Year : 2021 Month : October Volume : 10 Issue : 43 Page : 3683-3688,

Bipolar Hemiarthroplasty as Coxofemoral Bypass Technique in Treating Unstable Pertrochanteric Comminuted Fracture of Elderly Patients

Neetin Pralhad Mahajan1, Pramod K. Bagimani2, Kartik Prashant Pande3, Ravi Rameshbhai Dadhaniya4

1, 2, 3, 4 Department of Orthopaedics, Grant Government Medical College and Sir JJ Group of Hospital,
Mumbai, Maharashtra, India.

CORRESPONDING AUTHOR

Dr. Kartik Prashant Pande, #300, Resident Hostel, JJ Hospital, Byculla, Mumbai-400008, Maharashtra, India.
Email : kartik.pande0393@gmail.com

ABSTRACT

Background

Pertrochanteric fractures in the elderly are highly unstable and osteoporotic. Comminution of fragments and distraction fragments make union difficult owing to forces acting on the proximal hip joint. The internal fixation in these cases leads to prolonged bed rest and immobilization to prevent implant failure. The purpose of this study was to analyse the role of bipolar hemiarthroplasty in cases of unstable pertrochanteric femur fractures as bypassing forces transmission through the proximal femur.

 

Methods

30 patients with pertrochanteric fractures were randomized and operated on as bipolar hemiarthroplasty using the indigenous bipolar prosthesis between July 2017 and July 2021. The inclusion criteria were patients more than 65 years of age, Type 4 intertrochanteric fracture (As per Evans classification) AO/ OTA type 31A2.3, 31A3.2, 31A3.3. Patients with polytrauma, compound injuries, pathological fractures and medically unfit patients were excluded from the study.

 

Results

The mean age was 67 ± 5 years. The most common mechanism of injury was domestic fall comprising 80 %. The average duration of surgery from the time of injury was 3.5 ± 1.5 days. The average surgical duration was 85.5 mins. The average duration of stay in the hospital was 8.5 ± 1.5 days. Final results were calculated using the Harris Hip score with 33.3 % cases as excellent, 56.6 % cases as good and 10 % cases had fair results respectively. Follow-up was done at 6 weeks, 3, 6, 12 and 24 months.

 

Conclusions

Bipolar hemiarthroplasty in pertrochanteric femur fractures has the advantage of stable adequate fixation with early return to activities of daily living, thus preventing serious life-threatening complications.

 

Key Words

Intertrochanteric Fractures, Hemiarthroplasty, Femur, Harris Hip Score.

BACKGROUND

Pertrochanteric region of the proximal femur in the elderly sustains osteoporotic multifragmentary fracture patterns following low-grade domestic falls and associated medical diseases. They are difficult to get in contact with each other owing to available methods of osteosynthesis. Per-trochanteric femur fractures in the elderly are highly unstable and difficult to treat as the bones are osteoporotic.1 The internal fixation in these cases leads to prolonged bed rest and immobilization, to prevent the implant failure.2

Among the intertrochanteric fractures, the unstable (Type 4) fractures are more difficult to treat as well as prognosis. Osteoporosis associated with a difficult reduction in such types of fractures dictates the final outcome.3 The commonly encountered fractures in orthopaedics are pertrochanteric fractures.3 Pertrochanteric fractures with severe displacement or comminution are common in elderly patients with poor bone quality.4 Complications associated with the standard methods of internal fixation devices are high as Baumgartner et al. found 20 % of implant failure in trochanteric fractures.5

Problems that are associated with the internal fixation of unstable pertrochanteric fractures in elderly patients with osteoporotic bones are excessive collapse, loss of fixation, and cut-out of the lag screw, which result in poor function.

For unstable osteoporotic trochanteric fractures, hemiarthroplasty using cone prosthesis can transfer the axial load from the hip to the middle femur, which leads to early postoperative weight-bearing.

For early postoperative weight-bearing, rapid rehabilitation and to avoid the excessive collapse at the fracture site, some surgeons have recommended replacements for the treatment of unstable pertrochanteric fractures.

The purpose of this prospective study was to evaluate the functional and clinical outcomes of bipolar hemiarthroplasty as a primary treatment for unstable pertrochanteric femur fractures in elderly patients.

METHODS

This study is a retrospective study where 30 cases of unstable comminuted pertrochanteric fractures from the inpatients with bipolar hemiarthroplasty were studied over between July 2017 and July 2021 at a tertiary care hospital in Mumbai. The inclusion criteria were patients more than 65 years of age, unstable type 4 intertrochanteric fracture as per Evans classification,6 AO/ OTA type 31A2.3, 31A3.2, 31A3.3. Patients with ambulatory status before the fracture were selected for study to know the recovery of pre-injury functions. Patients with polytrauma, medically unfit, patients with cardio-respiratory distress and allergic to cement were excluded from the study.

Pre-operative data included: Age, sex, side, fracture type and mode of injury. Post-operative data included time to full weight bearing, average hospital stay and complications. The patients provided written informed consents.

All surgical procedures were performed by the same surgical team as soon as the condition of the patients was stabilized, usually within 3-4 days after their admissions.

The operation was performed by using the posterolateral approach, with the patients in the lateral decubitus position. The femoral head and neck were removed. Meticulous care was taken to preserve the integrity of the greater trochanter, abductor muscles, and all the vascularized bone fragments. The femoral medullary canal was then reamed to the appropriate stem size and diameter. Trial reductions were performed to determine the exact length that would provide the desired tension and tissue balancing of the abductor muscles and an equal leg length. Careful restoration of neck length, offset and version to maximize the stability of the hip joint, was also performed during the trial. Both cemented femoral stem prostheses were used (Fig. 2). The lesser trochanter was not removed. Loose osteoporotic fragments were removed. The greater trochanter was reduced and stabilized by using the tension band by wiring technique after hip reduction or it was just sutured near the prosthesis (Fig. 3). The gluteus medius muscle and vastus lateralis were sutured to their anatomical locations by using anchor sutures, if necessary. Fascia lata was tightly closed over a suction drain. Post-operative radiographs were obtained [Fig. 5 & 6]

Patients were ambulated full weight bearing on the first post-operative day. (Fig. 4) Complications such as dislocation, infection, fat embolism, bedsore and hyponatremia were monitored. The sutures were removed on day 12 and the patients were discharged.

They were followed up at 6 weeks, 3 months, 6 months and 12 months (Fig. 7). Clinical evaluation was done according to Harris Hip score. (Table -1) Anteroposterior radiographs of the hip were analyzed at each follow up to note any evidence of loosening, shortening and resorption.