WHAT IS IT?
Metatarsalgia means literally pain(=algia) under the metatarsal bone(s) which are located under the forefoot.It has many causes and a specific clinical examination usually determines its aetiology and a targeted treatment can then be proposed.
The body’s weight is distributed between the five metatarsals (bones in the midfoot, linking with the toes). The first bone, linked to the big toe, receives 2.5 times more weight than the others. The rest of the weight is then divided among the other metatarsals. Any imbalance of this relationship causes a cascading change meaning that an extra burden falls onto one or more of the other metatarsals. Pain then develops specifically under the overburdened metatarsals.
Other pathologies can hide themselves under the so called metatarsalgia : a stress fracture of the metatarsal or phalanx, a rupture of the stabilizing plantar structure of the metatarsophalangeal joints, a dislocation of the toe, the formation of hammer toes,…
Multiple causes may underlie this problem. The overpressure may be due to a shortened Achilles tendon, a metatarsal which is anatomically too long or to steep (on side view) compared to the other, an age-related sagging of the forefoot, often in combination with hallux valgus, in certain high arched feet, in certain neurological disorders,…
The pain is always located under the metatarsal heads, and protrusions can be easily palpated at the base of the toes with or without callus formation (hard skin). Callus formation is often a relevant clinical sign and can be present very locally, e.g. under the second metatarsal head, or more widespread over the entire forefoot. As long as the hyper pressure under the metatarsal head is not handled, the callus will redevelop itself.
Metatarsalgia is a stress-related pain due to hyper pressure at that specific place.
Traditionally, the second metatarsal is the first affected. Pain is experienced mostly crescendo over daytime when walking and when standing for prolonged periods; the pain improves with rest and increase when wearing high heels.
WHEN SHOULD YOU CONSULT A SPECIALIST?
If the pain persists despite restricting the excess burden or if the pain becomes incapacitating it’s advisable to consult a specialist. A comprehensive and specific clinical examination will help make an accurate diagnosis and offer the appropriate treatment.
The examination is generally completed by a radiological evaluation, to refine the diagnosis and determine the cause of the condition.
The treatment is primarily non-surgical. The pressure on the forefoot can be reduced by relaxing the muscles of the calf by performing stretching exercises of the gastrocnemius muscle (Achilles tendon). Custom-made orthopaedic or podiatric insoles might as well redistribute the pressure under various metatarsal heads. Sometimes, in very specific cases, an infiltration, followed by 6 weeks of taping, can bring some comfort
If these treatments are not sufficient, surgery may be considered. In any case, the entire foot function has to be taken into consideration. This treatment can be performed alone or combined with other surgical procedures :
- Lengthening of the gastrocnemius muscle at the proximal part of the leg;
- Transfer of a flexor tendon;
- Suture of the stabilizing plantar plate;
- In case of hallux valgus or varus deformity of the big toe, this pathology should also be surgically corrected.
- The most common procedure is an osteotomy (open or percutaneous) in which the pressure of the metatarsal bone(s), responsible for the overpressure, is relieved by shortening it a few millimetres, or by slightly lifting it up, or by a combination. After such an osteotomy, a screw is usually placed, to make sure that the predetermined shortening is maintained. After the operation, one may in fact immediately bear weight on a specifically designed postoperative shoe.
More recently, percutaneous surgery has changed these bone sections (osteotomy) through an absence of fixations, systematic treatment of the three central digits and a different theoretical approach. In fact, the released heads move when walking, until they reach a balance corresponding to a uniform distribution of loads. It is therefore the body’s own biomechanics and not the surgery that will determine the optimal position of the metatarsal heads. This technique is called DMMO (Distal Minimally invasive Metatarsal Osteotomy).
POST SURGICAL FOLLOW UP
After any procedure on the metatarsal bones (classic Weil osteotomy or percutaneous surgery), a special orthopaedic shoe is usually required for 6 weeks. The foot may remain swollen and sensitive for 1-3 months. Discomfort decreases rapidly once the bone is completely healed; x-ray confirmation is required during follow-up consultations.
Less energetic sports such as swimming or riding a bike can start 6 weeks after surgery; running or contact sports can resume after 3 months.
Driving can resume after 6 weeks. When only one foot has been operated on, driving is allowed after a shorter time, on condition the car is an automatic one.
A period of around 2 to 9 weeks off work is generally required, depending on the type of job.
RISKS AND COMPLICATIONS
Besides the possible complications after any type of surgery (thrombosis, infection <1%, algodystrophy <1%), the following complications may occur after a metatarsal osteotomy:
- Delayed or absence of bone consolidation (very rare)
- Persistent swelling of the foot lasting for longer than 12 weeks (common) usually spontaneously regressive
- Persistent pain (rare)
- The possible risks or complications during other procedures are specific to the type of surgery and your specialist will provide full information to you.
- Joint stiffness. This is a frequent occurrence and must be limited by early postop daily exercises, starting a few weeks after surgery.