Osteoarthritis represents a significant physical change within joints. This does not naturally reverse, so it is generally regarded as permanent, and progressive. Treatment is generally aimed at reducing pain, improving function and delaying progression.
Drug therapy can involve anti-inflammatory agents to reduce inflammation at the joint site, reducing pain and helping prevent further damage from any inflammatory process. These can be both steroids, and ‘non-steroidal anti-inflammatory drugs’ (NSAIDs). Drugs may also act on transmission of pain in nerves, and on the way pain is processed in the brain. Where the disease is associated with a systemic inflammatory condition, ‘disease-modifying anti-rheumatic drugs’ (DMARDs) may also be used to good effect in preventing disease progression.
Physical treatments may also be of some benefit, and the use of aids such as crutches will reduce loading. The most important physical approach is weight loss.
There is evidence that peripheral and central nervous system changes develop as a part of osteoarthritic pain, and these can make treatment more challenging. Some individuals appear prone to pain sensitisation, and rather than having pain directly in proportion to their OA, they can become sensitised early on in the development of OA leading to a heightened sensation of pain that is not explained by the degree of OA present (Neogi et al., 2015). Multidisciplinary therapy including drugs, physical therapy and psychotherapy can be of significant benefit in these cases.
Activity is in most cases not harmful, and has been shown to reduce pain and slow disease progression. It is important to distinguish between light beneficial activity and heavy repetitive activity that increases the risk of disease progression.
Surgery to cut either the acetabulum or femur (osteotomy) and adjust the joint angle can relieve pain and produce a fully functional joint capable of withstanding full service in the military, police or firefighting.
End-stage OA is often now treated with joint replacement surgery and this is in most cases very successful in eliminating pain and improving mobility. It does not always lead to a return to full activity including sport and heavy manual handling. The degree of pain in joints that have substantial OA changes can vary significantly between individuals; some are able to continue with most physical activities including walking, lifting and carrying significant weights, doing DIY and even continuing to participate in sport with Grade 3 or 4 changes, while others become substantially disabled at Grade 1 or 2.
Total hip replacement involves significant destruction of the proximal femur, with risks associated with high stresses around the shaft of the femoral component and resultant weakening. Resurfacing allows bone-sparing around the proximal femur, with the possibility of a subsequent total hip arthroplasty if and when failure of the resurfaced hip requires it.
The choice of surgical approach would be expected to have some impact on return to sport following total hip arthroplasty. The anterolateral and direct lateral approaches require partial detachment of the abductors from the greater trochanter which may result in temporary or permanent postoperative abductor weakness, but have a low rate of postoperative dislocations. The posterior approach has a risk of dislocation of between 4 and 6% although following capsular repair this can be reduced to 1%.
A comparison of surgical approaches in 3881 cases from the England and Wales national databases found no significant differences in revision risk or revision for dislocation, but a significantly higher improvement in function associated with the posterior approach (Jameson et al., 2014). Catastrophic failure of components has been lowered with development of new alloys and advances in polyethelene preparation and sterilisation. Studies have shown a greater risk of failure of cemented acetabular components in younger more active individuals and further improvements are expected with biologically active metals. There remains concern over metal on metal bearings producing intra-articular debris. Catastrophic failure of ceramic bearings with high impact loading is a concern although ceramic bearings have low wear rates. Hip resurfacing carries fewer risks from athletic participation. (Golant et al., 2010).
GOLANT, A., CHRISTOFOROU, D. C., SLOVER, J. D. & ZUCKERMAN, J. D. 2010. Athletic participation after hip and knee arthroplasty. Bull NYU Hosp Jt Dis, 68, 76-83.
JAMESON, S. S., MASON, J., BAKER, P., GREGG, P. J., MCMURTRY, I. A., DEEHAN, D. J. & REED, M. R. 2014. A comparison of surgical approaches for primary hip arthroplasty: a cohort study of patient reported outcome measures (PROMs) and early revision using linked national databases. J Arthroplasty, 29, 1248-1255.e1.
NEOGI, T., FREY-LAW, L., SCHOLZ, J., NIU, J., ARENDT-NIELSEN, L., WOOLF, C., NEVITT, M., BRADLEY, L. & FELSON, D. T. 2015. Sensitivity and sensitisation in relation to pain severity in knee osteoarthritis: trait or state? Ann Rheum Dis, 74, 682-8.