Hand: Scaphoid nonunions

Fractures of the scaphoid bone tend to be problematic because of the lack of plentiful blood supply to this bone. The scaphoid is covered by bloodless cartilage on most sides, with the blood supply coming from tenuous sources that can easily be disrupted by the fracture itself. A fracture of the waist of the scaphoid can cause one half of the bone to starve for blood, and therein lies the problem.

Case study 1

Hand: A chronic scaphoid nonunion

This is the case of a male in his 20's who presented with a chronic nonunion of the left scaphoid. He had neglected his initial wrist injury because he thought it was "just a sprain." Eventually he decided to seek care due to continued pain which interfered with his work.

Xrays show a chronic scaphoid nonunion.

An MRI was done and it showed that both fragments of the scaphoid were perfused, i.e. without avascular necrosis.

I proposed surgical treatment with a vascularized graft. The 1-2 ISCRA graft technique is well described and was my preferred treatment method.

A cube of distal radial bone graft with the vascular pedicle is harvested. In the picture below, the fingers are to the left, the elbow is on the right.

The bone cube is placed in the volar part of the scaphoid gap after the nonunion surfaces were thoroughly scraped. A differential pitch screw (Acutrak) is inserted to hold the alignment. The picture below shows the closed dorsal gap in the scaphoid. The fracture line is between my instruments.

The patient was in a cast for 3 months.

The xrays below are done at 4 months after surgery. The fracture appears healed.

Xrays close to 4 years later

The take-home point again is this: Pain in the wrist after a fall should not be neglected.

Case study 2

The xrays below show a scaphoid fracture that has not healed. The prior surgery has not worked. At 7 months after the first surgery, xray shows nonunion, with "windshield wiper effect" in the distal scaphoid.

My treatment was to remove the first screw, scrape out the fracture gap, fill the void with ICBG (iliac crest bone graft), and restabilize the fracture with a bigger screw. And that's what I did. Out came the Acutrak micro, in went an Acutrak mini screw.

These are the xrays 6 weeks after the second surgery.

A study of more than 300 adolescent scaphoid fracture was published on JBJS (by Gholson et al) right around this time. According to the study, the good doctors at Boston Children's Hospital were surprised to find that the presence of open physes was associated with "increased time to union."

In other words, fractures of the scaphoid bone in teenagers apparently take a lot longer to heal than in adults! Typically, if you have "open physes," that is to say if you are really young, your bones will heal a lot faster than if you were a full grown older adult. Not so for the scaphoid apparently.

And so this young lady wore the cast for 6 months after the second surgery.

And she eventually healed.

The following xray was done two months after hardware removal.

The treatment process took one year. The moral of the story here is this: displaced scaphoid fractures are inherently problematic.