Median Nerve. The median nerve enters the palm via the carpal tunnel, running between the flexor digitorum superficialis (FDS) and flexor carpi radialis (FCR). At the proximal border of the transverse carpal ligament (TCL), it gives off a palmer cutaneous branch (PCB) from its radial border running between the palmaris longus and FCR that provides sensation to the thenar skin. The PCB of the median nerve is at risk for injury during carpal tunnel surgery. At the distal border of the TCL, the median nerve divides into 5 or 6 branches: the recurrent motor branch to the muscles of the thenar eminence, a common digital nerve for the thumb, the proper digital nerve for the radial side of the index finger, and two common digital nerves for the adjacent areas of the index and long, and long and ring fingers respectively. The origin of the recurrent motor branch varies with respect to the TCL, with the majority being extraligamentous. It is responsible for innervating the superficial head of the FPB, the abductor pollicis brevis (APB), the opponens pollicis, and the two radial lumbricals.
lacertus fibrosus Is tightened w/ pronation of forearm as bicipital tuberosity of the radius passes posteriorly
FIGURE 6.13 Cross section of the wrist demonstrating the relationship of the carpal tunnel (CT) and the ulnar tunnel (UT). A, ulnar artery; C, capitate; H, hamate; M, median nerve, P, pisiform; PCL, palmar carpal ligament; S, scaphoid; t, flexor tendon; T, triquetrum; TCL, transverse carpal ligament; U, ulnar nerve. (Source: Szabo RM, Steinberg DR. Nerve entrapment syndromes in the wrist. J Am Acad Orthop Surg 1994;82:115â€“123 .)
Median nerve injuries
Median Nerve injuries
Dina F. El Wahaidi
March 31, 2010
Entrapment of Median nerve
Can Occur at :
1)Course in the arm
* may form accessory origin for
PT MU , thru ligament of
2) At the elbow
3) in the forearm
- sublimis bridge
4) at the wrist
5) In the hand
paralysis of the muscles supplied by it
deformity of the hand
loss of sensation
(1) Paralysis of all muscles supplied .
(2) loss of pronation of the forearm .
(3) weak flexion of the wrist .
(4) loss of the flexion & opposition of the
Above The Elbow
(1) hyper-extended thumb .
(2) adduction .
(3) flat thenar eminence .
- lat. 2/3 of the palm of the hand .
- lat. 3 ½ fingers anteriorly & their distal halves
Deformity: Ape Hand Deformity
- lat. 2/3 of the palm of the hand .
-lat. 3 ½ fingers anteriorly & their distal halves
-Paralysis of the 5 hand muscles supplied by the nerve.
-The forearm muscles escape the injury as they are supplied
Below The Elbow
Motor Affection :
Deformity : Ape Hand Deformity
Sensory Loss :
•Inability to flex IP joint of thumb
•Ape thumb deformity
It’s a Clinical Diagnose Of peripheral
neuropathy, results from compression of
the median nerve at the wrist
•Affects an estimated 3 percent of adult Americans
•Three times more common in women than in men
•High prevalence rates have been reported in persons
who perform certain repetitive wrist motions (frequent
Symptoms are usually worse at night and can awaken
patients from sleep.
difficulty in holding on to a glass or cup securely
To relieve the symptoms, patients often “flick” their
wrist as if shaking down a thermometer (Flick Sign).
Clinical Features Cont.
Pain and paresthesias may radiate to the forearm, elbow, and
Decreased grip strength may result in loss of dexterity, and
thenar muscle atrophy may develop if the syndrome is severe.
Nerve Conduction Study
Compression of the Median nerve at the elbow
• CONSERVATIVE TREATMENTS
Predicting the Outcome of Conservative Treatment
• Nonsteroidal anti-inflammatory drugs (NSAIDs)
• pyridoxine (vitamin B6)
• Orally administered corticosteroids
▫ 20 mg per day for two weeks
▫ followed by 10 mg per day for two weeks
DO NOT WORK !!!
• Should be considered in patients with symptoms that
do not respond to conservative measures and in patients
with severe nerve entrapment as evidenced by nerve
conduction studies,thenar atrophy, or motor weakness.
• It is important to note that surgery may be effective
even if a patient has normal nerve conduction studies
Complications of surgery
• Injury to the palmar cutaneous or recurrent
motor branch of the median nerve
• Hypertrophic scarring
• laceration of the superficial palmar arch
• tendon adhesion
• Postoperative infection
• arterial injury
- Proximal Forearm Compression
- Because Of :-
ligament of Struthers,
pronator teres muscle
Same Symptoms As C.T.S But Could Be
Differentiated By :
• include the distribution of the palmar cutaneous nerve
•The Tinel sign is positive at the forearm level
•The Phalen maneuver does not provoke symptoms
•Patients may experience pain with resistance to
contraction of the pronator teres or flexor digitorum
Anterior Interosseous Syndrome
inability to flex either the thumb interphalangeal joint or the
index-finger distal interphalangeal joint .
In contrast to those with pronator syndrome, these patients
do not complain of numbness or pain . WHY ?