From the Guidelines
Segmental dysfunctions of the spine can contribute to spinal degeneration over time, but they are not the sole cause, as evidenced by the complex interplay of factors including genetics, aging, and lifestyle factors 1. When considering the relationship between segmental dysfunctions and spinal degeneration, it's essential to recognize that these dysfunctions can create altered biomechanical stress patterns that may accelerate degenerative processes.
- Abnormal movement or positioning between vertebral segments can lead to uneven loading of joints, discs, and surrounding tissues.
- This abnormal loading pattern may trigger inflammatory responses and tissue adaptation, including disc thinning, facet joint arthrosis, and osteophyte formation.
- The goal of imaging, as outlined in the ACR Appropriateness Criteria for low back pain, is to identify potential actionable pain generators that could be targeted for intervention or surgery, which may include addressing segmental dysfunctions 1. However, spinal degeneration is multifactorial, and the relationship between dysfunction and degeneration appears to be bidirectional - dysfunction can accelerate degeneration, while degenerative changes can further compromise normal segment function.
- Early identification and appropriate management of segmental dysfunctions through manual therapy, exercise, and lifestyle modifications may help minimize their contribution to degenerative processes, though complete prevention of age-related changes is not possible.
- MRI of the lumbar spine, as recommended in the ACR Appropriateness Criteria, can help identify potential actionable pain generators, including disc degeneration and neural structure abnormalities, which can inform treatment decisions 1.
From the Research
Segmental Dysfunctions and Degeneration
- Segmental dysfunctions of the spine can contribute to degeneration, as evidenced by studies on adjacent segment degeneration (ASD) after spinal fusion 2, 3, 4, 5.
- The incidence of ASD varies depending on the type of fusion and the level of the spine affected, with some studies suggesting that floating fusions of single low lumbar segments are more likely to result in ASD 2.
- The use of interspinous process devices (IPDs) has been shown to reduce the incidence of ASD compared to traditional fusion techniques 3.
- Dynamic or hybrid stabilization devices, such as the Flex+TM system, have also been used to manage ASD and have shown promising results in terms of reducing the incidence of ASD and improving clinical outcomes 4, 5.
Paraspinal Muscle Atrophy and Degeneration
- Paraspinal muscle atrophy has been linked to degenerative lumbar spondylolisthesis (DLS), with studies suggesting that progressive degeneration of segmental stabilizers, including the paraspinal muscles, contributes to a vicious cycle of increasing slippage 6.
- The relationship between paraspinal muscle status and severity of slippage in DLS has been investigated, with findings suggesting that higher degeneration of the erector spinae and multifidus muscles correlates with a higher degree of slippage, while the opposite is found for the psoas muscle 6.
Clinical Implications
- The management of segmental dysfunctions and degeneration requires a comprehensive approach, taking into account the type of fusion, level of the spine affected, and patient-specific factors such as paraspinal muscle status 2, 3, 4, 5, 6.
- The use of IPDs and dynamic or hybrid stabilization devices may be beneficial in reducing the incidence of ASD and improving clinical outcomes in patients with segmental dysfunctions and degeneration 3, 4, 5.
- Further research is needed to fully understand the relationship between paraspinal muscle atrophy and degeneration, and to develop effective strategies for managing DLS and other degenerative spinal conditions 6.