A kinematic and electromyographic comparison of a Grammont-style reverse arthroplasty combined with a l'Episcopo transfer compared to a lateralized humeral component reverse for restoration of active external rotation.

PURPOSE: To assess kinematic and electromyographic findings of two designs of reverse total shoulder arthroplasty (RTSA). We tested two hypotheses: (H1) Grammont-style (RTSA) with l'Episcopo tendon transfer gains similar postoperative kinematic findings of a lateralized humeral component RTSA without a tendon transfer; (H2) RTSA with lateralized humeral component induces earlier shoulder muscle activation during shoulder motion compared with standard Grammont prosthesis with l'Episcopo transfer. METHODS: Twenty-five patients with a cuff tear arthropathy, pseudoparalysis, and a positive dropping sign were sequentially included. A Grammont-style RTSA with a l'Episcopo tendon transfer was implanted in 13 patients (medialized humerus and transfer group) and an on-lay curved-stem RTSA in 12 (lateralized humerus group). Constant score; the disabilities of the arm, shoulder, and hand (DASH) score; and active shoulder range of motion (flexion, abduction, external rotation, and internal rotation) were measured pre- and postoperatively. Upper limb kinematic and surface electromyography (EMG) (anterior and posterior deltoid; upper, middle, and lower trapezius; and the upper and lower latissimus dorsi muscles) were recorded during active range of motion. RESULTS: At > 24 months of follow-up, the Constant and DASH scores and active shoulder range of motion improved in both groups (p < 0.0001). Internal rotation was significantly higher in the lateralized humerus group than in the medialized humerus and transfer group (p = 0.004). The dropping sign was found in 0/12 patients in the lateralized humerus group and in 5/13 patients in the medialized humerus and transfer group (p < 0.001). Kinematic findings were similar between groups (p = 0.286). A pattern of earlier muscle activation in the lateralized humerus group was found as compared to the transfer group as follows: (i) posterior deltoid during external rotation (p = 0.004); (ii) upper latissimus dorsi and middle and lower trapezius during flexion (p = 0.004, p = 0.005, and p = 0.042, respectively); (iii) lower latissimus dorsi during abduction (p = 0.016). CONCLUSION: RTSA with a lateralized humeral component provided similar active external rotation restoration to a Grammont-style RTSA with a l'Episcopo procedure in patients with a dropping sign. The posterior deltoid muscle underwent earlier activation during active external rotation in the lateralized humerus RTSA group as compared to the tendon transfer group. Our findings demonstrated the H1 and only partially demonstrated the H2 of the study.

Assessment of anatomical and reverse total shoulder arthroplasty with the scapula-weighted Constant-Murley score.

AIM OF THE STUDY: To evaluate total (TSA) and reverse total shoulder arthroplasty (RTSA) using the Constant-Murley score (CMS) and the scapula-weighted (SW) CMS, an integrated outcome measure that takes into account the compensatory movements of the scapula. METHODS: Twenty-five consecutive patients, 12 with TSA and 13 with RTSA, underwent kinematic analysis before and after shoulder replacement. Measurements included flexion (FLEX) and abduction (ABD) for the humerus and Protraction-Retraction (PR-RE), Medio-Lateral rotation (ME-LA), and Posterior-Anterior tilting (P-A) for the scapula. They were recorded at baseline (T0) and at six (T1) and 12 months (T2). Reference data were obtained from 31 control shoulders. RESULTS: At T1, differences in CMS and SW-CMS were not significant in either group, whereas values at T2 were significantly lower in RTSA patients (p = 0.310 and p = 0.327, respectively). In TSA shoulders, the compensatory scapular movements in FLEX were all reduced from T0 to T2, whereas P-A was increased in ABD. In RTSA patients, the compensatory scapular movements in FLEX showed a general reduction at T1, with an increase in P-A at T2, whereas in ABD, all increased at T1 and decreased at T2 except for P-A, which did not decrease. DISCUSSION: The SW-CMS showed that the physiological scapulothoracic motion was not restored in TSA and RTSA patients; it may be used as a reference for the gradual progression of deltoid and scapular muscle rehabilitation. CONCLUSIONS: The worse CMS and SW-CMS scores found in RTSA patients at six months may be due to the biomechanics of the reverse prosthesis and to the weakness of deltoid and periscapular muscles.

Shoulder Rehabilitation Exercises With Kinematic Biofeedback After Arthroscopic Rotator Cuff Repair: Protocol for a New Integrated Rehabilitation Program.

BACKGROUND: The recovery of scapular and humeral physiological kinematic parameters, as well as the sensorimotor control of movement, plays a primary role in the rehabilitation process after arthroscopic rotator cuff repair. A highly customized rehabilitation approach is required to achieve this aim. Biofeedback can be a useful tool, but there is poor evidence of its application in the rehabilitation after arthroscopic rotator cuff tear repair. OBJECTIVE: The aim of this paper is to outline an innovative exercise-based rehabilitation program exploiting visual biofeedback for the recovery of patients arthroscopically treated for rotator cuff repair. METHODS: For establishment of the innovative program, a multidisciplinary team involving experts in shoulder surgery, rehabilitation medicine, physical therapy, and biomedical and clinical engineering was formed. Starting from a conventional rehabilitation program, the team selected a set of exercises to be integrated with a biofeedback tool, named the INAIL (National Institute for Insurance against Accidents at Work) Shoulder and Elbow Outpatient program (ISEO program). ISEO is a motion analysis system based on inertial wearable sensors positioned over the thorax, scapula, humerus, and forearm. ISEO can return a visual biofeedback of humerus and scapula angles over time or of the scapula-humeral coordination, with possible overlap of patient-specific or asymptomatic reference values. A set of 12 progressive exercises was defined, divided into four groups based on humerus and scapula movements. Each group comprises 2-4 of the 12 exercises with an increasing level of complexity. Exercises can require the use of a ball, stick, rubber band, and/or towel. For each exercise, we present the starting position of the patient, the modality of execution, and the target position, together with notes about the critical factors to observe. The type of visual biofeedback to adopt is specified, such as the coordination between angles or the variation of a single angle over time. To guide the therapist in customizing the patient's rehabilitation program, a list of operative guidelines is provided. RESULTS: We describe various applications of the ISEO exercise program in terms of frequency and intensity. CONCLUSIONS: An innovative rehabilitation program to restore scapular and humeral kinematics after rotator cuff repair based on kinematic biofeedback is presented. Biofeedback is expected to increase patient awareness and self-correction under therapist supervision. Randomized controlled trials are needed to investigate the potential effect of the exercise-based biofeedback in comparison with conventional rehabilitation programs. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/35757.

Motion analysis of the shoulder in adults: kinematics and electromyography for the clinical practice.

In this paper, the principal aspects of kinematic and electromyographic (EMG) analysis of the shoulder and their potential for the every-day clinical practice are described. The text reports a brief description of standard recommendations for movement assessment, an overview of the main quantitative motion analysis protocols and a description of the most commonly investigated scapulothoracic muscles. To assess the possibility of using these protocols for clinical applications, reliability and repeatability of kinematic and EMG measures were investigated and reference data for scapulohumeral joint kinematics were provided. The last part of the manuscript reports the integration of the quantitative analysis of scapula dyskinesis within the widely accepted Constant-Murley clinical score. In addition, examples of assessment of muscles activity and recruitment patterns are discussed since they are crucial for the clinical evaluation of common shoulder pathologies.

The Constant score and the assessment of scapula dyskinesis: Proposal and assessment of an integrated outcome measure.

The Constant-Murley score (CMS) is a popular measure of shoulder function. However, its ability to monitor the evolution of patients during rehabilitation after rotator-cuff repair is controversial. Moreover, CMS does not account for possible alterations in the scapulo-humeral coordination (SHC, scapula dyskinesis), which are apparent in variety of shoulder pathologies. To address these issues, a new formulation of CMS was firstly proposed, which rates the "affected-to-controlateral side difference in SHC" of a patient with respect to reference values of asymptomatic controls (Scapula-Weighted CMS). Then, 32 patients (53±9year-old) were evaluated with CMS and SW-CMS at 45, 70, 90-day and >6-month after rotator-cuff repair, to test three hypotheses: (1) CMS and SW-CMS are largely responsive to change; (2) accounting (SW-CMS) or not (CMS) for scapula dyskinesis leads to statistically different scores and SW-CMS cannot be predicted from CMS without clinically relevant differences; (3) 90% of patients recover a side-to-side SHC similar to asymptomatic controls at 90days. Results supported hypotheses 1 and 2. On the contrary (hypothesis 3), only 10% of patients recovered for SHC alterations at 90days, and 50% at follow-up. These findings support the use of SW-CMS and the importance of treating scapula dyskinesis after rotator-cuff repair.