Abstract
Aim
To evaluate the correlation between the clinical Kirk Watson test and arthroscopic Geissler classification in scapholunate instability.
Methods
All patients undergoing wrist arthroscopy between April 2006 and April 2010 were evaluated. Patients were included in the study if they had a Kirk Watson test and a wrist arthroscopy with an assessment of the stability of the scapholunate joint using the Geissler classification. Patients who had a Kirk Watson test performed with subsequent normal scapholunate joint at arthroscopy were included as a control group. Geissler grades 1 and 2 and grades 3 and 4 were grouped for further analysis into low and high grade instability groups respectively.
Results
76 patients were included in the study. 62 had scapholunate pathology and 14 had normal arthroscopic examinations of the stability of the joint. A positive test was found in 30% (3) of patients with grade 1 instability, 29% (4) with grade 2, 60% (12) with grade 3 and 78% (14) with grade 4 instability demonstrated at arthroscopy. The test was positive more commonly in those with grade IV instability compared with others (78% vs. 43%; p=0.015). There was a higher number with a negative test in the low grade instability group (71% vs. 32%; p=0.01) and a higher number with a positive test in the high grade instability group (68% vs. 29%; p=0.006). The test was most sensitive (78%) and most specific (57%) for those classified with Geissler grade IV instability and sensitivity and specificity were also high for those with high grade instability (68% and 66% respectively).
Conclusions
The Kirk Watson test is a sensitive and specific test for diagnosis of higher grade instability of the scapholunate joint. We found a positive correlation between increasing scapholunate instability when assessed using the Geissler classification and positivity of the test. This confirms that the Kirk Watson test can be a useful test in the assessment of those with symptomatic instability of the joint and may reflect damage not only to the scapholunate ligament but to the secondary stabilisers of the joint as well.
