[Less invasive turn-down flap tendinoplasty in chronic Achilles tendon rupture].

Objective: Bridging the defect in chronic ruptures of the Achilles tendon via a turn-down flap of the aponeurosis sparing the skin of the rupture zone.

Indications: Chronic Achilles tendon rupture with a defect distance ≤ 6 cm.

Contraindications: Extended Achilles tendon defect interval ≥ 7 cm, chronic wounds or infections near the surgical approach, higher degrees of arterial or venous malperfusion, complex regional pain syndrome.

Surgical technique: Dorsomedial surgical approach proximal to the rupture zone, splitting of the crural fascia, loading of the distal Achilles tendon stump with a nonresorbable augmentation suture using the Dresden instrument, preparation of the turn-down flap of the aponeurosis securing the turning point with a catching suture. Transfer of the turn-down tendon flap under the skin bridge and suture to the distal tendon stump tying the augmentation suture under adequate pretension simultaneously closing the gap in the aponeurosis. Alternative technique: free advancement of the autologous tendon graft.

Postoperative management: Anterior splint in 20° of plantar flexion, consecutive mobilization and rehabilitation similar to the percutaneous technique in acute Achilles tendon rupture with the Dresden instrument. Lower leg orthosis with 20° of plantarflexion for 8 weeks, then stepwise reduction of the heel height. Physiotherapy beginning from the 2nd postoperative week, active full-range of ankle motion from 6 weeks after surgery.

Results: In general, worse results than in percutaneous reconstruction of acute Achilles tendon injuries. Despite this, high degrees of patient satisfaction with a low rate of postsurgical complications and good functional outcome with admittedly poor data availability. Relevant increase of plantar flexion strength depending on the amount of degeneration of the triceps surae muscle.