Psoriasis is a disease in which scaly red and white patches develop on the skin (Diagram 1). It is thought to be an immune system issue that causes the skin to regenerate at faster rates. It is not known exactly why this happens, but researchers believe both genetics and environmental factors play a role.
Our body produces new skin cells in the deepest layer of skin. These skin cells gradually move up through the layers of skin until they reach the outermost level, where they die and flake off. This whole process normally takes around 3 to 4 weeks.
However, in people with psoriasis, this process only takes about 3 to 7 days. As a result, cells that are not fully mature build up rapidly on the surface of the skin, causing flaky, crusty red patches covered with silvery scales.
Diagram 1: Psoriasis
Some people with psoriasis can also develop psoriatic arthritis (PsA), manifested by painful, stiff and swollen joints. Like psoriasis, PsA symptoms flare and subside, vary from person to person, and even change locations in the same person over time.
PsA can affect any joint in the body, and it may affect just one joint, several joints or multiple joints. For example, it may affect one or both knees. Affected fingers and toes can resemble swollen sausages, a condition often referred to as dactylitis (Diagram 2). Finger and toe nails also may be affected.
PsA in the spine, called spondylitis, causes stiffness in the back or neck, and difficulty bending. It can also cause tender spots where tendons and ligaments join onto bones (Diagram 3). This condition, called enthesitis, can result in pain at the back of the heel, the sole of the foot, around the elbows or in other areas. Enthesitis is one of the characteristic features of PsA.
Diagram 2: Dactylitis
Diagram 3: Enthesitis
Recent research suggests that persistent inflammation from PsA causes joint damage later, so early accurate diagnosis is essential. Fortunately, treatments are available and effective for most people.
In addition of physiotherapy, exercise is a key life-long strategy for the management of people with inflammatory arthritis and is recommended in clinical guidelines to manage symptoms, disability and comorbidity. Recent European League against Rheumatism (EULAR) guidelines include recommendations for physical activity for people with inflammatory arthritis, including PsA. General physical activity recommendations include four domains (cardiorespiratory fitness, muscle strength, flexibility and neuromotor performance) and are applicable (feasible and safe) to people with inflammatory arthritis, including PsA. For those with PsA, the Canadian Spondylitis Association also recommends exercise, including physical exercise (≥ 150 min of moderate intensity aerobic physical activity/ week), muscle strengthening exercise, stretching exercise, heat or cold applications and kinesiotherapy to maintain range of motion.
Thermotherapy, which includes cryotherapy and heat, may be used to treat joint pain and to reduce swelling and tenderness in inflamed joints. Paraffin baths are usually useful to reduce pain in hands and feet.
2. High intensity interval training (HIIT)
Thomsen et al. performed a clinical trial aimed to evaluate the impact of HIIT on disease activity and disease perception in patients with PsA and to evaluate whether a potential effect could be sustained for a longer period of time. The exercise intervention was performed as a supervised HIIT workout, starting with a 10 mins warm up period, followed by 4 x 4 mins of exercise at 85–95% of the maximum heart rate with each 4 mins period interrupted by 3 mins of exercise at 70% of the maximum heart rate. Although no clear benefits of the HIIT on disease activity and pain were demonstrated, fatigue improved significantly and there was no decline in most of the outcome variables from baseline to 9 months, suggesting that physical activity (even high intensity) is safe.
3. Resistance exercise
Roger-Silva et al. recently evaluated the efficacy of a resistance exercise program involving patients with PsA. This is the first study to carry out a program of resistance exercises in patients with PsA. The participants performed resistance exercises for the upper extremities, lower extremities and trunk. It was used a leg extension machine for the training on the lower extremities. For upper extremities, they used a pulley triceps machine and front pull in addition to free weights (dumbbells). The exercises were divided in three sets of 12 repetitions for each muscle group and were performed twice a week for 12 weeks. The intensity of the exercises was 60% of one maximum repetition and the rest interval between exercises was 1–2 min. The study showed that resistance exercises are effective in improving functional capacity, axial disease activity and the general quality of life, with an additional beneficial effect on pain. However, these improvements were not coupled to significant changes in muscle strength.
Hydrotherapy may be used for PsA patients. Benefits have been reported for physical function, energy, sleep, cognitive function, ability to work and participation in the activities of daily living.
A 50% increase in cardiac output (the amount of blood the heart pumps through the circulatory system in a minute) has been found at a water temperature of 35˚C. This may be the most favorable temperature for hydrotherapy for patients with PsA. An earlier study of hydrotherapy for patients with rheumatoid arthritis has shown that the energy level can be maintained three months after the end of hydrotherapy treatment. Regarding muscle strength, another study showed that positive effects of hydrotherapy may last for about two months. Flexibility was maintained in one study at a three month follow up. It appears that this group of patients benefit from continuous training.
1. Fabio Massimo Perrotta, Silvia Scriffignano, Devis Benfaremo, Mario Ronga, Michele Maria Luchetti, Ennio Lubrano. 2021. New Insights in Physical Therapy and Rehabilitation in Psoriatic Arthritis: A Review. Rheumatol Ther 8(2): 639-649.
2. Ruth S Thomsen, Tom IL Nilsen, Glenn Haugeberg, Anja Bye, Arthur Kavanaugh, Mari Hoff. 2019. The Impact of High Intensity Interval Training on Disease Activity and Patient Disease Perception in Patients with Psoriatic Arthritis: A Randomized Controlled Trial. Arthritis Care & Research 71(4): 530-7.
3. Diego Roger-Silva, Jamil Natour, Emilia Moreira, Fabio Jennings. 2017. A Resistance Exercise Program Improves Functional Capacity of Patients With Psoriatic Arthritis: A Randomized Controlled Trial. Clinical Rheumatology 37(2): 389-395.
4. Maria H. Lindqvist, Gunvor E. Gard. 2013. Hydrotherapy Treatment for Patients with Psoriatic Arthritis—A Qualitative Study. Open J TherRehabil 1:22-30.