A Camera-Based System for Determining Hand Range of Movement Measurements in Rheumatoid Arthritis

Introduction

Rheumatoid arthritis (RA) is a chronic disease that mainly affects the synovial joints of the human skeleton. It is an inflammatory disorder that causes joints to produce more fluid and increases the mass of the tissue in the joint resulting in a loss of function and inhibiting movement in the muscles. This can lead to patients having difficulties performing activities of daily living (ADLs). Treatment of RA is determined by physicians through x-rays, questionnaires and other invasive techniques. An example of this would be angle measurements taken using instruments such as tape measures or a dynamometer to measure grip strength. There is no cure for RA but clinicians aim to diagnose it quickly and offer therapies which alleviate symptoms or modify the disease process. These treatment options include injection therapy, physiotherapy, manual therapy (i.e. massage therapy or joint manipulation) and drugs which can reduce the rate of damage to cartilage and bone. These treatments are assisted by patient education. Patients are shown methods of Joint Protection, educated in the use of assistive tools to aid in ADLs and shown altered working methods..

Solutions designed to facilitate and aid diagnosis of vulnerable patients – ones which are in chronic or debilitating pain, for example – face an array of unique requirements. Rheumatoid Arthritis affects around 1% of the population (Worden, 2011) and causes synovial joints in affected areas to become inflamed due to extra synovial fluid being produced. This can lead to a breakdown of the cartilage in the joints and can cause the bones in the joint to corrode. As a result, patients commonly exhibit deformation in their fingers and joints; as well as note regular and occasionally disabling pain (Majithia & Geraci, 2007). Typically, assessing patient mobility is a case of factoring in the patient attending their local medical practitioner for tests or treatment. This can become difficult however if a patient has limited mobility. For a patient who is suffering RA, it is possible that their disease is afflicting more than one set of joints in their body. Also, having the disease increases the risk of osteoporosis in the patient due to the nature of the disease and the medication they are required to take (Handout on Health: Rheumatoid Arthritis, 2009). In effect, this can mean that the patient would require home visits more commonly than a patient who is not suffering joint pain. Physicians required to visit the home of their patients in order to assess the current disease progression and possible treatments must have access to portable equipment. Therefore the equipment used must be mobile, easily set-up and be an inexpensive product. Portable low cost equipment does exist that aids treatment at home, however these methods have their own limitations that must be considered. The Jamar dynamometer has proven to be an inexpensive and reliable gauge of grip strength, providing data used in assessment. However, in patients with decreased mobility, a grip strength test would prove to aggravate their symptoms and increase levels of pain. This option is also open to false reading from patients not willing to exert their maximum grip strength due to the uncomfortable nature of the test (Richards & Palmiter-Thomas, 1996). There appears to be a lack of a measurement device that can record patients’ treatment progression that is portable, cost effective and which has maximum consideration for patient discomfort level.