The biodegradable spacer as a novel treatment modality for massive rotator cuff tears: a prospective study with 5-year follow-up.

Background: The management of massive, irreparable rotator cuff tears (RCT) is challenging and associated with high failure rates. There are no current consensus or definitive guidelines concerning the optimal surgical treatment for this devastating condition. This study was designed to confirm the long-term safety and efficacy of the biodegradable inflatable InSpace™ system in patients with massive reparable or irreparable RCTs.

Methods: In this open-label, single arm, prospective study, subjects with massive RCT underwent subacromial implantation with the biodegradable spacer. Follow-up visits were scheduled according to routine clinical practice. Shoulder function was evaluated using Total Constant Score (TCS).

Results: Twenty-four patients were treated and assessed. Four patients had partial tears, and in three of them RC repair was performed. These patients were not included in the efficacy analyses. Of the participating subjects who reached the 5-year follow-up, 84.6% of the patients showed a clinically significant improvement of at least 15 points in their score, while 61.54% showed at least 25 points of improvement. Only 10% of the treated patients showed no improvement or worsening in the shoulder score comparing to their baseline. An overall improvement in the total CS commencing at 3 months and sustained by 6 months through to 5 years of follow-up (P < 0.0001) was demonstrated.

Conclusions: We conclude that in this initial cohort, arthroscopic implantation of InSpace™ system represented an effective alternative to the existing arthroscopic procedures in patients with painful massive RCT refractory to conservative management. Further randomized controlled trials comparing the clinical and functional outcomes after implantation of the InSpace™ device are warranted.