Severe hip and knee osteoarthritis worsens patient-reported disability in adult spinal deformity patients

Abstract

BACKGROUND CONTEXT: The complex interplay between lower extremity osteoarthritis and sagittal alignment in adult spinal deformity patients is of growing clinical interest. PURPOSE: To quantify the sequential effects of lower extremity OA on PROMs in ASD patients. STUDY DESIGN/SETTING: Retrospective review of prospectively collected data. PATIENT SAMPLE: ASD patients with no prior history of thoracolumbar surgery, and available baseline PROMs and standing radiographs were included. OUTCOME MEASURES: Baseline demographics, spinopelvic alignment, and PROMs. METHODS: Included patients with PROMs, standing xrays, no prior thoracolumbar surgery, and bilateral Kellgren-Lawrence (KL) hip/knee grade at baseline. Patients grouped into Spine (KL <3 BL hips & knees), Spine-Hip (KL>3 BL hips, KL <3 BL knees), Spine-Knee (KL>3 BL knees, KL>3 BL hips), Spine-Hip-Knee (KL>3 BL hips & knees). Baseline demographics, spinopelvic alignment, and PROMs were compared. Multivariate regression with forward stepwise selection predicted PROMs with variables (demographic, radiographic, OA severity) with significant association identified on Pearson correlation RESULTS: Included 160 patients: 56 Spine, 32 Spine-Knee, 20 Spine-Hip, and 52 Spine-Hip-Knee. Spine-Hip-Knee patients were older (Spine=62.2, Spine-Knee=61.2, Spine-Hip=59.1, Spine-Hip-Knee=68.5; p<.001) but similar in sex, comorbidities, and frailty; p>.05. Spine-Hip-Knee patients had higher SVA (50.0,30.6,60.5,83.5), T1PA (25.2,20.4,20.3,27.8), GSA (3.7,2.3,4.3,7.5), and KA (0.0,2.1,2.9,10.5); p<.005. SRS total and VR12 PCS scores were similar but VR12-2b climbing stairs (1.73,1.91,1.55,1.40, p=.014) and SRS-8 back pain at rest (2.29,2.84,1.95,2.71, p=.012) were lower in Spine-Hip-Knee and Spine-Hip, respectively. ODI (42.75,35.88,50.30,44.59, p=.040) and ODI Pain (2.88,1.84,2.90,2.46, p=0.019) were higher in Spine-Hip patients; ODI lifting was higher in hip OA patients but not significant (2.95,2.69,3.45,3.35, p>.05). In multivariate analyses, KOA changed the prediction of ODI pain from R2 0.052 to 0.086 and SRS-8 from R2 0.077 to 0.147. HOA changed the prediction of VR12-2b from R2 0.113 to 0.140 and ODI Lifting from R2 0.175 to 0.202. Frailty impacted PROMs across all models (p<.001) and GSA changed ODI, ODI pain, and VR12-2b models (p<.05). CONCLUSIONS: Severe hip and knee OA worsen patient-reported disability and physical function in ASD patients. These results quantify the impact of lower limb arthritis on patient reported outcomes, and highlight the need for integrated assessment and management of both spinal alignment and joint health in patients. FDA Device/Drug Status: This abstract does not discuss or include any applicable devices or drugs.