Plantar Fasciitis and Fibromatosis

KEY FACTS

• Plantar fascia = multilayered fibrous aponeurosis, 1-2 mm thick, with medial, central, and lateral bands

• Likelihood of plantar fasciitis increases with increasing thickness of plantar fascia at calcaneal insertion

Heel fat pat atrophy is most common differential diagnosis
• Plantar fibromatosis = distinct plantar fascial nodule separate from calcaneal insertion

Plantar fascial tear is most similar differential diagnosis

• Plantar fasciitis: Jogger’s heel, tennis heel, policeman’s heel, heel spur syndrome, calcaneal spur syndrome, plantar fasciopathy
• Plantar fibromatosis: Ledderhose disease, plantar fibroma

• Plantar fascia = multilayered fibrous aponeurosis, 1-2 mm thick, with medial, central, and lateral bands

Supports long and short plantar ligaments in maintaining longitudinal arches of foot

– Innervated by medial calcaneal nerve and 1st branch lateral plantar nerve

Entrapment of 1st branch lateral plantar nerve (Baxter neuropathy) can simulate plantar fasciitis

Medial band is least significant

– Inserts into 1st metatarsophalangeal joint

Central band is largest; originates from medial tuberosity of calcaneum

– Divides in forefoot into 5 bands that insert onto plantar plates of metatarsophalangeal joints

Lateral band inserts into base of 5th metatarsal bone
• Plantar fasciitis: Degeneration ± fibroblastic proliferation of plantar fascia insertion to medial tuberosity of calcaneus

As there is no clear inflammatory component, plantar fasciopathy may be more favorable term
• Plantar fibromatosis: Nodular fibroblastic proliferation of plantar fascia separate from calcaneus

• Best diagnostic clue

Plantar fasciitis: Thickened plantar fascial insertion

Plantar fibromatosis: Nodular thickening of plantar fascia
• Location

Plantar fasciitis: Medial tuberosity calcaneus

– Bilateral in 1/3

Plantar fibromatosis: Affects medial (60%) or central bands (40%) of plantar fascia

– Bilateral in 1/3

– Multiple on symptomatic side in 1/4
• Size

Plantar fasciitis: Fascial thickness > 4.5 mm

Plantar fibromatosis

– Average length: 13 mm (range: 4-17 mm)

– Average width: 10 mm (range: 4-22 mm)

– Average depth: 4 mm (range: 2-10 mm)
• Morphology

Plantar fasciitis: Fascial thickening at calcaneal insertion

Plantar fibromatosis: Discrete well-defined plantar fascia nodule

• T1WI

Plantar fasciitis: Hypo – or isointense plantar fascial thickening at calcaneal insertion

Plantar fibromatosis: Isointense plantar fascial nodule
• T2WI

Plantar fibromatosis: Hypo- to isointense nodule along plantar fascia
• STIR

Plantar fasciitis

– Thickness > 4.5 mm (almost 100%)

– Subcutaneous or perifascial edema (90%)

– Insertional bone marrow edema (40%)

– Markedly insertional marrow edema, erosions, and hyperostosis suggest enthesitis (peripheral spondyloarthropathy)

Apr 9, 2020 | Posted by admin in MUSCULOSKELETAL IMAGING | Comments Off