Objective Gait Analysis Using a Single-Point Wearable Sensor to Assess Lumbar Spine Patients Pre- and Postoperatively

Abstract

Background: Outcome measurement in lumbar surgery is traditionally performed using patient questionnaires that may be limited by subjectivity. Objective gait analysis may supplement patient assessment but must be clinically viable. We assessed gait metrics in lumbar spine patients pre- and postoperatively using a small and lightweight wearable sensor. Methods: This was a prospective observational study with intervention including 12 patients undergoing lumbar spine surgery and 24 healthy controls matched based on age and sex. All the subjects underwent gait analysis using the single-point wearable MetaMotionC sensor. The lumbar spine patients also completed traditional patient questionnaires including the Oswestry Disability Index (ODI). Results: The ODI score significantly improved in the patients from the baseline to six weeks postoperatively (42.4 to 22.8; p = 0.01). Simultaneously, the patients demonstrated significant improvements in gait asymmetry (asymmetry in step length, swing time, single support time, and double support time, by 17.4–60.3%; p ≤ 0.039) and variability (variability in gait velocity, step time, step length, stance time, swing time, single support time, and double support time, by 21.0–65.8%; p ≤ 0.023). After surgery, changes in most spatiotemporal (gait velocity, step length, stance time, swing time, and single limb support time) and asymmetry (asymmetry in step time, stance time, swing time, and single limb support time) metrics correlated strongly (magnitude of r = 0.581–0.914) and significantly (p ≤ 0.037) with changes in the ODI. Conclusions: Gait analysis using a single-point wearable sensor can demonstrate objective evidence of recovery in lumbar spine patients after surgery. This may be used as a routine pre- and postoperative assessment during scheduled visits to the clinic.