A hammer toe or contracted toe is a deformity of the muscles and ligaments of the proximal interphalangeal joint of the second, third, fourth, or fifth toe causing it to be bent, resembling a hammer. In the early stage a flexible hammertoe is movable at the joints; a rigid hammertoe joint cannot be moved and usually requires surgery.Mallet toe is a similar condition affecting the distal interphalangeal joint.Claw toe is another similar condition, with dorsiflexion of the proximal phalanx on the lesser metatarsophalangeal joint, combined with flexion of both the proximal and distal interphalangeal joints. Claw toe can affect the second, third, fourth, or fifth toes. Risk factors
Older people are more likely to develop hammer toes. Women are at higher risk, due to the construction of womens shoes. Injuries to the toes, and being born with a big toe that is short in comparison to the second toe, increase risk. Arthritis and diabetes may also increase the risk of foot deformities. Causes
Hammertoes and clawtoes have multiple causes. Hammer toe most frequently results from wearing poorly fitting shoes that can force the toe into a bent position, such as high heels or shoes that are too short or narrow for the foot. Having the toes bent for long periods of time can cause the muscles in them to shorten, resulting in the hammer toe deformity.
Among similar antiparkinsonian drugs, cabergoline exhibits the same type of serotonin receptor binding as pergolide. Although lisuride, a related drug, also binds to the 5-HT2B receptor, it acts as an antagonist rather than as an agonist.In January 2007, cabergoline (Dostinex) was reported also to be associated with valvular proliferation heart damage. Recreational drugs
Several serotonergic recreational drugs, including the empathogens MDA and MDMA ("ecstasy"), and some hallucinogens such as DOI and Bromo-DragonFLY, have all been shown to act as 5-HT2B agonists in vitro, but how significant this may be as a risk factor associated with their recreational use is unclear. The piperazine derivative mCPP (a major metabolite of trazodone) is a 5-HT2B agonist in animal models, but actually behaves as a 5-HT2B antagonist in humans. MDMA
One study of human users of MDMA ("ecstasy") found that they did have heart valve changes suggestive of early cardiac fibrosis, which were not present in non-MDMA using controls, suggesting that MDMA use certainly has the potential to cause this kind of heart damage.On the other hand, there is as yet no statistical evidence to establish or negate significant increases in rates of cardiac valvopathies in current or former MDMA users. Absent studies on point, it may be speculated that as with other 5-HT2B agonists, development of heart valve damage may be dependent on the frequency and duration of use and the total cumulative exposure over time. If that is the case, then the heaviest users are likely to face the greatest risk of heart damage.