Modified posterior osteotomy for osteoporotic vertebral collapse with neurological dysfunction in thoracolumbar spine: a preliminary study

Abstract

Objective: The risk of osteoporotic vertebral collapse (OVC) associated with delayed neurological dysfunction (DND) is substantial, and performing surgery for this condition in elderly patients presents challenges. The focus of the current research is on simplifying surgical procedures while maintaining their effectiveness. This study was designed to contribute clinical data supporting the use of modified posterior osteotomy for treating thoracolumbar OVC with DND. The study compares perioperative clinical parameters, imaging data characteristics, and changes in efficacy outcome indicators to provide evidence for the advancement of this technique.

Methods: A total of 12 patients diagnosed with osteoporotic vertebral collapse and neurological dysfunction were included in the study. All patients underwent modified posterior osteotomy. Data regarding perioperative and radiological parameters as well as complications such as surgery duration, blood loss, ASIA grade, VAS, ODI, regional kyphosis angle (RKA), anterior vertebral height ratio (AVHr), and spinal canal clearance ratio (SCCr), were collected retrospectively. These parameters were then analysed to evaluate the clinical efficacy and safety of the modified posterior osteotomy technique.

Results: A total of 12 patients were included in the study, with a mean age of 65.5 ± 9.7 years. The average follow-up period was 29.4 ± 5.0 months. The mean operative blood loss was 483.3 ± 142.0 ml, and the average operative time was 3.7 ± 0.7 h. The visual analogue scale (VAS) score decreased from a preoperative value of 5.8 ± 0.7 to a final follow-up value of 1.3 ± 0.8 (P < 0.05), indicating a significant improvement in pain. The ODI decreased from 65.2 ± 6.0 before surgery to 20.5 ± 7.0, indicating a decrease in disability, and the postoperative neurological function showed a significant improvement. Correction of the RKA was observed, with the angle changing from 35.8 ± 10.8° before surgery to 20.0 ± 3.5° after surgery and to 22.5 ± 3.1° at the final follow-up. Similarly, correction of the AVHr was observed, with the height changing from 39.3 ± 18.0 to 63.0 ± 14.3 after surgery and to 53.9 ± 8.9 at the final follow-up. Correction of the SCCr was also observed, with the ratio changing from 54.9 ± 5.4 to 68.1 ± 5.3 after surgery and to 68.68 ± 6.76 at the final follow-up.

Conclusions: Posterior modified osteotomy is an effective treatment for thoracolumbar osteoporotic fractures with OVC combined with DND. It can significantly preserve vertebral height, increase vertebral canal volume, correct kyphotic angle, and improve postoperative neurological function. The simplified osteotomy also offers advantages in terms of operating time, blood loss, postoperative VAS score, and improvement in lumbar function.

Keywords: Kyphosis; Neurological dysfunction; Osteoporosis vertebral collapse fracture; Osteotomy; Surgical treatment.

Fig. 1

Flowchart of modified osteotomy model. A and B show the osteotomy scope, which includes one lamina, transverse process, inferior articular process of upper vertebral body, and unilateral pedicle of osteotomy vertebral body corresponding to collapsed vertebral body. C Excision of vertebral bone mass protruding into spinal canal. D Drive from the rear to the front column through a special screwdriver. E and F The anterior column and middle column of vertebral body were partially lifted, and the compression in spinal canal and kyphosis was obviously improved

Fig. 2

Imaging measurement [12]. AVHr is defined as the ratio of the anterior vertebral height to the adjacent unfractured anterior vertebral height. The specific calculation method is as follows: the anterior edge height a of the fractured upper vertebral body, the anterior edge height b of the fractured lower vertebral body, the anterior edge height c of the fractured vertebral body, AVHr = 2 * C/a + b * 100. RKA is defined as the angle between the lower endplate of the fractured vertebral body and the lower endplate directly above the vertebral body. SCCr is the spinal canal clearance ratio, calculated as the ratio of the diameter of the vertebral canal at the compression site (y) on the sagittal X-ray to the diameter of the upper vertebral canal (x), SCCr = y/x * 100

Fig. 3

Neurological function scores of patients preoperatively and at final follow-up

Fig. 4

A 72-year-old female patient was admitted for low back pain and weakness in both lower limbs. Physical examination revealed local kyphosis, Franke grade D, and no pathological signs. BMD: − 5.7, VAS: 6 points, ODI: 75. T12 fracture with vertebral collapse, kyphosis deformity, RKA: 35.4°, SCCr: 54.8, AVHr: 25.9 (A, B). 3D CT of the spine showing a wedge-shaped collapse of the T12 with protruding bone blocks entering the spinal canal from the posterior wall (C). MRI of the thoracolumbar region shows significant compression of the spinal cord at T12 (D). Lumbar spine radiographs in both anteroposterior and lateral views. The patient underwent local laminectomy at T12 and spinal internal fixation at T10-L2, with some vertebral bodies reinforced with bone cement. Postoperative 1-week RKA: 21.7°, SCCr: 77.1, AVHr: 58.0 (E, F). Final follow-up, RKA: 25°, SCCr: 66.8, AVHr: 49.3 (K, L)