Subscapularis Repair in Reverse Total Shoulder Arthroplasty: Differences in Outcomes Based on Preoperative Quality of Subscapularis Tendon.

Purpose: This study examines the influence of preoperative fatty infiltration (FI) of the subscapularis tendon (SBS) on outcomes following reverse total shoulder arthroplasty (rTSA) with SBS repair. Methods: A cohort of 161 rTSA patients with SBS repair, followed for a mean of 45.3 months, was divided into three groups based on FI: Group A (intact upper and lower portions, n = 85), Group B (intact lower portions, n = 44), and Group C (fatty infiltrated in both portions, n = 32). The mean age was 74.5 years (range: 65-95). Results: Preoperative FI displayed significant disparity among the groups: Group A (1.18 ± 0.60), Group B (2.95 ± 0.56), and Group C (4.0 ± 0.00) (p < .001). Group A exhibited a more positive trend in activities of daily living, particularly in toileting ability (81% in Group A, 68% in Group B, and 72% in Group C), although without statistical significance (p = 0.220). Complication rates varied: Group A had seven acromial fractures (8%), three cases of instability (3%), and six instances of scapular notching (7%). Group B experienced four acromial fractures (9%) and four cases of scapular notching (9%), while Group C had only one case of scapular notching (3%) (p = 0.733). Conclusion: In cases characterized by favorable preoperative SBS quality, there was an elevation in functional internal rotation (IR) post-surgery, accompanied by an increased incidence of postoperative complications. Hence, careful consideration is advised when determining the necessity for SBS repair. Level of Evidence: Level III, retrospective comparative study.

Does timing influence rehabilitation outcomes in arthroscopic rotator cuff repair with biceps rerouting? a prospective randomized study.

BACKGROUND: Arthroscopic rotator cuff repair with biceps rerouting (ABR) has emerged as a reliable option for treating large posterosuperior rotator cuff tears (RCTs). This study aims to compare functional and structural outcomes of early vs. delayed motion rehabilitation protocols following ABR. METHODS: A total of 101 patients with semirigid, large, posterosuperior RCTs undergoing ABR were randomized into 2 groups: group I (early motion) with 53 patients (34 females, 19 males) and group II (delayed motion) with 48 patients (31 females, 17 males). In group I, the mean age was 63.9 years (range, 46-79), and in group II, it was 65.4 years (range, 43-78). The mean follow-up periods for group I and group II were 16.2 and 15.5 months, respectively. Preoperative and postoperative assessments were conducted at 3, 6, and 12 months, with structural integrity assessed with magnetic resonance imaging at a minimum follow-up of 12 months. Statistical analyses were performed to compare outcomes between the 2 groups. RESULTS: Both groups demonstrated significant improvements in visual analog scale score (group I: 4.0-1.6, group II: 3.7-1.4, P = .501), University of California-Los Angeles shoulder score (group I: 21.5-31.4, group II: 22.4-30.6, P = .331), and acromiohumeral interval (group I: 8.2 mm-9.1 mm, group II: 8.6 mm-9.5 mm, P = .412), with no statistically or clinically meaningful differences. Active range of movements (ROM) were not significantly different between groups, except for active forward flexion at 3 months (group I: 140.1°, group II: 119.2°, P = .006), that was not shown to be translated clinically into differences in function or healing between the groups in this study. Notably, retear rates were similar between groups (group I: 22.6%, group II: 20.8%, P = .826). CONCLUSION: This study's findings reveal no clinically discernible differences in active range of motion at 1-year follow-up between patients who underwent ABR for semirigid, large, posterosuperior RCTs and were assigned to either early or delayed motion protocols. Notably, the early motion group demonstrated a plateau in maximum range of movement improvement as early as 3 months postsurgery. Based on these results, implementing an early motion protocol is recommended as an effective approach in the postoperative rehabilitation following ABR.

Posterior Compression Test: a Provocative Test for Detecting Posterior Labral Tears.

Purpose: The purpose is to assess the diagnostic accuracy of a provocative test coined as the 'posterior compression test' (PCT) in those with the suspected posterior labral tear or lesion. Methods: A total of 515 'arthroscopic labral repairs' were identified between April 2013 and September 2020. Excluding those with concomitant shoulder pathologies, and only including those with pre-operative documentation of the PCT and/or the Jerk test, 191 patients were included. For the purposes of the analyses, the patients were divided into 'non-posterior' labral tear group which included the anterior labral tears and/or the superior labral anterior-to-posterior (SLAP) tears, versus 'any posterior' labral tear group which included the isolated posterior labral tears, the SLAP tears with posterior extension and the pan-labral tears. Results: When the PCT was performed for the isolated posterior labral tears, the sensitivity was 92.6% with the specificity of 86.5%. The positive predictive value and negative predictive value were 71.4-97%, respectively. The Jerk test's sensitivity was 77.8% but when the two tests were combined, the sensitivity increased up to 96.3%. The combined sensitivity with the Jerk test was still up to 94.6% with the AUC (area under curve) /ROC (receiver operator characteristic) at 0.855. Low 'false-positive' rate with the PCT was observed when the test was performed for the 'non-posterior' labral group, with the sensitivity of 13.5%. Conclusions: The posterior compression test correlated well with the arthroscopic diagnoses in a subset of patients with suspected posterior labral pathology, possibly by means of direct stimulation. Level of Evidence: III; Diagnostic Study.

Rotator cuff repairs with all-suture tape anchors: no difference in outcomes between with or without all-suture tape anchors.

PURPOSE: This study aimed at comparing the outcomes of medium- to large-sized rotator cuff repairs performed using the suture bridge technique either with or without tape-like sutures, and single row techniques with conventional sutures. METHODS: A total of 135 eligible patients with medium to large rotator cuff tears were identified and analyzed retrospectively, from 2017 to 2019. Only repairs using all-suture anchors were included in the study. Patients were divided into the following three groups: single-row (SR) repair (N = 50), standard double-row suture bridge (DRSB) repair with conventional sutures (N = 35), and DRSB with tape-like sutures (N = 50). The average postoperative follow-up period was 26.3 ± 9.8 months (range, 18-37). RESULTS: DRSB with tapes had the highest re-tear rate of 16% (8/50), but there was no significant difference with the re-tear rates observed in SR (8%, 4/50) and DRSB with conventional sutures (11.4%, 4/35) (n.s.). DRSB with tapes demonstrated higher rate of type 2 re-tears (10%) compared to type 1 re-tears (6%), but the other two groups showed either similar or higher rates of type 1 re-tears compared to that of type 2. Post-operative functional scores of the three groups improved significantly (all p < 0.05), but the differences between the groups were not statistically significant. CONCLUSIONS: No clinical difference in functional outcomes and re-tear rates were observed in DRSB with tapes when compared with SR and DRSB using the conventional sutures. Tape-like DRSB suture which was expected to be superior by its biomechanical advantage was clinically non-superior to conventional DRSB suture. There were no significant differences in VAS scores and UCLA scores. LEVEL OF EVIDENCE: Level III.

Functional Test Scales for Evaluating Cell-Based Therapies in Animal Models of Spinal Cord Injury.

Recently, spinal cord researchers have focused on multifaceted approaches for the treatment of spinal cord injury (SCI). However, as there is no cure for the deficits produced by SCI, various therapeutic strategies have been examined using animal models. Due to the lack of standardized functional assessment tools for use in such models, it is important to choose a suitable animal model and precise behavioral test when evaluating the efficacy of potential SCI treatments. In the present review, we discuss recent evidence regarding functional recovery in various animal models of SCI, summarize the representative models currently used, evaluate recent cell-based therapeutic approaches, and aim to identify the most precise and appropriate scales for functional assessment in such research.

Focused low-intensity pulsed ultrasound enhances bone regeneration in rat calvarial bone defect through enhancement of cell proliferation.

A number of studies have reported the therapeutic potential of low-intensity pulsed ultrasound (LIPUS) for induction of bone repair. This study investigated whether bone regeneration might be enhanced by application of focused LIPUS to selectively stimulate fractured calvarial bone. To accomplish this, bone defects were surgically created in the middle of the skull of rats that were subsequently exposed to focused LIPUS. Bone regeneration was assessed by repeated computed tomography imaging after the operation, as well as histologic analysis with calcein, hematoxylin and eosin and proliferating cell nuclear antigen assay. At 6 wk after surgery, bone formation in the focused LIPUS-treated group improved significantly relative to the control. Interestingly, new bone tissue sprouted from focused LIPUS target points. Histologic analysis after exposure to focused LIPUS revealed that proliferating cells were significantly increased relative to the control. Taken together, these results suggest that focused LIPUS can improve re-ossification through enhancement of cell proliferation in calvarial defect sites.

Nicotinamide exerts antioxidative effects on senescent cells.

Nicotinamide (NAM) has been shown to suppress reactive oxygen species (ROS) production in primary human fibroblasts, thereby extending their replicative lifespan when added to the medium during long-term cultivation. Based on this finding, NAM is hypothesized to affect cellular senescence progression by keeping ROS accumulation low. In the current study, we asked whether NAM is indeed able to reduce ROS levels and senescence phenotypes in cells undergoing senescence progression and those already in senescence. We employed two different cellular models: MCF-7 cells undergoing senescence progression and human fibroblasts in a state of replicative senescence. In both models, NAM treatment substantially decreased ROS levels. In addition, NAM attenuated the expression of the assessed senescence phenotypes, excluding irreversible growth arrest. N-acetyl cysteine, a potent ROS scavenger, did not have comparable effects in the tested cell types. These data show that NAM has potent antioxidative as well as anti-senescent effects. Moreover, these findings suggest that NAM can reduce cellular deterioration caused by oxidative damage in postmitotic cells in vivo.