Addition of test components during neurodynamic testing: Effect on range of motion and sensory responses

Study Design: Single session, repeated-measures design. Objectives: To analyze the impact of different components of the neural tis sue provocation test for the median nerve (NTPT1) on the range of motion (R OM) of the elbow and wrist and the sensory responses elicited by the test. Background: The assessment of minor peripheral nerve injuries by neurodynam ic tests is becoming more integrated in physical therapy practice. The infl uence of different test components on the nervous system has been analyzed in numerous in vitro studies, but in vivo studies are still lacking. Methods and Measures: Five test variations were performed on 35 asymptomati c men (23.5 +/- 2.3 years). Elbow extension was performed (1) without addit ional components (NTPT1(NEUTRAL)), (2) with wrist extension (NTPT1(WE)), (3 ) with cervical contralateral lateral flexion (NTPT1(CLLF)), and (4) with b oth wrist extension and cervical contralateral lateral flexion (NTPT1(WE+CL LF)). In the fifth variant, the wrist was extended from a preloaded positio n (WENTPT1). The range of elbow and wrist extension when a submaximal disco mfort was elicited was measured with 2 electrogoniometers. Results: The addition of each test component resulted in a significantly re duced ROM (NTPT1(NEUTRAL): 179.5 +/- 8.8 degrees, NTPT1(WE): 169.0 +/- 13.9 degrees, NTPT1(CLLF): 154.7 +/- 13.2 degrees, NTPT1(WE+CLLF): 143.9 +/- 16 .1 degrees; WENTPT1: 67.1 +/- 11.0 degrees). Sensory responses were predomi nantly evoked at the region of the added component. Conclusions: The different test components, whose mechanical influence on t he nervous system has been demonstrated in anatomical studies, also have an effect on joint ROM and sensory responses during neurodynamic testing, whe n individually or simultaneously added. If the nerve bedding is elongated t hroughout its whole length, the available ROM is markedly reduced and senso ry responses can be elicited throughout the entire arm.