Relationship between Femoral Intercondylar Notch Narrowing in Radiography and Anatomical and Histopathologic Integrity of Anterior Cruciate Ligament in Patients Undergoing Total Knee Replacement Surgery

Background: The presence of cruciate ligaments is very important for normal knee kinematics. Knee arthroplastyprostheses, in which these ligaments are maintained, have better kinematics. The aim of the present study was toinvestigate the association between femoral intercondylar notch (FIN) narrowing in radiography and clinical andhistopathologic integrity of anterior cruciate ligament (ACL) in patients undergoing knee replacement surgery.Methods: FIN index was measured in tunnel view radiography of the knees of 102 candidates of knee replacementsurgery. The anatomical status of ACL was also examined during total knee arthroplasty (TKA). ACL was removed andsent for histopathologic examination to assess its degeneration rate. The association between the FIN index and theclinical and histopathological health of ACL was investigated.Results: Among 102 patients with mean age of 69.73 ± 7.81 years , 39 patients (38.32%) had no or torn ACL, 31patients (30.39%) had weak ACL, and 32 (31.37%) had normal ACL. There was a significant association between ageand clinical status of ACL during surgery (P=0.017). There was a significant difference in FIN and ACL health statusduring surgery between the two groups with an index of more and less than 0.252 (P=0.019 and P=0.019, respectively).There was no significant difference in the mean total degeneration score (TDS) of ACL between the two groups with FINmore and less than 0.252 (P=0.816).Conclusion: There was a significant difference between the age and FIN narrowing (less than 0.252) as well as ACLclinical status during surgery. FIN narrowing had no significant effect on the severity of ACL degeneration and there wasno significant difference in the severity of degenerative histopathologic changes between healthy and attenuated ACLs.This indicates that if ACL exists, although apparently attenuated, it has the histologic characteristic of a healthy ligament.Level of evidence: II

Keywords:

anterior cruciate ligament , Femoral intercondylar notch , Knee arthroplasty