Step to it

Movement is key to managing arthritis, so current restrictions call for out-of-the-box thinking, explains Dr Liz Barr MRCVS

- Dr Liz Barr MRCVS

AFTER a winter of limited turnout as a result of relentless wet weather, which made fields resemble mud baths, many owners now find themselves with limited opportunity to exercise their horses due to the Covid-19 lockdown. This can cause real difficulty in managing any horse, but particularly one with underlying arthritis.

Arthritis is a disease that causes inflammation and stiffness of the joints. Joints are made up of cartilage – the smooth material that forms the primary weight-bearing surface – and underlying bone. The synovial membrane lines the inside of the joint and produces synovial fluid, a thick substance that lubricates the joint during movement.

The most common type of arthritis is osteoarthritis, where progressive degeneration of the cartilage occurs. This is accompanied by inflammation, with a proliferation of the synovial membrane and changes in bone both around the joint and beneath the cartilage. The synovial fluid becomes thinner and often increases in volume.

Osteoarthritis is caused by a number of factors, including ageing, mechanical overload and genetics, and may result from either abnormal loading of a normal joint or normal loading of an abnormal joint.

Abnormal stresses on a normal joint can be compounded by factors such as obesity, trauma, a defect in the joint surface or altered loading. Abnormal joint physiology may be exacerbated by the ageing, inflammation and fatigue of the components of the joint. Both result in cartilage breakdown, an ineffective repair response and mechanical failure, causing joint destruction and pain.