Capsular Healing in Interportal and Periportal Capsulotomy Methods of Hip Arthroscopy

Objective To evaluate the midterm outcomes and the capsular healing in patients who had interportal capsulotomy versus periportal capsulotomy of hip arthroscopy. Methods Retrospectively reviewed 33 patients with labral tear received hip arthroscopy, with an average age of 41 (27-67) years, including 13 cases of Cam deformity and three cases of Pincer deformity. All patients had positive sign of flexion adduction internal rotation or flexion abduction external rotation. With MRI and radiographic (CT, X plain) imageological examination. MRI showed that all patients had labral tear. Radiographic finding (CT, X plain) showed the pathological changes of acetabular and femoral neck osteophyte. One group with 23 patients were treated with periportal capsulotomy. Another group with 10 patients were treated with interportal capsulotomy. All patients did not close the capsule. Clinical outcomes were measured with the Hip Outcome Score Activities of Daily Living (HOS-ADL) and the modified Harris Hip Score (mHHS), patient satisfaction measured with visual analogue scale (VAS). The healing of the capsule was evaluated by MRI. MRI showed continuous capsular indicated healing, discontinuous capsular indicated unhealing. Postoperatively 6 months, mHHS and HOS-ADL were obtained. Randomized controlled trials were used in this study for analysis. Results All patients were followed up with average time of 9.3 months(3-29 months). The postoperative symptoms were obviously relieved, the VAS decreased from (4.9 +/- 0.6) to (1.2 +/- 0.2) after 3 months postoperative. Follow up 6 months post-operation, patients in the interportal group, the mHHS and HOS-ADL scores improvement were respectively 69.4 +/- 9.3 & 70 +/- 8.8 pre-operation, and 92.5 +/- 5.0 & 86.6 +/- 5.4 post-operation (P < 0.05); Patients in the periportal group, the mHHS and HOS-ADL scores improvement were respectively 69.9 +/- 15.8, 68.1 +/- 15.0 pre-operation, and 90.1 +/- 9.3 & 86.7 +/- 7.9 post-operation (P < 0.05).The differences were statistically significant. Six months after operation, MRI showed that 23 patients with periportal capsulotomy, the capsule have healed, without other complications. Three of the ten patients with interportal capsulotomy were healed and seven were not. Conclusion Interportal and periportal capsulotomy had good outcomes. The technique of periportal capsulotomy had little damage to the joint capsule. Although the capsule did not close, the capsule healed well in postoperative follow-up. The nonunion rate of the joint capsule was high in the interportal capsulotomy without close the capsule.