A Study to Validate Diagnostic Strength of Modified Slump Test in Lumbar Radiculopathy

Introduction: Neural tissue provocation tests (NTPT) have been increasingly incorporated into clinical practice. Unfortunately, the early terminology used in describing these tests-'neural tension test' and 'adverse mechanical tension'- did little to further the acceptance, understanding or credibility of the physical treatment of neurogenic pain. A more appropriate term is 'neural tissue provocation tests' as they are passive test applied in a manner to selectively stress different neural tissues in order to assess their sensitivity to mechanical provocation. Many experts in the field of neurodynamics have clearly stated the importance of the reproduction of a patient's symptoms, which implies the presence of pathology. The other feature which is vital to the interpretation of any neuromusculoskeletal clinical measure is the comparison between sides. It is essential to compare sides for there is tremendous variation in flexibility of the peripheral nervous system in both the lower and upper quarter.

Objectives: While there has been considerable research on neurodynamics, there has been little research investigating the diagnostic validity of such tests. The purpose of this study was to find out the rate of true positive (sensitivity) Slump Test (modified) in patients with lumbar spine mediated neural symptoms. This research also attempted to find bilateral variability, that is, difference in the angles of knee extension within the range at which the responses were provoked, between the asymptomatic and symptomatic side of the patient.

Methods: Experimental same subject study design with 30 randomly selected patients in the age group of 20-60 years. Sample population was drawn from physiotherapy out-patient department of Gian Sagar Medical College and Hospital and New Hope Physiotherapy Centre, based on inclusion and exclusion criteria. Subjects with lumbar pain and associated neural signs and symptoms (unilateral) went through modified Slump Test (ST1). The test was performed bilaterally, first on asymptomatic and then on the symptomatic side of the patient.

Results: Out of 30 patients, 28 were tested positive with ST1. True positive rate (sensitivity) was calculated using simple percentage. To find difference in the angles of knee extension between asymptomatic and symptomatic side, paired t-test was used.

Conclusion: It was concluded that Neural tissue provocation test (ST1) is highly sensitive in diagnosing the patients with lumbar spine mediated neural signs and symptoms. Significant difference in the angles of knee extension existed between the asymptomatic and symptomatic sides.