BACKGROUND: Reverse shoulder arthroplasty (RSA) offers promising functional outcomes for young patients, yet challenges persist in restoring internal rotation (IR). This study aimed to assess the restoration of IR after RSA in patients younger than 60 years of age and analyze the factors affecting IR recovery.
METHODS: A retrospective multicenter study was conducted, examining the functional outcome of patients who underwent RSA, with a minimum follow-up period of 2 years. Two subgroups of patients who underwent primary RSA were analyzed separately with respect to active internal rotation with the elbow at the side (AIR1): \"difficult AIR1\" and \"easy AIR1.\"
RESULTS: The study included 136 patients (overall series) with a mean age of 51.6 years. The overall series showed statistically significant improvement in active range of motion (RoM), pain, and Constant scores, especially with active IR (p ​< ​0.01). According to etiology, statistically significant improvement (p ​< ​0.05) in active IR was observed for fracture sequelae, primary osteoarthritis, and rheumatoid arthritis, whereas no statistically significant improvement in IR was observed for tumor, revision, and cuff-tear arthropathy (p ​> ​0.05). In subgroup analysis, patients with easy AIR1 displayed a statistically significant lower body mass index and better Constant score mobility, as well as improved motion in forward elevation and active IR (p ​< ​0.05). No statistically significant associations were found between improved IR and prosthetic design or subscapularis repair. Scapular notch, lysis of the graft, and teres minor atrophy were significantly associated with better active IR (p ​< ​0.05).
CONCLUSIONS: RSA improves active RoM, pain, and functional outcomes in patients aged under 60. However, the degree of improvement in IR may vary depending on several factors and the underlying etiologies. These insights are crucial for patient selection and counseling, guiding RSA optimization efforts.
METHODS: IV.

BACKGROUND: The role of the subscapularis following reverse shoulder arthroplasty (RSA) remains controversial as repair could restore adequate internal rotation and shoulder stability, but might compromise external rotation. The purpose of this multi-centre study, on a large cohort of RSAs performed using the deltopectoral approach, was to determine the effect of subscapularis preoperative status and intraoperative repair on range of motion, clinical scores and rates of complications at a minimum follow-up of 2 years.
OBJECTIVE: Repair of a functional subscapularis grants better internal rotation and stability without compromising external rotation.
METHODS: We retrospectively reviewed records of all RSAs (n=916) performed by 14 surgeons that participated in a large national society symposium, and excluded 234 operated by the anterosuperior approach, 42 operated for rheumatoid arthritis, fractures, instability or post traumatic sequalae, and eight that had adjuvant latissimus dorsi tendon transfer (LDTT). This left 632 RSAs, in which the subscapularis was detached in 594, and repaired after detachment in 495. Patients completed pre- and postoperative Constant Score and postoperative Subjective Shoulder Value (SSV). Active forward elevation, active external rotation (ER), and active internal rotation (IR) were recorded pre- and postoperatively. Complications following RSA that required conservative treatment, reoperation without implant removal, as well as reoperation with implant removal were recorded.
RESULTS: Of the initial cohort of 632 shoulders, 120 (19%) were lost to follow-up, 12 (2%) died due to causes unrelated to RSA, and 26 (4%) were revised with implant removal. Of the remaining 474 shoulders, 259 (55%) had a functional repaired subscapularis (Group FR), 59 (12%) had a non-functional repaired subscapularis (Group nFR), whereas 68 (14%) had a not repaired subscapularis (Group nR). Comparison of patient demographics revealed no significant differences among the three groups. Postoperative Constant Score (p=0.031) and SSV (p=0.016) were significantly different among the three groups, but effect sizes were small and not clinically relevant. Differences in postoperative ER as well as postoperative IR were not significant among the three groups: 91 (35%) gained functional IR in Group FR, 11 (19%) in Group nFR, and 13 (19%) in Group nR. Three shoulders (1.2%) reported subjective instability and 1 (0.4%) dislocated in Group FR, but none in either Groups nFR or nR.
CONCLUSIONS: Despite statistically significant differences in Constant Score and SSV among the three groups, the clinical relevance of these differences is negligible, so repair of functional subscapularis has little or no influence on functional outcomes. During RSA by deltopectoral approach, repair of a functional subscapularis could slightly improve internal rotation in some patients but does not compromise external rotation, forward elevation or clinical scores, while repair of a non-functional subscapularis, compared to non-repair, did not improve range of motion or clinical scores.
METHODS: III; retrospective comparative.

UNASSIGNED: To determine, from a sizable cohort of reverse shoulder arthroplasty (RSA), whether the deltopectoral (DP) or anterosuperior (AS) approach grant better outcomes at a minimum follow-up of 24 months.
UNASSIGNED: The authors reviewed 743 RSAs in patients with primary osteoarthritis (OA) with or without rotator cuff lesions and secondary OA due to rotator cuff tears. The DP approach was used in 540 and the AS approach in 203. Pre- and post-operative constant scores (CSs) and shoulder range of motion were recorded.
UNASSIGNED: Of the initial cohort of 743 shoulders, 193 (25.7%) were lost to follow-up, 16 (2.1%) died, and 33 (4.4%) were revised; 540 shoulders were operated using DP approach (73%), of which 22 were revised (4.1%), while 203 were operated using the AS approach (27%), of which 11 were revised (5.4%). Propensity score matching resulted in two groups: 172 shoulders operated by DP approach, and 88 shoulders operated by AS approach. Comparing outcomes of the matched groups at 2 or more years also revealed that, compared to the AS approach, the DP approach resulted in significantly better post-operative CSs (67.3 ± 14.0° vs 60.8 ± 18.3, P = 0.017), active forward elevation (137° ± 27.4° vs 129° ± 29.8; P = 0.031).
UNASSIGNED: At 2 or more years following RSA, the DP approach granted significantly better CS (by 6.5 points) and active forward elevation (by 8°) compared to the AS approach. The differences observed are clinically relevant and must be considered to manage patient expectations following RSA and for selecting surgical approach depending on their functional needs.
UNASSIGNED: III, comparative study.

Background: The evidence of hydrotherapy after rotator cuff repair (RCR) is limited as most studies either used it as an adjuvant to standard land-based therapy, or have different initiation timing. This study aimed to compare hydrotherapy and land-based therapy with varying immobilization time. Methods: Patients who underwent RCR with a 10-days or 1-month immobilization duration (early or late rehabilitation) were prospectively randomized. Results: Constant scores significantly differed at three months only, with the best score exhibited by the late hydrotherapy group (70.3 ± 8.2) followed by late land-based (61.0 ± 5.7), early hydrotherapy (55.4 ± 12.8) and early land-based (54.6 ± 13.3) groups (p < 0.001). There was a significant interaction between rehabilitation type and immobilization duration (p = 0.004). The effect of hydrotherapy compared to land-based therapy was large at three months when initiated lately only (Cohen\'s d, 1.3; 95%CI, 0.9-1.7). However, the relative risk (RR) of postoperative frozen shoulder or retear occurrence for late hydrotherapy was higher compared to early hydrotherapy (RR, 3.9; 95%CI, 0.5-30.0). Conclusions: Hydrotherapy was more efficient compared to land-based therapy at three months only and if initiated lately. Even though initiating hydrotherapy later brought greater constant scores at three months, it might increase the risk of frozen shoulders or retear compared to early hydrotherapy.

UNASSIGNED: Shoulder strength is an essential assessment to monitor the outcome of treatment interventions. Isometric strength assessment in the Constant Score (CS) was initially measured with a cable tensiometer or spring balance (SB). Some authors have questioned the validity of this strength assessment and the resulting CS. The purpose of this study was to investigate the concordance of strength measurements using an unsecured SB vs. isometric dynamometer and outline the impact of these methods on the CS.
UNASSIGNED: In the context of routine clinical examination as well as participation in a Swiss national cohort study, shoulder strength was measured to calculate baseline (before surgery) and 6-month postoperative CS in adult rotator cuff tear patients who had undergone primary arthroscopic rotator cuff repair. Measurements of each of the operated and contralateral shoulders were made per patient routinely using an unsecured SB and study-specific using an isometric dynamometer in patients with the shoulder at 90° abduction in the scapular plane. Absolute and change values of strength and CS data were presented in scatter plots and assessed using concordance correlation coefficients (CCCs) and Bland-Altman plots.
UNASSIGNED: Between June 2020 and October 2021, baseline strength measurements from the operated shoulder of 78 patients ranged from 0.0 to 13.6 kg with a CCC of 0.64 (P < .001) and a mean difference of 0.81 kg between the SB and dynamometer methods. There were 89 measurements of the contralateral healthy shoulder that ranged from 3.6 to 15.6 kg; CCC and mean strength difference were 0.76 (P < .001) and 0.70 kg, respectively. At 6 months postsurgery, strength measurements of the operated shoulder ranged from 1.4 to 12.0 kg with a CCC of 0.66 (P < .001) and mean strength difference of 0.9 kg (n = 68). Respective 6-month measurements of the contralateral side (n = 52) ranged from 2.0 to 15.9 kg with a CCC of 0.73 (P < .001) and mean strength difference of 0.03 kg.
UNASSIGNED: Absolute and change values in shoulder strength assessments using an unsecured SB and isometric dynamometer are fairly concordant with mean differences of less than 1 kg between methods. With the variability of strength differences among patients, interpretation of these values for individual patients may be challenging. Nonetheless, unsecured SB and dynamometer methods share only slight and clinically unimportant differences that can provide similar group mean values for use in research along with the calculation of the CS.

The purpose of this multi-centre study was to report outcomes of a large cohort of reverse shoulder arthroplasty (RSA) at a minimum follow-up of two years and to determine patient and surgical factors that influence postoperative outcomes. The hypothesis was that surgical indication, surgical approach, and implant design would affect clinical outcomes significantly.
The authors reviewed records of 743 RSAs in patients with primary osteoarthritis (OA) with or without rotator cuff (RC) tears, secondary OA due to RC tears, and irreparable massive rotator cuff tears (mRCT). The deltopectoral (DP) approach was used in 540 and the anterosuperior (AS) approach in 203. Pre- and postoperative Constant scores (CS) were recorded. Multivariable linear analyses were performed to determine if CS was associated with indications for surgery, surgical approach, or implant design.
Of the 743 shoulders, 193 (25.7%) were lost to follow-up, 16 (2.1%) died, and 33 (4.4%) were revised, leaving 501 for analysis. At a mean follow-up of 3.2 ± 0.9 years, net improvement in CS was 29.2 ± 17.0. Multivariable analyses revealed that postoperative CS decreased with age and was worse in shoulders that had preoperative rotator cuff deficiency and in shoulders operated by the AS approach. Multivariable analyses also revealed worse net improvement in shoulders operated for secondary OA due to RC tears or for irreparable mRCT, as well as shoulders operated by the AS approach.
This large multi-centre study confirms that, at two or more years following RSA, Constant scores are not associated with implant design, but rather with rotator cuff deficiency and surgical approach. Multivariable analysis revealed that postoperative CS was worse for shoulders with preoperative rotator cuff deficiency and for shoulders operated by the AS approach. Multivariable analysis also revealed that net improvement in CS was worse in shoulders treated for secondary OA due to RC tears and for shoulders with irreparable mRCT, as well as for shoulders operated by the AS approach.

BACKGROUND: The Constant score (CS) is often used clinically to assess shoulder function and includes a muscle strength assessment only for abduction. The aim of this study was to evaluate the test-retest reliability of isometric shoulder muscle strength during various positions of abduction and rotation with the Biodex dynamometer and to determine their correlation with the strength assessment of the CS.
METHODS: Ten young healthy subjects participated in this study. Isometric shoulder muscle strength was measured during 3 repetitions for abduction at 10° and 30° abduction in the scapular plane (with extended elbow and hand in neutral position) and for internal and external rotation (with the arm at 15° abduction in the scapular plane and elbow flexed at 90°). Muscle strength tests with the Biodex dynamometer were measured in 2 different sessions. The CS was acquired only in the first session. Intraclass correlation coefficients (ICCs) with 95% confidence interval, limits of agreement, and paired t tests for repeated tests of each abduction and rotation task were calculated. Pearson\'s correlation between the strength parameter of the CS and isometric muscle strength was investigated.
RESULTS: Muscle strength did not differ between tests (P > .05) with good to very good reliabilities for abduction at 10° and 30°, external rotation and internal rotation (ICC >0.7 for all). A moderate correlation of the strength parameter of the CS with all isometric shoulder strength parameters was observed (r > 0.5 for all).
CONCLUSIONS: Shoulder muscle strength for abduction and rotation measured with the Biodex dynamometer are reproducible and correlate with the strength assessment of the CS. Therefore, these isometric muscle strength tests can be further employed to investigate the effect of different shoulder joint pathology on muscle strength. These measurements consider a more comprehensive functionality of the rotator cuff than the single strength evaluation in abduction within the CS as both abduction and rotation are assessed. Potentially, this would allow for a more precise differentiation between the various outcomes of rotator cuff tears.

BACKGROUND: The aim of this study was to create a novel complication classification for osteosynthesis-related complications following angular stable plating of the proximal humerus subsuming the influence of these complications on clinical outcome in relation to fracture morphology and consequent revision strategies. A total of 1047 proximal humerus fractures with overall 193 osteosynthesis-associated complications (24.5%) were included. The following complication types could be clarified: complication Type 1 is defined by mild varus (<20°) or valgus displacement of the humeral head without resulting in a screw cutout through the humeral head cortex. Type 2a is defined by varus displacement (<20°) of the humeral head associated with screw cutout through the humeral head cortex. Type 2b complication is limited to displacement of the greater tuberosity, lesser tuberosity, or both tuberosities. Complication Type 2c is defined by severe varus dislocation (>20°) of the humeral head with screw cutout at the humeral head cortex. Complication Type 3 describes a displacement of the angular stable plate in the humeral shaft region with associated shaft-sided screw cutout, while the position of the humeral head remains static. Complication Type 4 is characterized by the occurrence of AVN with or without glenoidal affection (4a/b). Clinical outcome according to the constant score was mainly affected by type 2-4, leading to a deteriorated result. Depending on the type of complication, specific revision strategies can be considered. Additionally, more complex fracture patterns fostered the incidence of complications.

BACKGROUND: The best surgical management of displaced proximal humeral fractures remains a matter of considerable debate. This study presents mid-term functional outcome (median 4 years) after locking plate osteosynthesis for displaced proximal humeral fractures.
METHODS: Between February 2002 and December 2014 1031 patients with 1047 displaced proximal humeral fractures were treated by open reduction and locking plate fixation with the same implant and received consecutive prospective follow up at least 24 months after surgical treatment. Clinical follow-up consisted of Constant Murley score (CS), Disabilities of the Arm, Shoulder and Hand score (DASH), and Short Form 36 questionnaire (SF-36). Complete follow-up could be performed in 557 (53.2%) cases, with a mean follow-up of 4.0 ± 2.7 years.
RESULTS: Of 557 patients (67% women; mean age at time of osteosynthesis: 68.3 ± 15.5 years) absolute CS of all patients 4 ± 2.7 years after surgery was 68.4 ± 20.3 points. Normalized CS according to Katolik was 80.4 ± 23.8 points, and CS in percentage to the contralateral side (%CS) was 87.2 ± 27.9%. DASH score was at 23.8 ± 20.8 points. Osteosynthesis related complications (secondary displacement, screw cutout, avascular necrosis (n = 117 patients) were associated with lower functional scores (mean CS was 54.5 ± 19.0 p.; nCS 64.5 ± 22.9 p.;%CS 71.2 ± 25.0%; DASH score 31.9 ± 22.4 p.). The SF 36 was 66.5 points in the case cohort and a vitality mean of 69.4 points. Patients with a complication showed lower results (SF 36 56.7; vitality mean 64.9 points).
CONCLUSIONS: Overall, patients following locking plate osteosynthesis of displaced proximal humeral fractures showed good to moderate outcomes four years after surgery. Mid-term functional outcomes correlate significantly with those at 1 year postoperatively. Furthermore, there is a significant negative correlation of midterm functional outcome with the occurrence of complications.
METHODS: Level III, prospective nonconsecutive patients.

UNASSIGNED: The purpose was to report mid-term to long-term clinical outcomes in a multicentre series of patients who received stemless total shoulder arthroplasty (TSA). The hypothesis was that stemless TSA would be a safe and effective treatment with satisfactory clinical outcomes.
UNASSIGNED: Authors retrospectively reviewed records of 62 stemless TSAs implanted between March 2013 and December 2014. Six were excluded because they had fractures or muscular impairment, which left 56: primary osteoarthritis (n = 49), rheumatoid arthritis (n = 4), avascular necrosis (n = 1), or glenoid dysplasia (n = 2). Outcomes were absolute Constant Score (CS), age-/sex-adjusted CS, and the American Shoulder and Elbow Surgeons (ASES) score. Proportions of patients that achieved substantial clinical benefits for absolute CS and ASES scores were determined.
UNASSIGNED: Of the 56 patients, 8 (14%) died (unrelated to TSA), 5 (9%) were lost to follow-up, and 2 (4%) refused participation. One patient was reoperated for infection with implant removal (excluded from analysis), and one for periprosthetic fracture without implant removal. At 7.6 ± 0.5 years (range 6.8-9.3), the remaining 40 patients, aged 71.0 ± 8.5 years, achieved net improvements of 40.7 ± 15.8 (CS), 62%±23% (age-/sex-adjusted CS), and 59.7 ± 16.4 (ASES). Of patients with complete absolute CS (n = 37) and ASES score (n = 28), respectively, 33 (89%) and 27 (96%) achieved substantial clinical benefits.
UNASSIGNED: Stemless TSA yields improvements in functional outcomes at mid-term to long-term that exceed the substantial clinical benefits of the absolute CS and ASES score at a mean follow-up of 7.6 years. Although the findings of this study revealed low complications and revision rates, more studies are needed to confirm long-term benefits of stemless TSA.
UNASSIGNED: IV, case series.