ARTHROGENIC QUADRICEPS INHIBITION AND REHABILITATION OF PATIENTS WITHEXTENSIVE TRAUMATIC KNEE INJURIES

1. The relationship between joint damage, quadriceps weakness and arth rogenic muscle inhibition was investigated in eight patients who had s ustained extensive traumatic knee injury. Isometric and isokinetic qua driceps and hamstring voluntary strength, and quadriceps arthrogenic m uscle inhibition during isometric contractions, were measured before a nd after 4 weeks (approximately 100 h) of intensive rehabilitation. 2. Compared with the uninjured leg, before rehabilitation the injured le g had larger amounts of quadriceps arthrogenic muscle inhibition (P < 0.025), quadriceps (P < 0.0001) and hamstring (P < 0.0001) weakness an d severe functional joint instability. There was a negative correlatio n between the amount of arthrogenic muscle inhibition and quadriceps v oluntary contraction force (P < 0.025). 3. After rehabilitation in the injured leg there were small hamstring strength increases (P < 0.05-0 .025), but no overall significant quadricep strength increase. Arthrog enic muscle inhibition was statistically unchanged. Severe functional joint instability was still reported by all patients. 4. Previous stud ies have shown that minimal joint damage evokes relatively less arthro genic muscle inhibition that does not impede rehabilitation. These dat a indicate that greater joint damage is associated with greater arthro genic muscle inhibition, quadriceps weakness and joint instability. Fu rthermore, intensive rehabilitation had little affect on either quadri ceps arthrogenic muscle inhibition or atrophy.