Bilateral Hip Dysplasia and Labral Tears

Physicians

Ronald Hugate, M.D.
Orthopedic Surgeon, Colorado Limb Consultants

Brian J. White, M.D.
Orthopedic Surgeon, Western Orthopaedics

Introduction

Hip dysplasia is a congenital condition in which the acetabulum forms incompletely in a shallow, vertical, and often anteverted position. It is more commonly seen in firstborns, females, multiples and breech position births (1,2). Individuals with hip dysplasia are usually identified during screening as infants shortly after birth when the condition can be easily treated with harnessing (1,2). On rare occasion, however, it eludes diagnosis early in life and is found in adolescents or young adults who present with hip pain (2). Because of the acetabular position in these patients, the labrum is often torn or damaged and this leads to the pain they experience upon presentation. Unfortunately, treating the labral pathology alone is rarely successful as the repaired/reconstructed labrum will continue to see excessive forces unless the hip joint deformity is corrected as well.

The hip preservation team at the Denver Clinic for Extremities at Risk (DCER) has developed a unique protocol for managing adolescents and adults with hip dysplasia and associated labral injury. Drs. Brian White and Ronald Hugate employ a staged approach to this problem, combining the advantages of arthroscopic hip surgery with minimally invasive Ganz osteotomy techniques to correct both the labral pathology and the position of the acetabulum in these patients without having to open the joint. This approach addresses all of their hip disease, resulting in a more anatomically and mechanically correct hip joint. This protocol can eliminate or delay the need for total hip replacement in the future for these young, active patients.

Case Presentation

V.M. is a 29-year-old female with bilateral congenital hip dysplasia who has suffered from increasing bilateral hip pain over the last six years. She is otherwise healthy and highly active, working as a nurse and a competitive horseback rider. Over the past year, her pain had intensified and was noted to be greater on the left side. She managed her pain with tramadol (50mg QD).

In November 2011, V.M. was referred to Dr. Brian White, co-medical director of the Hip Preservation program at DCER. A diagnostic MRI revealed the presence of bilateral labral tears. Dr. White recommended arthroscopic treatment for her labral pathology and referred V.M. to Dr. Ronald Hugate to evaluate for a possible Ganz osteotomy. Radiographs showed the left hip center edge angle of 20 degrees with a tonus angle vertically of 15 degrees; the right hip had a center edge angle of 23 degrees and 14 degrees. Dr. Hugate and Dr. White recommended that V.M. undergo staged hip arthroscopy with labral repair followed by a Ganz osteotomy. The goal of this staged approach was to reduce pain and mitigate arthritic advancement. Because the left hip was most dysplastic and symptomatic, it was recommended that this hip be addressed first, with plans to manage the right hip with a similar approach five months later.

On March 22, 2012, V.M. underwent the arthroscopic labral repair by Dr. White. The surgery revealed a massive hypertrophic degenerative tearing of the acetabular labrum from 8 o’clock to 2 o’clock and grade 3 cartilage damage of the acetabulum. This is a common injury pattern seen in hip dysplasia. The femoral head cartilage was normal, and there was a CAM lesion of the proximal femur. Dr. White addressed these issues with femoral osteoplasty, acetabular rim trimming and labral reconstruction utilizing allograft tissue (Musculoskeletal Tissue Foundation, Edison, NJ). Reconstruction of her acetabular labrum was required as her labrum was too degenerative and poor quality for a repair.

Six weeks later, V.M. underwent the Ganz osteotomy with Drs. Hugate and White to improve the coverage of the left femoral head. A single incision anterior approach was utilized for this procedure with the surgical incision proceeding distally from the ASIS, about four inches in length. Because Dr. White had addressed the issues in the joint arthroscopically six weeks prior, the Ganz procedure was extra-articular and rectus sparing. The pubic, ischial and iliac cuts were made using fluoroscopy as a guide and the acetabulum was freed up for the correction. The posterior column and pelvic ring were left intact. Under fluoroscopic guidance, the acetabulum was repositioned into its corrected position, improving lateral coverage. Screw fixation was placed to hold the new acetabular position until bony healing takes place.

Post-operatively, V.M. did well. The post-operative center edge angle was measured at 30 degrees. After six weeks, she was weight-bearing as tolerated and was prepared to start the process again for her right hip.

On August 21, 2012, V.M. underwent arthroscopy of her right hip. The arthroscopic procedure again showed hypertrophy and degeneration in the acetabular labrum with extensive tearing at the 4:30 position, grade 3 cartilage damage of the acetabulum, CAM morphology of the proximal femur, and normal femoral head cartilage. Femoral osteoplasty, acetabular rim trimming, labral reconstruction, and a shaving chondroplasty of the lateral acetabulum were performed. Six weeks later, in September of 2012, V.M. underwent the right sided Ganz osteotomy as described above.

She recovered well from the right hip surgeries and steadily progressed her weight bearing and normal activity over the next several months. Currently, the patient is eighteen months out from her surgery on the left side and one year on the right. She reports a Harris Hip Score of 75 on the left side and 65 on the right side. She has minimal pain and has been able to horseback ride again.

Discussion

Arthroscopic hip labrum reconstruction is an extremely demanding and technical procedure. For a patient with a severely degenerated, irreparable labrum it provides optimal restoration of anatomy and function and also removes a significant pain generator from the joint. Arthroscopic femoral neck osteoplasty is often performed in conjunction with the labral work. It is an important step to prevent impingement of the labral repair or reconstruction once the acetabulum is redirected with the Ganz osteotomy.

The Ganz periacetabular osteotomy has technical advantages over other pelvic osteotomy techniques historically utilized for correction of hip dysplasia (3). This technique has evolved over the last three decades into a single incision, minimally invasive approach. With the Ganz osteotomy, the posterior column and pelvic ring remains intact therefore the pelvis is stable in the immediate post-operative period (4). The technique allows for three-dimensional mobilization of the acetabular fragment to a more favorable in position, achieving adequate femoral head coverage, while preserving the stability of the pelvis. Minimal fixation is utilized and patients are able to progress to full weight bearing in a relatively short amount of time (3,5).

Conclusion

The unique approach to hip dysplasia at DCER combines the best of both worlds. The articular issues are all addressed arthroscopically. This allows for more complete visualization of the hip joint with a superior ability to find and correct issues without having to perform open arthrotomy. Because the articular work is completed arthroscopically, we are able to stay outside the joint during the Ganz procedure and leave an important quadriceps muscle — the rectus femoris muscle — attached to its native position making for a less invasive/traumatic procedure.

This exciting collaboration between our open and arthroscopic surgical experts in treating congenital hip dysplasia allows us to address these complex issues with great success resulting in superior outcomes.

References

1. Murphy SB, Ganz R, Muller ME. The prognosis in untreated dysplasia of the hip: a study of radiographic factors that predict the outcome. J Bone Joint Surg Am. 1995;77:985-989.

2. Murphy SB, Kijewski PK, Millis MB, Harless A. Acetabular dysplasia in the adolescent and young adult. Clin Orthop Relat Res. 1990;261:214-223.

3. Ganz R, Klaue K, Vinh TS, Mast JW. A new periacetabular Osteotomy for the treatment of hip dysplasias: technique and preliminary results. Clin Orthop Relat Res. 1988;232:26-36.

4. Clohisy JC, Barrett SE, Gordon JE, Delgado ED, Schoencker PL. Periacetabular Osteotomy for the treatment of severe acetabular dysplasia. J Bone Joint Surg Am. 2005;87:254-259.

5. Kralj M, Mavcic B, Antolic V, Iglic A, Kralj-Iglic V. The Bernese periacetabular Osteotomy: clinical, radiographic and mechanical 7-15 year follow-up of 26 hips. Acta Orthop. 2005;76:833-840.