Time Courses of Adaptation in Lumbar Extensor Performance of Patients With a Single-Level Microdiscectomy During a Physical Therapy Exercise Program

Abstract

l umbar spine surgery can expedite improvements in pain and dysfunction associated with a herniated lumbar disc. 19 Consequently, over 250 000 surgeries are performed each year in the United States alone.1 A commonly used surgery is the single-level microdiscectomy ( S L M ) , in which a damaged portion of the intervertebral disc is removed. While the standard of care for therapy following a t sTuDY Design: Longitudinal single-cohort study. t MeTHoDs: Patients (n = 48) with a single-level microdiscectomy participated in a 12-week (36 sessions) comprehensive strength and endurance exercise program starting 4 to 6 weeks postsurgery. Lumbar extensor strength was quantified as the degree from horizontal on a modified Sorensen test procedure. Patients unable to assume the horizontal position were assumed to have strength deficits. Lumbar muscular endurance performance was quantified by the amount of time patients could hold the Sorensen test position at the horizontal. The time rate of lumbar muscular endurance adaptations were analyzed using longitudinal growth curve modeling.t resulTs: The adherence rate of this program was low (67%). Twenty percent of the patients were identified as having strength deficits. These deficits were corrected in all patients within 3 to 9 weeks. Linear mixed-model results suggest an improvement of 5.6 seconds in hold time per week of exercise. Both the initial level of endurance and the rates of improvements were highly individualized.t ConClusion: The time course of musculoskeletal performance adaptations in persons with a history of lumbar surgery is highly individualized. When compared to normative endurance times, the results of this study indicate that the number of sessions and duration of therapy needed to generate meaningful adaptations of the paraspinal musculature is longer than what is typically provided in the clinic postsurgery. t leVel oF eViDenCe: Therapy, level 4.

Early multimodal rehabilitation following lumbar disc surgery: a randomised clinical trial comparing the effects of two exercise programmes on clinical outcome and lumbar multifidus muscle function

“…While most trials until now have assumed this patient population to be homogeneous in nature, we do not know this to be the case. Preliminary evidence supporting the hypothesis of patient heterogeneity was reported by Flanagan et al 46 who implemented a 12-week strength and endurance exercise programme after lumbar microdiscectomy. The authors reported that adaptations in lumbar extensor muscle performance were highly individualised.…”