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Distal femur fracture

70 citationsUpdated Sep 2026
Illustration: knee

For patients: a plain-language version of this topic is available. See the patient guide.

Overview

Distal femoral fractures present significant management challenges due to variable bone quality and complex fracture patterns [4]. Surgical treatment is indicated to stabilize these injuries, as non-surgical management is a rare option [9]. Internal fixation is recommended for most displaced distal femoral fractures in adults to achieve anatomic reduction and stable fixation, facilitating early mobilization [4]. While modern solutions display a concerning complication rate from nonunion and malunion [1], specific techniques offer favorable outcomes. Treatment using a locking plate showed favorable results in osteoporotic distal femoral fractures [6], and distal femoral nailing serves as a reliable alternative with a low complication rate [8]. Minimally-invasive internal fixation of distal extra-articular fractures with a locking plate combines the principles of internal fixation in a closed fracture site with assembly stability [11].

In geriatric populations, operative stabilization carries substantial risk. Nearly 1 in 5 patients older than 70 years developed a nonunion after ORIF of an intraarticular distal femur fracture [3]. A study confirmed a high rate of one-year mortality (25%) and postoperative medical complications in geriatric patients with distal femur fractures [10]. In elderly patients, double plate fixation is a useful method offering adequate exposure, easy manipulation, anatomical reduction, and stable fixation [39]. Common indications for dual-implant fixation include nonunion treatment and comminuted fractures with bone loss [52]. Operative stabilization can be successfully and equally well achieved using either a monoaxial or a polyaxial locking plate [58].

The current literature evaluating surgically treated distal femur fractures lacks a consistent definition of radiographic fracture union, and the appropriate time point to make this judgement remains unclear [2]. Long-term results of indirect reduction techniques of distal femoral fractures treated with the condylar plate were good to excellent in 82% of cases [20]. Minimally invasive implants for the treatment of distal femoral fractures did not differ significantly for epidemiology, fracture type, conversion procedures, infection rate, malalignments, and subjective and objective findings at the 1-year followup [33]. Retrograde intramedullary nailing appears to be an appropriate treatment for complete articular distal femur fractures with a potentially decreased rate of nonunion [35].

Anatomy & Pathophysiology

Bony Anatomy

The distal femur exhibits distinct morphological asymmetries between the medial and lateral condyles. The medial femoral condyle is larger, projects farther posteriorly and distally, and possesses a large, convex articular surface [69, 83]. In contrast, the lateral femoral condyle projects farther anteriorly and is wider in the medial-lateral direction [69]. The lateral condyle also has a convex articular surface with a broader mean anterior-posterior dimension than the medial condyle, a feature that allows internal rotation of the distal femur with knee extension [83]. The lateral trochlear facet resists lateral subluxation of the patella [83].

Key osseous landmarks include the medial epicondyle, which is the most anterior and distal prominence of the distal femur [69]. Proximal and posterior to the medial epicondyle lies the adductor tubercle, a prominence on the medial condyle that serves as the insertion site for the adductor magnus muscle [69, 83]. Slightly distal and posterior to the adductor tubercle is the gastrocnemius tubercle [69]. Anteriorly, the trochlear groove separates the femoral condyles and constitutes the patellofemoral articulation [69]. The sulcus terminalis is a small ridge on the lateral femoral condyle just distal to the intercondylar notch that separates the patellofemoral and tibiofemoral articular surfaces [69]. This transverse ridge extends from the oblique facets of the femoral trochlea and is deeper on the lateral condyle than on the medial condyle [83]. The intercondylar notch, which is of variable width, serves as the attachment site for the cruciate ligaments [69].

Ligaments

The anterior cruciate ligament (ACL) is an intra-articular ligament that is technically extrasynovial, as it is surrounded by synovium [81]. It travels from the medial border of the lateral femoral condyle to its insertion site anterolateral to the medial tibial spine [40]. The ACL prevents anterior translation and rotation of the tibia on the femur [40]. Its femoral attachment is a semicircular area, 20 mm long and 10 mm wide, located on the posteromedial aspect of the lateral femoral condyle, posterior to the lateral intercondylar ridge [69, 81]. The tibial attachment is a broad, irregular, oval-shaped area, 30 mm long and 10 mm wide, situated slightly medial and anterior to the midline between the medial and lateral tibial spinous processes [69]. The tibial insertion is 120% larger than the femoral insertion [81].

The ACL has a variable length of 22 to 41 mm and a width of 7 to 12 mm, consistently narrowest in the midsubstance [81]. The mean length is 33 mm and the mean midsubstance width is 11 mm [69]. The ligament is composed of 90% type I collagen and 10% type III collagen [69]. The ACL attachment is usually oval in shape, with the anteromedial (AM) bundle arising from the superior and anterior aspects and the posterolateral (PL) bundle arising from the posterior and inferior aspects [81]. These bundles are often separated by the lateral bifurcate ridge, which runs from anterior to posterior on the femur [81]. On a clock-face description based on the posterior outlet of the femoral intercondylar notch, the bulk of the AM bundle is attached between 9.30 and 11.30 o'clock, and the PL bundle between 8.30 and 10 o'clock [81]. The distance on the femur between the centers of the AM and PL bundles varies from 8 to 10 mm depending on the size of the knee [81].

The posterior cruciate ligament (PCL) runs from the lateral aspect of the medial femoral condyle to the posterior aspect of the tibia, just below the joint line [40]. It prevents posterior subluxation of the tibia on the femur [40]. The PCL has a mean length of 38 mm and a mean width of 13 mm [83]. Its femoral attachment is broad and crescent-shaped on the anterolateral medial femoral condyle, with a mean length of 30 mm and mean width of 5 mm [83]. The tibial insertion onto the posterior central sulcus is 10 to 15 mm distal to the joint line of the knee [83]. The PCL inserts on the anteromedial wall of the intercondylar notch, while the ACL inserts on the posterolateral wall [83]. The PCL consists of two bundles: the anterolateral bundle is stronger and stiffer than the posteromedial bundle, is tight in knee flexion, and the posteromedial bundle is tight in knee extension [83].

The medial collateral ligament (MCL) has superficial and deep portions which stabilize the knee to valgus stresses [40]. It originates on the femoral sulcus approximately 3.2 cm proximal and 4.8 cm posterior to the articular surface of the femur at the knee [83]. The lateral collateral ligament (LCL) runs from the lateral femoral condyle to the head of the fibula and is the main stabilizer against varus stress [40]. The popliteofibular ligament is present in 90% of knees and runs from the tendon of the popliteus muscle to the styloid on the posterior fibular head [40].

Biomechanically, the ACL is typically subjected to peak loads of 170 N during walking and up to 500 N with running [84]. The ultimate strength of the ACL in young patients is about 1750 N [84]. The ACL fails by serial tearing at 10% to 15% elongation [84]. Sectioning the PCL increases contact pressures in the medial compartment and the patellofemoral joint [84].

Menisci

The menisci are C-shaped, crescent-shaped fibrocartilaginous disks with a triangular cross section situated between the femoral condyles and tibial plateau [40, 79, 83]. They provide shock absorption, allow for increased congruency between joint surfaces, enhance joint stability, and aid in the distribution of synovial fluid [40]. The menisci provide a concave surface with which the convex femoral condyles can articulate [40]. They consist of type I collagen fibers arranged obliquely, radially, and vertically [83].

The medial meniscus has a semicircular shape which covers approximately 50% to 60% of the medial tibial plateau in adulthood [79]. It is firmly attached to the joint capsule along its entire peripheral edge and to the deep medial collateral ligament, limiting its mobility [40, 79]. The posterior horn of the medial meniscus averages 11 mm in the anterior-posterior dimension, whereas the anterior horn is narrower [79]. The anterior horn attaches to the tibia anterior to the ACL near the intercondylar fossa [79]. The posterior root attachment lies in the posterior intercondylar fossa between the lateral meniscus and PCL [79]. The menisco-tibial (coronary) ligament stabilizes the medial meniscus through its attachment from the inferior aspect of the posterior horn to the tibia [79]. Due to its firm attachment, the medial meniscus has less mobility than the lateral meniscus and is more susceptible to tearing when trapped between the femoral condyle and tibial plateau [40].

The lateral meniscus has a more circular C-shape with symmetric sizes of the anterior and posterior horns [79]. It is larger than the medial meniscus and covers a larger proportion of the tibial plateau [40, 83]. The lateral meniscus carries a greater share of the lateral compartment pressure than the medial meniscus carries for the medial compartment [40]. Its anterior root attaches anterior to the intercondylar eminence and just lateral to the ACL insertion site on the tibia [79, 83]. The posterior root attaches posterior to the lateral tibial spine just anterior to the medial meniscus posterior root [79]. The lateral meniscus is attached to the anterior and posterior capsule, but there is a region posterolaterally where it is not firmly attached, allowing for greater meniscal mobility [40, 79]. The popliteomeniscal fascicles extend from the lateral meniscus to the posterior capsule to create the popliteal hiatus [79].

The transverse, or intermeniscal, ligament connects the anterior horns of the medial and lateral menisci [79]. The meniscofemoral ligaments are variably present structures which connect the posterior horn of the lateral meniscus to the medial femoral condyle [79]. They originate from the posterior horn of the lateral meniscus and insert into the substance of the PCL and the medial femoral condyle [79, 83]. The ligament of Humphrey crosses anterior to the PCL and the ligament of Wrisberg crosses posteriorly [79]. A single meniscofemoral ligament is present in 93% of the population and both ligaments are present in 70% [83].

Vascular supply to the menisci is derived from the geniculate arteries, which penetrate into 20% to 30% of the peripheral medial meniscus and 10% to 25% of the peripheral lateral meniscus [83]. The menisci have three zones based on vasculature and extracellular matrix composition: white-white (ww), red-white (rw), and red-red (rr) [79]. The inner one-third is avascular and called the white-white zone [79]. The middle zone is called the red-white zone because it has limited vasculature [79]. The back one-third is called the red-red zone because it is the most vascularized tissue region with access to blood supply through vessels arising from the geniculate arteries [79]. Mean lateral meniscus excursion is 11.2 mm versus a mean medial meniscus excursion of 5.1 mm occurring from knee extension to flexion [79].

Vascular and Nerve Anatomy

The blood supply to the knee is formed from an anastomosis around the knee derived from the descending geniculate artery, medial and lateral superior geniculate arteries, medial and lateral inferior geniculate arteries, middle geniculate artery, and anterior tibial recurrent arteries [69]. The middle geniculate artery is the primary blood supply to both the ACL and the PCL [69, 83]. The inferior geniculate arteries pass deep to their respective collateral ligaments [69]. The blood supply of the patella is derived from the geniculate artery complex with some contribution from the anterior tibial recurrent artery and primarily exists in the middle to inferior portions of the patella [69]. The popliteal artery is near the PCL and the distance increases with knee flexion [83].

The knee is innervated by branches of the femoral nerve (L2, L3, L4), obturator nerve (L2, L3, L4), and sciatic nerve (L4, L5, S1, S2) [69]. The largest nerve providing innervation of the intra-articular knee is the posterior articular branch of the tibial nerve [69]. This branch supplies the infrapatellar fat pad, the synovial covering over the cruciate ligaments, and the periphery of the meniscus [69]. It also provides innervation to both the ACL and the PCL [83]. Nerves to the cruciate ligaments contain vasomotor and pain fibers as well as mechanoreceptors that may be involved in proprioception [69]. The infrapatellar branch of the saphenous nerve arises proximal to the knee joint medially and crosses distal to the patella to innervate the skin over the region of the anterior knee and proximal tibia [69].

Soft Tissue Stabilizers and Kinematics

The joint capsule and the collateral ligaments are the principal extraarticular static stabilizing structures [72]. The capsule is a sleeve of fibrous tissue extending from the patella and patellar tendon anteriorly to the medial, lateral, and posterior expanses of the joint [72]. The medial capsule is more distinct and well defined than its lateral counterpart [72]. The menisci are attached firmly at the periphery to the capsule, especially so medially and less so laterally [72]. Laterally, the passage of the popliteal tendon through the popliteal hiatus to its origin on the femoral condyle produces a less secure meniscal attachment than is present medially [72].

The capsular structures, along with the medial and lateral extensor expansions of the quadriceps musculature, are the principal stabilizing structures anterior to the transverse axis of the joint [72]. The anteromedial and anterolateral portions of the capsule are relatively thin structures but are reinforced by the medial and lateral patellar retinacular expansions [72]. These portions are significant in protecting the anteromedial and anterolateral aspects of the knee against subluxation and rotational excesses [72]. Posterior to the transverse axis, the capsule is reinforced by the collateral ligaments and the medial and lateral hamstring muscles, as well as by the popliteus muscle and the iliotibial band [72].

Warren and Marshall divided the knee into three layers: Layer I includes the deep fascia or crural fascia; layer II is composed of the superficial MCL, various structures anterior to this ligament, and the ligaments of the posteromedial corner; and layer III is made up of the capsule of the knee joint and the deep MCL [72]. The posteromedial corner of the knee has five major components: the posterior oblique ligament (POL), the semimembranosus tendon and its expansions, the oblique popliteal ligament (OPL), the posteromedial joint capsule, and the posterior horn of the medial meniscus [78].

The POL is a thickening of the medial capsular ligament attached proximally to the adductor tubercle of the femur and distally to the tibia and posterior aspect of the capsule [78]. The distal attachment of the POL is composed of three arms: the prominent tibial arm, the superior capsular arm, and the poorly defined inferior distal arm [78]. The central portion of the POL is the thickest and probably the most important arm, originating in the region of the adductor tubercle and coursing posteriorly and obliquely to insert at the posteromedial corner of the tibia near the insertion of the direct head of the semimembranosus tendon [78]. The superior arm of the POL passes posteriorly, blending with the posterior capsule and the OPL as it separates from the semimembranosus tendon [78]. The inferior and distal groups of fibers of the POL pass superficially over the insertion of the semimembranosus tendon, attach to the tibia and fascia inferiorly, and probably have little functional importance [78].

The semimembranosus tendon has five expansions: the direct arm, the anterior or deep arm, the arm to the POL or capsular arm, the arm to the OPL, and the expansion to the popliteus aponeurosis or the inferior arm [78]. The OPL is a broad fascial band originating from the capsular arm of the POL and the lateral expansion of the semimembranosus to cross the posterior aspect of the knee [78]. The OPL passes laterally and proximally toward the lateral femoral condyle and attaches to the meniscofemoral portion [78].

Classification

AO/OTA: The AO/OTA classification system defines fracture patterns in distal femur fractures, with Type C injuries representing intraarticular fractures [22]. Type C distal femur fractures present with four main fracture patterns, most of which contain a central sagittal intercondylar split with a high proportion of medial or lateral coronal fracture lines [23]. In a cohort of 18 closed, non-pathological intraarticular distal femur fractures treated with retrograde intramedullary nailing and compression bolts, the distribution was eight Type C1, seven Type C2, and three Type C3 [22]. In a series of 15 high-energy open supracondylar femur fractures with bone loss, all fractures had intraarticular involvement and were classified as seven Type C2 and eight Type C3 injuries [122]. Epidemiologically, AO/OTA type A fractures mainly involve elderly, relatively dependent female subjects [14].

Letenneur: Treatment of coronal plane distal femur fractures (Busch-Hoffa fractures) should be approached using a modified Letenneur classification to guide treatment, approach, and fixation [116].

NUSS: The Non-Union Scoring System (NUSS) is an appropriate scoring system to classify and stratify non-unions and to enable the surgeon to choose the correct treatment [114].

Other Considerations: In a population-based study of 302 distal femur fractures, the overall incidence was 8.7/100,000/year, with a rapid increase in incidence observed after the age of 60 years in both genders [7]. This study also noted a considerable female predominance in distal femur fractures after the age of 60 years [7]. The current literature evaluating surgically treated distal femur fractures lacks a consistent definition of radiographic fracture union, and the appropriate time point to make this judgement is unclear [2]. Inter-observer agreement for defining union on radiographs in the femoral group was 68% [54]. In the femoral group, the ability to correctly chronologically rank radiographs was 62% [54]. Mean callus formation was 17 mm in the united group and 2.3 mm in the un-united group [54]. A simple classification system connecting fracture patterns to treatment algorithms can assist surgeons in obtaining optimal clinical results for periprosthetic fractures of the knee [99].

Clinical Presentation

Distal femur fractures occur at an overall incidence of 8.7/100,000/year [7]. The mean age at fracture is 62.2 years [7], with a gender distribution of 33.4% males and 66.6% females [7]. Specifically, the mean age at fracture is 44.0 years for males and 71.6 years for females [7]. After the age of 60 years, incidence increases rapidly in both genders, with a considerable female predominance observed in this demographic [7]. Low-energy injuries constitute the primary trauma mechanism in population-based studies [7].

Fracture Patterns and Classification

AO/OTA type A distal femur fractures mainly involve elderly, relatively dependent female subjects [14]. C-type distal femur fractures present with four main fracture patterns [23]. Most C-type patterns contain a central sagittal intercondylar split [23], and a high proportion contain medial or lateral coronal fracture lines [23].

Complications and Prognosis

Geriatric patients with distal femur fractures face a high rate of one-year mortality, reported at 25% [10], and experience a high rate of postoperative medical complications [10]. Distal femoral periprosthetic fractures are associated with high morbidity and mortality [17]. Bilateral closed femoral shaft fractures carry an increased risk of complications [19]. Distinct zones of compromised blood supply exist in the middle and lower segments of the femur, which may predispose these areas to an increased risk of non-union [24].

Investigations

Plain radiography: Plain radiographs serve as the appropriate initial imaging studies for most knee conditions, allowing assessment of traumatic injury, arthritis, patellofemoral alignment, osteochondral injury, bone neoplasm, and surgical implants [87]. Non–weight–bearing radiographs may identify acute distal femur fracture without the risk of fracture displacement [87]. For articular cartilage evaluation, weight-bearing AP (extension) views assess cartilage loss from the distal femur and tibial plateau, while weight-bearing PA (Rosenberg; flexion) views assess cartilage loss from the posterior femur and tibial plateau [87]. Weight-bearing AP and lateral views and an axial view of the patellofemoral joint should be reviewed for articular cartilage evaluation [91]. Radiographs can underestimate isolated chondral lesions but may demonstrate joint space narrowing, osteophytes, sclerosis, and cysts [91]. The ability to detect subtle narrowing or an isolated chondral defect on the flexion surface may be improved with a semiflexed PA view [91].

CT: Computed tomography provides enhanced bone detail through three-dimensional study performed with ionizing radiation [87]. CT imaging in the axial, sagittal, and coronal planes may help visualize fracture lines and displacement [87]. Three-dimensional CT reconstructions may help with preoperative planning for complex intra-articular fractures [87].

MRI: MRI may identify the degree of articular cartilage injury, including chondrosis and full-thickness cartilage loss [87]. MRI may identify the presence of associated bone marrow edema and the location of articular cartilage injury [87]. MRI can be used to evaluate articular cartilage morphology [91]. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) at 26 weeks follow-up predicts non-union consolidation with a sensitivity of 75% and specificity of 87% [186].

Other Considerations: Surveillance radiographs in the first 12 weeks after tibial and femoral intramedullary fixation do not result in changes in management [32]. The ability of observers to correctly chronologically rank radiographs in the femoral group was 62% [54]. C-type distal femur fractures can present with four main fracture patterns, most containing a central sagittal intercondylar split with a high proportion of medial or lateral coronal fracture lines [23]. Distal femur intra-articular coronal plane fractures can yield large anterior and posterior condylar fracture fragments of either the medial condyle, lateral condyle, or both condyles [180].

Treatment

Non-Operative

The provided evidence base does not detail specific conservative management protocols such as weight loss, physical therapy regimens, or pharmacological interventions for distal femur fractures.

Operative

Indications: Management of distal femur fractures remains challenging due to bone quality and fracture patterns [4]. Clinical and radiographic assessment of both soft-tissue and osseous injury to the distal femur helps define surgical treatment options [42]. Substantial improvements in implant design and understanding the determinants of achieving a good clinical outcome have been achieved in the management of these injuries [42]. An understanding of expected outcomes and potential postoperative complications related to the surgical management of these injuries is important for optimal results [42].

Surgical Approach / Technique: Surgical management requires a clear understanding of the unique anatomy of the distal femur as well as a comprehensive knowledge of the implant and how it can be used in a biologic-preserving manner to achieve an anatomic reduction and enable fracture healing [42]. A medial approach is a reasonable and safe treatment option for femoral fractures associated with vascular injury [60]. In a distal femur fracture with a simple fracture pattern, using positional screws to sustain the reduced interfragmentary gap may achieve a more rapid union by reducing fracture gap [30].

Implant Selection: Retrograde intramedullary nailing is a reliable alternative in distal femoral fracture treatment with a low complication rate [8]. Intramedullary nailing may be a superior treatment compared with anatomical locking plates for fractures of the distal femur [55]. While prospective data is required, retrograde intramedullary nailing does appear to be an appropriate treatment for complete articular distal femur fractures with a potentially decreased rate of nonunion [35]. Plating has a definite place in the management of those fractures of the shaft of the femur that are unsuitable for medullary nailing [16]. Intraoperative stabilization of distal femur fractures can be successfully and equally well achieved using either a monoaxial or a polyaxial locking plate [58]. In a multicenter randomized trial of adult patients with an AO/OTA type 33A or 33C distal femoral fracture, similar clinical and radiographic healing outcomes were observed in the far cortical locking and standard fixation groups [57]. Double plate fixation for comminuted fractures of the distal femur can improve knee mobility at 6 months postoperatively, reduce overall postoperative complications, and decrease the incidence of malunion healing [37]. The Ilizarov fixator was an effective treatment modality of open comminuted distal femur fractures with high union rate, adequate alignment and satisfactory functional outcomes [106].

Periprosthetic Fractures: Open reduction internal fixation and distal femoral replacement for the treatment of periprosthetic distal femur fractures have similar surgical complication and reoperation profiles [34]. The authors advocate a minimum of 10 cortices of fixation above and below the fracture and recommend bone grafting if the soft tissue envelope is violated for periprosthetic femoral fractures around well-fixed total hip and knee implants [125].

Geriatric and Special Populations: Nearly 1 in 5 patients older than 70 years developed a nonunion after open reduction internal fixation of an intraarticular distal femur fracture [3]. The use of the LISS in combination with autogenous bone grafting adequately addresses nonunion fixation of the distal femur in elderly patients, achieving bone healing and preservation of knee function even in severe osteoporosis with substantial bone defects [119].

Revision: The failure rate of treatment of nonunions of the distal femur with internal fixation and autologous bone grafting remains high at 20% to 30% [47]. Complete clinical and radiological union was achieved in all cases in a mean duration of 5.2 months when using augmentation plating in management of failed femoral nailing [25]. All fractures progressed to clinical and radiological union at final follow-up when treated with the Polyax Locked Plating System for fixation of distal femoral non-implant related and periprosthetic fractures [29]. A surgical algorithm for the management of recalcitrant distal femur nonunions takes into account four important factors necessary to achieve a successful outcome: adequacy of distal femoral bone stock, extent of the medial void, alignment of the fracture, and stability of the fixation [43]. Treating neglected femoral diaphyseal fractures with a two-stage surgery is a satisfactory therapy showing reliable bony union [49]. The results demonstrated satisfactory healing for the treatment of diaphyseal nonunions of the femur and tibia using an expandable nailing system [111]. The article reviews various techniques proposed for managing aseptic diaphyseal long bone non-unions that do not require removal of the existing nail, noting that while some methods like augmentation plating show high success rates, evidence for others such as ultrasound and electrostimulation remains inconclusive or weak [107]. In case of non-union, its treatment should consider preservation of the blood supply at the fracture site [130].

Other Considerations: Clinicians should take into account risk factors when managing patients with long bone fractures, particularly the femur and tibia in order to minimise the risk of non-union [5]. Delayed unions and non-unions of fractures continue to be of great interest and are associated with significant patient morbidity [38]. Despite modern treatment, the patient-reported outcomes of lower limb long bone shaft fractures do not return to normal at one year [15].

Complications

Nonunion and Malunion: The risk of nonunion is elevated in specific patient populations and fracture patterns. Nearly 1 in 5 patients older than 70 years developed a nonunion after open reduction and internal fixation of an intraarticular distal femur fracture [3]. In a series of 55 patients with periprosthetic distal femur fractures treated with precontoured lateral locking plates, 18% developed nonunion [18]. For comminuted fractures of the distal femur, double plate fixation can decrease the incidence of malunion healing [37].

Infection and Perioperative Complications: Periprosthetic distal femur fractures treated with precontoured lateral locking plates carry an overall complication rate of 24% [18]. Double plate fixation for comminuted fractures of the distal femur can reduce overall postoperative complications [37]. Bilateral closed femoral shaft fractures should be treated with caution due to the increased risk of complications [19].

Geriatric and Systemic Outcomes: Geriatric patients with distal femur fractures have a high rate of one-year mortality (25%) and postoperative medical complications [10]. Osteoporosis influences the late period of fracture healing in femoral shaft fractures treated with intramedullary nailing [63].

Functional and Quality of Life: While the acute fracture and complications may have resolved clinically, the detrimental effect on a patient's quality of life persists up to 12 months after the injury [28].

Recovery

Complications and Nonunion: Delayed unions and non-unions of fractures are associated with significant patient morbidity [38].

Healing and Union Assessment: Complete clinical and radiological union was achieved in all cases of failed femoral nailing treated with augmentation plating in a mean duration of 5.2 months [25]. All fractures progressed to clinical and radiological union at final follow-up when treated with the Polyax Locked Plating System for distal femoral non-implant related and periprosthetic fractures [29]. Radiographic evidence of fracture union was observed at an average of 4.75±1.75 months (range 3 to 8 months) following autologous concentrated bone-marrow grafting for femoral shaft non-unions after locked intramedullary nailing [67].

Functional Outcomes and Quality of Life: The ROM of hip and knee returns to normal over time, regardless of the nailing method used [27]. Closed fracture and regular follow up were determining factors for better functional outcomes in distal femur fractures treated by open reduction and internal fixation using a distal femur locking plate [48]. PROMs provide insight into the natural history of the patient experience after tibial fracture but have limited utility as a measure of structural bone healing [56].

Treatment Efficacy and Outcomes: Distal femur fractures treated with retrograde intramedullary nails or lateral locked plates showed no notable differences in revision surgery rates, radiographic healing, or qualitative clinical outcomes [13].

Key Evidence

  • [L5] Despite rapid adoption, modern solutions for distal femur fractures display a concerning complication rate, specifically from nonunion and malunion. [1] (10.5435/jaaos-d-17-00706)
  • [L4] The current literature evaluating surgically treated distal femur fractures lacks consistent definition of radiographic fracture union, and the appropriate time point to make this judgement is unclear. [2] (10.2106/jbjs.rvw.23.00223)
  • [L3] Nearly 1 in 5 patients older than 70 years developed a nonunion after ORIF of an intraarticular distal femur fracture. [3] (10.1016/j.arth.2016.06.006)
  • [L1] Clinicians should take in to account these findings when managing patients with long bone fractures, particularly the femur and tibia in order to minimise the risk of non-union. [5] (10.1016/s0020-1383(15)30049-8)
  • [L4] Treatment using a locking plate showed favorable outcomes in osteoporotic distal femoral fractures. [6] (10.1016/j.otsr.2017.08.008)
  • [L3] [7] (10.1007/s00264-017-3665-1)
  • [L4] Our results suggest that the DFN is a reliable alternative in distal femoral fracture treatment with a low complication rate. [8] (10.1016/s0020-1383(03)00191-8)
  • [L4] Surgical treatment is indicated to stabilize distal femur fractures as non-surgical treatment is a rare option. [9] (10.1016/j.otsr.2012.10.014)
  • [L3] The study confirms a high rate of one-year mortality (25%) and postoperative medical complications in geriatric patients with distal femur fractures. [10] (10.1016/j.injury.2016.05.024)
  • [L4] Minimally-invasive internal fixation of distal extra-articular fractures of the femur with a locking plate is an elegant but difficult technique that associates the principles of internal fixation in a closed fracture site with assembly stability. [11] (10.1016/j.otsr.2010.11.004)
  • [L3] Distal femur fractures treated with retrograde intramedullary nails or lateral locked plates showed no notable differences in revision surgery rates, radiographic healing, or qualitative clinical outcomes. [13] (10.5435/jaaos-d-25-00575)
  • [L4] Distal femoral fracture shows highly variable epidemiology, with AO/OTA type A fractures mainly involving elderly, relatively dependent female subjects. [14] (10.1016/j.otsr.2014.06.004)
  • [L3] Despite modern treatment, the patient-reported outcomes of lower limb long bone shaft fractures do not return to normal at one year. [15] (10.1016/j.injury.2014.06.025)
  • [L4] Plating has a definite place in the management of those fractures of the shaft of the femur that are unsuitable for medullary nailing. [16] (10.1016/0020-1383(85)90078-6)
  • [L3] Distal femoral periprosthetic fractures have a high morbidity and mortality. [17] (10.1016/j.arth.2016.12.013)
  • [L4] In this series of 55 patients with periprosthetic distal femur fractures treated with precontoured lateral locking plates, 18% developed nonunion and the overall complication rate was 24%. [18] (10.1016/j.injury.2020.05.009)
  • [L5] Bilateral closed femoral shaft fractures should be treated with caution due to the increased risk of complications. [19] (10.1016/s0020-1383(15)30041-3)
  • [L4] The long-term results of indirect reduction techniques of distal femoral fractures treated with the condylar plate were good to excellent in 82% of cases. [20] (10.1016/j.injury.2008.08.046)
  • [L4] [22] (10.1016/j.injury.2012.03.023)
  • [L4] C-type distal femur fractures can present with four main fracture patterns, most containing a central sagittal intercondylar split with a high proportion of medial or lateral coronal fracture lines. [23] (10.5435/jaaos-d-23-01254)
  • [L4] The review identified distinct zones of compromised blood supply in the femur and tibia, particularly in the middle and lower segments, which may predispose these areas to an increased risk of non-union following a fracture. [24] (10.1016/j.injury.2014.09.006)
  • [L4] Complete clinical and radiological union was achieved in all cases in a mean duration of 5.2 months. [25] (10.1016/s0020-1383(17)30490-4)
  • [L3] The ROM of hip and knee returns to normal over time, regardless of the nailing method used. [27] (10.1016/j.injury.2012.03.011)
  • [L2] While the acute fracture and complications may have resolved clinically, the detrimental effect on a patient's quality of life persists up to 12 months after the injury. [28] (10.1302/0301-620x.100b9.bjj-2017-1488.r1)
  • [L4] All fractures progressed to clinical and radiological union at final follow-up. [29] (10.1016/j.injury.2015.08.008)
  • [L3] In a distal femur fracture with a simple fracture pattern, using positional screws to sustain the reduced interfragmentary gap may achieve a more rapid union by reducing fracture gap. [30] (10.1016/j.injury.2016.10.034)
  • [L4] Surveillance radiographs in the first 12 weeks after tibial and femoral intramedullary fixation do not result in changes in management. [32] (10.5435/jaaosglobal-d-23-00069)
  • [L3] The two minimally invasive implants used were good in terms of technique and outcome for treatment of distal femoral fractures and did not differ significantly for epidemiology, fracture type, conversion procedures, infection rate, malalignments, and subjective and objective findings at the 1-year followup. [33] (10.1097/01.blo.0000141935.86481.ba)
  • [L1] ORIF and DFR for the treatment of periprosthetic distal femur fractures have similar surgical complication and reoperation profiles. [34] (10.1016/j.arth.2023.01.044)
  • [L3] While prospective data is required, rIMN does appear to be an appropriate treatment for complete articular distal femur fractures with a potentially decreased rate of nonunion. [35] (10.1016/j.injury.2021.11.037)
  • [L1] Double plate fixation for comminuted fractures of the distal femur can improve knee mobility at 6 months postoperatively, reduce overall postoperative complications, and decrease the incidence of malunion healing. [37] (10.1530/eor-23-0160)
  • [L5] Delayed unions and non-unions of fractures continue to be of great interest and are associated with significant patient morbidity. [38] (10.1016/j.injury.2017.04.019)
  • [L4] In elderly patients, double plate fixation for distal femoral fractures is an useful method for several advantages such as adequate exposure, easy manipulation, anatomical reduction and stable fixation. [39] (10.1186/s13018-022-02944-6)
  • [L3] [43] (10.1007/s00402-019-03172-0)
  • [L4] The failure rate of treatment of nonunions of the distal femur with internal fixation and autologous bone grafting remains high at 20% to 30%. [47] (10.2106/jbjs.23.00985)
  • [L3] Closed fracture and regular follow up were determining factors for better functional outcomes. [48] (10.1186/s13018-024-05054-7)
  • [L4] Treating neglected femoral diaphyseal fractures with a two-stage surgery is a satisfactory therapy showing reliable bony union. [49] (10.1016/j.injury.2013.03.019)
  • [L5] Common indications for dual-implant fixation include nonunion treatment and comminuted fractures with bone loss. [52] (10.5435/jaaos-d-24-01222)
  • [L4] [54] (10.1016/s0020-1383(03)00262-6)
  • [L3] IMN may be a superior treatment compared with anatomical locking plates for fractures of the distal femur. [55] (10.1302/0301-620x.98b6.36826)
  • [L4] PROMs provide insight into the natural history of the patient experience after tibial fracture but have limited utility as a measure of structural bone healing. [56] (10.2106/jbjs.18.01139)
  • [L1] In this multicenter randomized trial of adult patients with an AO/OTA type 33A or 33C distal femoral fracture, similar clinical and radiographic healing outcomes were observed in the FCL and standard fixation groups. [57] (10.2106/jbjs.23.01390)
  • [L5] Operative stabilization of distal femur fractures can be successfully and equally well achieved using either a monoaxial or a polyaxial locking plate. [58] (10.1186/1471-2474-15-369)
  • [L4] This technique is a reasonable and safe treatment option for femoral fractures associated with vascular injury. [60] (10.1016/j.injury.2020.03.044)
  • [L3] Osteoporosis influences the late period of fracture healing in femoral shaft fractures treated with intramedullary nailing. [63] (10.1016/j.injury.2008.10.035)
  • [L4] Radiographic evidence of fracture union was observed at an average of 4.75±1.75 months (range 3 to 8 months). [67] (10.1016/s0020-1383(14)70013-0)
  • [L4] A simple classification system connecting fracture patterns to treatment algorithms can assist surgeons in obtaining optimal clinical results. [99] (10.1016/j.arth.2006.12.054)
  • [L4] Ilizarov fixator was an effective treatment modality of open comminuted distal femur fractures with high union rate, adequate alignment and satisfactory functional outcomes. [106] (10.1016/j.injury.2019.05.011)
  • [Paper] The article reviews various techniques proposed for managing aseptic diaphyseal long bone non-unions that do not require removal of the existing nail, noting that while some methods like augmentation plating show high success rates, evidence for others such as ultrasound and electrostimulation remains inconclusive or weak. [107] (10.1016/j.injury.2017.04.022)
  • [L4] The results demonstrated satisfactory healing for the treatment of diaphyseal nonunions of the femur and tibia. [111] (10.1016/j.injury.2008.07.029)
  • [L4] This indicates that NUSS could be an appropriate scoring system to classify and stratify non-unions and to enable the surgeon to choose the correct treatment. [114] (10.1016/j.injury.2014.10.030)
  • [L4] Treatment of coronal plane distal femur fractures (Busch-Hoffa fractures) should be approached in a systematic manner using a proposed algorithmic treatment protocol to guide treatment, approach, and fixation based on the modified Letenneur classification. [116] (10.1016/j.injury.2018.06.008)
  • [L4] The use of the LISS in combination with autogenous bone grafting adequately addresses nonunion fixation of the distal femur in elderly patients, achieving bone healing and preservation of knee function even in severe osteoporosis with substantial bone defects. [119] (10.1007/s00402-006-0102-0)
  • [L4] [122] (10.1016/j.injury.2013.03.018)
  • [L4] The authors advocate a minimum of 10 cortices of fixation above and below the fracture and recommend bone grafting if the soft tissue envelope is violated. [125] (10.1016/j.arth.2010.07.002)
  • [L5] In case of non-union, its treatment should consider preservation of the blood supply at the fracture site. [130] (10.1016/s0020-1383(15)30044-9)
  • [L4] Distal femur intra-articular coronal plane fractures can yield large anterior and posterior condylar fracture fragments of either the medial condyle, lateral condyle, or both condyles. [180] (10.1016/j.injury.2020.11.061)
  • [L2] DCE-MRI at 26 weeks follow-up predicts non-union consolidation with a sensitivity of 75% and specificity of 87%. [186] (10.1016/j.injury.2017.01.021)

See Also

References

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For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

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