39. Preliminary assessment of lumbar discectomy patient balance recovery: Is a force plate necessary or will a yard stick suffice?

Abstract

<h3>BACKGROUND CONTEXT</h3> Lumbar disc herniations (LDH) cause significant deficits in health-related quality of life and can greatly impact physical activity level. Considering that balance ability has been shown to be negatively impacted by LDH, balance testing provides meaningful assessment of preoperative functional deficits and postoperative recovery. Objective assessment of balance can be done using both simple clinical tests or sophisticated equipment like force plates. Guidance is needed on whether force plate analysis is necessary to adequately assess LDH patient balance before and after treatment or if simpler tests suffice. <h3>PURPOSE</h3> Determine if the Y-Balance test (YBT) provides comparable assessment of LDH patient balance recovery to force plate analysis following lumbar discectomy. <h3>STUDY DESIGN/SETTING</h3> Preliminary analysis of a prospective, concurrent-cohort study at a single institution. <h3>PATIENT SAMPLE</h3> LDH patients undergoing lumbar discectomy and healthy (H) controls. <h3>OUTCOME MEASURES</h3> PROMs: VAS pain, ODI; Force plate center of pressure (COP) measures: sagittal (s) and coronal (c) range of sway (ROS) normalized to base of support, 95% sway ellipse area (SE), average sway velocity (AV); YBT reach distances. <h3>METHODS</h3> LDH patients were evaluated 4 times: before (P0), 2 weeks after (P2w), 6 weeks after (P6w) and 3 months after (P3m) surgery. Subjects completed patient-reported outcome measures (PROMs), a 60s standing balance test, and YBT. Standing balance measures included force plate COP measures. YBT measures forward (F), back-lateral (BL), and back-medial (BM) leg reach distances of the dominant leg normalized by leg length. <h3>RESULTS</h3> A total of 51 LDH (12F/39M, 45±12yr, 95±22kg, 1.8±0.1m, 30±7kg/m2) and 10 H (8F/2M, 34±18yr, 70±10kg, 1.7±0.1m, 25±3kg/m2) subjects were included. PROMs showed significant improvements (all p 0.05). LDH AVc (5.6±5.7m/s, p=0.998) and AVs (8.7±4.0m/s, p=0.612) were not significantly different than H (AVc=5.6±2.6m/s; AVs=8.0±3.6m/s) at P0 and remained so across all follow-ups (all p >0.05). All P0 LDH YBT distances (F=56.1±10.3%; BL=76.0±12.5%; BM=55.4±14.9%, all p <0.001) were shorter than H (F=71.5±11.2%; BL=95.1±9.6%; BM=87.0±7.7%). After surgery, all LDH YBT reach distances showed significant improvements at P2w (F=61.4±8.9%, p=0.027; BL=83.3±11.2%, p=0.013; BM=64.1±14.5%, p=0.015) and P6w (F=65.1±8.8%, p=0.001; BL=83.4±12.3%, p=0.032; BM=64.9±18.4%, p=0.032) relative to P0. All directions remained significantly shorter than H (all p <0.05) at all follow-ups, except F at P6w which normalized (p=0.069). <h3>CONCLUSIONS</h3> COP and YBT both found immediate improvements in balance following LDH surgery. YBT provides a comparable assessment of LDH patient balance recovery to force plate analysis and should be considered a viable alternative. Objective functional measures for LDH surgery provide important indicators of postoperative recovery and treatment outcome. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.