Study design: A retrospective cohort study.
Objective: To compare the cost of maximum nonoperative therapy (MNT) in patients diagnosed with a herniated lumbar disk undergoing primary (1-3 mo) versus prolonged (4-6 mo) conservative management before microdiscectomy.
Summary of background data: Patients diagnosed with a herniated lumbar disk often attempt a 3-month trial of conservative management before microdiscectomy. A paucity of data exists characterizing the cost of a subsequent round of nonoperative therapies in patients who fail their initial trial, rather than undergo surgery.
Methods: Clinical records from patients diagnosed with a herniated lumbar disk undergoing index microdiscectomy surgery from 2007 to 2017 were gathered from a large insurance database. Records were searchable by International Classification of Diseases diagnosis/procedure codes, Current Procedural Terminology codes, and generic drug codes. Two cohorts were established: patients undergoing primary (1-3 mo) versus prolonged (4-6 mo) courses of conservative management. Nonoperative therapy utilization was documented from initial herniation diagnosis to microdiscectomy surgery. "Utilization" encompassed cost billed to patients, prescriptions written, and quantity of units dispensed.
Results: The 3-month MNT cohort included 4587 patients and the 6-month MNT cohort contained 1506 patients. A greater percentage of 6-month cohort patients utilized opioids (P=0.0052), muscle relaxants (P=0.0061), and lumbar steroid injections (P<0.0001). When considering the average amount spent on conservative management, 6-month patients ($1824/patient) spent 1.55 times more than 3-month patients ($1178/patient). The 6-month:3-month average spending ratio was <2.0 for all of the nonoperative therapies except nonsteroidal anti-inflammatory drugs (2.66) and epidural steroid injections (2.25). When normalized by the number of opioid users, the number of opioid medications dispensed was proportionally less in 3-month patients compared with 6-month patients, with a 6-month:3-month ratio of 1.52.
Conclusions: The costs associated with a subsequent course of nonoperative therapies for symptomatic lumbar disk herniation seem to be slightly less than that of the primary trial. Assuming a minimal clinical benefit after the initial trial of nonsurgical therapies, the incremental cost-effectiveness ratio of a subsequent trial versus surgery may be unfavorable. Future studies identifying patients likely to benefit from surgery earlier in the treatment course is required.
Level of evidence: Level III.