Serial clinical and MRI examinations after arthroscopic rotator cuff reconstruction using double-row technique

Rotator cuff reconstruction using arthroscopic double-row technique enables a better repair of the anatomical footprint at the tendon insertion. Objective of this serial study was to illustrate structural and functional results during recovery following double-row reconstruction. Forty-five patients with mid-sized ruptures of the supraspinatus tendon were assessed prospectively and underwent arthroscopic surgery using the double-row technique. Rupture localization, size, form, and extent of retraction were recorded intraoperatively. Clinical and MRI follow-up examinations were carried out for all patients after 6, 12, 26, and 52 weeks. A A standard protocol was used during the follow-up examinations to determine tendon integration, signal changes in the tendon, extent of bone marrow edema near the enclosed absorbable suture anchors, muscle changes. The clinical results were correlated with the MRI appearance. After 26 weeks, the Constant score (CS) showed a highly significant increase for the first time with a value of 78 (p < 0.001). Tendon integration according to Sugaya showed a left shift over time, with higher CS-values for lower Sugaya classifications. Significant improvements in strength were first measured between the 26-week and 52-week follow-ups (9-> 19/p < 0.001). Highly significant improvement (p < 0.001) of the tendon signal and the fatty infiltration was found in the same time interval. The hypotrophy showed slight improvement, while a highly significant reduction of the bone marrow edema was found between weeks 12 and 26 (p < 0.001). There were no re-ruptures after week 26. The present serial study showed that it took 26 weeks to reach a significant clinical improvement concerning CS. With regard to tendon healing, no further deterioration of the structural results occurred between week 26 and week 52 postoperative. There were slightly but not significant better clinical results according to the the Sugaya classification. However, parameter "strength" was significantly increased between weeks 26 and 52. This was consistent with a significant decrease in the signal intensity at the repaired tendon site, an additional improvement in the fatty infiltration, and the atrophy according to Thomazeau in the same time interval. I.