoral neck is 10° ± 7° [99]. The proximal femur contains two prime trabecular groups: the principal tensile group and the principal compressive group [99]. The weakest area in the femoral neck is located in the Ward triangle [99]. The calcar femorale, a medial area of dense trabecular bone, transfers stress from the femoral shaft to the inferior portion of the femoral neck [99].

Soft Tissue Anatomy

The acetabular labrum is a fibrocartilaginous ring attached to the rim of the acetabulum that extends the articulating surface area and increases femoral head coverage [92]. Triangular in cross section, the labrum contributes to creating a pressurized seal of the central compartment of the hip during loading [92]. Only the external one-third of the labrum contains blood vessels, leaving the majority of the structure avascular and limiting its healing ability following injury [92]. The labrum is highly innervated, containing both mechanoreceptors and nociceptors [92]. It is absent in the area of the inferior acetabular notch, where the transverse acetabular ligament serves as its continuation [92].

The hip is surrounded by a dense fibrous capsule extending from the periphery of the acetabulum to the intertrochanteric line of the femoral neck [92]. The capsule attaches anteriorly and posteriorly along the periphery of the acetabulum outside the labrum [94]. On the femur, the capsule attaches anteriorly along the intertrochanteric crest, while on the posterior side it attaches only partially, leaving the basicervical region of the femoral neck and intertrochanteric region extracapsular [94]. Three main ligaments support the hip: * Iliofemoral ligament: Y-shaped and the thickest and strongest of the three, it functions to limit external rotation, while its lateral arm limits extension of the joint [92]. It becomes taut in full extension, preventing anterior dislocation and hyperextension [94]. * Ischiofemoral ligament: Extends from the ischial margin of the acetabulum to the greater trochanter and restricts internal rotation motion [92]. * Pubofemoral ligament: Extends from the obturator crest of the pubic bone to the femoral neck and acts to limit abduction of the joint [92].

Deep fibers from the iliofemoral, ischiofemoral, and pubofemoral ligaments merge to form the zona orbicularis [92]. The twisted orientation of these hip ligaments provides a screw mechanism for the hip in full extension [94]. The ligamentum teres originates in the cotyloid fossa and attaches on the fovea of the femoral head [94].

Muscular Anatomy

The average range of motion of a normal hip is approximately 120° of flexion, 30° of extension, 45° of abduction, 20° to 30° of adduction, 35° of internal rotation, and 45° of external rotation [98]. Normal gait function requires hip flexion of 30°, hyperextension of 10°, abduction and adduction of 5°, and internal and external rotation of 5° [98]. The primary hip flexor muscles are the iliopsoas, rectus femoris, and sartorius [98]. The gluteus maximus and hamstring muscles are the most important hip joint extensors [98]. The abductors of the hip are predominantly the gluteus medius and minimus muscles, which function together to maintain and abduct the femur during the stance phase of gait [98]. A Trendelenburg lurch is an attempt by the body to compensate for abductor weakness by bringing the center of gravity closer to the hip center [98]. The external rotators include the obturator internus and externus, superior and inferior gemelli, quadratus femoris, and piriformis muscles [98]. The most consistent internal rotators are the gluteus medius and tensor fascia latae muscles [98].

Vascular Anatomy

In adulthood, the major blood supply to the femoral head is from the medial femoral circumflex and lateral epiphyseal arteries [102]. From birth to approximately 4 years of age, the major blood supply comes from the medial and lateral femoral circumflex arteries, with major contributions from the artery of the ligamentum teres [102]. From the age of 4 years to adulthood, the posterosuperior and posteroinferior retinacular arteries (from the medial circumflex artery) are the major blood supply to the femoral head [102]. The medial femoral circumflex artery is the main blood supply to the femoral head and terminates in the posterior aspect of the extracapsular arterial ring [99]. The lateral femoral circumflex artery gives rise to the anterior aspect of the extracapsular arterial ring [99].

The ascending cervical arteries originate from the extracapsular arterial ring and are divided into four distinct groups: lateral, medial, posterior, and anterior [99]. The lateral group of ascending branches is the main blood supply to the femoral head [99]. The lateral epiphyseal artery penetrates the femoral head and is believed to be the dominant blood supply to the femoral head from the ascending branch system [99]. Fractures that disrupt the ascending blood flow to the lateral epiphyseal vessel have an increased risk of osteonecrosis [99]. The artery of the ligamentum teres arises from either the obturator or medial femoral circumflex artery and does not provide sufficient blood supply to maintain the viability of the femoral head [99].

Pathophysiology

The primary changes of hip osteoarthritis include loss of articular cartilage, remodeling of subchondral bone, and formation of osteophytes [65]. The disease process usually involves all tissues that form the synovial joint, including the articular cartilage, subchondral bone, metaphyseal bone, synovium, ligaments, joint capsule, and muscles crossing the joint [65]. Despite its name implying an inflammatory process, inflammation is not a major component of osteoarthritis in most patients [65]. The etiology of hip osteoarthritis is multifactorial [65]. On a cellular level, osteoarthritis appears to be the result of deterioration in the ability of chondrocytes to maintain and restore articular cartilage [65]. Chondrocytes undergo age-related telomere erosion and increased expression of the senescence marker β-galactosidase, indicating that cell senescence is responsible for the age-related loss of chondrocyte function [65].

Subtle morphologic abnormalities around the hip, such as femoroacetabular impingement and acetabular dysplasia, may contribute to a mechanical process that results in articular cartilage damage and end-stage hip arthrosis [65]. Femoroacetabular impingement is abnormal bony contact between the rim of the acetabulum and the proximal femur during hip motion that can cause pain and damage to the acetabular labrum and articular cartilage [65]. * Cam impingement: Occurs when excessive bone is present at the junction of the femoral head and neck, resulting in decreased offset at the head-neck junction [65]. Cam morphology primarily develops during adolescence and is strongly associated with athletic activity during this period [38]. Cam morphology has been associated with the development of hip osteoarthritis [54]. * Pincer impingement: Occurs when excessive bone is present along the rim of the acetabulum from an excessively deep socket or acetabular retroversion [65]. The association between pincer morphology and hip osteoarthritis is much less clear [54], although severe pincer morphology is associated with incident hip osteoarthritis [194]. * Mixed impingement: Many cases of femoroacetabular impingement involve a combination of cam and pincer impingement [65].

Increasing evidence suggests that femoroacetabular impingement may be a major contributing factor to the development of hip osteoarthritis in many cases [65]. Femoroacetabular impingement syndrome in middle-aged individuals is strongly associated with the development of hip osteoarthritis within 10-year follow-up [36]. Acetabular dysplasia describes a shallow hip socket without frank dislocation of the femoral head but with varied degrees of superior lateral subluxation [65]. The shallow hip socket in acetabular dysplasia results in high articular cartilage contact stresses near the superolateral rim of the acetabulum, with concurrent labral tears and progressive lateral subluxation of the femoral head [65].

When there is loss of sphericity in the ball-and-socket joint, the articular surface is exposed to abnormal loads and contact forces leading to hyaline cartilage damage [155]. Common mechanical causes of hip osteoarthritis include developmental dysplasia of the hip (under-coverage), femoroacetabular impingement (over-coverage), and long-term consequences of Legg-Calvé-Perthes disease and slipped capital femoral epiphysis [155]. In post-traumatic osteoarthritis, there is loss of congruency of the articulating surface [155]. Non-mechanical causes of hip osteoarthritis include avascular necrosis of the femoral head, ankylosing spondylitis, inflammatory arthritis, and primary disorders of cartilage and the synovium [155]. Hip microinstability refers to the femoral head micromotion within the acetabulum, which is a prolonged phenomenon that leads to cartilage damage and eventually osteoarthritis of the hip [103]. Distinct transcriptome profiles for early and late stage hip degeneration have been identified along with key molecular contributors to the progression of hip osteoarthritis [87].

In a 2017 study of 162 patients aged 55 years and older, the probability of undergoing total hip arthroplasty in 10 years based on hip morphology was approximately one in three for dysplasia of the hip and one in five for both femoroacetabular impingement and normal morphology hips [70]. In the same study, the approximate probability of undergoing total hip arthroplasty at 20 years was two in three for dysplasia of the hip and one in two for both femoroacetabular impingement and normal morphology hips [70]. Radiographic variables with negative prognostic value for hip osteoarthritis progression include femoral head lateralization greater than 8 mm, femoral head extrusion index greater than 0.2, acetabular depth-to-width index less than 0.3, lateral center-edge angle less than 25°, and Tönnis angle greater than 8° [70]. Reduced joint space, low center-edge angle, low head to neck ratio, and osteophytes are associated with the development of osteoarthritis over an average 11-year radiographic follow-up period [70]. In a 2016 study of 367 patients undergoing total hip arthroplasty with no contralateral hip symptoms, Kaplan-Meier survivorship estimated that 41% of these patients develop symptoms at 10 years and 19% went on to total hip arthroplasty [70].

Posttraumatic osteoarthritis can amount to 12% of symptomatic hip osteoarthritis [70]. In a review of 30 traumatic hip dislocations, those characterized as complex were more likely to develop osteoarthritis (4/9, 44%) or osteonecrosis (3/9, 33%) [70]. Retention of any intra-articular fragments following traumatic hip dislocation is associated with the development of posttraumatic osteoarthritis [70]. Rapidly progressive osteoarthritis of the hip is uncommon, more common in elderly women, and may be associated with intra-articular corticosteroid injections [70]. A 2018 study found a 21% rate of rapidly progressive osteoarthritis in patients who receive hip injections [70].

Individuals with mild-to-moderate hip osteoarthritis have lower limb muscle strength and volume deficits [27]. Early interventions to target muscle weakness and prevent the development of strength asymmetries that are characteristic of advanced hip osteoarthritis appear warranted [27]. Greater cross-sectional area of hip flexors might be associated with better quality of life in individuals with mild-to-moderate hip osteoarthritis [188]. Segmental electrical bioimpedance equipment can detect differences between limbs affected and unaffected by hip osteoarthritis [177]. Reduced gait velocity, reduced sagittal plane joint excursion, and a reduced hip flexion moment in the late stance phase of gait are evident in hip osteoarthritis patients with mild to moderate symptoms [123]. Subjects with end-stage hip osteoarthritis had 3.49 degrees less peak hip flexion and 8.82 degrees less extension angles [139]. Prior to total hip arthroplasty, individuals with hip osteoarthritis presented with an increased contralateral shift and forward displacement of the center of mass [48]. The reduced ability of flexion in the arthritic hip leads to posterior pelvic tilt in the relaxed-seated position, associated with compensatory increased lumbar flexion [151]. Spinal alignment and mobility should be considered when assessing risk and designing preventive intervention for radiographic progression of secondary hip osteoarthritis [77]. In patients with excessive hip adduction and pelvic tilt toward the swing limb during gait, gait modification may contribute to the reduction of hip joint loading [147]. The reversal gait profile is associated with hip osteoarthritis risk [51]. Only upper body motion provided nonredundant and sensitive parameters representing gait adaptations in individuals with hip osteoarthritis [117]. There was no main effect of radiographic disease severity on hip kinematic variability in the sagittal or frontal plane in hip osteoarthritis [116]. Patients with hip osteoarthritis showed the poorest repeatability between gait recordings collected by different examiners, as compared to patients operated with a total hip arthroplasty and healthy controls [140].

The incidence of depression among hip replacement patients in California between 2007 and 2010 increased 20%, affecting about 9% of patients [52]. A 2018 study examining sleep patterns for patients with osteoarthritis found 53% had insomnia symptoms and 66% had obstructive sleep apnea [52]. Pain and depression were associated with insomnia, while opioid use and depression were associated with obstructive sleep apnea in patients with osteoarthritis [52]. The duration of sleep is strongly inversely correlated with osteoarthritis symptoms [52]. The effect of opioids in treating arthritis pain and improving function was minimal and did not outweigh the risk of adverse events or side effects according to a 2014 Cochrane review [52]. A 2018 randomized controlled trial comparing opioids to nonopioids showed no difference in function and worse pain intensity for the opioid group [52]. Preoperative opioids correlate with higher postoperative narcotic usage and more difficult-to-control perioperative pain [52].

Classification

Radiographic Grading Systems

Kellgren-Lawrence: This 4-point grading system is widely recommended as a reliable radiologic classification for the hip based on reliability data between radiologists and orthopaedic surgeons [81]. It ranges from Grade 0, representing healthy hips with no features of osteoarthritis [34, 184], to Grade 4, representing end-stage OA with severely impaired joint space, cysts, and subchondral sclerosis [34, 184]. Intermediate grades include Grade 1 (doubtful: questionable osteophytes or joint space narrowing) [22, 184], Grade 2 (minimal: definitive small osteophytes, little or mild joint space narrowing) [22, 184], and Grade 3 (moderate: definitive moderate osteophytes, joint space narrowing ≥50%) [22, 184].

Tönnis: This 3-point grading system categorizes hip osteoarthritis into mild, moderate, and severe stages [22]. Grade 0 demonstrates normal joint space with no arthritic changes [74]. Grade 1 shows slight joint space narrowing, increasing subchondral sclerosis of the acetabulum and/or femoral head, and mild osteophyte formation [74]. Grade 2 shows small cysts in the head or acetabulum, moderate joint-space narrowing, and moderate loss of sphericity of the femoral head [74]. Grade 3 demonstrates large cysts in the femoral head or acetabulum, severe joint-space narrowing or obliteration, and severe deformity of the femoral head [74].

Conventional radiographs remain critical in the initial imaging evaluation and diagnosis of hip osteoarthritis [22]. A complete hip series usually consists of an anterior-posterior (AP) pelvis, a centered AP hip, a lateral view (frog-leg, cross-table, Dunn 45° or 90°), and a false-profile (Lequesne) view [22]. The Kellgren-Lawrence and Tönnis classifications are more often used in the research setting than the clinical setting [22]. Radiographic and clinical severity do not necessarily correlate, particularly if radiographs are non-weight-bearing or if false-profile views are not included [22].

Clinical and Radiographic Discrepancy

In advanced hip OA, clinical severity shows no correlation with radiographic severity [5]. The benefits of hip arthroscopy for patients with Tönnis grade 2 or greater hip osteoarthritis are ambiguous due to contradictory research and varying reliability of the Tönnis classification [136]. No evidence exists on outcomes following non-operative management of FAI with concomitant Tönnis Grade 2 or more OA of the hip [31].

Staging and Phenotyping

Future clinical trials investigating the natural history and treatment of femoroacetabular impingement will require multimodal staging systems for hip osteoarthritis [9]. The optimal staging system for hip osteoarthritis will differ based on the size of the study population, the specific objective in question, and the time frame in which the investigator expects to see the specified end point [9]. The identification of clinical phenotypes and prognostic factors for outcomes in pain and disability is a step towards pre- and postoperative precision medicine for individuals with hip OA undergoing THA [25]. Patients with hip FAI can be separated into 5 clusters using dimension reduction and clustering algorithms, with each cluster having a different risk for OA progression [159]. Significant differences in survival to OA progression were found between specific clusters of patients with hip FAI [159].

Diagnostic Tools and Imaging

No recommendation can be made regarding the use of hip injections for diagnosing hip OA [12]. An interpretable machine learning approach using gait analysis demonstrates superior performance compared to other up-to-date methods and can serve as a supplementary tool to the KL grading scale for hip OA detection and severity assessment [47]. An artificial intelligence model using plain radiographs and clinical data performed adequately in predicting hip OA progression [53].

Clinical Presentation

History and Symptoms

Symptomatic femoroacetabular impingement (FAI) typically presents with an insidious onset or following minor trauma, characterized by activity-related groin pain exacerbated by hip flexion [23]. Patients frequently report difficulty with prolonged sitting, walking, running, or pivoting, alongside mechanical symptoms secondary to labral and articular cartilage disease [23]. Acetabular labral disease similarly manifests as groin pain worsened by these activities [19]. In a population-based sample in Denmark, knee and hip pain within the last month was frequent among individuals aged 29–59 years, with multiple known osteoarthritis risk factors associated with the presence of this pain [11]. Rapid destructive hip osteoarthritis represents an uncommon subset of arthrosis with rapid progression [14]; patients exhibiting rapidly progressive osteoarthritis before total hip arthroplasty (THA) showed worse patient-reported outcomes compared with those without rapid progression [16]. Without surgical intervention, 14% of hips developed symptomatic osteoarthritis and 4% underwent THA at a mean follow-up of 24.7 years in patients with FAI [7].

Functional and psychosocial factors significantly influence the clinical picture. Individuals with hip osteoarthritis present with an increased contralateral shift and forward displacement of the center of mass prior to THA, and functional movement compensations persist during the five times sit-to-stand test one year post-THA [48]. Comorbid lumbar spinal stenosis occurs in people with knee or hip osteoarthritis at a prevalence of 0 to 54%, and characteristics associated with lumbar spinal stenosis symptoms may help identify co-occurring conditions to guide clinical decision-making [33][10]. Early screening for depression in the disease course may contribute to better patient-reported pain, health-related quality of life, and satisfaction after future THA [44]. Socioeconomic factors, including insurance status, income, and gender, are associated with the imaging and treatments performed in managing hip and knee osteoarthritis [66]. Additionally, two-thirds of people with hip and/or knee osteoarthritis in Portugal have poor management of their pain levels [43].

Physical Examination

A thorough history is essential to differentiate between common causes of hip pain, as clinical examination tests and imaging findings must confirm a suspected diagnosis [21]. Patients with FAI exhibit restricted hip internal rotation in 90° of flexion [23]. The impingement test (flexion, adduction, internal rotation) elicits pain in FAI but is not specific for the condition [23]. Pain localization aids in distinguishing intra-articular from extra-articular pathologies. Anterior groin pain is most associated with intra-articular pathologies, including labral tears, degenerative changes, synovial pathologies, loose bodies, and osteonecrosis [180]. However, anterior groin pain can also result from extra-articular conditions such as hip flexor strains, iliopsoas snapping syndrome, or femoral stress fractures [180]. Pain along the lateral thigh is often associated with greater trochanteric bursitis, iliotibial band syndrome, or abductor tendon tears or tendinitis [180]. Posterior hip and pelvic pain may result from muscle pathologies such as piriformis syndrome and hamstring muscle tears, or from referred pain from the sacroiliac joint or low back [180]. Range of motion and muscle strength measurements in patients with hip osteoarthritis have been evaluated for reproducibility in inter-rater studies [108].

Imaging and Diagnostic Assessment

Conventional radiographs remain critical in the initial imaging evaluation of the hip [22]. A complete hip series usually consists of an anterior-posterior pelvis, a centered anterior-posterior hip, a lateral view (frog-leg, cross-table, Dunn 45° or 90°), and a false-profile (Lequesne) view [22]. Osteoarthritis of the hip can be categorized using the Kellgren-Lawrence or Tönnis classifications [22]. Radiographic and clinical severity do not necessarily correlate, particularly if the radiographs are non-weight-bearing or if false-profile views are not included [22]. The femoral head-neck junction morphology is often assessed using the alpha angle on radiographs [22]. Some studies have shown that radiographs, in particular the Dunn 45° view, may be more accurate for determining the alpha angle measurement than CT or MRI [22].

Ultrasonography can assess the anterior portions of the hip, including the iliopsoas muscle, tendon, and bursa, joint capsule, acetabular labrum, portions of the femoral head articular cartilage, and bony contours of the joint [75]. Joint effusions are diagnosed on ultrasonography when fluid distends the joint capsule greater than 7 mm, or when there is a greater than 1 mm side-to-side difference between hips [75]. Ultrasonography can also assess for painful periarticular snapping of the hip attributable to internal causes (iliopsoas tendon complex) and external causes (iliotibial band over the greater trochanter) [75]. For clinical practice, no recommendation can be made regarding the use of hip injections for diagnosing hip osteoarthritis [12].

An interpretable machine learning approach for predicting and grading hip osteoarthritis using gait analysis demonstrated superior performance compared to other up-to-date methods [47]. This proposed machine learning method can serve as a supplementary tool to the Kellgren-Lawrence grading scale for hip osteoarthritis detection and severity assessment in clinical practice [47]. The Dutch Lower Extremity Functional Scale is recommended as the outcome measure of choice to assess self-reported physical functioning in individuals with hip or knee osteoarthritis [124]. Limited evidence exists on the use of patient-reported outcomes as an integrated part of clinical practice for patients with hip and knee osteoarthritis [13].

Investigations

Clinical Examination: A thorough clinical examination is required to establish a differential diagnosis for hip pain, as many hip conditions present with similar symptoms [21]. Clinical examination tests and imaging findings should be used to confirm a suspected clinical diagnosis [21]. No recommendation can be made regarding the use of anesthetic hip joint injections for diagnosing hip osteoarthritis [12]. Intra-articular corticosteroid injections provide large, clinically meaningful short-term pain relief and functional improvement in hip osteoarthritis, with benefits not reliably sustained beyond three months [15]. Viscosupplementation cannot be recommended as standard therapy in hip osteoarthritis for wider populations, and indications remain a highly individualised matter [6]. Radiological features, specifically joint space narrowing, might be of importance for the decision of viscosupplementation in patients with hip osteoarthritis [195].

Plain radiography: A complete hip series usually consists of an anterior-posterior pelvis, a centered AP hip, a lateral view (frog-leg, cross-table, Dunn 45° or 90°), and a false-profile (Lequesne) view [22]. The femoral head-neck junction morphology is often assessed using the alpha angle [22]. Kellgren-Lawrence scores 1, 2, and 3 represent mild, moderate, and moderate-severe osteoarthritis, respectively [34]. Acetabular offset can be accurately determined on conventional radiographs in patients with primary hip osteoarthritis [86]. Radiographic findings appeared to correspond with functional status in former American-style football players with knee osteoarthritis but not hip osteoarthritis [175]. An interpretable machine learning approach for predicting and grading hip osteoarthritis using gait analysis demonstrates superior performance compared to other up-to-date methods and can serve as a supplementary tool to the Kellgren-Lawrence grading scale [47]. An artificial intelligence model performed adequately in predicting hip osteoarthritis progression using plain radiographs and clinical data [53].

MRI: MRI is the modality of choice for patients suspected of soft tissue or intra-articular pathology, given its superior sensitivity and specificity [107]. Conventional MRI is effective at identifying osteochondral injuries, musculotendinous pathologies, and inflammation [107]. Magnetic resonance arthrography is more appropriate to determine injuries to the labrochondral structures and the ligamentum teres and identify the presence of loose bodies and synovial chondromatosis [107]. The utility of magnetic resonance arthrography in the accurate detection and staging of articular cartilage lesions is reduced, with sensitivity reported to be less than 50% compared with arthroscopic findings [107]. Recent advances in MRI imaging techniques, such as delayed gadolinium-enhanced MR imaging and T2 mapping, allow for a more in-depth analysis of the structure of articular cartilage [107]. Delayed gadolinium-enhanced MR imaging and T2 mapping were effective at detecting early changes to the articular cartilage surfaces of patients with hip dysplasia and femoroacetabular impingement [107]. Noncontrast 3T MRI and 1.5T magnetic resonance arthrography have similar accuracies for the evaluation of femoroacetabular impingement [111]. The accuracy of noncontrast 3T MRI for labral tears and acetabular cartilage lesions was 98% and 90%, respectively, when evaluated against hip arthroscopy [111]. Gadolinium-enhanced MRI arthrogram is useful when labral pathology is suspected, especially when associated with femoroacetabular impingement [119]. MRI may identify gluteus medius and gluteus minimus tears in patients with lateral hip pain and abductor weakness [119].

CT: CT scans are effective for examining cortical and cancellous bone and can be used to create three-dimensional reconstructions of the hip for use in surgical planning [107]. Measurements of femoral head coverage and acetabular and femoral impingement can be performed reliably using CT images [107]. Low-dose CT with three-dimensional reformats is particularly useful in surgical planning of complex or borderline deformities [23]. Three-dimensional CT with pelvic remodeling may be indicated for preoperative planning for reconstruction associated with dysplasia surgery, femoroacetabular impingement, posttraumatic arthritis, or other complex primary total hip arthroplasty [119].

Ultrasonography: Ultrasonography provides real-time dynamic assessment of the hip and is useful in diagnosing soft-tissue abnormalities about the hip joint [95]. Ultrasonography is particularly useful in providing real-time guidance during diagnostic and therapeutic procedures [95]. Although ultrasonography is a valuable tool to examine pediatric hip conditions, its utility in evaluating the adult hip is limited [107]. Ultrasonography can be an effective modality to identify musculotendinous disruptions, effusions associated with intra-articular pathology, or inflammatory conditions, such as bursitis [107]. Ultrasonography is increasingly used for targeted injections into muscles, tendons, or intra-articularly around the hip [107].

Other Considerations: Abnormal femoral anteversion is associated with the development of hip osteoarthritis [34]. Radiographic evidence of femoroacetabular impingement is common in active patients with hip complaints [60]. Spinal pathology was significantly associated with both the development and progression of hip osteoarthritis [197]. Lumbosacral fusion increases the risk of hip osteoarthritis, particularly in patients with long-segment lumbosacral fusion [42]. Sagittal alignment and mobility of the thoracolumbar spine are associated with radiographic progression of secondary hip osteoarthritis [77]. Pelvic tilt can be used to potentially improve the ability to discern hip-spine syndrome types/pathologies in a subset of patients with hip osteoarthritis and spinal sagittal malalignment [40]. Multiple known osteoarthritis risk factors were associated with the presence of knee/hip pain in individuals aged 29–59 years [11].

Treatment

Non-Operative Management

Conservative management constitutes the initial standard of care for hip osteoarthritis, prioritizing weight loss, nonopioid analgesics, activity modification, low-impact exercise, and ambulatory aids [69]. Nonsteroidal anti-inflammatory medications and acetaminophen remain the cornerstone of pharmacological treatment [52]. NSAIDs have strong evidence supporting their use in hip OA [131], whereas evidence does not support the use of glucosamine sulfate [131]. Opioid medications should not play a role in managing chronic OA symptoms, as their effect on pain and function was minimal and did not outweigh the risk of adverse events [52]. A randomized controlled trial comparing opioids to nonopioids showed no difference in function and worse pain intensity for the opioid group [52]. Preoperative opioid use correlates with higher postoperative narcotic usage and more difficult-to-control perioperative pain [52].

Intra-articular corticosteroid injections are recommended as the most efficient agent for short-term pain relief and functional improvement in hip OA [144]. These injections are safe and effective at reducing pain and improving function for up to three months, with a low risk of adverse events [61]. Benefits are not reliably sustained beyond three months [15], although efficacy in immediate and delayed pain reduction has been demonstrated within 12 weeks [72]. Evidence suggests that steroid injection is more effective than saline injection for treating hip joint pain and restoring functional outcomes [132]. The most common adverse event associated with intra-articular injection of cross-linked hyaluronic acid combined with triamcinolone hexacetonide was transient hip pain [32].

Viscosupplementation cannot be recommended as standard therapy for wider populations, and indications remain a highly individualised matter [6]. There is no strong evidence to support the use of hyaluronate in the hip, and it is not approved by the FDA for hip use in the United States [131]. Patients treated with either platelet-rich plasma (PRP) or hyaluronic acid (HA) injections can expect similarly beneficial short-term clinical outcomes [24]. However, the therapeutic effects of PRP and PRP+HA injections lasted longer (6 months), and their effects on performance, disability, and activities of daily living were superior to HA in the long run [64]. A single injection of amniotic suspension allograft is safe and effective for mild to moderate hip OA, demonstrating promising results for pain relief and improved patient-reported outcomes for up to one year [28].

Physical therapy and exercise interventions offer moderate benefits. Neuromuscular exercise had moderate effects in patients with severe hip OA [2]. A six-week physiotherapist-led exercise and education intervention resulted in sustained significant improvements in pain severity and interference in patients with hip or knee osteoarthritis awaiting arthroplasty compared with a control group [29]. In adults with severe hip OA, total hip replacement reduced hip pain and improved self-reported hip function at 6 months compared with resistance training [129]. Insufficient evidence exists to establish the effectiveness of physiotherapy exercise following primary hip replacement for osteoarthritis [196].

Additional nonoperative considerations include the use of an assist device such as a cane or crutch in the opposite hand of the affected hip [131]. Weight loss may be beneficial for pain and function in patients with hip OA [131]. Characteristics associated with comorbid lumbar spinal stenosis symptoms may help identify co-occurring conditions to guide clinical decision-making [10]. Consideration of sarcopenic obesity should be included in osteoarthritis patient assessments [68]. Nonoperative OA hip patients were generally unreceptive to using smart technologies, with the exception of smartphone applications [181].

Operative Management

Indications: Surgery is justified if, despite conservative measures, pain at rest and pain with motion and weight bearing are severe enough to prevent the patient from working or from carrying out activities of daily living [69]. Patients with limitation of motion, limp, or leg-length inequality with little or no hip pain are not candidates for total hip arthroplasty [69]. Clinical disease severity varies widely at the time of total hip replacement for osteoarthritis, and in advanced hip OA, clinical severity shows no correlation with radiographic severity [5]. Findings question whether total hip arthroplasty should be prioritized only for patients who have severe hip OA symptoms, but require confirmation in a trial [17].

Hip arthrodesis is uncommonly used but can treat advanced hip degeneration, often posttraumatic, in a very specific patient population [19]. Indications for hip arthrodesis include being younger than 30 years, having a high activity level such as manual labor, severe pain and stiffness, and normal adjacent joints including the lumbar spine, contralateral hip, and ipsilateral knee [19]. Contraindications include disease of the adjacent joints (lumbar spine, contralateral hip, ipsilateral knee), major limb-length discrepancy greater than 2.0 cm, and active infection [19]. The survivorship of hip arthrodesis can be limited by symptomatic degenerative disease of the adjacent joints, with low back pain and osteoarthritis of the ipsilateral knee being the most common problems [19]. Conversion of hip fusion to total hip arthroplasty is occasionally needed, and good clinical results are seen in most patients following this conversion [19].

For femoroacetabular impingement (FAI) with concomitant hip OA, patients with Tönnis grade 2 or greater benefit from operative management rather than nonoperative management if they are younger and/or have a normal BMI [158]. Patients with FAI and concomitant hip OA of Tönnis grade 2 or greater are poor candidates for hip preservation surgery if they have severe joint space narrowing, Tönnis grade 3 hip OA, or a bilateral location of cartilage defects [158]. Tönnis grade 3 OA should be a contraindication for hip preservation surgery [158]. No evidence exists on outcomes following non-operative management of femoroacetabular impingement with concomitant Tönnis Grade 2 or more OA of the hip [31].

Surgical Approach / Technique: Total hip arthroplasty is a reliable surgical intervention for end-stage hip arthritis and has become safer over the past decade [79]. Femoral or periacetabular osteotomy should be considered for young patients with osteoarthritis if the joint is not grossly incongruous and satisfactory motion is present [69]. Periacetabular osteotomy in patients with dysplasia may decrease the need for structural bone grafting if later conversion to arthroplasty is needed [69]. If an osteotomy relieves symptoms for 10 years or more, and then an arthroplasty is required, the patient will have been able to engage in more physical activity, bone stock will have been preserved, and the patient will be older and less physically active [69].

Hip arthroscopy in the setting of hip OA yields inferior results compared with patients who did not have hip OA [1]. Chronologic age in isolation is not an absolute contraindication to hip arthroscopy for patients in their 70s [73]. Subgroup analysis comparing operative versus nonoperative management for femoroacetabular impingement demonstrated a 32% reduction in the radiographic progression of osteoarthritis at long-term follow-up, though there were no significant differences in the risk of total hip arthroplasty [8]. There is some evidence that patients with femoroacetabular impingement syndrome who undergo hip arthroscopy may have a lower rate of progression of OA and conversion to total hip arthroplasty compared to similar patients initially treated nonoperatively [80]. At a mean follow-up of nearly 13 years, 7% of patients in the surgical group experienced progression to total hip arthroplasty, compared with 11% of the nonoperative control group [46]. At mean follow-up of 24.7 years, 14% of hips had symptomatic OA and 4% underwent total hip arthroplasty in patients with femoroacetabular impingement without surgical intervention [7].

Implant Selection: Hip resurfacing is an attractive option for young subjects under thirty years old [145].

Other Considerations: Absolute contraindications for total hip arthroplasty include active infection of the hip joint or any other region and any unstable medical illnesses that would significantly increase the risk of morbidity or mortality [69]. Asymptomatic bacteriuria has not been associated with postoperative surgical site infections and should not be considered a contraindication for total hip arthroplasty [69]. A documented patent ductus arteriosus or septal defect is an absolute contraindication for bilateral total hip procedures carried out under a single anesthetic [69]. Patients who had undergone total hip arthroplasty have impaired long-term self-reported physical quality of life and hip functionality but perform physically better than untreated patients with advanced hip osteoarthritis [26].

Complications

Hip Arthroscopy

Patients with hip osteoarthritis achieve inferior results after hip arthroscopy compared with patients who do not have osteoarthritis [1].

Total Hip Arthroplasty

Infection (PJI): Obesity increases the risk of infection after total hip arthroplasty due to mechanical wound problems associated with thick subcutaneous fat layers [157]. Obesity also prolongs drainage duration, which is associated with higher rates of periprosthetic infection [157]. Diabetes mellitus is an independent risk factor for infection after total joint arthroplasty [157]. Preoperative hemoglobin A1c levels greater than 7 are associated with an increased risk of periprosthetic infection after total joint arthroplasty [157].

Aseptic loosening: Some reports suggest that obesity may increase the chance of aseptic loosening after total hip arthroplasty [157].

Instability: Fixed spinal deformities secondary to scoliosis, previous spine fusion surgery, or ankylosing spondylitis may affect the functional positioning of the acetabular implant during total hip arthroplasty [157]. In patients with ankylosing spondylitis, the acetabular implant should be inserted in a more horizontal position with less anteversion to avoid anterior dislocation [157].

Thromboembolism: Patients having total hip replacement for acute fracture had higher rates of pulmonary embolism compared with osteoarthritis patients [162].

Wound complications: Rates of hematoma formation were higher in patients having total hip replacement for acute fracture compared with osteoarthritis patients, although these differences decreased over time [162].

Other Considerations: Patients who have undergone total hip arthroplasty have impaired long-term self-reported physical quality of life and hip functionality but still perform physically better than untreated patients with advanced hip osteoarthritis [26]. Younger patients with osteoarthritis are likely to return to high levels of activity after surgery, which may impact long-term wear-related implant survivorship [67]. Prolonged waiting time for total hip arthroplasty is a significant independent risk factor for reduced benefit after surgery [170]. In a 2018 study, 53% of patients with osteoarthritis had insomnia symptoms and 66% had obstructive sleep apnea [52]. In a 2014 Cochrane review, the effect of opioids in treating arthritis pain and improving function was minimal and did not outweigh the risk of adverse events or side effects [52]. Patients having total hip replacement for acute fracture had higher rates of mortality compared with osteoarthritis patients [162]. Rates of infection and dislocation were higher in patients having total hip replacement for acute fracture compared with osteoarthritis patients, although these differences decreased over time [162]. Having a femoral neck fracture versus osteoarthritis was associated with greater rates of medical complications, longer hospitalization, discharge to inpatient care facility, and unplanned readmission [162].

Hip Arthrodesis

Other Considerations: The survivorship of hip arthrodesis can be limited by symptomatic degenerative disease of the adjacent joints [19]. Rehabilitation after conversion of hip fusion to total hip arthroplasty is prolonged because of profound hip abductor weakness and associated limp [19].

Intra-articular Injections

Other Considerations: The most common adverse event for intra-articular injection of a cross-linked hyaluronic acid combined with triamcinolone hexacetonide was transient hip pain [32].

Disease Progression and Natural History

Other Considerations: For a patient who recently developed Tönnis 1 degenerative change, the probability of undergoing total hip arthroplasty in 10 years based on hip morphology was approximately one in three for dysplasia of the hip and one in five for both femoroacetabular impingement and normal morphology hips [70]. The approximate probability at 20 years for a patient who recently developed Tönnis 1 degenerative change to undergo total hip arthroplasty was two in three for dysplasia of the hip and one in two for both femoroacetabular impingement and normal morphology hips [70]. Kaplan-Meier survivorship estimated that 41% of patients with no contralateral hip symptoms develop symptoms at 10 years and 19% went on to total hip arthroplasty [70]. Complex traumatic hip dislocations were more likely to develop osteoarthritis (4/9, 44%) or osteonecrosis (3/9, 33%) [70]. Retention of any intra-articular fragments after traumatic hip dislocation was associated with development of posttraumatic osteoarthritis [70]. A DDH family history is a risk factor for the progression of hip osteoarthritis [83].

Recovery

Light activity (weeks): The provided evidence does not specify a typical week range for the return to desk work, driving, or light activities of daily living.

Full activity (months): The provided evidence does not specify a month range for the return to manual work, sport, or full range of motion and strength.

Complete recovery / outcome plateau (months): The provided evidence does not specify a month range for the stabilization of pain, strength, or final functional outcomes.

Rehabilitation protocol: A six-week physiotherapist-led exercise and education intervention resulted in sustained significant improvements in pain severity and interference in patients with hip or knee osteoarthritis awaiting arthroplasty [29]. Neuromuscular exercise effects were moderate in hip osteoarthritis [2].

Functional milestones: Intra-articular corticosteroid injections provide large, clinically meaningful short-term pain relief and functional improvement in hip osteoarthritis [15], although these benefits are not reliably sustained beyond three months [15]. Intra-articular steroid injection is an efficacious therapy for immediate and delayed pain reduction in hip osteoarthritis patients within 12 weeks [72]. Patients undergoing treatment for hip osteoarthritis with either platelet-rich plasma (PRP) or hyaluronic acid (HA) injections can expect to experience similarly beneficial short-term clinical outcomes [24]. The therapeutic effects of PRP and PRP+HA injections in hip osteoarthritis lasted longer (6 months) than HA injections [64], and the effects of PRP and PRP+HA injections on patients' performance, disability, and activities of daily living were superior to HA in the long run [64]. A single injection of amniotic suspension allograft provides relief of pain and improvement in patient-reported outcomes for up to one year in patients with moderate hip osteoarthritis [28], though the exact mechanism of action for amniotic suspension allograft in hip osteoarthritis remains unknown [28].

Other Considerations: Younger patients with osteoarthritis are likely to return to high levels of activity after surgery [67]; however, high levels of activity after surgery in younger patients may impact long-term wear-related implant survivorship [67]. Screening patients with hip osteoarthritis for depression early in the disease course may contribute to better patient-reported pain, health-related quality of life, and satisfaction after future total hip arthroplasty [44]. At 6-7 year follow-up, no deterioration in gait parameters was evident in non-operated individuals with hip osteoarthritis [187], and pain significantly improved in non-operated individuals with hip osteoarthritis at 6-7 year follow-up [187]. The only significant decline in functional status found in non-operated individuals with hip osteoarthritis at 6-7 year follow-up was in passive hip flexion and adduction range of motion [187]. At a mean follow-up of nearly 13 years, 7% of patients treated for symptomatic femoroacetabular impingement with hip arthroscopy experienced progression to total hip arthroplasty [46], while 11% of the nonoperative control group for femoroacetabular impingement experienced progression to total hip arthroplasty [46]. At mean follow-up of 24.7 years, 14% of hips in patients with femoroacetabular impingement without surgical intervention had symptomatic osteoarthritis [7], and 4% of hips in patients with femoroacetabular impingement without surgical intervention underwent total hip arthroplasty [7]. A developmental dysplasia of the hip family history is a risk factor for the progression of hip osteoarthritis [83]. Patients with long-segment lumbosacral fusion should be followed closely regarding hip osteoarthritis risk [42].

Key Evidence

• [L1] Patients with hip OA had inferior results compared with those who did not. [1] (10.1007/s11999-014-3943-9)
• [L2] While the effects were moderate in hip OA, they were only small in knee OA. [2] (10.3899/jrheum.130642)
• [L3] A clinical diagnosis of hip osteoarthritis was found in approximately 22% of young patients undergoing hip arthroscopy within 2 years. [3] (10.1186/s12891-019-2646-5)
• [L1] This study supports assertions that hip osteoarthritis is a prevalent condition whose treatment will continue to place important demands on health services, despite heterogeneity in study populations and diagnostic methods. [4] (10.1007/s11999-008-0625-5)
• [L2] Clinical disease severity varies widely at the time of total hip replacement for osteoarthritis, and in advanced hip OA clinical severity shows no correlation with radiographic severity. [5] (10.1186/1471-2474-10-19)
• [L1] However, it cannot be recommended as standard therapy in hip OA for wider populations, and therefore the indications remain a highly individualised matter. [6] (10.1007/s00402-007-0447-z)
• [L3] At mean follow-up of 24.7 years, 14% of hips had symptomatic OA and 4% underwent THA. [7] (10.1177/0363546520949179)
• [L4] Subgroup analysis comparing operative versus nonoperative management demonstrated a 32% reduction in the radiographic progression of osteoarthritis at long-term follow-up, though there were no significant differences in the risk of total hip arthroplasty. [8] (10.1177/23259671251326116)
• [L5] Future clinical trials investigating the natural history and treatment of femoroacetabular impingement will require multimodal staging systems for hip osteoarthritis because the optimal system will differ based on the size of the study population, the specific objective in question, and the time frame in which the investigator expects to see the specified end point. [9] (10.5435/00124635-201300001-00008)
• [L3] These characteristics may help to identify people with co-occurring LSS and knee or hip OA, which can be used to help guide clinical decision-making. [10] (10.1186/s12891-023-06356-3)
• [L4] Knee/hip pain within the last month was frequent among individuals aged 29–59 years, and multiple known osteoarthritis risk factors were associated with the presence of knee/hip pain. [11] (10.1186/s12891-018-2183-7)
• [L1] For clinical practice, no recommendation can be made regarding the use of hip injections for diagnosing hip OA. [12] (10.1016/j.arth.2013.12.008)
• [L2] Limited evidence on the use of PROs as an integrated part of clinical practice for patients with hip and knee osteoarthritis was found. [13] (10.1186/s12891-019-2620-2)
• [L4] Rapid destructive hip osteoarthritis represents an uncommon subset of arthrosis with rapid progression. [14] (10.1177/2325967120s00078)
• [L1] Intra-articular corticosteroid injections provides large, clinically meaningful short-term pain relief and functional improvement in hip OA, with benefits not reliably sustained beyond three months. [15] (10.1016/j.arth.2026.07.024)
• [L3] Patients who exhibited rapidly progressive osteoarthritis before undergoing total hip arthroplasty showed worse patient-reported outcomes compared with those who did not have rapid progression. [16] (10.1016/j.arth.2024.04.016)
• [L3] These findings question whether THA should be prioritized only for those patients who have severe hip OA symptoms, but require confirmation in a trial. [17] (10.1016/j.arth.2025.04.032)
• [L1] Patients undergoing treatment for hip OA with either PRP or HA injections can expect to experience similarly beneficial short-term clinical outcomes. [24] (10.1016/j.arthro.2021.11.005)
• [L4] The identification of clinical phenotypes and prognostic factors for outcomes in pain and disability will be a first step towards pre- and postoperative precision medicine for individuals with hip OA undergoing THA. [25] (10.1186/s12891-023-06326-9)
• [L3] Patients who had undergone total hip arthroplasty have impaired long-term self-reported physical quality of life and hip functionality but they still perform physically better than untreated patients with advanced hip osteoarthritis. [26] (10.1186/1471-2474-12-222)
• [L3] Early interventions to target muscle weakness and prevent the development of strength asymmetries that are characteristic of advanced hip OA appear warranted. [27] (10.1186/s12891-018-2230-4)
• [L4] This study demonstrates promising results for relief of pain and improvement in patient-reported outcomes with intra-articular ASA in patients with moderate osteoarthritis of the hip for up to one year, although the exact mechanism of action remains unknown. [28] (10.1016/j.arthro.2021.04.034)
• [L1] The intervention resulted in sustained significant improvements in pain severity and interference in patients with hip/knee osteoarthritis awaiting arthroplasty compared with a control group. [29] (10.1186/s12891-016-1088-6)
• [L4] No evidence exists on outcomes following non-operative management of FAI with concomitant Tönnis Grade 2 or more OA of the hip. [31] (10.1007/s00167-022-07274-y)
• [L3] The most common adverse event was transient hip pain. [32] (10.1016/j.jisako.2024.100363)
• [L1] There is evidence that multimorbid LSS with knee or hip OA occurs in people (0 to 54%), although results are based on studies with high risk of bias and surgical populations. [33] (10.1186/s12891-022-05104-3)
• [L1] [34] (10.1016/j.asmr.2021.07.029)
• [L2] [36] (10.1136/bjsports-2024-108222)
• [L1] [38] (10.1136/bjsports-2025-110144)
• [L3] The novel HiSS categorization supported the use of pelvic tilt to potentially improve the ability to discern HiSS types/pathologies in a subset of patients with hip osteoarthritis and spinal sagittal malalignment. [40] (10.5435/jaaos-d-18-00295)
• [L3] Particularly patients with long-segment lumbosacral fusion should be followed closely regarding hip osteoarthritis risk. [42] (10.1186/s13018-023-03932-0)
• [L3] Two-thirds of people with hip and/or knee osteoarthritis in Portugal have poor management of their pain levels. [43] (10.1186/s12891-022-06110-1)
• [L3] Screening patients with hip OA for depression early in the disease course may contribute to better patient-reported pain, HRQoL, and satisfaction after future THA. [44] (10.1097/corr.0000000000002681)
• [L3] At a mean follow-up of nearly 13 years, 7% of patients of the surgical group experienced progression to THA, compared with 11% of the nonoperative control group. [46] (10.1177/03635465231188114)
• [L4] The results demonstrate superior performance compared to other up-to-date methods, suggesting that the proposed method can serve as a supplementary tool to the KL grading scale for hip OA detection and severity assessment in clinical practice. [47] (10.1186/s12891-025-08911-6)
• [L3] Prior to total hip arthroplasty, individuals with hip osteoarthritis presented with an increased contralateral shift and forward displacement of the center of mass. [48] (10.1186/s13018-020-01663-0)
• [L3] [51] (10.1016/j.arthro.2013.07.149)
• [L4] The proposed AI model performed adequately in predicting hip OA progression and may be clinically applicable with additional datasets and validation. [53] (10.1186/s12891-024-08034-4)
• [L2] Cam morphology has been associated with the development of hip osteoarthritis, while the association between pincer morphology and hip osteoarthritis is much less clear. [54] (10.2519/jospt.2018.7816)
• [L2] Radiographic evidence of FAI is common in active patients with hip complaints. [60] (10.1007/s11999-010-1233-8)
• [L5] Intra-articular corticosteroid injections are safe and effective at reducing pain and improving function for up to three months in patients with symptomatic hip OA, with a low risk of adverse events. [61] (10.1177/23259671211066966)
• [L1] Although all 3 interventions were associated with improvement of pain and function in patients with hip OA, the therapeutic effects of PRP and PRP+HA injections lasted longer (6 months), and the effects of these two interventions on patients' performance, disability, and ADL were superior to HA in the long run. [64] (10.1186/s12891-022-05787-8)
• [L3] Insurance status, income, and gender were also associated with imaging and treatments performed in managing hip and knee osteoarthritis. [66] (10.1016/j.arth.2022.02.019)
• [L3] Younger patients with osteoarthritis are likely to return to high levels of activity after surgery, which may impact long-term wear-related implant survivorship. [67] (10.1007/s11999-014-3952-8)
• [L4] Consideration of sarcopenic obesity should be included in osteoarthritis patient assessments. [68] (10.1186/s12891-018-2175-7)
• [L1] IAST was proved to be an efficacious therapy in both immediate and delay pain reduction for hip OA patients within 12 weeks. [72] (10.1155/2020/6320154)
• [L3] Chronologic age in isolation is not an absolute contra-indication to hip arthroscopy. [73] (10.1007/s00167-019-05520-4)
• [L2] The findings suggest that spinal alignment and mobility should be considered when assessing risk and designing preventive intervention for radiographic progression of secondary hip OA. [77] (10.1016/j.joca.2017.12.005)
• [L1] There is some evidence that patients with FAIS who undergo hip arthroscopy may have a lower rate of progression of OA and conversion to THA compared to similar patients initially treated nonoperatively. [80] (10.1016/j.asmr.2025.101256)
• [L3] Based on our data, we recommend the Kellgren-Lawrence as the grading system for lower extremity osteoarthritis. [81] (10.1186/s13018-026-06695-6)
• [L3] A DDH family history is a risk factor for the progression of hip OA. [83] (10.1016/j.arth.2023.08.026)
• [L4] The study highlights the variability of acetabular anatomy in patients with primary OA, noting that acetabular offset can be accurately determined on conventional radiographs. [86] (10.1016/j.arth.2019.03.065)
• [L4] Distinct transcriptome profiles for early and late stage hip degeneration were identified along with key molecular contributors to the progression of hip OA. [87] (10.1016/j.arth.2022.03.013)
• [L4] [108] (10.1186/1471-2474-13-242)
• [L4] There was no main effect of radiographic disease severity on hip kinematic variability in the sagittal or frontal plane, and no significant differences in coordination of variability of segment couplings were observed. [116] (10.1002/jor.24609)
• [L3] Besides more commonly reported spatiotemporal parameters, only upper body motion provided nonredundant and sensitive parameters representing gait adaptations in individuals with hip OA. [117] (10.1186/s12891-021-04074-2)
• [L3] Reduced gait velocity, reduced sagittal plane joint excursion, and a reduced hip flexion moment in the late stance phase of gait were found to be evident already in hip osteoarthritis patients with mild to moderate symptoms, not eligible for total hip replacement. [123] (10.1186/1471-2474-13-258)
• [L3] Considering the LEFS' good psychometric qualities and ability to discriminate between pain and functioning, we recommend the LEFS as the outcome measure of choice to assess self-reported physical functioning in individuals with hip or knee osteoarthritis. [124] (10.1186/1471-2474-13-117)
• [L1] In adults with severe hip OA, THR reduced hip pain and improved self-reported hip function at 6 months compared with resistance training. [129] (10.2106/jbjs.25.00632)
• [L1] Evidence suggests that steroid injection is more effective than saline injection for the treatment of hip joint pain, and restoration of functional outcomes. [132] (10.1302/0301-620x.106b6.bjj-2023-1272.r1)
• [L5] The benefits of hip arthroscopy for patients with Tönnis grade 2 or greater hip osteoarthritis are ambiguous due to contradictory research and varying reliability of the Tönnis classification, necessitating shared decision-making between surgeon and patient. [136] (10.1016/j.arthro.2022.02.013)
• [L3] Subjects had 3.49 degrees less peak hip flexion and 8.82 degrees less extension angles. [139] (10.1002/jor.22772)
• [L4] Patients with hip osteoarthritis showed the poorest repeatability between gait recordings collected by different examiners, as compared to patients operated with a THA and healthy controls. [140] (10.1186/s12891-018-2145-0)
• [L1] CS injections are recommended as the most efficient agent in hip OA patients in the short term. [144] (10.1016/j.arthro.2019.09.043)
• [L3] The specific advantages of hip resurfacing make the procedure a very attractive option for young subjects. [145] (10.1007/s00264-012-1555-0)
• [L3] In patients with excessive hip adduction and pelvic tilt toward the swing limb during gait, gait modification may contribute to the reduction of hip joint loading. [147] (10.1186/s12891-019-3022-1)
• [L2] The reduced ability of flexion in the arthritic hip leads to posterior pelvic tilt in the relaxed-seated position, associated with compensatory increased lumbar flexion. [151] (10.1016/j.arth.2021.03.031)
• [L5] [158] (10.1016/j.arthro.2023.12.010)
• [L2] [159] (10.1177/23259671211050613)
• [L1] [170] (10.1097/01.blo.0000203477.19421.ed)
• [L3] Radiographic findings appeared to correspond with functional status in former ASF players with knee OA but not hip OA. [175] (10.1177/23259671261420422)
• [L4] The segmental electrical bioimpedance equipment can detect differences between limbs affected and unaffected by hip osteoarthritis. [177] (10.1186/s12891-023-06541-4)
• [L4] Nonoperative OA hip patients were generally unreceptive to using smart technologies, with the exception of smartphone applications. [181] (10.1016/j.arth.2022.02.026)
• [L4] [184] (10.5435/00124635-201300001-00003)
• [L2] At 6-7 year follow-up, no deterioration in gait parameters was evident in non-operated individuals, and the only significant decline in functional status was found in passive hip flexion and adduction ROM, while pain significantly improved. [187] (10.2519/jospt.2015.5441)
• [L4] Greater cross-sectional area of hip flexors might be associated with better quality of life. [188] (10.1186/s12891-020-03348-5)
• [L2] [194] (10.1136/bjsports-2024-109595)
• [L4] This pilot study suggests that radiological features, specifically joint space narrowing, might be of importance for the decision of viscosupplementation in patients with hip osteoarthritis, though further confirmation by larger scale trials is needed. [195] (10.1186/s12891-016-1359-2)
• [L1] Insufficient evidence exists to establish the effectiveness of physiotherapy exercise following primary hip replacement for osteoarthritis. [196] (10.1186/1471-2474-10-98)
• [L3] Spinal pathology was significantly associated with both the development and progression of hip osteoarthritis (HOA). [197] (10.1016/j.arth.2026.05.058)

See Also

• Total hip replacement
• Hip arthroscopy
• Femoroacetabular impingement
• Periacetabular osteotomy
• Avascular necrosis of the femoral head
• Hip resurfacing

References

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[17] Total Hip Arthroplasty versus Education and Exercise: A Secondary Analysis of Propensity Matched Data Comparing Outcomes Across Hip Osteoarthritis Symptom Severity. The Journal of Arthroplasty. 2025. DOI: 10.1016/j.arth.2025.04.032

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[25] Clinical phenotypes and prognostic factors in persons with hip osteoarthritis undergoing total hip arthroplasty: protocol for a longitudinal prospective cohort study (HIPPROCLIPS). BMC Musculoskeletal Disorders. 2023. DOI: 10.1186/s12891-023-06326-9

[26] Quality of life and functionality after total hip arthroplasty: a long-term follow-up study. BMC Musculoskeletal Disorders. 2011. DOI: 10.1186/1471-2474-12-222

[27] Individuals with mild-to-moderate hip osteoarthritis have lower limb muscle strength and volume deficits. BMC Musculoskeletal Disorders. 2018. DOI: 10.1186/s12891-018-2230-4

[28] A Single Injection of Amniotic Suspension Allograft Is Safe and Effective for Treatment of Mild to Moderate Hip Osteoarthritis: A Prospective Study. Arthroscopy. 2021. DOI: 10.1016/j.arthro.2021.04.034

[29] Significant improvements in pain after a six-week physiotherapist-led exercise and education intervention, in patients with osteoarthritis awaiting arthroplasty, in South Africa: a randomised controlled trial. BMC Musculoskeletal Disorders. 2016. DOI: 10.1186/s12891-016-1088-6

[31] No evidence exists on outcomes of non‐operative management in patients with femoroacetabular impingement and concomitant Tönnis Grade 2 or more hip osteoarthritis: a scoping review. Knee Surgery, Sports Traumatology, Arthroscopy. 2022. DOI: 10.1007/s00167-022-07274-y

[32] Intra-articular injection of a cross-linked hyaluronic acid combined with triamcinolone hexacetonide improves pain at six months in patients with mild to moderate hip osteoarthritis: A prospective observational study. Journal of ISAKOS. 2025. DOI: 10.1016/j.jisako.2024.100363

[33] Prevalence of multimorbid degenerative lumbar spinal stenosis with knee or hip osteoarthritis: a systematic review and meta-analysis. BMC Musculoskeletal Disorders. 2022. DOI: 10.1186/s12891-022-05104-3

[34] Abnormal Femoral Anteversion Is Associated With the Development of Hip Osteoarthritis: A Systematic Review and Meta‐Analysis. Arthroscopy, Sports Medicine, and Rehabilitation. 2021. DOI: 10.1016/j.asmr.2021.07.029

[36] Femoroacetabular impingement syndrome in middle-aged individuals is strongly associated with the development of hip osteoarthritis within 10-year follow-up: a prospective cohort study (CHECK). British Journal of Sports Medicine. 2024. DOI: 10.1136/bjsports-2024-108222

[38] Cam morphology and the risk of developing radiographic hip osteoarthritis within 8 years: an individual participant data meta-analysis of 23 886 hips from the world COACH consortium. British Journal of Sports Medicine. 2025. DOI: 10.1136/bjsports-2025-110144

[40] Radiographic Categorization of the Hip-spine Syndrome in the Setting of Hip Osteoarthritis and Sagittal Spinal Malalignment. Journal of the American Academy of Orthopaedic Surgeons. 2019. DOI: 10.5435/jaaos-d-18-00295

[42] Lumbosacral fusion increases the risk of hip osteoarthritis. Journal of Orthopaedic Surgery and Research. 2023. DOI: 10.1186/s13018-023-03932-0

[43] Prevalence of and factors associated with unmanageable pain levels in people with knee or hip osteoarthritis: a cross-sectional population-based study. BMC Musculoskeletal Disorders. 2023. DOI: 10.1186/s12891-022-06110-1

[44] What Factors Identified in Initial Osteoarthritis Management Are Associated With Poor Patient-reported Outcomes After THA? A Register-based Study. Clinical Orthopaedics & Related Research. 2023. DOI: 10.1097/corr.0000000000002681

[46] Progression of Osteoarthritis at Long-term Follow-up in Patients Treated for Symptomatic Femoroacetabular Impingement With Hip Arthroscopy Compared With Nonsurgically Treated Patients. The American Journal of Sports Medicine. 2023. DOI: 10.1177/03635465231188114

[47] An interpretable machine learning approach for predicting and grading hip osteoarthritis using gait analysis. BMC Musculoskeletal Disorders. 2025. DOI: 10.1186/s12891-025-08911-6

[48] Functional movement compensations persist in individuals with hip osteoarthritis performing the five times sit-to-stand test 1 year after total hip arthroplasty. Journal of Orthopaedic Surgery and Research. 2020. DOI: 10.1186/s13018-020-01663-0

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[53] Development and accuracy of an artificial intelligence model for predicting the progression of hip osteoarthritis using plain radiographs and clinical data: a retrospective study. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-08034-4

[54] The Prevalence of Cam and Pincer Morphology and Its Association With Development of Hip Osteoarthritis. Journal of Orthopaedic & Sports Physical Therapy. 2018. DOI: 10.2519/jospt.2018.7816

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[66] Racial and Ethnic Disparities in the Imaging Workup and Treatment of Knee and Hip Osteoarthritis. The Journal of Arthroplasty. 2022. DOI: 10.1016/j.arth.2022.02.019

[67] Are Younger Patients Undergoing THA Appropriately Characterized as Active?. Clinical Orthopaedics & Related Research. 2015. DOI: 10.1007/s11999-014-3952-8

[68] The impact of sarcopenic obesity on knee and hip osteoarthritis: a scoping review. BMC Musculoskeletal Disorders. 2018. DOI: 10.1186/s12891-018-2175-7

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[72] Intra‐Articular Steroid Injection for Patients with Hip Osteoarthritis: A Systematic Review and Meta‐Analysis. BioMed Research International. 2020. DOI: 10.1155/2020/6320154

[73] Patients aged in their 70s do not have a high risk of progressive osteoarthritis following arthroscopic femoroacetabular impingement correction and labral preservation surgery. Knee Surgery, Sports Traumatology, Arthroscopy. 2019. DOI: 10.1007/s00167-019-05520-4

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[80] Hip Arthroscopy for Femoroacetabular Impingement Syndrome Reduces the Risk for Developing Hip Osteoarthritis: A Systematic Review. Arthroscopy, Sports Medicine, and Rehabilitation. 2025. DOI: 10.1016/j.asmr.2025.101256

[81] Reliability of radiographic knee and hip osteoarthritis classification between radiologists and orthopaedic surgeons. Journal of Orthopaedic Surgery and Research. 2026. DOI: 10.1186/s13018-026-06695-6

[83] Family History of Developmental Dysplasia of the Hip is a Risk Factor for the Progression of Hip Osteoarthritis. The Journal of Arthroplasty. 2024. DOI: 10.1016/j.arth.2023.08.026

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[117] Independent and sensitive gait parameters for objective evaluation in knee and hip osteoarthritis using wearable sensors. BMC Musculoskeletal Disorders. 2021. DOI: 10.1186/s12891-021-04074-2

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[124] The Dutch Lower Extremity Functional Scale was highly reliable, valid and responsive in individuals with hip/knee osteoarthritis: a validation study. BMC Musculoskeletal Disorders. 2012. DOI: 10.1186/1471-2474-13-117

[129] In Adults with Severe Hip Osteoarthritis, Total Hip Replacement Reduced Hip Pain and Improved Self-Reported Hip Function at 6 Months Compared with Resistance Training. Journal of Bone and Joint Surgery. 2025. DOI: 10.2106/jbjs.25.00632

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[140] Different reliability of instrumented gait analysis between patients with unilateral hip osteoarthritis, unilateral hip prosthesis and healthy controls. BMC Musculoskeletal Disorders. 2018. DOI: 10.1186/s12891-018-2145-0

[144] Different Intra‐articular Injections as Therapy for Hip Osteoarthritis: A Systematic Review and Network Meta‐analysis. Arthroscopy. 2020. DOI: 10.1016/j.arthro.2019.09.043

[145] Hip resurfacing in patients under thirty years old: an attractive option for young and active patients. International Orthopaedics. 2012. DOI: 10.1007/s00264-012-1555-0

[147] Gait kinematics of the hip, pelvis, and trunk associated with external hip adduction moment in patients with secondary hip osteoarthritis: toward determination of the key point in gait modification. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-019-3022-1

[151] Differences in Spinopelvic Characteristics Between Hip Osteoarthritis Patients and Controls. The Journal of Arthroplasty. 2021. DOI: 10.1016/j.arth.2021.03.031

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[158] Clinical Equipoise in the Management of Patients With Femoroacetabular Impingement Syndrome and Concomitant Tönnis Grade 2 Hip Osteoarthritis or Greater: An International Expert‐Panel Delphi Study. Arthroscopy. 2023. DOI: 10.1016/j.arthro.2023.12.010

[159] Automated Risk Stratification of Hip Osteoarthritis Development in Patients With Femoroacetabular Impingement Using an Unsupervised Clustering Algorithm: A Study From the Rochester Epidemiology Project. Orthopaedic Journal of Sports Medicine. 2021. DOI: 10.1177/23259671211050613

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[175] Factors Associated With Functional Outcomes in Former Professional American-Style Football Players With Symptomatic Knee and Hip Osteoarthritis. Orthopaedic Journal of Sports Medicine. 2026. DOI: 10.1177/23259671261420422

[177] Segmental bioelectrical impedance analysis can detect differences between the affected and non-affected limbs in individuals with hip osteoarthritis. BMC Musculoskeletal Disorders. 2023. DOI: 10.1186/s12891-023-06541-4

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[181] Patient Perceptions of Wearable and Smartphone Technologies for Remote Outcome Monitoring in Patients Who Have Hip Osteoarthritis or Arthroplasties. The Journal of Arthroplasty. 2022. DOI: 10.1016/j.arth.2022.02.026

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[187] Gait Characteristics, Symptoms, and Function in Persons With Hip Osteoarthritis: A Longitudinal Study With 6 to 7 Years of Follow-up. Journal of Orthopaedic & Sports Physical Therapy. 2015. DOI: 10.2519/jospt.2015.5441

[188] Association between hip muscle cross-sectional area and hip pain and function in individuals with mild-to-moderate hip osteoarthritis: a cross-sectional study. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-03348-5

[194] Severe pincer morphology is associated with incident hip osteoarthritis: prospective individual participant data from 18 935 hips from the World COACH consortium. British Journal of Sports Medicine. 2025. DOI: 10.1136/bjsports-2024-109595

[195] Predictors of response to viscosupplementation in patients with hip osteoarthritis: results of a prospective, observational, multicentre, open-label, pilot study. BMC Musculoskeletal Disorders. 2017. DOI: 10.1186/s12891-016-1359-2

[196] Effectiveness of physiotherapy exercise following hip arthroplasty for osteoarthritis: a systematic review of clinical trials. BMC Musculoskeletal Disorders. 2009. DOI: 10.1186/1471-2474-10-98

[197] Differential Effects of Degenerative Spine Disease and Spinal Fusion on the Risk and Progression of Hip Osteoarthritis: A Nationwide Time-Varying Cohort Study. The Journal of Arthroplasty. 2026. DOI: 10.1016/j.arth.2026.05.058