Large ACL graft diameter and knee stability after ACL reconstruction

Abstract

Introduction Novel surgical techniques allow to obtain optimal ACL graft size, but there is little data on how the stability of the knee joint and the patient's well-being in the postoperative period are dependent on the size of the graft. Aims and Objectives To determine how the ACL graft diameter and knee stability affect patient well-being after ACL reconstruction. Materials and methods The study included 62 randomly selected patients who underwent primary ACL reconstruction using semitendinosus and gracilis tendon autografts. Patients were assessed 6 months after surgery based on the IKDC system and Genourob (GNRB) knee mobility study. The patients were divided into 5 groups according to obtained ACL graft diameter: Graft diameter groups: Group 1 - graft size - 12 mm; Group 2 - graft size - 11 mm; Group 3 - graft size - 10 mm; Group 4-– graft size - 9 mm; Group 5 - graft size - 8 mm. The GNRB system was used to assess knee joint mobility in operated and healthy knee joints by applying an equal force of 134N to both knees. All patient knee joints were assessed 6 months post-surgery using the GNRB system, the results of which were compared with ACL graft diameter and IKDC scores. Results After comparing the data 6 months after ACL reconstructions, we found that 12mm diameter ACL graft was obtained in 7 patients, 11 mm in 9 patients, 10 mm in 26 patients, 9 mm in 14 patients, and 8 mm in 6 patients. When evaluating the stability of knee joints using the GNRB system, a difference of 3 mm in 6 patients. IKDC questionnaire scores 6 months after operation: 60–70 – 10 patients; 70-80 - 13 patients; 80 to 90 - 15 patients; 90-100 - 23 patients. The highest mean IKDC score (92.55) was established in the 12 mm diameter graft group, 76.6 in the 11 mm group, 84.5 in the 10 mm group, 82.5 in the 9 mm group, 73.1 in the 8 mm group. Patients who scored 60-70 in the IKDC questionnaire mean GNRB shift was 1,1 mm, mean graft size - 9,6 mm; IKDC 70-80 - GNRB 1,3 mm mean graft size - 10,1 mm; IKDC 80-90 - GNRB - 0,1 mm, mean graft size - 9,8 mm; IKDC 90-10- GNRB 0,5 mm, mean graft size - 10,1 mm. GNRB knee stability study showed the highest IKDC score for patients with the lowest, and particularly negative displacement compared to a healthy knee joints: mean 3 mm GNRB group (p < 0.05). Conclusions Based on our data, we found that ACL graft diameter of 8mm and less was associated with poorer well-being and highest GNRB stability scores ensure the best well-being 6 months after ACL reconstruction, when evaluating patient well-being using the IKDC questionnaire.