9th Aug 2021

ICRI CASE OF WEEK

Contributed by- Dr Chaitali Parekh

Consultant Musculoskeletal Interventional Radiologist
Pulse chain of centres, Mumbai
Nutech diagnostic centre, Kalyan

Copyright : Dr Chaitali Parekh

DNB, FRCR(UK)
Fellowship in Musculoskeletal Interventional Radiology

Case History

• 64 year old female presented with long standing left
ankle pain, increased on weight bearing, and more so
on lateral aspect of the ankle.

• No history of trauma.

• No clinical signs of infection.

STANDING

What are the Findings?

ab

What is the angle depicted and what does it imply?

c

What soft tissue structure is missing at the site of the arrow?

de f

What are the Findings?

g

What are the Findings?

EXPLANATION

STANDING

Lateral weight bearing radiograph of the foot - shows pes planus.
Increased Meary angle / talo-first metatarsal angle.
No acute fracture or destructive osseous lesion.
Small os trigonum.

ab
PD coronal (a, b) images - The angle is talocalcaneal angle which is
measured between the medial wall of calcaneum and long axis of tibia.
On MRI, it is measured on the coronal image. Normal angle = 6o.
The angle is increased in this patient implying heel valgus

navicular

c
PD axial image (c) - The arrow shows an absent/ full thickness tear of the
tibialis posterior tendon at the navicular attachment with fluid in the tendon
sheath. Flexor digitorum longus and flexor hallucis longus are well visualized.

de f

T2fs (d) and PD (e) sagittal images of the ankle show moderate intraosseous cystic
changes and marrow edema in the lateral talar process and adjoining angle of Gissane
of the calcaneum. Mild posterior tibial chondral thinning. Preserved subtalar articular
cartilage. This is suggestive of extra-articular lateral talocalcaneal impingement.
T2fs axial (f) image shows moderate tibiotalar joint effusion with synovial thickening.

g

PD coronal (g) image shows moderate degeneration of calcaneofibular ligament
(arrow) with mild to moderate inframalleolar peroneus longus degeneration/
tendinosis (arrow head), interposed between the lateral malleolus and calcaneum.
This is suggestive of subfibular impingement.

What is the Final Diagnosis?

Pes planus with heel valgus and tibialis
posterior tendon dysfunction (full thickness
tibialis posterior tendon tear)

Lateral hindfoot impingement syndrome
(extra-articular talocalcaneal and subfibular
impingement)

Discussion

• Patients with pes planus and heel valgus may
develop lateral ankle pain attributed to lateral
hindfoot impingement.

• It is believed to be secondary to talocalcaneal joint
subluxation due to heel valgus and resultant lateral
shift of the weight bearing forces from talar dome to
lateral talus and fibula.

Pes planus with heel valgus (due to multiple causes)

Talocalcaneal joint subluxation

Increasing heel valgus

Impaction of lateral talus and calcaneum – talocalcaneal impingement

Further increasing heel valgus

Lateral soft tissue impingement (calcaneofibular ligament and peroneal tendons)
between fibula and lateral calcaneum – subfibular impingement

Normal space between the lateral talar On the left image with heel valgus the lateral
process (asterix), angle of Gissane (arrow tlaus impacts against lateral calcaneum. With
head) and lateral malleolus (arrow) more severe heel valgus (right image), the
lateral calcaneum impacts against lateral
https://radsource.us/lateral-hindfoot-impingement/ malleolus.

• Lateral hindfoot impingement can occur secondary
to tibialis posterior tendon dysfunction, healed intra-
articular fractures, neuropathic arthropathy and
inflammatory arthropathy.

• With progressive deformity, secondary
osteoarthrosis can develop in subtalar, talonavicular
and calcaneocuboid articulations.

Teaching Points

• Tibialis posterior dysfunction with pes planus and
heel valgus can result into lateral hindfoot
impingement causing lateral ankle pain

• Talocalcaneal impingement typically occurs before
subfibular impingement.