FOREARM ANTHROPOMETRY AND ELBOW VIBRATIONS OF TENNIS PLAYERS WITH AND WITHOUT ELBOW PAIN 704

Abstract

One of the many factors attributed to the development of “tennis elbow” or lateral epicondylitis is the transfer of racket vibrations onto the forearm. Heavier subjects tend to have reduced arm vibrations, but no attempt has been made to study the forearm physical characteristics and the vibrations transferred to the elbow of players with (WP) and without elbow pain (WOP). Twenty-three female players of the same skill level [14 WOP and 9 WP] were tested using an ENTRAN uniaxial accelerometer encased in balsa wood and fastened using an elastic band over the lateral epicondyle, aligned with the humerus. Dunlop Super Revelation rackets (stiff) with different grip sizes and equal string tension (275 N) were used in the study. A ball machine was used to ensure proper ball velocity (11.1 ± 1.4 m/s) and alignment. Each subject performed 5 off-center (10 cm) and 5 on-center static backhand trials. The anthropometric variables taken were (age, height, grip size, hand size, forearm circumference and length, wrist circumference and range of motion, and grip strength. Pearson Product moment correlation's and t-test's for independent means were used to analyze the data. Elbow peak accelerations immediately after impact were.48 ±.10 and.59 ± 1.5 g for the center and the off-center hits, respectively (p<.05). No significant correlation's were found between the off-center and center peak accelerations and the anthropometric variables. Although not significant, there were strong correlation's between body weight and center and off-center peak accelerations[r=-.63 & -.50 WP, r=-.48 & -.48 WOP]. Age was the only significant factor between the WP ([horizontal bar over]x = 45) and the WOP ([horizontal bar over]x = 39). These results suggest that forearm anthropometric differences are not a significant factor in the transmission of racket vibrations at the lateral epicondyle of people with elbow pain.