From the Guidelines
A kyphotic deformity greater than 20-25 degrees is generally considered clinically significant in thoracolumbar trauma. This threshold represents the point at which the biomechanical stability of the spine becomes compromised, potentially leading to progressive deformity, chronic pain, and neurological complications 1. The normal thoracolumbar junction has a slight kyphosis of approximately 0-10 degrees, so deviations beyond this range raise concern.
Some key points to consider in the assessment of kyphotic deformity in thoracolumbar trauma include:
- The use of CT scans for initial assessment, as they are preferred to radiographs for detecting significant injury to the thoracolumbar spine 1
- The importance of monitoring for progressive deformity, as some fractures may develop increasing kyphosis over time despite initial stability
- The consideration of other factors that influence treatment decisions, including the patient's neurological status, overall spinal alignment, integrity of the posterior ligamentous complex, and the presence of canal compromise
In terms of specific degree of kyphotic deformity, a range of 20-25 degrees is commonly cited as the threshold for clinical significance. However, it is essential to consider individual patient factors and the overall clinical context when making treatment decisions. The assessment should include both initial and follow-up imaging to monitor for progressive deformity.
From the Research
Significant Kyphotic Deformity in Thoracolumbar Trauma
- The degree of kyphotic deformity considered significant in thoracolumbar trauma can vary, but several studies provide insight into the range of degrees that are typically considered significant.
- A study published in 1996 2 found that the precorrection kyphosis ranged from 30-60 degrees, with a mean of 40 degrees +/- 10.8 degrees, in patients with post-traumatic kyphosis.
- Another study published in 2018 3 reported that the mean kyphosis was 34.21±3.7 degrees at the time of admission and 17.64±3.20 degrees at the time of final follow-up in the operative group, while the mean kyphosis was 32.96±4.06 degrees at the time of admission and 40.28±4.72 degrees at the time of final follow-up in the conservative group.
- A study published in 2010 4 suggested that surgical correction of post-traumatic kyphotic deformity should be considered in patients presenting a local excess of kyphosis in the fractured area superior to 20 degrees with poor functional tolerance.
- A study published in 2006 5 found that the average regional angulation (RA) passed from 43.8 degrees (31 to 55) to 2.2 degrees (-5 to 7) after surgery, and the average effective regional deformity (ERD) was 47.2 degrees (24 to 66) preoperatively and 8.6 degrees (-5 to 37) at follow-up.
- A study published in 2015 6 reported that the mean Cobb angle significantly improved from 39.6° to 5.6° in the modified PSO group and from 39.1° to 4.8° in the standard PSO group, with no significant difference between the two groups preoperatively or at the final follow-up.
Key Findings
- The range of significant kyphotic deformity in thoracolumbar trauma can vary, but degrees above 20-30 degrees are often considered significant 2, 4, 6.
- Surgical correction can improve kyphotic deformity, with average corrections ranging from 25-60 degrees 2, 5, 6.
- The degree of kyphotic deformity can affect functional tolerance and quality of life, with higher degrees of deformity often associated with poorer outcomes 3, 4.