Consensus on Diagnosis and Treatment of Scaphoid Fractures
Hand surgeons from Columbia University Medical Center in New York City wrote up a case study illustrating the difficulties of defining and diagnosing scaphoid fractures of the wrist. They were asked for a second opinion by a 31-year-old man who had fallen and injured his right wrist.

The patient was advised to have surgery for a diagnosis of a slightly displaced scaphoid fracture. But after doing some research on the Internet, he sought out a second opinion because he saw some information that suggested cast immobilization may be all that he needed.

The scaphoid bone of the wrist is located on the thumbside of the hand just below the radius bone of the forearm. Because the bones of the wrist are wedged together, any displacement or shift in the position of one bone changes the anatomic alignment of the wrist. Pain, loss of motion, and loss of function are common symptoms that must be addressed.

It is known that a scaphoid bone that is fractured and displaced will not heal without proper re-alignment. And there is consensus (general agreement) that the best way to accomplish this is through open surgery. The fracture is reduced (bone ends put back together) and the bone is replaced where it belongs anatomically. Fixation is used (e.g., screws) to hold it all together until healing occurs.

There is also consensus that a nondisplaced scaphoid fracture does not require surgery but can heal with cast immobilization. Screw fixation can also be helpful in these cases. But the real question is how to accurately diagnose scaphoid fracture displacement. This must be done in order to determine the best treatment approach.

There is no consensus on a definition of a nondisplaced scaphoid fracture. That may be why this patient received the first diagnosis of a "slightly" displaced scaphoid fracture. There can be a slight change in the angle of the scaphoid bone after fracture. Does that qualify for a diagnosis of displacement?

Some experts have defined scaphoid displacement by measuring the angle between the scaphoid and lunate bones. The lunate is another bone in the first row of wrist bones just below the forearm. It rests next to the scaphoid bone so a change in the angle or gap between these two bones would signal a true displacement. But once again, there is no common agreement as to the degree of angle or amount of gap that qualifies for displacement versus nondisplacement.

Some surgeons avoid the dilemma of labelling the problem as displaced or nondisplaced by using the terms stable and unstable to describe the fracture. In some studies, CT scans were added to traditional X-rays in hopes of increasing the accuracy of diagnosis. But cadaver studies showed diagnosis of scaphoid displacement using CT scans was inaccurate more often than not.

The authors concluded that all of this wrangling about terminology (separation, angulation, translation, slight displacement, minimally displaced, instability, fracture mobility) points to the need for future research to create a consensus definition of scaphoid fracture displacement. They propose that a minimally displaced fracture is still displaced and should not be labelled as nondisplaced.

In the case of this patient seeking their (second) opinion, they recommended conservative treatment with cast immobilization. The criteria they used was based on current consensus that a less than one millimeter separation with no translation and no angulation can be treated without surgical fixation.
Eric Swart, MD, and Robert J. Strauch, MD. Diagnosis of Scaphoid Fracture Displacement. In The Journal of Hand Surgery. April 2013. Vol. 38A. No. 4. Pp. 784-787.