Numbness in leg during competitive racing

[lincur]

Hi

My daughter is 26 years old and is a competitive athlete and has been since she was 11 years of age.  She trains six times a week and competes usually twice a month in high quality races with no problems and is achieving good times.  However on the last three occasions when she was racing she has developed a numbness in her right thigh from the knee upwards in which she says she cannot feel her leg and it is as though it is "dead".  It is so bad that she has to limp and can hardly finish the race.  After the race there is no pain what soever in the leg and it never happens during training.  She sees her physio regularly and has regular massages.  He has no idea what is causing the pain and cant find any injury on examination.  She did have a skiing accident resulting in an arthroscopy four years ago which has not affected her running at all.  Do you have any idea on what it is or what she should next as she is unable to compete until this problem is sorted out.  Thanks very much for any advice.

[lincur]

Thanks very  much for this information.  Do you happen to know if the first one of thes is treatable.

Also if the the second one is the case would this be treatable.

Is the next port of call a referral to an orthopaedic surgeon at the local hospital or someone more specialised.

Thanks

[Michael L Gross, MD]

First, I don't think this is at all related to her skiing accident 4 years ago.  Three possibilities come to mind.  
First, is realted to nerve impingent in the lower back. Either from a disc herniation or spinal stenosis.  This could cause irritation of the L4 or L5 nerve root causing pain and numbness down the front of the thigh.  This can be diagnosed by MRI.
Second,is an exertional compartment sydrome.  Although more common in the lower leg, it can occur in the thigh. When the muscle compartments are tight, increased blood flow during exertion causes swelling in the muscles against the tense, tight fascia.  As the muscle becomes more swollen, the fascia becomes tighter and eventually cuts off the circulation.  This, in turn, initially causes pain, then numbness, and eventually muscle death.  Exertional compartment syndrome is diagnosed by measuring compartment pressures before and after exercise.
Finally, and least likely, there could be some other problem with the circulation. either arterial spasm or even a clot.  Vascular studies should rule this out.