Wedged Insoles for Management of Knee Osteoarthritis

University of Calgary

Status: Completed

Conditions: Knee Osteoarthritis

Treatments: Device: wedged insole

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT02067208

23731-01

Details and patient eligibility

About

Knee osteoarthritis (OA) is commonly treated using laterally wedged insoles. Although these insoles typically reduce knee abduction moments (KAM) - a variable associated with knee osteoarthritis - and thus are believed to be beneficial for OA management, recent research has indicated that in some cases lateral wedge insoles actually increase knee joint loads. In such cases, a medial wedge may be more appropriate.

The purpose of this study is to evaluate the influence of reduced KAMs on pain over 3-months for patients with knee OA. It is hypothesized that pain reduction will be directly related to KAM reduction.

Forty-six participants with knee OA will be recruited to participate. Each will undergo biomechanical gait analysis to determine the wedge type that most greatly reduces knee adduction moments. In addition, each participant will undergo a Dual Energy X-Ray Absorptiometry (DXA) scan to quantify adiposity. Finally, participants will complete a series of questionnaires to evaluate pain, function, physical activity, footwear comfort and injury history. Participants will be randomized into either a wait list control group (no insole) or experimental group (medial or lateral wedged insole), and monitored for 3 months.

Changes to pain, function, comfort and physical activity from baseline to 3 months will be assessed within the control and experimental groups. Regression analyses will be conducted on the experimental group to determine if a relationship exists between reduced KAMs and reduced pain over 3 months. Comparisons will also be made between the control and experimental groups.

Enrollment: 48 patients

Sex: All

Ages: 40 to 85 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Physician-diagnosed knee osteoarthritis (using American College of Rheumatology clinical and radiographic criteria)
• Kellgren-Lawrence grade 1, 2, 3 or 4
• Primary symptoms and disease location must be attributed to medial tibiofemoral compartment
• KOOS pain of 75 points or lower (where 0 is worst pain and 100 is no pain)

Exclusion criteria

• X-ray older than 2 years
• Viscosupplementation within past 6 months
• Cortisone injection in past 3 months
• Narcotic pain medication within past 3 months
• Use of knee unloading brace interventions in past 2 months
• Recent (past 6 months) knee or neuromuscular injury that could bias pain assessments or gait analysis results
• No KAM reduction with either lateral or medial wedge insole

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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48 participants in 2 patient groups

Waitlist Control

No Intervention group

Description:

A waitlist control condition, where the participant receives no insole for 3 months. During this 3 month period, the participant will continue to be monitored for outcome variables.

Experimental wedged insole

Experimental group

Description:

Either a medially wedged or laterally wedged footwear insole (whichever reduces knee joint mechanical loading more, as determined from subject-specific biomechanical tests), constructed using a 3D printer will be inserted into each participant's shoe. The participant will be asked to utilize this insole as much as possible throughout the day over the course of 3 months.

Treatment:

Device: wedged insole