Adjacent segment degeneration after single- and double-level cervical total disc replacement: a cohort with an over 12-year follow-up.

PURPOSE: To characterize the change of adjacent segment degeneration (ASD) after cervical total disc replacement (CTDR) with more than 12-year follow-up, and identify the risk factors for ASD. METHOD: This process included 75 patients underwent CTDR from February 2004 to December 2012, with the follow-up of 151.9 ± 36.0 (m). The artificial disc included ProDisc-C, Prestige-LP and Mobi-C. ASD was followed up at 1 week, 6 months, 1 year, 2 years, 5 years, 10 years after CTDR and at the endpoint of June 2022. The radiographic measurements were cervical mobility, intervertebral disc height (IDH), cervical lordosis and balance status. The complications were implant migration, subsidence and heterotopic ossification (HO). RESULTS: Cervical mobility in adjacent segments, IDH and lordosis showed no statistical differences between ASD and NASD group. Balance status, subsidence and migration showed no relationship with ASD. Postoperative ASD increased at 6 m and especially between 6 m to 2y. There was no difference between the incidence of upper ASD and lower ASD all the time and few ASD-related reoperation. The majority of adjacent segments were C4/5 (33.6%) and C6/7 (34.2%), and ASD of C5/6 had the highest incidence (61.5%). Cox regression showed ASD was not related to the types of prosthesis or operated numbers. Generalized estimating equations (GEE) analysis showed severe HO had a higher (2.68 times) probability to suffer from ASD. CONCLUSIONS: After over 12-year follow-up of CTDR, the occurrence of ASD and HO had temporal synchronization. ASD was not merely a natural progression but with the pathological process such as HO.

Decompression with fusion is not in superiority to decompression alone in lumbar stenosis based on randomized controlled trials: A PRISMA-compliant meta-analysis.

BACKGROUND: Although some studies had been published, it was more controversial on the superiority of decompression alone (D) and decompression with fusion (F) for the treatment of lumbar spinal stenosis (LSS) recently, especially newest articles with different opinions. A meta-analysis was performed to compare efficacy on D and F for LSS regardless of degenerative spondylolisthesis (DS) with randomized controlled trials (RCTs). METHODS: The databases include PUBMED/MEDLINE, EMBASE, Cochrane Library, and Web of Science from January 1970 to December 2018. The information of screened studies included demographics, clinical outcomes, and secondary measures, then data synthesis and meta-analysis were progressed. Subgroup analysis was stratified by DS and follow-up time (36 months). Continuous variables and dichotomous variables were respectively reported as weighted mean difference and odds ratios (ORs). The strength of evidence was evaluated by the grades of recommendation, assessment, development, and evaluation (GRADE) system. RESULTS: Nine RCTs met inclusion criteria with a total of 857 patients (367 were in D group and 490 were in F group). There were no statistical difference in visual analog scale changes on back and leg pain between D and F group (mean difference [MD] = -0.03, 95% confidence interval [CI] [-0.38, 0.76], z = 0.08, P = .94; MD = 0.11, 95% CI [-1.08, 1.30], z = 0.18, P = .86, respectively); patients' satisfaction was of no difference between the 2 groups, together with the change of the Oswestry disability index and European quality of life-5 dimensions (P > .05). There were no difference in the rate of complication (P = .50) and reoperation (P = .11) while a statistical significance of longer operation duration (P < .0001), more blood loss (P = .004) but amazing lower rate of adjacent segment degenerative/disease (ASD) (OR = 2.35, P = .02) in F group. The subgroup analysis on DS showed that basically all measures were in consistency with meta-analysis. There was a higher reoperation rate in middle-to-long term (>36 months) in D group and ASD was the most seasons of reoperation no matter the follow-up time. According to the GRADE system, the grade of this meta-analysis was of "High" quality. CONCLUSION: F group has no better clinical results than D alone in LSS, regardless of DS and follow-up. The conclusion is of "High" quality and the grade strength of recommendation was "Strong."

Adjacent segment degeneration or disease after cervical total disc replacement: a meta-analysis of randomized controlled trials.

BACKGROUND: Anterior cervical discectomy and fusion (ACDF) has been widely used in cervical spondylosis, but adjacent segment degeneration/disease (ASD) was inevitable. Cervical total disc replacement (TDR) could reduce the stress of adjacent segments and retard ASD in theory, but the superiority has not been determined yet. This analysis aimed that whether TDR was superior to ACDF for decreasing adjacent segment degeneration (ASDeg) and adjacent segment disease (ASDis). METHODS: A meta-analysis was performed according to the guidelines of the Cochrane Collaboration with PubMed, EMBASE, Cochrane Library and CBM (China Biological Medicine) databases. It included randomized controlled trials (RCTs) that reported ASDeg, ASDis, and reoperation on adjacent segments after TDR and ACDF. Two investigators independently selected trials, assessed methodological quality, and evaluated the quality of this meta-analysis using the grades of recommendation, assessment, development, and evaluation (GRADE) approach. RESULTS: Eleven studies with 2632 patients were included in the meta-analysis. The overall rate of ASD in TDR group was lower than ACDF group (OR = 0.6; 95% CI [0.38, 0.73]; P < 0.00001). Both the incidence of ASDeg and the reoperation rate were statistically lower in the TDR group than in the ACDF group (OR = 0.58, P < 0.00001; OR = 0.52, P = 0.01, respectively). Subgroup analysis was performed according to the follow-up time and trial site; the rate of ASDeg was lower in patients underwent TDR no matter the follow-up time, and TDR tended to increase the superiority across time. The rate of ASDeg was also lower with TDR both in the USA and China (P < 0.0001, P = 0.03, respectively). But the cost-effectiveness result might be prone to neither of the two surgery approaches. According to GRADE, the overall quality of this meta-analysis was moderate. CONCLUSIONS: TDR decreased the rates of ASDeg and reoperation compared with that of ACDF, and the superiority may become more apparent over time. We cautiously and slightly suggest adopting TDR according to the GRADE but may not believe it excessively.

[Effects of intrathecal injection of methylprednisolone sodium succinate in acute spinal cord injury rabbits].

OBJECTIVE: To investigate the effects and apoptosis of intrathecal injection of Methylprednisolone Sodium Succinate (MPss) for acute spinal cord injury (SCI) in New Zealand rabbits. METHODS: Seventy-two healthy New Zealand rabbits were used for the procedure and were randomly divided into two groups: SCI group and SHAM group, which was both divided into 6 subgroups, such as the vehicle group, the MPss intrathecal injection groups (1.5 mg/kg, 3.0 mg/kg, 6.0 mg/kg group), the MPss intravenous injection group and the combined injection group. TARLOV score was tested daily to evaluate the motor function. The rabbits were sacrificed 7 days after the surgery and the thoracic spinal cord sections and the sacral sections where MPss was injected were harvested for HE and TUNEL staining. Two-Factors Repeated Measures analysis of variance for TARLOV scores tested at various times and One-Way ANOVA analysis of variance for data between groups were used. RESULT: Seven days after surgery in SCI group, there was no statistical difference between the TARLOV scores of intrathecal injection of MPss 3.0 mg/kg group, 6.0 mg/kg group and MPss intravenous injection group (P > 0.05), which were all better than the vehicle group (F = 4.762, P < 0.05). Referring to the lymphocyte infiltration at the injury site in SCI group, there was statistical difference between MPss intrathecal injection 6.0 mg/kg group (1.33 ± 0.21) and the vehicle group (2.67 ± 0.21) (F = 5.793, P < 0.05) and no statistical difference between intrathecal injection of MPss 6.0 mg/kg group and MPss intravenous injection group (P > 0.05). As for the lymphocyte infiltration at the intrathecal injection site in SHAM group, there was statistical difference between MPss intrathecal injection 6.0 mg/kg group (2.50 ± 0.55) and the vehicle group (0.50 ± 0.55) (F = 17.333, P < 0.05). TUNEL staining in SCI group showed statistical difference between MPss intrathecal injection 6.0 mg/kg group (6.3 ± 1.5) and the vehicle group (20.3 ± 2.2) (F = 71.279, P < 0.05). CONCLUSIONS: Intrathecal injection of MPss can improve the functional recovery of lower limb and decrease apoptosis of neuron cells,which can provide same effects as the traditional intravenous injection of MPss in New Zealand rabbits.

[Long-term clinical outcomes of selective segmental transforaminal lumbar interbody fusion and posterior spinal fusion for degenerative lumbar scoliosis].

OBJECTIVE: To explore the surgical techniques and long-term clinical outcomes of degenerative scoliosis (DS) with selective segmental transforaminal lumbar interbody fusion (TLIF) and posterior spinal fusion. METHODS: Ninety-five patients with adult degenerative lumbar scoliosis undergoing posterior long fusion at our department from January 1999 to December 2007 were analyzed retrospectively. The average follow-up period was 7.8 (5-13) years. The clinical outcomes of Oswestry disability index (ODI), visual analog scale (VAS), patient satisfaction and such radiographic parameters as Cobb angle, apical vertebra translation (AVT), Nash-Moe grade, lumbar lordosis (LL) and thoracolumbar kyphosis (TLK) were evaluated. RESULTS: The clinical outcomes of ODI score and VAS significantly improved at the last visit (P < 0.05). The ODI score was 32.2 ± 8.6 before surgery and 11.1 ± 6.8 at the last visit. The VAS was 8.9 ± 2.0 before surgery and 2.0 ± 1.2 at the last visit. Patient satisfaction was 88.2% (84/95) at the last visit. At the final evaluation, Cobb's angle, apical vertebra translation and Nash-Moe grades decreased with a statistically significant difference (P < 0.001) compared with preoperative parameters.Lordotic angle had a significant increase than preoperative angle (P < 0.001). Thoracolumbar kyphosis showed no significant change (P > 0.05). Besides, a significant positive correlation existed between the decrease of ODI score and the increment of lumbar lordotic angle (r = 0.62, P = 0.01) .Long-term complications included broken rod (n = 2), coronal junctional scoliosis (n = 4), L5-S1 spondylolisthesis (n = 2), L5-S1 restenosis (n = 5). And 11 patients underwent reoperation. CONCLUSION: A combination of selective segmental TLIF and posterior spinal fusion is both safe and effective for degenerative scoliosis and excellent long-term clinical outcomes may be achieved. And selective segmental TLIF can facilitate solid fusion, improvement of lumbar lordosis, better correction of lateral spondylolisthesis and asymmetric disc space so as to yield better corrective effects and long-term clinical outcomes.

[Comparison of allogenic versus ostetic artificial bone in double door laminoplasty].

OBJECTIVE: To study the application of allogenic bone and Ostetic artificial bone in double door laminoplasty. METHODS: From June 2004 to June 2010, a total of 111 patients underwent double door laminoplasty. And allogenic (group A, n = 63) and Ostetic artificial (group B, n = 48) bones were used. They had spinal stenosis at least several levels or OPLL (Ossification of posterior longitudinal ligament). Their follow-up period was 12 months. Anteroposterior compression ratio was used to evaluate the neurological status. Range-of-movement (ROM) of cervical spine and bone fusion was determined by radiography and computed tomography (CT) during the follow-ups. RESULTS: Anteroposterior compression ratio: group A improved from 0.18 preoperation to 0.43 postoperation while group B increased from 0.20 preoperation to 0.44 postoperation; ROM: group A decreased postoperatively to (22.6 ± 3.3)° from (39.5 ± 6.1)° while group B decreased postoperatively to (22.9 ± 3.7)° from (39.3 ± 6.7)°. When Groups A and B were compared, bone fusion between allograft and spinous processes was completed in 73.1% vs 64.2%, partial fusion in 22.4% vs 18.7% and failed in 6.3% vs 17.1%. CONCLUSION: Uses allogenic and Ostetic artificial bones in double door laminoplasty may achieve an excellent decompression of spinal cord. But the application of allogenic bone yields a higher bone fusion rate after surgery.

[Experimental correlation study of lumbar spinal stenosis and knee joint degeneration].

OBJECTIVE: To explore the correlation of lumbar stenosis and knee osteoarthritis by establishing a rabbit lumbar spinal stenosis model and observing the hind limb movement function and pathological change of articular cartilage of knee joint. METHODS: A total of 36 healthy adult rabbits were randomly divided into model group and control group. In the model group, spinal canal was filled with bone pieces to make lumbar spinal stenosis; in the control group, sham operation was performed and materials were inserted into spinal canal. Movement function was evaluated by Tarlov method and pathological features were observed by Mankin's scores under light microscope at 4, 8 and 12 weeks. RESULTS: Early degenerative changes of knee cartilage were observed in the model group at 4 and 8 weeks post-operation. There were synovial hyperemia and hyperplasia, increased synovial fluid effusion and lightly-stained cartilage. The Mankin score was 3.3 - 4.5 and Tarlov score 3 - 4. Intermediate stage changes of osteoarthritis were found in the model group at 12 weeks post-operation, showing synovial hyperplasia, decreased synovial fluid, fissure in cartilage surface, tangled cartilage cells and unevenly stained matrix. The Mankins score was 7 - 9 and Tarlov score 2 - 3. Most of articular cartilage was normal in the control group with Mankin score of 0 - 1 and Tarlov score of 4. CONCLUSION: Lumbar stenosis may be correlated with knee joint degeneration.

[Surgical treatment of multilevel lumbar degenerative spondylolisthesis].

OBJECTIVE: To discuss the surgical treatment of multilevel lumbar degenerative spondylolisthesis. METHODS: From March 2005 to September 2008, 25 cases of multilevel lumbar degenerative spondylolisthesis were treated with total laminectomy, reduction of spondylolisthesis and 360 degrees circumferential fusion through interbody (PLIF), transverse process (PLF) and pedicle screw fixation. All cases were followed up for 0.5 - 4 years. The Lenke grading system was used to assess the spinal fusion and Henderson grading system was used to assess the clinical outcomes. RESULTS: Complete reduction of spondylolisthesis was achieved in all cases. The bone fusion was grade A in 23 cases, grade B in 2 cases. The clinical outcome was excellent in 16 cases, good in 6 cases and poor in 3 cases. CONCLUSIONS: The pathogenesis of lumbar degenerative multilevel spondylolisthesis is different from that of single-level spondylolisthesis. Complete decompression, reduction of spondylolisthesis sufficient fusion and reliable pedicle screw fixation can provide successful interbody fusion and satisfactory clinical results.It's crucial to reduce multilevel spondylolisthesis by proper techniques based on different types of listhesis.

[Transforaminal lumbar interbody fusion in treatment of upper lumbar disc herniation: analysis of 18 cases].

OBJECTIVE: To study the effectiveness and advantages of transforaminal lumbar interbody fusion (TLIF) in the treatment of upper lumbar disc herniation. METHODS: Eighteen cases with upper lumbar disc herniation, 12 males and 6 females, aged 21 - 67, underwent TLIF. Follow-up was conducted for 19.8 months (12 - 54 months). The surgical process, outcomes, and complications were reviewed retrospectively. In TLIF operation, pedicle screw fixation was performed first, unilateral or bilateral facet joints were then excised. Disc removal and titanium mesh or fusion cage insertion were completed via transforaminal approach. RESULTS: Unilateral TLIF was performed in 14 cases and bilateral TLIF was accomplished in 4 cases. The mean operation time was 82.4 minutes and the intraoperative blood loss was 323 ml. No injury of spinal cord or nerve roots happened during the operation. The follow-up showed that the operation results were excellent in 11 cases, good in 4 cases, and fair in 3 cases. No worsening or relapse of preoperative symptoms was observed. Disc spaces and lumbar lordosis were restored satisfactorily. No internal fixation failure was found. CONCLUSION: Able to excise disc completely, restore physiological lumbar curve effectively and prevent postoperative instability, TLIF is one of effective surgical treatments for upper lumbar disc herniation for selected patients.