Effect of combined conservative therapies on clinical outcomes in patients with thumb base osteoarthritis: a randomised, controlled trial (COMBO)

The intervention will be composed of four components: EDUCATION ABOUT THE DISEASE AND JOINT PROTECTION TECHNIQUES All participants will be provided with education about disease and joint protection techniques through an educational brochure delivered at baseline and through face-to-face meetings of approximately 30 minutes each with the study therapist at baseline and 2-week visit. The brochure and the visit will aim to provide information about the disease including: diagnosis, disease course, objectives of treatment, self-management and instruction in joint protection techniques. The brochure was developed by a team of health professionals involved in this study (occupational therapists, physiotherapists and rheumatologists) with experience in the management of thumb base OA. The therapist will have a script to follow in order to be consistent with all participants regarding the joint protection advices. SPLINTS We will use prefabricated neoprene splints incorporating the base of the thumb and wrist and recommend its use during the activities of daily living (minimum of 4 hours/day) for 6 weeks, removing during rest, sleep, exercises, bathing and heat activities. EXERCISES The aim of the exercise programme in our study will be to optimize the range of motion (ROM) and joint stability, to increase strength and to prevent progression of deformities and loss of ROM. The programme will be consisted of five exercises: thumb opposition; paper tearing; line tracing on ball; objects collection with chopsticks and ball squeezing. Participants will receive instructions on how to do the exercises correctly through a supervised one-on-one 30 minute sessions with the study therapist at baseline and at two weeks after intervention commencement. They will be further instructed to perform individual unsupervised at-home sessions, three times per week for 6 weeks. Each exercise should be repeated 10 times during the first week. For the strength exercises (paper tearing and ball squeezing), the progression will be made by increasing the difficulty (e.g. tearing a thicker paper and squeezing the ball harder). For the remaining exercises, the number of repetitions will be increased, aiming for 12 repetitions during the second week and 15 repetitions for the following 4 weeks, if tolerated. Each home exercise session should last approximately 10 minutes. TOPICAL NSAIDS The usual prescription of topical NSAIDs for patients with hand OA involves the application of the medication over the affected joint three times a day. For the purpose of this trial, we will use Diclofenac diethylammonium gel (11.6 mg/g), a topical NSAID commonly used in clinical practice that has been studied in large, good quality trials with superiority over placebo . Participants will be instructed to administer the medication three times per day immediately prior to placing the splint for 6 weeks on a daily basis. In order to standardise the amount used, the participants will receive a small spatula with a permanent pen mark showing exactly how much product they should use. The advised amount corresponds with approximately 20 mg to be applied in an area of 40 cm2 as recommended by the drug instructions. The use of the medication for 6 weeks in this study and not for a shorter period of time is justifiable due to the chronic nature of OA. The topical NSAID will be free of charge. To monitor adherence to the treatments, participants from the intervention group will receive a diary and will be asked to record their use of splints and topical NSAIDs on a daily basis. In addition, the participants will be requested to report which exercises were performed and how frequently they were performed on a weekly basis. Participants will be asked to bring their diaries in for the re-assessment visits.