This study was prospective and included 60 consecutive patients with medium full-thickness RCTs who were treated with the TSB or MSB technique in our institute between December 2018 to December 2019. Of the 60 patients, 10 (17%) were lost to follow-up before 1 years after surgery, missed the radiologic evaluation at 1 year after surgery, or refused to participate in this study. The patients who met the inclusion criteria were assigned according to a table of random numbers to one of two groups depending on the surgical repair technique. The TSB technique was used in 24 of 30 consecutive shoulders and the MSB technique was used in 26 of 30 consecutive shoulders. All the surgeries were performed by the same surgeon. The study was approved by the local ethics committee (QYFYWZLL26271). Both verbal and written informed consent were obtained by all participants. We prospectively followed up the patients.
The medium-sized RCTs were preoperatively diagnosed by magnetic resonance imaging (MRI) and the tear was identified and included in our research through direct intraoperative arthroscopic exploration (Fig.1). The inclusion criteria were (1) 1- to 3-cm tears in either the coronal plane, measured and confirmed intraoperatively, (2) failure of 3-month conservative treatment, (3) and completion of the 12-month follow-up with adherence to the rehabilitation plan. According to the classification of DeOrio and Cofield, tears with an anterior-to-posterior length of less than 1 cm, 1 to 3 cm, 3 to 5 cm, and greater than 5 cm were categorized as small, medium, large, and massive, respectively
The exclusion criteria were (1) history of an operation on the same shoulder; (2) any other pathological change that required attention during arthroscopic surgery (an RCT involving the subscapular tendon and biceps tendon injury); (3) and failure to follow the postoperative rehabilitation protocol and/or a lack of regular follow-up; (4) full-thickness supraspinatus tears with an anterior-posterior dimension of less than 1 cm or greater than 3 cm; (5) workers’ compensation claims.
All procedures were performed with patients in the lateral supine position under general anesthesia. A shoulder traction device (Spider 2; Smith & Nephew, Andover, MA, USA) was used to maintain the arm in 20° of flexion and 30° of abduction. A posterior portal was established for initial assessment of the joint. An anterior portal through the rotator interval was established as the working portal for intra-articular debridement. Posterior and posterolateral portals were used mainly for the standard 30 angled 4-mm arthroscope (the viewing portals), whereas anterior and anterolateral portals were used for the instruments (the working portals). After acromioplasty, adequate visualization, preparation, and tendon release, the upper surface of the greater tuberosity was widely abraded with a shaver; all soft tissue was removed to create a bleeding cancellous bone bed. Then, 1 4.5-mm bioabsorbable anchor (Smith & Nephew,USA) loaded with 2 No. 2 nonabsorbable braided sutures, was inserted in the medial side of the cuff footprint of the humeral head (medial row).
For the TSB repair, 4 suture limbs from the medial anchor were passed through the torn tendon using a Scorpion suture passer (Arthrex), and the limbs were tied in a horizontal mattress fashion to form 2 knots. To establish the lateral row, the suture limbs of the medial-row anchor were crossed over the tendon and fixed laterally by 1 knotless anchor (4.5-mm Bio-PushLock; Arthrex, USA). Lateral anchors were then inserted perpendicular to the cortical surface of the humerus 5 to 10 mm distallateral to the lateral edge of the greater tuberosity. The free suture tails were totally appressed to the side of the tendon synovial bursa (Fig. 2) (Fig. 4a).
For the MSB group, we created a new lateral portal; the Scorpion suture passer (Arthrex) with a No. 2 polydioxanone suture (PDS2) was passed through the torn tendon through the new lateral portal. The suture gripper was used to pull out the PDS2 and 1 limb of the medial anchor suture through the anterolateral portal, and the limb and tendon suture tail were tied to the PDS2. The PDS2 was then pulled out through the original portal, the anchor and tendon suture limbs thus passed together through the torn tendon in the articular-to-bursal direction (Fig. 3a). For the second passage, the Scorpion suture passer (Arthrex) with a PDS2 was passed through the cuff and another tail of the tendon suture and the unpassed limb of the medial anchor suture were retrieved through the lateral portal using the method described above (Fig. 3b). We repeated the above steps until 2 limbs of the second anchor suture and the second tendon suture passed together through the torn tendon (Fig. 3c). The medial-row suture limbs were temporarily untied. Before tying of the horizontal mattress stitch in the medial row, the 4 free limbs of the 2 tendon sutures pulled the torn tendon back to footprint and were fixed to the lateral aspect of the greater tuberosity using a lateral row. The limbs of the tendon sutures were separated and appressed to the side of the tendon synovial bursa (Fig. 3d). After confirming that the tension was sufficient and fixation was stable, the 2 sutures of the medial row were knotted and the free tails were cut off (Figs. 3e) (Fig. 4b).
Clinical outcome evaluation
Evaluation indexs were monitored from the preoperative period until 12 months after operation by two independent observers. Range-of-motion was assessed through the shoulder turntable measuring instrument preoperatively and at 3, 6, and 12 months postoperatively. Clinical outcomes were evaluated with the visual analog scale (VAS) score for pain, University of California–Los Angeles (UCLA) score, Constant-Murley shoulder score and American Shoulder and Elbow Surgeons (ASES) score for functional outcomes in the form of a questionnaire preoperatively and at 3, 6, and 12 months postoperatively.
The routine preoperative diagnostic examinations included shoulder radiographs (anteroposterior, true anteroposterior, and axillary views), MRI, and B-US. Routine postoperative MRI and B-US were performed at 12 months postoperatively. Oblique coronal, oblique sagittal, and axial views were obtained with a 3.0-T MRI unit (Siemens Medical Solutions, Erlangen, Germany) and evaluated by a radiologist.
Rotator cuff integrity was evaluated with MRI using the radiographic grading criteria of Sugaya et al. Grade I and II: RCTs have sufficient cuff thickness; grade III: RCTs have insufficient cuff thickness without discontinuity; and grade IV and V: RCTs have cuff discontinuity suggesting small tears and large tears, respectively. Rotator cuff integrity was evaluated by 3 sports medicine surgeons and was determined by a majority consensus.
Rotator cuff integrity was evaluated on B-US using the grading system proposed by Barth et al as follows: grades I and II, sufficient thickness of >2 mm; grade III, insufficient cuff thickness of <2 mm without discontinuity; and grades IV and V, presence of discontinuity suggesting small and large tears, respectively.
Postoperative rehabilitation was achieved equally for both groups. Routine postoperative outpatient follow-up visits were conducted at 2 weeks; 6 weeks; and 3, 6 and 12months postoperatively. In the first 4 to 6 weeks, shoulder immobilization was maintained with an abduction brace that limited internal rotation of the affected arm to 30° to 40° and abduction to 30°. Active elbow flexion and extension, active forearm supination and pronation, and active hand and wrist motions were encouraged on day 1 postoperatively. After 4 to 6 weeks, the brace was removed and therapist-supervised active and passive ROM was initiated. After 3 months, active resistance musclestrengthening exercises were begun. From the sixth month, full use of the shoulder was permitted.
All results are expressed as mean ± standard deviation. The reliability of postoperative indexs were tested by the intraclass correlation coefficient with the 95% confidence interval, which was used to evaluate the reproducibility of measurements. An intraclass correlation coefficient of 0.80-1.00 was considered excellent agreement; 0.60-0.79, good agreement; 0.40-0.59, moderate agreement; 0.20-0.39, weak agreement; and 0.00-0.19, no agreement. Normality tests (Kolmogorov-Smirnov test and Shapiro-Wilk test) were used to determine whether all measurement data were in accordance with a normal distribution. Preoperative and postoperative range of shoulder motion and clinical scores were compared by paired t tests. Postoperative outcome scores were compared between groups using analysis of variance and independent-samples t test. For the cuff integrity grade distribution on MRI and B-US, rank sum test was used for statistical analysis. All of the contrasts were considered significant when p < 0.05. The data were processed and analysed using the SPSS (IBM) v.25 program.