Flexor hallucis longus tendinitis

What is FHL Tendinopathy?

The FHL tendon plantar flexes the hallux or big toe. It originates from the fibula bone, runs along the inside of the ankle and inserts into the plantar big toe. Tendinopathy is now the word of choice rather than 'tendinitis'. When examining affected tendons from biopsies, researchers have commonly found little to no inflammation in the tendon. Commonly FHL tendinopathy will present with pain and/or discomfort around the medial (inner) ankle and foot.

What Causes It?

FHL tendinopathy is typically an overuse injury and is very common in ballet dancers, who repetitively go from flat to en pointe position where extreme plantarflexion is required. Poor intrinsic foot muscle control can cause gripping or curling with the toes and therefore overusing the long flexor tendon. The FHL tendon can also be aggravated by 'forcing turnout' and rolling in of the foot.


  • Short term avoidance of aggravating activity
  • Physical therapy including soft tissue release, low level laser therapy, taping
  • Manual mobilisation of subtalar joint
  • Footwear review
  • Orthotic therapy
  • Examination and strengthening of hip abductors, intrinsic foot control
  • Examination and correction of athletic technique
  • In extreme cases surgical release of the tendon is necessary