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    The Challenges of Subtrochanteric Fracture Management

    In the debut of our new quarterly column X-ray Forensics, orthopaedic trauma specialist Dr. William Cross discusses the challenges with the management of an active male patient who sustained a subtrochanteric fracture of his right hip and how the case was finally resolved.

    Author

    William W. Cross III, MD

    Disclosures

    The author has no disclosures relevant to this article.

    Case Presentation

    A 43-year-old male patient presents with a suspected hip fracture following a fall at home. Radiographs indicate he has a right subtrochanteric fracture of the hip, reverse oblique (Figure 1).


    Figure 1. Comminuted reverse oblique fracture of the right proximal femur.

    A subtrochanteric hip fracture can be devastating, particularly for older patients – these fractures often trigger a downward spiral in the patient’s health, ending in death. As the population ages, surgeons can expect to see more of these fractures.

    It is imperative, therefore, for orthopaedic surgeons to understand the optimal treatment of subtrochanteric fractures to prevent significant morbidity and mortality and help their patients recover to their prior level of activity.

    In general, the objective of treatment is to reduce the fracture while avoiding varus alignment. Equipment typically needed to achieve this surgical goal includes a fixed-angle device (blade plate) or medullary nail. Sliding hip screws are contraindicated with many of these fractures.

    Initial Treatment

    The orthopaedic surgeon who operated on this patient opted to utilize a short medullary nail to repair this fracture. This could be mistake number 1, although data for the use of long and short nails in this fracture pattern are not clear. Most trauma surgeons, however, would use a long nail in this situation.

    Open reduction is encouraged to optimize the reduction when closed/percutaneous attempts fail. In this patient, open reduction was achieved with use of a cerclage wire. As a general rule, cerclage wires are poorly tolerated around the proximal femur and their use should be minimized in this anatomic area when doing a trauma reconstruction. Their use in the shaft, when applied in a biologically friendly manner, can be advantageous.

    The imaging (Figure 2) depicts the use of significant intraoperative traction with this patient. Overuse or misuse of traction can cause transient peroneal and pudendal palsies, and although it can be beneficial, it should be used only when needed and then released. Particular caution is needed with a fracture table; it’s easy to forget the degree of traction that’s being exerted.


    Figure 2. Although no AP pelvis film is available, it appears that the fracture reduction is acceptable, with good sagittal and coronal alignment. The appearance of the cerclage cable is an indication that this case was difficult and other attempts at reduction failed.

    Outcome of Initial Treatment

    The patient presented 3 months following surgery with complaints of worsening left hip pain (Figure 3). His weight-bearing was protected for 6 weeks after the injury. He noted an 8-week pudendal nerve palsy that was continuing to improve.


    Figure 3. Implant failure at 3 months from initial surgery. Note that the failure is in the zone of the cerclage wire, which may represent a lack of fracture biology needed for healing.

    What Went Wrong?

    When analyzing the failure, 3 potential pitfalls are evident:

    • Excessive soft-tissue disruption from application of the proximal femur cables
    • Use of a short medullary implant with interlocking screws in close proximity to the fracture
    • Sustained traction leading to the pudendal nerve palsy

    Revision Procedure

    In the revision procedure for this patient, the surgeon’s goals should be to address deficiencies and restore the mechanical axis, which is now in varus alignment.

    Infection may be playing a role as well, and therefore the surgeon should also order a C-reactive protein level, an erythrocyte sedimentation rate, and white blood cell count.

    Surgical intervention is again indicated for this fracture, with application of a fixed-angle device (blade plate or medullary nail). The surgeon should have autograft material available to augment the surgical site (Figure 4).


    Figure 4. Revision fixation of the subtrochanteric nonunion using a proximal femur locking plate. Sagittal and coronal alignment have been restored.

    Outcome of Revision

    Fortunately, all laboratory tests were negative for infection and surgery was scheduled.

    Two important thoughts about this revision surgery:

    • Autograft was utilized, but instead of fresh autograft from the proximal tibia (my preferred site) or the iliac crest, local autograft from early callous was utilized instead. I prefer to use autograft from intramedullary areas away from the zone of injury.
    • My preferred implant in this case would be a blade plate or revision/exchange nailing. Although this implant is indicated for this fracture type, its application may be challenging. In my hands, a 95° blade plate would be best utilized in this situation.

    Six months after surgery, the patient presented with new onset pain in right hip (Figure 5). He had just started to resume some light jogging and biking.


    Figure 5. Plate failure at the nonunion site. Note that the location of failure is at the same site as the previous failure.

    What Went Wrong?

    The failure of the second procedure is likely due to 2 issues at the non-union site: lack of a biologically favorable environment for healing and minimal to no interfragmentary compression.

    Local callous bone may not be  the best choice in this situation. In non-unions with oligotrophic or atrophic characteristics, I prefer fresh autograft harvesting due to its proven osteogenic benefit.

    In addition, the proximal femur locking plate may have not been the best implant choice. Its application is challenging and the addition of significant interfragmentary compression, although possible, is again, challenging. As noted previously, a 95° blade plate would have been my first choice for revision.

    Re-revision Procedure: Solving the Problem

    The patient was referred to our institution for a re-revision procedure (Figure 6).


    Figure 6. 95° blade plate fixation of the subtrochanteric non-union. Note the correction of the mechanical axis into slight valgus and interfragmentary compression via lag screws.

    Two primary deficiencies needed to be addressed:

    • Lack of a favorable, biologic environment, which we would address with an autograft. The autograft can be taken from the iliac crest, proximal tibia, or other sites. We elected to harvest the autograft from the proximal tibia, yielding 20 mL of autograft material.
    • Alignment of the mechanical axis, which we determined should be corrected into neutral or slight valgus alignment. We accomplished this by applying maximal compression during the procedure with clamps, an articulated compression device, and interfragmentary lag screws

    We also repeated the C-reactive protein level, an erythrocyte sedimentation rate, and white blood cell count to ensure the patient did not have new-onset infection. Fortunately, he did not.

    In addition, we evaluated the patient’s endocrine status, testing his vitamin, parathyroid hormone, and testosterone levels. All were within normal limits. It is well established in the literature that a significant number of trauma patients in general and those with non-unions in particular have underlying endocrine disorders. Many of these disorders are simply vitamin D deficiencies that can be addressed with dietary supplementation.

    The patient was placed on protected weight-bearing for 3 months, and was supplemented with calcium and vitamin D (although that is not mandatory). To maximize the bone-healing environment, our standard in this population (as well as others) is to provide supplementation until adequate healing is identified.

    Outcome of Re-revision Procedure

    Fifteen months after the third treatment, the patient had regained full function and was biking and hiking without pain. He had some mild complaints of distal thigh pain and trochanteric bursitis. He underwent hardware removal of all implants at 2 years postoperatively, with immediate pain relief (Figure 7).


    Figure 7. At 2 years, the patient demonstrated solid union and restoration of all activities without pain. He had mild distal thigh pain and mild trochanteric bursitis and underwent hardware removal at that time. He had immediate resolution of pain and resumed full activities shortly afterwards.

    Key Takeaway Points

    • Biologically friendly approaches to the proximal femur are crucial. Although cerclage wires and cables may play a role in fracture reduction, the surgeon must exercise great care in their application. An open-assisted reduction is encouraged to optimize the reduction and outcome with fractures that prove challenging to address closed.
    • Adding biology to non-unions may offer significant advantages to healing. This can be accomplished with autograft from the proximal tibia (author’s preference), iliac crest, or the Reamer Irrigator Aspirator (RIA) (Synthes, Paoli, Pennsylvania).
    • Mechanical axis correction is essential. Many non-unions may have subtle mechanical axis deviations that would benefit from correction. The proximal femur is particularly susceptible to varus malalignment and surgeon should avoid this deformity in proximal femur fracture fixation.

    Author Information

    William W. Cross III, MD, is an orthopaedic traumatologist and an Assistant Professor of Orthopaedics at Mayo Clinic, Rochester, Minnesota.