Comparative gait analysis of ankle arthrodesis and arthroplasty: initial findings of a prospective study.
BACKGROUND
Little is known about functional outcomes of ankle arthroplasty compared with arthrodesis. This study compared pre-surgical and post-surgical gait measures in both patient groups.


METHODS
Eighteen patients with end-stage ankle arthritis participated in an ongoing longitudinal study (pre-surgery, 12 months post-surgery) involving gait analysis, assessment of pain and physical function. Outcome measures included temporal-distance, kinematic and kinetic data, the Short Form 36 (SF-36) body pain score, and average daily step count. A mixed effects linear model was used to detect effects of surgical group (arthrodesis and arthroplasty, n = 9 each) with walking speed as a covariate (α = 0.05).


RESULTS
Both groups were similar in demographics and anthropometrics. Followup time was the same for each group. There were no complications in either group. Pain decreased (p < 0.001) and gait function improved (gait velocity, p = 0.02; stride length, p = 0.035) in both groups. Neither group increased average daily step count. Joint range of motion (ROM) differences were observed between groups after surgery (increased hip ROM in arthrodesis, p = 0.001; increased ankle ROM in arthroplasty, p = 0.036). Peak plantar flexor moment increased in arthrodesis patients and decreased in arthroplasty patients (p = 0.042).


CONCLUSIONS
Initial findings of this ongoing clinical study indicate pain reduction and improved gait function 12 months after surgery for both treatments. Arthroplasty appears to regain more natural ankle joint function, with increased ROM. Long-term follow up should may reveal more clinically meaningful differences.
VA Puget Sound, Center of Excellence for Limb Loss Prevention and Prosthetic Engineering, Seattle, WA 98108, USA. mehahn@uw.edu
Michael E
ME
Hahn
Elise S
ES
Wright
Ava D
AD
Segal
Michael S
MS
Orendurff
William R
WR
Ledoux
Bruce J
BJ
Sangeorzan
D000843:Ankle Joint / Q000503:physiopathology / Q000601:surgery*; D001168:Arthritis / Q000503:physiopathology / Q000601:surgery; D001174:Arthrodesis; D058737:Arthroplasty, Replacement, Ankle; D001696:Biomechanical Phenomena; D005260:Female; D005684:Gait / Q000502:physiology*; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D007719:Knee Joint / Q000502:physiology; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology