Publications

Internal rotation (IR) is not reliably improved after reverse shoulder arthroplasty (RSA). This study aimed to identify surgical parameters that predict kinematics of the hand-to-back motion (H2B) after RSA and to identify associations between kinematics and clinical outcomes after RSA. We hypothesized that less humeral retroversion, more lateralization and a larger glenosphere would predict kinematics associated with favorable outcomes post-RSA. Thirty-five patients performed H2B while synchronized biplane radiographs were collected. Digitally reconstructed radiographs, constructed from patient-specific bone plus implant models, were matched to the biplane radiographs to determine kinematics. The total contribution to motion, the end position, peak angles, and range of motion (ROM) were found for all glenohumeral and scapular rotations. The path of the center of the humeral insert on the glenosphere was calculated. Patient-reported outcomes, clinical ROM, and strength were measured. Associations were determined between intraoperative variables and kinematics as well as between kinematics and outcomes. The results demonstrated that glenosphere tilt predicted glenohumeral and scapular kinematics; these kinematics were associated with IR ROM, strength, and more favorable patient-reported outcomes. A larger glenosphere predicted a center of contact that was associated with more strength in IR. All components of scapular rotation were associated with favorable outcomes, suggesting rehabilitation focusing on scapular motion may improve outcomes post-RSA. Glenosphere tilt and size predicted kinematics that were associated with range of motion, strength, and patient-reported outcomes.

BACKGROUND: Arthroscopic revision rotator cuff repairs (RCRs) exhibit lower healing rates and inferior outcomes compared to primary repairs. There is limited evidence regarding the use of bioaugmentation in the setting of revision RCRs. Autologous conditioned plasma (ACP) is a promising adjunct that has been shown to improve healing rates and patient-reported outcomes (PROs) in the primary setting. In addition, bioinductive patches such as collagen bovine patches have become a popular adjunct for stimulating healing in the primary setting. The aim of this study is to assess the outcomes after use of ACP and collagen bovine patch augmentation for revision arthroscopic RCR. We hypothesized improved PROs and higher healing rates would be observed with bioaugmentation for revision repair compared to without.

METHODS: This was an institutional review board-approved, retrospective case-control study from 2 fellowship-trained surgeons that included all consecutive patients undergoing arthroscopic revision RCR from 2010 to 2021. Reconstruction such as superior capsular reconstruction, partial revision repair, and less than 1-year follow-up were excluded. The bioaugmentation cohort received ACP and/or collagen bovine patch at the time of revision repair. PROs were collected from all patients including American Shoulder and Elbow Surgeons Standardized Assessment Form (ASES), visual analog scale for pain (VAS), Brophy score, and Patient-Reported Outcomes Measurement Information System (PROMIS) mental and physical scores. Failure of revision RCR was defined as an ASES postoperative total score less than 60 or a symptomatic retear confirmed on magnetic resonance imaging. Student's t-test was used for all comparisons of continuous variables. Chi-squared test used for comparison of all categorical variables. Statistical significance was set at <0.05.

RESULTS: Thirty-eight patients met inclusion criteria with average follow-up of 3.5 ± 1.7 years. There was no significant difference in follow-up between patients with and without bioaugmentation. Of the 38 patients, 14 patients met failure criteria. There was no significant difference in the rate of failure between the bioaugmentation cohort (6/19, 31.6%) vs. patients who did not receive bioaugmentation (8/19, 42.1%) (P = .74). In addition, no significant differences were identified for ASES (64.6 ± 20.1 vs. 57.5 ± 17.2, P = .32), Brophy (6.4 ± 5.2 vs. 6.0 ± 4.1, P = .84), PROMIS Mental (13.4 ± 3.9 vs. 11.7 ± 3.2), or PROMIS Physical (12.8 ± 3.1 vs. 11.9 ± 3.2) scores between the bioaugmentation vs. no bioaugmentation groups.

CONCLUSION: Bioaugmentation with a bioinductive collagen patch or ACP demonstrated similar failure and PROs compared to without bioaugmentation in the setting of revision RCR.

Cadaveric and computer simulations suggest lateral humeral offset (LHO) and humeral retroversion (HR) are associated with strength and range of motion (ROM) after reverse total shoulder arthroplasty (rTSA), butin vivodata is lacking. This study aimed to evaluate the effects of implant parameters (i.e. LHO and HR) on strength and ROM. LHO and HR were measured using pre-operative and post-operative computed tomography (CT) scans. Postoperative strength was measured across three planes of motion using a Biodex isokinetic dynamometer. Postoperative active and passive ROM during forward elevation, external rotation (ER), and internal rotation (IR) were assessed using a goniometer or spinal level. 30 rTSA patients (14 M, 16F, age: 71.8 ± 6.7yrs) participated with an average postoperative follow-up of 2.4 ± 1.1 years. Regarding strength, higher post-op LHO values were predictive of greater postoperative strength across all movements. However, lateralization of the implant beyond pre-op values (i.e. post-op LHO > pre-op LHO) was associated with poorer strength performance across all ranges of motion. Similar to strength outcomes, greater deviations from pre-op LHO was predictive of poorer IR ROM. Lastly, patients with minimal deviations in HR (post-op HR within 10° of pre-op HR) and minimal deviations in LHO (post-op LHO ≤ pre-op LHO) displayed the greatest postoperative ER ROM. Anatomic restoration of LHO combined with anatomic restoration of HR may be ideal for maximizing strength and ROM following rTSA. Overlateralization beyond anatomic may have negative consequences. Optimal implant lateralization and version may need to be individualized based on preoperative values.

BACKGROUND: Anterior shoulder instability is a common pathology seen especially in young men and highly active patient populations. Subluxation is a commonly encountered clinical issue, yet little is known about the effects of first-time subluxation compared with dislocation on shoulder stability and clinical outcomes after surgical stabilization.

PURPOSE: To compare revision and redislocation rates as well as patient-reported outcomes (PROs) between subluxators and dislocators after a first-time anterior shoulder instability event.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: Included were patients who underwent operative intervention for a first-time anterior instability event between 2013 and 2020 at a single institution. Exclusion criteria were posterior/multidirectional instability, revision surgery, and recurrent instability. The main outcomes of interest were the rates of redislocation and revision. Demographics and surgical details were retrospectively collected. Instability was categorized as subluxation (no documentation of formal shoulder reduction) or dislocation (documented formal shoulder reduction). Labral tear location and size were determined from preoperative magnetic resonance imaging scans. PROs and return-to-sport, redislocation, and revision rates were collected from prospective survey data.

RESULTS: A total of 256 patients (141 subluxators and 115 dislocators) were available for analysis. There were no significant differences in baseline demographics or preoperative physical examination findings. Rates of bony Bankart lesions were comparable, but Hill-Sachs lesions were more commonly present in dislocators compared with subluxators (88.7% vs 53.9%; P < .01). There were no group differences in labral tear size, incidence of concomitant posterior or superior labrum anterior-posterior tears, or number of anchors used. Rates of remplissage were comparable between groups. Prospectively collected survey data of 60 patients (35 subluxators, 25 dislocators) were collected at 6.4 and 7.1 years of follow-up, respectively. Rates of recurrent dislocation (11.8% vs 20.0%) and revision (8.8% vs 16.0%) were comparable between subluxators and dislocators, respectively. All PROs and return-to-sport rates were comparable between groups.

CONCLUSION: Subluxators and dislocators may present with comparable rates of redislocation and revision surgery even at midterm follow-up. Both cohorts may further present with comparable injury characteristics and PROs. Given the findings, future prospective studies comparing outcomes of first-time instability events are needed.

OBJECTIVES: This study aimed to compare short-term outcomes following Total Shoulder Arthroplasty (TSA) and Humeral Head Resurfacing (HHR) in patients with glenohumeral osteoarthritis (GHOA).

METHODS: A retrospective analysis included patients who had undergone either TSA or HHR for GHOA at a single institution. Baseline demographics, complications, range of motion (active forward flexion, FF and active external rotation, ER), visual analog scores (VAS), and Subjective Shoulder Values (SSV) were collected.

RESULTS: A total of 69 TSA and 56 HHR patients were analyzed. More HHR patients were laborers (44% versus 21%, P=0.01). There were more smokers in the TSA group (25% versus 11%, P=0.04) and more cardiovascular disease in the HHR cohort (64% versus. 6%, p<0.0001). Postoperative FF was similar, but ER was greater in the HHR (47° ± 15°) vs. TSA group (40° ± 12°, P = 0.01). VAS was lower after TSA vs. HHR (median 0, IQR 1 versus median 3.7, IQR 6.9, p<0.0001), and SSV was higher after TSA (89% ± 13% vs. 75% ± 20% after HHR; p<0.0001). Post-operative impingement was more common after HHR (32% vs. 3% for TSA, p<0.0001). All other complications were equivalent.

CONCLUSION: While younger patients and heavy laborers had improved ER following HHR, their pain relief was greater after TSA. Decisions on surgical technique should be based on patient-specific demographic and anatomic factors.

Studies have shown that glenoid- and humeral-sided bone loss may be present in up to 73-93% of individuals with recurrent anterior shoulder instability. As such, bone loss must be addressed appropriately, as the amount of bone loss drives surgical decision making and influences outcomes. Methods to describe and measure bone loss have changed over time. Originally, glenoid and humeral bone loss were viewed separately. However, the concepts of bipolar bone loss, the glenoid track (GT), and "on/off-track" lesions arose, highlighting the interplay between the two entities in contributing to recurrent instability. Classically, "off-track" lesions have been described as those Hill-Sachs interval (HSI) greater than the GT, and have been shown to result in higher rates of re-instability when addressed nonoperatively or with Bankart repair alone. More recently, further attention has been given to "on-track" lesions (HSI < GT). The new concept of "distance to dislocation" (DTD) has gained popularity. DTD is calculated as the difference between the GT and HSI, and literature evaluating DTD suggests that not all "on-track" lesions should be treated in the same manner. The purpose of this concept review article is twofold: (I) describe glenoid, humeral, and bipolar bone loss in the setting of anterior shoulder instability; and (II) elaborate on the new concept of "DTD" and its use in guidance of management.

PURPOSE: To determine the comparative accuracy and precision of routine magnetic resonance imaging (MRI) versus magnetic resonance (MR) arthrogram in measuring labral tear size as a function of time from a shoulder dislocation.

METHODS: We retrospectively evaluated consecutive patients who underwent primary arthroscopic stabilization between 2012 and 2021 in a single academic center. All patients completed a preoperative MRI or MR arthrogram of the shoulder within 60 days of injury and subsequently underwent arthroscopic repair within 6 months of imaging. Intraoperative labral tear size and location were used as standards for comparison. Three musculoskeletal radiologists independently interpreted tear extent using a clock-face convention. Accuracy and precision of MR labral tear measurements were defined based on location and size of the tear, respectively. Accuracy and precision were compared between MRI and MR arthrogram as a function of time from dislocation.

RESULTS: In total, 32 MRIs and 65 MR arthrograms (total n = 97) were assessed. Multivariate analysis demonstrated that intraoperative tear size, early imaging, and arthrogram status were associated with increased MR accuracy and precision (P < .05). Ordering surgeons preferred arthrogram for delayed imaging (P = .018). For routine MRI, error in accuracy increased by 3.4° per day and error in precision increased by 2.3° per day (P < .001) from time of injury. MR arthrogram, however, was not temporally influenced. Significant loss of accuracy and precision of MRI compared with MR arthrogram occurred at 2 weeks after an acute shoulder dislocation.

CONCLUSIONS: Compared with MR arthrogram, conventional MRI demonstrates time-dependent loss of accuracy and precision in determining shoulder labral tear extent after dislocation, with statistical divergence occurring at 2 weeks.

LEVEL OF EVIDENCE: Level II, retrospective radiographic diagnostic study.

BACKGROUND: Margin convergence (MC) and superior capsular reconstruction (SCR) are common treatment options for irreparable rotator cuff tears in younger patients, although they differ in associated costs and operative times. The purpose of this study was to compare range of motion, patient-reported outcomes (PROs), and reoperation rates following MC and SCR. We hypothesized superior outcomes after SCR relative to MC regarding functional outcomes, subjective measures, and reoperation rates.

METHODS: This was a multicenter retrospective review of 59 patients from 3 surgeons treating irreparable rotator cuff tears with either MC (n = 28) or SCR (n = 31) and minimum 1-year follow-up from 2014-2019. Visual analog scale (VAS) for pain, Subjective Shoulder Value (SSV), active forward flexion (FF), external rotation (ER), retear rate, and conversion rate to reverse shoulder arthroplasty were evaluated. t tests and χ2 tests were used for continuous and categorical variables, respectively (P < .05).

RESULTS: Baseline demographics, range of motion, and magnetic resonance imaging findings were similar between groups. Average follow-up was 31.5 months and 17.8 months for the MC and SCR groups, respectively (P < .001). The MC and SCR groups had similar postoperative FF (151° ± 26° vs. 142° ± 38°; P = .325) and ER (48° ± 12° vs. 46° ± 11°; P = .284), with both groups not improving significantly from their preoperative baselines. However, both cohorts demonstrated significant improvements in VAS score (MC: 7.3 to 2.5; SCR: 6.4 to 1.0) and SSV (MC: 54% to 82%; SCR: 38% to 87%). There were no significant differences in postoperative VAS scores, SSV, and rates of retear or rates of conversion to arthroplasty between the MC and SCR groups. In patients with preoperative pseudoparesis (FF < 90°), SCR (n = 9) resulted in greater postoperative FF than MC (n = 5) (141° ± 38° vs. 67° ± 24°; P = .002).

CONCLUSION: Both MC and SCR demonstrated excellent postoperative outcomes in the setting of massive irreparable rotator cuff tear, with significant improvements in PROs and no significant differences in range of motion. Specifically for patients with preoperative pseudoparesis, SCR was more effective in restoring forward elevation. Further long-term studies are needed to compare outcomes and establish appropriate indications.