Lumbar Spondylolisthesis
Brief description.
Spondylolisthesis is the most common cause of structural low back pain in children and adults. There are five classifications of spondylolisthesis: developmental (congenital), isthmic fracture (stress fracture), degenerative, traumatic, and pathological. The most common cause of lumbar spondylolisthesis in children or adults is a defect or stress fracture of the lumbar spinal slit. The lumbar spine narrow part is a part of the lumbar vertebral body located between the upper and lower articular processes of the two lumbar vertebrae (Figure 1). A defect in the narrow part can allow the vertebral body to shift or slide anteriorly, which creates a slip (Figure 2).
Slippage often occurs bilaterally and simultaneously, resulting in mechanical instability. Lumbar slippage is usually classified into 5 degrees depending on the degree of slippage; degree I: 0-25% slippage, degree II: 25-50% slippage, degree III: 50-75% slippage, degree IV: 75-100% slippage, and degree V: greater than 100% slippage. About 85%-90% of patients with slippage occur in the lumbar 5 segment. Yang Ting, Department of Orthopedics and Traumatology, Jiangsu Provincial Hospital of Traditional Chinese Medicine
Figure 1
Figure 2
Many people with slippage have no symptoms and are unaware of their current disease status. This is the case in 5-6% of the normal population, but 10-15% of these individuals will gradually develop symptoms.
What causes spondylolisthesis?
Although some specific risk factors have been identified, the exact cause of spondylolisthesis is not known. For example, spondylolisthesis is more common in patients who play sports that require repeated or sustained hyperextension of the lower back. These sports include gymnastics, diving, wrestling, weightlifting, and rugby forward (Figure 3). It has been verified that repetitive injuries lead to narrow weakness and progressive formation of a slip.
Another theory is that genes play an important role in the formation of narrow defects as well as in the process of slippage. Some ethnic groups, such as the Inuit Eskimos, have a very high incidence of lumbar slippage (approximately 40%), suggesting a genetic influence.
How to diagnose lumbar spondylolisthesis
To diagnose lumbar spondylolisthesis is based on symptoms, physical examination, and radiographs of the spine. Ortho-, lateral-, and oblique images of the lumbar spine are essential for the evaluation of spondylolisthesis (Figures 4A and 4B), and bone scans, CT, and MRI scans are also needed to evaluate for spondylolisthesis. Bone scans are primarily used as a means of identifying whether the injury is acute or chronic.
The most common findings on physical examination are low back pain and pain on hyperextension of the lumbar spine (Figure 4), and another is N cord muscle tension. Most patients will not have neurological symptoms or lower extremity involvement pain, but there may be radiating pain due to nerve irritation, which is most often seen in patients with high levels of slippage (degrees III,IV,V).
Figure 4A.
Grade II-III lumbar 5-sacral 1 slippage Figure 4B.
Physical examination of the lumbar spine in hyperextension
How is spondylolisthesis treated?
The first treatment measure for lumbar spondylolisthesis is conservative treatment, which aims to reduce pain and facilitate recovery. Conservative treatment measures include changes in activity patterns (from exercise to rest), brace immobilization (Figure 6), and physical therapy to improve lumbar flexibility and strength. Non-steroidal anti-inflammatory drugs (ibuprofen) are also commonly used to relieve pain and reduce the inflammatory response. It is important to understand that the efficacy of conservative treatment is based on the degree of the patient’s symptoms.
For those with acute pain, anterior flexion bracing and physical therapy need to be continued for 6-12 weeks. If the patient is no longer in pain during conservative treatment, he or she can gradually regain movement and activity that he or she can tolerate by continuing to wear the brace. Patients should be advised to avoid repetitive type hyperextension exercises. Non-surgical treatment is successful in relieving 80-85% of children and adult patients with acute pain.
If the patient has persistent pain symptoms, the conservative treatment measures described above may be continued. Closure in the narrow part of the spine can be one of the treatment measures to relieve pain and inflammation.
Figure 5A.
CT 3D scan reconstruction of L5 isthmus cleft Figure 5B.
MRI scan showing lumbar 5 sacral 1 4th degree slip
If pain persists despite conservative treatment, surgical treatment is recommended. Surgical treatment also includes which are pediatric patients with severe slippage (III degree or greater slippage). Surgery can prevent further slippage of the vertebral body as well as long-term pain. There are many different surgical approaches to treating lumbar spondylolisthesis. Direct repair and/or posterior lumbar fixation and fusion with an implant are frequently used in patients with long-term chronic pain and/or severe slippage.
Figure 7: Boston brace (anteversion brace)
Key points to remember.
- Slippage is a common cause of low back pain in adults and athletes
- N-cord tension often accompanies slippage
- Conventional conservative treatment includes activity modification, rest, use of lumbar brace, physical therapy, pain medication, injections, etc. to relieve pain
- Treatment of lumbar spondylolisthesis is symptom-specific (no pain = no treatment needed {except for those with severe spondylolisthesis})
- If conservative treatment does not improve symptoms, there are several surgical options. The most common surgical options are direct repair of the defect and posterior lumbar fixation with bone graft fusion
Figure 8A: Direct lumbar 5 narrow laceration repair
Figure 8B: Posterior fixed graft fusion of lumbar 4-5