Effects of Sarcopenia on Surgical Outcomes After Biportal Endoscopic Lumbar Decompression and Fusion: A Retrospective Observational Study.

STUDY DESIGN: Retrospective, single-center study. OBJECTIVE: To evaluate the effects of sarcopenia on perioperative parameters and postoperative outcomes in patients undergoing biportal endoscopic lumbar surgery. SUMMARY OF BACKGROUND DATA: Sarcopenia is associated with adverse surgical outcomes. However, its impact on minimally invasive procedures, particularly biportal endoscopic lumbar surgery, remains unclear. METHODS: We retrospectively analyzed data from 153 patients who underwent biportal endoscopic lumbar surgery (decompression, n=101; fusion, n=52) between October 2021 and November 2023. Patients were classified into sarcopenia and non-sarcopenia groups based on appendicular skeletal muscle mass (ASM), handgrip strength, and 6-m gait speed. Demographic characteristics, perioperative parameters, clinical outcomes, and complication rates were compared between the groups. Outcomes were assessed from the preoperative period to 12 months postoperatively. RESULTS: ASM and 6-m gait speed were significantly lower in patients with sarcopenia, within both decompression and fusion cohorts (P<0.001). The Oswestry Disability Index and EuroQol-5D index improved in all groups, without significant between-group differences at 12 months postoperatively. In the fusion group, patients with sarcopenia had a significantly longer hospital stay (15.0 vs. 11.9 d, P=0.003), despite similar operative time and estimated blood loss. Postoperative C-reactive protein and creatine phosphokinase levels were higher in patients with sarcopenia undergoing fusion, without reaching significance. Complication rates were equivalent in all groups. CONCLUSIONS: Sarcopenia was not associated with inferior clinical outcomes or higher complication rates following biportal endoscopic lumbar surgery. However, patients with sarcopenia undergoing fusion surgery experienced a longer hospital stay, suggesting delayed early postoperative recovery. Overall, biportal endoscopic lumbar surgery may be an acceptable surgical option for patients with sarcopenia.