Shoe Lifts for Leg Length Discrepancy in Adults With Common Painful Musculoskeletal Conditions: A Systematic Review of the Literature

Abstract

Objective: To determine whether shoe lifts effectively treat leg length discrepancy (LLD)-associated morbidities in adults with common painful musculoskeletal conditions.

Data sources: Trip database, Cochrane Central Register of Controlled Trials database, PubMed database, Physiotherapy Evidence Database, and National Guideline Clearinghouse database. The search was performed in September 2017, was limited to English only, and had no time constraints.

Study selection: Two reviewers independently determined study eligibility. Inclusion criteria were (1) participants ≥18 years old with musculoskeletal-related complaints and LLD; (2) a shoe lift intervention was used; and (3) the study reported on pain, function, range of motion, patient satisfaction, quality of life, or adverse events. Randomized controlled trials (RCTs) and controlled intervention, cohort, before-and-after, case series, and case report studies were included. Three-hundred and nineteen articles were screened, and 9 guidelines were reviewed.

Data extraction: We extracted data pertaining to participant demographic characteristics, study setting, recruitment, randomization, method of LLD measurement, shoe lift characteristics, treatment duration, and outcome measures. We included 10 studies, including 1 RCT.

Data synthesis: LLD was associated with low back pain, scoliosis, and osteoarthritis of the hip and knee. Description of LLD correction strategy was often inadequate. Study quality was very low or poor. In non-RCT studies reporting on the proportion of participants who improved with a shoe lift, 88%±3% of 349 participants treated had partial or complete pain relief (effect size range, 66.7%-100%). All 22 RCT participants receiving treatment experienced pain relief (mean pain reduction, 27±9mm on a 150-mm visual analog scale). Two of 9 guidelines recommended shoe lift use based on consensus and were of moderate-to-high quality.

Conclusions: There is low-quality evidence that shoe lifts reduce pain and improve function in patients with LLD and common painful musculoskeletal conditions. High-quality research evaluating a threshold LLD to correct and a strategy to do so is necessary. Developing an appropriate comparison group to test clinically relevant outcome measures would make a valuable contribution in this regard.

Keywords: Leg length inequality; Rehabilitation; Review, systematic.