comparison of functional recovery after total knee arthroplasty between low phase angle and high phase angle group

Conditions: Knee Osteoarthritis

Summary: the goal of this observational study is to compare the functional outcome of patients with end-stage knee osteoarthritis (oa) before and after total knee arthroplasty based on the phase angle level. the main questions it aims to answer are: * do patients with low phase angle show worse functional recovery after total knee arthroplasty compared to those with high phase angle? * is postoperative physical function associated with preoperative phase angle level? researchers will compare postoperative physical function and muscle strength between the low and high phase angle groups to determine whether a low phase angle is associated with poorer functional recovery. participants will: perform physical function tests, isokinetic strength assessments, and bioelectrical impedance analysis before and three months after surgery.

after obtaining informed consent, a pre-surgical screening is conducted. participants complete a history survey, a sarcopenia questionnaire, and the international physical activity questionnaire (ipaq). the screening includes a comprehensive evaluation of baseline symptoms, followed by functional assessments that incorporate bioelectrical impedance analysis, muscle strength testing, and performance-based tests: * a modified charlson comorbidity index (cci) is used to assess comorbidity burden, and a numeric pain rating scale (nprs) records participants' initial pain levels. * radiographic assessments are performed to evaluate the frontal alignment of the lower extremities and the radiographic severity of knee osteoarthritis (oa) using the kellgren-lawrence (k-l) grading system. * multifrequency bioelectrical impedance analysis (bia) is used to measure phase angle and body composition. * handgrip strength is measured through three trials on each side, with the average recorded. * knee strength is measured using an isokinetic dynamometer. * performance-based tests include the 10-meter walk test, the timed up and go (tug) test, and the berg balance scale (bbs). follow-up assessments are conducted three months after total knee arthroplasty, with participants undergoing the same protocol for performance-based tests, isokinetic knee strength evaluation, and bioelectrical impedance analysis.

Eligibility criteria:
inclusion criteria: * individuals aged 55 and over (based on the age on their national id at the time of consent) * individuals diagnosed with knee oa based on medical history, physical examination, and radiographic assessments. * individuals who plan to perform total knee arthroplasty exclusion criteria: * individuals with gait disturbance due to neurologic disorders such as parkinson disease, stroke and dementia * individuals with severe cardiac, pulmonary, or musculoskeletal disorders that limited quadriceps strength and physical function * individuals with knee osteoarthritis due to secondary causes such as rheumatic or traumatic arthritis * individuals with a history of any knee surgery within one year. * individuals considered clinically unsuitable for the study by the researchers or person in charge based on significant medical findings.

Keywords: total knee arthroplasty phase angle sarcopenia bioelectrical impedance