Surgical Treatment of the ACL Injury

It is difficult to diagnose an acute anterior cruciate ligament (ACL) injury through physical examination because patients cannot relax their muscles due to pain. Patients with an acute ACL injury are examined by comparing the affected side with the uninjured side. The Lachman and pivot shift tests are positive with full muscle relaxation. Stress film using a KT 1000 or 2000 arthrometer shows a difference of more than 3–5 mm between the knees of patients with an acute ACL injury (the knee ROM is nearly within the normal range, and the swelling has subsided). It usually takes 2–3 weeks for the swelling to subside and for a nearly full range of motion (ROM) to be achieved. If ACL surgery is performed too early, arthrofibrosis will occur, and the knee joint will become stiff. However, if there is a locked meniscus bucket handle tear or knee dislocation or subluxation, surgery should be performed as early as possible for reduction. When we perform ACL remnant preservation and wrap over the graft, healing of the reconstructed ACL graft, especially synovialisation, will be much better (Figs 3.36 and 3.37). According to Nakase et al., the rounded rectangular femoral tunnel ACL reconstruction (RFTR) group had a larger femoral tunnel area than the anatomic single-bundle ACL reconstruction (ASBR) group (average area: 53.1 ± 4.0 mm² vs. 46.1 ± 7.0 mm², P < 0.01). The RFTR group had better anteroposterior stability and higher Lysholm scores than the ASBR group (average side-to-side difference for anterior tibial translation, 0.6 ± 0.8 mm vs. 1.6 ± 1.4 mm; P < 0.01; average Lysholm score, 98.5 ± 2.1 vs. 97.5 ± 3.5; P < 0.01). There were significant differences in rotational laxity between the groups (negative pivot shift, 94.3% vs. 92.3%; P < 0.01). No significant difference was noted in the IKDC subjective score between the two groups. The surgeon should carefully check for combined injuries, such as posteromedial or posterolateral instability (PLRI) and meniscal injury. Neglecting PLRI and other combined injuries will result in failure of the ACL reconstruction.