The subcoracoid distance is correlated with pain and internal rotation after reverse shoulder arthroplasty.

Background: A proposed etiology of anterior shoulder pain and limited internal rotation after reverse shoulder arthroplasty (RSA) is impingement of the humeral component on the coracoid or conjoint tendon. The primary goal of this study was to investigate radiographic surrogates for potential coracoid or conjoint tendon impingement and their relationship to postoperative pain and internal rotation after RSA. Methods: A retrospective review of a clinical registry was performed to identify patients with (1) primary RSA, (2) minimum 2-year clinical follow-up, and (3) satisfactory postoperative axillary lateral radiographs. The primary radiographic measurement of interest was the subcoracoid distance (SCD), defined as the distance between the posterior aspect of the coracoid and the anterior glenosphere. Additional measurements were as follows: anterior glenosphere overhang, posterior glenosphere overhang, native glenoid width, lateralization of glenosphere relative to the coracoid tip, lateralization shoulder angle, and distalization shoulder angle. The primary clinical outcome of interest was the 2-year postoperative Visual Analog Scale score. Secondary outcomes were (1) internal rotation (IR) defined by spinal level (IRspine), (2) IR at 90 degrees of abduction, (3) American Shoulder and Elbow Surgeons score, (4) forward flexion, and (5) external rotation at 0 degrees of abduction. Linear regression analyses were used to evaluate the relationship of the various radiographic measures on the clinical outcomes of interest. Results: Two hundred seventeen patients were included. There was a statistically significant relationship between the SCD and Visual Analog Scale scores: B = -0.497, P = .047. There was a statistically significant relationship between the SCD and IRspine: B = -1.667, P < .001. Metallic lateralization was also positively associated with improving IRspine; increasing body mass index was negatively associated. There was a statistically significant relationship between the SCD and IR at 90 degrees of abduction: B = 5.844, P = .034. Conclusion: For RSA with a 135° neck shaft angle and lateralized glenoid, the postoperative SCD has a significant association with pain and IR. Decreasing SCD was associated with increased pain and decreased IR, indicating that coracoid or conjoint tendon impingement may be an important and potentially under-recognized etiology of pain and decreased IR following RSA. Further investigations aimed toward identifying a critical SCD to improve pain and IR may allow surgeons to preoperatively plan component position to improve clinical outcomes after RSA.

Rates of subacromial notching are low following reverse shoulder arthroplasty with a 135° inlay humeral component and a lateralized glenoid.

Background: Lateralization in reverse shoulder arthroplasty (RSA) decreases bony impingement and improves rotational range of motion, but has been theorized to increase the risk of subacromial notching (SaN). The purpose of this study was to evaluate the presence of SaN following RSA and its relationship with lateralization with a 135° inlay humeral component. The secondary purpose was to assess the association of SaN with functional outcomes. Methods: A retrospective review was performed from a multicenter prospectively collected database on patients who underwent primary RSA from 2015 to 2021. All RSAs were performed with a 135° inlay humeral component. SaN was defined as bony erosion with sclerotic margins on the undersurface of the acromion on final follow-up radiographs not present preoperatively. Postoperative implant positioning (inclination, distalization, and lateralization) were evaluated on minimum 1-year postoperative radiographs. Regression analyses were performed on implant and clinical variables to assess for risk factors. A separate analysis was performed to determine the association of SaN with clinical outcomes. Results: SaN was identified in 13 out of 442 shoulders (2.9%). Age, sex, body mass index, smoking status, diabetes mellitus, arm dominance had no relationship with SaN. Neither glenoid sided lateralization nor humeral offset were associated with SaN risk. Other implant characteristics such as distalization, glenosphere size, and postoperative inclination did not influence SaN risk. The presence of SaN did not affect patient-reported outcomes (American Shoulder and Elbow Surgeons: P = .357, Visual Analog Scale: P = .210) or range of motion. Conclusion: The rate of SaN is low and not associated with glenoid or humeral prosthetic lateralization when using a 135° inlay humeral component. When SaN occurs, it is not associated with functional outcomes or range of motion at short-term follow-up.

Obesity is associated with improvement in functional outcome but lower internal rotation after reverse shoulder arthroplasty.

Background: The role of obesity as an independent risk factor for increased complications following reverse shoulder arthroplasty (RSA) continues to generate debate. While no standardized body mass index (BMI) cutoff values for shoulder arthroplasty exist, many surgeons are concerned about the potential for poor outcomes and decreased range of motion (ROM) in patients with a high BMI. The purpose of this study was to compare functional outcomes in obese and nonobese patients preoperatively and at short-term follow-up after RSA. Methods: A retrospective review was performed of a prospectively maintained, multicenter database of primary RSAs performed by 14 surgeons between 2015 and 2019 with minimum 2-year follow-up. A total of 245 patients met the study criteria, including 111 obese (BMI >30) and 134 nonobese (BMI <30) patients. Patient-reported outcomes (PROs) as well as ROM measurements were compared between the 2 groups. Results: At baseline, obese patients had significantly lower American Shoulder and Elbow Surgeons (36.6 vs. 42.0, P = .014), Western Ontario Osteoarthritis of the Shoulder scores (33.1 vs. 37.8, P = .043), external rotation at 90° (19° vs. 28°, P = .007), internal rotation (IR) spinal level (L5 vs. L4, P = .002), and belly press strength (P = .003) compared to the nonobese cohort. There were no statistical differences in 2-year outcomes (PROs, ROM, and strength) other than a worse IR (spinal level) in the low BMI group (L4 vs. L3, P = .002). In linear regression analyses controlling for confounding variables, increasing BMI was negatively correlated with preoperative external rotation (B = -0.591, P = .034) and preoperative IR spinal level (B = 0.089, P = .002). Increasing BMI was not correlated with postoperative external rotation at 90° (B = 0.189, P = .490) but was associated with worse postoperative IR by spinal level (B = 0.066, P = .043). Conclusions: Obese patients have greater restrictions in external and internal rotation as well as American Shoulder and Elbow Surgeons and Western Ontario Osteoarthritis of the Shoulder scores at baseline prior to RSA. However, there are no major differences in postoperative PROs or ROM measurements between obese and nonobese patients apart from a worse active IR by spinal level in the obese group (L4 vs. L3, P = .002). This study suggests that an RSA procedure does not need to be restricted solely based on BMI.

Robert H. Cofield, MD, Award for Best Oral Presentation 2023: Up to 8 mm of glenoid-sided lateralization does not increase the risk of acromial or scapular spine stress fracture following reverse shoulder arthroplasty with a 135° inlay humeral component.

BACKGROUND: Glenoid-sided lateralization in reverse shoulder arthroplasty (RSA) decreases bony impingement and improves rotational range of motion, but has been theorized to increase the risk of acromial or scapular spine fractures (ASFs). The purpose of this study was to assess if glenoid-sided lateralization even up to 8 mm increases the risk for stress fracture following RSA with a 135° inlay humeral component. METHODS: A retrospective review was performed from a multicenter prospectively collected database on patients who underwent primary RSA from 2015 to 2021. All RSAs were performed with a 135° inlay humeral component. Varying amounts of glenoid lateralization were used from 0 to 8 mm. Preoperative radiographs were reviewed for the presence of acromial thinning, acromiohumeral distance (AHD), and inclination. Postoperative implant position (distalization, lateralization, and inclination) as well as the presence of ASF was evaluated on minimum 1-year postoperative radiographs. Regression analyses were performed on component and clinical variables to assess for factors predictive of ASF. RESULTS: Acromial or scapular spine fractures were identified in 26 of 470 shoulders (5.5%). Glenoid-sided lateralization was not associated with ASF risk (P = .890). Furthermore, the incidence of fracture did not vary based on glenoid-sided lateralization (0-2 mm, 7.4%; 4 mm, 5.6%; 6 mm, 4.4%; 8 mm, 6.0%; P > .05 for all comparisons). RSA on the dominant extremity was predictive of fracture (odds ratio [OR] 2.21, 95% confidence interval [CI] 1.20-5.75; P = .037), but there was no relationship between patient age, sex, preoperative acromial thinning, or diagnosis and risk of fracture. Although there was no difference in mean postoperative AHD between groups (P = .443), the pre- to postoperative delta AHD was higher in the stress fracture group (2.0 ± 0.7 cm vs. 1.7 ± 0.7 cm; P = .015). For every centimeter increase in delta AHD, there was a 121% increased risk for fracture (OR 2.21, 95% CI 1.33-3.68; P = .012). Additionally, for every 1-mm increase in inferior glenosphere overhang, there was a 19% increase in fracture risk (P = .025). CONCLUSION: Up to 8 mm of glenoid-sided metallic lateralization does not appear to increase the risk of ASF when combined with a 135° inlay humeral implant. Humeral distalization increases the risk of ASF, particularly when there is a larger change between pre- and postoperative AHD or higher inferior glenosphere overhang. In cases of pronounced preoperative superior humeral migration, it may be a consideration to avoid excessive postoperative distalization, but minimizing bony impingement via glenoid-sided lateralization appears to be safe.

Quantifying Threshold Scores for Patient Satisfaction After Massive Rotator Cuff Repair for the Interpretation of Mid-Term Patient-Reported Outcomes.

PURPOSE: To establish minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) values for 4 patient-reported outcomes (PROs) in patients undergoing arthroscopic massive rotator cuff repair (aMRCR): American Shoulder and Elbow Surgeons (ASES) score, Subjective Shoulder Value (SSV), Veterans Rand-12 (VR-12) score, and the visual analog scale (VAS) pain. In addition, our study seeks to determine preoperative factors associated with achieving clinically significant improvement as defined by the MCID and PASS. METHODS: A retrospective review at 2 institutions was performed to identify patients undergoing aMRCR with minimum 4-year follow-up. Data collected at the 1-year, 2-year, and 4-year time points included patient characteristics (age, sex, length of follow-up, tobacco use, and workers' compensation status), radiologic parameters (Goutallier fatty infiltration and modified Collin tear pattern), and 4 PRO measures (collected preoperatively and postoperatively): ASES score, SSV, VR-12 score, and VAS pain. The MCID and PASS for each outcome measure were calculated using the distribution-based method and receiver operating characteristic curve analysis, respectively. Pearson and Spearman coefficient analyses were used to determine correlations between preoperative variables and MCID or PASS thresholds. RESULTS: A total of 101 patients with a mean follow-up of 64 months were included in the study. The MCID and PASS values at the 4-year follow-up for ASES were 14.5 and 69.4, respectively; for SSV, 13.7 and 81.5; for VR-12, 6.6 and 40.3; and for VAS pain, 1.3 and 1.2. Greater infraspinatus fatty infiltration was associated with failing to reach clinically significant values. CONCLUSIONS: This study defined MCID and PASS values for commonly used outcome measures in patients undergoing aMRCR at the 1-year, 2-year, and 4-year follow-up. At mid-term follow-up, greater preoperative rotator cuff disease severity was associated with failure to achieve clinically significant outcomes. LEVEL OF EVIDENCE: Level IV, case series.

Arthroscopic Repair of Massive Rotator Cuff Tears Leads to Functional Improvement in Most Patients at 4-Year Follow-up.

Purpose: To assess functional outcomes and healing 4 years after arthroscopic repair of massive rotator cuff tears (MRCTs). Methods: We conducted a retrospective study of patients who underwent arthroscopic rotator cuff repair of an MRCT-defined as a complete 2-tendon tear or a tear greater than 5 cm in any dimension-performed by 2 surgeons at different institutions between January 2015 and December 2018. At a minimum of 4 years postoperatively, patient-reported outcomes collected included the visual analog scale pain score, American Shoulder and Elbow Surgeons (ASES) score, Veterans RAND 12 (VR-12) score, and Subjective Shoulder Value (SSV) score. Repair technique and concomitant procedures were also gathered. Tendon healing was evaluated via ultrasound at final follow-up. Results: Functional outcomes were available for 101 patients at a mean of 63.6 ± 8.8 months (range, 48-82 months) postoperatively. Mean ASES scores improved from 40.1 to 78 (P < .001); VR-12 scores, from 37.1 to 47.7 (P < .001); and SSV scores, from 36.7 to 84.6 (P < .001). Forward flexion improved from 126° to 144° (P = .001), external rotation remained unchanged (from 47° to 44°, P = .268), and internal rotation improved by 2 spinal levels (from L4 to L2, P = .0001). Eighty-eight percent of patients (89 of 101) were satisfied with the procedure, and only 5% underwent reverse shoulder arthroplasty within the study period. Among the 39 patients who underwent postoperative ultrasound to assess healing, 56% showed complete tendon healing. There was no difference in healing or outcomes according to tear pattern. Additionally, tendon healing did not affect outcomes. Conclusions: Arthroscopic repair of MRCTs leads to functional improvements and patient satisfaction in most cases at 4-year follow-up. The rates of patients achieving the minimal clinically important difference were 77.5%, 87.6%, 59.7%, and 80.6% for the ASES score, SSV score, VR-12 score, and visual analog scale pain score, respectively. Complete tendon healing is difficult to achieve but does not appear to limit functional improvements. Level of Evidence: Level IV, therapeutic case series.

Female Sex and Higher Infraspinatus Fatty Infiltration Are Linked to Dissatisfaction at a Minimum Follow-Up of 4 Years after Arthroscopic Repair of Massive Rotator Cuff Tears.

Purpose: To evaluate patient satisfaction at a minimum of 4 years after arthroscopic rotator cuff repair (ARCR) of massive rotator cuff tears (MRCT), to identify preoperative and intraoperative characteristics associated with satisfaction, and to compare clinical outcomes between satisfied and dissatisfied patients. Methods: A retrospective review on prospectively collected data was conducted on ARCRs of MRCTs performed at 2 institutions between January 2015 and December 2018. Patients with a minimum 4-year follow-up, preoperative and postoperative data, and primary ARCR of MRCTs were included for analysis. Patient satisfaction was analyzed according to patient demographics, patient-reported outcome measures (American Shoulder and Elbow Surgeons score [ASES], visual analog scale [VAS] for pain, Veteran Rands 12-item health survey [VR-12], and Subjective Shoulder Value [SSV]), range of motion (forward flexion [FF], external rotation [ER], and internal rotation [IR]), tear characteristics (fatty infiltration, tendon involvement, and tear size), and clinical significant measures (minimal clinical important difference [MCID], substantial clinical benefit [SCB], and patient-acceptable symptomatic state [PASS]) for ASES and SSV. Rotator cuff healing was also assessed with ultrasound in 38 patients at final follow-up. Results: A total of 100 patients met the study's criteria. Overall, 89% of patients were satisfied with ARCR of a MRCT. Female sex (P = .007) and increased preoperative infraspinatus fatty infiltration (P = .005) were negatively associated with satisfaction. Those in the dissatisfied cohort had significantly lower postoperative ASES (80.7 vs 55.7; P = .002), VR-12 (49 vs 37.1; P = .002), and SSV scores (88.1 vs 56; P = .003), higher VAS pain (1.1 vs 4.1; P = .002) and lower postoperative range of motion in FF (147° vs 117°; P = .04), ER (46° vs 26°; P = .003), and IR (L2 vs L4; P = .04). Rotator cuff healing did not have an influence on patient satisfaction (P = .306). Satisfied patients were more likely to return to work than dissatisfied patients (97% vs 55%; P < .001). Conclusions: Nearly 90% of patients who undergo ARCR for MRCTs are satisfied at a minimum 4-year follow-up. Negative preoperative factors include female sex and increased preoperative infraspinatus fatty infiltration, but no association was observed with rotator cuff healing. Furthermore, dissatisfied patients were less likely to report a clinically important functional improvement. Level of Evidence: Level IV, prognostic case series.

Remote Patient Monitoring of Postoperative Rehabilitation.

Postoperative rehabilitation is a critical part of the treatment algorithm for patients with shoulder issues. When patients could not go to in-person therapy, many therapists pivoted to a remote option, and several application-based rehabilitation programs emerged. This article will discuss the shift to remote patient rehabilitation and will highlight the benefits and potential pitfalls of remote rehabilitation. It will also discuss ways to monitor patients remotely as they are performing their postoperative rehabilitation exercises. Finally, it will discuss how these remote platforms can be used, and what the user experience is like for the patient and the surgeon.

Patient reported outcomes and ranges of motion after reverse total shoulder arthroplasty with and without subscapularis repair.

Background: In performing reverse total shoulder arthroplasty (rTSA), the role of repairing the subscapularis has been debated. Our objective was to determine the effect of subscapularis repair following rTSA on postoperative shoulder ranges of motion and patient reported outcome scores (PROs). Methods: A prospective registry was reviewed to establish a cohort of primary rTSA patients with a 135-degree humeral implant, with a minimum of 2 years of follow-up. Variables collected included demographics, subscapularis repair information, diagnosis, glenosphere size, and glenoid lateralization information. Outcomes collected were range of motion measurements, subscapularis strength, and multiple generic and shoulder PROs. Multivariable linear regression models were created to predict these 2-year outcomes. Results: The 143-patient cohort had a mean age of 69 years with 68% of patients undergoing subscapularis repair. After adjustment in the multivariable models, whether the subscapularis was repaired did not significantly predict a 2-year forward elevation, external rotation, internal rotation, subscapularis strength, Western Ontario Osteoarthritis of the Shoulder score, VR-12 scores, Constant Score, or American Shoulder and Elbow Surgeons Shoulder Scores. Increased glenoid lateralization significantly predicted greater internal rotation, higher VR-12 physical score, and higher Constant Score. There were no dislocations in either group. Conclusions: After adjusting for patient and implant factors, subscapularis repair was not associated with a 2-year postoperative range of motion, strength, or any PROs suggesting that repairing the subscapularis may not affect functional outcome. Increased glenoid lateralization through the baseplate and glenosphere independently predicted better internal rotation, VR-12 physical score, and Constant Scores indicating a benefit to lateralization during rTSA.

No difference in range of motion in reverse total shoulder arthroplasty using standard or constrained liners: a matched cohort study.

Background: Prosthetic instability is one of the most common short-term complications following reverse total shoulder arthroplasty (RTSA). Numerous strategies exist to attempt to mitigate this complication, including utilization of constrained polyethylene humeral liners. A concern of constrained humeral liners is that they may come at the expense of restricted rotational range of motion (ROM). The purpose of the present study is to compare range of ROM and patient-reported outcomes (PROs), and satisfaction among matched cohorts using constrained vs. unconstrained liners after RTSA. Methods: A multicenter shoulder arthroplasty registry was retrospectively reviewed to identify patients with two-year clinical follow-up after RTSA with constrained liners used at the surgeon's discretion. All patients had the same inlay humeral prosthesis with a 135° neck shaft angle. This study cohort was matched 1:2 to control patients who underwent RTSA with standard liners based on age, sex, total glenoid-sided lateralization, glenosphere diameter, and surgery performed on the dominant arm. Improvement in PROs and ROM was compared between groups. Results: Twenty-two patients were identified who underwent RTSA with a constrained humeral liner; these were compared to 44 matched patients with standard liners. The groups were found to have no notable differences in demographics, baseline PROs and ROM. At two years postoperatively, both cohorts demonstrated improvements in all PROs without statistically significant differences between the two groups. There were no differences between groups in improvement in any ROM measure, including forward flexion (constrained: 54°, standard: 57°, P = .771), external rotation at the side (constrained: 42°, standard: 41°, P = .906) or internal rotation at 90° of abduction (constrained: 24°, standard: 20°, P = .587). Conclusions: For an inlay humeral prosthesis with a 135° neck shaft angle, utilization of a constrained liner for RTSA demonstrates no significant difference in ROM or PROs compared to a well-matched cohort of patients who underwent RTSA with a standard polyethylene humeral liner. These are reassuring data for using constrained liners when there is intraoperative concern for prosthetic instability.

A 135° short inlay humeral stem leads to comparable radiographic and clinical outcomes compared with a standard-length stem for reverse shoulder arthroplasty.

Background: Humeral stem length in reverse total shoulder arthroplasty (RTSA) has decreased in recent years in an attempt to preserve more bone and facilitate stem removal in the revision setting. The purpose of this study was to compare the clinical and radiographic outcomes of a short- to standard-length stem RTSA. The authors hypothesized that there would be no difference in radiographic or clinical outcomes at short-term follow-up. Methods: Patients who underwent RTSA using a press-fit standard- or short-length humeral component with a consistent geometry (Univers Revers, or Revers Apex; Arthrex, Inc., Naples, FL, USA) were evaluated in a multicenter retrospective review. The minimum clinical follow-up was 2 years. Immediate postoperative radiographs were used to assess initial alignment and filling ratios. In addition, radiographs at 2 years were evaluated for signs of stress shielding and/or loosening. Clinical outcome scores and range of motion were evaluated at the final follow-up and compared between groups. Results: A total of 220 patients with short-stem RTSA and 357 patients with standard-length stem RTSA were analyzed. There was no difference in baseline function between short- and standard-length stem patients. Patients in the short stem group had higher postoperative American Shoulder and Elbow Surgeons (84.6 vs. 80.8; P = .014) and Western Ontario Osteoarthritis of the Shoulder (86.5 vs. 82.7; P = .025). Patients in the short stem group also had greater postoperative active forward flexion (139° vs. 132°; P = .003) and internal rotation with the arm at 90° of abduction (43° vs. 32°; P < .001) than patients in the standard-length group. Radiographically, there was a higher metaphyseal (P = .049) and diaphyseal (P < .001) fill ratio in the short stem group, although there was no difference in postoperative alignment, radiographic signs of loosening, or revision for loosening between groups (all P > .05). Conclusion: A short inlay stem leads to comparable radiographic findings and revision-free survival compared with a standard-length stem when placed with a press-fit technique for RTSA. Clinical outcomes are also equivalent or slightly improved with a short stem compared with a standard-length stem.

A Comparison of Central Screw versus Post for Glenoid Baseplate Fixation in Reverse Shoulder Arthroplasty Using a Lateralized Glenoid Design.

The purpose of this study was to compare the short-term clinical and radiographic outcomes of a lateralized glenoid construct with either a central screw or post. Methods: A multicenter retrospective study was conducted of reverse shoulder arthroplasties (RSAs) with minimum 2-year clinical followup. All RSAs implanted had a 135° neck shaft angle (NSA) and a modular circular baseplate. The patients were divided into two cohorts based on the type of central fixation for their glenoid baseplates (central post (CP) vs. central screw (CS)). The clinical outcomes, rates of revisions, and available radiographs were evaluated. Results: In total, 212 patients met the study criteria. Postoperatively, both groups improved over their preoperative baseline. There were no significant differences between the cohorts in any PROs at 2 years postoperatively. No findings of gross loosening were identified in either cohort. Implant survival was 98.6% at 2 years. Conclusions: When using a lateralized glenoid implant with a 135° NSA inlay humeral component, both central post and central screw baseplate fixation provide good clinical outcomes, survivorship, and improvements in ROM at 2 years. There is no difference in loosening or revision rates between the types of baseplate fixation at a minimum of 2 years postoperatively.

Short-term clinical and radiographic outcomes of a hybrid all-polyethylene glenoid based on preoperative glenoid morphology.

BACKGROUND: The primary purpose of this study was to compare 2-year anatomic total shoulder arthroplasty (TSA) functional and radiographic outcomes between Walch type A and B glenoids treated with an all-polyethylene glenoid designed for hybrid fixation with peripheral cement and central osseous integration. The secondary purpose was to evaluate outcomes based on central peg technique. The hypotheses were that there would be no difference in short-term radiographic or functional outcome scores based on preoperative glenoid morphology or central peg technique. METHODS: We performed a multicenter retrospective review of patients who underwent TSA with the same hybrid all-polyethylene glenoid and had minimum 2-year follow-up. Patient-reported outcomes and radiographic outcomes were analyzed based on preoperative Walch morphology and central peg technique. Radiographic analysis included preoperative glenoid morphology; preoperative and postoperative glenoid version, glenoid inclination, and posterior humeral head subluxation; and postoperative glenoid radiolucencies according to the Wirth and Lazarus classifications. RESULTS: A total of 266 patients with a mean age of 64.9 ± 8.2 years were evaluated at a mean of 28 months postoperatively. Postoperatively, there were significant improvements in all functional outcome measures (P < .001), range-of-motion measures (forward elevation, external rotation at 0°, external rotation at 90°, internal rotation by spinal level, and internal rotation at 90°; P < .001), and strength measures (Constant, external rotation, and modified belly press; P < .001). There were no clinically meaningful differences in functional outcomes or statistically significant differences in radiographic appearance between Walch type A and B glenoids. Subgroup analysis revealed that glenoids with a cemented central peg had the worst radiographic outcomes based on Lazarus scoring. CONCLUSION: Patients undergoing TSA with a hybrid in-line pegged glenoid have excellent clinical outcomes at short-term follow-up regardless of preoperative glenoid morphology. Different central peg techniques do not appear to play a significant role in the risk of glenoid component lucencies at 2 years postoperatively.

Does lateralizing the glenosphere center of rotation by 4 mm decrease scapular notching in reverse shoulder arthroplasty with a 135° humeral component?

Background: Scapular notching continues to be associated with reverse shoulder arthroplasty (RSA) and is thought to lead to fewer outcomes. Decreasing the humeral neck-shaft angle (NSA) has been associated with decreased incidence of scapular notching. Lateralizing the glenosphere center of rotation (COR) has also been proposed to decrease notching; however, its effect in lower NSA RSA is less understood. The purpose of this study was to compare the impact of the medial (0 mm) and lateral (4 mm) COR on the incidence of scapular notching and clinical outcomes after RSA with a 135° NSA humeral component. Methods: We performed a multicenter retrospective comparative cohort of 82 patients with cuff tear arthropathy (41 in each cohort) who underwent RSA with a 135° NSA humeral component and a glenosphere COR of either 0 mm (medialized COR [MCOR]) or 4 mm (lateralized COR [LCOR]) of lateralization. RSA was performed using the same 135° humeral system and baseplate design. All patients had 2-year radiographic and clinical follow-up. Postoperative radiographs were evaluated for scapular notching. Clinical outcomes included American Shoulder and Elbow Surgeons scores, visual analog pain scale, Simple Assessment Numeric Evaluation, and active range of motion. Results: The overall incidence of scapular notching was 22.0%. There was no significant difference in scapular notching between cohorts: 24.4% in the MCOR and 19.5% in the LCOR (P = .625). Both cohorts had significant improvements in American Shoulder and Elbow Surgeons scores, visual analog pain scale, Simple Assessment Numeric Evaluation, and active range of motion postoperatively (P < .005). Improvements did not significantly differ between cohorts. The presence of scapular notching did not have a significant negative effect on any clinical outcome measure. Complications occurred in 5 patients (2 MCORs and 3 LCORs), none of which occurred in patients with scapular notching. Discussion and conclusion: Lateralizing the glenosphere COR by 4 mm does not significantly affect the incidence of scapular notching in RSA when using a 135° NSA humeral component at short-term follow-up. Furthermore, such offset does not significantly improve functional outcome scoring systems or range of motion when compared with the MCOR (0 mm). Scapular notching did not have a negative impact on any clinical outcome measure or complication rate in this series.

Initial and 1-Year Radiographic Comparison of Reverse Total Shoulder Arthroplasty With a Short Versus Standard Length Stem.

INTRODUCTION: In an effort to preserve bone, humeral stems in reverse total shoulder arthroplasty (RTSA) have gradually decreased in length. The purpose of this study was to compare the immediate postoperative radiographic appearance of short-length with standard-length RTSA stems. METHODS: Patients who underwent RTSA using a press-fit standard-length or short-length humeral implant with a consistent geometry (Univers Revers or Revers Apex) were evaluated in a multicenter retrospective review. Initial postoperative radiographs were used to assess initial alignment and filling ratios. In addition, radiographs were evaluated for early signs of stress shielding and/or loosening. Clinical outcome scores and range of motion were also evaluated. RESULTS: Overall, 137 short-length stems and 139 standard-length stems were analyzed. Initial radiographs demonstrated a significantly higher percentage of stems placed in neutral alignment in the short-stem group (95.6% vs 89.2%, P = 0.045). Similar metaphyseal filling ratios were seen between groups, but a significantly higher diaphyseal filling ratio was observed in the short-stem group (57% vs 34%, P < 0.001). Less calcar osteolysis (2.2% vs 12.9%; P = 0.001) and fewer overall number of radiographic changes (tuberosity resorption, lucencies, and subsidence) (0.7% vs 5.0%; P = 0.033) were seen with short stems compared with the standard-length stems. CONCLUSION: RTSA with a short-stem humeral implant demonstrates excellent radiographic outcomes, including low rates of loosening and subsidence at 1 year, with less early calcar osteolysis compared with a standard-length stem. LEVEL OF EVIDENCE: III (Case-control).

Reverse total shoulder arthroplasty for patients with preserved active elevation and moderate-to-severe pain: a matched cohort study.

BACKGROUND: Patients undergoing reverse total shoulder arthroplasty (RTSA) predictably report reduced pain and improved function postoperatively. However, it is not known if patients with differing preoperative active motion achieve the same benefit after surgery. The purpose of the present study is to evaluate patient-reported outcomes (PROs), range of motion (ROM), and satisfaction after RTSA in patients with moderate-to-severe pain with preserved active preoperative ROM compared with matched controls with restricted preoperative active ROM. METHODS: A multicenter shoulder arthroplasty registry was utilized to identify patients with at least two-year clinical follow-up after RTSA with a 135° implant. The study cohort with preserved motion included patients with greater than one standard deviation above the overall mean for preoperative forward elevation (FE) (140°) as well as a preoperative visual analog pain scale (VAS) ≥ 5.0. The control cohort with more restricted motion had preoperative FE of less than 140° and also with preoperative VAS ≥5.0. The control patients were matched 2:1 to study patients by age (±2 years), sex, and preoperative VAS (±1.5). Outcomes measured were as follows: PROs, ROM, strength, and strength and satisfaction. RESULTS: Twenty-seven patients were identified that comprised the preserved preoperative FE study cohort; 54 patients were included in the restricted elevation cohort as controls. The groups were similar at baseline for demographics, surgical diagnoses, and most PROs, other than the Constant-Murley, which was higher in the preserved motion cohort. At two years postoperatively, both cohorts demonstrated similar PROs, strength, and ROM (other than internal rotation with the arm abducted 90 degrees) and had a similar number of patients who rated the RTSA as meeting or exceeding their expectations. The change in ROM from preoperatively was significantly different with the restricted cohort, achieving a larger increase in forward flexion (51 ± 26° vs. -13 ± 35°, P < .001). CONCLUSION: Patients indicated for RTSA with preserved preoperative FE and moderate pain achieve similar final ROM, pain reduction, increases, and strength compared with patients who undergo RTSA with restricted preoperative FE. Despite losing on average 13 degrees of FE from preoperatively by two years postoperatively, patients with preserved preoperative FE are comparably satisfied with their outcome.

Lesser Tuberosity Osteotomy Does Not Appear to Compromise Fixation or Function Compared With Peel in Short-Stem Anatomic Shoulder Arthroplasty.

Several methods are available for subscapularis management in total shoulder arthroplasty (TSA). The goal of this study was to compare radiographic and clinical outcomes of short-stem TSA stratified by subscapularis management technique. A multicenter trial was completed evaluating primary short-stem TSA performed with a subscapularis peel (n=80) or lesser tuberosity osteotomy (LTO) (n=59). The primary outcome measure was subscapularis function, as measured by internal rotation and strength at 1 year postoperatively. Secondary outcomes included patient-reported outcomes, radiographic changes, and implant loosening. Patients in the peel group obtained better active internal rotation by spinal level (P=.004). No difference was seen between groups for internal rotation with 90° shoulder abduction (P=.862) or belly press (P=.903). Statistically significant improvements in functional outcomes were seen without clinical differences. Radiographic changes showed no difference in stem shift, subsidence, or at-risk loosening rate. Anterior subluxation of the humerus was observed among 2% of the LTO group vs 17% of the peel group (P=.006). At short-term follow-up, those in the peel group appear to have a better final spinal level of internal rotation, whereas those in the LTO group have a significantly lower rate of anterior humeral subluxation. Both LTO and subscapularis peel appear safe for short-stem TSA, with no radiographic evidence of loosening. [Orthopedics. 2022;45(3):151-155.].