1. Open Fracture of the Hook of the Left Hamate
Jamie McDonald
Case Study

2. Outline Open Fracture to Hook of Left Hamate Ulnar Artery
Causes
Symptoms & Complications
Treatment
Ulnar Artery
Pathway
Relation to Ulnar Nerve
Clinical Application

3. The hamate bone is a triangular-shaped bone composed of a body and a hook. Hamate fractures are classified as type 1 fractures involving the hook.

4. Causes
Type 1 fractures involving the hook of the hamate are most common.
Repeated microtrauma to the hook during sports involving swinging clubs, bats, or racquets.
Direct trauma can occur when the butt of the club rests on the hamate, and the force from the swing transfers directly to the bone.
Indirect trauma can occur by falling on a hyper-extended wrist or during power grips, thus injuring the muscles and ligaments.

5. Symptoms & Complications
Pain in wrist.
Decreased grip strength.
Pain on palpation of the hook of the hamate.
Numbness in fourth and fifth fingers.
Tenderness on the palm side of wrist.
Pain on the little finger side of wrist
Complications:
Damage to the ulnar nerve and artery.
Infections

6. Treatment
Open Reduction (surgery): Only necessary if there is a deformity; completed through an incision and use of pins and screws.
Physical & Occupational Therapy: joint mobilizations; soft tissue massages; ultrasound; bracing; strength activities.
Immobilization in a short arm cast for at least 6 weeks.
Ultrasound

7. Ulnar Artery
The ulnar artery leads down the ulnar side of the forearm to the wrist, supplying blood to the flexor and extensor muscles in the lower arm. Branches of the ulnar and radial arteries combine at the wrist to supply structures in the wrist, hand, and fingers.

8. Ulnar Nerve
The ulnar nerve is a branch of the brachial plexus nerve system. It helps provide motor movement to the flexor muscles of the hand, allowing bending.

9. Relation
The ulnar nerve travels through cubital tunnel on the medial side of the elbow. It supplies the flexor carpi ulnaris and the flexor digitorum profundus muscles and courses with the ulnar artery.
At the hand, the ulnar nerve enters through the Guyon’s canal.
If the ulnar nerve is damaged at the wrist, the ulnar claw can result.

10. What Is Ulnar Claw?
A deformity that is seen in ulnar nerve damage at the wrist.
Affects the little and ring finger of the hand.
When the medial lumbricals are paralyzed, flexion is lost at the MCP joints and extension is lost at the IP joints.
MCP joints are hyper-extended.
IP joints are flexed.
There is an imbalance between the intrinsic and extrinsic muscles of the hand.

11. Intrinsic muscles- curling of fingers
Extrinsic muscles- stretches MCP joints backwards
Lumbrical Position in splint for MCP joints

12. The Case Patient is a 49 year old male in good health.
Victim of a gunshot wound to the left hand.
Open left fracture of the hook of the hamate.
Reports the chief complaint is pain, decreased range of motion, and decreased strength in the left hand and wrist.
Surgery performed on May 21, 2016.

14. Hand before surgery was performed.

15. X-ray before surgery: fracture of the hook of the hamate.

16. History Gun shot to hand 5/20/16: Surgery 5/21/16:
Dorsal Blocking splint fabricated
5/24/16:
1st day of therapy
Last day seen
6/22/16:
Beginning of ulnar clawing
6/7/16:

17. Post-Surgery Cast on hand, wrist, and forearm to prevent:
Intrinsic minus: bad positioning in splint
Hand held in lumbrical plus position with dorsal blocking splint.
MCP joint flexion
IP joint extension
Nerve response to injury:
Dry, callus skin
Peeling
Discharge and pale color

18. X-ray after surgery

20. Post surgery ulnar clawing: MCP joints are hyperextended; IP joints are flexed

21. Dorsal Blocking Splint

22. Occupational Therapy Correct positioning in dorsal blocking splint.
Stretching of extrinsic flexors and extensors to prevent tightness.
If MCP joints collateral ligaments are taught- extension- leads to stiff joints
If MCP joints are lengthened- flexion- range of position is promoted
Goal of therapy is for the thumb to touch the tip of the pinky.

23. What’s Next? Last day seen in therapy was 6/22/16. Ulnar nerve:
Continues to repair itself
Will grow 1 inch per month, following the first month.
Range of motion:
When the fingers gain ROM back, therapy will incorporate more strengthening exercises.
Possible deformity of hand and loss of wrist/hand movement.

24. References http://emedicine.medscape.com/article/97813-overview#a6
injuries/fracture-of-hook-of-hamate
new.html#full-description
nters_clinics/peripheral_nerve_surgery/conditions/ulnar_ner ve_entrapment.html
hand-of-benediction/
Ulnar Intrinsic Anatomy and Dysfunction
Dell, Paul C.Sforzo, Christopher R. et al.
Journal of Hand Therapy , Volume 18 , Issue 2 , 198 – 207.