How To Manage A Painful Joint

Pain in a joint can be the result of a variety of conditions which may involve inflammatory changes, joint infection, traumatic events, laying down of crystals in the joint and arthritic degeneration. Establishing a diagnosis is the job of the clinician who uses the joint examination and the history of the condition to make an initial diagnosis. Once this is done then laboratory investigations may be done to help confirm the initial impression but they are less useful when just looking for a cause. In the initial phase the clinician is concentrating on determining the likely source of the joint pain and then in finding a pathology.

Joint pain may be coming from within the joint itself, from the anatomical structures around the joint or it can be referred from a remote source. Joint sources of pain include the capsule which surrounds the joint, the periosteal membrane, the synovial membrane lining the capsule, the ligaments and bone under the cartilage, while the joint cartilage itself is insensitive as it possesses no pain nerve endings. Establishing the anatomical structure which is painful is very important as it feeds through to both the diagnosis and treatment of the condition.

Joint disease involves a number of damaging processes which can include enthesitis (inflammation of the junctions between tendons, ligaments and bone), infections, deposition of crystals, joint abnormalities and synovial inflammation. There may be structural abnormalities in a joint or changes secondary to mechanical stresses, such as meniscal tears. Some of the typical processes above may occur in the same joint at the same time. Inflammation of the joint lining (known as synovitis) in rheumatoid arthritis and many other conditions presents as the primary problem. An inflamed, puffy, warm joint results from growth of the membrane which can destroy cartilage.

Where tendons and ligaments insert for fixation into the bone is known as an enthesis and some arthritic conditions are particularly affected in this area. The local soft tissues of the entheses react to the inflammation by forming bony tissue within them which can grow into bony outgrowths along the structures concerned. A painful and inflamed joint can result from crystal deposition along the ligaments, on the synovial membrane or on the surface of the articular cartilage itself. Depending on the deposition pattern the joint can exhibit general or local symptoms and the warmth, exquisite pain and redness of a gouty joint are easily spotted.

Fungi, viruses or bacteria may cause a joint infection, with infections usually resulting from the organism being carried in the blood. Typically part of a more widespread infection, the patient may also feel unwell. The synovium is where the infections occur and there is some local tissue death and increased formation of scar and healing tissues. Toxins may be released by bacteria and these can destroy joint cartilage very quickly. In joint abnormalities the most common pathological process in joints across the world is osteoarthritis and both external and internal factors affect the severity and incidence of this.

Local, more specific factors which can predispose to osteoarthritis are any previous damage to the joint, such as in sports injuries, developmental abnormalities of the joint, abnormalities of cartilage and collagen disorders such as hypermobility. Factors to do with the person include their genetic heritage, their occupation and their bodyweight, although osteoarthritis is most strongly correlated with advancing age. Articular cartilage damage in osteoarthritis is followed by an increase in density of the underlying bone and the formation of bony outgrowths at the joint margins. There may be a synovitis but inflammation is not always involved in this condition.

In examining a joint the initial investigation is targeted at finding out whether the joint is painful or whether a nearby structure such as a muscle, tendon or ligament is responsible or if it is a referred pain from a more distant structure. This is harder to determine in the more central joints such as the shoulder and the hip. Pain around the hip could be from hip osteoarthritis but could also be referred lumbar degenerative disc disease, lumbar stenosis or bursitis over the greater trochanter.