Evaluation of Clinical Tests in Detecting Nerve Regeneration

There is not a perfect clinical nerve regeneration assessment test. Tinel’s test is an acknowledged test for clinical evaluation of nerve regeneration, but has significant imperfections. Therefore, there is great incentive to develop perfect clinical tests. Scratch collapse test and tender muscle sign have been described recently as valuable nerve entrapment provocative tests. In this study, scratch collapse test and tender muscle sign were used for evaluation of nerve regeneration and compared to Tinel’s test and electrodiagnostic study.
Scratch collapse test and tender muscle sign were prospectively compared to Tinel’s test and electrodiagnostic study every 3 months post operation in 20 patients underwent nerve repair. Positive and negative frequency, sensitivity, specificity and coefficient agreement of each test were calculated.
Findings: Sensitivity of Tinel’s test, tender muscle sign, scratch collapse test, and electrodiagnostic study was 70%, 60%, 50%, and 80%, respectively. Specificity of Tinel’s test, tender muscle sign, scratch collapse test, and electrodiagnostic study was 80%, 90%, 60%, and 80%, respectively. The highest positive and negative predictive values were related to tender muscle sign and Tinel’s test, respectively. The scratch collapse test had the lowest positive and negative predictive values, sensitivity, and specificity.
Tinel’s test and tender muscle sign had the most sensitivity and specificity, respectively; routine application of these two tests is recommended for evaluation of nerve regeneration. But, scratch collapse test has not required sensitivity and specificity to be used routinely for evaluation of nerve regeneration process.