Chronic Hook Of Hamate Fracture

HPI:
Young adult presents with distal left 5th digit discoloration after a sporting event. He felt intermittent sharp pain in the ulnar portion of his left hand but otherwise no other complaints immediately following the injury. The following day, he had discoloration of his left 5th digit but the pain resolved.

EXAM:
Purplish discoloration present in the left 5th digit distal to the DIP. Allen’s test reveals reduced ulnar blood flow. No pain to palpation of any portion of the hand. Flexion/extension intact in all left hand joints. 2 point discrimination reduced in the left 5th digit. Doppler flow present in the superficial blood vessels.

IMAGING:
Best seen with a carpal tunnel view. Also obtain an AP view.

MANAGEMENT:
Non-operative
- Acute hook or body fractures
- 6 weeks immobilization

Operative
- Excision of hamate fracture fragment
- Chronic hook of hamate with non-union
- neurovascular compromise
- ORIF with very little benefit

DISCUSSION/PEARLS:
- This was most likely a chronic fracture with resulting non-union and was reinjured.
- Surgical findings included engorged veins and arteries
- Associated with golf and baseball injuries
- Usual presentation: Hypothenar pain to palpation
- Pain with tight grip and decreased grip strength
- In Chronic cases: Ulnar nerve compression resulting in 4th, 5th digit paresthesias
- Rarely: Ulnar artery thrombosis

KEY POINTS
- Consider with ulnar sided hand pain with golf and baseball injuries
- Pain with grip strength
- Obtain a carpal tunnel view
- Hamate body fracture very rare, hook fracture much more common
- Non-union results in chronic ulnar nerve symptoms
- Non-operative management is appropriate if acute without any neurovascular compromise
- Operative management involves excision of fractured portion. 

By Dr. Mohammad El Kara

REFERENCES:
http://openi.nlm.nih.gov/detailedresult.php?img=2904904_256_2009_842_Fig1_HTML&query=null&req=4&npos=-1
http://www.orthobullets.com/hand/6035/hook-of-hamate-fracture