Trauma remains a leading cause of morbidity and mortality worldwide. Lower extremity trauma can result in devastating consequences regarding patients’ physical function, mental health, economic welfare, and ability to function independently. Long-term sequelae, such as posttraumatic osteoarthritis due to articular injuries, nonunion/malunion, limb-length discrepancy, or limb deformity, occur if proper treatment principles of fracture reduction and stabilization are not followed. Nonetheless, even with proper nonsurgical or surgical management, complications can still arise. Open fractures are quite common in lower extremity trauma with expected worse outcomes and increased complications. It is important to review the most recent evidence-based treatment recommendations regarding different anatomic locations of injury.

Femoral head fractures are rare injuries most often associated with 11% of high-energy hip dislocations.¹ Often these fractures require fixation to restore hip stability, whether or not an associated posterior wall fracture is present. Surgical fixation consists of headless screws or countersunk screws to prevent articular incongruity. The two surgical approaches are the Smith-Petersen/modified Heuter approach and surgical hip dislocation. In a 2020 study comparing the two approaches in patients with Pipkin I and II femoral head fractures treated with open reduction and internal fixation (ORIF), surgical time, blood loss, and pain scores were lower in the modified Heuter group; however, there were no differences in day-of-discharge pain scores, length of hospital stay, union, osteonecrosis, or functional outcomes as measured by modified Merle d’Aubigné and Oxford hip scores.²

A 2020 study investigated the long-term outcomes of femoral head fractures.¹ Twenty-eight femoral head fractures with at least 10-year follow-up were examined. All patients were treated with one or a combination of the following: nonsurgical management, ORIF, fragment excision, or total hip arthroplasty (THA), and functional outcomes were measured by the Oxford hip score. The average follow-up was 14 years, and patients’ average age at the time of injury was 39.2 years with 86% of patients having surgery. Overall, seven patients had late conversion to THA, with three of those patients requiring a later THA revision. The average Oxford hip scores in all 28 patients was 37 in the native femoral head retained group, 41 in the primary THA group, and 31.4 in the group requiring a secondary THA.¹ Overall, the study shows that ORIF of the femoral head may have satisfactory long-term outcomes, but currently outcomes remain unpredictable.

Femoral neck fractures are typically categorized as either low-energy fractures in geriatric patients with poor bone quality or high-energy fractures in young patients. This differentiation is important for displaced fractures
because it affects treatment algorithms: younger patients undergo surgical reduction and fixation, whereas geriatric patients are treated with arthroplasty. Definitive treatment options are based on physiologic age, bone density, and fracture pattern.

In physiologically young patients with displaced femoral neck fractures, the goal of care remains anatomic reduction and stable fixation to achieve union and preserve hip biomechanics. Although open reduction is considered the gold standard, recent literature has reexamined whether this is always necessary. A 2020 multicenter retrospective study evaluated the factors associated with performing an open reduction and the association of revision surgery with open versus closed reduction.³ Open reduction was associated with study center, younger age, transcervical fracture location, posterior fracture comminution, no history of osteoporosis, and surgery within 12 hours.³ For open reduction, 71% had acceptable reduction and 33% underwent revision surgery compared with 69% acceptable reduction and a 28% revision surgery rate in fractures treated with closed reduction, with the revision surgery rate being statistically significant, representing a 2.4-fold greater propensity-adjusted hazard of revision surgery.³ However, the study could neither determine causality nor eliminate injury severity as potential bias.

Fixation constructs for femoral neck fractures continue to evolve. Historically, these fractures have been stabilized with cannulated screws or sliding hip screws. Newer technology and techniques, including fibular strut grafts and novel fixed-angle locking plates with controlled dynamic compression, aim to increase stability of fracture fixation⁴ (Figure 1).

As the geriatric population continues to grow, so does the incidence of geriatric hip fractures and multicenter randomized controlled trial (RCT) investigation outcomes. The HIP fracture Accelerated surgical TreaTment And Care tracK (HIP ATTACK) international RCT examined whether patients with earlier surgical treatment had better outcomes than patients who received standard of care. Patients older than 45 years with a hip fracture were randomized to receive accelerated surgical care (within 6 hours of diagnosis) or standard of care (within 48 hours). There were 2,970 patients randomized: 1,487 to the accelerated surgical procedure group and 1,483 to standard treatment group.⁵ The median time from hip fracture diagnosis to the surgical procedure was 6 hours in the accelerated surgical procedure group and 24 hours in the standardcare group.⁵ Mortality and major complications were similar between the groups. The study showed that with standard care, an accelerated surgical procedure did not lower the risk of mortality or major complications.

A subset analysis of the Fixation using Alternative Implants for the Treatment of Hip fractures (FAITH) study, an RCT comparing cannulated screws with sliding hip screws, assessed posterior tilt and need for arthroplasty in patients with Garden I and II femoral neck fractures. Patients with posterior tilt greater than 20° on preoperative imaging had a 2.2-fold increased risk of subsequent arthroplasty after initial fixation.⁶ In addition, patients older than 80 years were also at increased risk. Given these results, primary arthroplasty instead of internal fixation may be warranted in older patients with femoral neck fractures, especially those presenting with greater than 20° of posterior tilt.

For patients undergoing arthroplasty, typically THA has been favored over hemiarthroplasty for active, high-functioning geriatric patients. The Hip Fracture Evaluation with Alternatives of Total Hip Arthroplasty versus Hemi-Arthroplasty (HEALTH) study is an international, multicenter RCT that compared THA with hemiarthroplasty.⁷ A total of 1,495 patients with hip fracture who were age 50 years or older were randomized to THA or hemiarthroplasty and followed for 24 months. Differences were noted in terms of the primary outcome of secondary surgical procedure nor mortality. Patients who received a THA had a twofold increased risk of dislocation compared with those who had hemiarthroplasty in addition to slightly increased risk of serious adverse events. Functional outcomes using the Western Ontario and McMaster Universities Osteoarthritis Index were slightly better with THA compared with hemiarthroplasty but did not meet clinically important difference, and there were no differences in
the Timed Up and Go tests. A similar RCT of 120 octogenarians with displaced femoral neck fractures found no difference between the THA and hemiarthroplasty groups regarding hip function, quality of life, complications, or pain.⁸ Although the potential advantages of THA for hip fractures may not be as strong as previously thought, data beyond 2 years remain limited.

For patients being treated with hemiarthroplasty, recent studies have evaluated optimal surgical techniques. A meta-analysis of 21 studies with 61,487 patients with hip fractures treated with hemiarthroplasty compared surgical approaches (anterior, lateral, posterior).⁹ The posterior approach was associated with the greatest risk of dislocation compared with lateral or anterior approaches. In addition, the posterior approach was also associated with increased risk of revision surgery compared with the other approaches. An RCT of 400 patients with hip fractures treated with hemiarthroplasty compared cemented with cementless techniques at 1-year follow-up.¹⁰ Mortality was higher in the cementless group, and mobility improved in the cemented group. Revision surgery rates were similar. In agreement with the American Academy of Orthopaedic Surgeons Clinical Practice Guideline on Management of Hip Fractures in the Elderly, cemented femoral stems for patients with femoral neck fractures are recommended.

Femoral neck fractures remain common in the geriatric population and can also be seen in young patients with high-energy trauma. In physiologically young patients, ORIF remains the standard of care to optimize reduction and outcomes. For geriatric patients, arthroplasty may be a more reliable treatment method than fixation, although this remains dependent on patient factors, fracture morphology, and implant construct.

The primary treatment of intertrochanteric femoral fractures is reduction and fixation regardless of age. Understanding these fracture patterns have taken on increased importance in understanding reduction and fixation strategies. A study compared CT with plain radiographs in evaluating intertrochanteric femoral fracture patterns.¹¹ The study found poor correlation between the two imaging modalities and that CT could better predict fixation failure because coronal patterns and lateral wall integrity were better assessed. Understanding the fracture pattern is important, as recent studies demonstrated that reduction is critical to successful union and to prevent femoral neck shortening, which has been associated with inferior clinical results.¹²,¹³

Fixation of intertrochanteric femoral fractures with short or long cephalomedullary nail constructs has long been debated. A meta-analysis examined the growing literature examining this question in AO 31-A1 and 31-A2 fractures.¹⁴ Six high-quality studies were included after screening 2,741 articles, and outcomes of interest were revision surgery rate, surgical time, length of hospital stay, 1-year mortality. No differences were found between the groups, except short nails had decreased surgical time compared with long nails. In addition, using the Danish Multidisciplinary Hip Fracture Registry, 2,245 pertrochanteric fractures were identified; 1,867 were treated with a short intramedullary nail, and 378 were treated with a long intramedullary nail.¹⁵ This study confirmed that for subtrochanteric fractures, a long intramedullary nail has a lower rate of major revision surgeries compared with a short intramedullary nail. In contrast, a short intramedullary nail has a lower rate of major revision surgeries compared with a long intramedullary nail for pertrochanteric fractures.

The theoretical concerns regarding short nails (periprosthetic fractures, instability, implant failures) have not borne out in the literature. Short nails may be broadly applied to intertrochanteric femoral fractures except for those fracture patterns with subtrochanteric extension.

Subtrochanteric femoral fractures are now routinely treated with intramedullary fixation, but issues with mechanical alignment and nonunion are continual challenges. A study investigated the nonunion risk factors associated in subtrochanteric femoral fractures treated with intramedullary fixation.¹⁶ A retrospective review of 74 patients with subtrochanteric femoral fractures treated with intramedullary fixation over a 6-year period found a nonunion rate of 23% (17 of 74). The risk factors associated with nonunion were postoperative varus malalignment, postoperative lack of medial cortical support, and autodynamization of the nail within the first 12 weeks after surgery. Accuracy of each of these three parameters to predict nonunion was greater than 0.70. Furthermore, the nonunion rate significantly increased with the number of risk factors (no risk factor: 2.9%, one risk factor: 23.8%, two risk factors: 52.9%, and three risk factors: 100%). This was further strengthened by a similar study looking at risk factors for nonunion/delayed healing in subtrochanteric femoral fractures.¹⁷ Sixty-one patients with subtrochanteric femoral fractures were retrospectively analyzed. Quality of the reduction, caput-collum-diaphyseal
angle, tip-apex distance, leg-length shortening, and fracture healing according to the Radiographic Union Score for Hip were assessed. Patients with better reductions and caput-collum-diaphyseal angles had higher rates of union. As these studies demonstrate, quality of reduction remains the most important factor in fracture healing.

The optimal treatment for adult femoral shaft fractures remains a reamed, statically locked intramedullary nail. With any high-energy shaft fracture, though, an ipsilateral femoral neck fracture must be ruled out. Historically this was done with thin-cut CT; however, subtle fractures can still be missed. A new study investigated the role of a modified, quick coronal MRI protocol.¹⁸ In a series of 39 high-energy shaft fractures that received both thin-cut CT and novel MRI protocol to evaluate for ipsilateral femoral neck fracture, four patients had a femoral neck fracture identified on MRI that was missed by CT (Figure 2). For geriatric low-energy femoral shaft fractures, intramedullary nails that have fixation into the femoral neck should be used. In a study from Sweden, patients older than 55 years with femoral shaft fractures had a higher rate of peri-implant fractures, especially hip fractures, in the group without femoral neck protection compared with the group with femoral neck protection.¹⁹ In the patient with polytrauma, early appropriate care, including early intramedullary fixation of femoral shaft fractures, is associated with improved outcomes systemically.²⁰

For native distal femoral fractures with intra-articular extension, ORIF remains the mainstay of treatment. The implants used for these fractures have been under evolution. A 2019 study examined fixation of these fractures with the traditional lateral locked plate in addition to a medial plate or intramedullary nailing.²¹ In this biomechanical study examining AO 33-C distal femoral fractures, the lateral plate-intramedullary nail and lateral plate-medial plate constructs had the strongest baseline stiffness, greatest survivability, and tolerated the most cycles to failure compared with lateral plating alone.

Distal femoral periprosthetic fractures above total knee arthroplasty implants have become increasingly frequent (Figure 3). A 2020 systematic review looked at fixation of these fractures comparing plating with intramedullary nailing.²² Plating had an overall decreased rate of complications or revision surgery. However, intramedullary nailing was associated with earlier weight bearing and more patients returning to preinjury level of function. For some fractures, distal femoral replacement (DFR) has been considered a treatment option. A meta-analysis compared the outcomes between DFR and ORIF for periprosthetic femoral fractures and found similar rates of complications but better motion in the ORIF group.²³ Internal fixation techniques, including retrograde intramedullary nailing and locked plating, are favored in most fractures when bone stock in the distal fragment allows for appropriate fixation and stability. In the setting of deficient distal femoral bone stock or femoral component loosening, revision arthroplasty with DFR is the favored technique.

Various fixation constructs exist for patellar fractures, each with their own unique advantages and disadvantages (Figure 4). A 2021 biomechanical study compared anterior plating with cannulated screw tension band technique in transverse patellar fractures.²⁴ The two constructs performed equally in ultimate load-to-failure strength and fatigue endurance under cyclical loading, although the tension band group had increased overall failures compared with the plating group. For inferior pole patellar fractures, often these have been treated with partial patellectomy and patellar tendon advancement. Although this generally restores the extensor mechanism, this procedure has been complicated by failure of bone-tendon healing, stiffness due to restrictive rehabilitation protocols, or patella baja. A 2021 study investigated managing these inferior pole fractures with suture anchors.²⁵ Of 21 patients treated with suture anchors, all patients had healing by 4 months and restoration of the knee extensor mechanism, and knee arc range of motion restored to an average of 135°. Overall, the goals of contemporary fixation strategies for the patella remain restoration of the functional integrity and strength of the extensor mechanism and articular congruity.

The three-column model for tibial plateau fractures has become more widely accepted and used. A study correlated this model with fracture mechanism: flexion varus, extension varus, hyperextension varus, flexion valgus, extension valgus, and hyperextension valgus.²⁶ The flexion varus type pattern was characterized by a primary fracture apex located posteromedially and was frequently associated with concomitant anterior

cruciate ligament avulsion (44.8%). The extension varus pattern had a characteristic medial fragment apex at the posteromedial crest or multiple apices symmetrically around the crest and was commonly completely articular in nature (65%). The hyperextension varus pattern is noted by anteromedial articular impaction, 51% with a fibular avulsion and 60% with posterior tension failure fragments. The flexion valgus pattern was characterized by articular depression posterolaterally, often (58.9%) with severe comminution of the posterolateral cortical rim. The extension valgus patterns only involved the lateral plateau, with central articular depression and/or a pure split. The hyperextension valgus pattern is denoted by anterolateral articular depression. A moderate positive association was found between flexion varus fractures and anterior cruciate ligament avulsions and between hyperextension varus fractures and fibular avulsions.

For tibial plateau fractures with articular depression, debate continues regarding the ideal graft to support the articular fragment once elevated. A multicenter RCT compared autologous iliac cortical bone graft with bioresorbable hydroxyapatite and calcium sulfate cement (Cerament bone void filler) in 135 patients with depressed tibial plateau fractures.²⁷ There were no significant differences in functional or pain scores at postoperative week 26. There was a significant reduction of blood loss and pain levels at postoperative day 1 in the Cerament bone void filler group. The rates of fracture healing, defect remodeling, and articular subsidence were not significantly different in both groups.

The role of soft-tissue injury and MRI in tibial plateau fractures remains unclear. However, a 2020 study that examined the outcomes of tibial plateau fractures with MRI identified soft-tissue injuries compared with those without a soft-tissue injury on MRI.²⁸ At 12 months postoperatively, there were no differences in functional outcomes between the patients. For tibial plateau fractures, restoration of alignment, improving the condylar width, and articular reduction remain the most important aspects of care; however, stability of the knee joint must be confirmed as well.