A comparison of percutaneous and mini-open techniques of Achilles tenotomy: an experimental study in rats.

Purpose: To investigate the effect of Achilles tenotomy performed percutaneously and by mini-open methods on tendon healing and final strength.

Materials And Methods: In two groups, each consisting of 14 rats, percutaneous and mini-open techniques in Achilles tenotomy were compared in terms of biomechanical, histological and gross properties.

Results: In the gross evaluation, it was observed that an obvious thickening and adhesion to the subcutaneous tissue of the healing tendon were observed in nearly all rats in which the mini-open technique was performed. In the biomechanical analysis, there was no significant difference between percutaneous and mini-open groups and between operated and intact Achilles tendons in both groups, in terms of tendon strength (P > 0.05). In the histological evaluation, irregularity in the parallel pattern of the collagen fibres, emergence of a non-specific collagenous tissue formation and infiltration of mild mononuclear inflammatory cells were reported. These changes were more marked in the rats in which the percutaneous technique was performed.

Conclusion: Mini-open technique for Achilles tenotomy may be considered as an alternative method of treatment to apply the tenotomy technique in a secure way.

Clinical Relevance: There are two basic advantages of Achilles tenotomy performed by the mini-incision open technique: (1) a complete tenotomy is guaranteed, as it has to be in the original Ponseti technique, (2) iatrogenic neuro-vascular injury risk is nearly completely avoided due to the subparatenon exploration of the tendon and direct visual observation during the transection. The mini-open technique may only be used in cases in which a vascular compromise is clinically suspected or confirmed by Doppler ultrasonography and/or arteriography. On the other hand, the technique may be performed in all cases routinely by the choice of the surgeon.