Accelerometry Data Delineate Phases of Recovery and Supplement Patient-Reported Outcome Measures Following Lumbar Laminectomy.

Background: Patient-reported outcome measures (PROMs) are traditionally used to track recovery of patients after spine surgery. Wearable accelerometers have adjunctive value because of the continuous, granular, and objective data they provide. We conducted a prospective study of lumbar laminectomy patients to determine if time-series data from wearable accelerometers could delineate phases of recovery and compare accelerometry data to PROMs during recovery tracking.

Methods: Patients with lumbar stenosis for whom lumbar laminectomy was indicated were prospectively recruited. Subjects wore accelerometers that recorded their daily step counts from at least 1 week preoperatively to 6 months postoperatively. Subjects completed the Oswestry Disability Index and the 12-Item Short Form Health Survey preoperatively and at 2 weeks, 1 month, 3 months, and 6 months postoperatively. Daily aggregate median steps and individual visit-specific median steps were calculated. The Pruned Linear Exact Time method was used to segment aggregate median steps into distinct phases. Associations between visit-specific median steps and PROMs were identified using Spearman rank correlation.

Results: Segmentation analysis revealed 3 distinct postoperative phases: step counts rapidly increased for the first 40 days postoperatively (acute healing), then gained more slowly for the next 90 days (recovery), and finally plateaued at preoperative levels (stabilization). Visit-specific median steps were significantly correlated with PROMs throughout the postoperative period. PROMs significantly exceeded baseline at 6 months postoperatively, while step counts did not (all P < 0.05).

Conclusions: Continuous data from accelerometers allowed for identification of 3 distinct stages of postoperative recovery after lumbar laminectomy. PROMs remain necessary to capture subjective elements of recovery.