Metatarsophalangeal joint pain

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Metatarsophalangeal joint pain usually results from tissue changes due to aberrant foot biomechanics. Symptoms and signs include pain with walking and tenderness. Diagnosis is clinical; however, infection or systemic rheumatic diseases (eg, rheumatoid arthritis, psoriatic arthritis) may need to be excluded by testing. Treatment includes orthotics, sometimes local injection, and occasionally surgery.
(See also Overview of Foot and Ankle Disorders.)
Metatarsophalangeal joint pain is a common cause of metatarsalgia. Metatarsophalangeal joint pain most commonly results from misalignment of the joint surfaces with altered foot biomechanics, causing joint subluxations, flexor plate tears, capsular impingement, and joint cartilage destruction (osteoarthrosis). Misaligned joints may cause synovial impingement, with minimal if any heat and swelling (osteoarthritic synovitis).
The 2nd metatarsophalangeal joint is most commonly affected. Usually, inadequate 1st ray (1st cuneiform and 1st metatarsal) function results from excessive pronation (the foot rolling inward and the hindfoot turning outward or everted), often leading to capsulitis and hammer toe deformities. Overactivity of the anterior shin muscles in patients with pes cavus (high arch) and ankle equinus (shortened Achilles tendon that restricts ankle dorsiflexion) deformities tends to cause dorsal joint subluxations with retracted (clawed) digits and retrograde, increased submetatarsal head pressure and pain.
Metatarsophalangeal joint subluxations also occur as a result of chronic inflammatory arthropathy, particularly rheumatoid arthritis (RA). Metatarsophalangeal joint pain with weight bearing and a sense of stiffness in the morning can be significant early signs of early RA. Inflammatory synovitis and interosseous muscle atrophy in RA lead to subluxations of the lesser metatarsophalangeal joints as well, resulting in hammer toe deformities. Consequently, the metatarsal fat pad, which usually cushions the stress between the metatarsals and interdigital nerves during walking, moves distally under the toes; interdigital neuralgia or Morton neuroma may result. To compensate for the loss of cushioning, adventitial calluses and bursae may develop. Coexisting rheumatoid nodules beneath or near the plantarflexed metatarsal heads may increase pain.
Metatarsophalangeal joint pain may also result from functional hallux limitus, which limits passive and active joint motion at the 1st metatarsophalangeal joint. Patients usually have foot pronation disorders that result in elevation of the 1st ray with lowering of the medial longitudinal arch during weight bearing. As a result of the 1st ray elevation, the proximal phalanx of the great toe cannot freely extend on the 1st metatarsal head; the result is jamming at the dorsal joint leading to osteoarthritic changes and loss of joint motion. Over time, pain may develop. Another cause of 1st metatarsophalangeal joint pain due to limited motion is direct trauma with stenosis of the flexor hallucis brevis, usually occurring within the tarsal tunnel. If pain is chronic, the joint may become less mobile with an arthrosis (hallux rigidus), which can be debilitating.
Acute arthritis can occur secondary to systemic arthritides such as gout, RA, and spondyloarthropathy.