Maintenance Notice

Due to necessary scheduled maintenance, the JMIR Publications website will be unavailable from Wednesday, July 01, 2020 at 8:00 PM to 10:00 PM EST. We apologize in advance for any inconvenience this may cause you.

Who will be affected?

Accepted for/Published in: JMIR Rehabilitation and Assistive Technologies

Date Submitted: Jul 9, 2025
Open Peer Review Period: Jul 9, 2025 - Sep 3, 2025
Date Accepted: Jan 13, 2026
(closed for review but you can still tweet)

The final, peer-reviewed published version of this preprint can be found here:

Evaluation of a Stretching Forearm Sleeve for Lateral Epicondylitis: Repeated Measures Study

Ríos Rincón AM, Guptill C, Tran A, Kamran R, Alshammari S, Miguel Cruz A

Evaluation of a Stretching Forearm Sleeve for Lateral Epicondylitis: Repeated Measures Study

JMIR Rehabil Assist Technol 2026;13:e80400

DOI: 10.2196/80400

PMID: 41780923

Evaluation of a Stretching Forearm Sleeve for Lateral Epicondylitis: A Repeated Measures Design

  • Adriana M. Ríos Rincón; 
  • Christine Guptill; 
  • Ann Tran; 
  • Rija Kamran; 
  • Salamah Alshammari; 
  • Antonio Miguel Cruz

ABSTRACT

Background:

Lateral epicondylitis (LE) is a condition that impairs daily activities due to pain exacerbated by wrist and hand movements. The ArmLock Sleeve is a novel, non-surgical intervention to stretch the wrist extensor muscles by maintaining the elbow in extension, forearm in pronation, and wrist and fingers in flexion.

Objective:

This study aimed to assess the effectiveness of sustained tension provided by the ArmLock Sleeve on pain and functional outcomes in adults with LE. This novel device supports the forearm by aligning the elbow in extension, the forearm in pronation, and the wrist in flexion, while keeping the metacarpophalangeal and interphalangeal joints of fingers II–V flexed.

Methods:

A within-subjects repeated measures design was used to assess outcomes at baseline, weeks 6, and 12. Nineteen participants wore the device at home for 30 minutes daily over 12 weeks. Outcome measures were administered by research assistants and included pain intensity, pain-free grip strength, pressure pain threshold, pain during resisted wrist extension, and composite extensibility of wrist and finger extensors. Repeated measures one-way ANOVA and Friedman tests were conducted (α = 0.05), followed by post hoc comparisons (α = 0.017, Bonferroni correction).

Results:

Significant improvements were observed in six of seven (85.7%) outcome variables, including increased muscle extensibility, enhanced grip strength, and reduced pain intensity. Participants reported decreased pain and functional disability in a self-reported questionnaire.

Conclusions:

Wearing the device daily for 12 weeks led to significant improvements in extensibility, grip strength, and pain reduction. Participants also reported decreased pain and disability. These results suggest that the ArmLock sleeve may support symptom relief and functional gains in individuals with LE. Larger, controlled studies are needed to confirm its effectiveness. Clinical Trial: ISRCTN13309889 https://www.isrctn.com/ISRCTN13309889


 Citation

Please cite as:

Ríos Rincón AM, Guptill C, Tran A, Kamran R, Alshammari S, Miguel Cruz A

Evaluation of a Stretching Forearm Sleeve for Lateral Epicondylitis: Repeated Measures Study

JMIR Rehabil Assist Technol 2026;13:e80400

DOI: 10.2196/80400

PMID: 41780923

Download PDF


Request queued. Please wait while the file is being generated. It may take some time.

© The authors. All rights reserved. This is a privileged document currently under peer-review/community review (or an accepted/rejected manuscript). Authors have provided JMIR Publications with an exclusive license to publish this preprint on it's website for review and ahead-of-print citation purposes only. While the final peer-reviewed paper may be licensed under a cc-by license on publication, at this stage authors and publisher expressively prohibit redistribution of this draft paper other than for review purposes.