Another ACL graft option

Artificial ligaments in anterior cruciate ligament have had a bad reputation for a long time. So much so that they have been almost totally dismissed as an option in the USA and Europe. No reports at international meetings or in journals report on their outcomes. Until now that is and the April 2010 edition of the Arthroscopy journal.

A Chinese group Kai Gao et al report a multicentre 3 to 5 year follow up of ACL reconstruction using the Ligament Advanced Reinforcement System. LARS artificial ligament is a biomimic scaffold of artificial ligament made of polyester (polyethylene terephthalate [PET]) fibres. The intra-articular portion of LARS artificial ligament is composed of longitudinal external rotation fibres, and the left knee and right knee are separately designed, as clockwise or counter clockwise, respectively.

The graft is used as a scaffold when a stump of the torn ACL is present. The graft is placed through the retained stump. The study showed that LARS artificial ligament as a nondegradable scaffold in vivo could induce the growth of autologous collagen tissue and neoligament formation, which would increase the strength of LARS artificial ligament, avoid the abrasion of ligament fibres, and extend the longevity of the ligament. Basically a neoligament grows from the stump to surround the artificial graft.

This is not a controlled clinical trial. It is a therapeutic case series with a level 4 Level of Evidence. The results are similar to other case series using standard techniques. The femoral tunnel was drilled through the tibial tunnel unlike present techniques where the femoral tunnel is drilled through the anteromedial portal. There is not enough evidence in this article to change clinical practice.

Nevertheless it is an interesting study which should stimulate surgeons to have a second look at augmentation devices and see if they have a role. The obvious major advantage is they would avoid the need to take a graft from the patient, shortening operating time and reducing morbidity.

It is always interesting when someone challenges the accepted doctrine.