Objectives:
Recent studies have highlighted that the subacromial bursa, a tissue traditionally discarded during rotator cuff surgeries, has significant regenerative potential. The premise is that processing and applying this tissue to the repair site during surgery could enhance healing and improve procedural success rates. However, further research is essential to validate whether augmenting rotator cuff surgery with subacromial bursa tissue enhances healing outcomes and surgical efficacy. This prospective randomized clinical trial (RCT) aimed to evaluate the effects of bursa augmentation on patient-reported outcomes and MRI findings after arthroscopic rotator cuff repair surgery. We hypothesized that bursa augmentation would improve outcomes compared to standard rotator cuff repair.
Methods:
Patients undergoing rotator cuff repair of a posterosuperior rotator cuff tear participated in this IRB-approved, longitudinal, double-blinded, randomized controlled trial (RCT). All participants underwent a transosseous equivalent double-row rotator cuff repair, during which a subacromial bursectomy was performed to allow for tear visualization. Participants were randomly assigned to one of two groups: 1) Cases: patients who received reimplantation of minced autologous bursa tissue to the surface of the rotator cuff repair at the completion of the repair, and 2) Controls: patients who underwent standard rotator cuff repair surgery. Pre-operative tear data was recorded, and clinical follow-up was conducted at 2 weeks, 6 week, 3 month, 6 months, 12 months, and 24 months. Self-reported outcomes were measured using the ASES, SST, and PROMIS questionnaires. At a minimum of 6 months after surgery, magnetic resonance imaging (MRI) was performed and evaluated using the Sugaya classification and measurements of supraspinatus tendon thickness. To compare self-reported outcomes, a repeated measure mixed-model analysis of variance (ANOVA) was conducted, with "Bursa" as the between-subjects factor and "Time" as the within-subjects factor. For the MRI results, differences in supraspinatus tendon thickness between the cohorts were analyzed using a Student’s t-test. The Sugaya classification scores were dichotomized into "not healed" (Score ≥4) and "healed" (Score ≤3), and the odds ratio of healing was compared between the groups. Statistical analyses were conducted at a significance level of α = 0.05, with a Bonferroni correction.
Results:
Sixty-seven patients (34% female) participated in the study. Baseline demographic details of the participants are provided in Table 1, and show no significant differences between groups.
Self-reported Outcomes:
Specifically, self-reported outcomes in study visits prior to 6 months showed better results in cases (Figure 1). However, the differences did not reach statistical significance, and the magnitude of differences was smaller than the MDC of the corresponding measures (ASES (Diff., MDC) = (3.2, 9-12), SST = (0.045, 2-3), and PROMIS = (2,3-4)). At follow up visits up to two years, clinical outcomes continued to improve in both groups, and were not significantly different (Figure 2).
MR Outcomes:
While the MRI outcomes did not reveal any statistically significant differences between the study groups, the odds of healing were slightly higher in the treatment group (86%) compared to the control group (83%). Moreover, the treatment group exhibited greater supraspinatus thickness (5.4±1.8 mm) than the control group (4.6±2.5 mm)(Figure 3).
Conclusions:
While not statistically significant, overall, the current results are encouraging as they could suggest that bursa augmentation could improve early outcomes after arthroscopic rotator cuff repair. However, given the findings’ non-significance, the practical use of such augmentation still needs to be determined. Given an encouraging trend in the data, future studies with larger sample sizes, longer follow-ups, and more objective and quantitative outcomes might be instrumental in detecting the potential benefits of this logically sound procedure, which could improve shoulder health and function long-term.
