Anterior Heel Wedge to Treat Flexion Contracture After Total Knee Arthroplasty

NCT07620145 | Completed Early Phase 1

• 1 other identifier: 22-1206
• Study Type: interventional
• Target: 8
• Locations: 1 country
• Sites: 1

Brief Summary

Total knee arthroplasty (TKA) remains the only treatment for end-stage knee osteoarthritis, whereby the diseased ends of the bones comprising the knee joint are removed and replaced with prosthetic joint components. Approximately 500,000 of these procedures are performed annually in the United States. Despite an otherwise successful procedure and post-operative rehabilitation process, about 5% of all individuals will develop a flexion contracture after TKA. Flexion contracture limits the knee joint range of motion, which has negative impacts on activities of daily living and health-related quality of life. Standard of care treatment for resolving flexion contracture requires more surgery or, at minimum, more exposure to anesthesia to manipulate the joint and improve range of motion. The investigators have developed a non-invasive means for resolving flexion contracture, The investigators propose fixing a wedge to the sole of the patient's shoe such that the taller end of the wedge is located near the toes and the shorter end is closer to the heel. Biomechanically, this forces the individual to make ground contact during walking closer to the heel rather than the toes (which is typically observed in patients with flexion contracture). By forcing ground contact closer to the heel, patients gradually force their knee to extend (straighten) over time and resolve the flexion contracture. The aim of this pilot investigation is to test the hypothesis that the anterior wedge worn on the shoe during all walking activities for 4 weeks will reduce the severity of the flexion contracture in patients after TKA.

Conditions

Knee Flexion Contracture; Total Knee Arthroplasty (TKA)

Keywords

walking; knee; range of motion

Outcome Measures

Primary Outcomes (1)

• Gait biomechanics

  Participants will walk over level ground at a self-selected pace and one equivalent to average older adult walking speed.

  From enrollment to the end of treatment at 4 weeks

Secondary Outcomes (4)

• Patient-reported outcomes

  From baseline to the end of the intervention at 4 weeks

• Patient-reported outcomes

  From baseline to the end of the intervention at 4 weeks

• Patient-reported outcomes

  From baseline to the end of the intervention at 4 weeks

• Patient-reported outcomes

  From baseline to the end of the intervention at 4 weeks

Study Arms (1)

Orthotic

EXPERIMENTAL

Participants enrolled in this arm wear an anterior heel wedge, in the form of a shoe orthotic, to improve walking and reduce knee flexion contracture. The wedge is worn continuously on the shoe for 1 month.

Device: Anterior heel wedge

Interventions

Anterior heel wedge DEVICE

A continuously-worn shoe anterior heel wedge that fits on the under surface of the shoe just under the toe box. When worn during walking, the anterior heel wedge may help to increase knee joint range of motion and reduce knee flexion contracture in patients after total knee arthroplasty.

Orthotic

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• over the age of 18 years
• underwent primary, unilateral TKA and approved for participation by surgeon
• present with flexion contracture in the operative limb (5 degrees or greater at least 3 months after surgery)
• body mass index \<40kg/m\^2

You may not qualify if:

• underwent revision TKA
• underwent bilateral TKA
• require use of assistive device to walk
• inability to consistently comprehend and repeat back directions, including for reasons of not understanding/speaking English
• current smoker

Sponsors & Collaborators

• University of North Carolina, Charlotte: lead

Study Sites (1)

UNC Charlotte

Charlotte, North Carolina, 28269, United States

Location

Related Publications (1)

• Sappey-Marinier E, Fernandez A, Shatrov J, Batailler C, Servien E, Huten D, Lustig S. Management of fixed flexion contracture in primary total knee arthroplasty: recent systematic review. SICOT J. 2024;10:11. doi: 10.1051/sicotj/2024007. Epub 2024 Mar 26.

  PMID: 38530205 RESULT

Study Design

• Study Type: interventional
• Phase: early phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: December 19, 2024
• First Posted: June 2, 2026
• Study Start: March 16, 2023
• Primary Completion: December 31, 2025
• Study Completion: December 31, 2025
• Last Updated: June 2, 2026

Record last verified: 2026-05

Locations

US (1)