Prevalence of Sarcopenia in Patients with Hip Osteoarthritis Undergoing Total Hip Arthroplasty: A Cross-Sectional Study Based on EWGSOP2 Criteria

(1) Background/Objectives: Sarcopenia is common in older surgical candidates and may affect perioperative risk and recovery after total hip arthroplasty (THA). Quantifying its burden and severity gradient in THA pathways can inform surgeon-led optimization. (2) Methods: A cross-sectional analysis of baseline preoperative data at a tertiary center (December 2019 to December 2022) was conducted. Consecutive adults with hip osteoarthritis undergoing primary THA were screened. Sarcopenia was staged per EWGSOP2: probable (low handgrip), confirmed (probable and low skeletal muscle index by whole-body DXA), and severe (confirmed and low gait speed). (3) Results: Of 312 screened patients, 203 completed baseline assessment (95 men, 108 women). According to the EWGSOP2 algorithm, 57 patients (28.1%; 95% CI 22.3–34.6%) had low handgrip strength, 30 (14.8%; 95% CI 10.6–20.3%) fulfilled criteria for confirmed sarcopenia, and 21 (10.3%; 95% CI 6.9–15.3%) had severe sarcopenia. No significant association was observed for sex. Sarcopenia diagnosis was associated with older age, lower body mass index (BMI), higher comorbidity burden, lower functional independence, greater cognitive impairment, poorer mental health, and worse hip-related function (all p < 0.05). In multivariable analysis, older age (OR 1.51 per 5-year increase; 95% CI 1.11–2.12), lower BMI (OR 0.88 per kg/m2; 95% CI 0.79–0.98), and lower functional independence (Barthel Index: OR 2.02 per 10-point decrease; 95% CI 1.20–3.60) were independently associated with confirmed sarcopenia. Across EWGSOP2 categories, differences in age, BMI, pain, comorbidity, functional independence, cognition, mental health and hip function showed significant differences (all p < 0.05), with ordered trends in most domains but no uniform monotonic pattern. (4) Conclusions: In THA candidates, sarcopenia is prevalent and is related to older age, lower BMI and lower functional independence. Integrating sarcopenia screening by EWGSOP2 may help to identify THA candidates with greater clinical vulnerability who may warrant further preoperative assessment and targeted optimization strategies.