Objectives: To evaluate whether protein supplementation improves mobility recovery, nutritional markers, mortality rates, and postoperative complications in elderly patients after proximal femoral fractures.

Design: Prospective, randomized, double-blind, placebo-controlled clinical trial.

Setting: Tertiary academic orthopaedic centers.

Patient selection criteria: Adults 60 years and older with radiographically confirmed proximal femoral fractures (OTA/AO 31-A1, 31-A2, 31-A3,31-B1, 31-B2, and 31-B3) requiring surgery were eligible. Exclusion criteria included prior supplement use, periprosthetic fractures, renal impairment, severe systemic disease, or contraindications to supplementation. Participants were randomized to receive either a creatine- and HMB-enriched protein supplement or an isocaloric maltodextrin placebo, administered once daily for 1 month.

Outcome measures and comparisons: The primary outcome was mobility recovery measured using the Parker Mobility Score (PMS), compared between groups at 1 and 6 months. Secondary outcomes included serum albumin, hemoglobin, lymphocyte count, total protein, mortality, and postoperative complications. Planned comparisons evaluated biochemical changes from baseline to 1 month, mortality across 6 months, and complications within 1 month.

Results: The intervention group (N = 40) had a mean age of 72.3 ± 8.7 years (range: 60-88), with 52.5% men, while the control group (N = 40) had a mean age of 73.2 ± 8.9 years (range: 60-90), with 42.5% men. Baseline demographic characteristics were comparable between the 2 groups. At 1 month, the intervention group showed higher PMS (4.83 ± 0.85 vs. 2.65 ± 0.63; P < 0.001), with no difference at 6 months (6.33 ± 2.4 vs. 6.19 ± 2.9; P = 0.859).At 1 month, albumin normalization was observed in all patients in the intervention group compared with 85% of patients in the control group; however, this difference did not remain statistically significant after Bonferroni adjustment (adjusted P = 0.219). Other nutritional markers showed no significant intergroup differences (all adjusted P > 0.05). Supplementation was associated with a lower 6-month mortality rate (HR 4.5; 95% CI, 1.12-18.26; P = 0.034). Complication rates within 1 month were similar between groups (N = 4 vs. N = 8; P = 0.20).

Conclusions: In elderly patients with hip fracture, creatine- and HMB-enriched protein supplement improved early mobility, accelerated albumin normalization, and was associated with lower 6-month mortality, without affecting complication rates.