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

Abstract

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.

Introduction

The aging population is resulting in an increasing burden of degenerative illness that will only continue to have a progressive impact on both human and financial health-care resources [1], [2], [3], [4], [5], [6], [7]. For musculoskeletal disorders this is already evident in the increasing rates of patients undergoing surgery for degenerative conditions such as hip or knee osteoarthritis (H-OA/K-OA) and lumbar spinal stenosis (LSS) [2], [3], [4], [5]. The surgical management of symptomatic hip and knee arthritis typically involves the use of joint replacement implants (total joint arthroplasty [TJA]), whereas the current management for symptomatic LSS involves decompression alone or decompression and fusion. In particular, procedures requiring implants potentially represent a significant cost to any health-care system and are under significant scrutiny [2]. As the demand for such procedures is on a predictable increase, issues such as utilization, cost-effectiveness, surgical waiting times, and the resultant effects on scarce health-care resources are an ongoing priority health policy focus [2], [3], [4], [5], [6], [7], [8], [9], [10], [11], [12], [13], [14], [15].

The general demographics and comorbidities of patients with symptomatic LSS and hip or knee arthritis are very similar. Numerous studies have demonstrated reliable and sustained improvements in overall patient satisfaction, quality of life, and function after primary TJA [16]. In addition, hip and knee arthroplasty have shown to be cost-effective compared with other nonmusculoskeletal surgical procedures [16], [17], [18], [19]. Consequently, lower extremity TJA has gained widespread acceptance from governmental on and nongovernmental funding agencies. This, however, has not been the case for LSS.

The population of LSS patients represents a growing public health challenge for spinal surgeons around the world. For neurogenic claudication, the literature has shown that good outcomes after elective surgical management of LSS and stable relief can be maintained for up to 10 years [20], [21], [22]. Although there are increasing levels of scientific evidence demonstrating improved outcomes with surgical management of LSS, the heterogeneity of the indication(s) for and the outcomes of surgery makes strong conclusions and recommendations regarding health care difficult [20], [23]. The impact of surgical treatment of LSS on patient self-reported quality of life has never been directly compared with the benchmark set by TJA. To date, no study has directly compared the relative improvement in quality of life after surgical intervention for matched groups of patients with primary H-OA/K-OA and LSS. Our hypothesis is that contemporary patient selection and surgical management of LSS achieves a positive impact on patient quality of life comparable to that resulting from hip and knee arthroplasty for osteoarthritis.