Patient History

63-year-old man complaining of pain and swelling of the right lateral ankle for 6 months.

Findings

SKELETAL/BONES:

Giant hypertrophic elongated lateral calcaneal peroneal tubercle, with associated reactive/stress related osteoedema.

No further stress related osteoedema. No micro- or macro-trabecular fracture. No stress fracture. No aggressive osseous abnormality.

Incidental note is made of a 6 mm os peroneus (embedded within the cuboid tunnel segment of the peroneus longus). No osteoedema of the os peroneus.

ARTICULATIONS:

Tibiotalar joint/talar dome: No osteochondral defect of the talar dome or tibial plafond.

Ankle mortise/syndesmosis: The ankle mortise is in anatomic alignment. No syndesmosis widening.

Chopart joint: Unremarkable.

Midfoot/hindfoot: Marked degenerative arthrosis of the 2nd tarsometatarsal joint and mild degenerate arthrosis of the 3rd tarsometatarsal joint. No fracture or injury of the anterior calcaneal process.

LIGAMENTS:

High ankle: Intact.

Low ankle: Intact.

Subtalar/Chopart: Intact.

TENDONS:

Diffuse moderately to markedly hypertrophic tendinosis with tenosynovitis involving the supramalleolar, juxtamalleolar and inframalleolar peroneus longus tendon, with a complex tear measuring 5.0 cm in length. Tear extends from the juxtamalleolar segment into the inframalleolar segment, to just proximal to the small os peroneus. Peroneus longus hypertrophic tendinosis without tearing through the cuboid tunnel and distal plantar aspect. Peroneal retinaculum swollen but intact. Peroneus brevis unremarkable.

Extensor tendons intact and unremarkable in appearance. Flexor tendons intact and unremarkable.

Achilles tendon intact. Small enthesophyte without active osteoedema/inflammation at the distal Achilles insertion/dorsal calcaneus.

GENERAL:

Sinus tarsi: Unremarkable.

Muscles: No traumatic muscle injury. No volumetric muscle atrophy.

Soft tissue: Unremarkable.

Plantar fascia: Intact.

Neurovascular complex/tarsal tunnel: Unremarkable. No evidence of entrapment neuropathy.

Intra-articular/loose bodies: None.

Impressions

  1. Diffuse moderate to marked hypertrophic tendinosis/tenosynovitis involving the supramalleolar, juxtamalleolar and inframalleolar peroneus longus tendon with an associated complex (predominantly longitudinal interstitial) tear measuring 5 cm in length.
  2. Giant hypertrophic elongated lateral calcaneal peroneal tubercle (likely predisposing to the adjacent peroneus longus tendinopathy/tearing). Reactive osteoedema.
  3. Incidental small juxta-cuboid os peroneus. Plantar and juxta-cuboid peroneus longus tendinosis. No tendon tearing around the ossicle. 
  4. Incidental 2nd and 3rd tarsometatarsal arthrosis as described.