The area between the elbow and the wrist
This muscle can be needled by finding the midpoint between the biceps tendon and the medial epicondyle and moving 2 fingerbreadths distally
Pronator teres
Dorsal scapular nerve (3 total)
Levator scapulae, rhomboid major, rhomboid minor
Stim between the Palmaris longus and the FCR tendons (G1 over APB)
Median motor at the wrist
Most common entrapment neuropathy in the body.
Median mononeuropathy at the wrist
Pronator teres
C6-C7
These are the only 2 ulnar-innervated muscles in the forearm
FCU and FDP (serving digits 4 & 5)
Long thoracic nerve
Serratus anterior
Stim at medial wrist, adjacent to the FCU tendon (G1 over ADM)
Ulnar motor (at the wrist)
2nd most common entrapment neuropathy in the upper extremity
Ulnar nerve at the elbow (ulnar groove vs. cubital tunnel)
*Tunnel is 2-3 cm distal. Nerve runs between 2 heads of FCU here.
FCR
C6, C7
After passing between the superficial/deep heads of the pronator teres, the median nerve dives and runs between these 2 muscles.
FDS and FDP
Musculocutaneous
Biceps, brachialis, coracobrachialis
Stim at distal radius (G1 over EPL tendon, G2 over thumb)
Radial sensory
Less than 3% of people are even prone to this very rare cause of proximal median neuropathy
Ligament of Struthers; Ligament present in up to 2.7%; Account for 0.5% cases median neuropathy
FCU
C7, C8
These 3 muscles are innervated by the anterior interosseous nerve, a motor branch of the median nerve.
Flexor pollicis longus, FDP (portion serving D2 &D3), and pronator quadratus
The sensory-only continuation of the musculocutaneous nerve
Lateral forearm (lateral antebrachial cutaneous nerve)
Stim at medial humerus between the biceps and triceps
Ulnar motor (above elbow site)
This is the name given to the proximal, superficial, tendinous layer of the supinator where the radial nerve can be squished
Arcade of Frohse (cause of PIN syndrome)
1st dorsal interosseous muscle
C8, T1
What is the peripheral nerve and nerve root innervation for the mobile wad muscle that flexes the forearm in a semi-pronated position.
Radial; C5-C6 (brachioradialis)
Posterior interosseous nerve (7 total)
EPL, EPB, APL, EIP (deep extensors)
EDC, EDM, ECU (common extensors)
*Radial nerve proper: Brachioradialis & ECRL
*DBRN: ECRB and supinator
A patient has borderline carpal tunnel. You place the G1 ring over the 1st MCP joint. Which 2 sites do you stim? What is considered normal?
Stim: Median nerve at the wrist (between PL & FCR) and radial nerve over the dorsal, distal radius
Normal: Difference < 0.5 ms (greater is suggestive of CTS)
A patient has an ulnar lesion but sensation over the dorsal 4th and 5th fingers is spared. Where is the lesion most likely to be?
Guyon's canal; dorsal ulnar cutaneous (DUC) comes off 5-8 cm proximal to the wrist
EIP
C7, C8