Subtrochanteric Hip Fractures Treatment & Management

The goals of therapy for subtrochanteric fractures include the following:

• Anatomic alignment
• Early mobilization
• Effective rehabilitation

Today, treatment of these fractures in adults is almost exclusively surgical. With the improvements in surgical techniques and implants, most of the treatment goals can typically be achieved by surgical means. Current indications for surgical treatment include the following:

• Displaced and nondisplaced fractures in adults
• Fractures in patients with multiple traumatic injuries
• Open fractures
• Severe ipsilateral extremity injuries
• Pathologic fractures

In selected patients with grossly contaminated fractures and in patients who are medically unstable for surgical intervention, treatment with skeletal traction can be considered. In skeletally immature patients, traction followed by cast bracing is an accepted treatment option.

The use of indirect reduction techniques may prove beneficial in those fractures stabilized with plate fixation techniques. In 1989, Kinast et al demonstrated a lower delayed union/nonunion rate and more rapid consolidation with blade-plate fixation and indirect reduction than with blade-plate fixation via direct visualization. ^[18] As minimally invasive plating techniques evolve and improve, applications in high-energy proximal femoral fractures may become feasible and allow for a more biologically favorable approach with less soft-tissue dissection and disruption of native blood supply.

Literature regarding total hip arthroplasty (THA) for subtrochanteric fractures in elderly patients is lacking, and any conclusions must be extrapolated from data regarding THA for femoral neck fractures or intertrochanteric fractures. This body of literature suggests possible functional advantages, such as more rapid mobilization and shorter lengths of stay in select groups (eg, pathologic fractures, fractures in patients with renal disease, patients with preexisting arthritis). Thus, in the authors' view, THA in patients with subtrochanteric fractures remains controversial. ^[19]

In December 2021, the American Academy of Orthopaedic Surgeons (AAOS) released an updated clinical practice guideline for the management of hip fractures in older adults (see Guidelines). ^[20]

Even though current treatment of subtrochanteric fractures in adults is almost entirely surgical, a number of nonsurgical treatment protocols are of historic interest. In the late 1960s, cast bracing was used, but it was soon abandoned because of poor results with fractures in the subtrochanteric region. Treatment with traction was also advocated, followed by fracture bracing with a hip spica cast. At present, however, with increasing evidence of the morbidity of prolonged bed rest in elderly people or in patients with multiple traumatic injuries, nonoperative treatment methods are seldom used.

In selected patients with grossly contaminated fractures and in patients who are medically unstable for any surgical intervention, treatment with traction remains an option. It is important to realize that traction is associated with fracture malalignment problems and joint stiffness in the adult patient. However, in skeletally immature patients, traction followed by cast bracing is still a viable treatment option. ^{[21, 22]}

Surgical treatment can be divided into the following three main techniques:

• External fixation
• Open reduction with plates and screws
• Intramedullary fixation

External fixation is rarely used but is indicated in severe open fractures. For most patients, external fixation is temporary, and conversion to internal fixation can be made if and when the soft tissues have healed sufficiently. External fixation becomes complicated when significant fracture comminution extends proximally, which may necessitate more proximal stabilization to the iliac crest. ^{[21, 23, 24, 25]}

In 1984, Tencer compared the biomechanical attributes of seven different plate and intramedullary fixation devices for subtrochanteric femur fractures. ^[26] Femur-implant constructs using intramedullary devices had up to 5% torsional stiffness as compared with intact cadaveric femora tested identically, whereas plate-fixed fractures were nearly 50% as stiff. In combined bending and compression to failure, a test to simulate forces due to body weight, the intramedullary locked rods were found to support 300-400% of body weight, whereas the plate systems failed at loads of 100-200% of body weight. ^[27]

When plate fixation is chosen for fixation of subtrochanteric fractures, the traditional option is the Arbeitsgemeinschaft für Osteosynthesefragen–Association for the Study of Internal Fixation (AO-ASIF) blade plate. This implant was first used several decades ago, with variable success rates. High union rates were reported when the procedure was appropriately planned, and medial dissection was avoided. However, high rates of complications were also reported with this technique.

As a result of the complications and the technical difficulties inherent in the blade-plate technique, ^{[28, 29]} the sliding hip screw (dynamic hip screw [DHS]) and the dynamic condylar screw (DCS) evolved as treatment options. ^{[30, 31, 32, 33]} These devices were believed to allow fracture impaction, and they had the biomechanical advantages of the blade plate but with a less complicated insertion technique. Several early reports suggested good rates of fracture union and low complication rates with both devices.

Subsequently, anatomically contoured locking plates emerged as a treatment option for subtrochanteric fractures. These also feature a simplified insertional technique and can be placed via smaller incisional portals. Long-term and high-quality comparative studies of these devices versus the angled blade plate are lacking, but success rates with their use are probably similar to those with angled blade plates and are reliant on biologically favorable, indirect reduction techniques.

Intramedullary nails are emerging as the treatment of choice for subtrochanteric femur fractures. ^{[34, 35, 36, 37]} The most widely used nails are either centromedullary (contained within the medullary canal) or cephalomedullary (including those that affix to the femoral neck and head; see the image below).

Essentially all subtrochanteric fractures below the level of the lesser trochanter can be nailed with a centromedullary locking nail. For fractures with extension above the lesser trochanter (Russell-Taylor type 2), a fixed-angle device such as a blade-plate or DCS can be used, but these seem to provide less predictable results. Most type 2A and 2B fractures can be successfully treated with cephalomedullary nails, such as the Richards reconstruction nail. ^[38]  (See the images below.)

It is important to beware of the use of hip fracture implants (compression-screw cephalomedullary nails); these are not the ideal implants for most subtrochanteric fractures, because of the large amount of bone that must be removed in the trochanteric and head areas and because of the limited canal-diameter options that do not allow the use of a canal fitting nail.

Xu et al compared outcomes and complications of titanium elastic nail and open reduction with plate fixation in 67 school-aged children (age range, 5-12 years) with subtrochanteric femur fractures. ^[39]  All 67 fractures united properly, with no major postoperative complications. In the titanium nail group, 24 excellent and 15 satisfactory results were reported, compared with 19 excellent and nine satisfactory results in the open plating group. Both techniques were considered  to be safe and effective  for treating subtrochanteric fractures in this population.

Operative details

Preoperative templating is advisable. Treatment of subtrochanteric fractures is technically demanding, and the surgeon needs flexibility in the choice of implant and approach.

When proximal comminution requires the use of a fixed-angle device, detailed templating is required to ensure that an implant with the proper blade or compression screw length, as well as plate length, is chosen. When an intramedullary device is chosen, templating for length, as well as canal diameter, is necessary for proper planning. In addition, because significant comminution could make limb length determination difficult, it can be helpful to obtain radiographs of the unaffected femur with a ruler to ascertain the normal femur length.

The proximal fracture fragment is invariably flexed and externally rotated. If a reconstruction-type nail is chosen, it is particularly difficult to locate the piriformis fossa in the proximal fragment. Occasionally, a small incision with insertion of a bone hook, fracture clamp, or Schanz pin can be helpful to orient the proximal fragment.

During intramedullary nailing, the intramedullary fracture reduction tool is frequently helpful to reduce the proximal fragment for guide-wire passage. Small incisions and use of percutaneous instruments to manipulate fragment position are helpful and do not have frequently described complications. Care must be taken to maintain the reduction during reaming to avoid eccentric reaming and fracture malposition after nail insertion.

Many techniques, both percutaneous and open, have been described to aid in reduction of these difficult fractures. ^[40] Accuracy of reduction is the most important factor to offload the high stresses seen by these load-sharing implants and prevent hardware failure and subsequent nonunion. ^[41]  Open reduction, if indicated, may be facilitated by the use of cerclage wiring. ^{[42, 43]}

If a trochanteric nail or off-axis nail is chosen, the entry point for the device may be easier to localize, even with small incisions. Still, malrotation of the fracture fragments can make this task difficult. However, the insertion angle must match the valgus of the nail design to avoid frontal plane deformity, and poor insertional vectors are common with this fracture.

In addition, proximal fragment comminution makes reduction and positioning of the head and neck fragment challenging. During plating, comminution at the proximal lateral femur can make lateral start-site localization very difficult. It is frequently helpful to position a guide wire anteriorly on the femoral neck, approximating the axis of the femoral neck, to assist in proper orientation of the starting chisel in the proximal femoral fragment.

Fractures with large fragments and limited comminution can typically be reduced with traditional techniques, including lag screw fixation of fragments followed by plate neutralization. However, in the presence of severe comminution, indirect reduction and minimally invasive bridge plating techniques may preserve the soft tissues and contribute to successful union. Acute bone grafting is occasionally suggested but is most likely to be appropriate in the setting of comminution, including the medial cortical buttress along the proximal calcar region of the proximal femur in closed fractures.

In the setting of pathologic fractures, prophylactic stabilization of the entire femur may be indicated to prevent problems with multiple metastases in the same bone and facilitate possible treatment with radiotherapy. If an intramedullary device is chosen, care must be taken to ensure that adequate material for biopsy is obtained, usually with the intramedullary reamings. If necessary, open fracture reduction may be facilitated to obtain adequate material for pathologic analysis.

After intramedullary nailing, if bone quality and cortical contact are adequate, 50% partial weightbearing can be allowed immediately. With less stability, patients can perform touchdown weightbearing. After open reduction and internal fixation (ORIF) and plate fixation, minimal protected weightbearing can begin immediately but is advanced slowly, beginning approximately 4 weeks after surgery, with full weightbearing anticipated at 8-12 weeks.

Elderly patients may have difficulty with compliance with weightbearing restrictions. Such patients are slow to progress and generally avoid aggressive weightbearing on the injured extremity. As a result, most elderly patients can be safely permitted to progress to full postoperative weightbearing status. ^[11]

Common complications include the following ^{[44, 45]} :

• Nonunion
• Malunion
• Failure of fixation
• Deep vein thrombosis (DVT)
• Wound infection

Nonunion is usually accompanied by significant pain after 4-6 months with the inability to bear full weight. Some studies have associated postoperative use of nonsteroidal anti-inflammatory drugs (NSAIDs) with nonunion of long-bone fractures. ^[46] If nonunion is not obvious on plain radiography, tomography may help delineate it; occasionally, bone scanning can be helpful. In the presence of stable fixation, autogenous bone grafting can lead to successful fracture unions. In patients treated with intramedullary nails, exchange nailing with overreaming is also appropriate, with or without static locking of the new nail device.

Malunion is usually evident as a limp from shortening or rotational deformity with limitation of hip rotation. Frequently, gross rotational deformity can be detected before a patient is awakened from an intramedullary nailing procedure and can be corrected at that time. Late detection of malrotation may necessitate a derotational osteotomy of the affected bone. Shortening is often secondary to varus at the neck shaft junction and can be addressed with a valgus osteotomy.

Failure of a screw-plate device can be salvaged with a repeat plating and bone graft procedure or with second-generation nailing.

Mechanical and chemical prophylaxis for DVT should be employed appropriately after fractures of the proximal femur. Diagnostic modalities, including Doppler ultrasonography (US) and computed tomography (CT) of the chest, should be used accordingly when DVT or pulmonary embolism (PE) is suspected.

Deep sepsis may be manifested by fracture nonunion. Workup for infection involves a standard hematologic analysis, including white blood cell (WBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) level. In addition, aspiration can occasionally be diagnostic. Finally, WBC scanning can also provide information about deep infection.

Close follow-up is required after fixation of subtrochanteric fractures. The wound is checked for proper healing 7-14 days postoperatively. The patient should have monthly clinical evaluations and radiographs to monitor healing. Quadriceps rehabilitation should begin within 2 weeks postoperatively.

Most patients have significant disability for a minimum of 4-6 months. The authors suggest that impact activities may be possible at 6 months, but patients should wait a full year before returning to full contact sports. If a nonunion becomes evident, autogenous bone grafting is usually indicated, usually before 1 year has passed since the index procedure, to avoid hardware failure.