AN INVESTIGATION OF THE SHORT-TERM EFFECT OF EXERCISE ON THE KNEE-JOINT BY MEANS OF COMPUTER-ASSISTED AUSCULTATION

Although a number of authors have reported the various long term effec ts of both immobilisation and exercise on the knee joint, few have att empted to quantify the process of change by non-invasive in-vivo means . This study explored the usefulness of an innovative application of a uscultation as a tool for non-invasive monitoring of degenerative or r egenerative processes within the knee. A structured appraisal of five different component modes of activity (static load, kinetic load, stat ic rest, kinetic rest, seated) was carried out to determine their seve ral influences on the dynamics of the knee joint. Each mode of activit y was responsible for a distinct alteration to the characteristics of patellar vibration quantified by amplitude, shape and frequency variab les. Loading the knee joint alters its tribology such that patellar vi bration is more frequent and of greater amplitude (19 . 23 Hz, 0 . 86 ms(-2)) than is the case following kinetic rest by continuous passive motion (CPM) (2 . 85 Hz, 0 . 13 ms(-2)). Furthermore, the effect of st atic load is so pronounced that it has zero correlation in terms of vi brational amplitude with that of any previous activity. The amplitude caused by CPM, however, is well correlated (R = 0 . 73), though greatl y reduced from that caused by activity immediately prior to CPM which suggests that CPM facilitates recovery of the joint from the effects o f previous activity.