No increased rate of cyclops lesions and extension deficits after remnant-preserving ACL reconstruction using the sparing technique

BACKGROUND: Remnant-preserving anterior cruciate ligament reconstruction (ACLR) should have advantages for postoperative remodeling and proprioception. However, it has been suggested that the larger diameter of the graft tends to lead to impingement phenomena with a higher rate of cyclops lesions. The aim of this work was to find out whether the remnant-preserving ACLR actually leads to an increased rate of range of motion restraints compared to the remnant-sacrificing technique. METHODS: Patients, who fulfilled the inclusion criteria, were followed up for one year after surgery. The primary endpoint was arthrolysis due to extension deficit or cyclops syndrome. Secondary outcome measures were pain (NRS), knee function (KOOS), patient satisfaction and return to sports rate. RESULTS: One hundred and sixty-four patients were included in the study, 60 of whom received the “remnant augmentation” procedure (group 1). In the remnant augmentation group, one cyclops resection was performed, whereas in the non-remnant augmentation group three cyclops lesion resections had to be performed (odds ratio 0.6). There was no difference between the groups in pain (NRS) and knee function (KOOS) and patient satisfaction. The return to sports rate after one year was higher in the remnant augmentation group. CONCLUSIONS: Patients who have undergone the sparing “remnant augmentation” ACLR have no increased risk of cyclops lesion formation or extension deficit in the first year after surgery. An improvement of the proprioceptive abilities by remnant augmentation ACLR should be investigated in further studies. LEVEL OF EVIDENCE: III (prospective cohort study).