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Periprosthetic fracture (knee)

78 citationsUpdated Sep 2026
Illustration: knee

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

Overview

Periprosthetic fractures around the knee present a significant surgical challenge, predominantly affecting elderly patients with reduced bone quality and revealing a high complication rate [8]. These injuries are uncommon but notable complications that require intraoperative recognition and attentiveness to preoperative patient and surgical risk factors [25]. Intraoperative periprosthetic fracture of the tibia was fourteenfold more likely in revision total knee arthroplasties (TKAs) compared with primary TKAs [5]. Appropriate management of periprosthetic tibial fractures depends on careful scrutiny of radiographs and a thorough clinical history to exclude infection [1].

Periprosthetic knee fractures are predominantly treated with open reduction and internal fixation (ORIF) rather than revision TKA [9]. Revision TKA is considered for periprosthetic fractures associated with loose or malaligned implants, with or without severe bone loss [10]. While operative fixation of periprosthetic distal femoral fractures after TKA continues to be challenging with loss of reduction and high failure rates [11], outcomes of surgical treatment for periprosthetic and non-periprosthetic distal femur fractures are similar [14]. Periprosthetic distal femoral fracture after TKA worsens functional outcomes at the medium term, but arthroplasty complication and survival rates were similar in both groups [6].

The treatment of periprosthetic fractures of the femur in patients with total knee arthroplasties can result in a significant complication rate due to the challenges present [4]. Both plate and nail fixation present unique benefits and pitfalls for treating periprosthetic fractures about a well-fixed prosthesis [16]. Locking plates offer a viable treatment option for periprosthetic femoral fractures around well-fixed hip and knee implants [17]. Surgical treatment of periprosthetic supracondylar femoral fractures following TKA with long retrograde intramedullary nailing resulted in high union rates and encouraging functional outcomes [13]. The authors cautiously recommend the use of a supracondylar intramedullary nail for selected patients with supracondylar fractures of the femur proximal to a total knee arthroplasty, noting advantages such as decreased operative time and the ability to start early range-of-motion exercises [136]. Regardless of which implant is used, the proper application is essential in management of periprosthetic supracondylar femur fractures above TKA [12].

Anatomy & Pathophysiology

Osseous Anatomy

The knee joint comprises the distal femur, proximal tibia, and patella [41]. The medial femoral condyle is larger and projects farther posteriorly and distally than the lateral condyle [58]. Conversely, the lateral femoral condyle projects farther anteriorly and is wider in the medial-lateral direction [58]. The tibial articular surface slopes 7° to 10° in the sagittal plane [58], with a mean posterior slope of 10.7° on the medial plateau and 7.2° on the lateral plateau [63]. The medial tibial plateau is larger than the lateral plateau and is concave in both frontal and sagittal planes [58]. The lateral tibial plateau is smaller, more circular, concave in the frontal plane, and convex in the sagittal plane [58]. The patella is the largest sesamoid bone in the body, with a mean thickness of 2.5 cm [58, 63]. Its articular surface features a vertical central ridge separating the broader lateral facet from the medial facet, along with a smaller medial facet known as the odd facet [58].

Ligamentous Anatomy

The anterior cruciate ligament (ACL) prevents anterior translation and rotation of the tibia on the femur [41]. The posterior cruciate ligament (PCL) prevents posterior subluxation of the tibia on the femur [41]. The medial collateral ligament stabilizes the knee against valgus stresses [41], while the lateral collateral ligament serves as the main stabilizer against varus stress [41]. The ACL consists of 90% type I collagen and 10% type III collagen [58, 63]. It has a mean length of 33 mm and a mean midsubstance width of 11 mm [58, 63]. The femoral attachment is a semicircular area on the posteromedial aspect of the lateral femoral condyle [58, 63], while the tibial attachment is a broad, irregular, oval-shaped area between the medial and lateral tibial spinous processes [58]. The PCL is the largest intra-articular ligament, averaging 38 mm in length with a mean midpoint diameter of 13 mm [71]. It contains two distinct bundles defined by femoral insertion: an anterolateral (AL) bundle and a posteromedial (PM) bundle [71]. The AL bundle is larger, comprising 85% of the PCL's cross-sectional area [71]. The PCL inserts onto a midline depression on the tibia 10 to 15 mm below the level of the medial and lateral tibial plateaus [71]. Meniscofemoral ligaments are present in at least one form in 93% of knees [71]. Regarding bundle tension, the ACL anteromedial bundle is tight in knee flexion while the posterolateral bundle is tight in knee extension [63]. Similarly, the PCL anterolateral bundle is tight in knee flexion and the posteromedial bundle is tight in knee extension [63].

Meniscal Anatomy

The menisci are C-shaped fibrocartilaginous disks that provide shock absorption, increase congruency between joint surfaces, enhance joint stability, and aid in the distribution of synovial fluid [41]. The medial meniscus is firmly attached to the joint capsule along its entire peripheral edge [41]. The lateral meniscus attaches to the anterior and posterior capsule but has a region posterolaterally where it is not firmly attached [41]. Consequently, 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 [41]. The lateral meniscus is larger than the medial meniscus and carries a greater share of the lateral compartment pressure [41]. Histologically, the menisci consist of type I collagen fibers arranged obliquely, radially, and vertically [63]. Vascular supply derives from the geniculate arteries, which penetrate into 20% to 30% of the peripheral medial meniscus and 10% to 25% of the peripheral lateral meniscus [63].

Vascular and Neural Anatomy

The blood supply to the knee forms an anastomosis derived from the descending geniculate artery, superior and inferior geniculate arteries, middle geniculate artery, and anterior tibial recurrent arteries [58]. The middle geniculate artery supplies both the anterior and posterior cruciate ligaments [58]. Innervation is provided by branches of the femoral nerve (L2, L3, L4), obturator nerve (L2, L3, L4), and sciatic nerve (L4, L5, S1, S2) [58]. The posterior articular branch of the tibial nerve is the largest nerve providing innervation to the intra-articular knee [58]. The popliteus artery travels through the adductor hiatus where it is relatively immobile and distally through the fibrous arch deep to the soleus muscle [68]. The common peroneal nerve travels along the posterior edge of the biceps femoris and continues distally around the fibular neck [68].

Kinematics and Biomechanics

The knee is a hinge joint incorporating both gliding and rolling, which are essential to its kinematics [59]. The "screw-home" mechanism involves the tibia externally rotating 5 degrees in the final 15 degrees of extension [59]. The greatest range of motion occurs in the sagittal plane at approximately 160° [75]. Knee rotation ranges from 45° in external rotation to 30° in internal rotation [75]. In the frontal plane, the range of motion in both abduction and adduction reaches a maximum of 10° [75]. The normal instant center of the knee joint follows a semicircular path related to the tibiofemoral surface and ligaments crossing the joint [75]. Rupture of the cruciate ligaments or disruption of the tibiofemoral surface causes a major change in the path of the instant center, leading to articular dysfunction [75]. In full extension, the knee slightly hyperextends with slight tibial external rotation while collateral and cruciate ligaments tighten to lock the knee [76]. The popliteus muscle initiates flexion by pulling the lateral femoral condyle backward while the medial femoral condyle slides forward, resulting in tibial internal rotation [76].

Pathophysiology of Periprosthetic Fracture

Higher risks of periprosthetic knee fractures are observed in non-osteoarthritis patients and/or patients who had a higher level of TKA constraint [32]. Biomechanical studies indicate that notching during femoral preparation weakens the anterior femur at the bone-component interface [86]. Anterior femoral notching decreases the fracture resistance of the distal femur but does not necessarily equate to a higher risk of supracondylar femur fracture [86]. A distal locking plate for the treatment of supracondylar fractures leads to a higher required fracture force [38]. Implantation of a constrained knee prosthesis that is not loosened does not increase the risk for a fracture [38]. The incidence of periprosthetic fracture of the distal femur in total knee arthroplasty is 0.3% to 2.5% [86]. The incidence of periprosthetic tibial fracture in primary TKA is 0.7% or less [86]. The incidence of periprosthetic tibial fracture in revision TKA is 0.9% or less [86]. The fracture line in periprosthetic fractures may be obscured by a metallic component on plain radiographs [86]. Bone scans may help identify a fracture when plain radiographs are not diagnostic [86]. Bone scans may also help identify late periprosthetic tibial fractures not seen on plain radiographs [86].

Classification

Vancouver: Developed by Duncan and Masri in 1995, this system categorizes fractures into Type A (trochanteric regions), Type B (around the stem), and Type C (distal to the stem) [33]. Type A fractures involve the trochanteric regions, specifically Ag (greater trochanter) and Al (lesser trochanter), and are generally stable [33]. Type B fractures are localized around the stem or immediately below it and are sub-classified into B1 (stable stem, adequate bone stock), B2 (unstable stem, adequate bone stock), and B3 (unstable stem, inadequate bone stock) [33]. Type C fractures occur distally to the stem [33].

Su et al.: This classification system divides periprosthetic fractures of the distal femur into three sub-types based on conventional radiographs and CT-scan [97].

AO/ASIF: This classification is used to categorize distal femoral fractures above a well-fixed total knee arthroplasty, with Type 33A fractures defined as those above a well-fixed femoral component with no evidence of loosening [44].

Other Considerations: A proposed modification to the Vancouver and SoFCOT classifications adds a type D category for interprosthetic fractures on TKR with femoral shaft extension stem [92]. A simple classification system connecting fracture patterns to treatment algorithms can assist surgeons in obtaining optimal clinical results [49]. 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 [130]. Fracture classification should guide surgical decision-making, with intraoperative Type-I fractures having 100% 2-year survivorship free of tibial component revision compared with 10% in postoperative Type-I fractures [143].

Clinical Presentation

Periprosthetic tibial fractures predominantly affect elderly patients with reduced bone quality [8]. In the setting of periprosthetic distal femoral fracture after total knee arthroplasty, functional outcomes worsen at the medium term [6]. While 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 [36].

Associated injuries are frequent with floating knee and can cause delays in surgical management and rehabilitation [45]. Patellar fracture after total knee arthroplasty with retained patella is infrequent [114]. Clinical and radiological results for patellar fracture after total knee arthroplasty with retained patella are relatively improved compared with those of patellar fracture after total knee arthroplasty with resurfaced patella [114].

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 [43].

CT: Computed tomography imaging in the axial, sagittal, and coronal planes helps visualize fracture lines and displacement, osteolytic lesions around joint arthroplasty, and cortical disruption in cases of infection or neoplasia [43]. Three-dimensional CT reconstructions may aid preoperative planning for complex intra-articular fractures and reconstitution of bone loss in joint arthroplasty [43]. Additionally, axial plane imaging of the knee can help assess the rotational alignment of components of a total knee arthroplasty in cases of patellar maltracking [43].

MRI: Magnetic resonance imaging may be used to assess the continuity of the quadriceps or patellar tendon [43]. It may also be used to assess neurovascular structures, including identifying vascular malformation or defining the location of nerves or vessels relative to popliteal cysts [43].

Bone scan: Technetium-99 (Tc-99) is a radionuclide that may help identify infection, neoplasia, occult fracture, bone healing, active phases of heterotopic ossification, implant loosening, or failure of osseointegration [43]. Gallium-67 (Ga-67) is a radionuclide that may help differentiate between aseptic and septic prosthetic loosening [43]. Increased radionuclide activity in bone may be a normal postoperative finding for up to 6 to 12 months after a fracture repair or arthroplasty [43].

Other Considerations: Age was determined to be the independent risk factor for early periprosthetic femoral fracture after total knee arthroplasty [39].

Treatment

Non-Operative

Non-surgical management is a rare option for periprosthetic knee fractures, as surgical treatment is indicated to stabilize distal femur fractures [121]. In the specific event of a patellar fracture occurring after total knee arthroplasty, conservative treatment appears to be a favorable choice [144].

Operative

Indications: Periprosthetic knee fractures are predominantly treated with open reduction and internal fixation (ORIF) rather than revision total knee arthroplasty (TKA) [9]. If the prosthesis is loose, the logical treatment is a revision operation with insertion of a femoral component with a longer stem to stabilize the fracture [93].

Surgical Approach / Technique: The distal femoral nail may be used successfully in selected cases with a periprosthetic fracture, provided careful preoperative planning is performed [15]. Fixation of periprosthetic supracondylar femoral fractures with a locking plate provides satisfactory results with a low risk of complications and additional surgeries compared with fixation with a non-locking plate [48]. A long-locking plate combined with a locking attachment plate shows favorable radiographic and clinical outcomes in patients with periprosthetic femoral fracture around an ipsilateral stem after TKA [20]. Associated osteotomy can correct rotational deformities and facilitate implantation of a moderately constrained prosthesis in deformities close to the joint [47]. For tibial fractures, a novel tibial implant has been developed to repair peri-prosthetic proximal tibia fractures, overcoming significant constraints from the tibial component of existing knee implants [22]. Ilizarov external fixation has been used for a periprosthetic tibial fracture after TKA in severe osteoporosis [29]. Circular external fixation is a safe and reliable method for periprosthetic fractures around the knee in elderly patients [117].

Implant Selection: Clinical outcomes, including nonunion and revision rates, are similar in patients who undergo locking compression plate and retrograde intramedullary nail fixation for periprosthetic supracondylar femoral fracture following TKA [108]. The use of either intramedullary nail or locking plate fixation for supracondylar periprosthetic fractures provides comparable clinical outcomes [120]. The use of a distal locking plate for the treatment of supracondylar fractures leads to a higher required fracture force, and implantation of a constrained knee prosthesis that is not loosened does not increase the risk for a fracture [38]. Distal femoral replacement provides a functionally acceptable knee with few complications requiring re-operation, though complication rates are high and functional outcomes are relatively poor due to patient demographics [31].

Other Considerations: Closed treatment of a fracture of the femoral shaft is associated with many problems, including medical complications secondary to prolonged bed rest, potential loss of motion of the hip or knee, and non-union or malunion [93]. Periprosthetic fractures can be very challenging for an orthopedic surgeon, and sometimes, the best surgical solution cannot be found in the textbooks [18]. The survey highlights the need for further studies to investigate best treatment and establish discrete indications for single versus dual-implant fixation [106].

Outcomes and Complications: Delayed unions and non-unions of fractures continue to be of great interest and are associated with significant patient morbidity [54]. 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 [50]. The risk of non-union, delayed union, infection and additional procedures is high in segmental tibial fractures [55]. In case of non-union, its treatment should consider preservation of the blood supply at the fracture site [146]. Future strategies should focus on prevention in high-risk populations such as polytrauma patients treated with external fixation [148]. 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 [111]. Comparable low incidences of periprosthetic tibial fractures can be achieved in cementless and cemented unicompartmental knee arthroplasty [24].

Complications

General Complication Burden: Periprosthetic fractures around total knee arthroplasties pose a significant surgical challenge [3]. Treatment of periprosthetic femoral fractures in patients with total knee arthroplasties can result in a significant complication rate [4]. The annual incidence of proximal and distal periprosthetic fractures has increased significantly, with high rates of mortality and return to the operating room within 1 year [150].

Fixation-Specific Complications: In a multicenter 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% [34]. Following additional surgery, 49 of 55 patients (89%) in this series went on to heal [34]. Regression analysis of these 55 patients identified no patient or surgical variables as independent risk factors for nonunion [34]. Peri-implant fracture could occur in patients with rheumatoid arthritis or periprosthetic fracture after TKA following locking plate fixation for osteoporotic distal femur fractures [27].

Recovery

Functional Outcomes and Quality of Life: Periprosthetic distal femoral fracture following total knee arthroplasty worsens functional outcomes at the medium term [6]. Despite this functional decline, arthroplasty complication and survival rates remain similar in patients with periprosthetic distal femoral fracture compared to those without [6]. Patient-reported outcomes for lower limb long bone shaft fractures do not return to normal at one year despite modern treatment [124]. The detrimental effect on a patient's quality of life persists up to 12 months after tibial fracture and complications, even if the acute fracture and complications have resolved clinically [36]. Patient-reported outcome measures provide insight into the natural history of the patient experience after tibial fracture but have limited utility as a measure of structural bone healing [28].

Union and Non-Union Rates: In a series of 55 patients with periprosthetic distal femur fractures treated with precontoured lateral locking plates, the overall rate of nonunion was 18% [34]. The total complication rate in this cohort was 24% [34]. After additional surgery, 49 of 55 patients (89%) went on to heal [34]. No patient demographic or injury variables were identified as independent risk factors for nonunion in a regression analysis of these 55 patients [34]. Delayed union or nonunion occurred in 60 of 485 patients (12.4%) with tibial or femoral shaft fractures [151]. At a mean of 4 years after injury, fracture-related infection and nonunion became chronic conditions in nearly a quarter of participants who experienced these complications, regardless of reintervention [40]. Delayed unions and non-unions of fractures are associated with significant patient morbidity [54].

Healing Timelines: Radiographic evidence of fracture union was observed at an average of 4.75±1.75 months (range 3 to 8 months) in femoral shaft non-unions treated with autologous concentrated bone-marrow grafting after locked intramedullary nailing [57]. 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 [154]. Time to radiographic union and full weight-bearing did not differ significantly between external fixation and locked intramedullary nailing groups for tibial shaft fractures [152]. However, unprotected weight-bearing was achieved earlier in the intramedullary nail group compared to the external fixation group for tibial shaft fractures [152].

Surgical Outcomes and Complications: Surgical treatment of periprosthetic supracondylar femoral fractures following total knee arthroplasty with long retrograde intramedullary nailing resulted in high union rates and encouraging functional outcomes [13]. Operative fixation of periprosthetic distal femoral fractures after total knee arthroplasty continues to be challenging with loss of reduction and high failure rates [11]. A long-locking plate combined with a locking attachment plate showed favorable radiographic and clinical outcomes in patients with periprosthetic femoral fracture around an ipsilateral stem after total knee arthroplasty [20]. 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 [56].

Other Considerations: Closed fracture and regular follow-up were determining factors for better functional outcomes in distal femur fractures treated with open reduction and internal fixation [126].

Key Evidence

  • [L5] Appropriate management of periprosthetic tibial fractures depends on careful scrutiny of radiographs and a thorough clinical history to exclude infection. [1] (10.5435/jaaos-d-16-00387)
  • [L5] The management of periprosthetic fractures around the knee remains a challenging problem. [2] (10.1097/01.blo.0000214417.29335.19)
  • [L4] Periprosthetic fractures around total knee arthroplasties pose a significant surgical challenge that can mostly be managed with osteosynthesis and salvage of the replacement. [3] (10.1302/0301-620x.98b11.bjj-2016-0029.r1)
  • [L4] The treatment of periprosthetic fractures of the femur in patients with total knee arthroplasties can result in a significant complication rate due to the challenges present. [4] (10.1016/j.arth.2011.08.007)
  • [L3] Intraoperative periprosthetic fracture of the tibia was fourteenfold more likely in revision TKRs compared with primary TKRs. [5] (10.2106/jbjs.24.01407)
  • [L3] Periprosthetic distal femoral fracture after TKA worsens functional outcomes at the medium term, but arthroplasty complication and survival rates were similar in both groups. [6] (10.1016/j.arth.2013.03.007)
  • [L4] We had a satisfactory outcome following individualised treatment of interprosthetic femoral fractures following ipsilateral hip and knee joint replacement. [7] (10.1016/j.injury.2010.08.020)
  • [L4] Periprosthetic tibial fractures predominantly affect elderly patients with reduced bone quality and reveal a high complication rate. [8] (10.1186/s12891-018-2250-0)
  • [L3] Periprosthetic knee fractures are predominantly treated with ORIF rather than revision total knee arthroplasty (TKA), whereas periprosthetic hip fractures are predominantly treated with revision total hip arthroplasty (THA) rather than ORIF. [9] (10.2106/jbjs.23.00868)
  • [L5] Revision TKA is considered for periprosthetic fractures associated with loose or malaligned implants, with or without severe bone loss. [10] (10.5435/jaaos-d-15-00680)
  • [L3] Operative fixation of periprosthetic distal femoral fractures after TKA continues to be challenging with loss of reduction and high failure rates. [11] (10.1016/j.injury.2012.01.025)
  • [L3] Regardless of which implant is used, the proper application is essential in management of periprosthetic supracondylar femur fractures above TKA. [12] (10.1007/s00402-015-2374-8)
  • [L4] Surgical treatment of periprosthetic supracondylar femoral fractures following TKA with long retrograde intramedullary nailing resulted in high union rates and encouraging functional outcomes. [13] (10.1007/s00402-013-1890-7)
  • [L3] Outcomes of surgical treatment for periprosthetic and non-periprosthetic distal femur fractures are similar. [14] (10.1186/s13018-019-1204-z)
  • [L4] The DFN may be used successfully in selected cases with a periprosthetic fracture, provided careful preoperative planning is performed. [15] (10.1016/s0020-1383(03)00191-8)
  • [L4] Both plate and nail fixation present unique benefits and pitfalls for treating periprosthetic fractures about a well-fixed prosthesis. [16] (10.1016/j.otsr.2016.11.018)
  • [L4] Locking plates offer a viable treatment option for periprosthetic femoral fractures around well-fixed hip and knee implants. [17] (10.1016/j.arth.2010.07.002)
  • [L4] Periprosthetic fractures can be very challenging for an orthopedic surgeon, and sometimes, the best surgical solution cannot be found in the textbooks. [18] (10.1016/j.arth.2011.06.037)
  • [L4] Megaprosthesis represent a viable treatment option in patients affected by distal femoral fractures because they allow immediate weight-bearing, shorter hospital stay, a fast recovery of knee function and activities of daily living. [19] (10.1016/j.injury.2019.08.011)
  • [L4] Long-locking plate combined with LAP showed favorable radiographic and clinical outcomes in patients with periprosthetic femoral fracture around ipsilateral stem after TKA. [20] (10.1186/s12891-023-06726-x)
  • [L4] Periprosthetic fracture fixation can be performed as part of a standardised less invasive strategy, but the minimally invasive technique should be the preferred treatment. [21] (10.1016/j.injury.2012.10.035)
  • [L4] A novel tibial implant has been developed to repair peri-prosthetic proximal tibia fractures which overcomes significant constraints from the tibial component of existing knee implant. [22] (10.1016/j.injury.2018.01.032)
  • [L4] This technique should be considered in patients with low periprosthetic femur fractures associated with metaphyseal comminution and loss of bone stock due to its biologic and mechanical advantages. [23] (10.1016/j.arth.2007.05.054)
  • [L1] Comparable low incidences of periprosthetic tibial fractures in cementless and cemented UKA can be achieved. [24] (10.1007/s00167-021-06449-3)
  • [L5] Intraoperative periprosthetic fractures are uncommon but notable complications requiring intraoperative recognition and attentiveness to preoperative patient and surgical risk factors. [25] (10.5435/jaaos-d-23-00153)
  • [L4] However, peri-implant fracture could occur in patients with RA or periprosthetic fracture after TKA. [27] (10.1016/j.otsr.2017.08.008)
  • [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. [28] (10.2106/jbjs.18.01139)
  • [Case_report] To the best of our knowledge, this is the first report in which Ilizarov external fixation has been used for a periprosthetic tibial fracture after TKA. [29] (10.1186/s12891-020-3176-x)
  • [L4] It provides a functionally acceptable knee with few complications requiring re-operation, though complication rates are high and functional outcomes are relatively poor due to patient demographics. [31] (10.1016/j.injury.2013.10.032)
  • [L3] Higher risks were observed in non-osteoarthritis patients and/or patients who had a higher level of TKA constraint. [32] (10.1016/j.arth.2024.05.033)
  • [L4] [33] (10.1016/j.injury.2013.09.028)
  • [L4] [34] (10.1016/j.injury.2020.05.009)
  • [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. [36] (10.1302/0301-620x.100b9.bjj-2017-1488.r1)
  • [L5] A distal locking plate for the treatment of supracondylar fractures leads to a higher required fracture force, and implantation of a constrained knee prosthesis that is not loosened does not increase the risk for a fracture. [38] (10.1007/s00264-012-1697-0)
  • [L3] This study determined that age was the independent risk factor for early periprosthetic femoral fracture. [39] (10.1186/s12891-021-04875-5)
  • [L4] At a mean of 4 years after injury, fracture-related infection and nonunion became chronic conditions in nearly a quarter of the participants who experienced these complications, regardless of reintervention. [40] (10.2106/jbjs.22.00016)
  • [L4] [44] (10.1016/j.injury.2008.10.020)
  • [L4] Associated injuries are frequent with floating knee and can cause delays in surgical management and rehabilitation. [45] (10.1186/1471-2474-10-7)
  • [L4] Associated osteotomy can correct rotational deformities and facilitate implantation of moderately constrained prosthesis in deformities close to the joint. [47] (10.1016/j.otsr.2010.06.010)
  • [L3] Fixation of periprosthetic supracondylar femoral fractures with a locking plate provided satisfactory results with a low risk of complications and additional surgeries compared with fixation with a non-locking plate. [48] (10.1007/s00167-013-2572-2)
  • [L4] A simple classification system connecting fracture patterns to treatment algorithms can assist surgeons in obtaining optimal clinical results. [49] (10.1016/j.arth.2006.12.054)
  • [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. [50] (10.1016/s0020-1383(15)30049-8)
  • [L5] Delayed unions and non-unions of fractures continue to be of great interest and are associated with significant patient morbidity. [54] (10.1016/j.injury.2017.04.019)
  • [L4] The risk of non-union, delayed union, infection and additional procedures is high as seen in this series of patients. [55] (10.1016/s0020-1383(02)00393-5)
  • [L4] All fractures progressed to clinical and radiological union at final follow-up. [56] (10.1016/j.injury.2015.08.008)
  • [L4] Radiographic evidence of fracture union was observed at an average of 4.75±1.75 months (range 3 to 8 months). [57] (10.1016/s0020-1383(14)70013-0)
  • [L4] The study proposes adding a type D category to the Vancouver and SoFCOT classifications for interprosthetic fractures on TKR with femoral shaft extension stem. [92] (10.1016/j.otsr.2011.07.009)
  • [L4] [97] (10.1007/s00402-013-1730-9)
  • [L5] The survey highlights the need for further studies to investigate best treatment and establish discrete indications for single versus dual-implant fixation. [106] (10.5435/jaaos-d-24-01222)
  • [L1] Clinical outcomes, including nonunion and revision rates, were similar in patients who underwent locking compression plate and retrograde intramedullary nail fixation for periprosthetic supracondylar femoral fracture following TKA. [108] (10.1007/s00167-016-4050-0)
  • [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. [111] (10.1007/s00402-006-0102-0)
  • [L4] Patellar fracture after TKA with retained patella is infrequent, with relatively improved clinical and radiological results compared with those of patellar fracture after TKA with resurfaced patella reported in the literature. [114] (10.1016/j.arth.2021.03.053)
  • [L4] Circular external fixation is a safe and reliable method for periprosthetic fractures around the knee in elderly patients. [117] (10.1186/s12891-020-03352-9)
  • [L3] The use of either IM nail or locking plate fixation for supracondylar periprosthetic fractures provides comparable clinical outcomes. [120] (10.1016/j.arth.2016.06.056)
  • [L4] Surgical treatment is indicated to stabilize distal femur fractures as non-surgical treatment is a rare option. [121] (10.1016/j.otsr.2012.10.014)
  • [L3] Despite modern treatment, the patient-reported outcomes of lower limb long bone shaft fractures do not return to normal at one year. [124] (10.1016/j.injury.2014.06.025)
  • [L3] Closed fracture and regular follow up were determining factors for better functional outcomes. [126] (10.1186/s13018-024-05054-7)
  • [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. [130] (10.1016/j.injury.2014.10.030)
  • [L4] The authors cautiously recommend the use of a supracondylar intramedullary nail for selected patients with supracondylar fractures of the femur proximal to a total knee arthroplasty, noting advantages such as decreased operative time and the ability to start early range-of-motion exercises. [136] (10.2106/00004623-199506000-00013)
  • [L4] This commentary reinforces that fracture classification should guide surgical decision-making, noting that intraoperative Type-I fractures have 100% 2-year survivorship free of tibial component revision compared with 10% in postoperative Type-I fractures, while highlighting the need for future research on modern fixation techniques and functional outcomes. [143] (10.2106/jbjs.25.00234)
  • [L3] In the event that a fracture does occur, conservative treatment seems a favorable choice. [144] (10.1016/j.arth.2012.04.022)
  • [L5] In case of non-union, its treatment should consider preservation of the blood supply at the fracture site. [146] (10.1016/s0020-1383(15)30044-9)
  • [L3] Future strategies should focus on prevention in high-risk populations such as polytrauma patients treated with external fixation. [148] (10.1016/j.injury.2014.12.018)
  • [L4] The annual incidence of proximal and distal periprosthetic fractures has increased significantly, with high rates of mortality and return to the operating room within 1 year, emphasizing the need for better prevention strategies and thoughtful surgical management. [150] (10.1097/corr.0000000000002686)
  • [L3] Delayed union/nonunion occurred in 60/485 patients (12.4%). [151] (10.1186/s12891-026-10074-x)
  • [L1] Time to radiographic union and full weight-bearing did not differ significantly between groups, but unprotected weight-bearing was achieved earlier in the intramedullary nail group. [152] (10.1007/s00402-004-0768-0)
  • [L4] Complete clinical and radiological union was achieved in all cases in a mean duration of 5.2 months. [154] (10.1016/s0020-1383(17)30490-4)

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