Quantification of wrist joint laxity

Laxity may be a trigger for chronic unidentified wrist pain. To determine whether this is the case, first an objective method to quantify wrist laxity needs to be defined. This study investigates different quantification methods (reference tests) from the literature and compares these with the judgment of 2 independent experienced clinicians (index test, or gold standard).

Fifty healthy women (ages 19-43 y) without wrist complaints were included. For each subject, both clinicians were asked to give a laxity score for both wrists on a Likert scale of 1 to 5 (1 = very stiff, 5 = very lax). Subjects also had 3 reference tests: the Garcia-Elias method (passive range of motion), the Beighton method (general hypermobility), and the active range of motion method (specially designed measurement device).

There was no significant difference between the average laxity scores of clinicians 1 and 2. The intraclass correlation between clinician 1 and clinician 2 was significant but low. Correlation between the clinicians with the Garcia-Elias test as well as the Beighton method was significant but low (0.431 and 0.378). The correlation between reference tests was higher but still moderate.

This study showed that the index test used (clinical assessment) did not produce a satisfactory quantification of wrist laxity. Also, the reference tests are not suitable for quantification of laxity and seem to measure mobility rather than laxity. To quantify wrist laxity in a reliable and clinically relevant manner, it seems that consensus needs to be established between clinicians as to what elements of (abnormal) wrist motion define the wrist as "lax." In addition the development and testing of a measurement device that quantifies wrist translation might be needed for determining an objective score for wrist laxity.