Postoperative dysesthesia after PVCR without anterior support applied in Yang's type A severe spinal kyphoscoliosis

Backgrounds

The incidence and characteristics of postoperative dysesthesia (POD) have not been reported for posterior vertebral column resection (PVCR) in the treatment of severe spinal kyphoscoliosis.

Objective

The objective of the study is to investigate the incidence and characteristics of POD in PVCR without anterior support applied in Yang's type A severe spinal kyphoscoliosis.

Material and methods

From August 2010 to December 2019, 167 patients diagnosed with Yang's type A severe spinal kyphoscoliosis who underwent PVCR without anterior support applied were retrospectively reviewed. All the patients were monitored using five modes of intraoperative multimodal neurophysiological monitoring. Neuromonitoring data, radiographic parameters, and neurological complications were reviewed and analyzed. The incidence and characteristics of POD were further summarized. POD was defined as dysesthetic pain or burning dysesthesia which could be caused by spinal cord kinking or dorsal root ganglion (DRG) injury but with no motor deficits.

Results

PVCR without anterior support was successfully conducted in all 167 patients. Intraoperative monitoring events occurred in five patients. One out of these five patients showed postoperative spinal cord injury (Frankel level C) but completely recovered within 9 months postoperation (Frankel level E). The number of levels and osteotomy space for vertebra resection were 1.28 and 3.6 cm, respectively. POD was confirmed in three patients (3/167, 1.8%), characterized as kyphosis with the apex vertebrae in T12 with the kyphotic Cobb angles of 100°, 115°, and 122°, respectively. The osteotomy space of vertebra resection in these three patients were 3.9, 3.8, and 4.2 cm, respectively. After the treatment by drug administration, they reported pain relief for 12-36 days. The pain gradually moved to the distal end of a proper DRG innervated region near the end.

Conclusions

In this study, the incidence rate of POD in Yang's type A severe spinal kyphoscoliosis patients who underwent PVCR without anterior support applied was 1.8% (3/167). Evoked potential monitoring could not detect the occurrence of POD. POD in Yang's type A severe spinal kyphoscoliosis after PVCR could be ascribed to spinal cord kinking and DRG injury.

Is There a Correlation Between Cobb Angle and Pulmonary Function Tests at 2-year Follow-up in Patients With Severe Spinal Deformity Treated by Posterior Vertebral Column Resection?

STUDY DESIGN

A retrospective study.

OBJECTIVE

The aim was to evaluate the relationships of Cobb angle and pulmonary function tests (PFTs) changes in severe spinal deformity and underwent posterior vertebral column resection (PVCR).

SUMMARY OF BACKGROUND DATA

No previous study focused on the correlation of deformity correction and PFTs changes in patients with cobb angle >90 degrees.

METHODS

PFTs values [forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and percent-predicted values FVC%, FEV1%] were evaluated preoperative and at 2 years after PVCR. FVC% <80% were defined as restrictive ventilation dysfunction (RVD), the severity of RVD were divided into mild (FEV1% ≥70%), moderate (70% > FEV1% ≥50%) and severe (FEV1% <50%). The relationships among PFTs values improvements and all possible impact factors (mainly correction cobb angle) collected in this study were analyzed. PFTs data were compared among the 3 RVD subgroups (mild vs. moderate vs. severe) and between residual >30 versus <30 degrees.

RESULTS

A total of 53 cases (28 male/25 female, mean ages 18.9 Y) underwent PVCR in one center from 2004 to 2016 were enrolled cobb angle. When 2 years after PVCR, average PFTs values showed significant improvements. PFTs values changes showed no correlation with correction rate and correction angle. The only significant impact factor in this study for FVC, FVC%, FEV1 improvements was preoperative FVC% and the only impact factor for FEV1% improvement was preoperative FEV1%, the relationships were negative. In accordance with the regression analysis, PFTs values improvements among the 3 RVD subgroups from high to low was severe>moderate>mild. However, patients with residual cobb angle <30 degrees had less PFTs values improvements than patients with residual cobb angle >30 degrees.

CONCLUSIONS

Two years after PVCR, PFTs values were significantly improved. There is no linear correlation between cobb angle change and PFTs values improvements. Lower preoperative FVC% and FEV1% indicate more PFTs values improvements at 2 years post-PVCR.

LEVEL OF EVIDENCE

Level III.

Comparison of Posterior Unilateral Vertebral Column Resection Versus Posterior Vertebral Column Resection for Severe Thoracolumbar Angular Kyphosis as a Revision Surgical Modality: A Retrospective Cohort Study

OBJECTIVE

The objective of this study was to determine the safety and efficacy of posterior unilateral vertebral column resection (PUVCR) as revision surgery for severe thoracolumbar angular kyphosis.

PATIENTS AND METHODS

This is a retrospective cohort study. Adult patients undergoing revision surgery for severe thoracolumbar angular kyphosis in 2010-2016 with ≥2-year follow-up at our institution were assessed. Perioperative complications and clinical outcomes, including blood loss, operation time, Visual Analog Scale score, Oswestry Disability Index, and preoperative and postoperative kyphotic angles, were analyzed.

RESULTS

This study included 58 patients who were divided into the PUVCR group and the posterior vertebral column resection (PVCR) group. Age ( P =0.810), sex distribution ( P =0.500), and vertebrae that underwent surgery ( P =0.638) were similar in the 2 groups. Shorter mean operation time was observed in the PUVCR group as compared with the PVCR group ( P <0.001). In addition, less blood loss was recorded in the PUVCR group as compared with the PVCR group ( P =0.001). There were no significant differences between the 2 groups in a change of Visual Analog Scale scores postoperation versus preoperation ( P =0.961), and at postoperative 3 months ( P =0.906), 12 months ( P =0.752), and 24 months ( P =0.811) versus postoperation, respectively. There were no significant differences between the 2 groups in Oswestry Disability Index changes postoperation versus preoperation ( P =0.157), and at postoperative 3 months ( P =0.899), 12 months ( P =0.947), and 24 months ( P =0.811) versus postoperation, respectively. PUVCR and PVCR were comparable in deformity correction ( P =0.434) and final angle correction ( P =0.790). Complication rates in the PUVCR and PVCR groups were 7.1% and 36.7%, respectively.

CONCLUSION

PUVCR has comparable safety and efficacy to PVCR in treating severe thoracolumbar angular kyphosis, with the advantages of the shorter operation time, less blood loss, and fewer complications.

A preliminary study of spinal cord blood flow during PVCR with spinal column shortening: A prospective clinic study in severe rigid scoliokyphosis patients

Posterior vertebral column resection (PVCR) was the most powerful technique for treating severe rigid spinal deformity, but it has been plagued with high neurologic deficits risk. The fluctuations of spinal cord blood flow (SCBF) play an important role in secondary spinal cord injury during deformity correction surgery.The objective of this study was to first provide the characteristic of SCBF during PVCR with spinal column shortening in severe rigid spinal deformity.Severe rigid scoliokyphosis patients received PVCR above L1 level were included in this prospective study. Patients with simple kyphosis, intraspinal pathology and any degree of neurologic deficits were excluded. The deformity correction was based on spinal column shortening over the resected gap during PVCR. Laser Doppler flowmetry was used to monitor the SCBF at different surgical stages.There were 12 severe rigid scoliokyphosis patients in the study. The baseline SCBF was 316 ± 86 perfusion unite (PU), and the SCBF decreased to 228 ± 68 PU after VCR (P = .008). The SCBF increased to 296 ± 102 PU after the middle shortening and correction which has a 121% increased comparison to the SCBF after VCR (P = .02). The SCBF will slightly decrease to 271 ± 65 PU at final fixation. The postoperative neural physical examination of all patients was negative, and the MEP and SSEP of all patients did not reach the alarm value during surgery.These results indicate that PVCR is accompanied by a change in SCBF, a proper spinal cord shortening can protect the SCBF and can prevent a secondary spinal cord injury during the surgery.

Surgical and radiological outcomes after posterior vertebral column resection according to the surgeon's experience

The purpose of this study was to estimate and analyze the radiological, surgical, and clinical results of posterior vertebral column resection (PVCR) according to the surgeon's experience. Although PVCR has been recognized as the most powerful surgical technique to correct severe spinal deformity, PVCR is a technically demanding procedure with a high complication rate. A retrospective review of the chart and radiographic data of 34 consecutive patients who received PVCR was carried out. According to the time period, the former and latter 17 patients were divided into group 1 and group 2, respectively. Patients' demographics, surgical, radiological/clinical outcomes, and complications were compared between the groups. The demographic data of the patients had no significant difference between the groups. The surgical time (492.5 ± 164.8 vs 350.5 ± 133.9 minutes, P = .010), estimated blood loss (1294.1 ± 711.9 vs 974.1 ± 905.9 mL, P = .045), and length of hospital stay (22.8 ± 12.9 vs 13.4 ± 3.9 days, P = .017) were significantly reduced in group 2. The correction of the PVCR site (40.5° ± 13.3° vs 41.2° ± 23.7°, P = .909), sagittal vertical axis (SVA, 81.9 ± 7.2 mm vs 77.9 ± 102.0 mm, P = .904) were not different between the groups. The total number of complications (22 vs 10, P = .031) and patients having complications (13 vs 7, P = .039) were lower in group 2. Additional surgery was significantly lower in group 2 (13 vs 3, P = .007). The clinical outcomes by revised Scoliosis Research Society-22 (SRS-22r) questionnaire were not different between the groups. Our series revealed that the complications after PVCR may reduce from 17 cases and surgical outcomes might be stabilized by 29 cases.

Results of Posterior Vertebral Column Resection: Surgical Modification of Suk Technique

STUDY DESIGN

Consecutive, retrospective review.

OBJECTIVES

To evaluate and report a modified posterior vertebral column technique.

METHODS

We present a retrospective analysis of 20 patients. Patients having severe 3-dimensional deformity with flexibility less than 20% and managed by posterior vertebral body resection (PVCR) between 2011 and 2014 were included in this study. There were 12 female and 8 male patients, with a mean age of 18 year (range = 3-63 years).

RESULTS

The average follow-up was 3.5 years (2-5 years). The preoperative coronal plane deformity was 84° (70° to 120°) and corrected to 42° (28° to 68°), showing 60% scoliosis correction. Average preoperative local kyphotic angle was 92° (82° to 110°). Correction rate for kyphosis was 62%. All patients after surgery showed their baseline neurological status, and no complications were encountered. The mean estimated blood loss was 1072 mL (350-2000 mL). Thirty-nine percent (33% to 50%) of total blood loss occurred after vertebral body resection, and 61% (50% to 67%) blood loss occurred after the removal of posterior elements. The ratio of estimated blood loss to estimated body blood volume was 26% (range = 19% to 52%).

CONCLUSION

We found that 60% of total bleeding occurs during and after posterior bone resection. Spinal cord is open to possible iatrogenic direct spinal cord injury with surgical instruments for a much shorter period of time compared with the original technique.

Fractional curve progression with maintenance of fusion mass in congenital scoliosis: An 18-year follow-up of a case report

RATIONALE

The management of congenital scoliosis concentrates on early diagnosis and proper surgical treatment before the development of severe deformities. Decision making regarding the appropriate fusion levels, proper surgical treatment, and reduction amount of kyphoscoliosis is very important but difficult in the treatment of congenital scoliosis, especially in young children.

PATIENT CONCERNS

We report an 11-year follow-up of revision surgery for fractional curve progression after combined anterior and posterior fusion without hemivertebra resection using pedicle screw fixation (PSF) in congenital kyphoscoliosis at age 4 years (a total 18-year follow-up). A T12 hemivertebra was documented in a 4-year-old girl and was treated by combined anterior and posterior fusion in two stages with PSF. The fusion mass was maintained but the distal compensatory curve progressed during the follow-up period. The patient underwent a posterior vertebral column resection (PVCR) with extended posterior fusion at the age of 11, 7 years after initial surgery.

OUTCOMES

Eleven years after the revision surgery with PVCR, the patient showed satisfactory results and her spine was well balanced.

LESSONS

The cause of revision surgery for the curve progression may include inappropriate fusion level, incomplete hemivertebra resection, or failure of anterior and posterior fusion. Especially, inappropriate fusion level may result in deterioration of the compensatory curve even without progression of the fusion mass.

CONCLUSION

Appropriate selection of fusion levels, complete resection of hemivertebra, and satisfactory reduction of scoliosis and kyphosis are important factors for deformity correction and prevention of progression of both main and compensatory curves (adding-on of structural curve or progression of compensatory curve) as well as reducing the influence of adjacent vertebral growth using as short a fusion as possible.

Posterior-only vertebral column resection for revision surgery in post-laminectomy rotokyphoscoliosis associated with late-onset paraplegia: A case report and literature review

RATIONALE

Severe post-laminectomy spinal deformity associated with late-onset paraplegia is a complex and rare disorder. Little is known about revision surgery in post-laminectomy rotokyphoscoliosis associated with late-onset paraplegia treated by the single stage posterior-only vertebral column resection (VCR) procedure.

PATIENT CONCERNS AND DIAGNOSES

The patient was a 14-year-old male diagnosed as post-laminectomy rotokyphoscoliosis associated with late-onset paraplegia. He underwent posterior total laminectomy through the thoracic spine for intramedullary spinal cord tumors at the age of 3 years in another hospital. He then developed kyphosis deformity 1 year after laminectomy, and underwent posterior spinal fusion without instrumentation at 9 years of age. However, the deformity gradually progressed over the years. Seven months before admission to our hospital, he developed a significant progression of neurological deficits, including weakness of strength and sensation in lower extremities bilaterally, with no bladder or bowel dysfunction. There was no improvement of spinal cord function with conservative measures, and he required a wheelchair for movement.

INTERVENTIONS

The patient underwent posterior-only VCR by single stage with the purposes of spinal cord decompression and spinal deformity correction.

OUTCOMES

Postoperatively, he was transferred to the intensive care unit (ICU) and required positive pressure ventilation support to improve his respiratory condition. The child experienced cerebrospinal fluid leak (CSF) which resulted in an unplanned return to the operating room. The neurological function improved from preoperative Frankel C to Frankel D within 12 months of surgery, and recovered completely to Frankel E by 18 months. At the 24 month follow-up, the good neurological function was maintained; pulmonary function tests (PFTs) revealed improved forced vital capacity (FVC) and forced expiratory volume for 1 second (FEV1). The patient's coronal major curve and sagittal kyphosis were corrected from 70° to 21°, and 170° to 75°, respectively.

LESSONS

These findings demonstrated that single-stage posterior-only VCR is efficacious but challenging for revision surgery in post-laminectomy rotokyphoscoliosis associated with late-onset paraplegia.

Revision surgery for curve progression after implant removal following posterior fusion only at a young age in the treatment of congenital scoliosis: A case report

RATIONALE

Congenital scoliosis due to a hemivertebra creates a wedge-shaped deformity, which progresses and causes severe spinal deformities as an individual grows. The treatment of congenital scoliosis focuses on early diagnosis and appropriate surgical management before the development of severe deformity.

PATIENT CONCERNS

We report the case of a 4-year-old male child with a left thoracolumbar scoliosis of 27° (T10-T12) due to a T11 hemivertebra who was treated by posterior fusion and pedicle screw fixation at the age of 4 years. The implant was removed due to pain secondary to implant prominence after 4 years without definitive revision surgery, which led to significant progression of the scoliosis, to 50°. The indication for posterior vertebral column resection (PVCR) is a congenital spinal deformity with a curve magnitude greater than 30° with fast progression. This includes documented progression of the curve by more than 5° in a 6- month period, failure of conservative treatment, or both.

OUTCOMES

The patient underwent PVCR of the T11 hemivertebra. Nine years after the revision surgery with PVCR, the patient showed satisfactory results and his spine was well balanced.

LESSONS

This case shows that removal of an implant that was not the only cause of curve progression at a young age may lead to progression of scoliosis and, therefore, should be avoided unless it is absolutely necessary.

CONCLUSION

Congenital scoliosis due to a hemivertebra at a young age could be treated by hemivertebra resection or anterior and posterior epiphysiodesis as definitive surgical treatment. The patient was eventually treated with PVCR, which achieved satisfactory correction without curve progression in a long-term follow-up.