Aims: ACL lesion is one of the most frequent event in sport injuries. It is generally a complete lesion which does not evolve to a spontaneous healing. In particular, after non surgical treatment, ACL often repairs on PCL with a residual articular laxity. A healing response technique has been described to treat ACL incomplete tears in skeletally immature athletes. Our technique is based on microfractures next to the ACL femoral insertion to obtain a scar reinforcement thanks to the action of mes-enchymal stem cells.

Methods: The authors report their experience using the same surgical technique and rehabilitation protocol in patients selected by type of lesion, age and time from injury.

The authors selected for the study young-middle age active patients, with incomplete ACL lesion: 27 patients (mean age of 23 years) have been evaluated, inclusion criteria was Lachman test < 1 cm, negative Jerk test and a proximal partial tear of ACL on MRI. Before and after surgery the patients have been evaluated using KT1000, MRI, clinical examination and Lysholm score with a 3 years average follow up.

Results: Clinical examination showed a significative improvement in Lysholm score from 63 to 85 and a minor anterior tibial translation measured with KT1000 (from a mean difference between the two legs of 5 mm preoperatively to 2 mm postoperatively). In only one case the ACL didn’t seem to heal and was necessary the traditional reconstruction. MRI at one year pointed out a reparative healing in almost all cases.

Conclusions: according to these results the healing response procedure can restore a subjective and objective stability and knee function, with proper patient selection and strictly following the rehabilitation protocol despite of age and time of lesion.