Facet joint disease (or syndrome) is where pain is caused by the facet joints, which are a pair of joints at the posterior aspect of the spine at each vertebral level. They provide support to the spine and allow movement in certain directions depending on which orientation they are aligned, and this is different in each region of the spine. The pain is typically caused by wear and tear – or arthritis – and this may be in isolation or can be the sequelae of degenerative disc disease.
The symptoms that develop from this problem depend on the region of the spine that is affected. In the cervical spine, the pain will typically present in the neck, shoulders or upper back. If there is associated facet joint hypertrophy (enlargement) it can also lead to pressure on the exiting nerve root and this can cause arm pain, weakness and/or numbness. If large enough and occurring in combination with disc prolapse, there may also be cervical spinal stenosis, and this can cause pressure on the spinal cord itself. This may be asymptomatic if mild, or may cause cervical myelopathy (see section on cervical myelopathy).
In the lumbar spine, the pain may present with back pain and or/stiffness, as well as pain in the buttock and legs. Again, the facet joints may become enlarged and they can lead to compression of the exiting nerve root causing pain, numbness and/or weakness of the leg. If the enlargement is severe enough (typically also in combination with degenerative disc disease) this may lead to compression of the whole spinal canal, and the patient will present with symptoms of spinal canal stenosis (see section on spinal canal stenosis).
This can involve a combination of bone scan, CT scan, and MRI scan depending on the presentation. They may all be required or can be used in isolation based on the proposed treatment.
The treatment for this problem is non-operative to begin with. The use of physical therapy, lifestyle modification, analgesic medications and allied health input is first line. Image-guided injections can be used for pain relief as well as diagnosis.
If the injection was helpful but did not provide pain relief for a long period of time, radiofrequency ablation therapy can be offered. This involves burning the nerves beside the facet joint while under sedation to allow for a more prolonged pain relief. Surgery can be offered if all other options have not helped, and this will typically involve fusion +/- decompression.