Delayed-onset radiculopathy caused by a retropulsed bone fragment after percutaneous kyphoplasty: report of four cases and literature review

Comparison of Unilateral and Bilateral Robot-Assisted Percutaneous Kyphoplasty in Treating Osteoporotic Vertebral Compression Fracture

OBJECTIVE

To investigate the efficacy and safety of unilateral and bilateral robot-assisted percutaneous kyphoplasty (RAPKP) in treating thoracolumbar osteoporotic vertebral compression fractures.

METHODS

Our study retrospectively analyzed 78 patients (unilateral group: 48, bilateral group: 30) with osteoporotic vertebral compression fracture treated with RAPKP from January 2020 to July 2022. The operation time, X-ray exposure time, bone cement volume, postoperative bone cement distribution, preoperative and postoperative pain visual analog scale (VAS) scores, Oswestry Dysfunction Index (ODI), Cobb angle, vertebral height, bone cement leakage, adjacent vertebral fracture, and postoperative computed tomography (CT) in both groups were recorded.

RESULTS

All patients were successfully treated with RAPKP and followed up for 19.90 ± 5.38 months. Our results showed that the VAS core, ODI, vertebral height, and Cobb angle at postoperative follow-up were significantly improved in both groups compared to the preoperative period (P < 0.05). The operation time in the bilateral group (46.20 ± 6.89 minutes) was not statistically different from the unilateral group (42.54 ± 10.16 minutes) (P > 0.05), while the volume of bone cement injected was significantly more in the bilateral group (5.93 ± 1.81 mL) than in the unilateral group (4.73 ± 0.51 mL) (P < 0.05). In addition, the distribution of bone cement in the bilateral group was significantly better than that in the unilateral group (P < 0.05). There were no significant differences in X-ray exposure dose between the 2 groups (P > 0.05). Bone cement leaked in 9 cases (18.75%) in the unilateral group and 6 cases (20.00%) in the bilateral group (P > 0.05). No neurovascular injury or infection occurred. There were 8 cases (16.67%) of adjacent vertebral fracture in the unilateral group and 4 cases (13.33%) in the bilateral group (P > 0.05). Postoperative CT ratios of adjacent vertebrae (operated vertebra/upper adjacent vertebra: unilateral: 10.65 ± 2.7, bilateral: 11.32 ± 3.1; operated vertebra/lower adjacent vertebra: unilateral: 11.67 ± 3.0, bilateral: 12.48 ± 2.9) (P > 0.05).

CONCLUSIONS

Unilateral or bilateral RAPKP improves patients' VAS, ODI, sagittal index, and Cobb angle. Unilateral RAPKP possesses the advantage of fewer puncture injuries. However, bilateral RAPKP has better postoperative cement distribution, and we believe that bilateral RAPKP has a better long-term prognosis, so we recommend bilateral RAPKP.

Surgical management of lower limb radiculopathy following acute singe-level osteoporotic vertebral fracture of lower lumbar spine in geriatric patient: a retrospective study

BACKGROUND

Radiculopathy of the lower limb after acute osteoporotic vertebral fractures (OVFs) in the lower lumbar spine is uncommon in geriatric patients. Moreover, surgical intervention is generally recommended in patients who are irresponsive to conservative treatment. Determining an optimum surgical strategy is challenging considering the poor general condition of this population. Thus, herein, we established an algorithm for surgically managing this clinical scenario, hoping to provide a reference for making a surgical decision.

METHODS

We retrospectively studied patients who suffered from new-onset radiculopathy of the lower limb after acute single-level OVFs in the lower lumbar spine and eventually underwent surgical intervention at our department. Information on the demographics, bone quality, AO spine classification of the vertebral fracture, pre-existing degenerative changes, including foraminal stenosis and lumbar disc herniation, and surgical intervention type was collected. Additionally, clinical outcomes, including preoperative and postoperative visual analog scale (VAS) scores for back and leg pain, Oswestry disability index (ODI), and MacNab criterion for response to surgery, were evaluated.

RESULTS

From September 2019 to December 2021, a total of 22 patients with a mean age of 68.59 ± 9.74 years were analyzed. The most involved vertebra was L5 (54.5%), followed by L4 (27.3%) and L3 (18.2%). Among the 22 patients, 15 (68.2%) were diagnosed with the A1 type fracture of AO classification, and among them, 11 (73.3%) were characterized by the collapse of the inferior end plate (IEP). Three patients (13.6%) suffered from A2-type fractures, whereas four patients (18.2%) suffered from A3-type fractures. Pre-existing degenerative changes were observed in 12 patients (54.5%) of the patients. A total of 16 patients (72.7%) were treated by percutaneous kyphoplasty (PKP). Additionally, three patients underwent posterior instrumentation and fusion, two patients underwent a secondary endoscopic foraminoplasty, and one patient underwent a secondary radiofrequency ablation. The mean follow-up period was 17.42 ± 9.62 months. The mean VAS scores for leg and back pain and ODI decreased significantly after the surgery (P < 0.05). The total satisfaction rate at the last follow-up was 90.9% per the Macnab criterion.

CONCLUSION

Patients with OVFs in the IEP are predisposed to suffer from radiculopathy of the lower limb. PKP alone or in combination with other minimally invasive surgical strategies is safe and effective in treating stable fractures. Additionally, aggressive surgical intervention should be considered in patients with unstable fractures or severe foraminal encroachment.

Delayed onset of anterior spinal artery syndrome caused by retropulsed bone fragment after kyphoplasty: Case report and literature review

Background

Percutaneous balloon kyphoplasty is a minimally invasive technique to treat refractory symptomatic osteoporotic vertebral compression fractures. A rare complication called anterior spinal artery syndrome has been documented several times in the literature after the procedure from cement embolism; however, the authors report an unusual case of anterior spinal artery syndrome following kyphoplasty through retropulsion of bone fragmentation.

Case presentation

An 83-year-old male was admitted to an acute care hospital for severe low thoracic back pain without neurological symptoms. Computed tomography imaging showed T8 vertebral body compression fracture with 75% height loss. Kyphoplasty was performed four days after the admission without complications. On day nine postoperatively, the patient developed acute onset paraparesis of the lower extremities dissociated sensory deficits involving bilateral loss of temperature and pain, but preserved proprioception and vibratory sense. Magnetic resonance imaging of the spine revealed T2 intramedullary hyperintensity spanning from T7-9 and retropulsion of the bone fragments from a refracture of the T8 vertebral body.

Conclusion

This study highlights a rare complication from a standard pain procedure through an unusual mechanism of injury. Clinicians who suspect acute myelopathy following vertebral augmentation procedures should obtain a computed tomography angiogram to identify a potential occluded vessel. If negative, individuals should proceed to magnetic resonance imaging to rule out retropulsion of bone fragmentation into the spinal cord.