Feasibility of Prehab for Lumbar Spinal Stenosis

Background:

Lumbar spinal stenosis (LSS) is the most common degenerative condition among older adults, and the leading reason older adults aged 65 and older undergo surgery. LSS is characterized by degenerative changes that lead to loss of intervertebral disc spaces, joint thickening, and enfolding of the ligaments surrounding the spine. These degenerative changes may cause compression of lumbosacral nerve roots resulting in the narrowing of central and vertebral canals known as neurogenic claudication (NC). The symptoms of NC include cramping, numbness or tingling, and muscle weakness in the lower back, buttocks, or one or both legs, with symptoms often intensifying with standing and walking.

The majority of individuals undergoing surgery for LSS are post-retirement age, have chronic low back pain, without access to private rehabilitation. This population is often severely deconditioned prior to surgery with weakness and atrophy of the muscles in the back, core, and lower limb. These preoperative factors have been shown to be predictors for postoperative LSS outcomes. Studies have shown evidence of the effectiveness of prehabilitation programs on post-operative recovery for other musculoskeletal conditions such as total knee arthroplasty. However, there appears to be a lack of high-quality evidence for the effect of prehabilitation interventions in improving outcomes for LSS surgery.

Research Aims:

The purpose of this study is to determine the feasibility of the program of care on a group of patients with LSS undergoing surgery, and determine the feasibility of the protocol for a randomized controlled trial.

Methods:

This mixed methods study will include a two-armed, pilot RCT evaluating an 8-week virtual prehabilitation program for participants undergoing LSS surgery, with a longitudinal qualitative study conducted parallel to the pilot RCT. The two groups in the RCT study will be: 1) prehabilitation, and 2) usual care.

Recruitment:

There will be 60 participants recruited from participating spine surgeons in 3 Canadian cities - Hamilton, Edmonton, and Calgary. Participants will be included if 1) they are a minimum 20 weeks prior to their date of surgery, 2) older than 55 years of age, 3) are scheduled for first spine surgery , and 4) are English-speaking. Participants will be excluded if 1) they have a known or suspected pathology (e.g., cancer, cauda equina syndrome), 2) are unable to engage in exercise due to other comorbidities or cognitive issues, and 3) if they do not have access to the Internet.

Interventions:

The 8-week prehabilitation program will be delivered online using synchronous and asynchronous sessions delivered by either a physiotherapist, chiropractor or kinesiologist, with a booster session at 6-weeks post-op. There will be 4 individual exercises sessions (week 1, 2, 4 and 8) delivered synchronously using Zoom or Physitrack in which motivational interviewing and graded activity exercises will be conducted. Participants will also be asked to exercise at least 3 times a week using the asynchronous exercise videos. Participants will receive short online educational videos (3-5 minutes). Educational sessions will include information regarding the importance of exercise, pain education, self-management, exercising despite pain, post-operative expectations, and information regarding their upcoming surgery. The educational sessions will also include two online peer-support groups when they can interact with a patient with a history of LSS surgery.

Participants in the control group will receive usual care for LSS surgery, which will consist of one session with an anesthesiologist, a nurse and access to our online educational videos.

Outcomes:

Outcomes will be evaluated at: baseline (~20 weeks before LSS surgery), immediately after the intervention (8-weeks), 3 and 12 months post-operatively. Feasibility outcomes are: 1) recruitment rate; 2) patient adherence to the program and attrition rates; 3) acceptability of program content; and 4); acceptability of study procedures and completion of study questionnaires. Patient reported outcomes will be used to inform feasibility, study burden and sample size calculations. These outcomes include: pain and disability, health-related quality of life, psychological measures, and monitoring variables. Ecological Momentary Assessments using activity monitors will be used to evaluate walking ability and daily pain.

Qualitative Methods A longitudinal qualitative study will be conducted parallel to the pilot RCT. We will use purposive sampling to conduct in-depth semi structured interviews at baseline (~20 weeks before LSS surgery), 8-weeks after the intervention, 3 months, and 12 months post-operatively. For the qualitative study, we will aim to recruit 12-15 participants or until saturation is met. The longitudinal qualitative study will assess the barriers and facilitators that influence engagement in prehabilitation, as well as the changes in pain and health that occur over time and how these are related to the program, personal (e.g., sex and gender, age, comorbid health, pain profile) or contextual factors (psychosocial, environmental, health systems).

Analysis:

All analyses will be conducted using STATA 15. Descriptive statistics will be used to report feasibility outcomes, as well as to identify trends in patient-reported outcomes. Qualitative interviews will be analyzed using interpretive phenomenological analysis (IPA) informed by the Consolidated Criteria for Reporting Qualitative Studies. Inductive thematic analysis will be used to analyze the data and report the study findings.