The foot lumbricals (four in total) act like those of the hand — they flex the MTP joints and extend the IP joints. Their loss from peripheral neuropathy produces the classic intrinsic minus foot with claw toes.
| Origin | Medial sides of the FDL tendons — the first from the FDL tendon to the second toe, the remaining three from adjacent FDL tendons |
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| Insertion | Medial sides of the extensor expansions of the second through fifth toes |
| Nerve Supply | First lumbrical: medial plantar nerve (S2, S3); Lumbricals 2-4: lateral plantar nerve (S2, S3) |
| Blood Supply | Plantar metatarsal arteries |
| Actions | Flex the MTP joints; Extend the PIP and DIP joints — via the extensor expansion (analogous to hand lumbricals); Stabilise the toe during push-off |
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First lumbrical has medial plantar nerve supply while the remaining three have lateral plantar nerve supply — relevant in peripheral nerve block assessment of the plantar foot. In surgical correction of fixed clawtoe, lumbrical transfer to the extensor hood is performed to restore the intrinsic function.
Not individually palpable. Assessed collectively by toe MTP flexion with IP extended.
Transfer of the foot lumbrical to the extensor hood of a clawtoe to restore intrinsic balance — flexing the MTP joint while extending the IP joints.