Injury to the anterior cruciate ligament (ACL) is thought to disrupt joint afferent sensation and result in proprioceptive deficits. This investigation examined proprioception following ACL reconstruction. Using a proprioceptive testing device designed for this study, kinesthetic awareness was assessed by measuring the threshold to detect passive motion in 12 active patients, who were 11 to 26 months post-ACL reconstruction, using arthroscopic patellar tendon autograft (n=6) or allograft (n=6) techniques. Results revealed significantly decreased kinesthetic awareness in the ACL reconstructed knee versus the uninvolved knee at the near-terminal range of motion and enhanced kinesthetic awareness in the ACL reconstructed knee with the use of a neoprene orthotic. Kinesthesia was enhanced in the near-terminal range of motion for both the ACL reconstructed knee and the contralateral uninvolved knee. No significant between-group differences were observed with autograft and allograft techniques.