Chemonucleolysis versus discectomy: a randomized multicenter trial

Comparison of chemonucleolysis and discectomy in the management of lumbar disc herniation: a comprehensive systematic review and meta-analysis

Lumbar disc herniation (LDH) represents a significant cause of pain and physical impairment, negatively impacting the quality of life, and burdening healthcare systems. Despite numerous treatment strategies, optimal management remains a subject of debate. This meta-analysis aims to compare the efficacy and economic impact of chemonucleolysis (CN) and discectomy in the management of LDH. An extensive search of Embase, PubMed, and Cochrane databases yielded 391 records. Following strict inclusion and exclusion criteria, twenty-one studies suitable for a comparative analysis between CN and discectomy were included. This selection was based on patient improvement, including pain scores, complications, and differences in cost and surgery time. A total of 2436 patients were included in this study. Among them, 1,121 patients (46%) underwent discectomy, while 1,315 patients (54%) received the CN approach. Our analysis revealed that discectomy had a significantly higher improvement rate compared with chymopapain CN (OR: 0.45; 95%CI 0.23,0.88) and non-chymopapain CN (OR: 0.61; 95%CI 0.38,0.97). A non-significant inclination towards complication rates was observed with chymopapain CN (OR: 1.90; 95%CI 0.68,5.29). Notably, CN was associated with a considerable cost reduction (SMD: 7.11; 95%CI -11.37,-2.85) and a shorter surgical time (MD: -53.54; 95%CI -57.91,-49.17) compared with discectomy. The evidence synthesized in this meta-analysis suggests superior clinical outcomes for discectomy when compared to CN in managing LDH. However, CN demonstrated a notable advantage in terms of cost-efficiency and operative time, marking it as a potentially preferable option in resource-constrained settings. Nonetheless, more randomized clinical trials and prospective studies are necessary to confirm these findings.

Cell-based strategies for IVD repair: clinical progress and translational obstacles

Intervertebral disc (IVD) degeneration is a major cause of low back pain, a prevalent and chronic condition that has a striking effect on quality of life. Currently, no approved pharmacological interventions or therapies are available that prevent the progressive destruction of the IVD; however, regenerative strategies are emerging that aim to modify the disease. Progress has been made in defining promising new treatments for disc disease, but considerable challenges remain along the entire translational spectrum, from understanding disease mechanism to useful interpretation of clinical trials, which make it difficult to achieve a unified understanding. These challenges include: an incomplete appreciation of the mechanisms of disc degeneration; a lack of standardized approaches in preclinical testing; in the context of cell therapy, a distinct lack of cohesion regarding the cell types being tested, the tissue source, expansion conditions and dose; the absence of guidelines regarding disease classification and patient stratification for clinical trial inclusion; and an incomplete understanding of the mechanisms underpinning therapeutic responses to cell delivery. This Review discusses current approaches to disc regeneration, with a particular focus on cell-based therapeutic strategies, including ongoing challenges, and attempts to provide a framework to interpret current data and guide future investigational studies.

Canine models of spine disorders

Neck and low back pain are common among the adult human population and impose large social and economic burdens on health care and quality of life. Spine-related disorders are also significant health concerns for canine companions with etiopathogeneses, clinical presentations, and diagnostic and therapeutic options that are very similar to their human counterparts. Historically, induced and spontaneous pathology in laboratory rodents, dogs, sheep, goats, pigs, and nonhuman primates have been used for study of human spine disorders. While each of these can serve as useful preclinical models, they all have inherent limitations. Spontaneously occurring spine disorders in dogs provide highly translatable data that overcome many of the limitations of other models and have the added benefit of contributing to veterinary healthcare as well. For this scoping review, peer-reviewed manuscripts were selected from PubMed and Google Scholar searches using keywords: "intervertebral disc," "intervertebral disc degeneration," "biomarkers," "histopathology," "canine," and "mechanism." Additional keywords such as "injury," "induced model," and "nucleus degeneration" were used to further narrow inclusion. The objectives of this review were to (a) outline similarities in key features of spine disorders between dogs and humans; (b) describe relevant canine models; and (c) highlight the applicability of these models for advancing translational research and clinical application for mechanisms of disease, diagnosis, prognosis, prevention, and treatment, with a focus on intervertebral disc degeneration. Best current evidence suggests that dogs share important anatomical, physiological, histological, and molecular components of spinal disorders in humans, such that induced and spontaneous canine models can be very effective for translational research. Taken together, the peer-reviewed literature supports numerous advantages for use of canine models for study of disorders of the spine when the potential limitations and challenges are addressed.

Comparative clinical effectiveness of management strategies for sciatica: systematic review and network meta-analyses

BACKGROUND

There are numerous treatment approaches for sciatica. Previous systematic reviews have not compared all these strategies together.

PURPOSE

To compare the clinical effectiveness of different treatment strategies for sciatica simultaneously.

STUDY DESIGN

Systematic review and network meta-analysis.

METHODS

We searched 28 electronic databases and online trial registries, along with bibliographies of previous reviews for comparative studies evaluating any intervention to treat sciatica in adults, with outcome data on global effect or pain intensity. Network meta-analysis methods were used to simultaneously compare all treatment strategies and allow indirect comparisons of treatments between studies. The study was funded by the UK National Institute for Health Research Health Technology Assessment program; there are no potential conflict of interests.

RESULTS

We identified 122 relevant studies; 90 were randomized controlled trials (RCTs) or quasi-RCTs. Interventions were grouped into 21 treatment strategies. Internal and external validity of included studies was very low. For overall recovery as the outcome, compared with inactive control or conventional care, there was a statistically significant improvement following disc surgery, epidural injections, nonopioid analgesia, manipulation, and acupuncture. Traction, percutaneous discectomy, and exercise therapy were significantly inferior to epidural injections or surgery. For pain as the outcome, epidural injections and biological agents were significantly better than inactive control, but similar findings for disc surgery were not statistically significant. Biological agents were significantly better for pain reduction than bed rest, nonopioids, and opioids. Opioids, education/advice alone, bed rest, and percutaneous discectomy were inferior to most other treatment strategies; although these findings represented large effects, they were statistically equivocal.

CONCLUSIONS

For the first time, many different treatment strategies for sciatica have been compared in the same systematic review and meta-analysis. This approach has provided new data to assist shared decision-making. The findings support the effectiveness of nonopioid medication, epidural injections, and disc surgery. They also suggest that spinal manipulation, acupuncture, and experimental treatments, such as anti-inflammatory biological agents, may be considered. The findings do not provide support for the effectiveness of opioid analgesia, bed rest, exercise therapy, education/advice (when used alone), percutaneous discectomy, or traction. The issue of how best to estimate the effectiveness of treatment approaches according to their order within a sequential treatment pathway remains an important challenge.

Posterior endoscopic discectomy: Results in 300 patients

BACKGROUND

Posterior endoscopic discectomy is an established method for treatment of lumbar disc herniation. Many studies have not been reported in literature for lumbar discectomy by Destandau Endospine System. We report a series of 300 patients operated for lumbar dissectomy by Destandau Endospine system.

MATERIALS AND METHODS

A total of 300 patients suffering from lumbar disc herniations were operated between January 2002 and December 2008. All patients were operated as day care procedure. Technique comprised localization of symptomatic level followed by insertion of an endospine system devise through a 15 mm skin and fascial incision. Endoscopic discectomy is then carried out by conventional micro disc surgery instruments by minimal invasive route. The results were evaluated by Macnab's criteria after a minimum followup of 12 months and maximum up to 24 months.

RESULTS

Based on modified Macnab's criteria, 90% patients had excellent to good, 8% had fair, and 2% had poor results. The complications observed were discitis and dural tear in five patients each and nerve root injury in two patients. 90% patients were able to return to light and sedentary work with an average delay of 3 weeks and normal physical activities after 2 months.

CONCLUSION

Edoscopic discectomy provides a safe and minimal access corridor for lumbar discectomy. The technique also allows early postoperative mobilization and faster return to work.

Injection therapy and denervation procedures for chronic low-back pain: a systematic review

Injection therapy and denervation procedures are commonly used in the management of chronic low-back pain (LBP) despite uncertainty regarding their effectiveness and safety. To provide an evaluation of the current evidence associated with the use of these procedures, a systematic review was performed. Existing systematic reviews were screened, and the Cochrane Back Review Group trial register was searched for randomized controlled trials (RCTs) fulfilling the inclusion criteria. Studies were included if they recruited adults with chronic LBP, evaluated the use of injection therapy or denervation procedures and measured at least one clinically relevant outcome (such as pain or functional status). Two review authors independently assessed studies for eligibility and risk of bias (RoB). A meta-analysis was performed with clinically homogeneous studies, and the GRADE approach was used to determine the quality of evidence. In total, 27 RCTs were included, 14 on injection therapy and 13 on denervation procedures. 18 (66%) of the studies were determined to have a low RoB. Because of clinical heterogeneity, only two comparisons could be pooled. Overall, there is only low to very low quality evidence to support the use of injection therapy and denervation procedures over placebo or other treatments for patients with chronic LBP. However, it cannot be ruled out that in carefully selected patients, some injection therapy or denervation procedures may be of benefit.

A review of current treatment for lumbar disc herniation in children and adolescents

Lumbar disc herniation (LDH) is a common disorder among adults with degenerated lumbar intervertebral discs. However, its occurrence in childhood and adolescence is much less frequent mostly because children and adolescents tend to have a healthier lumbar spine as compared with adults. This difference indicates that children and adolescents are far from being just little adults. Over the years, there have constantly been published studies concerning this entity where the findings suggested that pediatric LDH is, in many ways, different from that in adults. To date, the prevalence, the etiological and the diagnostic features of pediatric LDH have been fully described in the literature whereas the characteristics regarding to the treatment is yet to be reviewed in details. The aim of the present review is to provide a collective opinion on the treatment of pediatric LDH as well as its outcome. It reviewed the relevant information available in the literature and compared the results among and within various treatments. It was found that pediatric patients responded less favorably to conservative treatment as compared with adults. In addition, the outcome of surgery remained to be satisfactory for at least 10 years after the initial operation, even though it appeared to deteriorate slightly. To the best of our knowledge, this is the first literature review focusing on the treatment of pediatric LDH.

Nonsurgical interventional therapies for low back pain: a review of the evidence for an American Pain Society clinical practice guideline

STUDY DESIGN

Systematic review.

OBJECTIVE

To systematically assess benefits and harms of nonsurgical interventional therapies for low back and radicular pain.

SUMMARY OF BACKGROUND DATA

Although use of certain interventional therapies is common or increasing, there is also uncertainty or controversy about their efficacy.

METHODS

Electronic database searches on Ovid MEDLINE and the Cochrane databases were conducted through July 2008 to identify randomized controlled trials and systematic reviews of local injections, botulinum toxin injection, prolotherapy, epidural steroid injection, facet joint injection, therapeutic medial branch block, sacroiliac joint injection, intradiscal steroid injection, chemonucleolysis, radiofrequency denervation, intradiscal electrothermal therapy, percutaneous intradiscal radiofrequency thermocoagulation, Coblation nucleoplasty, and spinal cord stimulation. All relevant studies were methodologically assessed by 2 independent reviewers using criteria developed by the Cochrane Back Review Group (for trials) and by Oxman (for systematic reviews). A qualitative synthesis of results was performed using methods adapted from the US Preventive Services Task Force.

RESULTS

For sciatica or prolapsed lumbar disc with radiculopathy, we found good evidence that chemonucleolysis is moderately superior to placebo injection but inferior to surgery, and fair evidence that epidural steroid injection is moderately effective for short-term (but not long-term) symptom relief. We found fair evidence that spinal cord stimulation is moderately effective for failed back surgery syndrome with persistent radiculopathy, though device-related complications are common. We found good or fair evidence that prolotherapy, facet joint injection, intradiscal steroid injection, and percutaneous intradiscal radiofrequency thermocoagulation are not effective. Insufficient evidence exists to reliably evaluate other interventional therapies.

CONCLUSION

Few nonsurgical interventional therapies for low back pain have been shown to be effective in randomized, placebo-controlled trials.

Surgery for low back pain: a review of the evidence for an American Pain Society Clinical Practice Guideline

STUDY DESIGN

Systematic review.

OBJECTIVE

To systematically assess benefits and harms of surgery for nonradicular back pain with common degenerative changes, radiculopathy with herniated lumbar disc, and symptomatic spinal stenosis.

SUMMARY OF BACKGROUND DATA

Although back surgery rates continue to increase, there is uncertainty or controversy about utility of back surgery for various conditions.

METHODS

Electronic database searches on Ovid MEDLINE and the Cochrane databases were conducted through July 2008 to identify randomized controlled trials and systematic reviews of the above therapies. All relevant studies were methodologically assessed by 2 independent reviewers using criteria developed by the Cochrane Back Review Group (for trials) and Oxman (for systematic reviews). A qualitative synthesis of results was performed using methods adapted from the US Preventive Services Task Force.

RESULTS

For nonradicular low back pain with common degenerative changes, we found fair evidence that fusion is no better than intensive rehabilitation with a cognitive-behavioral emphasis for improvement in pain or function, but slightly to moderately superior to standard (nonintensive) nonsurgical therapy. Less than half of patients experience optimal outcomes (defined as no more than sporadic pain, slight restriction of function, and occasional analgesics) following fusion. Clinical benefits of instrumented versus noninstrumented fusion are unclear. For radiculopathy with herniated lumbar disc, we found good evidence that standard open discectomy and microdiscectomy are moderately superior to nonsurgical therapy for improvement in pain and function through 2 to 3 months. For symptomatic spinal stenosis with or without degenerative spondylolisthesis, we found good evidence that decompressive surgery is moderately superior to nonsurgical therapy through 1 to 2 years. For both conditions, patients on average experience improvement either with or without surgery, and benefits associated with surgery decrease with long-term follow-up in some trials. Although there is fair evidence that artificial disc replacement is similarly effective compared to fusion for single level degenerative disc disease and that an interspinous spacer device is superior to nonsurgical therapy for 1- or 2-level spinal stenosis with symptoms relieved with forward flexion, insufficient evidence exists to judge long-term benefits or harms.

CONCLUSION

Surgery for radiculopathy with herniated lumbar disc and symptomatic spinal stenosis is associated with short-term benefits compared to nonsurgical therapy, though benefits diminish with long-term follow-up in some trials. For nonradicular back pain with common degenerative changes, fusion is no more effective than intensive rehabilitation, but associated with small to moderate benefits compared to standard nonsurgical therapy.

Surgical interventions for lumbar disc prolapse: updated Cochrane Review

STUDY DESIGN

An updated Cochrane Review.

OBJECTIVES

To assess the effects of surgical interventions for the treatment of lumbar disc prolapse.

SUMMARY OF BACKGROUND DATA

Disc prolapse accounts for 5% of low back disorders yet is one of the most common reasons for surgery. There is still little scientific evidence supporting some interventions.

METHODS

Use of standard Cochrane review methods to analyze all randomized controlled trials published up to January 1, 2007.

RESULTS

Forty randomized controlled trials (RCTs) and 2 quasi-RCTs were identified. Many of the early trials were of some form of chemonucleolysis, whereas the majority of the later studies either compared different techniques of discectomy or the use of some form of membrane to reduce epidural scarring. Four trials directly compared discectomy with conservative management, and these give suggestive rather than conclusive results. However, other trials show that discectomy produces better clinical outcomes than chemonucleolysis, and that in turn is better than placebo. Microdiscectomy gives broadly comparable results to standard discectomy. Recent trials of an interposition gel covering the dura (5 trials) and of fat (4 trials) show that they can reduce scar formation, although there is limited evidence about the effect on clinical outcomes. There is insufficient evidence on other percutaneous discectomy techniques to draw firm conclusions. Three small RCTs of laser discectomy do not provide conclusive evidence on its efficacy. There are no published RCTs of coblation therapy or transforaminal endoscopic discectomy.

CONCLUSION

Surgical discectomy for carefully selected patients with sciatica due to lumbar disc prolapse provides faster relief from the acute attack than conservative management, although any positive or negative effects on the lifetime natural history of the underlying disc disease are still unclear. The evidence for other minimally invasive techniques remains unclear except for chemonucleolysis using chymopapain, which is no longer widely available.

Minimally invasive spine surgery: a historical perspective

Minimally invasive spine surgery has gained considerable momentum and increased acceptance among spine surgeons throughout the years. An understanding and awareness of the development of minimally invasive spine surgery and its role in the operative treatment of various spine conditions is imperative. This article provides a succinct historical perspective of the development of spine surgery from the more traditional, open procedures to the use of more "minimal access" or minimally invasive spine surgery procedures.

Surgical interventions for lumbar disc prolapse

BACKGROUND

Disc prolapse accounts for five percent of low-back disorders but is one of the most common reasons for surgery.

OBJECTIVES

The objective of this review was to assess the effects of surgical interventions for the treatment of lumbar disc prolapse.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, PubMed, Spine and abstracts of the main spine society meetings within the last five years. We also checked the reference lists of each retrieved articles and corresponded with experts. All data found up to 1 January 2007 are included.

SELECTION CRITERIA

Randomized trials (RCT) and quasi-randomized trials (QRCT) of the surgical management of lumbar disc prolapse.

DATA COLLECTION AND ANALYSIS

Two review authors assessed trial quality and extracted data from published papers. Additional information was sought from the authors if necessary.

MAIN RESULTS

Forty RCTs and two QRCTs were identified, including 17 new trials since the first edition of this review in 1999. Many of the early trials were of some form of chemonucleolysis, whereas the majority of the later studies either compared different techniques of discectomy or the use of some form of membrane to reduce epidural scarring. Despite the critical importance of knowing whether surgery is beneficial for disc prolapse, only four trials have directly compared discectomy with conservative management and these give suggestive rather than conclusive results. However, other trials show that discectomy produces better clinical outcomes than chemonucleolysis and that in turn is better than placebo. Microdiscectomy gives broadly comparable results to standard discectomy. Recent trials of an inter-position gel covering the dura (five trials) and of fat (four trials) show that they can reduce scar formation, though there is limited evidence about the effect on clinical outcomes. There is insufficient evidence on other percutaneous discectomy techniques to draw firm conclusions. Three small RCTs of laser discectomy do not provide conclusive evidence on its efficacy, There are no published RCTs of coblation therapy or trans-foraminal endoscopic discectomy.

AUTHORS' CONCLUSIONS

Surgical discectomy for carefully selected patients with sciatica due to lumbar disc prolapse provides faster relief from the acute attack than conservative management, although any positive or negative effects on the lifetime natural history of the underlying disc disease are still unclear. Microdiscectomy gives broadly comparable results to open discectomy. The evidence on other minimally invasive techniques remains unclear (with the exception of chemonucleolysis using chymopapain, which is no longer widely available).

Chemonucleolysis in lumbar disc herniation: a meta-analysis

PURPOSE

To carry out a systematic review and meta-analysis of the efficacy of chemonucleolysis in the treatment of lumbar disc herniation.

METHODS

Clinical trials were selected from 3 electronic databases (The Cochrane Controlled Trials Register, MEDLINE, and EMBASE). Data were analyzed with the software STATA, using the meta command.

RESULTS

Twenty-two clinical trials were eligible. For chemonucleolysis versus placebo, the summary risk ratio estimate for pain relief as outcome was 1.51 (95% CI: 1.27-1.80). The summary estimate was 1.07 (95% CI: 0.95-1.20) for the comparison between chymopapain and collagenase. Regarding chemonucleolysis with chymopapain versus surgery, the fixed-effect summary estimate of effect for pain relief was 0.93 (95% CI: 0.88-0.98) with surgery as the reference group. In this case, heterogeneity was statistically significant.

CONCLUSIONS

Chemonucleolysis with chymopapain was superior to placebo and was as effective as collagenase in the treatment of lumbar disc prolapse. Results for studies comparing chemonucleolysis with surgery were heterogeneous, making it difficult to interpret the summary measure of effect.

Surgical interventions for lumbar disc prolapse

BACKGROUND

Disc prolapse accounts for five percent of low-back disorders but is one of the most common reasons for surgery.

OBJECTIVES

The objective of this review was to assess the effects of surgical interventions for the treatment of lumbar disc prolapse.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, PubMed, Spine and abstracts of the main spine society meetings within the last five years. We also checked the reference lists of each retrieved articles and corresponded with experts. All data found up to 1 June 2006 are included.

SELECTION CRITERIA

Randomized trials (RCT) and quasi-randomized trials (QRCT) of the surgical management of lumbar disc prolapse.

DATA COLLECTION AND ANALYSIS

Two review authors assessed trial quality and extracted data from published papers. Additional information was sought from the authors if necessary.

MAIN RESULTS

Thirty-nine RCTs and two QRCTs were identified, including 16 new trials since the first edition of this review in 1999. Many of the early trials were of some form of chemonucleolysis, whereas the majority of the later studies either compared different techniques of discectomy or the use of some form of membrane to reduce epidural scarring. Despite the critical importance of knowing whether surgery is beneficial for disc prolapse, only three trials have directly compared discectomy with conservative management and these give suggestive rather than conclusive results. However, other trials show that discectomy produces better clinical outcomes than chemonucleolysis and that in turn is better than placebo. Microdiscectomy gives broadly comparable results to standard discectomy. Recent trials of an inter-position gel covering the dura (five trials) and of fat (four trials) show that they can reduce scar formation, though there is limited evidence about the effect on clinical outcomes. There is insufficient evidence on other percutaneous discectomy techniques to draw firm conclusions. Three small RCTs of laser discectomy do not provide conclusive evidence on its efficacy, There are no published RCTs of coblation therapy or trans-foraminal endoscopic discectomy.

AUTHORS' CONCLUSIONS

Surgical discectomy for carefully selected patients with sciatica due to lumbar disc prolapse provides faster relief from the acute attack than conservative management, although any positive or negative effects on the lifetime natural history of the underlying disc disease are still unclear. Microdiscectomy gives broadly comparable results to open discectomy. The evidence on other minimally invasive techniques remains unclear (with the exception of chemonucleolysis using chymopapain, which is no longer widely available).

[Nucleolysis in the herniated disk]

Back pain associated with a herniated disk has become an important and increasing general health problem in Germany and other industrialized countries. After all methods of conservative treatment have been exhausted, nucleolysis may be a minimally invasive alternative to surgery. In nucleolysis, chondrolytic substances or other substances, which reduce the pressure within the disk by other means, are injected into the nucleus pulposus under CT guidance. Among various substances, which have been employed for nucleolysis, an ozone-oxygen mixture appears to be very promising. The water-binding capacity of ozone results in a reduction of pain for several months. Moreover, it has an anti-inflammatory effect and results in an increase of perfusion. Ozone is converted into pure oxygen in the body and has a low allergic potential. Recent minimally invasive therapeutic methods such as percutaneous nucleotomy or laser treatment do not result in superior results compared with nucleolysis.

Outcome of invasive treatment modalities on back pain and sciatica: an evidence-based review

Within the framework of evidence-based medicine high-quality randomised trials and systematic reviews are considered a necessary prerequisite for progress in orthopaedics. This paper summarises the currently available evidence on surgical and other invasive procedures for low back pain. Results of systematic reviews conducted within the framework of the Cochrane Back Review Group were used. Data were gathered from the latest Cochrane Database of Systematic Reviews 2005, Issue 2. The Cochrane reviews were updated using the evidence summary on surgery and other invasive procedures from the COST B13 European Guidelines for the Management of Acute and Chronic Non-Specific Low Back Pain. Facet joint, epidural, trigger point and sclerosant injections have not clearly been shown to be effective and can consequently not be recommended. There is no scientific evidence on the effectiveness of spinal stenosis surgery. Surgical discectomy may be considered for selected patients with sciatica due to lumbar disc prolapses that fail to resolve with the conservative management. Cognitive intervention Combined with exercises is recommended for chronic low back pain, and fusion surgery may be considered only in carefully selected patients after active rehabilitation programmes during 2 years time have failed. Demanding surgical fusion techniques are not better than the traditional posterolateral fusion without internal fixation.

Surgical treatments for lumbar disc disease in adolescent patients; chemonucleolysis / microsurgical discectomy/ PLIF with cages

The herniated lumbar disc (HLD) in adolescent patients is characterized by typical discogenic pain that originates from a soft herniated disc. It is frequently related to back trauma, and sometimes it is also combined with a degenerative process and a bony spur such as posterior Schmorl's node. Chemonucleolysis is an excellent minimally invasive treatment having these criteria: leg pain rather than back pain, severe limitation on the straight leg raising test (SLRT), and soft disc protrusion on computed tomography (CT). Microsurgical discectomy is useful in the cases of extruded or sequestered HLD and lateral recess stenosis due to bony spur because the nerve root is not decompressed with chymopapain. Spinal fusion, like as PLIF, should be considered in the cases of severe disc degeneration, instability, and stenosis due to posterior central bony spur. In our study, 185 adolescent patients, whose follow-up period was more than 1 year (the range was 1-4 years), underwent spinal surgery due to HLD from March, 1998 to December, 2002 at our institute. Among these cases, we performed chemonucleolysis in 65 cases, microsurgical discectomy in 94 cases, and posterior lumbar interbody fusion (PLIF) with cages in 33 cases including 7 reoperation cases. The clinical success rate was 91% for chemonucleolysis, 95% for microsurgical disectomy, and 89% for PLIF with cages, and there were no non- union cases for the PLIF patients with cages. In adolescent HLD, chemonucleolysis was the 1st choice of treatment because the soft adolescent HLD was effectively treated with chemonucleolysis, especially when the patient satisfied the chemonucleolysis indications.

Assessing observational studies of spinal fusion and chemonucleolysis

STUDY DESIGN

Literature review and survey of spine surgeons.

OBJECTIVES

To identify reasons for variation in results among observational studies of spinal surgery.

SUMMARY AND BACKGROUND DATA

Orthopedic treatments are often evaluated by observational studies rather than randomized controlled trials. The value of observational studies is debated.

METHODS

A literature search was performed to find several observational studies that compared the same spinal surgeries. Possible confounders for these studies were identified by a survey of spinal surgeons. Study characteristics from these articles were tested for an association with study results.

RESULTS

Most observational studies were case series. Articles studied in depth included 20 evaluating chemonucleolysis and 14 evaluating spinal arthrodesis for patients who had herniated disc or spinal stenosis. For each treatment comparison, results varied from strongly favoring one treatment to strongly favoring the other. Apparent causes of the variation were patient selection criteria, the choice of outcome measure, and follow-up rate. Few studies reported on the potential confounders identified by physician surveys, and only one study used statistical methods to reduce the influence of confounding.

CONCLUSIONS

The results suggest that review of several comparable observational studies may help evaluate treatment, identify patient types most likely to benefit from a give treatment, and provide information about study features that can improve the design of subsequent observational or randomized controlled studies. The potential of comparative observational studies has not been realized because of current inadequacies in their design, analysis, and reporting.

Current Concepts in Minimally Invasive Discectomy

OBJECTIVE

The purpose of this study was to evaluate the various minimally invasive procedures available for the treatment of lumbar disc disease.

METHODS

A review of the literature, as well as my personal experience with minimally invasive approaches to the lumbar discs, was performed. This review included the percutaneous and open surgical approaches currently available and used for the treatment of lumbar disc disease.

RESULTS

The primary minimally invasive procedures for the treatment of lumbar disc disease include the following: 1) chemonucleolysis, introduced by Lyman Smith in 1964; 2) percutaneous manual nucleotomy, introduced by Hijikata in 1975; 3) microdiscectomy, first performed by Yaşargil in 1968; 4) automated percutaneous lumbar discectomy, introduced by Onik in 1984; 5) laser discectomy, first performed by Ascher and Choy in 1987; 6) endoscopic discectomy, first used by Schreiber and Suezawa in 1986 and improved by Mayer, Brock, and Mathews; 7) microendoscopic discectomy, introduced by Smith and Foley in 1995; and 8) intradiscal electrothermy, first reported by Saal and Saal in 2000.

CONCLUSION

Although all percutaneous techniques have been reported to yield high success rates, to date no studies have demonstrated any of these to be superior to microsurgical discectomy, which continues to be regarded as the standard with which all other techniques must be compared.

Review of safety in endoscopic laser foraminoplasty for the management of back pain

OBJECTIVE

The purpose of this study was to analyze the incidence and gravity of reported complications that arise in spinal surgery and assess the comparative safety, or otherwise, of endoscopic laser foraminoplasty (ELF).

BACKGROUND DATA

Chemonucleolysis, decompression, discectomy, and fusion have long been cited as treatments for chronic low back pain. Over recent years newer, less invasive surgical techniques have become available, one such being ELF. Although minimally invasive, the beneficial outcome must be interpreted in relation to concerns regarding the safety of the procedure and its risks relative to those of other forms of spinal surgery. The Spinal Foundation, Rochdale has performed 958 ELFs and has collated a comprehensive database of the results of all these operations. These prospective records provided the basis for a comparison of the safety of ELF to that reported with other spinal surgical techniques.

METHODS

A total of 958 procedures have been performed on 716 patients. Complications that arose during the operation and the postoperative phase of 6 weeks following the procedure were elicited from patient records. These data were correlated and compared to a meta-analysis of randomized controlled clinical trial data of complications arising during and after conventional spinal surgery. The SPSS (statistical package for social sciences) and CIA (confidence interval analysis) statistical packages were used to draw conclusions regarding the safety of ELF.

RESULTS

The cohort integrity of operation and outpatient review records at 6 weeks after surgery was 100%. In 958 ELFs performed, 24 complications occurred in 23 patients. There were 9 cases of discitis (1 infective, 8 aseptic) (0.9%), 1 dural tear (0.1%), 1 deep wound infection (0.1%), 2 patients suffered a foot drop (1 transient) (0.2%), 1 myocardial infarction (0.1%), 1 erectile dysfunction (0.1%), and 1 patient who developed panic attacks post-operatively (0.1%). This amounts to an overall surgical complication rate of 1.6%. Magnetic resonance imaging (MRI) follow up of clinically symptomatic patients highlighted 8 residual disc herniations (0.8%). Meta-analysis of randomized controlled trials of conventional spinal surgery for adult onset degenerative disc disease and/or sciatic pain reported overall complication rates for fusion (11.8%), decompression (7.6%), discectomy (6.0%), and chemonucleolysis (9.6%).

CONCLUSIONS

The complication rate of ELF is shown to be significantly lower than that reported following conventional spinal surgery (p < 0.01). From these results, we conclude that ELF as a treatment for chronic low back pain and sciatica presents less risk to a patient than conventional methods of spinal surgery.

Patient-oriented outcomes from low back surgery: a community-based study

STUDY DESIGN

This study used a prospective cohort design.

OBJECTIVE

To examine factors associated with favorable self-reported patient outcomes 1 year after elective surgery for degenerative back problems.

SUMMARY OF BACKGROUND DATA

Many previous studies addressing the results of low back surgery have been conducted in academic institutions or by single surgeons. As part of a quality improvement effort, surgeons in private practice led a community-based outcomes management project in Washington State.

METHODS

Patients ages 18 and older with the following diagnoses were eligible for the study: degenerative changes, herniated disc, instability, and spinal stenosis. Nine orthopedists and neurosurgeons enrolled a total of 281 patients. Participants were asked to complete baseline and 1-year follow-up surveys. Data concerning diagnoses, clinical signs, and operative procedures were provided by the surgeons. The researchers examined sociodemographic characteristics, self-reported symptoms before surgery, preoperative clinical signs, diagnoses, and operative procedures associated with three primary outcomes: better functioning, improved quality of life, and overall treatment satisfaction.

RESULTS

Follow-up surveys were completed by 236 (84%) of the enrolled patients. Approximately two thirds of the study participants reported much better functioning (65%), a great quality of life improvement (64%), and a very positive perspective about their treatment outcome (68%). The following variables were associated with worse patient outcomes: older age, previous low back surgery, workers' compensation coverage, and consultation with an attorney before surgery. Patients undergoing a fusion procedure were more likely to report good outcomes.

CONCLUSIONS

The authors' experience indicates that community-based outcomes data collection efforts are feasible and can be incorporated into usual clinical practice. The study results indicate that compensation payments and litigation are two important predictors of poor outcomes after low back surgery in community practice. Because of small numbers, varied diagnoses, and possible selection bias, the findings with respect to fusion should be interpreted cautiously.

The Cochrane review of surgery for lumbar disc prolapse and degenerative lumbar spondylosis

STUDY DESIGN

A Cochrane review of randomized controlled trials.

OBJECTIVES

To collate the scientific evidence on surgical management for lumbar-disc prolapse and degenerative lumbar spondylosis.

SUMMARY OF BACKGROUND DATA

Surgical investigations and interventions account for as much as one third of the health care costs for spinal disorders, but the scientific evidence for most procedures still is unclear.

METHODS

A highly sensitive search strategy identified all published randomized controlled trials. Cochrane methodology was used for meta-analysis of the results.

RESULTS

Twenty-six randomized controlled trials of surgery for lumbar disc prolapse and 14 trials of surgery for degenerative lumbar spondylosis were identified. Methodologic weaknesses were found in many of the trials. Only one trial directly compared discectomy and conservative management. Meta-analyses showed that surgical discectomy produces better clinical outcomes than chemonucleolysis, which is better than placebo. Three trials showed no difference in clinical outcomes between microdiscectomy and standard discectomy, but in three other studies, both produced better results than percutaneous discectomy. Three trials showed that inserting an interposition membrane after discectomy does not significantly reduce scar formation or alter clinical outcomes. Five heterogeneous trials on spinal stenosis and degenerative spondylolisthesis permit very limited conclusions. There were nine trials of instrumented versus noninstrumented fusion: Meta-analysis showed that instrumentation may facilitate fusion but does not improve clinical outcomes.

CONCLUSIONS

There is now strong evidence on the relative effectiveness of surgical discectomy versus chemonucleolysis versus placebo. There is considerable evidence on the clinical effectiveness of discectomy for carefully selected patients with sciatica caused by lumbar disc prolapse that fails to resolve with conservative management. There is no scientific evidence on the effectiveness of any form of surgical decompression or fusion for degenerative lumbar spondylosis compared with natural history, placebo, or conservative management. The Cochrane reviews will be updated continuously as other trials become available.

Efficacy of lumbar discectomy and percutaneous treatments for lumbar disc herniation

The changing health care environment necessitates careful re-evaluation of all costly elective procedures. Low back surgery is a typical example. This article reviews the current literature addressing the efficacy of surgery and invasive percutaneous treatments for discogenic sciatica. It also discusses the prospects for the continuation of reimbursement for these procedures under a system of managed health care. Relevant articles were identified using the MEDLINE and Current Contents databases, from bibliographies of articles identified from these databases, from recommendations of experts in the field, and from the Canadian Cochrane++ Collaboration. The review includes randomized clinical trials, meta-analyses, published practice guidelines and large case series. The literature is classified and discussed in these quality strata. The review includes 9 randomized trials, 6 meta-analyses or review articles, one evidence-based practice guideline, 38 surgical case series and 35 additional references. Though incomplete, the existing evidence indicates that open discectomy shortens the duration of discogenic sciatica in selected patients. Neurologic outcomes are similar in operated and unoperated patients. Predominant leg pain, evidence of nerve root tension and concordant symptoms and imaging findings, are associated with favorable surgical results. Chemonucleolysis is also associated with more rapid pain relief than conservative treatment, but provides less certain benefit than standard discectomy. Available data on other percutaneous disc treatments do not currently support a statement on efficacy. Various percutaneous techniques are available but there is no solid scientific evidence of efficacy. The benefits of open discectomy, principally reduced duration of pain, appear to justify its use in carefully selected patients when discogenic sciatica fails to improve with conservative measures. Though elective, the procedure will probably continue to be available under managed care, but with increasing scrutiny of operative indications.

Randomized controlled trials in industrial low back pain relating to return to work. Part 2. Discogenic low back pain

The purpose of this review was to determine the efficacy of treatments for discogenic low back pain (LBP) by examining all randomized controlled trials (RCTs) of discogenic LBP published in the English language literature between 1975 and 1993 with "return to work" (RTW) as the end point. From more than 4,000 LBP citations, nearly 600 articles were initially reviewed; 35 studies met our selection criteria. Twenty-two studies were discussed in Part 1 (Acute Interventions) or will be discussed in Part 3 (Chronic Interventions). In this review, of 13 RCTs assessing interventions for LBP with sciatica, 9 were appropriate for their focus on, and radiologic confirmation of, discogenic LBP. The treatments assessed included chemonucleolysis, surgical discectomy, and epidural steroid injection. A 26-point system to assess the quality of methodologic rigor was used for each article. Our literature survey found a need for additional studies comparing surgery, conservative care, epidural steroids, traction, and other approaches to determine their individual effects for RTW after discogenic disease.

The Maine Lumbar Spine Study, Part II. 1-year outcomes of surgical and nonsurgical management of sciatica

STUDY DESIGN

The Maine Lumbar Spine Study is a prospective cohort study of patients recruited from the practices of orthopedic surgeons, neurosurgeons, and occupational medicine physicians throughout Maine.

OBJECTIVE

To assess 1-year outcomes of patients with sciatica believed to be due to a herniated lumbar disc treated surgically or nonsurgically.

SUMMARY OF BACKGROUND DATA

Lumbar spine surgery rates vary by geographic region and may reflect uncertainty about optimal clinical use.

METHODS

Eligible consenting patients participated in a baseline interview performed by study personnel and then were mailed follow-up questionnaires at 3, 6, and 12 months. Clinical data were obtained from a physician questionnaire. Outcomes included patient-reported symptoms of leg and back pain, functional status, disability, quality of life, and satisfaction with care.

RESULTS

Five hundred seven patients with sciatica, 275 treated surgically and 232 treated nonsurgically initially, were enrolled. Surgically treated patients, on average, had more severe symptoms and had more severe physical and imaging findings than nonsurgically treated patients at entry. Although few surgically treated patients had mild symptoms and few nonsurgically treated patients had severe symptoms, about half in each treatment group had symptoms that fell into a moderate category. At the 1-year evaluation, improvement in symptoms, functional status, and disability were found in both treatment groups. However, surgically treated patients reported significantly greater improvement. For the predominant symptom, either back or leg pain, 71% of surgically treated and 43% of nonsurgically treated patients reported definite improvement (P < 0.001). This effect was even greater after adjustment for differences between treatment groups at entry (relative odds of definite improvement, 4.3; P < 0.001). For patients with moderate symptoms and abnormal physical examination findings, surgical treatment also resulted in greater improvement than nonsurgical treatment. However, there was little difference in the employment or workers' compensation status of patients treated surgically versus nonsurgically (5% vs. 7% unemployed at 1-year follow-up if employed at entry [P = 0.68]; 46% vs. 55% receiving workers' compensation at 1-year follow-up if receiving it at entry [P = 0.30] for surgical and nonsurgical management, respectively). For patients with mild symptoms, the benefits of surgical and nonsurgical treatment were similar.

CONCLUSIONS

Although surgically treated patients were on average more symptomatic at entry, there was substantial overlap in symptoms between surgically treated and nonsurgically treated patients. Surgically treated patients with sciatica reported substantially greater improvement at 1-year follow-up. However, employment and compensation outcomes were similar between the two treatment groups, and surgery appeared to provide little advantage for the subset of patients with mild symptoms. These results should be interpreted cautiously, because surgical treatment was not assigned randomly. Long-term follow-up will determine if these differences persist.

Postchemonucleolysis discectomy versus repeat discectomy: a prospective 1- to 13-year comparison

This long-term prospective study evaluates the clinical results of subsequent laminectomy in 103 consecutive patients who initially underwent chemonucleolysis (CNL) or laminectomy for lumbar disc herniation. Between 1981 and 1994, 53 patients who had received CNL initially and then underwent laminectomy and 50 patients treated initially with laminectomy underwent a repeat laminectomy. Clinical assessment at 6 weeks showed a success rate of 80.8% for post-CNL laminectomy and 78% for repeat laminectomy. At 6 months, the success rate for patients treated with CNL was 86% versus 78.7% for laminectomy. At 12 months, the overall success rate for the CNL group was 80.4% versus 83.3% for the laminectomy group, but in patients who had not obtained relief from the first procedure the success rate for the second procedure was higher for the post-CNL patients. A questionnaire was sent to all patients for 1- to 13-year follow-up review. The average follow-up period was 6.6 years for post-CNL laminectomy and 5.2 years for repeat laminectomy. The long-term success rate (81.8%) was higher in the post-CNL group compared to 64.4% in the repeat laminectomy group. Seven patients in the post-CNL group and nine in the repeat laminectomy group had undergone a third operation. When these originally successfully treated patients were reassigned after unsuccessful outcomes, the success rate for the CNL groups was 72.7%, versus 51.1% in the laminectomy group (p = 0.049). Employment rates were 80% for patients with CNL (21.8% changed jobs) and 76.3% for patients undergoing laminectomy (48.3% changed jobs) (p = 0.036). In conclusion, patients who underwent laminectomies after receiving CNL had significantly better long-term results than those who had repeat laminectomies.

Cost-effectiveness of lumbar discectomy for the treatment of herniated intervertebral disc

STUDY DESIGN

A cost-effectiveness analysis of lumbar discectomy based on existing efficacy data and newly gathered cost data.

OBJECTIVES

For patients with herniated lumbar discs unresponsive to conservative management, surgery relieves pain more rapidly but at higher costs than continued medical therapy. We evaluated the cost-effectiveness of lumbar discectomy for these patients.

SUMMARY OF BACKGROUND DATA

Effectiveness estimates were based on the results of a published trial of 126 herniated disc patients randomized to surgical or nonsurgical treatment. Quality of life values were based on a study of 83 subjects with low back pain. Treatment costs for herniated discs were estimated from insurance data for 372 patients treated surgically and 1,803 treated medically.

METHODS

Efficacy results were weighted by quality of life values to estimate the quality-adjusted benefit of surgery. Cost-effectiveness was calculated in dollars per quality-adjusted year of life gained. Supplemental data sources for cost and effectiveness provided ranges for sensitivity analyses.

RESULTS

Surgery increased average quality-adjusted life expectancy by 0.43 years during the decade following treatment, a benefit similar to extending a healthy life by 5 months. Reimbursements for surgical patients were $12,550 more than for medical patients. Nondiscounted and 5% discounted cost-effectiveness were $29,200 and $33,900 per quality-adjusted year of life gained. Supplemental analyses confirmed the basecase effectiveness estimates but suggested that the cost of discectomy was overestimated. Replacing the main cost estimate with one based on HMO patients lowered discectomy's cost to $12,000 per quality-adjusted life-year gained.

CONCLUSION

For carefully selected patients with herniated discs, surgical discectomy is a cost-effective treatment. Discectomy's favorable cost-effectiveness results from its substantial effect on quality of life and moderate costs.

[Current therapeutic options in sciatica caused by disk herniation]

The results of reliable therapeutic trials, experimental studies showing that compression is not the only mechanism of nerve root alterations, and mainly, the favorable spontaneous outcome of 95% of the sciatica command a critical approach of all the treatments of sciatica by disc herniation. A disc herniation can be observed in 20% of asymptomatic population. Except neurological complications requiring an early surgical decompression, the management of sciatica should begin by a 2 to 3 months period of medical treatment including analgesic drugs or NSAID, a 8 to 10 day bed rest, epidural corticosteroid injections validated in controlled studies, and a lumbar brace during 4 to 6 weeks. The reference treatment of disc herniation in patients whose conservative treatment failed is conventional surgery. The average rate of failure following decompressive surgery is 15 to 20% and the need for further surgery ranges from 5 to 15%. The main cause of failure is the absence of true compressive herniation before the initial operation. Microscope removal of disc herniation does not lead to better results than the standard procedure and there is a 20% risk of recurrence when only the herniated fragment is removed. The success rate of chemonucleolysis approaches 65-70% but the procedure need a strict care to prevent severe complications. Manual percutaneous discectomy, whatever the procedure are supported only by uncontrolled studies. The only randomized trial in automated percutaneous discectomy versus chemonucleolysis reported a 37% success rate with a one-year follow-up. Benefit/risk ratio should always be considered before every treatment of sciatica.

Surgery for herniated lumbar discs: a literature synthesis

OBJECTIVE

To assess the risks and benefits of surgery for herniated lumbar discs (discectomy) and to evaluate the methodologic quality of the literature.

DESIGN

Literature synthesis. STUDY SELECTION AND DATA ANALYSIS: A structured MEDLINE search identified studies of standard, microsurgical, or percutaneous discectomy. Eligible studies had adult subjects, sample sizes of > or = 30, clinical outcome data for > or = 75% of patients, and follow-up of > or = 1 year. Summary rates of successful outcomes, reoperations, and complications were obtained by a random-effects logistic regression model. Methodologic quality was assessed using established study design criteria.

RESULTS

Eighty-one studies met inclusion criteria. Most had substantial design flaws and/or omitted important clinical data. Randomized trials of standard discectomy showed better short-term sciatica relief following surgery; 65% to 85% of patients reported no sciatica one year after surgery, compared with only 36% of conservatively treated patients. No data from randomized trials were available for microdiscectomy or percutaneous discectomy, although most outcomes appeared comparable to those of standard discectomy. Approximately 10% of discectomy patients underwent further back surgery, and rates increased over time. The rate of serious complications, including death and permanent neurologic damage, was less than 1%.

CONCLUSIONS

Most studies were poorly designed and reported. Standard discectomy appears to offer better short-term outcomes than does conservative treatment, but long-term outcomes are similar. Discectomies are relatively safe procedures, though reoperations are common and increase over time. Decisions for elective surgery must balance faster pain relief against the risks and costs of surgery.

A 1- to 4-year follow-up review of treatment of sciatica using chemonucleolysis or laminectomy

To help clarify the comparative effects of chemonucleolysis and discectomy, the author studied 178 consecutive patients with sciatica who did not respond to conservative treatment. None had previously undergone laminectomy or chemonucleolysis or had spinal stenosis. All received postmyelography computerized tomography (CT) and, if the radiological interpretation was that of an extruded migrated disc, a laminectomy was performed; otherwise, the patient was given a choice of the two procedures. Of the 178 patients, 106 underwent chemonucleolysis and 72 laminectomy. Workers' compensation was being paid to 21.6% of the chemonucleolysis patients and 20.8% of the laminectomy patients. Postoperatively, substantial improvement was noted in 82.7% of the chemonucleolysis patients and 92.5% of the laminectomy patients at 6 weeks and in 92.8% of the chemonucleolysis patients and 89.7% of the laminectomy patients at 6 months. The majority of patients in both groups had improved neurological signs. Follow-up questionnaires at 1 to 4 years postoperatively revealed an overall success rate of 86.5% for chemonucleolysis patients and 83.8% for laminectomy patients. In patients not receiving workers' compensation, 90.1% of the chemonucleolysis patients and 88.6% of the laminectomy patients had a successful outcome; in those receiving workers' compensation, 69.6% of the chemonucleolysis patients and 60.0% of the laminectomy patients had a successful outcome. No statistically significant differences in improvement rate in neurological symptoms or signs were identified between the two procedures. Overall, 85.1% of the chemonucleolysis patients and 78.5% of the laminectomy patients were employed at follow-up review. To achieve optimum results and eliminate noncandidates for chemonucleolysis, routine use of postmyelography CT is recommended. When properly used, chymopapain chemonucleolysis is an acceptable alternative to surgical discectomy.