Introduction: Lumbar decompression for radiculopathy secondary to nerve root compression is a common procedure, leading to improvement in function in the appropriately selected patient.1 Continuous, remote objective measurement of patients’ function offers a novel approach for characterizing disability and surgical outcomes.2-5 We describe and validate a spine-specific wearable system to capture trunk kinematics, spatiotemporal parameters, and type of activity in the post-operative patient.2 Therefore, the purpose of this study was to assess the effect of lumbar decompression and fusion on patient’s disability utilizing spine specific wearables.
Methods: Patients underwent lumbar spine decompression with fusion. A week before (Pre) and 3 month following surgery (Post3), spine specific wearables were attached to patient’s base of neck and passively recorded disability and functional outcomes for 3 days. At the end of each day, ODI and PROMIS were answered by patients. Repeated-measurements ANOVA was used to compare outcomes before and after surgery using SPSS (IBM 2023).
Results: Disability and function were improved following lumbar decompression and fusion as cited by spine-specific wearables and PROMIS. The volume of activities was significantly increased following surgery (% of the day; walking Pre: 16.0±9.1 vs Post3: 24±8.7, p<0.05;). Moreover, trunk RoM was increased (Sagittal: Pre: 30.4±11.3 vs Post3: 45.2±15.6⸰, p<0.05, Coronal: Pre: 30.0±12.9 vs Post3: 45.4±12.9⸰, p<0.05). Furthermore, PROMIS and ODI scores were significantly improved (PROMIS Physical Function: Pre: 71.1±9.7 vs Post3: 58.5±12.4, p<0.05; PROMIS Pain Interference: Pre: 69.4±11.4 vs Post3: 56.7±10.1, p<0.05; PROMIS Mood: Pre: 65.9±4.0 vs Post3: 60.1±7.7, p<0.05; ODI: Pre: 45.9±12.7 vs Post3: 32.3±11.7, p<0.05;). Although, DFOMs were improved in LD patients, they were still significantly different from an age and gender matched controls (p>0.05). LD patients presented with lower free-living physical function along with reduced trunk kinematics (walking: 4.7±2.1%, standing: 11.6±3.6%, sitting: 25.3±12.8%, and laying down: 41.7±12.2% of the day, trunk flexion: 15.8±6.7°) at their home-based environment in comparison to controls (walking: 8.9±2.1%, standing: 19.1±4.9%, sitting: 17.1±9.7%, and laying down: 36.2±11.0% of the day, trunk flexion: 10.3±4.7°; p<0.05). Moreover, LD patients demonstrated reduced balance and gait with increased sway (balance effort: 25.6±11.7°, walking: 0.8±0.3 m/s, sway: sagittal: 7.9±2.8°, coronal: 7.2±3.0°) compared to controls (balance effort: 14.6±5.7°, walking: 1.0±4.4 m/s, sway: sagittal: 5.8±2.5°, coronal: 3.2±1.3°; Figure 2). Strong correlations were found between wearable DFOMs to the PROMIS scores (r2 >0.55, p<0.05).
Discussion: Lumbar decompression and fusion have been demonstrated to decrease disability and improve function in patients with radicular pain caused by nerve root compression. A novel spine-specific wearable system was able to quantify the patient’s disability and functional level, with a good correlation to improvements reported in PROMs. A combination of disability and function outcome measurements (DFOMs) to supplement PROMs and radiographic measurements provides a more comprehensive evaluation of a spine patient’s health and assists physician planning treatment. It may also be possible for healthcare providers to view their patients' DFOMs in real-time, allowing them to monitor their progress and refine their patient care accordingly.