Sensibilité de l’hémipulpe radiale de l’index — étude des tests de Semmes-Weinstein versus Cochet-Bonnet chez 25 sujets sains

Abstract

In the presence of a wound to the palm, several methods of evaluation of the cutaneous sensitivity were proposed to search for sensory deficits. Some authors have shown that the sensitivity and specificity of any other test do not reach 100%. Most authors consider that any hand wound in the vicinity of a nerve path must be surgically explored. The purpose of this work was to verify whether the Cochet-Bonnet corneal sensitivity test had a lower cutaneous pulp sensitivity threshold than the Semmes-Weinstein monofilament test. The series included 25 healthy adult subjects. The average age was 30 years old. All were right-handed except one left-handed. None had a history of a medical or surgical pathology of upper limbs. The protocol consisted of evaluating the tactile cutaneous sensitivity threshold of the radial collateral hemi-pulp of the index finger by an independent observer using two tests, the Semmes-Weinstein esthesiometer and the Cochet-Bonnet. The Semmes-Weinstein test consisted of determining the finest monofilament perceived from a kit of 20 calibrated monofilaments from 0.0045 to 447.0 g. The monofilaments were applied one after the other perpendicularly to the hemi-pulp so that the wire bends slightly for 1.5 seconds. The Cochet-Bonnet test consisted of determining the longest perceived monofilament from a 12-length calibrated pen from 0.006 to 0.618 g. The monofilament was applied perpendicularly to the hemi-pulp so that the thread bent slightly for 1.5 seconds. The sensitivity threshold of the radial hemi-pulp of the index was lower with the CB test than with the SW test. The average cutaneous sensitivity threshold of the hemi-pulps of our series was 0.0388 g, which corresponds to the threshold of 0.035 g before 35 years found in the literature. Our results show that in healthy subjects, the threshold of sensitivity of the radial hemi-pulp of the index is lower with the Cochet-Bonnet monofilament test than with the Semmes-Weinstein monofilament test. The material needed to carry out the Cochet-Bonnet monofilament test is cheaper (424 €) and less cumbersome (1 monofilament) than that required for the Semmes-Weinstein monofilament test, which costs more (901 €) and is bulkier (20 monofilaments). It remains to test the sensitivity and specificity of the CB test on wounds of the palm to check the absence of nerve damage.