What Causes Facet Joint Hypomobility?
Facet joint hypomobility is caused by slow degeneration or poor motion of the facet joints:
- locked facet joint
- facet joint arthritis
- degenerative facet joint osteophytes (bone spurs)
- joint capsule scarring, thickening or shortening
- protective muscle spasm
What Causes Facet Joint Hypermobility?
Hypermobility is usually caused by trauma:
- overstretched ligaments
- a disease that destroys the joints (e.g. rheumatoid arthritis)
What Causes a Locked Facet Joint?
A locked facet joint is when movement away from the pain is severely limited. When a locked facet joint becomes acute, muscle spasm will attempt to protect it. This results in pain, which may initially be felt in a very small area, worsening as the muscles become fatigued. As the body compensates for locked joints by moving neighbouring joints more than they usually would, pain is often experienced on the opposite side of the locked facet joint and may lead to other conditions. Decreased movement and difficulty stretching are also symptoms.
Locked facet joints are caused by twisting, awkward or unexpected movements. In most cases, facet joint motion exceeds muscle control.
People who repeatedly have locked facet joints typically have weak stability muscles that fail to control spine movement adequately.