Above-knee amputation (AKA) has been linked to a greater risk of advanced osteoarthritis and osteopenia in the residual limb compared to below-knee amputation ^[1,2,3,4]. These patients are also predisposed to complications in the thigh region, including hip flexion and abduction contractures, heterotopic ossification, muscular atrophy of the residual limb, and skin breakdown at the stump ^[5,6]. These factors collectively pose significant challenges during total hip arthroplasty (THA), such as difficulty in achieving hip dislocation, controlling the residual limb, and accurately positioning the femoral component due to the absence of the knee and tibia. A short osteoporotic stump with a wide medullary canal further complicates implant fixation and increases the risk of intraoperative fracture. In addition, the surgical site’s proximity to the distal stump heightens the potential for post-operative infection. Functional recovery, including gait restoration and prosthesis use, is often hindered by altered biomechanics and muscle atrophy ^[7,8]. Addressing these challenges necessitates comprehensive preoperative assessment, meticulous surgical planning – including the approach, implant selection, techniques to control stump, draping strategy, and infection prevention – and a structured rehabilitation program targeting atrophied muscles.

A male patient in his early 30s presented with progressively worsening left hip pain over the past 6 months, significantly limiting his mobility and ability to bear weight through his prosthetic limb. Three years earlier, he had sustained multiple injuries in a high-impact road traffic accident, necessitating a low AKA on the left side. At that time, he also sustained a fracture of the ipsilateral femoral neck, for which he underwent safe surgical dislocation and internal fixation using headless screws. Post-operatively, he achieved initial recovery and was ambulatory with a prosthesis. However, over time, he developed a persistent, dull ache in the left hip, which intensified and became disabling. On examination, the stump was well-healed with no signs of infection or contracture, but notable gluteal muscle wasting and severe, painful restriction in hip range of motion were present. Pelvic radiographs demonstrated advanced arthritis of the left hip (Tönnis Grade 3), with femoral head collapse and retained headless screws in situ (Fig. 1). Pre-operative functional assessment using the Harris hip score (HHS) was 30, indicating severe disability ^[9].

Figure 1: Pre-operative radiograph.

A full-length radiograph of the residual stump was obtained for templating. The residual stump was long with minimal thinning of the cortices and widening of the medullary cavity. Non-contrast computed tomography of the pelvis was done to rule out any heterotopic ossification. A DEXA scan of the proximal femur region ruled out osteoporosis. Other basic pre-operative and infective workup revealed no significant abnormality.

The procedure was performed via a lateral (modified Hardinge) approach to the hip, with the patient positioned in the lateral decubitus position (Fig. 2).

Figure 2: Lateral decubitus position.

Intraoperative manipulation of the femur and hip dislocation was facilitated using a 6 mm Steinmann pin inserted into the lateral distal femur, providing leverage while minimizing interference with femoral stem placement in the medullary canal (Fig. 3 and 4). An uncemented 48 mm acetabular cup, a size 4 hydroxyapatite-coated uncemented femoral stem, and a 32 mm femoral head were implanted.

Figure 3: Steinman pin at the distal lateral femur.

Figure 4: Intra-operative manipulation by the Steinman pin.

Intraoperative stability was satisfactory. Post-operative radiographs confirmed appropriate alignment and positioning of the prosthetic components (Fig. 5).

Figure 5: Immediate post-operative radiograph.

On post-operative day 2, post-dressing of the surgical site, rehabilitation commenced with a focus on strengthening exercises targeting the hip flexors, extensors, external rotators, abductors, and adductors. Weight-bearing was deferred until the surgical wound had adequately healed and residual limb swelling had subsided to permit prosthesis fitting. By post-operative day 6, the patient reported significant relief from preoperative pain and was discharged in stable condition, with advice to continue physiotherapy at home.

At the 12-week post-operative review, the patient was permitted to resume full weight-bearing with the aid of crutches and the above-knee prosthetic limb. Follow-up radiographs at 6 months demonstrated satisfactory osseointegration of the implants, with no evidence of component subsidence or osteolysis (Fig. 6). Clinically, the patient remained pain-free on the operated side and was mobilizing independently with crutches and the prosthesis. Functional outcome, as measured by the HHS, improved markedly from a pre-operative score of 30–70 at the latest follow-up.

Figure 6: Follow-up radiograph at 12 weeks.

Patients with AKAs present unique challenges that necessitate careful consideration during preoperative planning, surgical execution, and post-operative rehabilitation. Pre-operative imaging should include the entire residual femur to assess both the remaining bone stock and medullary canal dimensions, as prolonged prosthetic use may alter bone mineral density and distal femoral morphology ^[10,11]. Patients with reduced bone density are at a higher risk of sustaining intraoperative fractures, which can delay post-operative rehabilitation ^[1,12]. In such cases, cemented implants may offer advantages. In amputees, a diminished cortical area is frequently observed at the stump end, often accompanied by widening of the medullary canal. Consequently, several authors recommend the routine use of cemented components in this population to minimize fracture risk and facilitate early weight-bearing ^[11,13]. In our case, the patient had a long residual stump with no evident osteoporosis, widening of the canal; hence, an uncemented prosthesis was chosen. In addition, a thorough evaluation of skin integrity and soft tissue quality at the stump is crucial to minimize post-operative infection risk. Beyond standard prophylactic antibiotics, some authors recommend isolating the distal stump using sterile adhesive drapes intraoperatively, as it is often considered a potentially contaminated area due to its habitual contact with the prosthetic socket ^[11,14]. We covered the end of the stump with sterile adhesive drapes to maintain asepsis. Post-operatively, consistent use of appropriate stump bandaging during rehabilitation – especially when fitting the external prosthesis – is essential to reduce the risk of surgical site infection.

Post-traumatic AKAs are frequently associated with complications, such as malunited fractures, heterotopic ossification, and soft tissue contractures. These issues may necessitate surgical interventions – including soft tissue release, excision of ossified masses, or even a greater trochanteric osteotomy – to facilitate adequate exposure and enable safe dislocation of the femoral head during THA ^[15]. Intra-operative control of the femoral stump can be achieved through various techniques tailored to the patient’s anatomy and surgical requirements. Common methods include the use of a traction pin or bone clamp applied at the subtrochanteric level, or placement of Steinmann pins along the lateral aspect of the distal femur, ensuring they do not interfere with implant positioning ^[11,16,17]. In cases where the femoral stump is short, a pin may be inserted at the level of the greater trochanter ^[10,18,19]. Bone clamps can be positioned at the peri-trochanteric or subtrochanteric regions ^[20,21,22]; however, some surgeons avoid the trochanteric area due to concerns about bone fragility. In view of the long residual stump with healthy skin, soft tissues, and preserved bone mineral density in our patient, the traction pin was placed in the distal femur. This facilitated effective manipulation of the femur while preventing interference with stem insertion into the canal. Alternatively, applying a clamp at the site of gluteus maximus insertion on the femoral shaft has been described as a technique that offers effective limb manipulation while minimizing the risk of iatrogenic fracture, particularly in osteopenic bone or in the presence of prior scarring ^[11]. Rehabilitation protocols should be tailored to the specific anatomy and muscle involvement dictated by the level of amputation. In amputees, loss of the gastrocnemius – the primary propulsive muscle in gait – necessitates increased reliance on the remaining musculature. During stance phase on the amputated side, the hip flexors, extensors, and external rotators serve as the main power generators, while the abductors and adductors act predominantly as shock absorbers, in contrast to the contralateral limb. Accordingly, beyond the standard post-operative regimen for THA, targeted stretching of the hip flexors and knee extensors is often emphasized ^[13,19]. For our patient, based on our preoperative assessment, we focused on the strengthening of hip extensors, adductors, which yielded a good functional outcome.

This report demonstrates that THA can be successfully performed in above-knee amputees by prioritizing individualized preoperative planning, intraoperative control of the stump, and tailored rehabilitation. By detailing practical intraoperative strategies and focused post-operative rehabilitation, this report offers original and practical guidance for orthopedic surgeons faced with similar complex scenarios. The case not only adds to the limited literature on THA in above-knee amputees but its broader impact lies in improving functional outcomes, optimizing perioperative protocols, and advancing clinical knowledge about surgical and rehabilitative management after major limb amputation with secondary hip arthritis.

1. Total hip arthroplasty in above-knee amputees presents unique anatomical, biomechanical, and technical challenges that require meticulous preoperative planning.
2. Full-length residual femur imaging, bone density assessment, and careful evaluation of stump skin and soft tissue are essential to reduce intra- and post-operative complications.
3. Intraoperative control of the femoral stump can be optimized using techniques, such as Steinmann pins or bone clamps, adapted to stump length and bone quality.
4. Implant fixation strategy should be guided by bone stock and medullary canal morphology, with cemented components considered to reduce fracture risk and allow early mobilization.
5. Post-operative rehabilitation must be tailored to the level of amputation, focusing on compensating for lost propulsive muscles and restoring functional gait with a prosthesis.