In a flexor digitorum longus transfer for hammertoe, under which condition would it be unlikely to succeed?

In a flexor digitorum longus transfer for hammertoe, under which condition would it be unlikely to succeed?

• A. When there is no spasticity of the muscle. I.E. T10 paralysis.
• B. Full length rigid or semirigid orthotic.
• C. The metatarsal head must be plantarflexed.
• D. It requires a flexible toe extension.

Answer: (D)

The key idea is that a flexor digitorum longus transfer for hammertoe relies on the toe having a flexible extensor mechanism. The transfer repositions the FDL to create a plantarflexion moment that helps straighten the toe, but this only works if the toe can still extend and be guided into a corrected alignment. If the toe extension is not flexible—i.e., there is a fixed flexion deformity or rigid extension—the transferred tendon cannot achieve durable correction, so the procedure is unlikely to succeed. Other factors mentioned don’t address this crucial limitation; the essential predictor is the ability of the toe to extend flexibly after correction.

The key idea is that a flexor digitorum longus transfer for hammertoe relies on the toe having a flexible extensor mechanism. The transfer repositions the FDL to create a plantarflexion moment that helps straighten the toe, but this only works if the toe can still extend and be guided into a corrected alignment. If the toe extension is not flexible—i.e., there is a fixed flexion deformity or rigid extension—the transferred tendon cannot achieve durable correction, so the procedure is unlikely to succeed. Other factors mentioned don’t address this crucial limitation; the essential predictor is the ability of the toe to extend flexibly after correction.