Lumbar laminectomy alone or with instrumented or noninstrumented arthrodesis in degenerative lumbar spinal stenosis. Patient selection, costs, and surgical outcomes

Assessment and treatment of abuse risk in opioid prescribing for chronic pain

Opioid analgesics provide effective treatment for noncancer pain, but many physicians have concerns about adverse effects, tolerance, and addiction. Misuse of opioids is prominent in patients with chronic back pain and early recognition of misuse risk could help physicians offer adequate patient care while implementing appropriate levels of monitoring to reduce aberrant drug-related behaviors. In this review, we discuss opioid abuse and misuse issues that often arise in the treatment of patients with chronic back pain and present an overview of assessment and treatment strategies that can be effective in improving compliance with the use of prescription opioids for pain. Many persons with chronic back pain have significant medical, psychiatric and substance use comorbidities that affect treatment decisions and a comprehensive evaluation that includes a detailed history, physical, and mental health evaluation is essential. Although there is no "gold standard" for opioid misuse risk assessment, several validated measures have been shown to be useful. Controlled substance agreements, regular urine drug screens, and interventions such as motivational counseling have been shown to help improve patient compliance with opioids and to minimize aberrant drug-related behavior. Finally, we discuss the future of abuse-deterrent opioids and other potential strategies for back pain management.

Complications related to instrumentation in spine surgery: a prospective analysis

Object

Prospective examination of perioperative complications in spine surgery is limited in the literature. The authors prospectively collected data on patients who underwent spinal fusion at a tertiary care center and evaluated the effect of spinal fusion and comorbidities on perioperative complications.

Methods

Between May and December 2008 data were collected prospectively in 248 patients admitted to the authors' institution for spine surgery. The 202 patients undergoing spine surgery with instrumentation were further analyzed in this report. Perioperative complications occurring within the initial 30 days after surgery were included. All adverse occurrences, whether directly related to surgery, were included in the analysis.

Results

Overall, 114 (56.4%) of 202 patients experienced at least one perioperative complication. Instrumented fusions were associated with more minor complications (p = 0.001) and more overall complications (0.0024). Furthermore, in the thoracic and lumbar spine, complications increased based on the number of levels fused. Advanced patient age and certain comorbidities such as diabetes, cardiac disease, or a history of malignancy were also associated with an increased incidence of complications.

Conclusions

Using a prospective methodology with a broad definition of complications, the authors report a significantly higher perioperative incidence of complications than previously indicated after spinal fusion procedures. Given the increased application of instrumentation, especially for degenerative disease, a better estimate of clinically relevant surgical complications could aid spine surgeons and patients in an individualized complication index to facilitate a more thorough risk-benefit analysis prior to surgery.

Cost-effectiveness of multilevel hemilaminectomy for lumbar stenosis-associated radiculopathy

BACKGROUND CONTEXT

Laminectomy for lumbar stenosis-associated radiculopathy is associated with improvement in pain, disability, and quality of life. However, given rising health-care costs, attention has been turned to question the cost-effectiveness of lumbar decompressive procedures. The cost-effectiveness of multilevel hemilaminectomy for radiculopathy remains unclear.

PURPOSE

To assess the comprehensive medical and societal costs of multilevel hemilaminectomy at our institution and determine its cost-effectiveness in the treatment of degenerative lumbar stenosis.

STUDY DESIGN

Prospective single cohort study.

PATIENT SAMPLE

Fifty-four consecutive patients undergoing multilevel hemilaminectomy for lumbar stenosis-associated radiculopathy after at least 6 months of failed conservative therapy were included.

OUTCOME MEASURES

Self-reported measures were assessed using an outcomes questionnaire that incorporated total back-related medical resource utilization, missed work, and improvement in leg pain (visual analog scale for leg pain [VAS-LP]), disability (Oswestry Disability Index [ODI]), quality of life (Short Form-12 [SF-12]), and health state values (quality-adjusted life years [QALYs], calculated from EuroQuol 5D [EQ-5D] with US valuation).

METHODS

Over a 2-year period, total back-related medical resource utilization, missed work, and improvement in leg pain (VAS-LP), disability (ODI), quality of life (SF-12), and health state values (QALYs, calculated from EQ-5D with US valuation) were assessed. Two-year resource use was multiplied by unit costs based on Medicare national allowable payment amounts (direct cost), and patient and caregiver workday losses were multiplied by the self-reported gross-of-tax wage rate (indirect cost). Mean total 2-year cost per QALY gained after multilevel hemilaminectomy was assessed.

RESULTS

Compared with preoperative health states reported after at least 6 months of medical management, a significant improvement in VAS-LP, ODI, and SF-12 (physical and mental components) was observed 2 years after multilevel hemilaminectomy, with a mean 2-year gain of 0.72 QALYs. Mean±standard deviation total 2-year cost of multilevel hemilaminectomy was $24,264±10,319 (surgery cost, $10,220±80.57; outpatient resource utilization cost, $3,592±3,243; and indirect cost, $10,452±9,364). Multilevel hemilaminectomy was associated with a mean 2-year cost per QALY gained of $33,700.

CONCLUSIONS

Multilevel hemilaminectomy improved pain, disability, and quality of life in patients with lumbar stenosis-associated radiculopathy. Total cost per QALY gained for multilevel hemilaminectomy was $33,700 when evaluated 2 years after surgery with Medicare fees, suggesting that multilevel hemilaminectomy is a cost-effective treatment of lumbar radiculopathy.

To fuse or not to fuse in lumbar degenerative spondylolisthesis: do baseline symptoms help provide the answer?

INTRODUCTION

Clinical symptoms in lumbar degenerative spondylolisthesis (LDS) vary from predominantly radiating pain to severe mechanical low back pain. We examined whether the outcome of surgery for LDS varied depending on the predominant baseline symptom and the treatment administered [decompression with fusion (D&F) or decompression alone (D)].

METHODS

213 consecutive patients (69 ± 9 years; 155f, 58 m) participated. Inclusion criteria were LDS, maximum three affected levels, no previous surgery at the affected level, and D (N = 56) or D&F (N = 157) as the operative procedure. Pre-op and at 12 months' follow-up (FU), patients completed the multidimensional Core Outcome Measures Index (COMI) including 0-10 leg-pain (LP) and LBP scales. At 12 months' FU, patients rated global outcome which was then dichotomised into "good" and "poor".

RESULTS

Pre-operatively, LBP and COMI scores were significantly worse (p < 0.05) in the D&F group than in the D group. The improvement in COMI at 12 months' FU was significantly greater for D&F than for D (p < 0.001) and was not influenced by the patient's declared "main problem" at baseline (back pain, leg pain, or neurological disturbances) (p > 0.05). There was a higher proportion (p = 0.01) of "good" outcomes at 12 months' FU in D&F (86%) than in D (70%). Multiple regression analysis, controlling for possible confounders, revealed treatment group to be the only significant predictor of outcome (adding fusion = better outcome).

DISCUSSION

Our study indicated that LDS patients showed better patient-based outcome with instrumented fusion and decompression than with decompression alone, regardless of baseline symptoms. This may be due to the fact that the underlying slippage as the cause of the stenosis is better addressed with fusion.

Spinaplasty following lumbar laminectomy for multilevel lumbar spinal stenosis to prevent iatrogenic instability

BACKGROUND

Iatrogenic instability following laminectomy occurs in patients with degenerative lumbar canal stenosis. Long segment fusions to obviate postoperative instability result in loss of motion of lumbar spine and predisposes to adjacent level degeneration. The best alternative would be an adequate decompressive laminectomy with a nonfusion technique of preserving the posterior ligament complex integrity. We report a retrospective analysis of multilevel lumbar canal stenosis that were operated for posterior decompression and underwent spinaplasty to preserve posterior ligament complex integrity for outcome of decompression and iatrogenic instability.

MATERIALS AND METHODS

610 patients of degenerative lumbar canal stenosis (n=520) and development spinal canal stenosis (n=90), with a mean age 58 years (33-85 years), underwent multilevel laminectomies and spinaplasty procedure. At followup, changes in the posture while walking, increase in the walking distance, improvement in the dysesthesia in lower limb, the motor power, capability to negotiate stairs and sphincter function were assessed. Forward excursion of vertebrae more than 4 mm in flexion-extension lateral X-ray of the spine as compared to the preoperative movements was considered as the iatrogenic instability. Clinical assessment was done in standing posture regarding active flexion-extension movement, lateral bending and rotations

RESULTS

All patients were followed up from 3 to 10 years. None of the patients had neurological deterioration or pain or catch while movement. Walking distance improved by 5-10 times, with marked relief (70-90%) in neurogenic claudication and preoperative stooping posture, with improvement in sensation and motor power. There was no significant difference in the sagittal alignment as well as anterior translation. Two patients with concomitant scoliosis and one with cauda equine syndrome had incomplete recovery. Two patients who developed disc protrusion, underwent a second operation for a symptomatic disc prolapse.

CONCLUSION

Spinaplasty following posterior decompression for multilevel lumbar canal stenosis is a simple operation, without any serious complications, retaining median structures, maintaining the tension band and the strength with least disturbance of kinematics, mobility, stability and lordosis of the lumbar spine.

Clinical outcomes of degenerative lumbar spinal stenosis treated with lumbar decompression and the Cosmic "semi-rigid" posterior system

Background

Although some investigators believe that the rate of postoperative instability is low after lumbar spinal stenosis surgery, the majority believe that postoperative instability usually develops. Decompression alone and decompression with fusion have been widely used for years in the surgical treatment of lumbar spinal stenosis. Nevertheless, in recent years several biomechanical studies have shown that posterior dynamic transpedicular stabilization provides stabilization that is like the rigid stabilization systems of the spine. Recently, posterior transpedicular dynamic stabilization has been more commonly used as an alternative treatment option (rather than rigid stabilization with fusion) for the treatment of degenerative spines with chronic instability and for the prevention of possible instability after decompression in lumbar spinal stenosis surgery.

Methods

A total of 30 patients with degenerative lumbar spinal stenosis (19 women and 11 men) were included in the study group. The mean age was 67.3 years (range, 40–85 years). Along with lumbar decompression, a posterior dynamic transpedicular stabilization (dynamic transpedicular screw–rigid rod system) without fusion was performed in all patients. Clinical and radiologic results for patients were evaluated during follow-up visits at 3, 12, and 24 months postoperatively.

Results

The mean follow-up period was 42.93 months (range, 24–66 months). A clinical evaluation of patients showed that, compared with preoperative assessments, statistically significant improvements were observed in the Oswestry and visual analog scale scores in the last follow-up control. Compared with preoperative values, there were no statistically significant differences in radiologic evaluations, such as segmental lordosis angle (α) scores (P = .125) and intervertebral distance scores (P = .249). There were statistically significant differences between follow-up lumbar lordosis scores (P = .048). There were minor complications, including a subcutaneous wound infection in 2 cases, a dural tear in 2 cases, cerebrospinal fluid fistulas in 1 case, a urinary tract infection in 1 case, and urinary retention in 1 case. We observed L5 screw loosening in 1 of the 3-level decompression cases. No screw breakage was observed and no revision surgery was performed in any of these cases.

Conclusions

Posterior dynamic stabilization without fusion applied to lumbar decompression leads to better clinical and radiologic results in degenerative lumbar spinal stenosis. To avoid postoperative instability, especially in elderly patients who undergo degenerative lumbar spinal stenosis surgery with chronic instability, the application of decompression with posterior dynamic transpedicular stabilization is likely an important alternative surgical option to fusion, because it does not have fusion-related side effects, is easier to perform than fusion, requires a shorter operation time, and has low morbidity and complication rates.

Validity and reproducibility of self-report measures of walking capacity in lumbar spinal stenosis

STUDY DESIGN

Measurement (validity) study.

OBJECTIVE

Examine validity and reproducibility of self-report measures of walking capacity for use in patients with lumbar spinal stenosis (LSS).

SUMMARY OF BACKGROUND DATA

Treatment outcomes in patients with LSS are often determined using data from self-report questionnaires. Despite some validity evidence available to support the use of self-report instruments in the evaluation of walking capacity in LSS, it is not certain that the construct being tapped using any of the self-report measures is, in fact, walking capacity.

METHODS

Validity of the Physical Function Scale of the Swiss Spinal Stenosis Questionnaire, the Oswestry Disability Index (ODI), self-predicted walking capacity (distance in meters) and a number of single item walking capacity questions was evaluated through comparison with a criterion measure of walking capacity, the Self-Paced Walking Test, in patients with LSS. Test-retest reproducibility was also examined for each of the self-report measures.

RESULTS

Subjects included 49 patients (65.8 ± 10.0 years of age) with LSS confirmed on imaging and by a spine specialist surgeon. The measures found to be most highly associated with the criterion Self-Paced Walking Test were the walking distance item from the ODI (r = 0.83) and self-reported walking capacity in meters (with the aid of a distance reference) (r = 0.80). Reported walking capacity in meters had the lowest test-retest reproducibility (intraclass correlation coefficient = 0.65) of the measures studied.

CONCLUSION

This study provides new information to help guide health professionals and researchers in the selection of appropriate outcome tools when examining walking in an LSS population. Study results support the use of the Physical Function Scale, self-reported walking distance, and the walking specific items from the ODI and the Physical Function Scale.

Surgical treatment patterns among Medicare beneficiaries newly diagnosed with lumbar spinal stenosis

BACKGROUND CONTEXT

Lumbar spinal stenosis (LSS) is a prevalent degenerative condition in the elderly that can be managed medically or with surgical treatments. Recent studies have shown an increase in the utilization of surgery in the United States and great regional variations. An understanding of treatment patterns and costs in a population-based setting will help identify subgroup differences to help inform strategies for optimal care in patients with LSS.

PURPOSE

This study sought to examine surgical treatment rate and types, time to treatment, and patient characteristics that affect treatment patterns for newly diagnosed LSS in the US Medicare population.

STUDY DESIGN

A retrospective longitudinal study of administrative claims was performed on a 5% randomly selected sample of Medicare beneficiaries.

PATIENT SAMPLE

Six thousand two hundred sixty-five Medicare beneficiaries newly diagnosed with LSS in the first quarter of 2003 were identified and followed until the end of 2005.

OUTCOME MEASURES

Rate of LSS surgery, type and timing of LSS surgery, and Medicare costs.

METHODS

A "de novo" LSS patient cohort was defined as those with claims with a primary diagnosis of LSS during the period of January to March 2003, excluding those with a LSS diagnosis in 2002. These patients were stratified into surgery and nonsurgery cohorts based on the presence of procedure codes for LSS surgery. The surgery cohort was further divided into three subgroups: laminectomy or laminotomy only; fusion only; and fusion with laminectomy or laminotomy. All Medicare claims for these patients were extracted and reviewed through December 2005. Descriptive statistics were carried out for demographic characteristics, comorbidities, treatment rates, and Medicare costs.

RESULTS

This study indicated that 21% of LSS patients underwent surgery within 3 years of initial diagnosis. Surgery skews toward the healthier and younger patients. Overall, 78% of LSS surgeries were performed in the year of diagnosis, 13% in the second, and 9% in the third. Although laminectomies and laminotomies were the most frequently performed procedures across all years, a higher percentage of fusions were performed in addition to laminectomy or laminotomy in the second or third years after diagnosis than in the first year. The 3-year Medicare payments were $49,624 in the surgery cohort in comparison with $36,691 in the nonsurgery cohort. Patients who underwent a laminectomy/laminotomy alone incurred significantly lower Medicare payments ($42,293) than those who had fusion alone ($57,171) or laminectomy/laminotomy plus fusion ($63,555).

CONCLUSIONS

The surgical management of LSS varies with respect to timing and type of surgery provided. Such variation needs to be explained beyond demographic and comorbid factors.

Treatment of lumbar spinal stenosis: a balancing act

Chen E, Tong KB, Laouri M. Surgical treatment patterns among Medicare beneficiaries newly diagnosed with lumbar spinal stenosis. Spine J 2010;10:588-594 (in this issue).

[Microsurgical decompression of lumbar spinal stenosis]

Lumbar spinal stenosis in most cases is due to progressive degeneration of the spine, resulting in thickening of facet joints and flaval ligament. Thus the diameter of the lumbar spinal canal is reduced to less than 12 mm in the AP direction. Typically complaints consist in neurogenic claudication. Patients usually experience improvement of pain when bending their back or walking up a hill. Diagnosis of lumbar spinal stenosis is confirmed by MRI. CT myelography may help detect where compression is most pronounced. Surgical treatment should be based on the clinical symptoms of the mostly elderly people and should be performed as microsurgical decompression or in cases of clinical instability as TLIF.

Comparison of posterior dynamic and posterior rigid transpedicular stabilization with fusion to treat degenerative spondylolisthesis

This article describes the clinical and radiological outcomes of a comparison of posterior dynamic transpedicular stabilization and posterior rigid transpedicular stabilization with fusion after decompression in the treatment of degenerative spondylolisthesis. This prospective clinical and radiologic study was conducted between 2004 and 2007 and included 46 patients, of whom 33 were women (71.7%) and 13 were men (28.3%). Mean patient age was 61.67+/-10.80 years (range, 45-89 years). Twenty-six patients who underwent lumbar decompression and posterior dynamic transpedicular stabilization were followed for a mean of 38 months (range, 24-55 months). In the fusion group, 20 patients who underwent lumbar decompression and rigid stabilization with fusion were followed for a mean of 44 months (range, 26-64 months). The intervertebral space measurements of the dynamic group at the preoperative examination and at 12 and 24 months postoperatively were statistically significantly higher than the intervertebral space measurements of the fusion group (P<.05). In the dynamic group, complications occurred in 2 patients; the first was a screw malposition, which was improved with revision surgery within 1 month of the initial surgery, and the second was a fusion performed in the second year in 1 patient because the patient reported continued pain. In the fusion group, adjacent segment disease was observed in 1 patient, with subsequent reoperation. Lumbar decompression and posterior dynamic transpedicular stabilization yield satisfactory results in the treatment of degenerative lumbar spondylolisthesis and can be considered a valid alternative to fusion.

Trends, major medical complications, and charges associated with surgery for lumbar spinal stenosis in older adults

CONTEXT

In recent decades, the fastest growth in lumbar surgery occurred in older patients with spinal stenosis. Trials indicate that for selected patients, decompressive surgery offers an advantage over nonoperative treatment, but surgeons often recommend more invasive fusion procedures. Comorbidity is common in older patients, so benefits and risks must be carefully weighed in the choice of surgical procedure.

OBJECTIVE

To examine trends in use of different types of stenosis operations and the association of complications and resource use with surgical complexity.

DESIGN, SETTING, AND PATIENTS

Retrospective cohort analysis of Medicare claims for 2002-2007, focusing on 2007 to assess complications and resource use in US hospitals. Operations for Medicare recipients undergoing surgery for lumbar stenosis (n = 32,152 in the first 11 months of 2007) were grouped into 3 gradations of invasiveness: decompression alone, simple fusion (1 or 2 disk levels, single surgical approach), or complex fusion (more than 2 disk levels or combined anterior and posterior approach).

MAIN OUTCOME MEASURES

Rates of the 3 types of surgery, major complications, postoperative mortality, and resource use.

RESULTS

Overall, surgical rates declined slightly from 2002-2007, but the rate of complex fusion procedures increased 15-fold, from 1.3 to 19.9 per 100,000 beneficiaries. Life-threatening complications increased with increasing surgical invasiveness, from 2.3% among patients having decompression alone to 5.6% among those having complex fusions. After adjustment for age, comorbidity, previous spine surgery, and other features, the odds ratio (OR) of life-threatening complications for complex fusion compared with decompression alone was 2.95 (95% confidence interval [CI], 2.50-3.49). A similar pattern was observed for rehospitalization within 30 days, which occurred for 7.8% of patients undergoing decompression and 13.0% having a complex fusion (adjusted OR, 1.94; 95% CI, 1.74-2.17). Adjusted mean hospital charges for complex fusion procedures were US $80,888 compared with US $23,724 for decompression alone.

CONCLUSIONS

Among Medicare recipients, between 2002 and 2007, the frequency of complex fusion procedures for spinal stenosis increased while the frequency of decompression surgery and simple fusions decreased. In 2007, compared with decompression, simple fusion and complex fusion were associated with increased risk of major complications, 30-day mortality, and resource use.

Less invasive and less technically demanding decompressive procedure for lumbar spinal stenosis--appropriate for general orthopaedic surgeons?

This article presents the clinical and radiological results of the modified spinous process osteotomy decompressive procedure (MSPO), which affords excellent visualisation and provides wide access for Kerrison rongeur use and angulation while minimising destruction of tissues not directly involved in the pathological process. A total of 50 patients with degenerative lumbar spinal stenosis underwent MSPO between 2002 and 2005. The minimum follow-up period was five years. Patient's walking distance ability was 85.4 m (5-180 m) preoperatively and 2,560 m (1500-8000 m) at the last follow-up. Leg pain improved in 100% of the patients and back pain improved in 89% at the last follow-up. The overall results were good to excellent in 90% of the patients, fair in 16% and all patients were satisfied with the outcome at the last follow-up. The osteotomised spinous process eventually united with the retained laminar bridge in all patients within nine months after surgery. Degenerative lumbar spinal stenosis can be adequately decompressed with less violation of the integrity of the posterior elements using MSPO. The described technique of MSPO yielded promising results with few complications. The authors believe MSPO is less technically demanding and appropriate for general orthopaedic surgeons, occasional spine surgeons and chief residents.

Predictors of outcome after decompressive lumbar surgery and instrumented posterolateral fusion

There has been no agreement among different authors on guidelines to specify the situations in which arthrodesis is justified in terms of results, risks and complications. The aim of this study was to identify preoperative predictors of outcome after decompressive lumbar surgery and instrumented posterolateral fusion. A prospective observational study design was performed on 203 consecutive patients. Potential preoperative predictors of outcome included sociodemographic factors as well as variables pertaining to the preoperative clinical situation, diagnosis, expectations and surgery. Separate multiple linear regression models were used to assess the association between selected predictors and outcome variables, defined as the improvement after 1 year on the visual analog scale (VAS) for back pain, VAS for leg pain, physical component scores (PCS) of SF-36 and Oswestry disability index (ODI). Follow-up was available for 184 patients (90.6%). Patients with higher educational level and optimistic preoperative expectations had a more favourable postoperative leg pain (VAS) and ODI. Smokers had less leg pain relief. Patients with better mental component score (emotional health) had greater ODI improvement. Less preoperative walking capacity predicted more leg pain relief. Patients with disc herniation had greater relief from back pain and more PCS and ODI improvement. More severe lumbar pain was predictive of less improvement on ODI and PCS. Age, sex, body mass index, analgesic use, surgeon, self-rated health, the number of decompressed levels and the length of fusion had no association with outcome. This study concludes that a higher educational level, optimistic expectations for improvement, the diagnosis of "disc herniation", less walking capacity and good emotional health may significantly improve clinical outcome. Smoking and more severe lumbar pain are predictors of worse results.

Defining value in spine care

Spinal disorders are extremely common, debilitating, and costly to the payer and to society as a whole. The rate and cost of various spinal treatments are increasing at an astonishing rate, but it is unclear whether the resulting quality of spinal care is improving. Rather than focusing solely on quality improvement measures or cost-saving measures, there is a recent emphasis on the value of health care. Defining the value of spine care depends on a standardized, accurate method of measuring outcomes and costs. It is important that the outcomes measured are patient centered and that both the outcomes and costs are measured over time with long-term follow-up. The purpose of this article is to review current methods for measuring outcomes and propose a means by which the value of spine care can be more clearly defined.

Improvement of back pain with operative and nonoperative treatment in adults with scoliosis

OBJECTIVE

The purpose of this study was to assess whether back pain is improved with surgical treatment compared with nonoperative management in adults with scoliosis.

METHODS

This is a retrospective review of a prospective, multicentered database of adults with spinal deformity. At the time of enrollment and follow-up, patients completed standardized questionnaires, including the Oswestry Disability Index (ODI) and Scoliosis Research Society 22 questionnaire (SRS-22), and assessment of back pain using a numeric rating scale (NRS) score, with 0 and 10 corresponding to no and maximal pain, respectively. The initial plan for surgical or nonoperative treatment was made at the time of enrollment.

RESULTS

Of 317 patients with back pain, 147 (46%) were managed surgically. Compared with patients managed nonoperatively, operative patients had higher baseline mean NRS scores for back pain (6.3 versus 4.8; P < 0.001), higher mean ODI scores (35 versus 26; P < 0.001), and lower mean SRS-22 scores (3.1 versus 3.4; P < 0.001). At the time of the 2-year follow-up evaluation, nonoperatively managed patients did not have significant change in the NRS score for back pain (P = 0.9), ODI (P = 0.7), or SRS-22 (P = 0.9). In contrast, at the 2-year follow-up evaluation, surgically treated patients had significant improvement in the mean NRS score for back pain (6.3 to 2.6; P < 0.001), ODI score (35 to 20; P < 0.001), and SRS-22 score (3.1 to 3.8; P < 0.001). Compared with nonoperatively treated patients, at the time of the 2-year follow-up evaluation, operatively treated patients had a lower NRS score for back pain (P < 0.001) and ODI (P = 0.001), and higher SRS-22 (P < 0.001).

CONCLUSIONS

Despite having started with significantly greater back pain and disability and worse health status, surgically treated patients had significantly less back pain and disability and improved health status compared with nonoperatively treated patients at the time of the 2-year follow-up evaluation. Compared with nonoperative treatment, surgery can offer significant improvement of back pain for adults with scoliosis.

Impact of instrumentation in lumbar spinal fusion in elderly patients: 71 patients followed for 2-7 years

BACKGROUND AND PURPOSE

An increasing number of lumbar fusions are performed using allograft to avoid donor-site pain. In elderly patients, fusion potential is reduced and the patient may need supplementary stability to achieve a solid fusion if allograft is used. We investigated the effect of instrumentation in lumbar spinal fusion performed with fresh frozen allograft in elderly patients.

METHODS

94 patients, mean age 70 (60-88) years, who underwent posterolateral spinal fusion either non-instrumented (51 patients) or instrumented (43 patients) were followed for 2-7 years. Functional outcome was assessed with the Dallas pain questionnaire (DPQ), the low back pain rating scale pain index (LBPRS), and SF-36. Fusion was assessed using plain radiographs.

RESULTS

Instrumented patients had statistically significantly better outcome scores in 6 of 7 parameters. Fusion rate was higher in the instrumented group (81% vs. 68%, p = 0.1). Solid fusion was associated with a better functional outcome at follow-up (significant in 2 of 7 parameters). 15 patients (6 in the non-instrumented group and 9 in the instrumented group) had repeated lumbar surgery after their initial fusion procedure. Functional outcome was poorer in the group with additional spine surgeries (significant in 4 of 7 parameters).

INTERPRETATION

Superior outcomes after lumbar spinal fusion in elderly patients can be achieved by use of instrumentation in selected patients. Outcome was better in patients in which a solid fusion was obtained. Instrumentation was associated with a larger number of additional surgeries, which resulted in a lesser degree of improvement. Instrumentation should not be discarded just because of the age of the patient.

Surgical treatment for lumbar lateral recess stenosis with the full-endoscopic interlaminar approach versus conventional microsurgical technique: a prospective, randomized, controlled study

OBJECT

Extensive decompression with laminectomy where appropriate is often still described as the method of choice in surgery for lateral recess stenosis. Nonetheless, tissue-sparing procedures are becoming more common. Endoscopic techniques have become the standard in many areas because of the advantages they offer in surgical technique and in rehabilitation. Transforaminal and interlaminar access provide 2 full-endoscopic (FE) techniques for lumbar spine surgery. The goal of this prospective randomized controlled study was to compare the surgical results for the FE technique via the interlaminar approach with those of the conventional microsurgical technique in patients with degenerative lateral recess stenosis.

METHODS

A total of 161 patients with FE or microsurgical decompression underwent follow-up for 2 years. In addition to general and specific parameters, the following measuring instruments were used: visual analog scale, German version of the North American Spine Society instrument, and the Oswestry low-back pain disability questionnaire.

RESULTS

The results show that 74.5% of patients reported no longer having leg pain, and 20.5% had only occasional pain. The clinical results were the same in both groups. The rate of complications and revisions was significantly reduced in the FE group. The FE techniques brought advantages in the following areas: operation, complications, traumatization, and rehabilitation.

CONCLUSIONS

The clinical results of the FE interlaminar technique are equal to those of the microsurgical technique. At the same time, there are advantages in the operation technique, such as reduced traumatization. The FE interlaminar spinal decompression procedure is a sufficient and safe supplement and alternative to microsurgical procedures.

Degenerative lumbar stenosis: update

We present a literature review of the diagnosis and treatment of acquired lumbar spinal stenosis (LS), with a brief description of new surgical techniques. LS is the most common cause of spinal surgery in individuals older than 65 years of age. Neurogenic claudication and radiculopathy result from compression of the cauda equina and lumbosacral nerve roots by degenerated spinal elements. Surgical decompression is a well established treatment for patients with refractory, or moderate to severe clinical symptoms. However, the variety of surgical options is vast. New techniques have been developed with the goal of increasing long term functional outcomes. In this article we review lumbar decompression and fusion as treatment options for LS but also present other recent developments. Prospective long term studies are necessary to know which procedures would result in optimal patient outcome.

The impact of economic evaluation on quality management in spine surgery

Health care expenditures are substantially increasing within the last two decades prompting the imperative need for economic evaluations in health care. Historically, economic evaluations in health care have been carried out by four approaches: (1) the human-capital approach (HCA), (2) cost-effectiveness analysis (CEA), (3) cost-utility analysis (CUA) and (4) cost-benefit analysis (CBA). While the HCA cannot be recommended because of methodological shortcomings, CEA and CUA have been used frequently in healthcare. In CEA, costs are measured in monetary terms and health effects are measured in a non-monetary unit, e.g. number of successfully treated patients. In an attempt to develop an effectiveness measure that incorporates effects on both quantity and quality of life, so-called Quality Adjusted Life Years (QUALYs) were introduced. Contingent valuation surveys are used in cost-benefit analyses (CBA) to elicit the consumer's monetary valuations for program benefits by applying the willingness-to-pay approach. A distinguished feature of CBA is that costs and benefits are expressed in the same units of value, i.e. money. Only recently, economic evaluations have started to explore various spinal interventions particularly the very expensive fusion operations. While most of the studies used CEA or CUA approaches, CBAs are still rare. Most studies fail to show that sophisticated spinal interventions are more cost-effective than conventional treatments. In spite of the lack of therapeutic or cost-effectiveness for most spinal surgeries, there is rapidly growing spinal implant market demonstrating market imperfection and information asymmetry. A change can only be anticipated when physicians start to focus on the improvement of health care quality as documented by outcome research and economic evaluations of cost-effectiveness and net benefits.

Surgical treatment of spinal stenosis with and without degenerative spondylolisthesis: cost-effectiveness after 2 years

BACKGROUND

The SPORT (Spine Patient Outcomes Research Trial) reported favorable surgery outcomes over 2 years among patients with stenosis with and without degenerative spondylolisthesis, but the economic value of these surgeries is uncertain.

OBJECTIVE

To assess the short-term cost-effectiveness of spine surgery relative to nonoperative care for stenosis alone and for stenosis with spondylolisthesis.

DESIGN

Prospective cohort study.

DATA SOURCES

Resource utilization, productivity, and EuroQol EQ-5D score measured at 6 weeks and at 3, 6, 12, and 24 months after treatment among SPORT participants.

TARGET POPULATION

Patients with image-confirmed spinal stenosis, with and without degenerative spondylolisthesis.

TIME HORIZON

2 years.

PERSPECTIVE

Societal.

INTERVENTION

Nonoperative care or surgery (primarily decompressive laminectomy for stenosis and decompressive laminectomy with fusion for stenosis associated with degenerative spondylolisthesis).

OUTCOME MEASURES

Cost per quality-adjusted life-year (QALY) gained.

RESULTS OF BASE-CASE ANALYSIS

Among 634 patients with stenosis, 394 (62%) had surgery, most often decompressive laminectomy (320 of 394 [81%]). Stenosis surgeries improved health to a greater extent than nonoperative care (QALY gain, 0.17 [95% CI, 0.12 to 0.22]) at a cost of $77,600 (CI, $49,600 to $120,000) per QALY gained. Among 601 patients with degenerative spondylolisthesis, 368 (61%) had surgery, most including fusion (344 of 368 [93%]) and most with instrumentation (269 of 344 [78%]). Degenerative spondylolisthesis surgeries significantly improved health versus nonoperative care (QALY gain, 0.23 [CI, 0.19 to 0.27]), at a cost of $115,600 (CI, $90,800 to $144,900) per QALY gained. RESULT OF SENSITIVITY ANALYSIS: Surgery cost markedly affected the value of surgery.

LIMITATION

The study used self-reported utilization data, 2-year time horizon, and as-treated analysis to address treatment nonadherence among randomly assigned participants.

CONCLUSION

The economic value of spinal stenosis surgery at 2 years compares favorably with many health interventions. Degenerative spondylolisthesis surgery is not highly cost-effective over 2 years but could show value over a longer time horizon.

Waste in the U.S. Health care system: a conceptual framework

CONTEXT

Health care costs in the United States are much higher than those in industrial countries with similar or better health system performance. Wasteful spending has many undesirable consequences that could be alleviated through waste reduction. This article proposes a conceptual framework to guide researchers and policymakers in evaluating waste, implementing waste-reduction strategies, and reducing the burden of unnecessary health care spending.

METHODS

This article divides health care waste into administrative, operational, and clinical waste and provides an overview of each. It explains how researchers have used both high-level and sector- or procedure-specific comparisons to quantify such waste, and it discusses examples and challenges in both waste measurement and waste reduction.

FINDINGS

Waste is caused by factors such as health insurance and medical uncertainties that encourage the production of inefficient and low-value services. Various efforts to reduce such waste have encountered challenges, such as the high costs of initial investment, unintended administrative complexities, and trade-offs among patients', payers', and providers' interests. While categorizing waste may help identify and measure general types and sources of waste, successful reduction strategies must integrate the administrative, operational, and clinical components of care, and proceed by identifying goals, changing systemic incentives, and making specific process improvements.

CONCLUSIONS

Classifying, identifying, and measuring waste elucidate its causes, clarify systemic goals, and specify potential health care reforms that-by improving the market for health insurance and health care-will generate incentives for better efficiency and thus ultimately decrease waste in the U.S. health care system.

Development of an index to characterize the "invasiveness" of spine surgery: validation by comparison to blood loss and operative time

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

To create and validate an index describing the extent of spine surgical intervention to allow fair comparisons of complication rates among patients treated by different surgeons, devices, or hospitals.

SUMMARY OF BACKGROUND DATA

Safety comparisons in spine surgery are limited by lack of methods that adjust for important variations in the surgical "case-mix." Among other factors, the magnitude of an operation is likely to have a substantial influence on the likelihood of complications.

METHODS

We created a spine surgery invasiveness index defined as the sum, across all vertebral levels, of 6 possible interventions on each operated vertebra: anterior decompression, anterior fusion, anterior instrumentation, posterior decompression, posterior fusion, and posterior instrumentation. We assessed the validity of this index by examining its association with blood loss and surgery duration in 1723 spine surgeries, adjusting for important factors including age, gender, body mass index, diagnosis, neurologic deficit, revision surgery, and vertebral level of surgery.

RESULTS

Blood loss increased by 11.5% and surgery duration increased by 12.8 minutes for each unit increase in the invasiveness index. The invasiveness index explained 44% of the variation in blood loss and 52% of the variation in surgery duration. For specific surgical components, blood loss increased by 9.4% and surgery duration by 11.4 minutes for each vertebral level of anterior decompression, 19.4% and 33.8 minutes for each segment of anterior instrumentation, 12.9% and 22.7 minutes for each level of posterior decompression, and 25.1% and 18.8 minutes for each segment of posterior instrumentation.

CONCLUSION

An "invasiveness" index based on the number of vertebrae decompressed, fused, or instrumented showed the expected associations with both blood loss and surgery duration. This quantitative description of surgery invasiveness may be useful to adjust for surgical variations when making safety comparisons in spine surgery.

An analysis of noninstrumented posterolateral lumbar fusions performed in predominantly geriatric patients using lamina autograft and beta tricalcium phosphate

BACKGROUND CONTEXT

The artificial bone-volume expander, beta tricalcium phosphate (B-TCP, Vitoss, OrthoVita, Malvern, PA), is increasingly used to supplement autograft in posterolateral lumbar fusions.

PURPOSE

To determine fusion rates/outcomes using B-TCP/autograft.

STUDY DESIGN/SETTING

Fusion rates and outcomes were assessed for 60 predominantly geriatric patients undergoing multilevel lumbar laminectomies and 1- to 2-level noninstrumented fusions using B-TCP/autograft.

PATIENT SAMPLE

Patients on average were 70 years old.

OUTCOME MEASURES

Odom's criteria and Short-Form 36 (SF-36) outcomes were studied 2 years postoperatively.

METHODS

Sixty patients underwent an average of 5.4-level laminectomies with 1- to 2-level noninstrumented fusions. Based on dynamic X-ray/magnetic resonance/computed tomography (CT) studies, laminectomies addressed multilevel stenosis (60 patients), ossification of the yellow ligament (46 patients), disc herniations (20 patients), or synovial cysts (8 patients), and fusions addressed degenerative spondylolisthesis (48 patients), spondylolisthesis/lysis (2 patients), or degenerative scoliosis (10 patients). The fusion mass on each side contained half of all harvested autograft combined with one to 1.5 strips of B-TCP (saturated in 10cc of bone marrow aspirate/strip). Fusion rates were documented by two independent neuroradiologists using both dynamic X-rays, and thin-cut CT (2-dimensional/3-dimensional CT) studies obtained up to 2 years postoperatively. Odom's criteria and SF-36 outcomes were assessed over the same interval.

RESULTS

Pseudarthrosis was documented in nine (15%) patients. Two years postoperatively, Odom's criteria revealed 28 excellent, 23 good, 5 fair, and 4 poor results, whereas SF-36 data revealed improvement on 6 of 8 Health Scales in all patients.

CONCLUSIONS

A 15% pseudarthrosis rate followed multilevel laminectomy and 1- to 2-level noninstrumented posterolateral fusion using lamina autograft/B-TCP.

Minimum four-year follow-up of spinal stenosis with degenerative spondylolisthesis treated with decompression and dynamic stabilization

STUDY DESIGN

Prospective clinical study.

OBJECTIVE

To test whether posterior dynamic stabilization in situ with Dynesys (Zimmer Spine, Minneapolis, MN) can maintain enough stability to prevent progression of spondylolisthesis in long-term follow-up.

SUMMARY OF BACKGROUND DATA

In spinal stenosis with degenerative spondylolisthesis, decompression and fusion are widely recommended. However, drawbacks of fusion remain length of surgery, blood loss, possible adjacent segment disease, errant instrumentation, nonunion, and pain at the bone donor site. The Dynesys system was introduced to stabilize the spine without adding bone graft for fusion. Excellent 2 years results have been reported.

METHODS

Twenty-six consecutive patients (mean age, 71 years) with symptomatic lumbar spinal stenosis and degenerative spondylolisthesis underwent interlaminar decompression and stabilization with Dynesys. Patients were evaluated clinically and radiologically after a minimum follow-up of 4 years.

RESULTS

Nineteen of 26 patients could be evaluated with a mean follow-up of 52 months (range, 48-57 months). Pain on VAS and walking distance improved significantly (P < 0.001) at 2 years and remained unchanged at 4 years follow-up. Radiographically, spondylolisthesis did not progress and the motion segments remained stable, even in the 3 patients who showed slight screw-loosening at 2 and 4 years follow-up. One patient showed screw breakage with low back pain and motion at the instrumented level in flexion/extension views. At 4 years follow-up, 47% of the patients showed some degeneration at adjacent levels. Overall, patient satisfaction remained high as 95% would undergo the same procedure again.

CONCLUSION

In elderly patients with spinal stenosis and degenerative spondylolisthesis, decompression and dynamic stabilization lead to excellent clinical and radiologic results. It maintains enough stability to prevent progression of spondylolisthesis. Because no bone grafting is necessary, donor site morbidity, which is one of the main drawbacks of fusion is eliminated. However, the degenerative disease still is progressive and degeneration at adjacent motion segments remains a problem.

Fusion rates and SF-36 outcomes after multilevel laminectomy and noninstrumented lumbar fusions in a predominantly geriatric population

STUDY DESIGN

This study prospectively analyzed posterolateral fusion rates and Short-Form 36 (SF-36) outcomes after multilevel lumbar laminectomies and noninstrumented fusions.

OBJECTIVE

SF-36 outcomes and posterolateral fusion rates were assessed.

SUMMARY OF BACKGROUND DATA

Technologically advanced and expensive instrumentation techniques and fusion adjuncts (ie, bone morphogenetic protein) may not be necessary to achieve lumbar fusion in the geriatric population. Rather, noninstrumented fusions using lamina autograft and a bone volume expander may suffice.

METHODS

Seventy-five patients averaging 69 years of age (49 females, 26 males) underwent average 4.9 level lumbar laminectomies with average 2.0 level noninstrumented posterolateral fusions using lamina autograft (average 30 cm) supplemented with demineralized bone matrix (average 30 cm) in a 50:50 mix. Two independent radiologists separately evaluated both 2-dimensional computed tomography (2D-CT) and dynamic x-ray data 3, 4.5, 6, and up to 12 months postoperatively; patients had to demonstrate fusion on both studies. Outcomes were assessed using the SF-36 questionnaire (preoperatively) 3, 6, 12, and 24 months postoperatively. Patients were followed an average of 3.3 years (minimum 2 y).

RESULTS

Thirteen (17.3%) patients demonstrated pseudarthrosis as they had not fused on dynamic x-ray and/or 2D-CT studies an average of 5.6 months postoperatively. One patient required a secondary fusion. One and 2 years postoperatively, patients demonstrated nearly identical maximal improvement on 6 SF-36 Health Scales, but showed no real changes on General Health and Mental Health scales.

CONCLUSIONS

Seventy-five predominantly geriatric patients underwent multilevel laminectomies with noninstrumented fusions using lamina autograft combined with a bone volume expander. Thirteen patients (17.3%) demonstrated pseudarthrosis on the basis of both dynamic x-ray and 2D-CT criteria; 1 patient required a second instrumented fusion. Moderate pseudarthrosis rates, a low reoperation rate, and satisfactory SF-36 outcomes were achieved using noninstrumented posterolateral fusions in a predominantly geriatric population.

Assessment of health-related quality of life after surgical treatment of focal symptomatic spinal stenosis compared with osteoarthritis of the hip or knee

BACKGROUND CONTEXT

In the last decade, the number of patients undergoing surgical treatment for lumbar spinal stenosis (LSS), particularly instrumented fusions, has significantly increased. The surgical procedures for LSS represent a significant cost to the health-care system and are a priority focus for most governments, insurers, hospital administrators, and spine care physicians.

PURPOSE

The purpose of this study was to directly compare the relative improvement in self-reported quality of life after surgical intervention for matched groups of patients with primary hip or knee osteoarthritis (H-OA/K-OA) and focal lumbar spinal stenosis (FLSS).

STUDY DESIGN/SETTING

Observational cohort study of prospectively collected outcomes.

PATIENT SAMPLE

Patients, following elective primary one- to two-level spinal decompression (n=90) with (n=28/90) or without fusion for FLSS, were compared with a matched (age, sex, and time of surgery) cohort of patients who had undergone elective total hip (n=90) or total knee (n=90) arthroplasty (total joint arthroplasty [TJA]) for primary osteoarthritis.

OUTCOME MEASURES

Medical Outcomes Study Short Form-36 (SF-36).

METHODS

Patents were obtained for prospective outcomes databases (TJA and spine). Inclusion and exclusion criteria were independently applied, and matching was performed in a blinded fashion. The primary outcome measure was the relative change between preoperative and 2-year postoperative SF-36 questionnaires. Data were analyzed with the t test and repeated measures analysis of variance (ANOVA).

RESULTS

The three groups (FLSS/H-OA/K-OA) were equally matched with respect to mean age (64/63/65 years), sex (female/male, 51/39 for all groups), body mass index (BMI) (27/24/27), and American Society of Anesthesiologists (ASA) physical status (2/2/2). Comparison of preoperative SF-36 physical component summary (PCS) scores and mental component summary (MCS) scores between groups showed no statistical difference (PCS: FLSS=32.0, H-OA=30.2, K-OA=31.3 [p=.32, ANOVA]/MCS: FLSS=43.5, H-OA=45.0, K-OA=46.2 [p=.25, ANOVA]). Postoperatively, PCS improved significantly for all groups (1 year-PCS: FLSS=39.6, H-OA=44.5, K-OA=38.5 [p<.0001 for all groups]; 2 years-PCS: FLSS=38.6, H-OA=43.2, K-OA=37.1 [p<.0001 for all groups]). At both 1- and 2-year follow-ups, the PCS improvement between groups was greater for the H-OA group compared with the FLSS (p=.0037, p=.0073) and K-OA (p=.00016, p=.00053) groups. At the 1-year follow-up, MCS did not significantly increase for any group; however, 2 years postoperatively, MCS improved significantly for the FLSS and H-OA groups (2 years-MCS: FLSS=50.3, H-OA=50.9, K-OA=44.8 [p=.00021, p=.00079, p=.35]). At the 1-year follow-up, there was no statistical difference in MCS improvement between groups (p=.45, ANOVA). Two years postoperatively, the MCS for both the FLSS and H-OA groups was significantly greater than that for the K-OA group (p=.0014, p=.00055).

CONCLUSIONS

The results of this study show that surgical intervention for FLSS can obtain and maintain improvement in self-reported quality of life comparable to that of total hip and knee arthroplasty. This study provides data to support the need for prospective cost-effectiveness studies for the surgical management of appropriately selected patients suffering from FLSS.

Long-term outcomes of two different decompressive techniques for lumbar spinal stenosis

STUDY DESIGN

A prospective study to evaluate the outcomes of 2 different decompressive techniques for lumbar spinal stenosis.

OBJECTIVE

To explore a more effective and less invasive decompression technique without instrument and fusion for lumbar spinal stenosis.

SUMMARY OF BACKGROUND DATA

The traditional surgical decompression of spinal stenosis involves laminectomy or unilateral laminotomy. Even in unilateral laminotomy cases, 85.3% had an excellent-to-fair operative result, and the incidence of complications was 9.8%. Although the addition of instrumentation does not increase the complication rate, but compared to the efficiency, the higher costs was controversial. Minimal invasion and destabilization are recommended.

METHODS

This prospective study included 152 consecutive patients, sequentially divided into 2 groups, underwent Windows technique (group A) and decompressive laminectomy (group B) by 2 groups of surgeons.

RESULTS

The evaluation of the back pain, leg pain, walking tolerance, and neurologic recovery were performed before surgery and after surgery. In group A, at the final evaluation, the overall results were good to excellent in 89% (68/76) of the patients, fair 11% (8/76), and poor 0%. In group B, at the final evaluation, the overall results were good to excellent in 63% (48/76) of the patients, fair 30% (23/76), and poor 7% (5/76).

CONCLUSION

Degenerative spinal stenosis can be decompressed adequately with preserving the posterior elements. The "Windows technique" laminoforaminotomy, which obtained satisfactory long-term outcomes with few complications and low cost, can be a standard procedure for the surgical treatment of the degenerative spinal stenosis even with slight congenital spinal stenosis.

Examining heterogeneity in meta-analysis: comparing results of randomized trials and nonrandomized studies of interventions for low back pain

STUDY DESIGN

Literature review.

OBJECTIVE

To assess the influence of various factors in statistical heterogeneity of meta-analyses of interventions for low back pain. One of these factors was study design: randomized controlled trial (RCT) versus nonrandomized study (NRS).

SUMMARY OF BACKGROUND DATA

The presence of statistical heterogeneity poses a challenge to the conduct and interpretation of meta-analyses.

METHODS

We searched MEDLINE, EMBASE, and The Cochrane Library up to May 2005 for comparative studies of interventions for low back pain. The interventions with the highest number of NRSs were selected. All NRSs and RCTs of the same interventions were combined using meta-analysis. Subgroup analyses and meta-regression were performed according to study design and other factors that were selected by a panel of 20 experts.

RESULTS

NRSs frequently either agree with RCTs or underestimate the effects compared with RCTs. The interventions and the respective factors that explained statistical heterogeneity were a) surgery versus conservative treatments (17 NRSs and 8 RCTs): study design (odds ratio, OR: 1.56 and 4.69 for nonrandomized and randomized studies, respectively), pain duration (OR: 1.75 and 3.55 for chronic and acute, respectively), and involvement of workers' compensation (OR: 1.85 and 5.07, with and without, respectively); b) surgery with fusion versus surgery without fusion (17 NRSs and 3 RCTs): spondylolisthesis (OR: 2.15 and 1.22, with and without, respectively); c) Instrumented fusion versus noninstrumented fusion (15 NRSs and 8 RCTs): previous surgery (OR: 2.89 and 1.36, with and without, respectively) and levels fused (OR: 1.50 and 2.98, single and multilevel, respectively).

CONCLUSION

Comparisons between RCTs and NRSs may be influenced by various factors, including study design. However, other factors were more powerful explanatory variables than study design. These factors included pain duration, involvement of workers' compensation, presence of spondylolisthesis, previous surgery, and levels fused.

Degenerative lumbar spinal stenosis: analysis of results in a series of 374 patients treated with unilateral laminotomy for bilateral microdecompression

Object

Surgical decompression is the recommended treatment in patients with moderate to severe degenerative lumbar spinal stenosis (DLSS) in whom symptoms do not respond to conservative therapy. Multilevel disease, poor patient health, and advanced age are generally considered predictors of a poor outcome after surgery, essentially because of a surgical technique that has always been considered invasive and prone to causing postoperative instability. The authors present a minimally invasive surgical technique performed using a unilateral approach for lumbar decompression.

Methods

A retrospective study was conducted of data obtained in a consecutive series of 473 patients treated with unilateral microdecompression for DLSS over a 5-year period (2000–2004). Clinical outcome was measured using the Prolo Economic and Functional Scale and the visual analog scale (VAS). Radiological follow-up included dynamic x-ray films of the lumbar spine and, in some cases, computed tomography scans.

Results

Follow-up was completed in 374 (79.1%) of 473 patients—183 men and 191 women. A total of 520 levels were decompressed: 285 patients (76.2%) presented with single-level stenosis, 86 (22.9%) with two-level stenosis, and three (0.9%) with three-level stenosis.

Three hundred twenty-nine patients (87.9%) experienced a clinical benefit, which was defined as neurological improvement in VAS and Prolo Scale scores. Only three patients (0.8%) reported suffering segmental instability at a treated level, but none required surgical stabilization, and all were successfully treated conservatively.

Conclusions

Evaluation of the results indicates that unilateral microdecompression of the lumbar spine offers a significant improvement for patients with DLSS, with a lower rate of complications.

Bilateral interlaminar fenestration and unroofing for the decompression of nerve roots by using a unilateral approach in lumbar canal stenosis

BACKGROUND

Conventional laminectomy is a simple procedure that provides adequate decompression in cases of lumbar spinal canal stenosis. However, with this surgical modality, important posterior osteoligamentous elements necessary for spinal stability are lost; and it is often accompanied by damage to the facet joint. Bilateral interlaminar fenestration and unroofing of the intervertebral foramen to achieve decompression of the nerve roots by using a unilateral microsurgical approach in lumbar spinal canal stenosis are less invasive compared with conventional laminectomy.

METHODS

We carried out bilateral interlaminar fenestration and unroofing of the intervertebral foramen to decompress the stenosed nerve roots under a microscope by using a unilateral approach. In particular, we performed the decompression of the contralateral nerve root with this surgical method by using a Caspar retractor. Surgery was performed on 47 patients (18 women and 29 men; 29-85 years; median age, 62 years). All cases were with single-level lumbar spinal canal stenosis and bilateral radiculopathy.

RESULTS

The mean preoperative NCOS was 29.8 (range, 8-48). The mean NCOS after a postoperative period of 3 months was 79.9 (range, 32-100). After a postoperative period of 2 years, the mean NCOS increased to 83.2 (range, 32-100). The satisfaction measures indicated that the procedure was "very successful" in 45 cases, providing "almost complete relief"; "fairly successful" in one case, providing "a good deal of relief"; and "not very successful" in another case, affording "only a little relief."

CONCLUSIONS

This unilateral, minimally invasive decompression provided satisfactory results.

Construct validity of the physical function scale of the Swiss Spinal Stenosis Questionnaire for the measurement of walking capacity

STUDY DESIGN

Measurement (validity) study using data from a prospective longitudinal study of lumbar spinal stenosis.

OBJECTIVE

Provide convergent and divergent validity evidence for the use of the Physical Function Scale of the Swiss Spinal Stenosis Questionnaire for the measurement of walking capacity in persons with lumbar spinal stenosis. We were also interested in the association between the Physical Function Scale and the Oswestry Disability Index (ODI).

SUMMARY OF BACKGROUND DATA

The Physical Function Scale has been used to assess walking capacity in persons with lumbar spinal stenosis; however, there have been limited studies investigating its psychometric properties. No validity studies have compared the Physical Function Scale and the ODI head to head.

METHODS

The Physical Function Scale was correlated with the ODI, Health Utilities Index, Centres for Epidemiologic Studies Depression Scale, Medical Outcomes Survey Social Support Scale, and an additional item from the Oxford Claudication Score.

RESULTS

As hypothesized, the Physical Function Scale was correlated highly with those instruments and items intended to measure walking capacity and minimally with those instruments intended to measure different constructs. The correlation between the Physical Function Scale and the ODI was r = 0.719.

CONCLUSION

Results support construct validity of the Physical Function Scale for the measurement of walking in an lumbar spinal stenosis population. However, it cannot be ascertained from the current study that the construct being measured is, indeed, walking capacity. Further research is warranted to investigate criterion validity evidence for the use of the Physical Function Scale in the measurement of walking capacity in lumbar spinal stenosis, by examining the relationships between self-report and observational measures of walking.

Minimally invasive operative management for lumbar spinal stenosis: overview of early and long-term outcomes

Standard open posterior decompression is well established and familiar to virtually all spine surgeons. However, this traditional surgical treatment of lumbar spinal stenosis (LSS) is often associated with significant postoperative pain, disability, and dysfunction. This article reviews the use of a minimally invasive microendoscopic approach for bilateral decompression of lumbar stenosis by way of a unilateral approach. This technique has been shown to provide symptomatic relief equivalent to that of open discectomy, with significant reductions in operative blood loss, postoperative pain, hospital stay, and narcotic usage. Furthermore, the article explains the rationale, indications, and surgical techniques for minimally-invasive LSS surgery and presents the authors' 4-year outcomes data.

Foraminal stenosis and single-level degenerative disc disease: a randomized controlled trial comparing decompression with decompression and instrumented fusion

STUDY DESIGN

A randomized controlled trial with 5-year outcome data.

OBJECTIVE

To compare clinical outcomes following spinal decompression (Group 1) with those following decompression and instrumented posterolateral fusion (Group 2) and decompression and instrumented posterolateral fusion plus transforaminal interbody fusion (TLIF) (Group 3).

SUMMARY OF BACKGROUND DATA

Decompression is frequently advocated for the relief of nerve root stenosis in the presence of degenerate disc disease. It is uncertain if spinal fusion is also necessary.

MATERIALS AND METHODS

Following completion of a standardized physiotherapy program, 44 patients with single-level disc disease were randomly assigned to 1 of 3 surgical groups. In those patients undergoing instrumentation, segmental pedicle screw fixation was used to stabilize the spine. Titanium interbody cages filled with autologous bone were inserted into patients in Group 3. Spinal disability, quality of life, and pain were assessed before surgery, and then at 1, 2, and 5 years by an independent researcher.

RESULTS

At 2 years, 82% of the patients were pain free or moderately improved. Disability (Low Back Outcome Score and Roland Morris index) were both better in Group 1, but only Low Back Outcome Score was better in Group 2 (P < 0.05). By 5 years, although patients in all 3 groups showed some improvements in all the ratings used (Low Back Outcome Score, SF-36 Physical Functioning, and Roland Morris score), only Group 1 patients showed significant changes in all 3 outcomes (P < 0.05). There was no difference in any score between groups (P > 0.05). Two had secondary surgery for adjacent level stenosis (Group 2 and 3). One patient (Group 1) underwent subsequent lateral mass fusion for chronic pain. No patient required revision surgery for instrumentation failure, cage displacement, or pseudarthrosis. Evidence of at least unilateral lateral mass bone graft incorporation was evident in 95% of Groups 2 and 3.

CONCLUSIONS

The results are encouraging in that almost all patients had improved by 5 years. However, it is a concern that no significant additional benefit has been noted from the more complex surgery. This suggests that patients are optimally treated by decompression alone, with the proviso that further operations may be required.

Split-spinous process laminotomy and discectomy for degenerative lumbar spinal stenosis: a preliminary report

OBJECT

The authors evaluated a new minimally invasive spinal surgery technique to correct degenerative lumbar spinal stenosis involving a split-spinous process laminotomy and discectomy (also known as the "Marmot operation").

METHODS

This prospective study randomized 70 patients with lumbar stenosis to undergo either a Marmot operation (40 patients), or a conventional laminectomy (30 patients), with or without discectomy. Spinal anteroposterior diameter, cross-sectional area, lateral recess distance, spinal stability, postoperative back pain, functional outcomes, and muscular trauma were evaluated. The follow up ranged from 10 to 18 months, with a mean of 15.1 months for the Marmot operation group and 14.8 months for the conventional laminectomy group. Compared with patients in the conventional laminectomy group, patients who received a Marmot operation had a shorter mean postoperative duration until ambulation without assistance, a reduced mean duration of hospital stay, a lower mean creatine phosphokinase-muscular-type isoenzyme level, a lower visual analog scale score for back pain at 1-year follow up, and a better recovery rate. These patients also had a longer mean duration of operative time and a greater mean blood loss compared with the conventional group. Satisfactory neurological decompression and symptom relief were achieved in 93% of these patients. Most of the patients (66%) in this group needed discectomy for decompression. The postoperative mean lateral recess width, spinal anteroposterior diameter, and cross-sectional area were all significantly increased. There was no evidence of spinal instability in any patient. One patient with insufficient lateral recess decompression and recurrent disc herniation needed additional conventional laminectomy and discectomy, and one patient with mild superficial wound infection was successfully treated with antibiotics and frequent dressing changes.

CONCLUSIONS

A Marmot operation may provide effective spinal decompression. Although this method requires more operative time than a conventional method, it may involve only minimal muscular trauma, spinal stability maintenance, and early mobilization; shorten the duration of hospital stay; reduce postoperative back pain; and provide satisfactory neurological and functional outcomes.

Depression is associated with poorer outcome of lumbar spinal stenosis surgery

The objective of this observational prospective study was to investigate the effect of depression on short-term outcome after lumbar spinal stenosis (LSS) surgery. Surgery was performed on 99 patients with clinically and radiologically defined LSS, representing ordinary LSS patients treated at the secondary care level. They completed questionnaires before surgery and 3 months postoperatively. Depression was assessed with the 21-item Beck Depression Inventory (BDI). Physical functioning and pain were assessed with Oswestry disability index, Stucki Questionnaire, self-reported walking ability, visual analogue scale (VAS) and pain drawing. Preoperatively, 20% of the patients had depression. In logistic regression analyses, significant associations were seen between preoperative depression and postoperative high Oswestry disability and Stucki severity scores and high intensity of pain (VAS score). In subsequent analyses, the patients with continuous depression, measured with BDI (60% of the patients who had preoperative depression), showed fewer improvements in symptom severity, disability score, pain intensity and walking capacity than the patients who did not experience depression at any phase. In those patients who recovered from depression, according to BDI-scores (35% of the patients with preoperative depression), the postoperative improvement was rather similar to the improvement seen in the normal mood group. In the surgical treatment of LSS, we recommend that the clinical practice should include an assessment of depression.

A prospective randomized study of unilateral versus bilateral instrumented posterolateral lumbar fusion in degenerative spondylolisthesis

STUDY DESIGN

Prospective randomized study on 82 patients with degenerative lumbar spondylolisthesis, having undergone posterolateral fusion with bilateral or unilateral instrumentation.

OBJECTIVE

To determine the effectiveness of unilateral pedicle instrumentation in clinical outcome and rate of union in comparison with the classic bilateral system.

SUMMARY OF BACKGROUND DATA

Instrumentation has proved to have advantages and disadvantages related to its rigidity. The use of less rigid systems applied to posterior lumbar fusions proved promising according to the results achieved in both experimental and clinical field.

METHODS

Eighty-two patients were randomized into 2 groups: Group 1 (n = 42) had had bilateral instrumentation, and Group 2 (n = 40) had only had unilateral instrumentation. One case from Group 1, L3-S1 dropped out; only fusions of 1 or 2 levels remained in the study. Length of time spent on operating, blood loss, blood transfusion, hospital stay, complications, clinical results measured by SF-36v2, and radiologic assessment of union and of loss of height of adjacent discs were analyzed and compared by means of chi2 test, t test, and Fisher exact test.

RESULTS

Statistically, there was no significant difference between the 2 groups in relation to demographics, blood loss, need of transfusion, hospital stay, complications, clinical results, rate of union, and effect on adjacent discs. The operating time needed for Group 2 was significantly shorter in than the time needed for Group 1 (P < 0.001). In Group 1, 3 of 186 screws violated the pedicle cortex requiring reoperation because root irritation versus no complication on a total of 90 screws in Group 2.

CONCLUSION

Unilateral instrumentation used for the treatment of degenerative lumbar spondylolisthesis is as effective as bilateral instrumentation when performed in addition to 1- or 2-level posterolateral fusion. The cost of this method is lower, saves time, and reduces possible risk inserting screws in only one side.

Recalibrage moins invasif des sténoses canalaires lombaires. À propos de 35 patients opérés en utilisant un système tubulaire de rétraction musculaire

BACKGROUND

The purpose of this study was to evaluate retrospectively the indications, surgical technique, and postoperative findings in a series of 35 patients presenting lumbar canal stenosis due to osteoarthritic degeneration who underwent surgery using a tubular system for muscle retraction.

METHODS

This retrospective analysis included 35 patients, 28 with lumbar canal stenosis on a single level and seven with stenosis on two levels. On the stress images, 8 of these 35 patients presented stable degenerative spondylolisthesis. The surgical technique consisted in using a tubular system for muscle retraction. This enabled access for magnification and microsurgery of the canal, which was opened via an interlaminal approach. Concentric endocanal treatment was thus achieved without laminectomy. The same surgeon performed these 35 operations. The following variables were noted: patient age, level of canal narrowing, initial symptoms, duration of the operation, postoperative pain, use of analgesics, duration of hospital stay, clinical outcome at one and six months.

RESULTS

The postoperative period (mean postoperative stay 2.5 days) was generally uneventful with little pain (mean VAS 0.8). This can be explained by the absence of invasive dissection. Disinsertion of the paravertebral muscles and use of elevators can induce muscle ischemia. The spine is not destabilized since laminectomy is avoided. The six-month outcome showed relief of the initial symptom for 84% of patients. There were two dural breaches with no clinical impact and one patient required revision surgery because of destabilization of a degenerative spondylolisthesis. One other patient also required revision for complementary laminectomy.

CONCLUSION

The short-, mid-, and long-term results of spinal canal recalibration using a less invasive approach to lumbar canal stenosis via a tubular system for muscle retraction has provided encouraging results in terms of symptom relief. The early postoperative period is short and uneventful allowing earlier resumption of daily activities. This technique reduces the cost of hospitalization and drugs and is adapted for geriatric patients. The long-term outcome with this technique should be assessed in terms of spinal stability after recalibration.

Risk factors for the development of perioperative complications in elderly patients undergoing lumbar decompression and arthrodesis for spinal stenosis: an analysis of 166 patients

STUDY DESIGN

Retrospective review.

OBJECTIVE

To quantify and describe perioperative complication rates in a large series of well-matched elderly patients who underwent lumbar decompression and arthrodesis.

SUMMARY OF BACKGROUND DATA

Posterior lumbar decompression and fusion is frequently performed to treat lumbar stenosis with instability. An increasing number of elderly patients are undergoing operative treatment for degenerative lumbar disease. The reported morbidity of performing decompression and arthrodesis in this population varies widely in the literature, with recent reports showing a high rate of major complications.

METHODS

A total of 166 patients age 65 or older that underwent primary posterior lumbar decompression and fusion with (group 1; n = 75) or without (group 2; n = 91) instrumentation were included. Hospital records were reviewed for the occurrence of any complications (major and minor), the need for transfusion, estimated length of stay, and disposition at discharge. Logistic regression (with the presence/absence of major complications as the dependent variable) was used to identify risk factors for the occurrence of a complication.

RESULTS

Five major complications (3%) occurred (group 1, 1; group 2, 4). Minor complications developed in 30.7% of group 1 and 31.9% of group 2. There were no deaths, and only one perioperative complication was attributable to the use of instrumentation. Decompression/fusion of 4 or more segments was significantly associated with the occurrence of a major complication. Advanced age, the presence of medical comorbidities, or the use of instrumentation did not increase the rate of major or minor complications. The occurrence of either a major or minor complication prolonged hospital stay.

CONCLUSIONS

Posterior lumbar decompression and fusion can be safely performed in elderly patients, with a low rate of major complications. The addition of instrumentation does not increase the complication rate. These results differ from those previously reported in the literature, which describe a significantly higher rate of complications in this age group, with a prolonged rate of hospitalization.

A novel method for the quantitative evaluation of lumbar spinal stenosis

STUDY DESIGN

A retrospective study of computed tomography (CT) myelographic images in patients with degenerative lumbar spinal stenosis (LSS).

OBJECTIVES

To introduce a new technique for the quantitative evaluation of LSS.

BACKGROUND

Advances in hardware and software technology now permit inexpensive digitalization of radiological images, and enable methodologies for quantifying space available for neural elements in spinal canal. However, a valid method with quantitative evaluation of spinal stenosis in living patients has not been developed yet.

METHODS AND MATERIALS

Preoperative CT myelographic scans of 50 patients with degenerative LSS were collected for retrospective investigation. The patients subsequently underwent lumbar decompressive surgery. They included scans from thoracic vertebra 12 (T12) to sacrum (S1), in which each segment was scanned through both the vertebral body and disk. All CT scan films were digitized using a high-resolution digital camera. ImageTool software was used to measure three parameters: cross-sectional area of dural sac at disk level (A), cross-sectional area of spinal canal at midpedicular level (B), and cross-sectional area of vertebral body (C). The dural sac canal ratio (DSCR) was calculated as A/B x 100%. Low DSCR implied severe dural sac compression with a high degree of stenosis. The spinal canal vertebral ratio (CVR) was also calculated as B/C x 100%. Low CVR implied a low baseline of canal capacity for neural elements. They were calculated from T12 to S1.

RESULTS

The study consisted of 26 male and 24 female patients, with an average age of 68.4 (35-97) years. A total of 295 segments were evaluated, of which 118 (40%) were surgically decompressed. There were wide ranges of canal cross-sectional areas (140-475 mm(2)) and dural sac cross-sectional area (54-435 mm(2)). Male patients had a slightly larger canal cross-sectional area than female patients at each level. The mean CVR was found decreased from T12 (26.1%) to L4 (18.3%). This was higher in female than in male patients, especially from T12 to L2 (P < 0.01). There were significant correlations between spinal canal and dural sac cross-sectional area (r = 0.55, P < 0.001), and also between CVR and DSCR (r = 0.31, P < 0.001). Of the levels decompressed, 82% was performed from the level L2 to L5, in which there was no significant difference in canal cross-sectional area and CVR between decompression and nondecompression (P > 0.05). There was a good correspondence between decreasing mean DSCR and increasing percentile of levels decompressed.

CONCLUSION

DSCR represents a useful method for the quantitative diagnosis of lumbar spinal canal stenosis. ImageTool software is a useful tool in measuring spinal morphometry.

Functional outcome of surgical treatment for multilevel lumbar spinal stenosis

BACKGROUND

There is no consensus regarding the best treatment of patients with multilevel lumbar stenosis. We evaluated the clinical and radiological findings in 41 patients with complex degenerative spinal stenosis of the lumbar spine who were treated surgically.

METHODS

Between 1997 and 2003, 41 patients suffering from degenerative lumbar spinal stenosis were included in a prospective clinical study. The spinal stenosis was multilevel in all patients and in 13 of them there was degenerative scoliosis, in 18 there was degenerative spondylolisthesis, and in 10 there was segmental instability. Plain radiographs, MRI and/or CT myelograms were obtained preoperatively. The patients were assessed clinically with the Oswestry disability index (ODI) and visual analog scale (VAS). Surgery included wide posterior decompression and fusion using a trans-pedicular instrumentation system and bone graft.

RESULTS

After a mean follow-up of 3.7 (1-6) years, the patients' clinical improvement on the ODI and VAS was statistically significant. Recurrent stenosis was not observed, and 39 of 41 patients were satisfied with the outcome. 3 patients with improvement initially had later surgery because of instability.

INTERPRETATION

The above-mentioned technique gives good and long lasting clinical results, when selection of patients is done carefully and when the spinal levels that are to be decompressed are selected accurately.

Costs and effects in lumbar spinal fusion. A follow-up study in 136 consecutive patients with chronic low back pain

Although cost-effectiveness is becoming the foremost evaluative criterion within health service management of spine surgery, scientific knowledge about cost-patterns and cost-effectiveness is limited. The aims of this study were (1) to establish an activity-based method for costing at the patient-level, (2) to investigate the correlation between costs and effects, (3) to investigate the influence of selected patient characteristics on cost-effectiveness and, (4) to investigate the incremental cost-effectiveness ratio of (a) posterior instrumentation and (b) intervertebral anterior support in lumbar spinal fusion. We hypothesized a positive correlation between costs and effects, that determinants of effects would also determine cost-effectiveness, and that posterolateral instrumentation and anterior intervertebral support are cost-effective adjuncts in posterolateral lumbar fusion. A cohort of 136 consecutive patients with chronic low back pain, who were surgically treated from January 2001 through January 2003, was followed until 2 years postoperatively. Operations took place at University Hospital of Aarhus and all patients had either (1) non-instrumented posterolateral lumbar spinal fusion, (2) instrumented posterolateral lumbar spinal fusion, or (3) instrumented posterolateral lumbar spinal fusion + anterior intervertebral support. Analysis of costs was performed at the patient-level, from an administrator's perspective, by means of Activity-Based-Costing. Clinical effects were measured by means of the Dallas Pain Questionnaire and the Low Back Pain Rating Scale at baseline and 2 years postoperatively. Regression models were used to reveal determinants for costs and effects. Costs and effects were analyzed as a net-benefit measure to reveal determinants for cost-effectiveness, and finally, adjusted analysis (for non-random allocation of patients) was performed in order to reveal the incremental cost-effectiveness ratios of (a) posterior instrumentation and (b) anterior support. The costs of non-instrumented posterolateral spinal fusion were estimated at DKK 88,285(95% CI 81,369;95,546), instrumented posterolateral spinal fusion at DKK 94,396(95% CI 89,865;99,574) and instrumented posterolateral lumbar spinal fusion + anterior intervertebral support at DKK 120,759(95% CI 111,981;133,738). The net-benefit of the regimens was significantly affected by smoking and functional disability in psychosocial life areas. Multi-level fusion and surgical technique significantly affected the net-benefit as well. Surprisingly, no correlation was found between treatment costs and treatment effects. Incremental analysis suggested that the probability of posterior instrumentation being cost-effective was limited, whereas the probability of anterior intervertebral support being cost-effective escalates as willingness-to-pay per effect unit increases. This study reveals useful and hitherto unknown information both about cost-patterns at the patient-level and determinants of cost-effectiveness. The overall conclusion of the present investigation is a recommendation to focus further on determinants of cost-effectiveness. For example, patient characteristics that are modifiable at a relatively low expense may have greater influence on cost-effectiveness than the surgical technique itself--at least from an administrator's perspective.