Mechanical Diagnosis and Treatment and/or Steroid Injections for Lumbar Radiculopathy

Study Purpose and Specific Objectives: This pilot study aims to determine the feasibility of conducting a definitive clinical trial of MDT +/- TESI in patients awaiting physiatry consult for lumbar radiculopathy secondary to lumbar disc herniation compared to usual care.

Research Design and Methodology:

Design and participants: Randomised clinical trial pilot study. Eligible candidates will be identified by Physiatrists at a Physiatry clinic in Calgary. The investigators will recruit 30 patients (15 per group). Fifteen - twenty subjects per group provide reasonable bias-corrected estimates for medium effects. Inclusion criteria: Leg dominant pain secondary to lumbar disc protrusion confirmed on MRI with duration > 3 months, at least one neurological sign and able to speak English and provide written informed consent. Exclusion criteria: pregnancy and specific causes of low back pain (LBP) not directly related to herniated discs, progressive neurological signs and/or cauda equine syndrome, or contraindication for the use of corticosteroids or fluoroscopy. Consecutive patients will randomised into either the intervention described below to enable an estimation of the magnitude of the treatment effect or the usual care will be followed to estimate the magnitude of effect for the control group.

Interventions: Group 1- Control group: Outcome assessments will be conducted on patients on the wait list for physiatry consultation at baseline, 6 weeks, and 3 months. Group 2 - Intervention group (MDT group): Consistent with the MDT approach, patients will be initially assessed for centralisation over 2 visits by a Credentialed MDT therapist and further classified into centraliser (group 2a) and non-centralising pain responses (group 2b). A centralising pain response is defined as those whose most distal pain is reduced and retreats toward mid-line (e.g., pain now above knee) in response to certain postures and repeated end-range movement testing. Group 2a, Centralisers: Patients with a centralising pain response will continue with treatment based on MDT principles and will complete an exercise diary to indicate the frequency in which the exercises were performed daily. Group 2b, Non-centralisers: Patients with a non-centralising pain response will be offered TESIs followed by MDT. TESIs of 20mg dexamethasone and 0.5cc lidocaine 2%, under fluoroscopic guidance with contrast medium (Omni Pac 240) as described by the Spine Intervention Society (SIS) guidelines will be provided. Segment level will be determined based on MRI findings in combination with the clinical examination findings.

Two weeks after completion of the MDT or TESI intervention, patients will be reassessed and treated in a manner consistent with their presenting pain response classification: 1) resolved: advice on remaining active; 2) centralising: treated according to MDT principles with direction specific exercises and postural advise; 3) non-centralising but significant less pain: advice to remain active, with respect for worsening leg pain; and 4) persisting high levels of pain and/or disability: advise to remain active as tolerated and consult family physicians. Those who continue to perform MDT exercises will complete an exercise diary to indicate the frequency in which the exercises were performed daily

Outcome assessments: Assessing and treating therapists are credentialed in MDT and will be blinded to outcomes. The following outcomes will be assessed in all groups at baseline, 6 weeks, and 3 months. The primary outcome measures will be the Roland-Morris Disability Questionnaire (RMDQ) adapted and validated for sciatica, leg pain intensity, and global perceived effect (GPE). Average leg pain intensity will be measured using a numeric rating scale ranging from 0 (no pain) to 10 (worst imaginable pain) over the past 24 hours. GPE will be measured using a 7 point Likert scale, with lower scores suggesting recovery and higher scores suggesting worsening. Secondary outcome measures will include fear avoidance (FABQ), general health (SF-12), and medication use. Demographics will also be collected. In addition, participants who are prescribed exercises will complete a diary indicating the frequency at which the exercises were performed.

Data analysis: Leg pain intensity at 3 months, measured using a 10 point numeric rating scale (NRS) will be the primary outcome for which the larger more definitive study will be planned. An independent t-test will be used to estimate the effect sizes of the intervention group compared to the control group. Independent t-tests will also be applied to the other outcome measures for exploratory purposes. Statistical significance will be set at α=0.05. Descriptive statistics will be calculated.