Hip arthroscopy after surgical hip dislocation: is predictive imaging possible?

PURPOSE: Our purpose was to study the sensitivity, specificity, and predictive values for hip adhesions, labral tears, and articular cartilage lesions in patients who had open treatment for femoroacetabular impingement, had persistent symptoms, and had both magnetic resonance arthrography (MRA) with radial slices and hip arthroscopy.

METHODS

Of 750 patients, 21 patients (6 male and 15 female patients; mean age, 28 years [range, 16 to 41 years]) with persistent groin pain after open osteochondroplasty and femoroacetabular impingement were included. The mean time between open osteochondroplasty and hip arthroscopy was 19 months (range, 4 to 79 months). At index surgery, patients had open osteochondroplasty of the femoral head-neck junction, as well as resection of the acetabular rim with reattachment of the labrum. All patients had preoperative MRA.

RESULTS

At hip arthroscopy, 1 tear of the labrum was verified on MRA. MRA showed in all patients adhesions between the neck of the femur and joint capsule, which were confirmed at arthroscopy and removed. Sensitivity of MRA for tears and adhesions was 100%; specificity, 100% and positive predictive value (PPV), 100%. For acetabular cartilage damage, sensitivity was 66.7%; specificity, 77.8%; and PPV, 63.6%. For femoral cartilage damage, sensitivity was 80%; specificity, 100%; and PPV, 20%. Postoperative alpha angles were significantly decreased. Of 21 patients, 3 had persisting groin pain.

DISCUSSION: Persistent groin pain after open osteochondroplasty of the hip could result from pathologic changes such as intra-articular adhesions with concomitant soft-tissue impingement. This pathology, as well as cartilage damage and labral tears, can be shown on MRA with radial slices.

CONCLUSIONS

Twenty-one patients with persistent groin pain after open osteochondroplasty of the hip had adhesions identified by MRA with radial slices. At hip arthroscopy, these adhesions were removed and 18 of 21 patients had relief of their symptoms.

LEVEL OF EVIDENCE: Level IV, therapeutic case series.