Assessment of health-related quality of life after surgical treatment of focal symptomatic spinal stenosis compared with osteoarthritis of the hip or knee.

BACKGROUND CONTEXT

In the last decade, the number of patients undergoing surgical treatment for lumbar spinal stenosis (LSS), particularly instrumented fusions, has significantly increased. The surgical procedures for LSS represent a significant cost to the health-care system and are a priority focus for most governments, insurers, hospital administrators, and spine care physicians.

PURPOSE

The purpose of this study was to directly compare the relative improvement in self-reported quality of life after surgical intervention for matched groups of patients with primary hip or knee osteoarthritis (H-OA/K-OA) and focal lumbar spinal stenosis (FLSS).

STUDY DESIGN/SETTING: Observational cohort study of prospectively collected outcomes.

PATIENT SAMPLE

Patients, following elective primary one- to two-level spinal decompression (n=90) with (n=28/90) or without fusion for FLSS, were compared with a matched (age, sex, and time of surgery) cohort of patients who had undergone elective total hip (n=90) or total knee (n=90) arthroplasty (total joint arthroplasty [TJA]) for primary osteoarthritis.

OUTCOME MEASURES

Medical Outcomes Study Short Form-36 (SF-36).

METHODS

Patents were obtained for prospective outcomes databases (TJA and spine). Inclusion and exclusion criteria were independently applied, and matching was performed in a blinded fashion. The primary outcome measure was the relative change between preoperative and 2-year postoperative SF-36 questionnaires. Data were analyzed with the t test and repeated measures analysis of variance (ANOVA).

RESULTS

The three groups (FLSS/H-OA/K-OA) were equally matched with respect to mean age (64/63/65 years), sex (female/male, 51/39 for all groups), body mass index (BMI) (27/24/27), and American Society of Anesthesiologists (ASA) physical status (2/2/2). Comparison of preoperative SF-36 physical component summary (PCS) scores and mental component summary (MCS) scores between groups showed no statistical difference (PCS: FLSS=32.0, H-OA=30.2, K-OA=31.3 [p=.32, ANOVA]/MCS: FLSS=43.5, H-OA=45.0, K-OA=46.2 [p=.25, ANOVA]). Postoperatively, PCS improved significantly for all groups (1 year-PCS: FLSS=39.6, H-OA=44.5, K-OA=38.5 [p<.0001 for all groups]; 2 years-PCS: FLSS=38.6, H-OA=43.2, K-OA=37.1 [p<.0001 for all groups]). At both 1- and 2-year follow-ups, the PCS improvement between groups was greater for the H-OA group compared with the FLSS (p=.0037, p=.0073) and K-OA (p=.00016, p=.00053) groups. At the 1-year follow-up, MCS did not significantly increase for any group; however, 2 years postoperatively, MCS improved significantly for the FLSS and H-OA groups (2 years-MCS: FLSS=50.3, H-OA=50.9, K-OA=44.8 [p=.00021, p=.00079, p=.35]). At the 1-year follow-up, there was no statistical difference in MCS improvement between groups (p=.45, ANOVA). Two years postoperatively, the MCS for both the FLSS and H-OA groups was significantly greater than that for the K-OA group (p=.0014, p=.00055).

CONCLUSIONS

The results of this study show that surgical intervention for FLSS can obtain and maintain improvement in self-reported quality of life comparable to that of total hip and knee arthroplasty. This study provides data to support the need for prospective cost-effectiveness studies for the surgical management of appropriately selected patients suffering from FLSS.