Sensory ([micro]V) Median Wrist Third finger >20 Ulnar Wrist Fifth finger >18 Sural Calf Wrist >5 Median Wrist APB >5 Elbow APB Ulnar Wrist ADM >7 Below Elbow ADM Peroneal Ankle EDB >3 Below Knee EDB Tibial Ankle AH >6 Knee AH Latency (ms) V (m/s) F wave (ms) Median <3.4 >50 Ulnar <3.0 >50 Sural <4.5 >40 Median <4.1 >50 <31 Ulnar <3.1 >50 <32 Peroneal <5.1 >40 <50 Tibial <5.5 >40 <51 APB: abductor pollicis brevis
; ADM: abductor digiti minimi; EDB: extensor digitorum brevis; AH: abductor hallucis; V: velocity Table 2.
In February 2011, an outpatient electrophysiologic evaluation showed a severe right focal demyelination of the median nerve at the wrist and mild acute denervation in the abductor pollicis brevis
muscle, consistent with CTS.
For example, in looking at the 3D image of the hand and clicking on a muscle of the thumb, the heading Abductor pollicis brevis
appears to the right along with a description of the muscle, information about its actions, and links to animations and movies showing its movement.
Palpation revealed tenderness and hypertonicity in the muscles of the thenar eminence (Abductor Pollicis Brevis
, Flexor Pollicis Brevis, and Opponens Pollicis).
* Reference electrode- tendon of abductor pollicis brevis
The median nerve also serves the abductor pollicis brevis
, the opponens pollicis, and the superficial head of the flexor pollicis brevis; involves the muscles to the thumb (Li, Harkness, & Goitz, 2005); and is the most specific motor assessment for CTS.
Abductor pollicis brevis
muscle was the pick up for median nerve, stimulated at wrist and elbow.
Effects of the adductor pollicis and abductor pollicis brevis
on thumb metacarpophalangeal joint laxity before and after ulnar collateral ligament reconstruction.
Motor threshold (MT) is the level of stimulation required to produce movement in a contralateral target muscle, such as the abductor pollicis brevis
that causes contraction of the thumb.
A neurological examination demonstrated motor strength changes: 4/5 deltoid and supra and infraspinatus, 3/5 triceps, 1/5 biceps, 2/5 wrist flexion, 0/5 wrist and finger extension, 1/5 lumbricals and interossei, 0/5 abductor pollicis brevis
and 3/5 adductor pollicis on the right.
Six subjects with pacemakers received stimulation of the left peroneal nerve at the left ankle and fibular head with the active surface recording electrode placed over the left extensor digitorum brevis muscle and stimulation of the left median nerve at the wrist and elbow with the active surface recording electrode placed over the left abductor pollicis brevis