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Trauma & Fractures

Hip fractures and dislocations — management of fragility intracapsular/intertrochanteric fractures versus high-energy Pipkin and acetabular injuries.

Overview

Femoral neck stress fractures may not require surgical intervention if fracture location and severity permit individualized non-operative management [1]. In contrast, displaced and unstable fresh femoral neck fractures in adults carry a higher incidence of complications when treated with internal fixation using fully threaded cannulated compression screws [11]. For ipsilateral multi-level femoral fractures, the rendezvous technique with distal-to-proximal stabilization is preferred, involving initial damage control orthopedics followed by staged definitive fixation [60]. Pathologic hip fractures result in significantly higher complication rates than native hip fractures after surgical treatment, suggesting that guidelines for native hip fractures may not be generalizable for pathologic hip fractures [61].

Traumatic hip dislocation outcomes are largely driven by the time from injury to reduction and associated injuries [5]. The Pipkin Classification of femoral head fractures is prognostically useful, as patients with Types 1 and 2 fractures generally have better outcomes than those with Types 3 and 4 fractures [2]. For pertrochanteric hip fractures, other fracture-recovery outcomes were similar when comparing teriparatide to risedronate [4].

Management of hip fractures in older adults is guided by the AAOS Clinical Practice Guideline, which includes 16 recommendations and three option statements to assist orthopaedic surgeons and qualified physicians managing patients older than 55 years [12]. In tibial trauma, recent data demonstrate better outcomes with internal fixation methods in most open tibial fractures, while external fixation remains an appropriate choice for more severe injuries [47]. Salvage of failed internal fixations of intertrochanteric femoral fractures with properly selected implants and profound techniques can lead to satisfactory clinical outcomes [51].

Anatomy & Pathophysiology

Osseous Morphology and Biomechanics

Femoral neck fractures in young and middle-aged adults exhibit significant morphological diversity and complexity [63]. In Arctic populations, hip geometry suggests a delicate balance that differs from European data [32]. Men possess higher trabecular bone mechanical property values at the moment of fragility hip fracture occurrence compared to women [68]. The morphology of the proximal femur and pelvis does not differ in several radiological parameters between patients sustaining a periprosthetic femoral fracture (PFF) after cementless short stem versus straight stem total hip arthroplasty (THA) [76].

Implant Biomechanics and Stability

The femoral neck system (FNS) contributes to improved hip joint function through structural stability and advantages in resisting femoral head varus [49]. The FNS demonstrates excellent biomechanical properties, showing significantly higher overall construct stability compared to cannulated compression screws in younger patients [55]. However, the biomechanical performance of the FNS is fracture-type-dependent, necessitating angle-specific optimization [58]. When the Pauwels angle is 30°, a positive buttress configuration is more stable than a negative buttress from a biomechanical perspective [57]. Intraoperative mechanical injury of the femoral neck or malpositioning of the femoral component may lead to changes in loading patterns, resulting in acute and chronic biomechanical femoral neck fractures [3].

Hip Instability and Dysplasia

Hip microinstability is characterized by abnormal femoral head micromotion within the acetabulum, leading to cartilage damage and osteoarthritis [50]. This condition is often associated with acetabular dysplasia or femoroacetabular impingement syndrome [50]. Congenital subluxation and dislocation of the hip are distinct clinical entities sharing a common etiology of genetic or biomechanical dysplasia [65]. Early treatment of congenital hip dysplasia during infancy, prior to weight-bearing, is critical to enhance growth potential and prevent secondary pathological changes [65]. Every child with spastic lower limbs should be regarded as having potential subluxation or dislocation of the hip if pathomechanics are understood [69].

Surgical and Clinical Context

Stability of the hip after proximal femoral endoprosthesis (PFA) is influenced by variables associated with the patient, the pathology, the surgical technique, and the implant [78]. Impingement-type sports are most frequently associated with hip injuries [67]. Hip surveillance programmes aim to identify and address hip pathology proactively through serial radiological and clinical assessments to standardize care, reduce hip dislocation incidence, and prevent the need for salvage procedures [80].

Classification

Pipkin: This system classifies femoral head fractures and is prognostically useful; patients with Types 1 and 2 fractures generally experience better outcomes than those with Types 3 and 4 fractures [2]. A novel classification system using CT scanning also guides treatment for femoral head fracture-dislocations [22].

Vancouver: This classification guides the correct approach for periprosthetic fractures: B1 fractures are treated by fixation, B2 by revision with a long stem, and B3 by complex reconstruction or prosthetic replacement [48]. The Unified Classification System (UCS) is unsatisfactory for classifying periprosthetic femoral fractures around polished taper-slip stems, demonstrating considerably lower reliability and validity than previously described for other stem types [33]. Periprosthetic femoral fractures occur at different rates at different times depending on the method of fixation [6].

Judet and Letournel: The original classification system is difficult to apply to the modern spectrum of acetabular fractures, particularly in older patients with low-energy injuries [44]. Among the three-column classification, quadrilateral plate fractures are commonly observed in type B and C acetabular fractures [39].

AO/OTA: Unstable intertrochanteric femur fractures with a preoperative classification of AO type 31 A3 can be expected to have worse results than A2 ITF fractures [35].

Other Considerations: Stress fractures are classified as low-risk or high-risk injuries [7]. Low-risk stress fractures generally respond to activity modification [7], whereas high-risk stress fractures have a propensity to develop into chronic injuries and require more aggressive treatment [7]. Atypical tensile-sided femoral neck stress fractures may not require surgical intervention if fracture location and severity allow for individualized treatment [1]. Intraoperative mechanical injury of the femoral neck or malpositioning of the femoral component can lead to changes in loading patterns resulting in acute and chronic biomechanical femoral neck fractures [3]. A proposed novel classification system for femoral neck fracture combined with anterior dislocation of the femoral head can likely identify all injury patterns [30]. Fractures of the femoral shaft in children in the United States have a different epidemiology than that described in earlier Scandinavian reports [27].

Clinical Presentation

History: The clinical presentation varies significantly by fracture etiology and patient demographics. Spontaneous bilateral femoral neck fractures may present with low serum vitamin D levels, where early diagnosis can prevent displacement and avoid surgical intervention [15]. Stress fractures are categorized as low-risk or high-risk injuries [7]. Low-risk variants generally respond to activity modification, whereas high-risk fractures possess a propensity to become chronic injuries, necessitating more aggressive treatment [7]. In the context of atypical tensile-sided femoral neck stress fractures, surgical intervention may be omitted if fracture location and severity permit individualized non-operative management [1]. Periprosthetic femoral fractures manifest at varying rates and times depending on the specific method of fixation employed [6].

Inspection and Palpation: In pediatric trauma, inspection must prioritize the recognition of complications such as compartment syndrome and nonaccidental trauma [20]. Effective management requires careful casting and timely intervention for open fractures, tailored to the patient’s age and injury severity [24]. In acute settings, orthopaedic surgeons in Norway have demonstrated failures in reporting correct data on pathologic fractures and corresponding cancer diagnoses, highlighting a gap in thorough clinical documentation [23].

Range-of-Motion and Stability: Displaced and unstable femoral neck fractures are associated with a higher incidence of complications, indicating significant instability [11]. Intraoperative mechanical injury to the femoral neck or malpositioning of the femoral component alters loading patterns, potentially leading to acute and chronic biomechanical femoral neck fractures [3]. Femoral head fracture-dislocations present with well-tolerated symptoms in 94% of cases, though osteoarthritis develops in 43.7% of these instances [22].

Special Tests and Classification: Femoral head fractures are classified into types 1 and 2, which generally carry better prognoses than types 3 and 4 [2]. A novel classification system utilizing CT scanning guides treatment for femoral head fracture-dislocations [22]. For hip fractures in older adults, the AAOS Clinical Practice Guideline provides 16 recommendations and three option statements for patients older than 55 years [12]. Additionally, the AAOS Evidence-Based Guideline offers diagnosis and treatment recommendations based on systematic reviews for hip fractures in the elderly [31].

Red-Flag Patterns: Combined acetabulum and pelvic ring injuries represent a critical gap in outcomes data, as data exist for isolated injuries but not for combined patterns [21]. Blunt trauma injuries require physicians to stay current with new technology to hasten diagnosis and determine preferred management [36]. In in-patient trauma surgery, a treatment algorithm for diagnosing and treating osteoporosis helps systematically identify high-risk patients [34].

Investigations

Plain radiography: Careful evaluation of preoperative radiographs is recommended to rule out intra-articular penetration by bone fragments during intramedullary nailing of the femur [83]. High-quality biplanar imaging during the procedure and postoperative full-length radiographs further support this assessment [83]. In pelvic trauma, accurate assessment of imaging and determination of instability are critical for selecting the appropriate treatment course [75]. Orthopaedic surgeons in Norway failed to report correct data on pathologic fractures and the corresponding cancer diagnosis in an acute setting for many patients [23].

MRI: Magnetic resonance imaging is recommended for liberal use in detecting knee injuries in patients experiencing high-energy traumatic ipsilateral hip dislocation that are not discoverable by history and physical examination alone [53]. Rapid limited-sequence MRI of the pelvis identified femoral neck fractures not diagnosed on thin-cut high-resolution CT in 12% of patients with femoral shaft fractures [54]. A multicenter cohort study identifies a subgroup of elderly patients with MRI-verified Garden I and II femoral neck fractures sustained after trauma as occult fractures [52]. Femoral neck stress fractures are an infrequent condition in athletic and military populations where a high index of suspicion with liberal use of MRI is vital for early recognition [82]. Early diagnosis of spontaneous bilateral femoral neck fractures associated with low serum vitamin D levels could have avoided further displacement of the fracture and surgical treatment [15].

CT: Computerized tomography is helpful in identifying the fracture pattern in concurrent ipsilateral Tillaux and medial malleolar fractures in adolescents [56].

Other Considerations: The Pipkin Classification of femoral head fractures is prognostically useful, with patients having Types 1 and 2 fractures generally experiencing better outcomes than those with Types 3 and 4 fractures [2]. Current evidence on femoral head fractures covers indications, variant patterns, surgical approaches, and outcomes [9]. The treatment aim for femoral head fractures should always be the anatomical reduction of the fragments [81]. Surgical intervention may not be required in all cases of atypical tensile-sided femoral neck stress fractures if the fracture location and severity allow for individualized treatment [1]. Intraoperative mechanical injury of the femoral neck or malpositioning of the femoral component may lead to changes in loading patterns resulting in acute and chronic biomechanical femoral neck fractures after hip resurfacing arthroplasty [3]. Computer-assisted percutaneous internal fixation allowed for internal fixation and osseous healing with minimum exposure to radiation and resolution of symptoms in a transverse acetabular nonunion [84].

Treatment

Non-Operative

Low-risk stress fractures generally respond to activity modification [7]. Nonoperative treatment of isolated greater trochanteric fractures using a fracture table with the direct anterior approach was uniformly successful [77]. Most pediatric pelvic fractures are treated nonsurgically with good results [71]. Effective management of pediatric trauma involves careful casting, timely intervention for open fractures, and recognition of complications such as compartment syndrome and nonaccidental trauma [20]. Early fracture fixation is often beneficial in children to avoid complications associated with prolonged immobilization, though management must be tailored to the patient's age and injury severity [24].

Operative

Indications: Surgical intervention may not be required in all cases of atypical tensile-sided femoral neck stress fractures if the fracture location and severity allow for individualized treatment [1]. High-risk stress fractures have a propensity to develop into chronic injuries and require more aggressive treatment [7]. For patients with acetabular fracture and concomitant ipsilateral intertrochanteric femur fracture who undergo surgical treatment, fracture healing is usually achieved, but complications such as avascular necrosis are the major cause of a poor prognosis [41]. The optimal treatment of fractures with vascular injuries includes providing skeletal stability and confirming or reestablishing adequate distal perfusion as soon as possible, requiring a coordinated multidisciplinary approach [46]. Nonagenarians presenting with a hip fracture who would have been considered for total hip replacement (THR) on an elective basis should not be precluded from an emergency THR on safety grounds [62].

Surgical Approach / Technique: Early definitive management of femoral shaft fractures (less than 24 hours) is considered safe and beneficial for most patients, including those with head or thoracic trauma, when appropriate monitoring and resuscitation are utilized [64]. Short and long-term outcomes of traumatic hip dislocation are largely driven by the amount of time from injury to reduction and associated injuries [5]. Multiple management options have been proposed for acetabular fractures in the elderly, but no intervention has become the standard of care [14].

Implant Selection: Internal fixation of intracapsular fractures of the hip using a dynamic locking plate may represent an advance in the treatment of this difficult and common fracture [10]. The rate of fracture healing after dynamic locking blade plate (DLBP) fixation of displaced femoral neck fractures in young patients is promising [38]. Dynamic compression system (DCS) and multiple cancellous screws (MCS) demonstrated effectiveness in treating femoral neck fractures in young adults [40]. 3D-printed modular hemipelvic endoprosthetic reconstruction following periacetabular tumor resection demonstrates stable fixation with acceptable early functional and radiographic outcomes [28].

Other Considerations: Patients with healed intracapsular femoral neck fractures without complications function well more than sixty months after the fracture [8]. Overall complication risk after hip fracture fixation in nonagenarians remains relatively low but is higher than in younger counterparts [72]. Interventions to prevent subsequent fracture were instituted in only 1 of 4 patients with femoral neck fracture in the elderly, even though a focused directive was included in both study protocols [13]. The current assessment of outcomes in surgery for acetabular fractures lacks scientific rigour and does not give reliable outcome data for either scientific comparison or patient counselling due to the use of non-validated functional outcome measures [73].

Complications

Periprosthetic fracture: Periprosthetic femoral fractures occur at different rates at different times depending on the method of fixation [6]. Intraoperative mechanical injury of the femoral neck or malpositioning of the femoral component may lead to changes in loading patterns resulting in acute and chronic biomechanical femoral neck fractures after hip resurfacing arthroplasty [3]. There was no significant difference in long-term mortality or reoperation rates between patients undergoing early (< 48 hours) or late (> 48 hours) surgery for periprosthetic proximal femoral fractures [26].

Femoral neck fracture complications: Displaced and unstable fresh femoral neck fractures in adults are attributed to a higher incidence of complications with internal fixation using fully threaded cannulated compression screws [11]. A longer duration between surgical fixation and the first adverse event before stabilization of the fracture site may be a risk factor for revision surgery in older female patients with low bone mass undergoing fixation of Pauwels classification type II femoral neck fractures [19]. Patients with healed femoral neck fractures without complications were found to be functioning well more than sixty months after the fracture [8]. Low-risk stress fractures generally respond to activity modification, while high-risk fractures have a propensity to develop into chronic injuries and require more aggressive treatment [7]. Surgical intervention may not be required in all cases of atypical tensile-sided femoral neck stress fractures if the fracture location and severity allow for individualized treatment [1].

Hip fracture outcomes: A hip fracture has a long-term impact on health-related quality of life (HRQOL) and is a strong predictor of worsened physical health [16]. Although mortality is high, surviving hip fracture patients experience measurable gains in function and well-being in the 3 years after the fracture [18]. By the end of the 10-year follow-up, 1 in 4 deaths in the hip fracture group was attributable to the hip fracture [25]. The risk of mortality within the first 6 months of observation was significantly and independently associated with low trauma hip fracture [29]. Other fracture-recovery outcomes were similar between teriparatide and risedronate groups after pertrochanteric hip fracture [4].

Traumatic dislocation: Short and long-term outcomes of traumatic hip dislocation are largely driven by the amount of time from injury to reduction and associated injuries [5].

Other Considerations: Interventions to prevent subsequent fracture were instituted in only 1 of 4 elderly patients with femoral neck fractures, despite focused directives in study protocols [13]. No intervention has become the standard of care for acetabular fractures in the elderly [14]. Outcomes data exist for isolated acetabulum and pelvic ring injuries, but no such data currently exist for combined injuries [21]. The epidemiology of femoral shaft fractures in children living in the United States is different than that described in earlier, Scandinavian reports [27].

Recovery

Light activity (weeks): Evidence does not specify a discrete week range for light activity or driving. However, functional recovery assessments in the elderly include the ability to return to preinjury independence and walking ability [37]. For cognitively intact elderly patients who were ambulatory and living at home prior to injury, an operative delay of more than two calendar days after admission is an important predictor of mortality within one year [85].

Full activity (months): No specific month range for full activity return is defined in the evidence base. Surviving patients with hip fracture experience measurable gains in function and well-being in the 3 years after the fracture, despite high mortality [18]. Functional recovery after hip fracture in the elderly involves evaluation of one-year mortality, need for nursing home care, and ability to return to preinjury independence, walking ability, and activities of daily living [37].

Complete recovery / outcome plateau (months): Hip fracture leads to a persistent reduction in measured health-related quality of life (HRQoL) up to 36 months [43]. Hip fracture has a long-term impact on health-related quality of life (HRQOL) and is a strong predictor of worsened physical health [16]. By the end of the 10-year follow-up, 1 in 4 deaths in the hip fracture group was attributable to the hip fracture [25]. Patients with healed femoral neck fractures without complications function well more than sixty months after the fracture [8].

Rehabilitation protocol: The evidence does not specify PT phasing, immobilisation duration, or weight-bearing progression. Interventions to prevent subsequent fracture were instituted in only 1 of 4 patients with femoral neck fracture in the elderly, despite focused directives in study protocols [13]. No single intervention has become the standard of care for acetabular fractures in the elderly [14].

Functional milestones: Other fracture-recovery outcomes were similar when comparing Teriparatide to Risedronate after pertrochanteric hip fracture [4]. Short and long-term outcomes for traumatic hip dislocation are largely driven by the time from injury to reduction and associated injuries [5]. Fractures in periprosthetic femoral fractures occur at different rates at different times depending on the method of fixation [6]. There was no significant difference in long-term mortality or reoperation rates between patients undergoing early (< 48 hours) or late (> 48 hours) surgery for periprosthetic proximal femoral (PPF) fractures [26]. A longer duration between surgical fixation and the first adverse event before stabilization of the fracture site may be a risk factor for revision surgery in femoral neck fractures [19]. The risk of mortality within the first 6 months of observation was significantly and independently associated with low trauma hip fracture [29]. The long-term survival of the native hip joint after operatively treated displaced acetabular fractures was good, but injury to the femoral head and acetabular impaction were strong predictors of failure, especially in patients aged > 60 years [42]. The high rate of late-stage osteonecrosis reflects the tertiary care nature of the clinic, and disease stage at presentation is the main determinant for treatment selection regardless of symptom duration [86].

Key Evidence

  • [L4] Surgical intervention may not be required in all cases if the fracture location and severity allow for individualized treatment. (10.1177/0363546503262195)
  • [L4] However, it is prognostically useful, as patients with Types 1 and 2 fractures generally have better outcomes than those with Types 3 and 4 fractures. (10.1007/s11999.0000000000000045)
  • [L4] Intraoperative mechanical injury of the femoral neck or malpositioning of the femoral component may lead to changes in loading patterns resulting in acute and chronic biomechanical femoral neck fractures. (10.2106/jbjs.h.01113)
  • [L2] Other fracture-recovery outcomes were similar. (10.2106/jbjs.15.01217)
  • [L5] Short and long-term outcomes are largely driven by the amount of time from injury to reduction and associated injuries. (10.5435/jaaos-d-23-01013)
  • [L3] The study identifies risk factors and fracture patterns, noting that fractures occur at different rates at different times depending on the method of fixation. (10.1302/0301-620x.98b4.37203)
  • [L5] Stress fractures are classified as low-risk or high-risk injuries; low-risk fractures generally respond to activity modification, while high-risk fractures have a propensity to develop into chronic injuries and require more aggressive treatment. (10.5435/00124635-200011000-00002)
  • [L4] Patients with healed fractures without complications were found to be functioning well more than sixty months after the fracture. (10.2106/00004623-199412000-00005)
  • [L4] The purpose of this review was to summarize current evidence on femoral head fractures regarding indications, variant patterns, surgical approaches, and outcomes. (10.5435/jaaos-d-23-01121)
  • [L4] The authors conclude that this new fixation device might represent an advance in the treatment of this difficult and common fracture. (10.1302/0301-620x.95b10.31511)
  • [L3] Displaced fractures and unstable fractures were attributed to the higher incidence of complications. (10.1186/s13018-022-03005-8)
  • [L1] The guideline includes 16 recommendations and three option statements to assist orthopaedic surgeons and qualified physicians managing patients older than 55 years with hip fractures based on the best current available evidence. (10.5435/jaaos-d-22-00125)
  • [L2] Interventions to prevent a subsequent fracture were instituted in only 1 of 4 patients, even though a focused directive was included in both study protocols. (10.2106/jbjs.22.00088)
  • [L5] Multiple management options have been proposed, but no intervention has become the standard of care for acetabular fractures in the elderly. (10.5435/jaaos-d-15-00510)
  • [L4] Early diagnosis could have been helpful to avoid further displacement of the fracture and surgical treatment. (10.1016/j.arth.2008.01.309)
  • [L3] A hip fracture has a long-term impact on HRQOL and is a strong predictor of worsened physical health. (10.1186/1471-2474-11-226)
  • [L2] Although mortality is high, surviving patients experience measurable gains in function and well-being in the 3 years after the fracture. (10.5435/jaaos-d-19-00530)
  • [L3] A longer duration between surgical fixation and the first adverse event before stabilization of the fracture site may be a risk factor for revision surgery. (10.1186/s12891-024-07179-6)
  • [L4] Although outcomes data exist for isolated injuries, no such data currently exist for combined injuries. (10.5435/jaaos-22-05-304)
  • [L4] A novel classification system using CT scanning guides treatment for femoral head fracture-dislocations, with outcomes showing osteoarthritis in 43.7% of cases but well-tolerated symptoms in 94% of patients. (10.1016/j.otsr.2012.11.007)
  • [L4] Orthopaedic surgeons in Norway failed to report correct data on pathologic fractures and the corresponding cancer diagnosis in an acute setting in many patients. (10.1186/s13018-023-04336-w)
  • [L2] By the end of the 10-year follow-up, 1 in 4 deaths in the hip fracture group was attributable to the hip fracture. (10.1186/s12891-017-1606-1)
  • [L3] This study found no significant difference in long-term mortality or reoperation rates between patients undergoing early (< 48 hours) or late (> 48 hours) surgery for PPF fractures. (10.1016/j.arth.2025.07.009)
  • [L3] For children living in the United States today, the epidemiology of these fractures is different than that described in earlier, Scandinavian reports. (10.2106/00004623-199904000-00007)
  • [L4] These preliminary results demonstrate stable fixation with acceptable early functional and radiographic outcomes. (10.2106/jbjs.19.01437)
  • [L2] The risk of mortality within the first 6 months of observation was significantly and independently associated with low trauma hip fracture. (10.1186/1471-2474-13-143)
  • [L4] All injury patterns can likely be identified using the proposed classification system. (10.1186/s12891-021-04703-w)
  • [L1] This clinical practice guideline provides recommendations for the diagnosis and treatment of hip fractures in the elderly based on a systematic review of current scientific and clinical information. (10.2106/jbjs.o.00229)
  • [L4] Our findings differed from European data and suggest a delicate balance in hip geometry in Arctic populations. (10.1186/s13018-021-02482-7)
  • [L4] The Unified Classification System (UCS) is unsatisfactory for the classification of periprosthetic femoral fractures around polished taper-slip stems, demonstrating considerably lower reliability and validity than previously described for other stem types. (10.1302/0301-620x.103b8.bjj-2021-0021.r1)
  • [L5] The treatment algorithm for diagnosing and treating osteoporosis in in-patient trauma surgery patients can help identify high-risk patients systematically and efficiently. (10.1186/s13018-017-0585-0)
  • [L3] Fractures with a preoperative classification of AO type 31 A3 can be expected to have worse results than A2 ITF fractures. (10.1186/s13018-018-0911-1)
  • [L5] The goal of this special focus issue is to help keep physicians that care for athletes up to date regarding the latest developments pertaining to new technology to hasten diagnosis and preferred management of blunt trauma injuries. (10.1016/j.csm.2013.01.002)
  • [L4] The purpose of this review is to evaluate the functional outcome of fractures of the hip in the elderly, with specific emphasis on one-year mortality; the need for short and long-term care in a nursing home; and the ability to return to the preinjury level with regard to independence, the ability to walk, and the ability to perform activities of daily living. (10.2106/00004623-199405000-00018)
  • [L4] The rate of fracture healing after DLBP fixation of displaced femoral neck fracture in young patients is promising and warrants further investigation by a randomized trial to compare the performance against other contemporary methods of fixation. (10.1302/0301-620x.100b4.bjj-2016-1098.r3)
  • [L4] Among the three-column classification, quadrilateral plate fractures are commonly observed in type B and C. (10.1186/s13018-024-04783-z)
  • [L3] DCS and MCS demonstrated effectiveness in treating femoral neck fractures in young adults. (10.1186/s13018-024-04913-7)
  • [L4] For patients who have undergone surgical treatment, fracture healing is usually achieved, but complications, especially avascular necrosis, are the major cause of a poor prognosis. (10.1186/s13018-020-02139-x)
  • [L3] The long-term survival of the native hip joint after acetabular fractures was good, but the presence of injury to the femoral head and acetabular impaction proved to be strong predictors of failure, especially in patients aged > 60 years. (10.1302/0301-620x.99b6.bjj-2016-1013.r1)
  • [L3] Hip fracture leads to a persistent reduction in measured HRQoL, up to 36 months. (10.1302/0301-620x.106b4.bjj-2023-0904.r1)
  • [L4] The original Judet and Letournel classification system is difficult to apply to the modern spectrum of acetabular fractures, particularly in older patients with low-energy injuries. (10.1302/0301-620x.97b8.33653)
  • [L5] The optimal treatment of fractures with vascular injuries includes providing skeletal stability and confirming or reestablishing adequate distal perfusion as soon as possible, requiring a coordinated multidisciplinary approach. (10.5435/jaaos-d-21-00660)
  • [L5] Recent data demonstrate better outcomes with internal fixation methods in most open tibial fractures, but external fixation continues to be an appropriate choice in more severe injuries. (10.1302/2058-5241.3.170072)
  • [L5] The correct approach depends on the Vancouver classification, with B1 fractures treated by fixation, B2 by revision with a long stem, and B3 by complex reconstruction or prosthetic replacement. (10.1302/0301-620x.96b11.34300)
  • [L3] The treatment of femoral neck fractures with FNS is superior and contributes to improved hip joint function, with biomechanical research confirming its structural stability and advantages in resisting femoral head varus. (10.1186/s12891-024-07863-7)
  • [L4] Salvage of failed internal fixations of IT fractures with properly selected implants and profound techniques can lead to the formulation of valuable surgical strategies and provide patients with satisfactory clinical outcomes. (10.1186/s12891-020-03593-8)
  • [L5] This multicenter cohort study identifies a subgroup of elderly patients with MRI verified Garden I and II FNFs sustained after trauma, i.e. occult fractures. (10.1186/s12891-022-05088-0)
  • [L4] The authors recommend the liberal use of magnetic resonance imaging to detect injuries not discoverable by history and physical examination alone. (10.2106/jbjs.d.02306)
  • [L3] Rapid limited-sequence MRI of the pelvis for patients with femoral shaft fractures identified femoral neck fractures that were not diagnosed on thin-cut high-resolution CT in 12% of our patients. (10.2106/jbjs.19.00568)
  • [L3] FNS has excellent biomechanical properties and shows significantly higher overall construct stability. (10.1186/s13018-021-02517-z)
  • [L4] Computerized tomography is helpful in identifying the fracture pattern. (10.1186/s13018-020-01961-7)
  • [L5] From the perspective of biomechanics, when the Pauwels angle was 30°, positive buttress was more stable to negative buttress. (10.1186/s12891-022-06124-9)
  • [Paper] The biomechanical performance of the FNS is fracture-type-dependent, necessitating angle-specific optimisation. (10.1186/s12891-026-09591-6)
  • [L3] Based on successful long-term results, the authors prefer the rendezvous technique with fracture stabilization from distally to proximally, advising initial damage control orthopedics followed by staged definitive fixation. (10.1186/s13018-014-0149-5)
  • [L3] Pathologic hip fractures result in significantly higher complication rates than native hip fractures after surgical treatment, suggesting that guidelines for native hip fractures may not be generalizable for pathologic hip fractures. (10.1016/j.arth.2020.01.003)
  • [L3] Therefore, nonagenarians presenting with a hip fracture who would have been considered for a THR if presenting on an elective basis should not be precluded from an emergency THR on safety grounds. (10.1186/s12891-024-07340-1)
  • [L4] The present study highlights the morphological diversity and complexity within femoral neck fractures in young and middle-aged adults, which allows for more accurate simulation of femoral neck fracture patterns in future biomechanical studies. (10.1186/s12891-024-07207-5)
  • [L4] Congenital subluxation and dislocation of the hip are distinct clinical entities with a common etiology of genetic or biomechanical dysplasia; early treatment during infancy before weight-bearing is critical to enhance growth potential and prevent secondary pathological changes. (10.2106/00004623-194931020-00012)
  • [L3] Impingement-type sports are most frequently associated with hip injuries. (10.1016/j.arthro.2019.03.044)
  • [L4] Our observations demonstrated that, even in a population who suffered a fragility hip fracture, men still have higher trabecular bone mechanical properties in comparison with women. (10.1186/1471-2474-14-295)
  • [L3] Overall complication risk after hip fracture fixation in nonagenarians remains relatively low but higher than their younger counterparts. (10.1016/j.arth.2020.06.005)
  • [L2] The current assessment of outcomes in surgery for acetabular fractures lacks scientific rigour and does not give reliable outcome data for either scientific comparison or patient counselling due to the use of non-validated functional outcome measures. (10.1302/0301-620x.98b5.36292)
  • [L3] The morphology of the proximal femur and the pelvis do not differ in several radiological parameters in patients sustaining a PFF between cementless short stem and straight stem THA. (10.1186/s13018-025-05502-y)
  • [L3] Nonoperative treatment was uniformly successful. (10.1016/j.arth.2018.02.051)
  • [L3] Stability of the hip after PFA is influenced by variables associated with the patient, the pathology, the surgical technique and the implant. (10.1302/0301-620x.99b4.bjj-2016-0960.r1)
  • [L5] Hip surveillance programmes aim to identify and address hip pathology proactively through serial radiological and clinical assessments, helping to standardize care, reduce the incidence of hip dislocation, and prevent the need for salvage procedures. (10.1302/0301-620x.107b7.bjj-2025-0167.r1)
  • [L4] The treatment aim should always be the anatomical reduction of the fragments. (10.1186/s12891-023-06317-w)
  • [L5] Femoral neck stress fractures are an infrequent condition in athletic and military populations where a high index of suspicion with liberal use of MRI is vital for early recognition. (10.2106/jbjs.21.00896)
  • [L5] The authors recommend careful evaluation of preoperative radiographs, use of high-quality biplanar imaging during the procedure, and postoperative full-length radiographs to rule out intra-articular penetration by bone fragments. (10.2106/00004623-199607000-00015)
  • [L4] The technique allowed for internal fixation and osseous healing with minimum exposure to radiation and resolution of symptoms. (10.2106/00004623-200002000-00008)
  • [L2] An operative delay of more than two calendar days after admission is an important predictor of mortality within one year for elderly patients who have a fracture of the hip and who are cognitively intact, able to walk, and living at home before the fracture. (10.2106/00004623-199510000-00010)
  • [L5] The authors clarify that the high rate of late-stage osteonecrosis reflects the tertiary care nature of their clinic and that the stage of disease at presentation is the main determinant for treatment selection, regardless of the duration of symptoms prior to presentation. (10.1016/j.arth.2020.09.037)

References

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[16] Two-year changes in quality of life in elderly patients with low-energy hip fractures. A case-control study. BMC Musculoskeletal Disorders. 2010. DOI: 10.1186/1471-2474-11-226

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[24] Chapter 38 High-Energy Injury and Polytrauma. 2020.

[25] The impact of hip fracture on mortality in Estonia: a retrospective population-based cohort study. BMC Musculoskeletal Disorders. 2017. DOI: 10.1186/s12891-017-1606-1

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[32] Hip geometry in hip fracture patients in Greenland occurring over a 7.7-year period. Journal of Orthopaedic Surgery and Research. 2021. DOI: 10.1186/s13018-021-02482-7

[33] Reliability and validity of the Unified Classification System for postoperative periprosthetic femoral fractures around cemented polished taper-slip stems. The Bone & Joint Journal. 2021. DOI: 10.1302/0301-620x.103b8.bjj-2021-0021.r1

[34] Investigation and management of osteoporosis in aged trauma patients: a treatment algorithm adapted to the German guidelines for osteoporosis. Journal of Orthopaedic Surgery and Research. 2017. DOI: 10.1186/s13018-017-0585-0

[35] The relationship between the type of unstable intertrochanteric femur fracture and mobility in the elderly. Journal of Orthopaedic Surgery and Research. 2018. DOI: 10.1186/s13018-018-0911-1

[36] Blunt Trauma Injuries. Clinics in Sports Medicine. 2013. DOI: 10.1016/j.csm.2013.01.002

[37] Functional recovery after fracture of the hip.. The Journal of Bone & Joint Surgery. 1994. DOI: 10.2106/00004623-199405000-00018

[38] Displaced femoral neck fractures in patients 60 years of age or younger: results of internal fixation with the dynamic locking blade plate. The Bone & Joint Journal. 2018. DOI: 10.1302/0301-620x.100b4.bjj-2016-1098.r3

[39] Quadrilateral plate classification program of acetabular fractures based on three-column classification: a three-dimensional fracture mapping study. Journal of Orthopaedic Surgery and Research. 2024. DOI: 10.1186/s13018-024-04783-z

[40] Comparison of dynamic compression system versus multiple cancellous screws in the treatment of femoral neck fractures in young adults. Journal of Orthopaedic Surgery and Research. 2024. DOI: 10.1186/s13018-024-04913-7

[41] As an unusual traumatic presentation, acetabular fracture and concomitant ipsilateral intertrochanteric femur fracture: a retrospective case series of 18 patients. Journal of Orthopaedic Surgery and Research. 2020. DOI: 10.1186/s13018-020-02139-x

[42] Long-term survival and risk factors for failure of the native hip joint after operatively treated displaced acetabular fractures. The Bone & Joint Journal. 2017. DOI: 10.1302/0301-620x.99b6.bjj-2016-1013.r1

[43] Patient-reported outcome measures in hip fracture patients. The Bone & Joint Journal. 2024. DOI: 10.1302/0301-620x.106b4.bjj-2023-0904.r1

[44] The ongoing relevance of acetabular fracture classification. The Bone & Joint Journal. 2015. DOI: 10.1302/0301-620x.97b8.33653

[46] Assessment and Interventions for Vascular Injuries Associated With Fractures. Journal of the American Academy of Orthopaedic Surgeons. 2022. DOI: 10.5435/jaaos-d-21-00660

[47] Open fractures of the lower extremity. EFORT Open Reviews. 2018. DOI: 10.1302/2058-5241.3.170072

[48] Periprosthetic fractures. The Bone & Joint Journal. 2014. DOI: 10.1302/0301-620x.96b11.34300

[49] Comparative analysis of the femoral neck system (FNS) vs. cannulated cancellous screws (CCS) in the treatment of Middle-aged and elderly patients with femoral neck fractures: clinical outcomes and biomechanical insights. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-07863-7

[50] Chapter 12 Hip Microinstability. 2019.

[51] Revision surgery due to failed internal fixation of intertrochanteric femoral fracture: current state-of-the-art. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-020-03593-8

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[54] Improving the Diagnosis of Ipsilateral Femoral Neck and Shaft Fractures. Journal of Bone and Joint Surgery. 2019. DOI: 10.2106/jbjs.19.00568

[55] Clinical outcome of femoral neck system versus cannulated compression screws for fixation of femoral neck fracture in younger patients. Journal of Orthopaedic Surgery and Research. 2021. DOI: 10.1186/s13018-021-02517-z

[56] Concurrent ipsilateral Tillaux fracture and medial malleolar fracture in adolescents: management and outcome. Journal of Orthopaedic Surgery and Research. 2020. DOI: 10.1186/s13018-020-01961-7

[57] Biomechanical study of femoral neck system for young patients with nonanatomically reduced femoral neck fractures: a finite element. BMC Musculoskeletal Disorders. 2023. DOI: 10.1186/s12891-022-06124-9

[58] Finite element analysis of the influence of femoral neck system implantation angle on biomechanical stability in femoral neck fractures: a mechanistic exploration. BMC Musculoskeletal Disorders. 2026. DOI: 10.1186/s12891-026-09591-6

[60] Surgical treatment of ipsilateral multi-level femoral fractures. Journal of Orthopaedic Surgery and Research. 2015. DOI: 10.1186/s13018-014-0149-5

[61] Pathologic Versus Native Hip Fractures: Comparing 30-day Mortality and Short-term Complication Profiles. The Journal of Arthroplasty. 2020. DOI: 10.1016/j.arth.2020.01.003

[62] Comparison of acute outcomes from elective total hip replacements and after fragility femoral neck fractures in nonagenarians. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-07340-1

[63] Morphological characteristics of femoral neck fractures in young and middle-aged population: a retrospective descriptive study. BMC Musculoskeletal Disorders. 2024. DOI: 10.1186/s12891-024-07207-5

[64] Chapter 37 Femoral Shaft Fractures. 2021.

[65] CONGENITAL DYSPLASIA OF THE HIP JOINT. The Journal of Bone & Joint Surgery. 1949. DOI: 10.2106/00004623-194931020-00012

[67] A Sport‐specific Analysis of the Epidemiology of Hip Injuries in National Collegiate Athletic Association Athletes From 2009 to 2014. Arthroscopy. 2019. DOI: 10.1016/j.arthro.2019.03.044

[68] At the moment of occurrence of a fragility hip fracture, men have higher mechanical properties values in comparison with women. BMC Musculoskeletal Disorders. 2013. DOI: 10.1186/1471-2474-14-295

[69] Surgical Dislocation of the Hip (Ganz Surgical Dislocation of Hip, Open Dislocation of Hip). 2016.

[71] Chapter 139 Pediatric Pelvic and Lower Extremity Fractures. 2019.

[72] Operative Fixation of Hip Fractures in Nonagenarians: Is It Safe?. The Journal of Arthroplasty. 2020. DOI: 10.1016/j.arth.2020.06.005

[73] Assessment of functional outcomes of surgically managed acetabular fractures. The Bone & Joint Journal. 2016. DOI: 10.1302/0301-620x.98b5.36292

[75] Chapter 20 Pelvic Trauma. 2020.

[76] Periprosthetic femoral fractures in minimally-invasive anterolateral short stem versus transgluteal straight stem cementless total hip arthroplasty: What are the differences in the femoral and pelvic morphology?. Journal of Orthopaedic Surgery and Research. 2025. DOI: 10.1186/s13018-025-05502-y

[77] Isolated Greater Trochanteric Fracture and the Direct Anterior Approach Using a Fracture Table. The Journal of Arthroplasty. 2018. DOI: 10.1016/j.arth.2018.02.051

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[82] Femoral Neck Stress Fractures in Athletes and the Military. Journal of Bone and Joint Surgery. 2021. DOI: 10.2106/jbjs.21.00896

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