FDM brevis of the foot forms the lateral plantar compartment with the abductor digiti minimi. Its origin at the fifth metatarsal base is adjacent to the insertion of peroneus brevis — an important relationship in fifth metatarsal fracture surgery.
| Origin | Base of the fifth metatarsal — plantar surface; Fibular (peroneus) longus tendon sheath |
|---|---|
| Insertion | Lateral base of the fifth toe proximal phalanx |
| Nerve Supply | Superficial branch of the lateral plantar nerve (S2, S3) |
| Blood Supply | Lateral plantar artery |
| Actions | Flexes the fifth toe MTP joint; Assists in weight bearing on the lateral forefoot |
|---|
In fifth metatarsal base fractures (avulsion — Zone 1), the FDM origin is not typically involved (the fracture is from peroneus brevis pull). However, in Zone 2 (Jones fracture), the FDM origin lies proximal to the fracture and is preserved. FDM is identified during lateral fifth toe arthroplasty.
Palpated on the lateral plantar foot during resisted little toe MTP flexion.
The FDM origin at the fifth metatarsal base proximal to the Jones fracture zone, preserved in Zone 2 fracture surgery.
