Subacromial space volume in patients with rotator cuff tear: The effect of surgical repair.

OBJECTIVE: The aim of this study was to evaluate the effect of the rotator cuff tear repair on subacromial space volume.

METHODS: We retrospectively identified 21 eligible patients (5 males and 16 females; mean age: 56.4 (range; 46-71) years) who had shoulder arthroscopy for unilateral full-thickness small to medium rotator cuff tear and normal controlateral shoulder joint. The mean follow-up time was 16.1 (range; 12-25) months. Preoperative and postoperative 1 year bilateral shoulder MRIs and Constant scores were reviewed. Subacromial volume was calculated by using Osirix software. Pre-, postoperative and healthy side (contralateral control group) subacromial volumes were recorded. Paired sample and t-tests were used to compare the pre- and postoperative groups. Independent sample t-tests were used to compare the healthy and pre- and postoperative groups. The correlation between the changes in the subacromial volume and the shoulder Constant score were analyzed using Pearson correlation analyses.

RESULTS: The mean subacromial volume of the preoperative group was 2.95 cm3 (range; 1.53-4.23) and the postoperative group was 3.59 cm3 (range; 2.12-4.84). The volume increase was statistically significant (p < 0.05). The mean subacromial volume of the control group was 3.93 cm3 (range; 2.77-5.03), and the difference between the preoperative group and the control group was statistically significant. There was no significant difference found between the postoperative group and the control group (p = 0.156). There was no significant correlation found between the volume and the constant score changes (r = 0.170, p = 0.515).

CONCLUSION: The subacromial space volume significantly decreases in full-thickness rotator cuff tears smaller than 3 cm and the surgical repair increases the subacromial volume significantly.

LEVEL OF EVIDENCE: Level IV; Diagnostic Study.