1. Entrapment Neuropathy
Dr. Fadel Naim
Orthopedic Surgion
IUG

2. DEFINITION
Entrapment Neuropathy is defined as: Pressure or Pressure induced injury to a segment of a peripheral nerve secondary to anatomical or pathological structures

3. Common Causes Entrapment Direct Injury Systemic disease
Adjacent soft tissue structures
Aberrant bone growths
Fluid cysts
Edema
Prolonged poor positioning
Poor fitting orthotics
Direct Injury
Systemic disease 3

4. Entrapment neuropathy is caused by the direct pressure on a single nerve.
Earliest symptoms to occur: tingling & neuropathic pain.
Followed by reduced sensation or complete numbness
Muscle weakness is noticed later, followed by muscle atrophy.

5. Clinical scenario Either or all Pain Numbness Tingling Burning
Weakness
Muscle wasting(severe cases)
in respective anatomical areas

6. ENTRAPMENT NEUROPATHIES OF THE UPPER LIMB

7. Cervical Radiculopathy
Spinal nerve root dysfunction - Root compression from protruded or herniated cervical intervertebral disc
Nerve root signs:
Paresthesias
decreased reflexes
sensory loss,
weakness in distribution of compressed nerve root
Spinal cord compression:
spastic paraparesis with hyperactive DTRs
Neck pain, muscle spasm
C7 most common (31-81%)
C6 (19-25%), C8 (4-10%), C5 (2-10%)

8. Brachial Plexus Injuries Etiology
traffic accidents
birth injuries
humerus luxations
brachial plexus neuritis
stab and bullet wounds
tumors (especially lung cancer)
cervical rib, fibrous band from C7 (neurogenic thoracic outlet syndrome)

9. Upper Lesions of the Brachial Plexus (Erb’s Palsy)
Resulting from excessive displacement of the head to opposite side and depression of shoulder on the same side.
This causes excessive traction or even tearing of C5 and 6 roots of the plexus.
It occurs in infants during a difficult delivery or in adults after a blow to or fall on shoulder.

10. Upper Lesions of the Brachial Plexus (Erb’s Palsy)
It is due to over traction on the neck as in:
Shoulder dystocia.     
After-coming head in breech delivery.

11. Upper Lesions of the Brachial Plexus (Erb’s Palsy)
Motor: paralysis of
the supraspinatus,
infraspinatus,
subclavius,
biceps brachii,
part of brachialis,
coracobrachialis;
deltoid
teres minor.
Sensroy: sensory loss on the lateral side of the arm.

12. The usual clinical appearance:
Upper limb with:
An adducted shoulder
Medially rotated arm
Extended elbow.
(policeman’s or waiter’s tip hand)
The lateral aspect of the upper limb also experiences loss of sensation

13. Lower Lesions of the Brachial Plexus (Klumpke Palsy)
Injuries to inferior parts of the plexus are much less common.
Lower brachial plexus injuries may occur when the upper limb is suddenly pulled superiorly
When a person grasps something to break a fall
A baby's upper limb is pulled excessively during delivery

14. Lower Lesions of the Brachial Plexus
(Klumpke Palsy)
Motor Effects: paralysis of all the small muscles of the hand.
Sensory effects: loss of sensation along the medial side of the arm.
deformity: claw hand caused by hyperextension of the metacarpophalangeal joints and flexion of the interphalangeal joints.

16. MEDIAN NERVE
3 important compression neuropathies from distal to proximal
CARPAL TUNNEL SYNDROME
ANTERIOR INTEROSSEOUS SYNDROME
PRONATOR SYNDROME

18. ETIOLOGY DECREASE IN SIZE OF CARPAL TUNNEL
INCREASE IN CONTENTS OF CANAL
Forearm & wrist fractures
Dislocations & subluxations
Post traumatic arthritis (osteophytes)
Local tumours (neuroma, lipoma, ganglion, cysts, multiple myeloma)
Hyrertrophic synovium
Hematoma

19. ETIOLOGY NEUROPATHIC CONDITIONS INFLAMMATORY CONDITIONSDM
Alcoholism
Double crush syndrome
Exposure to industrial solvents
INFLAMMATORY CONDITIONS
Rheumatoid arthritis
Gout
Non specific tenosynovitis
Infections
EXTERNAL FORCES
Vibration
Direct pressure

20. Double Crush Syndrome

21. ETIOLOGY ALTERATIONS OF FLUID BALANCE Pregnancy Menopause Eclampsia
Thyroid disorders (esp. hypothyroidism)
Renal failure
Long term hemodialysis
Raynaud’s disease
Obesity

22. Carpal Tunnel Syndrome
The median nerve is the most sensitive structure
Paresthesia, hypoesthesia may occur in the lateral three and a half digits.
Progressive loss of coordination and strength in the thumb ( recurrent branch which serves three thenar muscles)
Difficulty performing fine movements of the thumb

23. Sensory domain and muscular atrophy

24. CLINICAL FEATURES Tinel’s sign: Phalen’s test:
percussing the median nerve at the wrist.
Phalen’s test:
Patient places elbow on table, forearm vertical with wrist flexed.
Numbness & Tingling in median nerve distribution occurs in 60 seconds in + ve cases.

25. Carpal Tunnel Syndrome
As the condition progresses, sensory changes radiate into the forearm and axilla.
Reproduction of symptoms
Compression of the median nerve with your finger at the wrist for approximately 30 seconds.
Partial or complete carpal tunnel release may be necessary

27. ANTERIOR INTEROSSEOUS SYNDROME
Anterior interosseous branch of the median nerve supplies the flexor digitorum profundus to the index finger, flexor pollicis longus & pronator quadratus.
Provides sensation to the volar aspect of carpus.

28. ANTERIOR INTEROSSEOUS SYNDROME
POTENTIAL SITES OF COMPRESSION:
Fibrous bands of the flexor digitorum superficialis
Fibrous bands of the deep or superficial heads of the pronator teres.
LESS COMMMON CAUSES
Anomalous muscles
Enlarged / thrombosed vessels
Tumours
Enlarged bursae

29. ANTERIOR INTEROSSEOUS SYNDROME
CLINICAL FEATURES:
Weakness of flexion in the IP joint of the thumb.
Weakness of flexion in the DIP joint of index finger.
No sensory loss
Pain is exacerbated by exercise & relieved by rest.
Number of cases occur due to a viral neuropathy.
TREATMENT
INITIALLY: CONSERVATIVE
SURGICAL: INDICATIONS
No resolution of symptoms
Severe symptoms
SURGICAL EXPLORATION: Identification & division of the offending structure.

30. PRONATOR SYNDROME Anatomical sites of compression:
Below lacertus fibrosus
Between the 2 heads of pronator teres

31. CLINICAL FEATURES
Ache or discomfort in the fore arm associated with weakness or clumsiness of the hand.
Numbness in the distribution of the median nerve.
Night pain is not common.
Phalen’s test & Tinel's sign: negative
Difficult to demonstrate electrophysiological abnormality.

32. TREATMENT CONSERVATIVE: SURGICAL: NSAID’S
Splinting with the elbow at 90 degrees, slight forearm pronation & wrist flexion.
SURGICAL:
Exploration of distal 5 to 8 cm of the course of the median nerve in the arm combined with its course in the upper forearm.

33. Ulnar Nerve Entrapment
Elbow ( Cubital Tunnel Syndrome)
2nd most common entrapment neuropathy
Entrapment at the ulnar groove or cubital tunnel (two heads of the flexor carpi ulnaris)
Sensory changes of 4th and 5th digits
Failure of active finger extension in ring (3rd) and”(4th)
Clawhand if loss of all intrinsics

34. Clawing of the ring and small finger due to ulnar nerve dysfunction.

37. Ulnar Nerve Entrapment
Hypothenar eminence (Guyon’s Canal Syndrome)
Compression of the ulnar nerve
Where it passes between the pisiform and the hook of the hamate. (Guyon's canal)
May result in hypoesthesia in the medial one and a half digits
Weakness of the intrinsic muscles of the hand.

39. RADIAL NERVE POSTERIOR INTEROSSEOUS NERVE SYNDROME
RADIAL TUNNEL SYNDROME
WARTENBERG’S SYNDROME

40. POSTERIOR INTEROSSEOUS NERVE
ANATOMY
Proximal to the elbow joint, the radial nerve branches into the superficial radial nerve & the PIN.
The PIN travels around the radial neck and through the interval between the 2 heads of the supinator muscle.
This opening which has an overlying compressive fibrous arch is known as arcade of frosche.

41. RADIAL TUNNEL SYNDROME
Pain is often acute & can mimic tennis elbow.
Electrophysiological studies shows no abnormality.
Treatment: non-operative: Activity modification, splinting, NSAID’S & rest.
Surgical decompression is often combined with lateral epicondyle release.

42. WARTENBERG’S SYNDROME
Compression of the superficial branch of the radial nerve can occur most commonly as it exits from beneath the brachioradialis in the forearm.
Nerve can get trapped b/w the ECRL & the brachioradialis, especially with pronation in the forearm.

43. CLINICAL FEATURES TREATMENT
Numbness and / pain in the dorsal & radial aspects of the hand.
Positive Tinel's sign
Symptoms can be further elicited by forceful pronation of the forearm.
Conservative: activity modification, NSAID’S, Steroid injections, splinting & occupational therapy.
Failure of conservative therapy: surgical exploration & decompression.
TREATMENT

44. Suprascapular Nerve. Entrapment
Throwers, other overhead athletes and weight-lifters
Arises from superior trunk of brachial plexus
Innervates supraspinatus and infraspinatus
Compression most commonly suprascapular notch

45. Etiology Notch narrowing Ganglion cyst from intraarticular defect
Nerve kinking or traction from excessive infraspinatus motion
Superior or inferior transverse scapular ligament hypertrophy causing compression

46. Clinical Vague posterior shoulder pain, weakness and fatigability
Weakness/atrophy without pain often suggests compression
Symptoms may mimic rotator cuff pathology or instability
Exam reveals rotator cuff weakness and possibly supra- and/or infraspinatus atrophy

47. Infraspinatus atrophy

48. Diagnosis and Treatment
MRI may exclude rotator cuff tears, demonstrate atrophy and/or reveal a ganglion or space-occupying
Typically begin with non-operative mgmt.
Rest from repetitive hyperabduction
NSAIDs and corticosteroid injections
Nonresponders may benefit from
a notchplasty
transverse scapular ligament release
nerve decompression

49. THORACIC OUTLET SYNDROMES
Thoracic outlet syndromes are caused by compression of the neurovascular structures passing through the thoracic outlet.

50. Thoracic Outlet syndrome

52. Investigations
Plain films may reveal a cervical rib or exuberant callus from a clavicle/upper rib fx

53. ENTRAPMENT NEUROPATHIES OF THE LOWER LIMB

54. Sciatic nerve Consist of these parts : Main trunk.
Common peroneal nerve.
Tibial nerve.
In 90% of injuries, the common peroneal part of the nerve is the most affected

55. Main Trunk (causes of injury)
Most common in misplaced therapeutic injections into gluteus maximus.

56. Causes of injury Nerve palsy
complete palsy of the sciatic nerve is rare and usually related to trauma (penetrating wounds, fractures of the pelvis, posterior dislocation of the hip)

57. Causes of injury piriformis syndrome
External compression over the buttock (e.g. in patients who lie immobile on a hard surface for a considerable length of time).

58. Causes of injury
3- SCIATIC NERVE INJURY IN INTERVERTEBRAL DISC PROLAPSE.

59. Diagnosis of main trunk injury
Sensation is lost below the knee, except area supplied by the saphenous nerve (from femoral nerve).

60. common peroneal nerve injury
The common peroneal nerve is relatively unprotected as it traverses the lateral aspect of the neck of the fibula and is easily compressed at this site, e.g. by plaster casts and injury during knee surgery

61. Causes of injury
2- The nerve may also become entrapped between the attachments of peroneus longus to the head and shaft of the fibula.

62. Causes of injury (cont…)
3-Fracture of fibular neck

63. Causes of injury (cont…)
4- The most common etiology is Habitual leg crossing

64. Causes of injury
5- The superficial peroneal nerve may be involved in compartment syndrome affecting the lateral compartment.

65. Common peroneal nerve (diagnosis of injury)
Loss of sensation occurs
the anterior and lateral sides of the leg
dorsum of the foot and toes, including the medial side of the big toe.

66. Diagnosis (cont…)

67. Tibial nerve (causes of injury)
The tibial nerve is vulnerable to direct injury in the popliteal fossa, where it lies superficial to the vessels at the level of the knee.
1- The tibial nerve is commonly injured by fractures or other injury to the back of the knee or the lower leg

68. Causes of injury (cont…)
2- It may be damaged in compartment syndrome affecting the deep flexor compartment of the calf.

69. causes of injury (cont…)
3- The tibial nerve and its terminal branches, the medial and lateral plantar, and medial calcaneal can be entrapped beneath the flexor retinaculum at the ankle, resulting in tarsal tunnel syndrome

70. (diagnosis of injury) Tibial nerve
Loss of sensation occurs
1-lower posteriolateral side of leg (innervated by sural nerve).
2-whole sole of foot.

71. Diagnosis of injury (cont…)

72. Obturator nerve (causes of injury)
The Obturator nerve is rarely damaged
Causes
Penetrating wounds.
Anterior dislocation of hip joint.
Abdominal herniae through the obturator foramen.
It may be pressed on by the fetal head during parturition .

73. Obturator nerve (diagnosis of injury)
The cutaneous sensory loss is minimal on the medial aspect of the thigh.

74. Meralgia paresthetica
Compression on lateral cutaneous nerve of the thigh
common in men than in women
Paraesthesiae and often burning pain over the anterolateral aspect of the thigh.
Pregnancy, tight clothing (tight, low-rise jeans), leaning against table for hours while working, policemen belts.
Prolonged standing, or sitting may provoke symptoms
DR FADEL NAIM
IUG