Hip arthroscopy has experienced a dramatic increase in popularity, largely resulting from improvements in techniques and technology.1,2 As with any procedure, there are complications associated with arthroscopy of the hip. These include neurapraxia, iatrogenic cartilage and labral injuries, postoperative bleeding, perineal skin necrosis, infection, intra-articular instrument breakage, intra-abdominal fluid extravasation, avascular necrosis, and femoral neck fracture.1-4 Many of these have been attributed to the expected learning curve seen with any new procedure, and are less likely to occur as surgeons become more familiar with the procedure.1 One rare but serious complication is anterior dislocation of the hip.5-7
We present a patient who experienced an anterior hip dislocation and instability after hip arthroscopy, and was successfully treated with an anterior capsuloligamentous reconstruction. The patient provided written informed consent for print and electronic publication of this case report.
Case Report
An otherwise healthy 37-year-old woman presented to our clinic with a 6-month history of right groin pain and an occasional popping sensation during activity, which was unresponsive to hip-specific physical therapy. On physical examination, she was 5 ft 10 in tall, weighed 150 lbs, and appeared in excellent physical condition. She had no signs of systemic ligamentous laxity. She had an otherwise normal musculoskeletal, neurologic, and vascular examination in her bilateral lower extremities. She had a mild antalgic gait on the right leg.
The affected right hip could be flexed painfully to 120º, extended to 0º, adducted 20º, and abducted 45º. At 90º of flexion, her right hip could be externally rotated 30º and internally rotated 20º. Internal rotation during hip flexion beyond 90º caused sharp pain in the groin. Her normal left hip could be flexed to 120º, extended to 0º, adducted 30º, and abducted 60º. At 90º of flexion, her left hip could be externally rotated 50º and internally rotated 30º. She had negative Ober tests bilaterally but had tenderness along the right iliotibial band. She had negative Patrick and Gaenslen tests bilaterally. She had no tenderness in the area of either greater trochanter.
Imaging evaluation included plain radiographs and a magnetic resonance arthrogram (MRA) of the right hip. The plain radiographs showed signs of femoroacetabular impingement, but no joint space narrowing, no dysplasia, and no retroversion of the acetabulum (Figures 1A, 1B). The MRA showed a degenerative peripheral tear of the anterosuperior labrum without significant cartilage wear (Figure 2).
Based upon her findings on physical examination and imaging, we recommended arthroscopic treatment of her right hip pathology. Thirteen months after initial presentation, we performed a right hip arthroscopy with the patient in the supine position. Through modified anterior and anterolateral portals, we used electrocautery to perform a capsulotomy from the 9 o’clock to 12 o’clock positions. A central compartment diagnostic arthroscopy showed mild degenerative fraying of the labrum from the 9 o’clock to 12 o’clock positions without signs of detachment. There was grade III chondral fraying near the articular margin in that same arc. The femoral articular cartilage appeared normal, as did the ligamentum teres. We used a shaver to gently débride the torn labrum down to stable tissue. The frayed cartilage on the acetabulum was also gently débrided.
Traction was released and the hip was flexed. Minimal capsular release and débridement were performed for adequate visualization of the peripheral compartment. A diagnostic examination revealed a significant cam-type impingement lesion from the 12 o’clock to 6 o’clock positions. We performed a femoral neck resection, with a proximal-distal dimension of 15 mm and a depth of 7 mm. A dynamic fluoroscopic examination of the hip joint showed no signs of impingement. In accordance with our standard protocol, the anterior capsulotomy was not repaired.
Postoperatively, the patient was instructed to perform toe-touch weight-bearing with crutches for 2 weeks and to advance to full weight-bearing over the next 2 weeks. She did not use a hip orthosis. She was also advised to avoid combined hip extension/external rotation maneuvers for the first 4 weeks. She took part in a formal hip-specific physical therapy program for a total of 12 weeks. She was seen in clinic at 2, 6, and 12 weeks postoperatively and appeared to have had a typical, uneventful course. We advised her to gradually return to normal activities as tolerated at the 12-week visit.
Four months after the procedure, the patient returned to our clinic for evaluation after a right hip dislocation. Two days prior, she was at a school function with her child and experienced sudden pain and inability to bear weight after she extended and externally rotated her right hip in a low-energy manner. She was taken to an emergency room and found to have an anterior dislocation of the right hip (Figure 3), which was concentrically reduced under anesthesia.
