Summary

Mesenchymal stem cells enhance the healing of the sutured supraspinatus tendon to its humeral footprint.

Abstract

Introduction

The study was conducted as prospective randomised blinded and controlled. The objective was to demonstrate the effect of concentrated bone marrow stem cells (MSCs) to the healing of the sutured tendon of the supraspinatus muscle in comparison to the same procedure performed without MSCs. We have postulated the hypothesis that MSCs enhance the healing of the sutured supraspinatus tendon to its humeral footprint.

Material And Methods

Between 2012 and 2015, we included prospectively in the study 50 patients selected at random into two groups who met the indication criteria for the isolated supraspinatus rupture surgery. 25 patients in Group I received MSCs filled in collagen scaffold into the tendon-bone contact point (footprint) at the site of the suture during surgery. A control group of 25 patients was treated with same open suture technique but without the use of MSCs (Group II). Clinical assessment of patients were done by blinded investigators pre-operatively, 3 months, 6 months and one year after the surgery and included physical examination of the shoulder, evaluation of the pain intensity according to the visual analogue scale (VAS), questionnaire of ASES (American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form) and the Constant score. All patients underwent MRI examination 1 year post-operatively. These findings were compared with the pre-operative results. All the results were statistically analyzed (Student´s t-test; p = 0,05).

Results

13 cases (52 %) in Group I showed significantly better clinical outcomes during the whole 1 year follow-up in comparison to the preoperative examination. In Group II 11 patients (44 %) showed improvement during the whole follow-up period. The average values preoperatively were in Group I: 3 points for the VAS score; 43 points for the Constant score; 45 points for the ASES score. In Group II the mean VAS score preoperatively was 3 points, the Constant score 45 points, and the ASES score 48 points. 6 months postoperatively average values in Group I were: 1 point for the VAS score; 72 points for the Constant score; 82 points for the ASES score. In Group II we found 1 point for the VAS score, 68 points for the Constant score, and 77 points for the ASES score. Comparing results preoperatively and 1 year after the surgery, in the Group I p-value for the VAS was 2,77x10-10, for the Constant score 2,25x10-7, and for the ASES score 6,48x10-8; in the Group II p-value was 1,70x10-6 for the VAS score, 0,000101 for the Constant score, and 0,000157 for the ASES score. When compared results between both groups one year postoperatively, p-value for the VAS score was 0,0176, for the Constant score 0,0355, and for the ASES score 0,0846.
The MRI findings at 1 year follow-up showed fully healed and well-integrated tissue of the rotator cuff tendon attachment in 17 patients (68 %) in the Group I, but only in 9 patients (36 %) in the Group II.

Conclusion

We have accepted the hypothesis that MSCs enhance the healing of the sutured supraspinatus tendon to its humeral footprint.