Peigen Xie

Unilateral pedicle screw fixation through a tubular retractor via the Wiltse approach compared with conventional bilateral pedicle screw fixation for single-segment degenerative lumbar instability: a prospective randomized study

OBJECT Treatment of patients with single-segment degenerative lumbar instability using unilateral pedicle screw fixation can achieve stability and fusion rates similar to those of bilateral pedicle screw fixation. The aim of this study was to analyze the clinical outcome of using unilateral pedicle screw fixation through a tubular retractor via the Wiltse approach to treat single-segment degenerative lumbar instability. METHODS Thirty-nine consecutive patients with single-segment, low-grade, degenerative lumbar instability were randomly assigned to treatment with either unilateral (n = 20) or bilateral (n = 19) pedicle screw fixation. In the unilateral group, patients underwent unilateral posterior lumbar interbody fusion (PLIF) and ipsilateral pedicle screw fixation through a tubular retractor via the Wiltse approach. In the bilateral group, patients underwent modified bilateral PLIF with bilateral pedicle screw fixation via the posterior midline approach. During follow-up, patients were evaluated using a visual analog scale (VAS), the Japanese Orthopaedic Association (JOA) score, and the Oswestry Disability Index. RESULTS The unilateral group had a shorter operative duration (p < 0.05) and less blood loss (p < 0.001). All patients completed more than 2 years of follow-up (mean 36 months). In general, the time trends in improvement on the VAS and JOA differed slightly between the groups through 2 years, but no significant difference in back pain VAS score or leg pain VAS score was found between these 2 groups at the 2-year follow-up. Complete bone fusion was shown on CT in all patients at the 2-year follow-up. CONCLUSIONS Unilateral pedicle screw fixation through a tubular retractor via the Wiltse approach appears to be as safe and effective as bilateral pedicle screw fixation for the treatment of single-segment degenerative lumbar instability.

Comparison of anterior corpectomy and fusion versus laminoplasty for the treatment of cervical ossification of posterior longitudinal ligament: a meta-analysis.

OBJECTIVE The purpose of this study was to compare the effectiveness and safety of anterior corpectomy and fusion (ACF) with laminoplasty for the treatment of patients diagnosed with cervical ossification of the posterior longitudinal ligament (OPLL). METHODS The authors searched electronic databases for relevant studies that compared the use of ACF with laminoplasty for the treatment of patients with OPLL. Data extraction and quality assessment were conducted, and statistical software was used for data analysis. The random effects model was used if there was heterogeneity between studies; otherwise, the fixed effects model was used. RESULTS A total of 10 nonrandomized controlled studies involving 819 patients were included. Postoperative Japanese Orthopaedic Association (JOA) score (p = 0.02, 95% CI 0.30-2.81) was better in the ACF group than in the laminoplasty group. The recovery rate was superior in the ACF group for patients with an occupying ratio of OPLL of ≥ 60% (p < 0.00001, 95% CI 21.27-34.44) and for patients with kyphotic alignment (p < 0.00001, 95% CI 16.49-27.17). Data analysis also showed that the ACF group was associated with a higher incidence of complications (p = 0.02, 95% CI 1.08-2.59) and reoperations (p = 0.002, 95% CI 1.83-14.79), longer operation time (p = 0.01, 95% CI 17.72 -160.75), and more blood loss (p = 0.0004, 95% CI 42.22-148.45). CONCLUSIONS For patients with an occupying ratio ≥ 60% or with kyphotic cervical alignment, ACF appears to be the preferable treatment method. Nevertheless, laminoplasty seems to be effective and safe enough for patients with an occupying ratio < 60% or with adequate cervical lordosis. However, it must be emphasized that a surgical strategy should be made based on the individual patient. Further randomized controlled trials comparing the use of ACF with laminoplasty for the treatment of OPLL should be performed to make a more convincing conclusion.

Percutaneous transforaminal endoscopic discectomy compared with microendoscopic discectomy for lumbar disc herniation: 1-year results of an ongoing randomized controlled trial

OBJECTIVE A prospective randomized controlled study was conducted to clarify whether percutaneous transforaminal endoscopic discectomy (PTED) results in better clinical outcomes and less surgical trauma than microendoscopic discectomy (MED). METHODS In this single-center, open-label, randomized controlled trial, patients were included if they had persistent signs and symptoms of radiculopathy with corresponding imaging-confirmed lumbar disc herniation. Patients were randomly allocated to the PTED or the MED group by computer-generated randomization codes. The primary outcome was the Oswestry Disability Index (ODI) score 1 year after surgery. Secondary outcomes included scores of the Medical Outcomes Study 36-Item Short-Form Health Survey bodily pain and physical function scales, EuroQol Groups EQ-5D , and the visual analog scales for back pain and leg pain. Data including duration of operation, in-bed time, length of hospital stay, surgical cost and total hospital cost, complications, and reoperations were recorded. RESULTS A total of 153 participants were randomly assigned to 2 treatment groups (PTED vs MED), and 89.5% (137 patients) completed 1 year of follow-up. Primary and secondary outcomes did not differ significantly between the treatment groups at each prespecified follow-up point (p > 0.05). For PTED, there was less postoperative improvement in ODI score in the median herniation subgroup at 1 week (p = 0.027), 3 months (p = 0.013), 6 months (p = 0.027), and 1 year (p = 0.028) compared with the paramedian subgroup. For MED, there was significantly less improvement in ODI score at 3 months (p = 0.008), 6 months (p = 0.028), and 1 year (p = 0.028) in the far-lateral herniation subgroup compared with the paramedian subgroup. The total complication rate over the course of 1 year was 13.75% in the PTED group and 16.44% in the MED group (p = 0.642). Five patients (6.25%) in the PTED group and 3 patients (4.11%) in the MED group suffered from residue/recurrence of herniation, for which reoperation was required. CONCLUSIONS Over the 1-year follow-up period, PTED did not show superior clinical outcomes and did not seem to be a safer procedure for patients with lumbar disc herniation compared with MED. PTED had inferior results for median disc herniation, whereas MED did not seem to be the best treatment option for far-lateral disc herniation. Clinical trial registration no.: NCT01997086 (clinicaltrials.gov).

Clinical and Radiographic Results of a Minimally Invasive Lateral Transpsoas Approach for Treatment of Septic Spondylodiscitis of the Thoracolumbar and Lumbar Spine

BACKGROUND The minimally invasive lateral transpsoas approach allows retroperitoneal access for discectomy and graft placement. However, the procedure has rarely been used for the treatment of septic spondylodiscitis. The purposes of this study were to evaluate the clinical and radiographic outcomes from this minimally invasive procedure for septic spondylodiscitis. METHODS Thirty-one consecutive patients (17 males and 14 females) were included in this study from July 2013 to January 2016. Clinical outcomes were assessed by Oswestry Disability Index, visual analog scale, modified Macnab criteria, and inflammatory parameters. Radiographic results were analyzed by studying the changes in diseased disc height, lordosis, and fusion status. RESULTS The Oswestry Disability Index and visual analog scale score improved by 58% and 69% at the last follow-up. The modified Macnab criteria were found to be excellent in 21 patients (68%) and good in 10 (32%). Inflammatory parameters normalized over the average 24 months follow-up. There were no major complications that might have influenced the outcomes in this cohort. A complete fusion after 12 months was achieved in 87% of patients. A mean 7.5 mm restoration in disc height and 6.4° restoration in lumbar lordosis were observed in all patients, whereas an average 4.5 mm loss in restored height resulting from graft subsidence was observed in 24 patients during the follow-up. However, graft subsidence did not influence clinical outcomes significantly. CONCLUSIONS A minimally invasive lateral transpsoas approach in combination with instrumentation provides a novel treatment for patients with septic spondylodiscitis without severe kyphosis and neurologic impairment.

A Comparison of the Anterior Approach and the Posterior Approach in Treating Multilevel Cervical Myelopathy: A Meta-Analysis.

Study Design: A meta-analysis. Objective: To compare the effectiveness and the safety of the anterior approach with those of the posterior approach for patients diagnosed with multilevel cervical myelopathy (MCM). Summary of Background Data: Although many studies had compared the outcomes of the anterior approach with that of the posterior approach for MCM in recent years, choosing a proper surgical approach is still a controversial issue . Methods: We searched electronic databases for relevant studies that compared the anterior approach with the posterior approach for MCM. Then, data extraction and quality assessment were conducted. We used RevMan 5.3 for data analysis. A random effects model was used for heterogenous data, whereas a fixed-effects model was used for homogenous data. Results: A total of 25 nonrandomized controlled studies involving 1843 patients were included. No statistical difference was found with regard to the preoperative Japanese Orthopedic Association (JOA) score between the anterior group and the posterior group (P=0.08, 95% CI, −0.02 to 0.40). The postoperative JOA score and the recovery rate were higher in the anterior group as compared with the posterior group (P=0.02, 95% CI, 0.10–1.33; P=0.006, 95% CI, 2.33–13.90). In the subgroup analysis, better postoperative JOA scores and recovery rates were also obtained in the anterior group for cervical spondylotic myelopathy (P=0.0007, 95% CI, 0.29–1.09; P=0.01, 95% CI, 1.30–9.93). No significant differences were found in the complication rate, the revision rate, the operation time, and blood loss between the 2 groups (P=0.17, 95% CI, 0.89–1.95; P=0.21, 95% CI, 0.72–4.61; P=0.31, 95% CI, −20.20 to 63.30; P=0.88, 95% CI, −166.86 to 143.81). Conclusions: The anterior approach is associated with a better postoperative neurological outcome compared with the posterior approach in cervical spondylotic myelopathy patients. Considering the complication rate, the revision rate, the operation time, and blood loss, the anterior approach appears to be as safe as the posterior approach. Further randomized controlled trials comparing the anterior approach and the posterior approach for MCM should be performed to make a more convincing conclusion.

Intraoperative Myelography in Transpsoas Lateral Lumbar Interbody Fusion for Degenerative Lumbar Spinal Stenosis: A Preliminary Prospective Study

Aim To investigate the feasibility and effectiveness of intraoperative myelography in determining adequacy of indirect spinal canal decompression during transpsoas lateral lumbar interbody fusion (LLIF). Methods Seven patients diagnosed with degenerative lumbar spinal stenosis (DLSS) were prospectively included to this study. All patients underwent LLIF and subsequently received intraoperative myelography to determine the effect of indirect spinal canal decompression, which was visualized in both anterior-posterior and lateral images. Those patients with insufficient indirect canal decompression were further resolved by microendoscopic canal decompression (MECD). Radiological parameters, including stenosis ratio and dural sac area of operated levels, were measured and compared before and after operation. Besides, all patients were followed up for at least one year using visual analogue scale (VAS) for back and leg, Japanese Orthopaedic Association score (JOA), and Oswestry disability index (ODI). Results Seven patients with 8 operated levels underwent LLIF safely and demonstrated significant symptom relief postoperatively. Five operated levels showed adequate indirect canal decompression intraoperatively, while the remaining three levels did not achieve the adequacy, and their residual stenosis was resolved following MECD. Radiological parameters were improved statistically when compared with preoperation (P < 0.05). Furthermore, neurological symptoms of all patients were also improved significantly (P < 0.05), shown by improved VAS (back and leg), JOA, and ODI at both two-week and one-year follow-up. Conclusions Intraoperative myelography during LLIF is able to assess adequacy of indirect canal decompression for DLSS, thus promising favorable clinical outcomes.

Delayed Neurologic Deficit after Thoracolumbar Kyphosis Correction: One Case Report

Study design: Case Report. Objective: To present one case suffering from delayed neurologic deficit after kyphosis deformity correction and analyze its potential etiological factors, how to identify and treat it. Summary of background data: Tardive neurologic deficits occur much less than acute ones after corrections of spinal deformities. Currently some risk factors, such as postoperative hypotension, deformity severity, and intraoperative haemorrhage are considered to be related with its occurrence and worsening though the true mechanisms are not clear. Extrinsic cord compression should be excluded by radiographic examinations before conservative treatments, such as improving blood perfusion, eliminating cord edema, suppressing local inflammation; promoting neurite outgrowth can be applied. If these don’t lead to functional recovery of spinal cord, emergency operation returning the cord to its former kyphotic position can also be considered. Methods: This 44 year-old female patient demonstrated thoracolumbar kyphosis of 136.9° combined with incompetence of spinal cord before operation, and underwent posterior vertebra column resection with the kyphotic correction of 68.8°. No neurologic dysfunction was found during operation. Results: Neurologic deficit appeared on the sixth day after operation, showing motion disability and sensation weakening of both lower extremities. Imaging examinations failed to reveal mechanical compression, such as haematoma or displaced implant. After use of glucocorticoid, gamma globulin, monosialotetrahexosylganglioside, alprostadil and rehabilitation therapies, her myodynamia of both lower extremities recovered greatly, especially muscles extensor, however, her sensation didn’t ameliorate. Conclusions: Delayed-onset neurologic deficit is rarely seen. Detailed history collection and meticulous physical examination are strongly recommended. Early identification and correct treatments can avert incomplete spinal cord from permanent damage.