Pes Cavus - Arched/High Foot

In part of my reading around I realised that I've spotted many references to "Pes Cavus" in HSP articles, and I didnt know what it was, so time for a quick trawl.

Pes Cavus has a range of other names: high instep, high arch, talipes cavus, cavoid foot, and supinated foot.  It's translation from latin is hollow foot.

Normally, when you stand up your foot flattens. If you've got pes cavus then it doesn't (or at least doesn't as much). This is the opposite of flat feet, and in the general population  pes cavus is much less common than flat feet. Diagram: http://docpods.com/high-arched-feet-pes-cavus-inverted-foot-types

Unlike flat feet, highly arched feet tend to be painful because more stress is placed on the section of the foot between the ankle and toes (metatarsals). This condition can make it difficult to fit into shoes. 

The high arch shape is either due to a tight or contracted plantar fascia (the tough sheet of fibrous tissue that runs along the sole of the foot) or due to a weakness in one muscle group causing unopposed action of the other, resulting in fixed plantar flexion of the foot (think pressing your foot on the accelerator or standing on tip-toes). I suspect that for HSP-ers it's the former of these. 

The symptoms are:

• Shortened foot length
• Difficulty fitting shoes
• Foot pain with walking, standing, and running (not everyone has this symptom)

The majority of this info came from here:
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002241/

There's a picture of someones feet laying in bed in a Google image search where their feet are pointing more along the bed rather than up in the air. I'm finding that my feet are tending to go in the same direction, so perhaps I'm heading for pes cavus myself.

Using my papers search I find from 1981:

Heel deformity in hereditary spastic paraplegia, by Rothschild H, Shoji H, McCormick D, in Clin Orthop Relat Res. 1981 Oct;(160):48-51. http://www.ncbi.nlm.nih.gov/pubmed/?term=7285436 


Varus deformity of the heel is often associated with, and may even precede the development of pes cavus. Clinical and radiographic examinations of the feet of members of three kindreds of hereditary spastic paraplegia, suggested that the autosomal dominant form manifests a significantly higher incidence and degree of heel varus deformity than the autosomal recessive  form of the disease. 



Various other web sites were mentioning pes cavus in realtion to Charcot-Marie-Tooth (CMT) and to Friedreich's ataxia, which come up in many of the HSP papers I've found.

Of course, I now have to look up Varus deformity as well, and I saw in passing several mentions of "hammer toe".....

...My-my-my-my music hits me so hard....