INTRODUCTION: Supervised physical therapy for patients with lumbar spinal stenosis (LSS) has been reported to produce greater improvements in symptom severity and physical function than unsupervised exercise and be associated with lower likelihood of receiving surgery within 1 year.¹ However, it is unknown how effective supervised physical therapy is compared with decompression surgery with or without fusion for LSS. The purpose of this study was to compare the 1-year follow-up outcomes of LSS patients treated with supervised physical therapy or surgery using a propensity score-matched analysis.

METHODS: Patients treated with supervised physical therapy twice a week for 6 weeks in a randomized controlled trial (PT group) and patients who underwent decompression surgery with or without spinal fusion in same institute (Surgery group) were included. Loss to follow-up at 1 year, receiving surgery or additional surgery within 1-year follow-up, previous spine surgery, spondylolysis and foraminal stenosis were excluded. Clinical outcomes included: the Zurich Claudication Questionnaire (ZCQ), a numerical rating scale (NRS) of low back pain, leg pain, and leg numbness, and the Medical Outcomes Study 36-item Short-Form General Health Survey (SF-36) at 1 year. The Hospital Anxiety and Depression Scale (HADS), Pain Catastrophizing Scale (PCS), and Pain Anxiety Symptoms Scale were used to evaluate psychological status at baseline. Propensity score matching (PSM) was used, including age, sex, body mass index, duration of symptoms, number of stenosis, %slip, presence of slippage, ZCQ symptom severity and physical function, NRS of low back pain, leg pain, and leg numbness, and SF-36 physical functioning, bodily pain, and mental health. At before and after PSM, clinical outcomes at baseline and 1 year were compared between the groups.

RESULTS: Thirty-eight patients (PT group) and 186 (Surgery group) patients (95 patients received decompression with fusion) were included in this study. At baseline before PSM, the Surgery group had higher number of stenoses, and worse scores on ZCQ symptom severity and physical function, SF-36 physical functioning, bodily pain, mental health, role physical, role emotional, and social functioning, PCS, and HADS anxiety than the PT group. At 1year before PSM, the Surgery group showed significant improvements compared with the PT group for ZCQ symptom severity and physical function, NRS of low back pain, and SF-36 physical functioning, bodily pain, role emotional, and mental health. Thirty-three pairs were selected by PSM. Fifteen out of 33 patients in the Surgery group received decompression with fusion. After PSM, there were no significant differences in all clinical outcomes at 1 year, except for the percentage of responders achieving minimum clinically important difference in SF-36 role emotional (PT group; 19.4% vs. Surgery group; 44.8%, P < 0.05).

DISCUSSION: The patients who underwent lumbar surgery showed greater improvements in clinical outcomes, but had more severe LSS symptoms than the patients who received supervised physical therapy at baseline. When baseline characteristics were considered, supervised physical therapy yielded similar effects to lumbar surgery among patients with LSS. These results suggest that surgery for LSS should be considered after supervised exercise therapy, especially in mild cases of LSS.