Metatarsalgia
Metatarsalgia is characterized by pain in the forefoot. The term literally means pain on the metatarsal (there are 5 metatarsal bones in the forefoot). Metatarsalgia is not a true diagnosis but rather it is a symptom. Patients with metatarsalgia present with pain in their forefoot, usually in the “ball” of the foot. The pain is often described as aching and it is typically aggravated by standing and walking. In general metatarsalgia is caused by repetitive overloading of the forefoot leading to chronic localized tissue injury. Often the most symptomatic area is at the base of the 2nd or 3rd toe. Factors that may predispose to the development of metatarsalgia include: a bunion deformity, arthritis of the great toe, ligament instability of the midfoot, an excessively tight calf muscle, a congenital foot deformity, and claw toe deformities.
Non-operative treatment of metatarsalgia is often successful. Treatment principles include:
- Making the correct diagnosis and addressing the underlying cause of the symptom.
- Diminishing the repetitive loading through the forefoot
- Dispersing the loading on the forefoot over a wider area.
The pain that is experienced in metatarsalagia typically occurs in the forefoot at the base of the second or third toes (under the second or third metatarsal head). It often feels like walking “on stones” or “a rolled up sock” at the base of the involved toes. The pain is often described as aching and it is aggravated by standing and walking, particularly on hard surfaces. There may also be a burning sensation extending into the tips of the toes.
As the condition progresses it may be associated with increased clawing of the toes . This can cause the fatty tissue that provides shock absorption to the forefoot to no longer be located under the weight-bearing bones of the forefoot (distal migration of the plantar fat pad leaving the MTP joints “uncovered”). This results in less protection for the metatarsal heads; less shock absorption as they bear weight, and worsening of the symptoms. Unfortunately for some patients, the cause of metatarsalagia is hidden by the secondary deformity that develops and worsens the symptoms. If a Harris mat (a device that assesses how force is distributed throughout the foot) is performed, there is often an intense uptake over the involved metatarsal head. Continued localized, repetitive loading to the involved area will predipose to chronic injury to the structures being loaded. These structures that are commonly injured include the digital nerve (Morton’s nerve), the MTP joint capsule, the plantar plate, and the metatarsal bone (head and/or neck).
Note: Many patients and physicians misdiagnose a Morton’s neuroma for other forms of metatarsagia. While Morton’s neuroma is a cause of metatarsalgia, neuritis (nerve inflammation) secondary to the chronic repetitive joint injury is far more common. In this situation removing the Morton’s nerve may lead to incomplete and temporary pain relief.
Imaging Studies
Radiographs may demonstrate a relatively long second or third metatarsal relative to the first and the fourth. In rare instances, the MTP joint may actually be subluxed (partially out of joint) or even dislocated. Deformities of the 1st Metatarsal such as those present with a Bunion or with Midfoot instability may also be observed on x-ray.
Treatment
Non-Operative Treatment
Patients respond well to non-operative treatment. If the underlying cause can be addressed non-operative treatment will be successful in the long-term. The principle of non-operative treatment is to off load the involved area. This can be done with a combination of comfort shoes, metatarsal pads, soft accommodative orthotics, activity modifications, calf stretching, and foot muscle strengthening and NSAIDS (Non-steroidal anti-inflammatory drugs).
- Comfort shoes
- Metatarsal pads
- Soft Orthotics
- Hammertoe crest pad
- Activity modification
- Anti-inflammatory medications (NSAIDs)
- Corticosteroid Injections
Operative Treatment
In a small percentage of patients, non-operative treatment will fail. In these patients, surgery may be helpful. There are a variety of procedures that have been proposed either in isolation or in combination.
