Objective: To determine the difference in the usability of three types of thenar eminence (TE) orthoses.
Design: Prospective comparative pre-experimental study with randomized cross-over design.
Setting: Rehabilitation centre.
Subjects: Ten patients with osteoarthritis of the carpometacarpal I joint confirmed by X-ray.
Intervention: Three types of TE orthoses, made of either supple elastic material, elastic material with a semi-rigid thumb busk or a semi-rigid (polyethylene) material.
Main outcome measurements: Pain at the thenar eminence, pinch force, hand function, cosmesis, comfort and function of the TE orthosis.
Results: The supple elastic TE orthosis scores significantly better than the more rigid types on the subjects 'comfort', 'function' and the Green Test, while the semi-rigid orthosis scores best on 'cosmesis'. The score on the subject 'pain reduction' shows no significant difference between the three types of TE orthoses. The scores obtained correspond with the outcome of structured interviews about the usability of the TE orthoses.
Conclusion: Eight out of 10 patients prefer the permanent use of a TE orthosis. Six patients chose the supple elastic orthosis and two chose the semi-rigid orthosis.