Gentleman came in, several month history of left forefoot pain and plantar foot cramping after long walks and long bikes or sessions on the indoor bike trainer. Typically clipped in. Notable, left calf atrophy (see pic) from a 30 year old achilles repair. Terminal Heel rise is impaired and weak and challenged calf endurance. Left calf is also short, obviously.
Exam found notable over recruitment of the long toe flexors (also off that posterior compartment) -- afterall, someone in that posterior compartment has to be creating propulsion and heel rise (even that is a long shot of a strategy for the long toe flexors).
Long toe flexor overactivity causes toe hammering, inhibition of the short toe flexors, distal migration of the metatarsal fat pad and inhibition of the lumbricals.
Translation: overburden of the forefoot in loading, both from fat pad migration, lumbrical inhibition and premature heel rise (from short calf-achilles and atrophy, and altered heel rise strategy as noted above).
The metatarsals are small bones -- they don't mind loading but it has to be clean appropriate loading to repetitively endure it without problem. Forefoot loading can be a challenge when the mechanics are off. The lumbricals are part of this scenario -- if they are weak or inhibited proper posturing of the forefoot during forefoot loading is compromised and the ability to stabilize the toe is flawed (this is a common problem in hammer toes (functional or anatomical)).
One has to get to the root of the problem on this one . . . . the old achilles trauma and weak calf. Its been 30 years. Time to dig in on this one, start with the basics, and look at a long calendar for change.
Just some quick thoughts on this case that walked in today. Forefoot pain -- it can be complicated.
Oh, and guess what else was off ? Yup, hip extension and gluteal-hip stability. Duh.
- Dr. Shawn Allen, the other gait guy