EMG Biofeedback and NMES of Deltoid in Patients With rTSA

Not Applicable

Recruiting

• Conditions: Reverse Shoulder Replacement

• Registration Number: NCT06873022
• Lead Sponsor: National Taiwan University Hospital

Brief Summary

The effect of NMES and surface electromyography (sEMG) biofeedback on the deltoid and associated scapular muscles in scapular kinematics and muscle activation in individual post rTSA

Detailed Description

Reverse total shoulder arthroplasty (rTSA) has been the optimal treatment for massive irreparable rotator cuff tears and cuff tear arthropathy. Since scapular kinematics alteration was associated with shoulder disorders, scapular kinematics had been characterized in individuals post rTSA with more upward rotation, external rotation, and posterior tilt of the scapula. In addition, the average scapulohumeral rhythm ranged from 1.1 to 1.6, indicating lower glenohumeral joint movements and higher scapulothoracic movements. It supposed that more scapula upward rotation without adequate humeral elevation can result in the scapula notching. Therefore, strategy to decrease scapular movement or increase humeral movements during arm movements may prevent scapula notching. To compensate for rotator cuff deficiency, the deltoid muscle plays a crucial role post rTSA. Enhancing deltoid function can be accomplished through the use of biofeedback or neuromuscular electrical stimulation (NMES). However, the effect of NMES and surface electromyography (sEMG) biofeedback on the deltoid and associated scapular muscles in scapular kinematics, muscle activation, and muscle balance ratio in individual post rTSA remained unclear. Therefore, the objectives in this study would to (1) determine the immediate effects of NMES with EMG biofeedback to deltoid (D) on the muscle activation of upper trapezius (UT), lower Trapezius (LT) and serratus Anterior (SA) as well as the scapular kinematics (upward/downward rotation, external/internal rotation, anterior/posterior tilting) (2) evaluate the immediate effects of NMES with EMG biofeedback on the muscle balance ratios (D/UT, D/LT, D/SA) and the scapulohumeral rhythm (SHR) during arm elevation in the scapular plane at different range of motion.

Study Timeline

• Status Verified: 2024-05
• Study First Submitted: 2025-02-17
• Study First Submitted QC: 2025-03-06
• Last Update Submitted: 2025-03-06
• Study First Posted: 2025-03-12
• Last Update Posted: 2025-03-12
• Study Start: 2025-03-15
• Primary Completion: 2025-05-20
• Study Completion: 2025-05-20

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 34

Inclusion Criteria

• (1) age between 20 to 85 years old
• (2) undergoing primary reverse shoulder arthroplasty
• (3) shoulder abduction in scapular plane above 90 degrees
• (4) above 3 months following rTSA

Exclusion Criteria

• (1) a history of other shoulder surgery on the rTSA shoulder
• (2) a revision rTSA
• (3) a surgery shoulder muscle tendon transfer
• (4) neuromuscular diseases
• (5) cognitive disorders
• (6) contraindications for NMES

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: CROSSOVER

Primary Outcome Measures

Name	Time	Method
Muscle activation	before intervention (baseline) and through intervention completion, an average 15 minutes in each intervention (sEMG biofeedback or NMES)	Muscle activation The muscle activation of upper trapezius, lower trapezius, serrates anterior, and deltoid were collected during arm elevation task by sEMG at baseline, post- sEMG biofeedback, and post- NMES. Muscle activation was analyzed based on 0°-30°, 30°-60°, and 60°-90° during arm elevation and lowering. The sEMG data was calculated using the root mean square (RMS) based on average of middle three from five trials. The MVIC of UT, LT, SA, and D were used to normalize the sEMG data.
Scapular kinematics	before intervention (baseline) and through intervention completion, an average 15 minutes in each intervention (sEMG biofeedback or NMES)	Scapular kinematics The scapular kinematics during arm elevation task was captured using an electromagnetic motion analysis system. The three scapula orientations were described using the Euler angle sequence with an X-axis for scapular posterior/anterior tilt, Y-axis for scapular upward/downward rotation, and Z-axis for scapular internal/external rotation. The average of middle three from five trials on scapular kinematics were analyzed at 30°, 60°, and 90° arm elevation and lowering.

Secondary Outcome Measures

Name	Time	Method
Muscle balance ratios	before intervention (baseline) and through intervention completion, an average 15 minutes in each intervention (sEMG biofeedback or NMES)	Muscle balance ratios The muscle balance ratios of D/UT, D/LT, and D/SA were calculated based on average of middle three from five trials at the phases of 0°-30°, 30°-60°, and 60°-90° during arm elevation and lowering phase.
Scapulohumeral rhythm	before intervention (baseline) and through intervention completion, an average 15 minutes in each intervention (sEMG biofeedback or NMES)	Scapulohumeral rhythm The scapulohumeral rhythm data was collected by humeral elevation relative to scapular upward rotation at the phases of 30°, 60°, and 90° arm elevation and lowering in scapular plane. The data was based on average of middle three from five trials.

Trial Locations

Locations (1)

National Taiwan University of school and graduate of physical therapy of Performance Analysis Laboratory; 🇨🇳 Taipei City, Zhongzheng Dist., Taiwan