EMG Biofeedback and NMES of Deltoid in Patients With rTSA

Electromyography Biofeedback and Neuromuscular Electrical Stimulation of Deltoid in Patients With Reverse Total Shoulder Arthroplasty

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

Study Overview

• Status: Recruiting
• Conditions: Reverse Shoulder Replacement
• Intervention / Treatment: Device: biofeedback; Device: neuromuscular electrical stimulation

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 Type: Interventional
• Enrollment (Estimated): 34
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: YANG-TING CHIEN; Phone Number: +886980602820; Email: yangting890218@gmail.com
• Study Contact Backup: Name: Jiu-Jenq Lin, Ph.D; Phone Number: +8862-3366-8126; Email: jiujlin@ntu.edu.tw

Study Locations

• Taiwan
  • Zhongzheng Dist.
    • Taipei City, Zhongzheng Dist., Taiwan, 100
      • Recruiting
      • National Taiwan University of school and graduate of physical therapy of Performance Analysis Laboratory
      • Contact: YANG-TING CHIEN; Phone Number: +886980602820; Email: yangting890218@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

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 Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: biofeedback; sEMG biofeedback: Subjects were instructed to monitor the sEMG signals of the D/UT balances ratio on the screen and maintain the D/UT balances ratio above the threshold during arm elevation and lowering. The threshold was set at 1 standard deviation of the ratio average at baseline (before intervention).	Device: biofeedback; sEMG biofeedback: Subjects were instructed to monitor the sEMG signals of the D/UT balances ratio on the screen and maintain the D/UT balances ratio above the threshold during arm elevation and lowering. The threshold was set at 1 standard deviation of the ratio average at baseline (before intervention).
Experimental: neuromuscular electrical stimulation; NMES: Two electrode pads were placed on the anterior, middle, and posterior deltoid boundary lines and at a distance of 1cm distal to the lateral margin of the acromion. The operator palpated the deltoid muscle contraction and asked the subjects to perform arm elevation task with NMES. (frequency of 35 Hz and a duration of 250 microseconds.) A verbal cue was given during both th A verbal cue was given during both the sEMG biofeedback and NMES interventions: "Lengthen your arm as if you want to touch the ground, the scapula keeps in the neutral position, and then elevate your arm." Each intervention consisted of 3 sets of 10 repetitions per set, with a 1-minute rest between sets.	Device: neuromuscular electrical stimulation; NMES: Two electrode pads were placed on the anterior, middle, and posterior deltoid boundary lines and at a distance of 1cm distal to the lateral margin of the acromion. The operator palpated the deltoid muscle contraction and asked the subjects to perform arm elevation task with NMES. (frequency of 35 Hz and a duration of 250 microseconds.) A verbal cue was given during both th A verbal cue was given during both the sEMG biofeedback and NMES interventions: "Lengthen your arm as if you want to touch the ground, the scapula keeps in the neutral position, and then elevate your arm." Each intervention consisted of 3 sets of 10 repetitions per set, with a 1-minute rest between sets.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle activation	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.	before intervention (baseline) and through intervention completion, an average 15 minutes in each intervention (sEMG biofeedback or NMES)
Scapular kinematics	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.	before intervention (baseline) and through intervention completion, an average 15 minutes in each intervention (sEMG biofeedback or NMES)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle balance ratios	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.	before intervention (baseline) and through intervention completion, an average 15 minutes in each intervention (sEMG biofeedback or NMES)
Scapulohumeral rhythm	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.	before intervention (baseline) and through intervention completion, an average 15 minutes in each intervention (sEMG biofeedback or NMES)

Collaborators and Investigators

• Sponsor: National Taiwan University Hospital
• Investigators: Study Chair: Jiu-Jenq Lin, Ph.D, School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University, Taipei, Taiwan

Study record dates

Study Major Dates

• Study Start (Estimated): March 15, 2025
• Primary Completion (Estimated): May 20, 2025
• Study Completion (Estimated): May 20, 2025

Study Registration Dates

• First Submitted: February 17, 2025
• First Submitted That Met QC Criteria: March 6, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 6, 2025
• Last Verified: May 1, 2024

More Information

Terms related to this study

• Keywords: biofeedback; neuromuscular electrical stimulation; reverse total shoulder arthroplasty; surface electromyography; scapulohumeral rhythm
• Other Study ID Numbers: 202403141DINE

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No