Acute Posterior Ankle Pain in Acute Posterior Ankle Pain in a High School Football Playera High School Football Player

John Hardin, MA, CSCS, ATCJohn Hardin, MA, CSCS, ATC

Personal Data/HistoryPersonal Data/History A 16 y/o male varsity football player A 16 y/o male varsity football player

c/o acute postero-medial pain in the c/o acute postero-medial pain in the right ankle.right ankle.

The athlete was cutting on a plantar The athlete was cutting on a plantar flexed foot, felt a pop, and then flexed foot, felt a pop, and then experienced immediate pain.experienced immediate pain.

The athlete continued to compete with The athlete continued to compete with discomfort.discomfort.

Physical Signs and SymptomsPhysical Signs and Symptoms The athlete presented with exquisite The athlete presented with exquisite

tenderness on palpation of postero- tenderness on palpation of postero- medial aspect of the talus and medial medial aspect of the talus and medial malleolusmalleolus

No tenderness was present over the No tenderness was present over the lateral aspect of the ankle lateral aspect of the ankle

Full ROM w/ pain in terminal plantar Full ROM w/ pain in terminal plantar flexion flexion

Past HistoryPast History

Athlete had fractured his os Athlete had fractured his os trigonum on the contralateral ankle trigonum on the contralateral ankle in a non-sports related injury in a non-sports related injury approximately one month earlier.approximately one month earlier.

Physical Signs and SymptomsPhysical Signs and Symptoms

No instability with ligament laxity No instability with ligament laxity teststests

Manual muscle tests (especially DF Manual muscle tests (especially DF and PF) were limited by pain. and PF) were limited by pain.

A biomechanical evaluation revealed a A biomechanical evaluation revealed a forefoot varus.forefoot varus.

Differential DiagnosesDifferential Diagnoses Achilles tendon strainAchilles tendon strain Flexor hallucis longus strainFlexor hallucis longus strain Tibialis posterior strainTibialis posterior strain Deltoid ligament (post. tibio-talar) sprainDeltoid ligament (post. tibio-talar) sprain Os trigonum fxOs trigonum fx Osteochondral lesion of talusOsteochondral lesion of talus Posterior tibio-talar impingement Posterior tibio-talar impingement Posterior talo-calcaneal ligament avulsionPosterior talo-calcaneal ligament avulsion

Diagnostic Imaging/ Diagnostic Imaging/ Laboratory TestsLaboratory Tests

X-rays revealed X-rays revealed a complete a complete fracture of the fracture of the os trigonum of os trigonum of the talus.the talus.

Clinical CourseClinical Course A course of conservative management A course of conservative management

including walking boot immobilization including walking boot immobilization for the ankle (neutral position) for for the ankle (neutral position) for three weeks.three weeks.

Following the removal of the walking Following the removal of the walking boot, he performed pool workouts boot, he performed pool workouts progressing to running and cutting. progressing to running and cutting.

Clinical CourseClinical Course

Athlete was fitted with orthotics to Athlete was fitted with orthotics to correct his forefoot varus. correct his forefoot varus.

He was also given stretching and He was also given stretching and strengthening exercises with emphasis strengthening exercises with emphasis on his posterior ankle/calf musculatureon his posterior ankle/calf musculature

DiscussionDiscussion Os trigonum =Accessory bone found just Os trigonum =Accessory bone found just

posterior to talusposterior to talus Present in 50% of normal feetPresent in 50% of normal feet It may fuse w/ lateral tubercule or remain as It may fuse w/ lateral tubercule or remain as

separate ossicleseparate ossicle Os trigonum is round, oval, or triangular and of Os trigonum is round, oval, or triangular and of

variable sizevariable size It may be considered a non-united portion of It may be considered a non-united portion of

the lateral tubercle.the lateral tubercle.

Deviated From ExpectedDeviated From Expected

The os trigonum is a “normal variant” of The os trigonum is a “normal variant” of bony ankle anatomybony ankle anatomy

The os trigonum fracture can be easily The os trigonum fracture can be easily confused with other posterior pathologies.confused with other posterior pathologies.

Lateral x-rays to confirm diagnosis; Lateral x-rays to confirm diagnosis; Continuing pain w/ neg. x-ray, a bone scan Continuing pain w/ neg. x-ray, a bone scan may be a useful evaluative test.may be a useful evaluative test.

Thank youThank you