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.

Magnetic resonance imaging for relationship between the severity of perianchor fluid collection and rotator cuff integrity after arthroscopic double-row suture-bridge rotator cuff repair.

PURPOSE: The primary purpose of this study was to assess perianchor fluid collection (PFC) severity of medial anchor and rotator cuff integrity association after arthroscopic double-row suture-bridge rotator cuff repair (RCR) and the secondary purpose was to identify the demographic and radiologic risk factors for high-grade PFC. HYPOTHESIS: Re-tear rate would be significant higher in patients with high-grade PFC. METHODS: We retrospectively reviewed patients with arthroscopic double-row suture-bridge RCR for full-thickness rotator cuff tear (RCT) at our institution between February 2012 and May 2018. Based on the PFC severity, they were divided into the no-fluid (no fluid collection), low-grade (minimal or local fluid collection around the anchor), and high-grade (fluid collection beyond the entire length of the anchor) groups. Magnetic resonance imaging was performed 6 months postoperatively for assessing PFC severity and repaired rotator cuff integrity association, besides evaluating correlation between severity and various demographic and radiologic factors, including work level (low/medium/high) and RCT size. RESULTS: This study included 312 patients, 181 (58%) in the no fluid group, 82 (26.3%) in the low-grade PFC group, and 49 (15.7%) in the high-grade PFC group. Re-tear occurred in 73 (23.4%) patients and was more frequent in the high-grade group (26/49 [53.1%]) than in the no-fluid (27/181 [14.9%]; p<0.001) and low-grade (20/82 [24.4%]; p=0.001) groups, without statistically significant differences between the latter two (p=0.082). Among the demographic factors, work level (low/medium/high) differed significantly between the no-fluid (22.1%/58.0%/19.9%), low-grade (25.7%/46.3%/28.0%), and high-grade (26.5%/34.7%/38.8%) groups (p=0.026). Among the radiologic factors, the mediolateral tear size differed significantly between the three groups (no-fluid group: 1.7±0.8cm, low-grade group: 1.8±0.6cm, high-grade group: 2.2±1.0cm; p=0.003). Multivariate regression analysis showed that mediolateral tear size (odds ratio: 1.821; 95% confidence interval: 1.258-2.636; p=0.001) was an independent risk factor for high-grade PFC. CONCLUSIONS: After arthroscopic double-row suture-bridge RCR, the highest re-tear rate was observed in patients with high-grade PFC, while there was no significant difference in rates between no-fluid and low-grade PFC groups. As PFC severity increased, the risk of re-tear increased. In particular, larger mediolateral tear size was associated with high-grade PFC. LEVEL OF EVIDENCE: III; case-control 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.

Outcomes of arthroscopic single-row repair alone vs. repair with human dermal allograft patch augmentation in patients with large to massive, posterosuperior rotator cuff tears: a retrospective comparative study.

BACKGROUND: Large to massive rotator cuff tears (RCTs) affect shoulder functions profoundly with unmanageable disability without intervention. The retear rates with arthroscopic rotator cuff repair (ARCR) in these patients are abysmal. Patch augmentation has been credited for preventing retears, improving functions by increasing the strength, and acting as a bioconductive scaffold. This study aimed to assess the retear rates and compare the clinical and radiological outcomes between the ARCR with and without acellular human dermal allograft (HDA) augmentation. METHODS: This is a retrospective comparative study among patients diagnosed with large to massive, posterosuperior RCTs, operated between January 2020 and December 2021, including 36 patients (group I) with and 131 patients (group II) without HDA augmentation, with a mean follow-up of 20 (range, 12-35) months. The average age was 64 (range, 49-80) and 66 (range, 41-81) years in groups I and II, respectively. In group I, there were 16 male and 20 female patients, whereas in group II, there were 58 male and 73 female patients. RESULTS: The visual analog scale score improved to 1.1 ± 1.7 in group I and 2.1 ± 1.7 in group II (P = .005). There was a greater improvement in the University of California, Los Angeles shoulder score to 30.1 ± 4.2 in group I compared with 23.2 ± 3.9 in group II (P = .046). Forward flexion (degrees) improved from a mean of 103.2 ± 18.6 to 138.9 ± 23.5 in group I and from 106.4 ± 21.3 to 127.0 ± 19.5 in group II (P = .004). The acromiohumeral interval (mm) measured in anteroposterior radiographs increased to 8.4 ± 1.8 in group I and 8.2 ± 2.0 in group II (P = .006). The satisfaction after the procedure was 4.4 ± 0.6 in group I and 3.1 ± 1.1 in group II (P = .044). The retear rate in the HDA-augmented group was 5.6% as compared with 29.1% in the nonaugmented group, which was statistically significant (P = .007). There were no complications or adverse tissue reactions against HDA seen in any patients. CONCLUSION: In patients with large to massive, posterosuperior RCTs, patch augmentation with acellular HDA significantly averted the retears after ARCR without any graft-related complications. The augmentation also resulted in improved shoulder function and greater range of motion compared with the nonaugmented group.

Recombinant Human Parathyroid Hormone Biocomposite Promotes Bone-to-Tendon Interface Healing by Enhancing Tenogenesis, Chondrogenesis, and Osteogenesis in a Rabbit Model of Chronic Rotator Cuff Tears.

PURPOSE: To investigate the effect of recombinant human parathyroid hormone (rhPTH) biocomposite on bone-to-tendon interface (BTI) healing for surgical repair of a chronic rotator cuff tear (RCT) model of rabbit, focusing on genetic, histologic, biomechanical and micro-computed tomography (CT) evaluations. METHODS: Sixty-four rabbits were equally assigned to the 4 groups: saline injection (group A), nanofiber sheet alone (group B), rhPTH-soaked nanofiber sheet (nanofiber sheet was soaked with rhPTH, group C), and rhPTH biocomposite (rhPTH permeated the nanofiber sheet by coaxial electrospinning, group D). The release kinetics of rhPTH (groups C and D) was examined for 6 weeks in vitro. Nanofiber scaffolds were implanted on the surface of the repair site 6 weeks after the induction of chronic RCT. Genetic and histologic analyses were conducted 4 weeks after surgery. Furthermore, genetic, histologic, biomechanical, micro-CT, and serologic analyses were performed 12 weeks after surgery. RESULTS: In vivo, group D showed the highest collagen type I alpha 1 (COL1A1), collagen type III alpha 1 (COL3A1), and bone morphogenetic protein 2 (BMP-2) messenger RNA (mRNA) expression levels (all P < .001) 4 weeks after surgery; however, there were no differences between groups at 12 weeks postsurgery. After 12 weeks postsurgery, group D showed better collagen fiber continuity and orientation, denser collagen fibers, more mature bone-to-tendon junction, and greater fibrocartilage layer formation compared with the other groups (all P < .05). Furthermore, group D showed the highest load-to-failure rate (28.9 ± 2.0 N/kg for group A, 30.1 ± 3.3 N/kg for group B, 39.7 ± 2.7 N/kg for group C, and 48.2 ± 4.5 N/kg for group D, P < .001) and micro-CT outcomes, including bone and tissue mineral density, and bone volume/total volume rate (all P < .001) at 12 weeks postsurgery. CONCLUSIONS: In comparison to rhPTH-soaked nanofiber sheet and the other control groups, rhPTH biocomposite effectively accelerated BTI healing by enhancing the mRNA expression levels of COL1A1, COL3A1, and BMP-2 at an early stage and achieving tenogenesis, chondrogenesis, and osteogenesis at 12 weeks after surgical repair of a chronic RCT model of rabbit. CLINICAL RELEVANCE: The present study might be a transitional study to demonstrate the efficacy of rhPTH biocomposites on BTI healing for surgical repair of chronic RCTs as an adaptable polymer biomaterial in humans.

Arthroscopic transosseous anchorless rotator cuff repair reduces bone defects related to peri-implant cyst formation: a comparison with conventional suture anchors using propensity score matching.

BACKGROUND: The transosseous anchorless repair (ToR) technique was recently introduced to avoid suture anchor-related problems. While favorable outcomes of the ToR technique have been reported, no previous studies on peri-implant cyst formation with the ToR technique exist. Therefore, this study compared the clinical outcomes and prevalence of peri-implant cyst formation between the ToR technique and the conventional transosseous equivalent technique using suture anchors (SA). METHODS: Cases with arthroscopic rotator cuff repair (ARCR) between 2016 and 2018 treated with the double-row suture bridge technique were retrospectively reviewed. Patients were divided into ToR and SA groups. To compare clinical outcomes, 19 ToR and 57 SA cases without intraoperative implant failure were selected using propensity score matching (PSM). While intraoperative implant failure rate was analyzed before PSM, retear rate, peri-implant cyst formation rate, and functional outcomes were compared after PSM. RESULTS: The intraoperative implant failure rate (ToR, 8% vs. SA, 15.3%) and retear rate (ToR, 5.3% vs. SA, 19.3%) did not differ between the two groups (all P>0.05). However, peri-implant cysts were not observed in the ToR group, while they were observed in 16.7% of the SA group (P=0.008). Postoperative functional outcomes were not significantly different between the two groups (all P>0.05). CONCLUSIONS: The ToR technique produced comparable clinical outcomes to conventional techniques. Considering the prospect of potential additional surgeries, the absence of peri-implant cyst formation might be an advantage of ToR. Furthermore, ToR might reduce the medical costs related to suture anchors and, thereby, could be a useful option for ARCR. Level of evidence: III.

Anterior capsular reconstruction in irreparable subscapularis tear: human dermal allograft.

BACKGROUND: The irreparable subscapularis (SSc) tears pose an extremely difficult situation to manage, especially in the younger population. The anterior capsular reconstruction (ACR) with human dermal allograft (HDA) is an alternative to tendon transfer with sound biomechanical advantages and clinical outcomes. The purpose of this study was to evaluate the early clinical and radiologic outcomes of open ACR with HDA in patients with irreparable SSc tears. METHODS: Eighteen patients who had an open ACR with HDA for irreparable SSc tears between August 2020 and January 2022 were enrolled. There were 11 male and 7 female patients with a mean age of 63.7 years and a mean follow-up of 17 months (range, 12-28 months). The dominant side was affected in 10 patients. One of the 18 patients had reconstruction with single-layer HDA, 14 had double-layer HDA, and 3 had SSc augmentation over double-layer HDA. Clinical and radiologic outcomes were assessed and compared pre- and postoperatively. RESULTS: There was significant improvement in visual analog scale score from 6.6 ± 1.6 to 1.6 ± 1.5 (P < .001) and in the total University of California-Los Angeles shoulder score from 12.4 ± 4.3 to 29.0 ± 4.5 (P < .001). Forward flexion, abduction, and internal rotation (IR) increased by 28.6°, 32.5°, and 11.8°, respectively (P < .001). External rotation decreased by 6.4° (P = .020). There was notable improvement in IR strength (percentage of that of the opposite, normal side) from 66.0% ± 19.4% to 84.4% ± 22.3% (P = .008). The mean postoperative coracohumeral distance improved from 3.0 to 6.0 mm (P < .001), the anterior translation of the humeral head reduced from 1.5 to 0.5 mm (P = .210), and the acromiohumeral interval from 8.1 to 8.8 mm (P = .070). The patients' satisfaction at final follow-up was rated 4.1 of 5.0 (P < .001). Sixteen of 18 patients (88.9%) had the HDA healed at the glenoid and humeral side, and 2 (11.1%) had retear at the final follow-up. Among the 17 who had double-layer HDA, none showed any healing between the layers. CONCLUSION: This study showed that early significant and comprehensive improvement inclusive of pain relief, improvement in range of motion, IR strength, and reduction of anterosuperior translation was achievable by open ACR with HDA for irreparable SSc tear.

The correlation of the spinoglenoid ganglion cyst size with the electrophysiological alterations of suprascapular nerve and the rotator cuff muscle power.

BACKGROUND: Although various treatment options are available for spinoglenoid cyst, including conservative and surgical methods, there is no standard guideline for its surgical decompression. Thus, the purpose of the study was to correlate the size of the spinoglenoid notch ganglion cyst (GC) as revealed by magnetic resonance imaging (MRI) with electrophysiological alterations, muscle power, and pain severity, and to estimate a cut-off value of cyst size to perform a decompression. METHODS: Between January 2010 and January 2018, the patients with a GC at the spinoglenoid notch diagnosed on MRI, and who had a minimum follow-up of 2 years after the decompression were included. Maximum cyst diameter as measured on MRI was used for comparison. Electromyography (EMG) and nerve conduction velocity (NCV) studies were performed before the surgery. Peak torque deficit (PTD) percentage compared to opposite shoulder was calculated preoperatively and at 1 year after surgery. Pain severity was estimated using visual analogue scale (VAS) preoperatively. RESULTS: Ten (50%) of 20 patients with GC > 2.2 cm and 1 (5.9%) of 17 patients with GC < 2.2 cm showed EMG/NCV abnormalities (p = 0.019). There was a correlation between the cyst size and the positive EMG/NCV findings (Correlation coefficient (CC) = 0.535, p < 0.001). The preoperative peak torque deficit on the external rotation was correlated with the positive EMG/NCV findings (CC = 0.373, p = 0.021). The PTD was improved significantly at 1 year postoperatively in patients with a GC size >2.2 cm (p = 0.029). The cyst size was not related to the preoperative pain VAS and muscle power. CONCLUSIONS: The spinoglenoid cyst size >2.2 cm, but not pain severity or muscle power, correlates with the positive finding of EMG for compressive suprascapular neuropathy. The GC size >2.2 cm can be a reference to decide the need of decompression surgery. LEVEL OF EVIDENCE: IV, case series.

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.

Subacromial notching after reverse total shoulder arthroplasty.

BACKGROUND: Scapular notching is a well-known postoperative complication of reverse total shoulder arthroplasty (RTSA). However, subacromial notching (SaN), a subacromial erosion caused by repeated abduction impingement after RTSA, has not been previously reported in a clinical setting. Therefore, this study aimed to assess the risk factors and functional outcomes of SaN after RTSA. METHODS: We retrospectively reviewed the medical records of 125 patients who underwent RTSA with the same design between March 2014 and May 2017 and had at least 2 years of follow-up. SaN was defined as subacromial erosion observed at the final follow-up but not on the X-ray 3 months after surgery. Radiologic parameters representing the patient's native anatomy and degrees of lateralization and/or distalization during surgery were evaluated using preoperative and 3 months postoperative X-rays. The visual analogue scale of pain, active range of motion, and American Shoulder and Elbow Surgeons score were assessed preoperatively and at the final follow-up to evaluate the functional outcomes of SaN. RESULTS: SaN occurred in 12.8% (16/125) of enrolled patients during the study period. Preoperative center of rotation-acromion distance (P = .009) and postoperative humerus lateralization offset, which evaluated the degree of lateralization after RTSA (P = .003), were risk factors for SaN. The preoperative center of rotation-acromion distance and postoperative humerus lateralization cutoff values were 14.0 mm and 19.0 mm, respectively. The visual analogue scale of pain (P = .01) and American Shoulder and Elbow Surgeons score (P = .04) at the final follow-up were significantly worse in patients with SaN. CONCLUSIONS: SaN might adversely affect postoperative clinical outcomes. As SaN correlated with patients' anatomical characteristics and degree of lateralization during RTSA, the implant's degree of lateralization should be adjusted according to the patient's own anatomical characteristics.

Serum Vitamin D Level Correlations With Tissue Vitamin D Level and Muscle Performance Before and After Rotator Cuff Repair.

BACKGROUND: There is a lack of studies about serum and tissue vitamin D levels of the rotator cuff muscle on muscle power, fatty degeneration, and healing failure after rotator cuff repair (RCR). Furthermore, no studies have evaluated vitamin D receptor proteins in the rotator cuff that show a close association with serum vitamin D levels. PURPOSE: To evaluate the correlations between serum vitamin D and tissue vitamin D as well as perioperative variables of arthroscopic RCR. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: From March 2017 to October 2017, a total of 36 patients who underwent RCR were prospectively enrolled, and supraspinatus muscle tissue was obtained during surgery to analyze tissue vitamin D levels. Serum vitamin D levels were checked preoperatively and at 6 months and 1 year postoperatively. Tissue vitamin D levels were assessed using liquid chromatography, and the vitamin D receptor was measured by western blotting. Isokinetic muscle performance test (IMPT; peak torque and torque deficiency compared with the opposite shoulder) results and fatty degeneration of the rotator cuff using the Goutallier classification were assessed preoperatively and at 1 year after surgery. The American Shoulder and Elbow Surgeons score and Constant score were collected at 2 years after surgery. Healing failure of the repaired rotator cuff was analyzed by magnetic resonance imaging at 1 year after surgery. RESULTS: Overall, only three patients (8.3%) had serum vitamin D sufficiency (>20 ng/mL). Among 36 patients, 26 patients returned for their 1-year follow-up. Lower preoperative serum vitamin D levels resulted in lower serum vitamin D levels at 6 months and 1 year postoperatively (all P < .05). Lower preoperative and 1-year postoperative serum vitamin D levels resulted in more torque deficiency on the IMPT in abduction than higher preoperative and 1-year postoperative serum vitamin D levels (all P < .05). Tissue vitamin D levels had a strong correlation with preoperative serum vitamin D levels (P = .001). Lower tissue vitamin D levels were associated with lower peak torque on the IMPT in abduction (P = .043) and a tendency of lower peak torque on the IMPT in external rotation (P = .077) at 1 year postoperatively. There was no correlation between tissue and serum vitamin D levels and functional outcomes, fatty degeneration, and healing failure after surgery (all P > .05). The vitamin D receptor showed no correlation with any variables (all P > .05). CONCLUSION: Lower preoperative serum vitamin D levels had a strong correlation with lower tissue vitamin D levels and lower serum vitamin D levels at 1 year after surgery. Furthermore, the patients with lower serum vitamin D levels showed more weakness of muscle power perioperatively. The results of this study emphasized the association between vitamin D levels and rotator cuff muscle power.

Synovial Osteochondromatosis: Clinical Characteristics Unique to the Shoulder.

Background: Synovial osteochondromatosis (SOC) of the shoulder is a rare condition with unclear characteristics. This study evaluated the clinical features and postoperative functional outcomes of SOC of the shoulder that are distinct from SOC of other joints. Methods: The characteristics of 28 shoulders with SOC that underwent arthroscopy were retrospectively assessed. Ten shoulders (35.7%) had rotator cuff tears (RCTs) and underwent concomitant arthroscopic rotator cuff repair. The mean follow-up period was 83.6 months (range, 24-154 months). Demographic characteristics and loose bodies localized under arthroscopy were compared between cases with and without concomitant RCTs. Radiography, ultrasonography, or magnetic resonance imaging were performed preoperatively and postoperatively. Visual analog scale (VAS) scores for pain and satisfaction were evaluated for all cases, and functional scores were assessed in shoulders with concomitant RCTs. Results: The average age was 36.2 ± 15.6 years among patients without RCTs and 58.3 ± 7.2 years among patients with RCTs. Seven shoulders (7%) had osteoarthritis. Arthroscopy revealed loose bodies in multiple spaces, including the glenohumeral joint, subacromial (SA) space, and biceps tendon sheath. Overall, loose bodies were found in multiple spaces in 12 shoulders (42.9%). Loose bodies were found in the SA space only in 4 shoulders (22.2%) without RCTs and in 7 shoulders (70.0%) with RCTs. VAS for pain decreased significantly from 3.9 ± 2.3 to 1.1 ± 1.3 (p < 0.001). The functional scores increased significantly after arthroscopic management for patients with concurrent RCTs (all p < 0.05). Recurrence of SOC occurred in 3 of the 22 shoulders (13.6%) who underwent postoperative imaging, but no patient had a recurrent RCT. Conclusions: Pain relief and patient satisfaction were achieved via arthroscopic management. Unlike in other joints, loose bodies can occur simultaneously in several spaces in the shoulder, including the glenohumeral joint, SA space, and biceps tendon sheath. Early diagnosis of SOC of the SA space can help prevent osteoarthritis and RCT progression.

Long-term outcomes after humeral head replacement and total shoulder replacement for osteonecrosis of the humeral head: a mean follow-up of 8 years.

INTRODUCTION: The purpose of this study was to compare the outcomes and complications after humeral head replacement (HHR) and total shoulder replacement (TSR) in patients with osteonecrosis of the humeral head (ONHH). MATERIALS AND METHODS: Twenty-six patients who underwent shoulder replacement (13 HHRs and 13 TSRs) for nontraumatic ONHH were included. The mean follow-up period was 96.4 months. The visual analog scale (VAS) pain score, the University of California at Los Angeles (UCLA) score, the American Shoulder and Elbow Surgeon (ASES) score, and range of motion (ROM) at the final follow-up evaluation were used for the assessment of clinical outcomes. RESULTS: The mean VAS pain score, UCLA score, and ASES score showed significant improvement from 6.3, 11.6, and 35.0 before surgery to 2.2, 28.9, and 82.6 at the final follow-up evaluation (all p < 0.001). No significant differences regarding all clinical scores and ROMs were observed between the HHR group and the TSR group, except that a greater abduction angle was observed in the HHR group compared with the TSR group (123.1° versus 96.9°, p = 0.014). Two patients in the TSR group underwent multiple reoperations due to periprosthetic joint infection. No revision surgeries were performed for glenoid erosion following HHR or aseptic glenoid loosening following TSR. CONCLUSIONS: The findings of this study showed satisfactory clinical and radiological outcomes with implant longevity for both HHR and TSR in patients with nontraumatic ONHH. The HHR group had a greater abduction angle compared with the TSR group.

Increased HbA1c Levels in Diabetics During the Postoperative 3-6 Months After Rotator Cuff Repair Correlated With Increased Retear Rates.

PURPOSE: To evaluate whether glycemic control affects the integrity of the repaired rotator cuff during the postoperative healing period after arthroscopic double-row suture bridge rotator cuff repair (RCR) METHODS: We retrospectively reviewed patients with diabetes mellitus (DM) who underwent arthroscopic double-row suture bridge RCR at our institution between March 2016 and November 2019. We included the patients who evaluated for serum glycosylated hemoglobin (HbA1c) levels within 1 month before and 3-6 months after surgery. Magnetic resonance imaging was conducted 6 months after surgery to evaluate the integrity of the repaired cuff tendon. Patients were categorized into two groups based on comparison between preoperative and postoperative HbA1c values: Group I (increased postoperative HbA1c) and Group D (same or decreased postoperative HbA1c). The correlation between preoperative/postoperative HbA1c, HbA1c increase/same or decrease (during the healing period), and post-RCR integrity was evaluated, including various demographic and radiologic factors. RESULTS: A total of 103 patients were analyzed, group I was 47, and group D was 56, respectively. The retear rate of 51.1% (24/47) in Group I was significantly higher than 14.3% (8/56) in Group D (P < .001). HbA1c levels measured 3-6 months after surgery (mean: 6.9; 95% CI: 6.6-7.3 vs mean: 6.5; 95% CI: 6.3-6.7, P = .034), and the proportion of group I and group D were significantly different (75%/25% vs 32.4%/67.6%, P < .001) between the retear and healing groups. Multivariable logistic regression analysis identified increased HbA1c as an independent risk factor for retear (odds ratio: 5.402; 95% CI: 2.072-14.086; P < .001). CONCLUSIONS: The glycemic control within 3-6 months after surgery when the healing process of the tendon was in progress had a significant effect on retear rate. In particular, the retear rate was higher when the HbA1c level increased at postoperative 3-6 months compared to before surgery. LEVEL OF EVIDENCE: Retrospective case-control comparative study, Level III.

Anteroposterior and Lateral Coverage of the Acromion: Prediction of the Rotator Cuff Tear and Tear Size.

Background: The aim of this study was to assess whether the anteroposterior coverage of the acromion reflecting acromial morphology affects the rotator cuff tear (RCT) and tear size, in addition to the lateral coverage. Methods: Medical records of 356 patients with RCTs, concentric osteoarthritis, and calcific tendinitis identified using three-dimensional computed tomography between January 2016 and December 2017 were retrospectively analyzed. The patients were divided into group A (those with RCTs) and group B (those with concentric osteoarthritis or calcific tendinitis). Subsequently, group A was subdivided into three categories according to the size of RCTs: small-to-medium, large, and massive. The lateral coverage was measured through the lateral acromial angle (LAA) and critical shoulder angle (CSA), whereas the anteroposterior coverage was measured via the acromial tilt (AT), acromiohumeral interval (AHI) in the sagittal view, and anteroposterior coverage index (APCI) as a new radiologic parameter. Results: Between groups A and B, CSA (34.5° ± 3.4° and 30.8° ± 3.4°, respectively), APCI (0.83 ± 0.10 and 0.75 ± 0.08, respectively), and AHI (6.3 ± 2.0 mm and 7.8 ± 1.8 mm, respectively) were significantly different (all p < 0.001), whereas LAA and AT did not show a significant difference between the groups (p = 0.089 and p = 0.665, respectively). The independent predictive radiologic parameters of the RCT were the CSA, APCI, and AHI (p < 0.001, p < 0.001, and p = 0.043, respectively); among these, the APCI showed the highest regression coefficient (odds ratio = 2.82). The parameters associated with the size of RCTs were CSA (p = 0.022) and AHI, of which AHI, in particular, had the most significant effect on both small-to-medium and large tears (all p < 0.001). Conclusions: Large CSA, high APCI, and low AHI were predictors of RCTs, with the APCI showing the strongest correlation. In addition to the large CSA, low AHI also correlated with the size of RCTs and affected the entire size groups. We suggest that both the lateral coverage and anteroposterior coverage of the acromion should be considered essential factors for predicting the presence of RCTs and tear size.

The scissors sign: a provocative test for detecting the leading-edge tear of subscapularis tendon: a diagnostic study.

BACKGROUND: Several physical examination tests and signs have been described to aid in the diagnosis of subscapularis (SSC) tear, but have limitations and variable sensitivity. This study aimed to introduce a novel test for detecting a leading-edge tear of the subscapularis (LETS), the most important tendinous portion of SSC. METHODS: A total of 233 patients who underwent arthroscopic repair for anterior and superior cuff tears between January 2018 to September 2019 were retrospectively reviewed. The provocative test we have coined as the "scissors sign" and the other related clinical tests (i.e., belly press, belly off, Napoleon, lift off, internal rotation lag, bear hug tests) were performed preoperatively. Whether the patient has a LETS or the complete tear of the SSC (CTS) was confirmed by arthroscopic findings. Sensitivity, specificity, and areas under the receiver operating characteristic curve were calculated for each test. RESULTS: In patients who had LETS with or without supraspinatus tear, the scissors sign showed the highest sensitivity (91.4%) with a specificity of 81.6%, positive predictive value (PPV) of 80.2%, and negative predictive value (NPV) of 92.1%. In patients with isolated LETS, the scissors sign also showed the highest sensitivity (90.3%) with a specificity of 81.6%, PPV of 57.1%, and NPV of 96.8%. The scissors sign for the complete tear of the subscapularis (CTS) with or without supraspinatus tear and the isolated CTS had a sensitivity of 73.1 and 75%, respectively. CONCLUSIONS: The scissors sign is a novel provocative test that can be helpful in the diagnosis of subscapularis tears, especially LETS, with its high sensitivity and diagnostic accuracy. In combination with other tests, the scissors sign will be a good screening tool.

Perianchor cyst formation in all-suture anchor after rotator cuff repair: an evaluation of anchor insertion angle.

BACKGROUND: Previous studies reported that micromotion after all-suture anchor implantation can lead to perianchor cyst formation (PCF), leading to risk of retear. Modifying anchor insertion angle (AIA) is known to be one of the various ways to increase anchor stability. However, there currently are few studies that assess the correlation between PCF, AIA, and retear. PURPOSE: To find the correlation of PCF and the repaired rotator cuff integrity with AIA after arthroscopic double-row suture-bridge rotator cuff repair (RCR) using an all-suture anchor in the medial row. METHODS: A total of 218 patients who underwent arthroscopic double-row suture-bridge RCR were retrospectively reviewed. All patients underwent RCR using all-suture anchors and polyether ketone anchors in the medial and lateral rows, respectively. Magnetic resonance imaging was conducted 6 months after the surgery to evaluate PCF, AIA, and integrity of the repaired cuff. The all-suture anchor insertion angle in the medial row was measured with reference to the greater tuberosity to assess the relationship between the AIA and PCF. The correlations between PCF, AIA, and post-RCR integrity were evaluated including various demographic and radiologic factors. RESULTS: Perianchor cysts were formed in 93 patients (42.7%). Mediolateral tear size (2.1 ± 1.2 cm vs. 1.7 ± 0.9 cm, P = .034) and AIA (61.9° ± 15.2° vs. 68.4° ± 13.0°, P = .001) were significantly different between patient groups with and without perianchor cysts. Multivariate logistic regression analysis showed that mediolateral tear size (odds ratio [OR] 1.318, 95% confidence interval [CI] 1.008-1.724; P = .043) and AIA (OR 0.967, 95% CI 0.947-0.988; P = .002) were independent risk factors for PCF. In addition, PCF was observed more frequently (69.6% vs. 32.1%, P < .001) and the AIA was lower (59.4° ± 13.7° vs. 67.8° ± 13.8°, P < .001) in the retear group than in the healed group. CONCLUSIONS: Perianchor cysts were formed in approximately 40% of patients who underwent arthroscopic double-row suture-bridge RCR using all-suture anchors. Low AIA and large mediolateral tear size were risk factors for PCF. Moreover, perianchor cyst and AIA were correlated with post-RCR integrity. Therefore, a high AIA must be carefully considered when all-suture anchors are inserted into the medial row when performing RCR.

Three-dimensionally printed recombinant human parathyroid hormone-soaked nanofiber sheet accelerates tendon-to-bone healing in a rabbit model of chronic rotator cuff tear.

BACKGROUND: Recombinant human parathyroid hormone (rhPTH) promotes tendon-to-bone healing in humans and animals with rotator cuff tear (RCT). However, problems regarding repeated systemic rhPTH injections in humans exist. This study was conducted to evaluate the effect of topical rhPTH administration using 3-dimensionally (3D) printed nanofiber sheets on tendon-to-bone healing in a rabbit RCT model compared to that of direct topical rhPTH administration. METHODS: Eighty rabbits were randomly assigned to 5 groups (n = 16 each). To create the chronic RCT model, we induced complete supraspinatus tendon tears in both shoulders and left them untreated for 6 weeks. All transected tendons were repaired in a transosseous manner with saline injection in group A, hyaluronic acid (HA) injection in group B, 3D-printed nanofiber sheet fixation in group C, rhPTH and HA injection in group D, and 3D-printed rhPTH- and HA-soaked nanofiber sheet fixation in group E. Genetic (messenger RNA expression evaluation) and histologic evaluations (hematoxylin and eosin and Masson trichrome staining) were performed in half of the rabbits at 4 weeks postrepair. Genetic, histologic, and biomechanical evaluations (mode of tear and load to failure) were performed in the remaining rabbits at 12 weeks. RESULTS: For genetic evaluation, group E showed a higher collagen type I alpha 1 expression level than did the other groups (P = .008) at 4 weeks. However, its expression level was downregulated, and there was no difference at 12 weeks. For histologic evaluation, group E showed greater collagen fiber continuity, denser collagen fibers, and more mature tendon-to-bone junction than did the other groups (P = .001, P = .001, and P = .003, respectively) at 12 weeks. For biomechanical evaluation, group E showed a higher load-to-failure rate than did the other groups (P < .001) at 12 weeks. CONCLUSION: Three-dimensionally printed rhPTH-soaked nanofiber sheet fixation can promote tendon-to-bone healing of chronic RCT.

Retear After Arthroscopic Rotator Cuff Repair Results in Functional Outcome Deterioration Over Time.

PURPOSE: This study aimed to evaluate the effect of retear on long-term functional outcomes and glenohumeral joint osteoarthritis (OA) progression after arthroscopic rotator cuff repair (ASRCR). METHODS: We retrospectively reviewed 201 patients who underwent ASRCR and were followed up for at least 5 years. Rotator cuff tendon structural integrity was evaluated using magnetic resonance imaging and/or ultrasonography. Pain, active range of motion, and the American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) were evaluated for functional outcomes. To evaluate deterioration over time, the minimal clinically important difference value of pain and ASES were used. RESULTS: The mean follow-up period was 8.6 ± 2.2 years and overall retear rate was 21.4%. OA progression was strongly associated with retear (odds ratio 5.1, P < .001). Functional outcomes at the 2-year postoperative follow-up significantly improved compared to the preoperative status (all P < .017), regardless of retear. However, the retear group presented worse functional outcomes at the final follow-up (pain: 3.1 ± 2.6; ASES: 72.0 ± 17.4) than at the 2-year postoperative follow-up (pain: 1.2 ± 2.3, P = .014; ASES: 91.1 ± 9.9, P= .015) than the healed tendon group at final follow-up (pain: .6 ± 1.7; P < .001; ASES 95.5 ± 11.8; P < .001). The time for deterioration of pain (healed group vs. retear group: 5.5 ± 0.5 vs. 10.6 ± 0.4 years; P < .001) and ASES (healed group vs. retear group: 7.5 ± 0.5 vs. 12.8 ± 0.2 years; P < .001) decreased in the retear group. CONCLUSIONS: The functional status improved after ASRCR in short- and long-term follow-up, regardless of retear. However, retear was strongly associated with OA progression, and long-term functional outcomes deteriorated over time in retear cases, which was not observed during short-term follow-up. STUDY DESIGN: III, retrospective cohort study.

Allogeneic Dermal Fibroblasts Improve Tendon-to-Bone Healing in a Rabbit Model of Chronic Rotator Cuff Tear Compared With Platelet-Rich Plasma.

PURPOSE: To compare the effects of allogeneic dermal fibroblasts (ADFs) and platelet-rich plasma (PRP) on tendon-to-bone healing in a rabbit model of chronic rotator cuff tear. METHODS: Thirty-two rabbits were divided into 4 groups (8 per group). In 2 groups, the supraspinatus tendon was detached and was left as such for 6 weeks. At 6 weeks after creating the tear model, we performed transosseous repair with 5 × 106 ADFs plus fibrin injection in the left shoulder and PRP plus fibrin in the right shoulder. The relative expression of the COL1, COL3, BMP2, SCX, SOX9, and ACAN genes was assessed at 4 weeks (group A) and 12 weeks (group B) after repair. Histologic and biomechanical evaluations of tendon-to-bone healing at 12 weeks were performed with ADF injection in both shoulders in group C and PRP injection in group D. RESULTS: At 4 weeks, COL1 and BMP2 messenger RNA expression was higher in ADF-injected shoulders (1.6 ± 0.8 and 1.0 ± 0.3, respectively) than in PRP-injected shoulders (1.0 ± 0.3 and 0.6 ± 0.3, respectively) (P = .019 and P = .013, respectively); there were no differences in all genes in ADF- and PRP-injected shoulders at 12 weeks (P > .05). Collagen continuity, orientation, and maturation of the tendon-to-bone interface were better in group C than in group D (P = .024, P = .012, and P = .013, respectively) at 12 weeks, and mean load to failure was 37.4 ± 6.2 N/kg and 24.4 ± 5.2 N/kg in group C and group D, respectively (P = .015). CONCLUSIONS: ADFs caused higher COL1 and BMP2 expression than PRP at 4 weeks and showed better histologic and biomechanical findings at 12 weeks after rotator cuff repair of the rabbit model. ADFs enhanced healing better than PRP in the rabbit model. CLINICAL RELEVANCE: This study could serve as a transitional study to show the effectiveness of ADFs in achieving tendon-to-bone healing after repair of chronic rotator cuff tears in humans.