Simulated Ankle Equinus Affects Knee Kinematics during Gait. Issue 1 (February 2016)

• Record Type: Journal Article
• Authors: Drefus, Lisa C.; Hafer, Jocelyn F.; Scher, David M.
• Is Part Of: HSS journal. Volume 12:Issue 1(2016)
• Page Start: 39
• Page End: 43
• Publication Date: 2016-02
• Subjects: equinus -- gait -- knee kinematics -- cerebral palsy -- knee flexion -- gait compensations; Musculoskeletal system -- Surgery -- Periodicals; Orthopedic surgery -- Periodicals; Musculoskeletal System -- surgery -- Periodicals; Orthopedic Procedures -- Periodicals; Orthopédie -- Périodiques; Appareil locomoteur -- Maladies -- Périodiques; Appareil locomoteur -- Maladies -- Patients -- Réadaptation -- Périodiques; 617.47005
• DOI: 10.1007/s11420-015-9474-4
• Languages: English
• ISSNs: 1556-3316

Abstract

Background: It is critical to distinguish gait compensations from true abnormalities when planning interventions to improve gait in individuals with neuromuscular disorders. Questions/Purposes: The aim of this study was to determine the effect of isolated ankle equinus on knee kinematics during the initial contact phase of gait. Methods: Ten healthy subjects (29 + 4.3 years) participated, and testing occurred in a motion analysis laboratory. This cross-sectional study investigated five gait conditions in each subject: shoe alone, shoe with unilateral ankle foot orthosis locked at neutral, 10°, 20°, and 30° of fixed ankle plantar flexion. Gait kinematics were recorded and calculated with 3D motion analysis. The difference between the shoe and each brace condition was analyzed by repeated-measures ANOVA. The primary outcome was knee flexion at initial contact. Results: With greater than 10° simulated ankle equinus, the primary gait compensation pattern was increased knee flexion at initial contact. A significant degree of knee flexion occurred ranging from 7° to 22°. Conclusion: Our data suggests that observed knee flexion at initial contact may be a compensation pattern in individuals with >10° ankle equinus. However, in individuals with ≤10° ankle equinus, observed knee flexion may represent a true gait deviation. This has clinical significance in the realm of cerebral palsy for treatment planning to improve gait.