How many physical therapy sessions are required to reach a good outcome in symptomatic lumbar spondylolisthesis? A retrospective study.

Background: There is a lack of conclusive information about the optimal dosage of physical therapy treatments in Spondylolisthesis (SPL) patients.

Purpose: The present study attempted to evaluate the comparative effectiveness of two different doses in reaching similar clinical outcomes.

Methods: A retrospective cohort study of 64 consecutive patients admitted for physical therapy with symptomatic lumbar grade I SPL (42 ± 15years, 57% female) was conducted. At the end of the treatment, all participants were retrospectively assigned to one of two groups, receiving either 5-8 or 9-12 sessions (experimental or control group, respectively) of physical therapy treatments. The Prone Bridge Test (PBT) and the Supine Bridge Test (SBT) were used to measure muscular endurance.

Results: The area under the ROC curve for the PBT was 0.64 (95% CI 0.45-0.83) and for the SBT was 0.57 (95% CI 0.33-0.80). The optimal cutoff points were 25.5s for the PBT and 55.0s for the SBT. Logistic regression revealed that PBT (OR = 1.062) was associated with SPL. The final regression model explained 77.4% (R = 0.341; p = 0.024) of the variability.

Conclusions: In this sample, the number of sessions required to achieve satisfactory outcomes ranged from 5 to 12. The clinical results of the subjects in the 5-8 sessions group were similar to the 9-12 sessions group. Individual's coping mechanisms could be considered in future studies to understand which patients will require more therapeutic sessions.