ROLE OF SCAPHOID IN THE ABDUCTION AND ADDUCTION MOVEMENTS OF WRIST JOINT

Abstract

Background: Being a carpal bone scaphoid has an important role in wrist movements. Wrist joint is a synovial modified ellipsoid joint where movements like flexion, extension and adduction, abduction take place around two axes (transverse and antero-posterior). These movements at the wrist joint are associated with considerable range of movements at the mid carpal joint, as same group of muscles act on both of these joints.

Methodology: A study has been done amongst 120 persons at the tertiary care hospital during the period from 2006-07 to detect the important movements of scaphoid bone specially during the abduction and adduction of wrist joint (which occur in association with the intercarpal joints) and also to detect whether such movements have any speciality in the population.

Results: In fully abducted position, it was 45^o among 53.3% subjects and the average among all the subjects was 60^o. So, the degree of abduction was 30^o. The extent of movement was more in adduction (ie, 1.90 cm - 1.03 cm = 0.87 cm) than in abduction (ie, 1.03 cm - 0.72 cm = 0.31cm).

Conclusion:  It was found in this study that the scaphoid acts as a link bone between the two rows of carpal bones and prevents the buckling of midcarpal joint especially of the capitato- lunate joint interface.