This is an interesting case of a triathlete who was ramping up his training for a half-ironman competition and developed a tenderness that was felt on the top of his foot.
He had seen his physician, who made a preliminary diagnosis of a stress fracture, and had sent the patient for a bone scan. The bone scan came back negative for a fracture.
The triathlete came to see me to try and figure out what the problem was. It turns out that the pain he was feeling did not originate in his foot, but was caused by an overload of the muscles in his shin. These muscles developed myofascial trigger points that referred pain to the top of the foot, mimicking a stress fracture.
Myofascial trigger points are defined as “a hyperirritable spot usually within a taut band of skeletal muscle or in the muscle’s fascia, that is painful on compression and that can give rise to characteristic referred pain, tenderness and autonomic phenomena.” (From Travell JG and Simmons DG: “Myofascial Pain and Dysfunction: The Trigger Point Manual”, Williams & Wilkins, Baltimore, 1983, pg.3.)
The trigger points were treated by using acupressure, therapeutic massage, specific manipulation of the foot, and stretching and strengthening exercises. Within two weeks the triathlete resumed training without incident.
Myofascial trigger points (MTPs) are fascinating phenomena that can be misdiagnosed as many other conditions. For example, a MTP in the soleus muscle of the calve, can mimic the symptoms of a heel spur, and MTPs in the pectoral muscles may be mistaken for angina.
The key point here is that pain felt in one area of the body may have its source elsewhere. When I see a patient and cannot directly reproduce their symptoms by orthopedic testing and palpation of the area, I always consider myofascial trigger points as a possibility.
Once myofascial trigger points are identified, they usually respond promptly to conservative care. Seeing at least a 30 percent to 50 percent reduction in symptoms after one treatment is not uncommon. The real challenge is preventing a recurrence which involves resolving any underlying issues such as muscle weakness, imbalances, vitamin deficiencies (especially B-complex), postural stress and vocational stress. One further point is that MTPs do not respond to anti inflammatories or muscle relaxant medication.