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Case (66)

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Dr.Habiib:
A 12-year old boy fell of his skateboard, hitting his right   elbow on the road.  He felt a considerable pain and   numbiness on the ulnar side of his hand. On examination, the doctor found that there    was sensory loss of right little finger and medial border of his palm.
The boy was unable to grip a piece of paper placed between his fingers. The doctor suspected elbow fracture and peripheral nerve damage. On radiograph a considerable displacement of his epiphysis of the medial epiconyle was noticed.
1. What is the probably injured?
2. Why we consider the case an epiphyseal separation rather than epiphyseal fracture?
3. Why was sensory loss of the little finger?
4. Why the boy unable to grip a paper placed between his fingers?
5. What   movements of the thumb possibly lost?
  

Dr. Acromion:


1.The boy must have sustained .........Ulna nerve injury,  the most poorly protected nerve in the body.

2. Ossification of th ulna bone occurs in the extreme ends of the bone, the upper epyphyseal joins the body at about the sixteenth year where's the lower one around the age of the twenty .............and the boy in question is only 12 years old , that gives us enough ground to consider epiphyseal separation rather.

3. Because the ulna nerve is resposible for sensory supply the little finger and the lateral half of the ring finger. Damage to the nerve causes numbness to the little finger principally.

4. All the intrinsic muscles of the fingers are paralysed as they are supplied by the ulna nerve (apart from the radial two lumbricalis), and the hand assumes a clawed position (main en griffe)...........hence unable to grasp/grip well.

5. Disability of the adduction would be expected, this may not be very obvious as it can be compensated to some degree by other muscles. Froment's sign is also positive in this patient.

(Froment's sign is a test for ulnar nerve palsy which specifically tests the action of adductor pollicis.

The patient is asked to hold a piece of paper between the thumb and a flat palm as the paper is pulled away. Normally an individual will be able to hold the paper there with little or no difficulty. However, the patient with an ulnar nerve palsy will flex the thumb to try to maintain a hold on the paper.)


 

Dr.Habiib:
Thank   you    Dr. Acromion   you got 100%   excellent.
Answers:
1. The nerve was injured is ulnar nerve.

2. The condition is considered epiphyseal separation because the medial epicondyle fuses with side of diaphysis at the age of 16 years in boys and 14 years in girls. In this case we have a boy less than 16 years.

3. The ulnar nerve was injured.  The ulnar nerve supplies sensory fibers to medial one and half fingers hense the loss of sensations of little finger.

4.The ulnar nerve supplies the palmar interossei muscles which are adductors to fingers so the boy was unable to grasp the paper placed between his fingers.

5. Adduction of thumb is lost due to paralysis of adductor pollicis muscle.

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