Gohil S, Annear PO,Breidahl W.
British Journal of Bone and Joint Surgery 2007; 89-B;9:1165-1171
There are now a number of ways to perform arthroscopic ACL reconstructions. One factor which determines the outcomes is the fixation of the grafts and the potential for the graft to revascularise. The graft is at it’s weakest when the graft is revascularising and so rehabilitation tends to depend on when the graft has revascularised. Conventional arthroscopic reconstructions take up to 6-16 weeks to revascularise.
The authors hypothesised that if a minimal debridement is performed during the ACL reconstruction particularly of the ACL stump and in the intercondylar notch, then this would lead to a quicker revascularisation and therefore rehabilitation.
In this randomised prospective trial, 25 patients had a conventional clearance of the intercondylar notch and 24 had a minimal debridement technique. All patients had an arthroscopic double hamstring harvest (semi-tendinosus and gracilis) ACL reconstruction.
One patient from the conventional group had a graft rupture and 2 from the minimal debridement group had fixation failures. Therefore, 24 in the conventional group and 22 in the minimal debridement group underwent serial MRI at 2,6 and 12 months post-operatively to study for revascularisation of the ACL graft. These patients were also scored using the International Knee Documentation Committee (IKDC) scoring system for patient satisfaction and outcome and all knees were clinically assessed with the KT-1000 arthrometer. All assessments were made by clinicians who were blinded to the surgical techniques, thus reducing bias.
A significantly earlier revascularisation was noted in the minimally debrided group, which appeared at 2 months following surgery and reduced by 6 months as opposed to 6 months and 12 months respectively in the conventional group. The revascularisation was quantitatively measured using signal intensity changes on the MRI. It was also noted that there was no significant increase in Cyclops lesions in the minimal debridement group as a result of less clearance of the notch and that the clinical results between the two groups were equivocal at 12 months.
The authors speculate that by minimal debridement of the notch and ACL remnants this leads to quicker revascularisation and therefore strength of graft. This in turn could allow can allow an accelerated knee rehabilitation programme, although this was not demonstrated in their study.