Introduction

Biomechanics/Anatomy

Ulnar nerve: Anatomy
  • Arises from: C8 and T1 roots (± C7)
  • Axons travel through the
    • Lower trunk & medial cord of brachial plexus
    • Ulnar groove at the elbow
    • Cubital tunnel under the flexor carpi ulnaris
    • Guyon's canal: Between the pisiform & hamate bones of the hand
    • Branches: distal to elbow
      • Forearm
        • Flexor carpi ulnaris
        • Flexor digitorum profundus (4th & 5th fingers)
        • Palmar cutaneous sensory to proximal ulnar palm
        • Dorsal ulnar cutaneous to 5th & ulnar side of 4th finger
      • Hand: (Motor innervation)
        • Palmaris brevis
        • Interossei
        • Lumbricals (3rd & 4th)
        • Flexor pollicis brevis

external image 750px-Brachial_plexus_color.svg.png

Ulnar nerve entrapment is defined as the compression of the ulnar nerve involving parasthesia radiating to the 4th and 5th digits. The mechanism of injury can be compression of the nerve or entrapped due to overuse or direct trauma to the elbow. Repetitive motions may start a cycle of inflammation and edema that may interfere with the normal gliding of the nerve. Nirschl deivided the medial epicondylar groove into three zones:
Zone I: proximal to the medial epicondyle
  • cubitus valgus
  • medial intermuscular septum
Zone II: Level of the medial epicondyle
  • subluxating ulnar nerve
  • elbow synovitis
  • cubitus valgus
Zone III: Distal to the medial epicondyle (cubital tunnel)
  • compression by tight flexor carpi ulnaris muscle
  • subluxating ulnar nerve

external image A00069F03.jpg


Signs and Symptoms

Parasthesia involving the 4th and 5th digits
Pain that may extend proximally or distally in the medial aspect of the elbow.
Pain or parasthesia that becomes worse at night (due to sleeping with a flexed elbow)
Weak pinch
Weak grasp
Claw hand of ring and little finger
Decreased sensation in the ulnar distribution of the hand
Positive Froment's Sign
Positive Tinel's Sign
Positive Elbow Flexion Test

external image Symptom_chart_II.jpg


Practical Presentation


Motor Loss
Sensory Loss
Functional Loss
  • Flexor Carpi Ulnaris
  • Medial Half of Flexor Digitorum Profundus
  • Palmaris Brevis
  • Hypothenar eminence
  • Adductor Pollicis
  • Medial two Lumbricals
  • All Interossei
  • Posterior (dorsal) and palmar aspect of little and medial half of ring finger
  • Weak wrist flexion
  • Loss of ulnar deviation at wrist
  • Loss of distal flexion of little finger
  • Loss of abduction and adduction of fingers
  • Benedict's Hand
  • Loss of thumb adduction

Ulnar Claw Hand (Benedict's Hand) due to inability to extend 2nd and 3rd phalanges of little and ring fingers.
external image claw%20hand.jpg

Treatment

Conservative/Adjunct Treatment

Education
  • Activity Modification
  • Causes of ulnar nerve entrapment
  • Use of anti-inflammatories
Assistive Device
  • Night Anterior Elbow Extension Splint
  • 4-6 week period of immobilization with elbow splinted at 45 degrees flexion and neutral rotation
Figure 2
Figure 2

Manual
Exercise

Surgical

Check out the links below to see a few types of surgeries performed for ulnar nerve entrapment.

Medial Epicondylectomy: Aponeurotic origin of the flexor mass is dissected allowing partial excision of the epicondyle. The ulnar collateral ligament isn't comprimised and this can be done in addition to a simple compression.


Decompression: Release of Osborne's ligament through an incision throughout the length of the ligament increasing the space in the cubital tunnel.

Decompression Transposition of Ulnar Nerve


Anterior transposition of ulnar nerve: it effectively lengthens the nerve and decreases tension on the nerve during elbow flexion
  • Subcutaneous transposition: Nerve positioned beneath subcutaneous laye; requires 2 weeks immobilization
  • Intramuscular transposition: Nerve laid across flexor pronator muscle groups; requires 3 weeks immobilization
  • Submuscular transposition: Nerve deep to the flexor pronator muscle group and on the brachialis muscle; requires 3-4 weeks immobilization

Anterior Transposition of Ulnar Nerve




Protocols
Can expect to be in therapy anywhere from 8-12 weeks pending on prior level of function.

Phase I –Immediate Post Operative Phase (Week 0-1)
Goals
  1. Allow soft tissue healing of relocated nerve
  2. Decrease pain and inflammation
  3. Stop muscular atrophy
Week 1
  • Posterior splint at 90° elbow flexion with wrist free for motion (sling for comfort)
  • Elbow compression dressing
  • Exercises
    • Gripping
    • Wrist ROM (passive only)
    • Shoulder isometrics (no shoulder ER)

Phase II –Intermediate Phase (Week 3-7)

Goals
  1. Full ROM (pain free)
  2. Increase strength and endurance of upper extremity musculature
  3. Slowly increase functional demands
Week 3-5
  • Progress elbow ROM -- with emphasis on full extension
  • Initiate flexibility exercises for:
    • Wrist ext/flexion
    • Forearm supination/pronation
    • Elbow ext/flexion
  • Initiate strengthening exercises for:
    • Wrist ext/flexion
    • Forearm supination/pronation
    • Elbow ext/flexors
    • Shoulder program (Thrower’s Ten Shoulder Program)
Week 6-7
  • Continue all exercises listed above
  • Initiate light sport activities

Phase III –Advanced Strengthening Program (Week 8-12)

Goals
  1. Improve strength/power/endurance
  2. Initiate return to sport
Week 8-11
  • Start with eccentric exercise
  • Start plyometric exercise (if appropriate)
  • Continue shoulder and elbow strengthening/flexibility exercises
  • Initiate interval throwing program for throwing athletes
Week 12
  • Return to competitive throwing
  • Continue Thrower’s Ten Exercise Program

Phase IV –Return to Activity (week 14-32)

Goals
  1. Gradual return to activities

Adapted from
http://www.newyorkortho.com/2011PT_PDF/elbowfolder/Post%20Operative%20Rehabilitation%20Protocol%20Following%20Ulnar%20Nerve%20Transposition.pdf

Exercises

external image xgolfers.jpg


http://www.summitmedicalgroup.com/library/sports_health/medial_epicondylitis_exercises/



Modalities


Ultrasound: parameters below increased recovery rate of nerve
  • Intensity: 0.5 W/cm2
  • Frequency: 1.0 MHz
Cryotherapy: to decrease inflammation and swelling

Works Cited
http://neuromuscular.wustl.edu/nanatomy/ulnar.htm
http://en.wikipedia.org/wiki/Brachial_plexus (image only)

http://www.physio-pedia.com/Cubital_Tunnel_Syndrome_II#cite_note-Lund-12
Lund, A.T., & Amadio, P.C. (2006). Treatment of cubital tunnel syndrom:perspectives for the therapists. J Hand Ther, 19(2), 170-178.
Stern, M, & Steinmann, S.P. (2009). Ulnar nerve entrapment:treatment. Orthopedic Surgery, Mayo Clinic of Rochester, Retrieved from http://emedicine.medscape.com/article/1244885-treatment
Loudon, J, Swift, M, & Bell, S. (2008). The clinical orthopedic assessment guide second edition. Human Kinetics.
Dutton, M. (2008). Orthopaedic: examination, evaluation and intervention 2nd edition. United States of America: McGraw-Hill Companies Inc.
Palmer, B.A., & Hughes, T.B. (2010). Cubital tunnel syndrome. J Hand Surg Am, 35(1), 153-63.