Interspinous process device versus standard conventional surgical decompression for lumbar spinal stenosis: randomized controlled trial

Brief review

이 논문은 요추 협착증의 치료방법으로서 극돌기간 삽입체와 기존의 감압술을 비교한 무작위 대조군 연구 입니다.

술 후 8주 이내의 짧은 기간 내에서, 극돌기간 고정체 삽입술이 감압술에 비해 효과적인가를 평가하기 위한 것이 목적 입니다.

2008년 10월부터 2011년 9월까지 1 or 2분절에 요추 협착증이 있어 NIC(신경성 간헐적 보행장애)를 보이는 환자 159명을 대상으로 무작위, 이중맹검으로 수술을 시행하였고, 수술 후 8주차, 1년차에 각각 ZCQ(보행장애와 관련된 설문)을 통해 success rate를 평가했습니다.

평가결과, 8주차에는 interspinous그룹이 decompression그룹에 비해 성공률이 월등히 높지는 않았고, 1년 차에도 두 그룹간에 차이가 없었습니다.

결론적으로, 이 연구에서는 단기간 내, interspinous process device 삽입술이 decompression에 비해 우수하다는 것을 증명하지 못했으며, 오히려 interspinous process device삽입술이 decompression에 비해 유의하게 재 수술률이 높은 것으로 나타났습니다.

*Title: Interspinous process device versus standard conventional surgical decompression for lumbar spinal stenosis: randomized controlled trial.

*Authors: Moojen WA, Arts MP, Jacobs WC, van Zwet EW, van den Akker-van Marle ME, Koes BW, Vleggeert-Lankamp CL, Peul WC

*Bibliography: BMJ.2013 Nov 14; 347: f6415.

OBJECTIVE

To assess whether interspinous process device implantation is more effective in the short term than conventional surgical decompression for patients with intermittent neurogenic claudication due to lumbar spinal stenosis.

DESIGN

Randomized controlled trial

(prospective, randomized, double blind, multicenter trial)

SETTING

5neurosurgical centers (including one academic and four secondary level care centers) in the Netherlands.

PARTICIPANTS

▶Enrollment period: 2008.10~2011.09

▶Subject number: 159 participants (with intermittent neurogenic claudication due to lumbar spinal stenosis at 1 or 2 levels)

INTERVENTIONS

Total 159 patients (80 interspinous process device group + 79 spinal bony decompression group)

MAIN OUTCOME MEASURES

▶Measurement method: Zurich Claudication Questionnaire score (ZCQ)

▶Follow-up period: 1) primary outcome at short term (8weeks), 2) long term (1year)

-Repeated measurements were made to compare outcomes over time.

RESULTS

▶Success rate(ZCQ)

1) short term F/U(8wks): interspinous process device group (63%, 95% confidence interval 51% to 73%) was not superior to that for standard bony decompression (72%, 60% to 81%).

2) long term F/U(1yr): No differences in disability (ZCQ; p=0.44) or other outcomes were observed between groups

-The repeat surgery rate: interspinous implant group was substantially higher (n=21; 29%) than that in the conventional group (n=6; 8%) in the early post-surgical period (P<0.001).

CONCLUSIONS

-This double blinded study could not confirm the hypothesized short term advantage of interspinous process device over conventional "simple" decompression.

-After interspinous process device implantation, showed a fairly high reoperation rate.

Risk of infection following posterior instrumented lumbar fusion for degenerative spine disease in 817 consecutive cases

Brief review

이 논문은 퇴행성 척추질환으로 후방경유 요추 유합술을 시행한 817명의 환자 데이터를 리뷰하여 감염에 영향을 끼칠 수 있는 요소를 밝힌 논문 입니다.

감염과 연관된 요소를 밝히기 위해 ‘단계적 다변량 비례 위험도 회기 분석법’을 이용하였습니다.

결과적으로, 연령의 증가와 당뇨병, 비만, 이전의 척추수술 경험 및 재원일수의 증가 등이 후방 경유 요추 유합술 후의 감염의 위험성을 증가시킬 수 있는 요인으로 드러났습니다.

*Title: Risk of infection following posterior instrumented lumbar fusion for degenerative spine disease in 817 consecutive cases

퇴행성 척추질환으로 후방 경유 요추 유합술을 시행한 817명 환자들의 감염 위험성

*Authors: Kaisorn L. Chaichana, M.D., Mohamad Bydon, M.D., David R. Santiago-Dieppa, M.D., Lee Hwang, M.D., Gregory McLoughlin, M.D., Daniel M. Sciubba, M.D., Jean-Paul Wolinsky, M.D., Ali Bydon, M.D., Ziya L. Gokaslan, M.D., and Timothy Witham, M.D.Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, Maryland

*Bibliography: J Neurosurg Spine 20:45–52, 2014

Summary of Background

Posterior lumbar spinal fusion for degenerative spine disease is a common procedure, and its use is increasing annually. The rate of infection, as well as the factors associated with an increased risk of infection, remains unclear for this patient population. A better understanding of these features may help guide treatment strategies aimed at minimizing infection for this relatively common procedure.

Object

To ascertain the incidence of postoperative spinal infections and identify factors associated with postoperative spinal infections.

Methods

▶Subject: patients underwent instrumented posterior lumbar fusion for degenerative spine disease (1993~2010)

“Stepwise multivariate proportional hazards regression analysis” was used to identify factors associated with infection.

Variables with p < 0.05 were considered statistically significant.

Results

▶Total subjects: 817 patients underwent lumbar fusion

▶Infection patients: 37(4.5%)

-21 (57%) required operative intervention but only 3 (8%) required instrumentation removal as part of their infection management.

▶The factors independently associated with an increased risk of infection.

1) increasing age (RR 1.004 [95% CI 1.001–1.009], p = 0.049)

2) diabetes (RR 5.583 [95% CI 1.322–19.737], p = 0.02)

3) obesity (RR 6.216 [95% CI 1.832–9.338], p = 0.005)

4) previous spine surgery (RR 2.994 [95% CI 1.263–9.346], p = 0.009)

5) increasing duration of hospital stay (RR 1.155 [95% CI 1.076–1.230], p = 0.003)

Conclusions

-older age, diabetes, obesity, prior spine surgery, and length of hospital stay: independently associated with an increased risk of infection in lumbar fusion for degenerative spine disease

-The overwhelming majority of these patients were treated effectively without hardware removal.

Risk of infection following posterior instrumented lumbar fusion for degenerative spine disease in 817 consecutive cases.

Brief review

이 논문은 퇴행성 척추질환 때문에 후방경유 요추 유합술을 받은 817명의 환자에게 나타난 감염률과 감염에 영향을 끼치는 요소들을 연구한 논문 입니다.

후향적으로 환자의 데이터를 검토하여 감염률을 조사했고, 단계적 다변량 비례 위험 회귀분석법을 통하여 요추감염과 연관성이 있는 요소들을 알아냈습니다.

연구대상인 817명의 환자에 대해서는 감염률이 4.5%로 나타났고,  나이, 당뇨지수, 비만도, 이전에 척추수술을 시행했는지의 여부, 재원기간 등의 요소들이 감염에 영향을 끼치는 것으로 나타났습니다.

*Title: Risk of infection following posterior instrumented lumbar fusion for degenerative spine disease in 817 consecutive cases.

퇴행성 척추질환으로 후방경유 요추 유합술을 시행한 817명의 사례에 대한 감염의 위험성

*Author: Kaisorn L. Chaichana, Mohamad Bydon, David R. Santiago-Dieppa, Lee Hwang, Gregory McLoughlin, Daniel M. Sciubb a, Jean-Paul Wolinsky, Ali Bydon, Ziya L. Gokaslan, Timothy Witham

*Bibliography: J Neurosurg Spine. 2013 Nov 8. [Epub aheadof print]

Object

The rate and factors of infection risk remains unclear for Posterior lumbar spinal fusion (for degenerative spine disease)

Purpose: To ascertain the incidence and factors of postoperative spinal infections.

Methods

▶Period: 1993 ~ 2010

▶Subject: 817 patients who underwent posterior lumbar fusion for degenerative disease.

-Retrospectively data reviewed.

-To identify the infection factors, using Stepwise multivariate proportional hazards regression analysis.

Results

1. Infection rate: 4.5%

(37 patients out of 817 patients developed postoperative spine infection at a median of 0.6 months (IQR 0.3-0.9) ).

2. Infection factors

1. age (RR 1.004 [95% CI 1.001-1.009], p = 0.049)

2. diabetes (RR 5.583 [95% CI 1.322-19.737], p = 0.02)

3. obesity (RR 6.216 [95% CI 1.832-9.338], p = 0.005)

4. previous spine surgery (RR 2.994 [95% CI 1.263-9.346], p = 0.009)

5. duration of hospital stay (RR 1.155 [95% CI 1.076-1.230], p = 0.003).

Conclusions

-Several factors were associated with an risk of infection among patients underwent lumbar fusion for degenerative disease. (factors: older age, diabetes, obesity, prior spine surgery, and length of hospital stay) 

Does the presence of the nerve root sedimentation sign on MRI correlate with the operative level in patients undergoing posterior lumbar decompression for lumbar stenosis?

Brief review 1

*Title: Does the presence of the nerve root sedimentation sign on MRI correlate with the operative level in patients undergoing posterior lumbar decompression for lumbar stenosis?

*Authors: Akil Fazal, MD,  Andrew Yoo, BA,  John A. Bendo, MD

*Bibliography: Spine J. 2013 Aug;13(8):837-42.

BACKGROUND CONTEXT:

-Recent research describes the use of a nerve root sedimentation sign to diagnose lumbar spinal stenosis (LSS).

-The lack of sedimentation of the nerve roots (positive sedimentation sign) to the dorsal part of the dural sac is the characteristic feature of this new radiological parameter.

PURPOSE: To demonstrate how the nerve root sedimentation sign compares with other more traditional radiological parameters in patients who have been operated for LSS.

STUDY DESIGN/SETTING: A retrospective chart and image review.

PATIENT SAMPLE: Preoperative MRI were reviewed from 71 consecutive operative patients who presented with LSS and received spinal decompression surgery (2006-2010).

OUTCOME MEASURES: Preoperative T2-weighted MRIs were reviewed for each patient.

METHODS:

▶Measurements

134 vertebral levels (L1-5) were measured for

1)     sedimentation sign

2)     cross-sectional area (CSA)

3)     anterior/posterior (A/P) diameter of the dural sac

4)     thickness of the ligamentum flavum

5)     Fujiwara grade of facet hypertrophy.

-using Surgimap 1.1.2.169 software (Nemaris, Inc., New York, NY, USA)

-Exclusion criteria: 1) previous spine surgeries 2) absence of MRI on extended dynamic range 3) surgeries for primary diagnosis other than LSS

▶Statistical analyses

-using the SPSS 17.0 statistical software (SPSS Inc., Chicago, IL, USA).

-Significance was demonstrated using unpaired t tests and chi-squared tests.

RESULTS: The measurements are listed below.

CONCLUSIONS:

-The sign is most often present in patients who have clinically significant lumbar stenosis and require surgery.

-The sedimentation sign is a new measurement tool that can enable physicians to objectively assess and quantify spinal stenosis.

*Fujiwara grading system: aim to assess the severity of the facet joint osteoarthritis.

REFERENCE: Fujiwara A, Tamai K, Yamato M, et al. The relationshipbetween facet joint osteoarthritis and disc degeneration of the lumbar spine: anMRI study. Eur Spine J 1999;8:396–401.