Acrocyanosis is blueness of the extremities (the hands and feet). Acrocyanosis is typically symmetrical. It is marked by a mottled blue or red discoloration of the skin on the fingers and wrists and the toes and ankles. Profuse sweating and coldness of the fingers and toes may also occur.
Acrocyanosis is caused by narrowing (constriction) of small arterioles (tiny arteries) toward the end of the arms and legs.
Athletes who take part in high-impact sports involving running or jumping are at high risk of forefoot injury. While track and field runners are exposed to the highest level of traumatic forces to the forefoot, many other athletes, including tennis, football, baseball, and soccer players, often have forefoot injuries.
SYMPTOMS AND CAUSES
The primary symptom of metatarsalgia is pain at the end of one or more of the metatarsal bones. The pain is typically aggravated when walking or running. Athletes who participate in high-impact activities and may also have an inflammatory condition such as bursitis often have diffuse forefoot and midfoot pain.
Most often, the pain comes on over a period of several months, rather than suddenly.
A condition known as Morton's neuroma (interdigital neuroma) produces symptoms of metatarsalgia due to irritation and inflammation of a nerve at the site of pain. People with Morton's neuroma may experience toe numbness in addition to pain in the forefoot.
The foot can be injured during sports activities. As with many other overuse injuries, the condition may be the result of an alteration in normal biomechanics that has caused an abnormal weight distribution.
Persistent stress can lead to chronic irritation and inflammation of the bone covering and adjacent tissues, such as ligaments and tendons.
The following factors can contribute to excessive localized pressure over the forefoot:
Excessive pronation (side-to-side movement of the foot when walking or running)
Some anatomical conditions may predispose individuals to forefoot problems. They include:
A high arch
A short first metatarsal bone often seen in people with a Morton toe; the normal forefoot balance is disturbed, resulting in the shift of an increased amount of weight to the second metatarsal.
Any or all of the above musculoskeletal problems may contribute to forefoot trauma in athletes.
X-rays may be helpful in excluding other causes of forefoot pain.
A bone scan can pinpoint places of inflammation.
Ultrasound can help identify conditions such as bursitis or Morton neuroma that can be causing pain in the metatarsal region of the foot.
The doctor may also ask for an MRI to help detect and diagnose many causes of pain in the metatarsal and midfoot regions. These can include traumatic disorders, circulatory conditions, arthritis, neuroarthropathies, and conditions that result in biomechanical imbalance.
The doctor may also ask for other tests and procedures to help in the diagnosis and in determining the proper treatment.