Facet joint
This article includes a list of general references, but it lacks sufficient corresponding inline citations. (March 2016) |
Facet joint | |
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sagittal section of two lumbar vertebrae and their ligaments | |
Details | |
Identifiers | |
Latin | articulationes zygapophysiales |
MeSH | D021801 |
TA98 | A03.2.06.001 |
TA2 | 1707 |
FMA | 10447 |
Anatomical terminology] |
The facet joints (also zygapophysial joints, zygapophyseal, apophyseal, or Z-joints) are a set of
Innervation
Innervation to the facet joints vary between segments of the spinal, but they are generally innervated by medial branch nerves that come off the dorsal rami. It is thought that these nerves are for primary sensory input, though there is some evidence that they have some motor input local musculature. Within the cervical spine, most joints are innervated by the medial branch nerve (a branch of the
- The facet joint between C2 and C3 is innervated by the third occipital nerve and the C3 medial branch nerve.
- The facet joint between C7 and T1 is innervated by the C7 and C8 medial branch nerves.[citation needed]
In the thoracic and lumbar spine, the facet joints are innervated by the medial branch nerves from the vertebral segment above the upper segment and the upper segment. For example, the facet joint between T1 and T2 is innervated by C8 and T1 medial branch nerves. Facet joint between L1 and L2; the T12 and L1 medial branch nerves. However, the L5 and S1 facet joint is innervated by the L4 medial branch nerve and the L5 dorsal ramus. In this case, there is no L5 medial branch to innervate the facet joint.[citation needed]
Function
The biomechanical function of each pair of facet joints is to guide and limit movement of the spinal motion segment.
The facet joints, both superior and inferior, are aligned in a way to allow flexion and extension, and to limit rotation. This is especially true in the lumbar spine.
Facet joint arthritis
In large part due to the mechanical nature of their function, all joints undergo degenerative changes with the wear and tear of age. This is particularly true for joints in the spine, and the facet joint in particular. This is commonly known as facet joint arthritis or facet arthropathy.[3] As with any arthritis, the joint can become enlarged due to the degenerative process. Even small changes to the facet joint can narrow the intervertebral foramen, possibly impinging on the spinal nerve roots within.[3] More advanced cases can involve severe inflammatory responses in the Z-joint, not unlike a swollen arthritic knee.
Diagnosis
Facet joint arthritis may not always have any symptoms, but often manifests as a dull ache across the back.[4] However like many deep organs of the body it can be experienced by the patient in a variety of referral pain patterns. The location of facet joints, deep in the back and covered with large tracts of paraspinal muscles, further complicate the diagnostic approach. Typically facet joint arthritis is diagnosed with specialized physical examination by specialist physicians such as facet loading (also called Kemps test). However, this test has poor sensitivity (50-70%) [5] and specificity (67.3%) [6] for lumbar facet pain. Often providers perform diagnostic injections to determine if the facet joint is the underlying source of pain.
Treatment
Conservative treatment
Conservative treatment of facet joint arthritis involves
Corticosteroid injections
Corticosteroid injections into the joint space may provide temporary pain relief anywhere from days to several months. With repeated injections, sometimes the patient may experience a more permanent improvement in their symptoms.[7] Steroid injections are typically performed under image guidance to ensure accuracy given the complex shape and deep location of the facet.[8] Some patients do not benefit from corticosteriod injections.[7]
Ablation
Radiofrequency ablation or lesioning, also known as rhizolysis, can be used to give longer lasting relief by destroying the nerves that supply the facet joint (medial branch nerves).[9] Current guidelines as per the International Spine Intervention Society require two successful medial branch blocks before progressing to a radiofrequency ablation.
Surgery
Surgery, in the form of a facetectomy, can be performed in certain cases, particularly when the nerve root is affected.
Etymology
Ancient Greek: zygon ("yoke") + apo ("out/from") + phyein ("grow")
See also
- Articular processes
- Artificial facet replacement
- Facet joint injection
- Facet syndrome
References
- ISBN 978-0-443-06812-6, retrieved 2020-11-03
- ISBN 978-0-7234-3226-5, retrieved 2020-11-03
- ^ PMID 30855816.
- ISBN 978-0-7216-0334-6, retrieved 2020-11-03
- ^ "Relationship of Physical Examination Findings and Self-Reported Symptom Severity and Physical Function in Patients With Degenerative Lumbar Conditions". academic.oup.com. Retrieved 2023-01-26.
- PMID 16906195.
- ^ ISBN 978-1-4160-4836-7, retrieved 2020-11-03
- ^ NASS on facet joint injections
- ^ "Archived copy" (PDF). Archived from the original (PDF) on 2020-04-06. Retrieved 2019-11-13.
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: CS1 maint: archived copy as title (link)
9. Shin-Tsu Chang, Chuan-Ching Liu, Wan-Hua Yang. Single-photon emission computed tomography/computed tomography (hybrid imaging) in the diagnosis of unilateral facet joint arthritis after internal fixation for atlas fracture. HSOA Journal of Medicine: Study & Research 2019; 2: 010.
10. Zhu Wei Lim, Shih-Chuan Tsai, Yi-Ching Lin, Yuan-Yang Cheng, Shin-Tsu Chang. A worthwhile measurement of early vigilance and therapeutic monitor in axial spondyloarthritis: a literature review of quantitative sacroiliac scintigraphy. European Medical Journal (EMJ) Rheumatology 2021 July 15; 8[1]:129-139.