In an earlier blog (http://tinyurl.com/285eurj  ), I discussed the common lateral foot and ankle pain syndromes in the foot. I recently stumbled on a great case, which is applicable to that theme.
Stress fractures are common in the foot and they most often affect the metatarsal bones. The distal second metatarsal neck is the most common site of a stress fracture in the foot. Stress fractures of the third or fourth metatarsals are less frequent. I think we can all agree that stress fractures of the first and fifth metatarsal bones are relatively rare.
I had a 67-year-old woman patient see me recently with pain on both feet with the right foot worse than the left. She complained of pain for about a year on and off. She had previous treatment by another podiatrist who told her that she had bone spurs on the top of her feet. She had one cortisone injection but it did not help much.
Her examination was remarkable for pain with palpation of the dorsal bony prominence of the tarsometatarsal joints. There was also generalized tenderness over the base of the fourth and fifth metatarsal bases. Bilateral X-rays revealed an old stress fracture of the left second metatarsal. Mild to moderate degenerative joint disease of the tarsometatarsal joints was present. There was an underlying metatarsus adductus.
At the patient’s first office visit, my working diagnosis was osteoarthritis of the tarsometatarsal joints with exostosis and lateral stress syndrome of the foot secondary to metatarsus adductus. I call this condition metatarsal periostitis. Her treatment included shoe gear modification to avoid flimsy shoes, which increase stress to the foot. I recommended a stiff soled athletic shoe and alternating her lacing pattern to avoid pressure to the dorsal exostosis. I prescribed diclofenac 75 mg BID PC #60. She initiated an icing protocol TID x 15 minutes. I instructed her to follow up in three weeks.
On her return visit, she was not getting better and, in fact, stated that she was worse. She tried wearing better shoes and she even went to an orthotist to have a pair of orthotics made but these did not help either. Upon re-examination of the patient, it seemed as if the pain was more on the lateral side of the right foot.
At this point, I dispensed a fracture boot to immobilize the foot and advised her to wear it during all weightbearing activities. I gave her a prescription for diclofenac patches (the oral medication caused gastrointestinal upset) and hydrocodone (Vicodin, Abbott Laboratories). She was to follow up in two weeks.
On her following visit, she was approximately 80 percent better. Repeat X-rays revealed a stress fracture of the fifth metatarsal, which was now quite obvious.
What I find very interesting about this case is that I have always believed in the theory that a Jones fracture was a "stress fracture in the making." Since most Jones fractures that we see in practice are a result of an injury (foot plantarflexed with an inversion torque), it is hard to prove the stress fracture theory. I think this is a perfect case in point to illustrate this.
This patient also has a metatarsus adductus. You will see lateral foot and ankle pathology over and over again in the pes cavus and/or metatarsus adductus foot type.