Our aim was to analyze retear rates and assess the risk factors for retears & also to study changes in muscle atrophy & fatty infiltration following arthroscopic repairs of massive cuff tears with or without involvement of subscapularis (SSC).
Materials & Methods:
This retrospective cohort study had patients with massive cuff tears involving SSC in group I(n=48) compared with group II(n=50) that included massive cuff tears without SSC tears. Both the groups were comparable pre-operatively in terms of age, duration of presentation, Muscle atrophy (Occupation ratio-OR) & fatty infiltration (Global fatty degeneration index-GFDI). Assessment of pain using Visual analogue scale (VAS), Range of movement (ROM) & functional scoring using constant and UCLA scores were done pre-operatively and at final follow-up. Post-operative MRI assessment was done at 6 months to assess cuff integrity using Sugaya classification & also to note any change in muscle atrophy & fatty infiltration observed in the pre-operative MRI. Sugaya’s type 4 and 5 involving any portion of the rotator cuff was classified as retear on the post-operative MRI. MRI assessment was done by two independent observers trained in arthroscopy and sports medicine with good interobserver reliability (intraclass correlation co-efficient: 0.8-1).
We had a total of 11 retears, out of which majority of them were in group I(n=8), though the difference was not statistically significant(p=0.09). Lafosse Type IV & V tears of subscapularis, higher pre-operative GFDI, lower pre-operative OR, higher grade of pre-operative tendon retraction, diabetes mellitus were all pre-operative risk factors for retears. The ROM and clinical scores namely VAS, UCLA & Constant scores improved significantly post operatively in all patients with no significant difference between the two groups at a mean follow-up of 13.5 months. However, patients with retears achieved lower range of forward flexion, external rotation and lower constant and UCLA scores. Muscle atrophy (OR) and fatty infiltration (GFDI) progressed after repair of massive cuff tears irrespective of involvement of subscapularis(p<0.001).
SSC involvement in the massive cuff tear results in a relative higher retear rate with Lafosse Type IV & V tears, higher preoperative muscle atrophy & fatty infiltration, higher grade of pre-operative tendon retraction & diabetes mellitus as pre-operative risk factors for retears. Muscle atrophy and fatty infiltration progress after repair of massive cuff tears irrespective of involvement of subscapularis.