ABSTRACT
Osteoarthritis is amongst the top five most disabling conditions affecting Americans over 65 years of age and imposes an annual economic burden estimated at $ 89.1 billion. Nearly half of the cost of care of Osteoarthritis is attributable to hospitalizations for total knee arthroplasties (TKA) and total hip arthroplasties (THA). The current clinical practice relies predominantly on subjective assessment of physical function and pain via patient reported outcome measures (PROM) that have proven inadequate for providing a validated, reliable and responsive measure of TKA outcomes. Wearable activity monitors, which produce a trace of regularly monitored physical activity derived from accelerometer measurements, provide a novel opportunity to objectively assess physical functional status in Osteoarthritis patients. Using data from the Osteoarthritis Initiative (OAI), we demonstrate the feasibility of quantifying the relative change in physical activity patterns in Osteoarthritis subjects using accelerometer based measurements of daily physical activity.
ABSTRACT
BACKGROUND CONTEXT: Medial branch radiofrequency neurotomy (RFN) is a common treatment for zygapophyseal joint pain. The lumbar medial branch innervates these joints and adjacent structures. The impact of the intended neurotomy on these structures remains unclear. No studies have yet verified quantitatively the effect of medial branch RFN on intervertebral discs, facet joints, and multifidus cross-sectional area. PURPOSE: The aim of this study was to determine, using objective radiographic measures, whether there is a quantitative difference in the lumbar multifidus muscle cross-sectional area, facet joint degeneration, or intervertebral disc degeneration after segmental medial branch RFN. STUDY DESIGN/SETTING: This is a retrospective single-cohort study performed at a university spine center. PATIENT SAMPLE: The patient sample consisted of 27 patients treated with lumbar medial branch RFN, with pre- and posttreatment magnetic resonance images available for analysis. OUTCOME MEASURE: The primary study outcome measure was interval change in fat-subtracted multifidus cross-sectional area, and intervertebral disc and zygapophyseal joint degeneration grade. METHODS: In this retrospective study, segmental levels unaffected by RFN treatment were used as controls to compare against levels affected by treatment. RESULTS: Levels affected by RFN demonstrated a significantly greater amount of disc degeneration compared with unaffected levels (14.9% vs. 4.6%; p=.0489). There was no statistical difference in the multifidus cross-sectional area or rates of deterioration in the zygapophyseal joints observed. CONCLUSIONS: The full impact of RFN on multifidus function, morphology, and segmental anatomy is unknown. This retrospective study indicates that measurable changes in segmental morphology may occur after lumbar medial branch RFN. These findings require validation in a prospective, controlled study.
