Review Question - QID 3841

This patient presents with a chronic Achilles tendon rupture. The most appropriate treatment of this injury would be flexor hallucis longus (FHL) tendon transfer with sliding V-Y advancement of the gastrocnemius-soleus complex aponeurosis. The FHL is supplied by the tibial nerve and inserts on the base of the distal phalanx of the 1st digit.

Achilles tendon ruptures diagnosed over 3-4 weeks after injury are considered chronic in nature and usually necessitate surgery to restore tendon normal resting tension. Defects smaller than 3cm are amenable to direct repair or adding some form of local tissue augmentation like a V-Y gastroc advancement. For ruptures with defects over 3cm, the muscle is generally weak and scarred, requiring reconstructions utilizing tendon transfers in addition to local tissues advancement. The Flexor Hallucis Longus tendon is the most common transfer performed, but Peroneus Brevis tendon transfers are done but to a lesser degree.

Myerson et al. reviewed Achilles tendon ruptures. They state that the FHL tendon transfer is typically stronger than the peroneus brevis as its axis of pull replicates that of the Achilles tendon and the muscle activates 'in phase' with the gastrocnemius-soleus complex. For these reasons FHL transfer is ideal for reconstructions.

Padanilam reviewed the diagnosis and management of chronic Achilles ruptures. Diagnosis is often apparent clinically but MRI proves valuable in gauging the gap needed to be restored. Freeing all tendon stump adhesions and applying manual traction may help gain tendon excursion. Fascial turndown flaps, VY advancements and/or FHL tendon transfers may be required depending on the chronicity.

Illustrations A and B from Padanilam et al demonstrates a V-Y advancement and an FHL-augmented Achilles repair respectively.

Incorrect Answers:
Answer 1: Flexor Hallicis Brevis inserts on the proximal phalanx.
Answer 2: Extensor Hallucis Longus inserts on the dorsum of the distal phalanx and is innervated by the deep peroneal nerve.
Answer 3: Peroneus Brevis inserts on the 5th metatarsal.
Answer 4: Tibialis Anterior inserts on the on the medial cuneiform and 1st metatarsal base.