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.

Prospective clinical study of a novel biodegradable sub-acromial spacer in treatment of massive irreparable rotator cuff tears.

PURPOSE: The purposes of this prospective non-randomized study were to confirm the feasibility of the biodegradable sub-acromial spacer (InSpace™) implantation in patients with massive irreparable rotator cuff tear and to determine the safety profile and functional results 3 years post-implantation. METHODS: Twenty patients were implanted with the InSpace™ device and assessed up to 3 years of post-implantation. Improvement in shoulder function was assessed using Constant score, while ease of use of the system was recorded by surgeons as were device-related adverse events. RESULTS: Twenty patients were available for assessment. Implantation was performed arthroscopically in all patients, and a range of deployment time was 2-20 min. The mean total Constant score increased from 33.4 to 65.4 points at 3 years. There was an improvement of 6.4 points in subjective pain score which commenced at 1 week post-operatively and was sustained until 3 years of follow-up. Also activities of daily living and motions commenced improvement by 9.4 and 7.7 points, respectively. Improvement in power was only evident at 18 months of follow-up but was sustained at 3 years. CONCLUSIONS: Arthroscopic deployment of a co-polymer biodegradable spacer (balloon) into the sub-acromial space for an irreparable rotator cuff tear was found to be low-risk and simple procedure associated with improvement in shoulder function and low rate of complications. LEVEL OF EVIDENCE: IV; therapeutic case series.