Femoral Head Reduction Osteotomy for Deformed Perthes Head Using Ganz Safe Surgical Dislocation of Hip - A Case Report with 3-Year Follow-up.

INTRODUCTION: Perthes disease often results in a non-spherical deformed femoral head which causes pain, dysfunction, early degeneration, and arthritis in young adults. The importance of preservation of native hip in young adults has been well proven. We report a case of deformed Perthes head treated with femoral head reduction osteotomy using Ganz safe surgical dislocation which is a technically demanding but highly rewarding surgical procedure. CASE REPORT: A 18-year-old female suffering with hip pain and limp for the past 2 years was diagnosed as sequelae of Perthes disease with femoral head deformity. Pre-operative Harris hip score was 54. The patient was planned for joint preservation surgery considering the young age. Ganz safe surgical dislocation was used to expose the hip joint and femoral head reduction osteotomy was done to recreate the sphericity of the femoral head. After 3-year follow-up, the patient had significant pain relief and restoration of function with no evidence of avascular of the femoral head. Post-operative Harris hip score was 82. The treatment of deformed Perthes femoral head remains controversial with no gold standard treatment. Femoral head reduction osteotomy allows the surgeon to reduce the size of the femoral head and restore sphericity of the femoral head preserving the blood supply and helps to improve the functional outcome of the patient. Our case report with 3-year follow-up is evidence to prove the same.
CONCLUSION: Femoral head reduction osteotomy using Ganz safe surgical dislocation is a safe and effective joint preservation surgery to treat deformed Perthes femoral head in adolescent and young adults. Copyright: © Indian Orthopaedic Research Group.

Femoral head reduction osteotomy using Ganz safe surgical dislocation of the hip is a safe and effective joint preservation surgery to treat deformed femoral head in adolescent and young adults.

Introduction

Sequelae of Perthes disease commonly manifests as deformed aspherical large femoral heads which contribute to pain, dysfunction, and early degenerative arthritis in young adults [1]. The importance of preservation of native hip in young adults has been well proven [2]. There have been very few reports of femoral head reduction osteotomy surgical procedure, the reason being the fear of avascular necrosis [3]. This report describes our experience in a private practice setting with correction of the proximal femoral deformity associated with Perthes disease by femoral head reduction osteotomy using Ganz safe surgical dislocation [4] which is a technically demanding but highly rewarding surgical procedure.

Case Report

A 18-year-old thin built (body mass index-21) young Indian lady who is a college student presented to us with complaints of the left groin pain which was insidious in onset and progressive in nature associated with limp for the past 2 years. She had no history of trauma or signs of infection. Laboratory data revealed that her white blood counts, erythrocyte sedimentation rate, and C-reactive protein were within normal limits. Her clinical findings included restricted hip abduction and terminally restricted hip flexion associated with pain. Radiological findings included deformed Perthes like femoral head (Fig. 1). Considering her age and history, clinical, and radiological findings, [5] we diagnosed her as sequelae of Perthes disease with deformed femoral head. Her pre-operative Harris hip score was 54. Hip range of movements was restricted with significant pain. Considering the young age of the patient, joint replacement surgery was ruled out, and we planned for joint preservation surgery [6]. There are many described methods of joint preservation surgery for tackling deformed Perthes head, but till date, there is no gold standard treatment [7]. Treatment alternatives were discussed with patient as part of the informed consent process, including valgus intertrochanteric osteotomy [8], hip fusion [9], and pelvic supportive osteotomy [7]. Reviewing the literature and with patient approval, femoral head reduction osteotomy [10] was planned. The senior orthopedic surgeon performed the surgery using Ganz surgical hip dislocation [11] with trochanteric flip surgical approach which gave an extensile 360* view of the deformed femoral head (Fig. 2). The central necrotic collapsed portion was identified, osteotomized (Fig. 3), and excised (Fig. 4). The mobile head fragment was repositioned to create a spherical smaller femoral head (Fig. 5) and was fixed with two 3.5 mm cortical screws at the neck level, and two more 6.5 mm cancellous screws were used to fix the trochanter. Post-operative protocol included non-weight bear mobilization for 6 weeks followed by toe touch mobilization with a crutch for 6 more weeks followed by weight-bearing as tolerated. The patient was able to walk without any aids (Fig. 6) by 3 months with Harris hip score of 82. The patient is now able to do active straight leg raises against resistance (Fig. 7), walks independently pain-free with good range of movements, including hip flexion of more than 90* (Fig. 8) after 3-year follow-up with no radiological signs of avascular necrosis of femoral head (Fig. 9).

Figure 1

Pre-operative X-ray showing deformed left Perthes head.

Figure 2

Showing intraoperative picture of deformed femoral head after safe surgical hip dislocation.

Figure 3

Showing central necrotic portion being osteotomized.

Figure 4

Femoral head after excision of central deformed portion.

Figure 5

Realigned femoral head after osteotomy.

Figure 6

Showing patient weight-bearing independently with no support.

Figure 7

Showing full active hip abduction against resistance.

Figure 8

Showing range of movement.

Figure 9

Three-year follow-up X-ray with no evidence of AVN.

Discussion

Perthes disease is a self-limiting idiopathic avascular necrosis of capital femoral epiphysis in a child [12], but sometimes results in deformed Perthes head causing pain and early arthritis.. Treatment of deformed Perthes femoral head remains controversial with no gold standard treatment. The prime aim of the treatment is to maintain the sphericity of the femoral head and to prevent secondary degenerative arthritis [13]. Early diagnosis and management can help to prevent the collapse of the femoral head, progressive femoral head deformity, and impingement. The aspherical coxa magna femoral head can be made more spherical by intra-articular osteotomy [4, 13]. Theoretically, if femoral head sphericity can be restored, then the femoral head should last much longer. The Ganz technique femoral head reduction osteotomy helps to reduce the size and restore the spherical shape of the femoral head. The surgical procedure includes Ganz safe surgical hip dislocation which is one of the unique approach of dislocating the femur preserving the vascularity of the head providing an extensile view of a hip joint compared to any other approach [14]. The meticulous attention to detail and soft-tissue handling plays a major role in the success of the procedure. Very few reports of this surgery have been found in the literature. Our experience with this procedure has shown promising results after 3-year follow-up with a significant improvement in Harris hip score and functional range of movements. The only limitation is the number of cases included in the study. Risk of avascular necrosis is significant but can be avoided if the osteotomy is performed correctly with meticulous attention in the preservation of blood supply to the femoral head. The risk of avascular necrosis in a symptomatic patient may be acceptable because there is always an option for future total hip replacement surgery.

Conclusion

Femoral head reduction osteotomy using Ganz safe surgical dislocation is a safe and effective joint preservation surgery to treat deformed Perthes femoral head in adolescent and young adults. Long-term follow-up will determine whether the excellent results will hold up and whether the progress of the disease will be altered by this osteotomy procedure. Further studies and implementation of this surgery by other surgeons and reporting their results would pave the way to femoral head reduction osteotomy of being the gold standard treatment for deformed Perthes head.

Femoral head reduction osteotomy using Ganz safe surgical dislocation of the hip is a safe and effective joint preservation surgery to treat deformed femoral head in adolescent and young adults.