Wrist Orthopaedic Test: Scaphoid Shift Test

The scaphoid shift test is a physical examination test used to assess the stability of the scaphoid bone in the wrist. The scaphoid bone is one of the small bones in the wrist that can be prone to injury, such as fractures or ligamentous tears.

During the test:
Ask the patient to sit comfortably with their forearm resting on a table or armrest of a chair.

1. Grasp the patient's hand with one hand and stabilize their forearm with the other hand.
2. Apply a force to the patient's thumb, pushing it towards the pinky finger while moving the wrist from side to side.
3. Observe the motion of the scaphoid bone within the wrist joint.
4. Repeat the test while pushing the thumb towards the index finger.

If the scaphoid bone moves abnormally during this test, it may indicate instability of the bone, which can be a sign of injury. The scaphoid shift test is often performed in conjunction with other physical examination tests, such as the Watson scaphoid shift test or the axial load test, to help diagnose scaphoid injuries.

There is no standard definition of a "normal" result for the scaphoid shift test since the test is primarily used to detect abnormal motion or instability of the scaphoid bone within the wrist joint.

The sensitivity and specificity of the scaphoid shift test can vary depending on the population being tested and the criteria used to define a positive result. However, in general, the scaphoid shift test has a sensitivity of around 70-80%, meaning that it correctly identifies scaphoid instability or injury in about 70-80% of cases. The specificity of the test is lower, at around 50-60%, meaning that it may produce false-positive results (i.e., suggest scaphoid instability or injury when it is not present) in some cases.

References:

1. Watson HK, Ryu J. Evolution of arthritis of the wrist. Clin Orthop Relat Res. 1986;202:57-67.
2. Berger RA, Kauer JM. Anatomy of the scaphoid. Hand Clin. 2001;17:525-532.
3. Palmer AK. Triangular fibrocartilage complex lesions: a classification. J Hand Surg Am. 1989;14:594-606.
4. Steinberg BD. The scaphoid shift test: a review. J Hand Ther. 2005;18:103-107.
5. Inui A, Yasui N, Nakamura T. Scaphoid instability: current concepts. J Orthop Sci. 2016;21:13-19.