The efficacy of a lateral wedge insole for painful medial knee osteoarthritis after prescreening : a randomized clinical trial

Felson, DT; Parkes, M; Carter, S; Liu, A; Callaghan, MJ; Hodgson, R; Bowes, M; Jones, RK

Abstract

OBJECTIVE:
Lateral wedge shoe insoles decrease medial knee loading, but trials have shown no effect on pain in medial knee osteoarthritis (OA). However, insoles' loading effects are inconsistent, and they can increase patellofemoral loading. We hypothesized that insoles would reduce pain in preselected patients.


METHODS:
In persons with painful medial knee OA, we excluded those with patellofemoral OA and those with pain <4/10. We further excluded participants who, in a gait laboratory using lateral wedges, did not show at least a 2% reduction in knee adduction moment (KAM) compared with their shoes and a neutral insole. We then randomized subjects to lateral wedge vs. neutral insole for 8 week periods separated by an 8 week washout. Primary outcome was knee pain over the past week (0-10) and secondary outcomes nominated activity pain and KOOS pain. We carried out mixed model analyses adjusted for baseline pain.


RESULTS:
Of 83 participants, 21 (25%) were excluded because of insufficient reduction in KAM. Of 62 included, mean age was 64.2 years (SD 9.1); 37.1% were women. Lateral wedge insoles produced a greater reduction in knee pain than neutral insoles (difference 0.7 on 0-10 scale; 95%CI 0.1, 1.2; p = 0.02). Secondary outcomes showed mixed findings.


CONCLUSIONS:
In persons prescreened to eliminate those with patellofemoral OA and biomechanical non-responders, lateral wedge insoles reduced knee pain, but the effect of treatment was small and is likely of clinical significance in only a minority of patients. Targeting patients may identify those who respond to this treatment.

Citation

Felson, D., Parkes, M., Carter, S., Liu, A., Callaghan, M., Hodgson, R., …Jones, R. (2019). The efficacy of a lateral wedge insole for painful medial knee osteoarthritis after prescreening : a randomized clinical trial. Arthritis and Rheumatology, 71(6), 908-915. https://doi.org/10.1002/art.40808

• Journal Article Type: Article
• Acceptance Date: Dec 13, 2018
• Online Publication Date: Jan 7, 2019
• Publication Date: Jun 1, 2019
• Deposit Date: Jan 10, 2019
• Publicly Available Date: Jan 7, 2020
• Journal: Arthritis & Rheumatology
• Print ISSN: 2326-5191
• Publisher: Wiley
• Volume: 71
• Issue: 6
• Pages: 908-915
• DOI: https://doi.org/10.1002/art.40808
• Publisher URL: https://doi.org/10.1002/art.40808
• Related Public URLs: https://onlinelibrary.wiley.com/toc/23265205/0/ja
• Additional Information: Projects : Manchester BRU; Grant Number: AR‐47785