It is essential to assess the functional status of patients with surgically reconstructed and rehabilitated anterior cruciate ligaments prior to discharge. This study established a testing paradigm for functional force production and absorption. Data were obtained from 100 healthy subjects for maximal hops, controlled leaps, and hopping and leaping symmetry. Only 10% of symptomatic patients met maximal hopping criteria, while 15% achieved controlled leaping norms. Ninety-five percent of these patients failed to reach both hopping and leaping symmetry norms. Asymptomatic patients were 63% successful in meeting hopping criteria, and 57% were successful in meeting leaping criteria. Hop symmetry and leap symmetry were achieved at rates of 70% and 60%, respectively. The performance of both groups fell significantly below that of normal subjects (p < .05). Data suggest that this protocol does accurately assess functional and dysfunctional knees, and that force absorption may be more critical than force production in the determination of functional capacity.

J Orthop Sports Phys Ther. 1997;26(4):184-191.

Key Words: anterior cruciate ligament, function, deceleration, rehabilitation