Question about hand muscle wasting with clawing...

Hey folks,

I recently assessed a patient with a sprained wrist (2 weeks post injury). He also has pre-existing clawing of his ring and pinky fingers as well as MARKED wasting of the muscles in his dorsal webspace (between thumb and index). Cervical scan was negative (C8 and T1 myotomes were not accurately tested due to the hand muscle wasting). What could cause this hand deformity? Wouldn't it be both radial and ulnar nerve compression? Wouldn't there also be sensation changes if it was nerve compression?

Thanks in advance.

Willeseden

Willeseden;

Check for Dupuytren's contracture as a cause of clawing of D4 & D5; this may be unrelated to the muscle wasting.

If the thenar muscles are not atrophied & weak, then it is unlikely a problem at the neck (e.g., a C8 or T1 root lesion). Is the flexor carpi ulnaris weak? How about the flexor digitorum profundus to D4 & D5? If they are both ok, and the weakness is limited to the hand alone, then suspect an ulnar nerve injury at the wrist. If these are also weak, then suspect an ulnar nerve injury at the elbow.

Is the other hand ok? If there is any atrophy in the other hand, look at the tongue; check for weakness and fasciculations. If these are ok, then it is not likely ALS.

Is sensation really intact in the ulnar nerve distribution? I've had several patients with severe ulnar nerve compression, but preserved 2-point discrimination and light touch. I can't really explain it, but sometimes the motor fibers are much more involved than sensory.

Other than checking these issues, an EMG & NCV would really help clarify.

Thanks for your reply. The other hand was fine. There was no Dupuytren's contracture on the affected hand. FCU was strong but painful as the patient has a wrist sprain. Pinky abduction was markedly weak. I didn't explicity test FDP of D4 and D5, but grip strength was 50kg on the unaffected hand and 22kg on the affected hand. I may never see this patient again- he was a worker's compensation patient and I sent him back to the insurance company for an independent assesment. This was definitely something I had never seen before.

Willeseden

I don't wish to sound cynical but perhaps an EMG study would be the best first option of investigation. If there is true muscle weakness then it will show up on that and a clear way forward might present. The suggestion might be an interesting option in terms of guaging the reaction in any compensation patient. 8o

I suggest researching "Hirayama's Disease". Very rare condition affecting anterior horn cells of spinal cord around C7 leading to weakness and wasting of hand with absence of pain or sensory loss. Typically seen in young males, although progressive, it is considered benign, stabilising after a few years. Cause essentially unknown, treatment experimental ranging from nothing, to extended use of hard collar to cervical fusion. Japanese researchers have also been doing studies with plasma exchange, though results have only been transient unless done in conjuction with immobilisation in a hard collar.My son was diagnosed last year and had C6/7 fusion which halted the progression and restored some strength and function.

Rosemary (Sydney 02 9521 4688 )

can we think hansen's disease and an involvement of high ulnar and low median nerve prior to wrist sprain
NCV would give us a good picture
regards
sandeep

Hi,

My suggestion is that advive the patient to go for a nerve conduction test before coming to a conclusion. There is a chance of entrapment of Median N . As you said there was a wrist sprain , what was the outcome of that , is there a malunion .