Temporomandibular Joint Disorder
The temporomandibular joints are those that connect the lower jaw to the skull and are composed of bone, muscle and joint structures. There are two matching joints, one on each side of the head, located just in front of the ears. These joints are some of the most frequently used joints in the body, put to use when we talk, chew, yawn, swallow and sneeze.
Temporomandibular joint disorder is an alteration of the structures that compose the temporomandibular joints. The disorder occurs when these joints, or muscles and ligaments that support them, are injured, causing dysfunction and pain. It is widely regarded as the second most common cause of facial pain, after toothache. Studies reflect a higher incidence of the disease in younger adults, especially in women aged 20-40 years of age.
Symptoms of temporomandibular joint disorder include bruxism (the tightening or grinding of the teeth), loose or fragile teeth perception, discomfort while chewing or a dry, hot, or scalded mouth. Joint noises or snaps are frequently experienced, with accompanying jaw muscle pain, limitation in the mouth’s openness, jaw displacement while opening the mouth and dislocations and locks while opening and closing the mouth. Secondary to the pain in the joint, the disorder can cause front area headaches, false migraines and nasal obstructions.
Temporomandibular joint disorder is regarded as a ‘multifactor syndrome’, meaning that is it has a number of contributory factors that might have caused the condition. Some of these include a genetic predisposition, a habit of grinding the teeth, trauma to the joint or jaw clenching associated with anxiety.
Intra-Articular Injections
Intra-articular steroid injections are a prescribed line of treatment for relief from joint-pain. Intra-articular injections with local anesthetics or corticosteroids can also be used for the treatment of inflammation in the joint.
Procedure
There are various types of steroids that can be used with intra-articular injections, which have a different duration of effect and action. The guiding principle which determines the effectiveness of each of these preparations is their solubility.
The insoluble preparations are known to have a longer duration of effect and are the most preferred. Aristospan is the most soluble and preferred preparation for intra-articular injections and its duration of effect is usually six months. Aristocort is also highly insoluble, and is usually second choice to Aristopan. This particular preparation normally has a duration of three months. Finally, Depo-Medrol is a highly soluble steroid that should only be used as a last resort. It only lasts for five weeks.
Before the procedure, the appropriate steroid is selected after careful consideration of the patient’s pain history. A local anaesthetic (lidocaine 1%) is administered and the steroid is then injected into the joint. Once completed, an iodinated contrast is injected to observe immediate distribution of the steroid and local anaesthetic and confirm which joints are being treated.
Specialists dealing with intra-articular steroid injections generally instruct their patients to maintain a simple diary of pain for at least a week’s duration after the injection. The commonly recommended entry in the diary is pain vs. previously expected pain or same physical workload.
Outcomes
The intra-articular steroid injections are administered with the aim of providing two to six weeks of pain relief. However, the higher-dose steroids, with or without joint lavage, can provide pain relief for a period as long as 24 weeks.
