Acquired Acromion Compromise, Including Thinning and Fragmentation, Is Not Associated With Poor Outcomes After Reverse Shoulder Arthroplasty.

BACKGROUND: Acquired acromial compromise, including thinning (less than 30% of the normal acromion) or fragmentation resulting from acromiohumeral impingement or previous acromioplasty, is a concern in reverse shoulder arthroplasty (RSA). This condition may lead to shoulder pain and difficulties in arm elevation because of acromial insufficiency fracture. QUESTIONS/PURPOSES: (1) Do patients with acromial compromise (thinning less than 30% of normal acromion or fragmentation) have worse functional outcome scores, ROM, and strength after RSA compared with patients without acromial compromise? (2) Are patients with acromial compromise at a higher risk of complications such as acromial insufficiency fracture after RSA? (3) Do patients who develop acromial insufficiency fracture have predisposing associated factors and worse clinical outcomes? METHODS: Between January 1, 2016, and December 31, 2020, we treated 398 patients with RSA, and all patients were considered potentially eligible for this study. Our clinic is part of the orthopaedic department within a tertiary general hospital, serving patients from across the country. Among them, 49% (197 of 398) of patients were excluded for the following reasons: 8% (31 of 398) because of proximal humerus fracture, 5% (19 of 398) because of osteonecrosis, 9% (35 of 398) because of previous infective arthritis, 5% (18 of 398) because of a deformed shoulder, 4% (14 of 398) because of poor general condition after surgery, 3% (12 of 398) because of death, and another 17% (68 of 398) were lost before the minimum study follow-up, leaving 51% (201 of 398) for analysis. A preoperative acromial compromise was defined as follows: (1) thinning of the acromion (< 3 mm), which means a thickness of less than 30% of the normal acromion thickness (8 to 9 mm), and (2) acromial fragmentation. Acromial thickness was measured using a CT scan. The middle portion of the anterolateral acromion, situated lateral to the distal end of the clavicle, was crosschecked using the axial view. Measurements were subsequently performed from both coronal and sagittal views. In all, 29 patients with acromion compromise and 172 without acromion compromise met the inclusion and exclusion criteria. There was no differential loss to follow-up before 2 years between patients with and without acromial compromise in this study (36% [16 of 45] versus 23% [52 of 224]; p = 0.12). We matched patients using propensity score, pairing them in a 1:3 ratio based on gender, age, bone mineral density, diagnosis, previous rotator cuff repair surgery, subscapularis repair or latissimus dorsi transfer performed during surgery, the type of prosthesis used, and follow-up duration. Twenty-three patients with acromial compromise (acromion compromised group) and 69 patients without acromial compromise (normal control group) were matched; the mean ± SD duration of follow-up was 40 ± 22 months in those with acromial compromise and 43 ± 19 months the in normal control group. Pre- and postoperative functional outcome scores, ROM, and shoulder strength were compared. Shoulder scaption refers to lifting the arm in the scapular plane, and scaption strength was measured by applying upward force with the arm at 90° while seated, pushing it as far as possible and measured using a handheld myometer. Complications, including acromial insufficiency fracture, scapular notching, dislocation, periprosthetic infection, and overall risk of complication, were analyzed. Acromial insufficiency fracture was diagnosed based on clinical and radiological findings. Clinically, sudden pain and tenderness at the acromion along with reduced shoulder elevation raised acromial insufficiency fracture suspicion. Radiologically, acromion tilt on plain radiograph or fracture line on coronal CT view confirmed diagnosis of acromial insufficiency fracture. RESULTS: Comparing both groups, patients with a compromised acromion had no difference in American Shoulder and Elbow Surgeons scores (60 ± 12 versus 64 ± 12; mean difference -4 [95% CI -11 to 2]; p = 0.16), Constant scores (48 ± 10 versus 54 ± 12; mean difference -6 [95% CI -13 to 0]; p = 0.06), forward flexion degree (125 ± 24 versus 130 ± 21; mean difference -5 [95% CI -16 to 6]; p = 0.36), and scaption strength (5 ± 3 versus 6 ± 3; mean difference -1 [95% CI -3 to 0]; p = 0.13). Having acromial compromise was not associated with increased risk of overall complications (30% [7 of 23] versus 19% [13 of 69], relative risk 2 [95% CI 1 to 4]; p = 0.26). However, the only complication that was higher in the acromial compromised group was infection (13% [3 of 23] versus 0% [0 of 69], relative risk not available; p = 0.01). Only the lateralized glenoid prosthesis demonstrated negative association with the acromial insufficiency fracture occurrence; no other factors showed an association. The use of lateralized glenoid prostheses was not observed in patients with acromial insufficiency fracture (0% [0 of 7] acromial insufficiency fracture versus 39% [33 of 85] no acromial insufficiency fracture, relative risk 0 [95% CI 0]; p = 0.047). CONCLUSION: In patients with acquired acromial compromise-such as thinning or fragmented acromion because of advanced cuff tear arthropathy or previous acromioplasty-primary RSA resulted in no different functional outcome score, ROM, shoulder strength, and overall complications compared with patients without acromial compromise. Our findings suggest that a thin or fragmented acromion may not necessarily be exclusion criteria for RSA, potentially aiding surgeons in their decision-making process when treating these patients. However, one of the major complications, postoperative infection, is more frequently observed in patients with acquired acromial compromise. Pre- and postoperative caution would be necessary to prevent and detect infection even when short-term outcomes are favorable in this study. Further studies with large cohorts and long-term follow-up durations are needed. LEVEL OF EVIDENCE: Level III, therapeutic study.

Atelocollagen Injection During Arthroscopic Rotator Cuff Repair for Small- to Medium-Sized Subacute or Chronic Rotator Cuff Tears Enhances Radiographic Tendon Integrity: A Propensity Score-Matched Comparative Study.

PURPOSE: To evaluate the clinical and structural outcomes of using injectable atelocollagen during arthroscopic rotator cuff repair (ARCR) for small- to medium-sized rotator cuff tears. METHODS: This retrospective study reviewed patients with small- to medium-sized full-thickness tears who underwent ARCR from 2016 to 2022 with a minimum 1-year follow-up. Propensity score (PS) matching was used to reduce bias. Tendon integrity was evaluated using magnetic resonance imaging (MRI) at postoperative 6 months. Clinical and structural outcomes were compared between the 2 groups. RESULTS: After PS matching, this study included 181 pairs of patients comparing ARCR with atelocollagen injection and without atelocollagen injection. Range of motion, muscle strength, and functional outcomes were significantly improved in both the atelocollagen group and the control group. Forward elevation and external rotation were significantly worse in the atelocollagen group compared with the control group at 2, 6, and 12 months postoperatively and at the final follow-up. In total, 125 patients (69.1%) in the atelocollagen group and 130 patients (71.8%) in the control group exceeded the minimal clinically important difference in the American Shoulder and Elbow Surgeons score without a significant difference between the 2 groups (P = .509). The mean value of Sugaya grade on postoperative MRI evaluation was 2.03 ± 0.81 for the atelocollagen group and 2.24 ± 0.97 for the control group, with a significant difference between the 2 groups (P = .027). Tendon healing failure was observed in 12 patients (6.6%) in the atelocollagen group and 19 patients (10.5%) in the control group, with no statistical difference between the 2 groups (P = .189). CONCLUSIONS: Atelocollagen injection during ARCR for small- to medium-sized subacute or chronic rotator cuff tears did not show a benefit in clinical outcomes. However, postoperative MRI showed significantly lower Sugaya grade compared with the control group, with no significant difference in retear rate. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

SPECT/CT for Early Detection of Stress Reactions After Reverse Shoulder Arthroplasty: Potential Clinical Significance.

ABSTRACT: The altered biomechanics after reverse shoulder arthroplasty, combined with the accumulation of various stress risers, can lead to stress fractures (SFs) around the prosthesis. The incidence of stress reactions (SRs) after reverse shoulder arthroplasty, characterized by pain and tenderness without radiographic or CT evidence of fractures, is approximately 4.2%, which is comparable to the incidence of SF (6.4%). Among patients with SR, a substantial 32% eventually progress to fractures during clinical follow-up. SPECT/CT is a promising tool that combines morphologic and metabolic information for assessing mechanical bone stress. Therefore, early detection of SR through SPECT/CT can help prevent SF.

Knotless Bioabsorbable Anchors Placed on the Glenoid Face for Arthroscopic Bankart Repair.

BACKGROUND: Quantitative analysis of the glenoid face knotless-type anchor placement for arthroscopic Bankart repair has not been reported. PURPOSE: To evaluate the clinical and radiologic outcomes after arthroscopic Bankart repair using knotless bioabsorbable anchors depending on the anchor location. STUDY DESIGN: Case series, Level of evidence, 4. METHODS: A total of 124 patients (113 men and 11 women; age, 25.6 ± 7.5 years; follow-up time, 46.5 ± 18.2 months [range, 6.2-75.5 months]) who underwent arthroscopic Bankart repair with the bioabsorbable knotless anchor between 2017 and 2021 were included in this study. Among them, 118 patients were observed for >2 years (mean, 48.2 ± 16.8 months [range, 24-75.5 months]) and were analyzed for final clinical and radiologic outcomes. Using postoperative 6-month magnetic resonance imaging, remnant glenoid (%) and labral height were measured. Shoulder range of motion (ROM), radiographic osteoarthritic change, dislocation, apprehension test, and return to sports were recorded. Three groups were established based on the remnant glenoid, which represented the percentage of the exposed glenoid anteroposterior diameter to the original diameter using the best-fit circle method-group A: lower quartile; group B: interquartile; and group C: upper quartile-and variables were analyzed. RESULTS: Overall, the remnant glenoid was 57% ± 6.4% (range, 41.5%-75%) after the surgery. Osteoarthritic change, dislocations, and positive apprehension tests were observed in 5 (4.2%), 4 (3.4%), and 12 (10.2%) patients, respectively. A total of 34 (28.8%) and 64 (54.2%) patients could return to sports without and with restrictions, respectively. Comparing groups A, B, and C, postoperative labral height (7 ± 1, 7 ± 2, and 7 ± 1 mm; P = .623), final osteoarthritic change (1, 4, and 0; P = .440), positive apprehension tests (5, 5, and 2; P = .387), and return to sports (complete/restricted/unable, 6/18/5, 19/29/11, 9/17/4; P = .769) were not different. All ROM were similar across the groups (all P > .054), except for external rotation (ER) at postoperative 6 months (41.3°± 12.8°; 50.2°± 18.5°; and 49.8°± 15.2°; P = .050). However, ER after 1 year was similar across the groups (all P > .544). In further analysis, patients with positive apprehension tests had lower labral height compared with others (5 [4-6] mm and 7 [6-8] mm; P < .001). CONCLUSION: In arthroscopic Bankart repair, the placement of knotless bioabsorbable anchors on the glenoid face, combined with the remplissage procedure or rotator interval closure, resulted in a low recurrence rate and moderate return to sports. However, most patients had some restrictions in returning to sports. Moreover, this technique was not associated with postoperative arthritis and shoulder stiffness, including ER deficit, which was not affected by the position of the anchor on the glenoid face for a minimum 2-year follow-up.

Long-term Effectiveness and Outcome-Determining Factors of Arthroscopic Bankart Repair for Recreational Sports Population: An Assessment of 100 Patients With a Mean Follow-up of 12.7 Years.

BACKGROUND: A limited number of studies have reported the long-term effectiveness of and associated factors for recurrence of anterior shoulder instability after arthroscopic Bankart repair (ABR). PURPOSE: To report the long-term clinical outcomes after ABR in a recreational sports population and identify the associated factors that influence the final instability status. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective study was performed in patients treated with ABR between 2007 and 2013 by a single surgeon. Patient data, magnetic resonance imaging measurements of bone loss and glenoid track, and intra- and perioperative factors were analyzed. After a minimum follow-up of 10 years, patient-reported outcomes including the Western Ontario Shoulder Instability Index score, the Rowe score, the visual analog scale for pain and function, the American Shoulder and Elbow Surgeons score, and sports activity were assessed. The current instability status was classified into 3 groups: stable, apprehensive, and redislocated. These groups were statistically compared with respect to outcomes and associated factors. RESULTS: A total of 100 patients with a mean age of 22.4 ± 5.5 years and a mean follow-up of 12.7 ± 2.1 years were included. At the final follow-up, 38 patients (38%) showed recurrent symptoms: 19 patients (19%) with subjective apprehension and 19 patients (19%) with redislocation, including 10 patients (10%) with revision surgery. At the final follow-up, the redislocated group showed the lowest patient-reported outcomes and return to sports (both P < .001). The apprehensive group also showed a lower Western Ontario Shoulder Instability Index score (P = .011), Rowe score (P = .003), American Shoulder and Elbow Surgeons score (P = .027), and return to sports (P = .005) than the stable group. Participation in contact sports (P = .026), glenoid bone loss (P = .005), size of Hill-Sachs lesion (P = .009), and off-track lesions (P = .016) were all associated with recurrent symptoms, whereas age <20 years (P = .012), participation in contact sports (P = .003), and off-track lesions (P = .042) were associated with redislocation. CONCLUSION: After long-term follow-up in a recreational sports population, ABR demonstrated a 19% rate of subjective apprehension and 19% rate of redislocation, with a gradual decline in clinical outcomes and sports activity over time. Therefore, candidates for ABR should be selected based on consideration of risk factors such as off-track lesions, age <20 years, and participation in contact sports.

Clinical and Structural Outcomes of Arthroscopic Rotator Cuff Repair in Patients Over 75 Years Are Comparable to Those in Younger Patients: A Propensity Score-Matched Comparative Study.

PURPOSE: To compare clinical and structural outcomes of arthroscopic rotator cuff repair (ARCR) in patients over 75 years and those under 75 years and to analyze the factors associated with retear and clinical outcomes after ARCR. METHODS: This retrospective study reviewed patients who underwent ARCR between 2011 and 2021 with at least 2 years of follow-up. Using propensity score matching for sex, tear size, subscapularis involvement, and follow-up time, this study included 54 patients older than 75 years (group A) and 54 patients younger than 75 years (group B). Cuff integrity was evaluated using magnetic resonance imaging (MRI). Structural and clinical outcomes were compared between the 2 groups. RESULTS: The mean improvements in external rotation (P = .030) and the American Shoulder and Elbow Surgeons (ASES) score (P = .043) were significantly higher in group A. Visual analog scales for pain and function, ASES score, and Constant score were significantly improved in both groups (all P = .001). On routine postoperative MRI at 6 months, the retear rate was 20.4% (11/54) in group A and 18.5% (10/54) in group B with no statistical difference between the 2 groups (P = .808). Factor analysis in group A showed that follow-up duration (P = .019), tear size in mediolateral dimension (P = .037), occupation ratio (P = .036), and incomplete repair (P = .034) were associated with retear, and mild glenohumeral arthritis (P = .003) and subscapularis involvement (P = .018) were associated with inferior Constant score. CONCLUSIONS: Clinical and structural outcomes after ARCR in patients aged 75 years or older are comparable to those in patients younger than 75 years. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

Return to Sports Activity After Reverse Total Shoulder Arthroplasty.

Background: There are little published data on return to sports (RTS) after reverse total shoulder arthroplasty (RTSA). Purpose: To (1) determine the rate and timing of RTS after RTSA in an Asian population, (2) analyze predictive factors for RTS, and (3) determine the relationship between RTS after RTSA and clinical/radiological outcomes. Study Design: Case-control study; Level of evidence, 3. Methods: A retrospective review was performed on consecutive patients with diagnosis of irreparable rotator cuff tear (RCT), cuff tear arthropathy (CTA), or degenerative osteoarthritis who underwent RTSA between May 2017 and May 2020. Included were patients who played sports preoperatively in ≤3 years and had ≥2-year follow-up. Patients were divided into 2 groups based on responses to a telephone survey about RTS after RTSA: those who returned to sports (group A) and those who did not (group B). Patient characteristics, pre- and postoperative clinical features and functional scores, and radiologic outcomes (acromial fracture, scapular notching, heterotopic ossification, and loosening of humeral and glenoid component) were compared between the groups. Results: Of 59 eligible patients, 44 patients (28 in group A, 16 in group B) were included. The RTS rate after RTSA was 63.6%, and the mean RTS time was 9.1 months (range, 3-36 months). There was a significant group difference in body mass index (BMI) (group A, 24.3 ± 2.1; group B, 27.1 ± 4.4; P = .01) and preoperative diagnosis (CTA/irreparable RCT/degenerative osteoarthritis diagnoses: group A, 13/12/3; group B, 3/6/7; P = .03). Patients in group A showed significantly higher forward flexion (P = .03) and higher Simple Shoulder Test score (P = .02) than group B at final clinical follow-up. No significant difference in radiological outcomes was found between the groups. Conclusion: Patients with a low BMI and those diagnosed with CTA or irreparable RCT were found to have better RTS rates after undergoing RTSA, and forward flexion and Simple Shoulder Test scores at final follow-up were significantly higher in the RTS group, with no significant differences in complications.

Arthroscopic Repair of Large Subscapularis Tear Over the First Facet.

BACKGROUND: Long-term studies on arthroscopic repair of large subscapularis (SSC) tears over the first facet with or without supraspinatus (SSP) tear are limited. PURPOSE: To assess the structural and clinical outcomes of arthroscopic repair of large SSC tears using magnetic resonance imaging (MRI) and identify the factors related to SSC retear and poor outcomes. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: This study involved 109 patients (84.0 ± 36.2 months of follow-up) who underwent arthroscopic repair of large SSC tears (Yoo and Rhee classification type III [n = 81] or IV [n = 28]) between 2011 and 2019. All patients underwent MRI at 6.1 ± 0.4 months after surgery, and 79 of 109 patients (72.5%) were followed up over 7 years. Clinical outcomes (active range of motion, functional scores, and belly press strength) and final poor clinical outcomes (reoperation, osteoarthritic change, and poor clinical outcome) were recorded. SSP tear size, rotator cuff atrophy and fatty infiltration (Goutallier classification), SSC tendon integrity (intact, intermediate, definite tear), and SSP tendon integrity (Sugaya classification) were evaluated by MRI. RESULTS: The overall SSC retear rate was 8.3% (9/109) (type III, 2/81 [2.5%]; type IV, 7/28 [25.0%]; P < .001). SSC Goutallier grade 4 showed a higher retear rate than grade 3 (7/33 [21.2%] vs 2/33 [6.1%]; P = .149). A large SSP tear (in millimeters) (odds ratio [OR], 1.5; P = .003), SSC Goutallier grade 4 (OR, 10.8; P = .047), and SSP Goutallier grade 3 or 4 (OR, 0.02; P = .013) were independent factors for SSC retear. Clinical outcomes, except for external rotation, were poorer in patients with SSC retear than in those without retear. Final poor clinical outcomes were observed in 27 of 79 patients (34.2%); female sex (OR, 7.7; P = .007), SSC retear (OR, 8.2; P = .025), and SSP retear (OR, 4.7; P = .031) were independent factors. CONCLUSION: Arthroscopic repair of large SSC tears has shown promising structural outcomes for type III tears but not type IV tears. SSC retear was affected by SSC atrophy, as well as SSP tear size and atrophy. Approximately one-third of the final poor clinical outcomes could be predicted, and SSC retear, SSP retear, and female sex were associated with long-term poor clinical outcomes, underscoring the importance of carefully selecting patients for arthroscopic repair of large SSC tears.

Diagnostic Performance of Belly-Press Angle in Predicting the Severity of Subscapularis Tear.

BACKGROUND: Neglected partial subscapularis tears often cause functional impairment even after repair of the supraspinatus and infraspinatus tear is done. Numerous physical examinations for detecting partial subscapularis tears have been described in previous studies. PURPOSE: To analyze the relationship between the preoperative clinical features and the severity of a partial subscapularis tear and to provide diagnostic clues for patients requiring subscapularis repair. STUDY DESIGN: Cohort study (Diagnosis); Level of evidence, 2. METHODS: This retrospective study included 286 patients who underwent arthroscopic shoulder surgery between 2020 and 2022. Preoperative clinical features, including range of motion, functional scores, muscle strength ratio, modified belly-press test (measuring belly-press angle), and bear-hug test, were collected. Magnetic resonance imaging (MRI) evaluation was done according to the Yoo and Rhee classification. Types of subscapularis tear, supraspinatus lesion, and biceps lesion were recorded during arthroscopic surgery. A comparison of preoperative clinical features between the no-repair group (type 2A or less) and surgical repair group (type 2B or more) was done. The optimal cutoff value of the belly-press angle was determined and the diagnostic performance of the belly-press angle, bear-hug test, and MRI were evaluated using the receiver operating characteristic curve. RESULTS: Among 286 patients, 189 (66.1%) had subscapularis tears with type 2A or more. There was a significant difference in muscle strength ratio of the belly-press (P < .001), belly-press angle (P < .001), and bear-hug test (P < .001) between the no-repair group (type 2A or less) and the surgical repair group (type 2B or more). With a belly-press angle of 15° as a new cutoff value, the modified belly-press test showed 67.6% sensitivity, 73.9% specificity, and 69.6% accuracy in detecting type 2B or higher subscapularis tear. CONCLUSION: Patients with type 2A and 2B subscapularis tears (according to the Yoo and Rhee classification) showed differences in belly-press strength ratio, belly-press angle, and bear-hug test. The cutoff value of the 15° belly-press angle showed an accuracy of 69.6% in detecting subscapularis tears with type 2B or higher.

Prospective Randomized Clinical Trial of Arthroscopic Repair Versus Debridement for Partial Subscapularis Tendon Tears More Than Half of the Entire First Facet.

BACKGROUND: Most outcome studies on subscapularis (SSC) tendon tears have focused on large SSC tears rather than partial SSC tendon tears. Therefore, the optimal treatment for partial SSC tendon tears more than half of the first facet of the entire SSC footprint has not yet been clearly defined. PURPOSE: To prospectively investigate the clinical and radiological results between the arthroscopic repair group and the debridement group in SSC partial tear (Yoo and Rhee classification, type 2B: SSC tendon tears of more than half of the entire first facet). STUDY DESIGN: Randomized controlled trial; Level of evidence, 1. METHODS: A total of 65 patients with SSC tendon type 2B tears were randomized to arthroscopic debridement (n = 33) or arthroscopic repair (n = 32). Clinical evaluation of the patients was performed on the day before surgery and 6 months, 1 year, 2 years, and 5 years postoperatively using active range of motion measurements and other validated scores (pain visual analog scale scores, function visual analog scale scores, Constant score, American Shoulder and Elbow Surgeons score). In addition, SSC muscle strength was measured using instruments in the belly-press position. Magnetic resonance imaging (upper and lower SSC muscle diameters, Goutallier grades) was performed on the day before operation as well as 6 months and 2 years postoperatively. RESULTS: There were no clinically or statistically significant differences between the arthroscopic debridement and arthroscopic repair groups with respect to active range of motion, pain visual analog scale scores, function visual analog scale scores, Constant scores, or American Shoulder and Elbow Surgeons scores. There was a statistically significant increase in SSC muscle strength in the repair group compared with the debridement group at 5 years postoperatively (P = .013). Magnetic resonance imaging assessment was also not significantly different between the 2 groups. CONCLUSION: There were no differences in the patient-reported outcomes of patients with partial SSC tears treated with either arthroscopic debridement or repair, although there was an increase in SSC muscle strength associated with repair, the clinical importance of which may warrant further research. REGISTRATION: NCT03183466 (ClinicalTrials.gov identifier).

Changes in Shoulder Trauma during the COVID-19 Pandemic: A South Korean Survey.

Background: This study aimed to investigate the changes in the incidence of shoulder trauma and surgery 1 year after the outbreak of coronavirus disease 2019 (COVID-19) with social restriction compared with 1 year before the pandemic. Methods: Patients managed in our orthopedic trauma center between February 18, 2020, and February 17, 2021 (COVID-19 period) for shoulder trauma were compared with patients managed for the same duration a year ago (non-COVID-19 period; February 18, 2019, to February 17, 2020). The incidence of shoulder trauma, surgery, and mechanism of injury were compared between these periods. Results: The total number of shoulder trauma cases was lower in the COVID-19 period than in the non-COVID-19 period, although the difference was not significant (160 vs. 180 cases, p = 0.278). In addition, traumatic shoulder surgeries decreased during the COVID-19 period (57 vs. 69 cases, p = 0.285). The incidence of shoulder trauma according to four diagnostic classifications (contusion, sprain/subluxation, fracture, and dislocation) and fracture/dislocation types did not differ between the periods. During the COVID-19 period, accidental falls outdoors (45 vs. 67, p = 0.038) and sports-related injuries (15 vs. 29, p = 0.035) significantly decreased, but accidental falls at home (52 vs. 37, p = 0.112) increased compared with those during the non-COVID-19 period, although the difference was not significant. The monthly incidence of shoulder trauma decreased 2 months after the first outbreak (significant in March, p = 0.019), then steadily increased and significantly decreased during the second outbreak (August, p = 0.012). However, the third outbreak (December, p = 0.077) had little effect on the incidence of shoulder trauma. The number of monthly traumatic shoulder surgeries showed a similar pattern to the monthly incidence of shoulder trauma. Conclusions: During the COVID-19 pandemic, annual shoulder trauma cases and surgeries decreased compared to those in the non-COVID-19 period, even though the difference was insignificant. The incidence of shoulder trauma and surgery was significantly reduced in the early COVID-19 period; however, the effect of the pandemic on orthopedic trauma practice was minimal after approximately half a year. Decreases in falls outdoors and sports-related injuries, but an increase in falls at home, were observed during the COVID-19 pandemic.

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.

Arthroscopic Incomplete Rotator Cuff Repair With Patch Augmentation Using Acellular Dermal Matrix Allograft.

Arthroscopic rotator cuff repair has been shown promising clinical outcomes. However, large to massive rotator cuff tears are difficult to completely repair with appropriate tension because of their size or poor tissue quality. An incomplete repair using the "hybrid technique" is one of way to solve this problem by maximizing the contact area between the tendon and the footprint of greater tuberosity. Additionally, the acellular dermal matrix patch augmentation has emerged as an adjuvant technique to enhance the biomechanical properties to promote healing of the repaired construct. This Technical Note describes arthroscopic incomplete rotator cuff repair using the "hybrid technique" with acellular dermal matrix patch augmentation.

Humeral stem with low filling ratio reduces stress shielding in primary reverse shoulder arthroplasty.

PURPOSE: Some patients show severe humeral bone stress shielding even one year after press-fit humeral stem, which can be a risk factor for implant durability. This study compared humeral stress shielding and clinical outcomes between high and low filling ratio (HFR and LFR) stems in primary reverse shoulder arthroplasty (RSA). METHODS: From 2015 to 2020, 104 patients who underwent RSA with a non-cemented standard-length humeral stem were examined. The humeral stems included large press-fit stems (HFR group, 53 patients) or small non-press-fit stems with autogenous cancellous bone grafting (LFR group, 51 patients). The radiologic and clinical outcomes were compared between the groups one year post-operatively. RESULTS: One patient in the LFR group with early infectious dislocation was excluded from the 1-one year evaluation. No stress shielding was observed in 27/50 (54.0%) and 5/53 (9.4%) of patients in the LFR and HFR groups, while 3/50 (6%) and 19/53 (35.8%) patients showed high-stress shielding, respectively. However, the stem alignment change, subsidence, complications and evidence of loosening did not differ between the groups. The final range-of-motion and functional scores were significantly poorer in the LFR group than those in the HFR group, although the difference was minimal. CONCLUSION: Even at one year follow-up, patients receiving LFR stems with autogenous bone grafting had significantly less humeral stress shielding compared to patients with HFR stem with press-fit in primary RSA, without compromising stem stability.

Microinstability characterised by small and easily overlooked anterior labral or Hill-Sachs lesions can be managed with arthroscopic anterior labral repair.

PURPOSE: Some young individuals present with shoulder pain without a definite history or complaint of instability. However, careful history taking, physical examination, and high-quality magnetic resonance imaging may reveal evidence of instability of which the patient is unaware. Therefore, a clearer definition of these ambiguous patients is needed. This study aimed to report the characteristics and surgical outcomes of patients with microinstability compared to those of patients with classic recurrent anterior shoulder instability. METHODS: From 2005 to 2018, 35 patients with microinstability (group M) underwent arthroscopic anterior labral repair (AALR) and were compared to 35 sex- and age-matched patients with classic recurrent anterior shoulder instability (group C) who also underwent AALR. Baseline characteristics, preoperative apprehension test findings, preoperative imaging for the presence of anterior labral and Hill-Sachs lesions, preoperative and postoperative (over 2 years) range of motion (ROM) and functional scores, final complications, and patient satisfaction were analysed. RESULTS: The most common chief complaints in groups M and C were pain (29/35) and both pain and instability (27/35), respectively. Only pain during the apprehension test was predominant in group M (M vs. C, 27 vs. 1, p < 0.001). High incidence of chronic repetitive injuries (26/35) and acute trauma (28/35) were observed in groups M and C, respectively. Over half of the patients in group M showed anterior labral lesions on magnetic resonance arthrography (MRA, 18/35), and 21 patients had Hill-Sachs lesions on MRA/three-dimensional computed tomography. Finally, 29 patients showed either anterior labral or Hill-Sachs lesions on preoperative imaging. The lesion severity was higher in group C than that in group M. All patients underwent AALR with/without the remplissage procedure, with no significant differences in final clinical outcomes, complications, and patient satisfaction between the groups. CONCLUSIONS: Microinstability is diagnostically challenging and can be diagnosed in young patients with ambiguous shoulder pain during motion, without instability. Pain on anterior apprehension test and subtle labral and/or Hill-Sachs lesion on imaging study could be diagnostic clues. This condition can be managed with arthroscopic anterior labral repair with or without the remplissage procedure. The possibility of microinstability in young patients with shoulder pain should always be considered, and small anterior labral or Hill-Sachs lesions should be closely monitored. LEVEL OF EVIDENCE: III.

Clinical and structural outcome of intra-articular steroid injection for early stiffness after arthroscopic rotator cuff repair.

PURPOSE: Direct comparative results of patients with early stiffness after arthroscopic rotator cuff repair (ARCR) with and without steroid injection are still unclear. This study aimed to evaluate the clinical and structural effect of intra-articular steroid injection for early stiffness after ARCR. METHODS: From 2011 and 2016, a total of 417 patients who underwent ARCR for less than medium-sized tears with 35.8 ± 22.6 months follow-up were retrospectively analyzed. Patients with shoulder stiffness [forward flexion (FF) < 120˚] or pain at 2 months after ARCR were performed intra-articular steroid injection, and four groups were established [+ stiffness/ + injection (SI, 158 patients), + stiffness/-injection (SNI, 92 patients), -stiffness/ + injection (NSI, 33 patients), and -stiffness/-injection (NSNI, 134 patients)]. Shoulder range-of-motion (ROM) and functional score changes for over two years were analyzed, and six month tendon integrity were evaluated using magnetic resonance imaging. RESULTS: Comparing SI and SNI group, ROM (except internal rotation) and functional score changes did not differ during the early period (2-6 and 2-12 months). However, comparing whether steroid injected (SI/NSI) or not (SNI/NSNI), the formers showed significantly higher improvement of both ROM and functional scores during the early and late period (2-24 months). A six month tendon integrity was not different across four groups and whether steroid injected or not. CONCLUSIONS: Intra-articular steroid injections do not appear to have a short-term clinical improving effect by comparing patients with stiff shoulders after ARCR with and without steroid injections. However, intra-articular steroid injection at two months after ARCR did not affect the tendon integrity at post-operative six months.

Factors affecting internal rotation after reverse shoulder arthroplasty.

BACKGROUND: The limitation or loss of internal rotation (IR) after the surgery is a major problem in reverse shoulder arthroplasty (RSA). The particular factors associated with postoperative IR remain unclear. We aimed to analyze the predictors of IR after RSA. METHODS: We included primary RSA patients with the following implants and a minimum of 1-year follow-up: Wright Aequalis (n = 25), DJO Encore (n = 29), Biomet Comprehensive (n = 40), and Exactech Equinoxe (n = 29). Age, sex, dominant hand, primary diagnosis, implant type, preoperative critical shoulder angle, pre- and postoperative acromiohumeral distance, lateral offset of implant, glenosphere inclination, peg-glenoid rim distance (PGRD), glenosphere overhang, scapular notching, subscapularis (SSc) repair, pre- and postoperative ROM, and functional scores were assessed. IR was assessed using a 10-point scale based on the following anatomical levels: from the greater trochanter to the buttocks (2 points), from the sacrum to L4 (4 points), from L3 to L1 (6 points), from T12 to T8 (8 points), and from T7 to T1 (10 points). Univariable and multivariable analyses were performed to identify the factors affecting the IR after RSA. RESULTS: One hundred twenty-three shoulders (123 patients) with a mean follow-up of 30.59 ± 19.55 (range, 12-83) months were evaluated. In the univariable analysis, preoperative diagnosis [odds ratio (OR) = 0.243, P = 0.001], implant type (P = 0.002), PGRD (OR = 1.187, P = 0.003), and preoperative IR (P < 0.001) were found to be factors associated with postoperative IR. Preoperative IR was the only factor associated with postoperative IR in the multivariable analysis (P < 0.001). Patients with preoperative IR scores of 10 or 8 points showed significantly better IR after RSA than those with preoperative IR scores of 2 or 4 points (10 points vs. 2 or 4 points; OR = 15.433, P = 0.002, 8 points vs. 2 or 4 points; OR = 6.078, P < 0.001). CONCLUSION: Preoperative IR was the only independent factor for IR after RSA. Patients with excellent preoperative IR had better postoperative IR than those with poor preoperative IR. Preoperative diagnosis, implant type, SSc repair, implant lateralization, glenosphere inferior placement, and scapular notching were not identified as independent predictors of IR after RSA in our sample size.

Preoperative rotator cuff tendon integrity, tear size, and muscle atrophy and fatty infiltration are associated with structural outcomes of arthroscopic revision rotator cuff repair.

PURPOSE: A few studies have focused on factors predisposing to retear after arthroscopic revision rotator cuff repair (ARRCR). This study aimed to retrospectively evaluate (1) the structural and clinical outcomes of ARRCR and (2) pre- and intraoperative factors affecting the integrity of the rotator cuff (RC) tendon by focusing on preoperative RC tendon integrity, tear size, muscle hypotrophy and fatty infiltration. METHODS: Patients who underwent ARRCR between 2006 and 2016 were reviewed. Preoperative variables included demographic data, RC tendon integrity, tear size, and muscle hypotrophy and fatty infiltration on preoperative magnetic resonance imaging (MRI). Intraoperative variables included repair technique and completeness of repair. The visual analog scale for pain (PVAS), functional VAS (FVAS), American Shoulder and Elbow Surgeons scores, and shoulder range of motion (ROM) were assessed. Postoperative tendon integrity was evaluated using over 6-month follow-up MRI. Patients were classified into groups A (healed) and B (retear), and their variables were compared. RESULTS: Overall 65 patients with a mean follow-up of 49.5 ± 30.2 (range, 24.0-148.9) months were analyzed. Fifty-six of 65 (86.2%) patients underwent MRI at 9.1 ± 9.7 (range, 4.4-40.2) months after ARRCR, and 20 of 56 (35.7%) patients (group B) exhibited retear. Group A (36/56, 64.3%) showed higher functional scores and ROMs than group B at the final follow-up, with significant differences in the FVAS scores (Group A versus B: FVAS, 7.6 ± 1.8 versus 6.4 ± 1.9, p = 0.036). Intraoperative variables, including preoperative tendon integrity (p = 0.021), tear size (p = 0.007), supraspinatus and infraspinatus muscle hypotrophy and fatty infiltration (p < 0.001 and p = 0.046), and completeness of repair (p = 0.030), differed significantly between the groups. Multivariate analysis revealed that preoperative supraspinatus muscle hypotrophy and fatty infiltration were independent predisposing factors for retear after ARRCR [odds ratio = 7.5, 95% confidence interval (CI) 1.1-55.8, p = 0.048]. CONCLUSION: The retear was found in 20/56 patients (35.7%) after ARRCR for less than massive rotator cuff tears in this limited study population. Preoperative tendon integrity, tear size, supraspinatus and infraspinatus muscle hypotrophy and fatty infiltration, and completeness of repair was revealed to be associated with tendon integrity following ARRCR. Among them, preoperative supraspinatus muscle atrophy and fatty infiltration were the independent factors for retear after ARRCR, although generalization is limited. LEVEL OF EVIDENCE: IV.

A Novel Retensioning Technique for Arthroscopic Repair of PASTA Lesions: A Clinical and Radiologic Outcome Study of 24 Shoulders.

BACKGROUND: There is no consensus on the ideal treatment for partial articular supraspinatus tendon avulsion (PASTA) lesions without tendon damage. PURPOSE: To introduce a novel "retensioning technique" for arthroscopic PASTA repair and to assess the clinical and radiologic outcomes of this technique. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A retrospective analysis was performed on 24 patients whose PASTA lesion was treated using the retensioning technique between January 2011 and December 2015. The mean ± SD patient age was 57.6 ± 7.0 years (range, 43-71 years), and the mean follow-up period was 57.6 ± 23.4 months (range, 24.0-93.7 months). Sutures were placed at the edge of the PASTA lesion, tensioned, and fixed to lateral-row anchors. After surgery, shoulder range of motion (ROM) and functional scores (visual analog scale [VAS] for pain, VAS for function, American Shoulder and Elbow Surgeons [ASES] score, Constant score, Simple Shoulder Test, and Korean Shoulder Score) were evaluated at regular outpatient visits; at 6 months postoperatively, repair integrity was evaluated using magnetic resonance imaging (MRI). RESULTS: At 12 months postoperatively, all ROM variables were improved compared with preoperative values, and shoulder abduction was improved significantly (136.00° vs 107.08°; P = .009). At final follow-up (>24 months), the VAS pain, VAS function, and ASES scores improved, from 6.39, 4.26, and 40.09 to 1.00, 8.26, and 85.96, respectively (all P < .001). At 6 months postoperatively, 21 of the 24 patients (87.5%) underwent follow-up MRI; the postoperative repair integrity was Sugaya type 1 or 2 for all of these patients, and 13 patients showed complete improvement of the lesion compared with preoperatively. CONCLUSION: The retensioning technique showed improved ROM and pain and functional scores as well as good tendon healing on MRI scans at 6-month follow-up in the majority of patients. Thus, the retensioning technique appears to be reliable procedure for the PASTA lesion.

Posterior repair of isolated type 2 superior labrum anterior-posterior lesion prevents external rotation deficiency: long-term outcome study.

PURPOSE: This study aimed to evaluate the outcomes of arthroscopic type 2 superior labrum anterior-posterior (SLAP) lesion repair in the general population and compare clinical outcomes according to patient age and repair site. METHODS: Between 2005 and 2018, patients who underwent arthroscopic repair for isolated type 2 SLAP lesions were retrospectively reviewed. Baseline characteristics, pre- and postoperative [1-year and > 2-year (final)] shoulder range-of-motion, and functional scores, comprising the pain visual analogue scale (PVAS), functional VAS, and American Shoulder and Elbow Surgeons (ASES) score, were evaluated. Return to overhead activities and subjective satisfaction were assessed at the final follow-up, and patients were divided by age [group YB (< 40 years] and group OB (≥ 40 years)] and repair site [group P (only posterior labrum repair) and group AP (anterior and posterior labrum repair)]. Overall patient outcomes were analysed and compared between groups. RESULTS: This study included 54 patients (45 men) with a mean age of 37.1 ± 8.3 years. The mean follow-up was 90.8 ± 51.3 months. Two patients experienced early failure, and one patient had a ruptured biceps tendon during the follow-up period. Final functional scores improved compared to their preoperative scores in all patients, except three (all p < 0.001). Fifty patients (98.0%) were satisfied, and 39 patients (76.5%) were able to perform overhead sports without restriction. In 25 patients who attended more than 7 years of follow-up (mean, 11.3 ± 2.7 years), 21 patients (84%) had an ASES score ≥ 80, and all patients had PVAS ≤ 2. There was no significant difference in clinical outcomes between groups YB and OB. The final median external rotation was significantly more restricted in group AP than in group P (40 [25-65] vs. 60 [50-70], p = 0.002). CONCLUSION: Arthroscopic type 2 SLAP repair induced good short- and long-term clinical outcomes, return to overhead activities, and subjective satisfaction in the general population, regardless of age, due to the careful evaluation of patient history, physical examination, and imaging studies. However, performing only posterior repair seems sufficient since anterior labral SLAP lesion repair can limit ER. Isolated type 2 SLAP lesion posterior repair only is, thus, recommended to reduce external rotation deficit risk and increase satisfaction, regardless of patient age. STUDY DESIGN: Case series. LEVEL OF EVIDENCE: Level IV.