Is anterolateral ligament rupture a reason for persistent rotational instability after anterior cruciate ligament...

The aim of the present study was to evaluate the clinical role of anterolateral ligament (ALL) rupture and its impact on rotational stability by comparing the clinical results and rotational stability between reconstructed anterior cruciate ligament (ACL) with intact ALL knees and reconstructed ACL with ALL injured knees.

A total of 69 patients who had undergone surgery for ACL reconstruction and had received a minimum of two years of follow-up were included. Patients were divided into two groups with respect to the presence of ALL rupture on knee magnetic resonance imaging. Patients were assessed preoperatively and at final follow-up with physical examination findings and functional outcomes. Rotational stability was measured by a non-invasive rotameter-like device at the final follow-up at different torque values of 5 Nm (newton metres), 10 Nm and 15 Nm, and compared between the two groups.

The ALL was considered to be ruptured in 45 cases, named Group I (65.2%). The ALL was considered to be intact in 24 cases, named Group II (34.8%). No significant difference was found between the groups regarding the improvement of the clinical scores and physical examination findings (P > 0.05). Group I showed significantly higher internal rotation difference compared with Group II in all torque values (P < 0.05).

The difference found on rotational measurement is possibly under the value of minimal clinical important difference and does not have a clinical effect, therefore ALL reconstruction is not recommended as a standard treatment in all patients.