Introduction: Functional knee braces are commonly used after ACL reconstruction surgery. However, the study to evaluate the contributions of the knee brace is a few. We investigated the effects of knee brace prospectively.

Methods: From 1993 to 1996, forty eight patients with 48 knees were treated with autogenous ACL reconstruction. The patients were randomly divided to two groups; twenty five patients (group B) used knee brace for one year and the other 23 patients (group NB) were free from bracing. Forty two patients were followed over two years. The averaged follow-up period was 27 mouths and the averaged age at surgery was 24.5 years. The semitendinosus and the gracilis tendon in the contralateral side were used to make triple looped (six strands) substitute. Bone tunnels were made at the appropriate site using inside-out technique under arthroscopy assistance. Polyester meshes were connected to the substitute and fixed to the tibia and femur with staples after grafting through the bone tunnels. The same rehabilitation protocol was used for both patients group. Functional outcomes were evaluated with IKDC score.

Results: The rate of category A, B ,C and D in the group B were 52%, 44%, 4% and 0%. Those in the group NB were 65%, 26%, 9% and 0% respectively. There is not any Statistically significant difference between the two groups.

The joint stability were measured with stress x-p using TELOS device. The anterior displacement ratio improved from 73±4.9%(mean ±sd) to 64±4.6% in group B, and it also improved from 72±4.0% to 62±2.9% in group NB. Statistically significant improvements were obtained after surgery in both the two groups, however, no statistically significant difference of stability were found between the two groups.

Conclusion: These results suggest that the functional knee brace is not indispensable when the hamstring substitute is used for ACL reconstruction with secure fixation methods.