[23,24] It has been shown that motor fibers innervating the thenar muscles
are relatively protected, compared to motor branches of the lumbrical muscles.
Limbs examination showed atrophy of left thenar muscles
There are wide discrepancies regarding prevalence of CRA and the thenar muscles
innervation based on different methods of investigation that have produced increased results, such a eletromyography studies, anatomical studies, nerve block, and clinical examinations were used.
With more complex deformities, a varying decrease in thenar muscle
mass and first webspace contracture can be appreciated.
Hudson and Dejager reported the results of 76 flex-or tendon repair in 15 patients and found 36 excellent, 5 good, and 20 fair and 15 poor results in the patients.13 Kabak et al in their series of 21 patients with simultaneous median or ulnar nerve lacerations with flexor tendons cuts, found 76% good to excellent results and better outcome for median nerve than ulnar nerve repair.14 In our study return of thenar muscle
function was better than intrinsic ulnar muscles innervated.
Other evolutionary changes occurred to accommodate this new mobility of the thumb, including development of thenar muscles
for opposition and the extensor pollicis brevis tendon for extension.
On examination, he had wasting of right thenar muscles
Physical examination showed that he had thenar muscles
and distal lower limbs atrophy, foot dorsiflexion weakness (scored 1/5 on Medical Research Council [MRC]), reduced vibration sense, absent tendon reflexes, pes cavus, and strephenopodia.
The modified Blauth classification is commonly used to classify the condition, which is based on the atrophy of the thenar muscles
, the contracture of the adductor pollicis, and the degree of dysplasia of the metacarpus in the thumb .
Loss of control of the thenar muscles
situated in the palm of the hand between thumb and index finger is generally one of the first signs of ALS.
It supplies most forearm flexors and thenar muscles
and provides sensory innervations to the lateral aspect of palm and dorsal surfaces of terminal phalanges along with the palmer surface of thumb, index, middle, and half of ring fingers.
For example, cortical motor-evoked potential facilitation has been reported following short duration (5 s), submaximal intensity contractions (50%) of the thenar muscles
(Balbi et al., 2002).
C reflex was recorded with superficial electrodes placed on the thenar muscles
. Recordings were made simultaneously with four channels: C3' - Fz, Cz' - Fz, C4' - Fz, and the thenar muscles
Fatigue of paralyzed and control thenar muscles
induced by variable or constant frequency stimulation.
In more advanced cases, atrophy of the thenar muscles
can occur (4).