Benefits of negative pressure wound therapy with fat migration during revisional total hip arthroplasty in an obese patient: A case report

Abstract

Introduction: A 38-year-old African American woman presented with right hip pain and movement restriction. Her medical history included a right hip and knee arthroplasty 10 years prior, history of Slipped Capital Femoral Epiphysis and osteonecrosis of the hip. Preoperative assessment was significant for multiple comorbidities such as obesity (BMI > 38), hypertension, asthma. Patient concerns: The patient presented with right hip pain, rated 7/10, and restricted hip flexion, adduction, and abduction. Diagnosis: Recent imaging showed eccentric deterioration of the polyethylene lining of her prosthesis, acetabular hypertrophy on her right hip prosthesis, and chronic deformity of the pubic bone. Interventions: Based on these findings, a revisional total hip arthroplasty was performed. After the surgical procedure, the WoundVAC and the percutaneous drain were applied outside the tensor fascia lata to reduce seroma and hematoma formation. Postoperative pain control, antibiotics and DVT prophylaxis were given. On post-op day 3, an irrigation and debridement with delayed primary wound closure was performed under sterile conditions. Outcomes: On postoperative assessment, the wound demonstrated adequate healing without any signs of infection. Sutures and staples were removed 4 weeks post-op. Upon palpation there was no edema, effusions, temperature changes, tenderness. Clinical inspection revealed symmetrical alignment of the pelvis and hips. Range of motion testing revealed restriction beyond 80 degrees upon flexion and beyond 5 degrees of adduction and 10 degrees of abduction. The surgical site was noted to be healed at 6 weeks post-op. The patient continued to do well to date, without exacerbations. Conclusion: Obesity increases the risk of post-operative complications and wound healing failure. Therefore, Vacuum-assisted wound closure (WoundVAC), a type of negative pressure wound therapy, was applied outside the tensor fascia lata post-operatively, where the surgical incision was made. Negative pressure wound therapy facilitates wound healing by stimulating angiogenesis and promoting granulation tissue formation, which in turn can reduce the risk of surgical site infection in obese patients undergoing total hip arthroplasty. Highlighted is the mechanism of fat migration in the promotion of wound healing after preoperative weight loss and exercise.