Introduction. The prevalence of sarcopenia is higher in lumbar canal stenosis patients than the general population. However there are few studies regarding the relationship between sarcopenia and spine surgery. It remains unclear how sarcopenia affect the clinical outcome of lumbar decompression surgery. The aim of this study is to investigate the influence of sarcopenia on the clinical outcome in lumbar decompression surgery.
Methods. Seventy patients who underwent lumber decompression surgery from 2020 to 2022 were reviewed retrospectively. Patients under 60 years old were excluded. Patients were divided into three groups: normal group, sarcopenia group and severe sarcopenia group based on the AWGS 2019 criteria. We compared age, gender, body mass index (BMI), the number of decompression spinal segment among three groups. Clinical outcomes were assessed using measures including Visual analog scale (VAS) of lumbar pain, leg pain VAS, leg numbness VAS, Oswestry Disability Index (ODI), Roland-Morris Disability Questionnaire (RDQ), and satisfaction rate. The clinical outcomes were compared between preoperative and one-year postoperative period.
Results. There were 42 men and 28 women with an average age of 73.8 years old (61-89). The mean BMI was 25.5 kg/m2 (19.7-33.8), the mean number of decompression spinal segment was 2 segments (1-4). Regarding classification of sarcopenia, 52 patients were classified as normal group, 12 patients as sarcopenia group, 6 patients as severe sarcopenia group. Prevalence of sarcopenia was 25.7%. Although there was no significant difference in age, gender, and the number of decompression segments, BMI was significantly higher in normal group than sarcopenia group (normal vs sarcopenia vs severe sarcopenia: 26.3 vs 22.7 vs 24, p<0.01). Preoperative VAS of lumbar pain, ODI, RDQ were significantly higher in sarcopenia and severe sarcopenia group (44.9 vs 74.3 vs 60, p=0.02 / 45 vs 57.3 vs 71.8, p<0.01 / 11.8 vs 16 vs 18.5, p<0.01). In one-year postoperative periods, all groups showed significant improvement in symptoms. However, VAS of leg pain, ODI, RDQ were significantly higher in sarcopenia and severe sarcopenia group compared to normal group (7.9 vs 27.6 vs 13.5, p=0.02 / 13.5 vs 21.6 vs 33.7, p<0.01 / 2.2 vs 6.5 vs 5.2, p=0.02).
Conclusion. The prevalence of sarcopenia was 25.7% in lumbar canal stenosis patients. Although all groups showed significant improvement in symptoms, the postoperative clinical outcomes were worse in sarcopenia and severe sarcopenia group compared to normal group. This result suggests that sarcopenia might affect the clinical outcomes in lumbar decompression surgery.