Infection after intradiscal injections has been recognised as a distinct entity, but discitis after discography has often been attributed to an aseptic process or a chemical reaction to the contrast material. We examined the hypothesis that discitis after discography is always due to infection, and report a clinical review and an experimental study. Part I. We reviewed the case records and radiographs of 432 patients who had undergone lumbar discography. When an 18-gauge needle without a stilette had been used, discitis was diagnosed in 2.7% of 222 patients but stiletted needles and a two-needle technique at each level reduced the incidence to 0.7%. Seven patients with discitis after discography had undergone anterior discectomy and fusion; in them the histopathological findings were of a chronic inflammatory response. Bacteria were isolated from the discs of three of the four patients who had open biopsy less than six weeks from the time of discography. These findings suggest that bacteria were initiators rather than promoters of the response. Part II. Multiple level lumbar discography was carried out in mature sheep, injecting contrast material with or without various concentrations of bacteria. Radiographs were taken and the discs and end-plates were examined histologically and cultured for bacteria at intervals after injection. None of the controls showed any evidence of discitis but all sheep injected with bacteria had typical radiological and histopathological changes by six weeks, though cultures were almost all negative. However, at one and two weeks after injection, but usually not after three weeks, bacteria could be isolated. We suggest that all cases of discitis after discography are initiated by infection, and that a very strict aseptic technique should be used for all injections into intervertebral discs

Introduction Historically, lumbar discography has been one of the most controversial subjects in the management of discogenic low back pain. The diagnostic value of normal psychometric specific pain provocation by disc pressurization has emerged. The sensitivity, specificity and accuracy of discography as a diagnostic test are not in doubt. In clinical discography pain reproduction and location are essential elements. There is an accepted rate of 0–10% false positives. This rate is influenced by occupational disability and abnormal psychometric profiles. By contrast, little attention has been given to false negative results and their outcomes if surgically treated. Traditionally, whether or not the test is considered to be positive or negative is determined immediately after completion of the diagnostic procedure. This study shows that patient’s pain reproduction may occur up to 24 hours after the discogram which often initially interpreted as a true negative when it is actually a false negative result. This study verifies the existence and significance of a false negative through the patients’ treatment and outcomes. Methods In this study, 150 patients underwent discography for investigation of chronic persistent low back pain (CPLBP). All patients had a control (morphologically normal) discogram at the level above the degenerative segment. No patients with abnormal psychometric profiles or compensation were included. All patients were followed up 24 hours post discogram by the radiologist to further assess their clinical status. Ten of the patients (7.5%) were considered to have a false negative discogram, as per the Dallas Discogram Scale. The surgeon correlated the delayed response on the subsequent follow-up. These ten patients were diagnosed as having a positive response and were treated surgically for their discogenic pain. VAS-B, VAS-L, ODI, RMD were collected prospectively. Preoperative and 6 month results were reviewed. Results Seven of the 10 patients (70%) reported severe increase CPLBP and reproduction of pain within 8 hours of the discogram, while 3 patients (30%) did so in the ensuing 24 hours after the discogram. Surgical treatment was either by total disc replacement or anterior lumbar interbody fusion. All patients reported greater than 50% reduction in VAS-B and VAS-L and with improvements of greater than 50% in their ODI and RMD scores. Discussion The clinical reliability of discography hinges on the subjective assessment of pain concordance as the discriminating factor in determining false positives from false negatives. Given the limitations of discography, all information about the patient should be considered prior to diagnosis, including clinical, radiological, historical, and psychometric factors. The delayed positive discography response is an important consideration for the patient, the radiologist, and the treating surgeon to be aware of. The results of this study verify the existence of this subgroup and justify their surgical treatment

Aims. The presence of facet tropism has been correlated with an elevated susceptibility to lumbar disc pathology. Our objective was to evaluate the impact of facet tropism on chronic lumbosacral discogenic pain through the analysis of clinical data and finite element modelling (FEM). Methods. Retrospective analysis was conducted on clinical data, with a specific focus on the spinal units displaying facet tropism, utilizing FEM analysis for motion simulation. We studied 318 intervertebral levels in 156 patients who had undergone provocation discography. Significant predictors of clinical findings were identified by univariate and multivariate analyses. Loading conditions were applied in FEM simulations to mimic biomechanical effects on intervertebral discs, focusing on maximal displacement and intradiscal pressures, gauged through alterations in disc morphology and physical stress. Results. A total of 144 discs were categorized as ‘positive’ and 174 discs as ‘negative’ by the results of provocation discography. The presence of defined facet tropism (OR 3.451, 95% CI 1.944 to 6.126) and higher Adams classification (OR 2.172, 95% CI 1.523 to 3.097) were important predictive parameters for discography-‘positive’ discs. FEM simulations showcased uneven stress distribution and significant disc displacement in tropism-affected discs, where loading exacerbated stress on facets with greater angles. During varied positions, notably increased stress and displacement were observed in discs with tropism compared to those with normal facet structure. Conclusion. Our findings indicate that facet tropism can contribute to disc herniation and changes in intradiscal pressure, potentially exacerbating disc degeneration due to altered force distribution and increased mechanical stress. Cite this article: Bone Joint Res 2024;13(9):452–461

In a prospective study we attempted to define the role of lumbar discography in the investigation of patients with low back pain with or without non-dermatomal pain in the lower limb. The records of 195 patients were studied at least two years after a technically successful operation. Of 137 patients in whom discography had revealed disc disease and provoked symptoms, 89% derived significant and sustained clinical benefit from operation. Of 25 patients whose discs showed morphological abnormality but had no provocation of symptoms on discography only 52% had clinical success. These findings support the continued use of lumbar discography for the investigation of this particular group of patients

Discitis after discography is due to bacterial penetration into the intervertebral disc by a contaminated needle and has an incidence of 1% to 4%. We have examined the prophylactic role of cephazolin administered at the time of discography. An experimental study in sheep using radiographic contrast containing Staphylococcus epidermidis showed that either adding the antibiotic to the intradiscal suspension or giving it intravenously 30 minutes before intradiscal inoculation of bacteria prevented any radiographic, macroscopic or histological signs of discitis; all the intervertebral disc cultures were negative. In a prospective clinical study of 127 consecutive patients having lumbar discography, the injected contrast contained cephazolin 1 mg per ml. None of the patients developed clinical or radiographic signs of discitis. We recommend the use of a suitable broad spectrum antibiotic in a single prophylactic dose whenever the intervertebral disc is entered

We attempted to correlate the findings of MRI and discography in patients with low back pain, examining 108 lumbar intervertebral discs in 33 consecutive patients. MRI results were assessed from the intensity and shape of the signal obtained from the central part of the disc. Discography was classified according to the pattern of contrast material, the pressure accepted and the pain reproduced. All discs which were abnormal on MRI had altered patterns on discography, but 18 of the 60 discs with normal MRI had abnormal discograms. Of 39 asymptomatic discs, 33 had normal MRI signals and 24 had normal discograms. None of the 15 discs showing severe degeneration on MRI sustained high levels of intradiscal pressure, but only six of the 60 discs giving normal MRI had low pressure. With current techniques, discography is more accurate than MRI for the detection of annular pathology: a normal MRI does not exclude significant changes in the peripheral structure of the intervertebral disc which can produce low back pain

Prospective match cohort study of disc degeneration progression over ten years with and without baseline discography. To compare progression of common degenerative findings between lumbar discs injected ten years earlier with those same disc levels in matched subjects not exposed to discography. Seventy-five subjects without serious low back pain illness underwent a protocol MRI and a L3/4, L4/5 and L5 S1 discography in 1997. A match group was enrolled at the same time and underwent the same protocol MRI examination. Subjects were followed for ten years. At 7 to 10 years after baseline assessment, eligible discography in controlled subjects underwent another protocol MRI. MRI graders, blind to group designation, scored both groups for qualitative findings. Well matched cohorts, including 50 discography subjects and 52 control subjects met eligibility criteria for follow up evaluation. In all graded or measured parameters, discs that had been exposed to puncture and injection had greater progression of degenerative findings compared to control (non-injected) discs: progression of disc degeneration, 54 discs (35%) in the discography group compared to 21 (14%) in the control group (p=0.03); 55 new disc herniations in the discography group compared to 22 in the control group (p=0.0003). New disc herniations were disproportionately found on the side of the annular puncture (p=0.0006). The quantitative measures of disc height and disc signal also showed significantly greater loss of disc height (p=0.05) and signal intensity (p=0.001) in the discography disc compared to the control disc. This study demonstrates that the dimensions of the LSP change with age. Increases in LSP height occur with age. More impressive increases in LSP width occur with advancing age. This study suggests that loss of lumbar lordosis is correlated with changing LSP morphology. The increased width of the LSP with age influences access to the spinal canal, particularly if midline-preserving approaches are attempted in the ageing population. There is increased bone volume for bone grafting procedures with increasing age. The reduced distance between LSPs with age may influence design of implants that stabilize this region of the spine, and occur not only as a result of disk space narrowing, but also as a consequence of increased LSP dimensions

Introduction: The role of discography before lumbar fusion had been discussed in the literature. No study discussed its role before total lumbar disc replacement (TDR). Degenerate discs are not necessarily painful, even if they show Modic changes or HIZ. Moreover, discogenic pain might not be the predominant element in the patient’s symptoms and most of the back pain could be originating form other spinal structures. The aim of our prospective cohort study is to show whether or not provocative discography plays any significant role before TDR and to define that role. Methods: Twenty patients (11 females and 9 males) had “Prodisc” TDR. Mean age = 38.5 years (range: 20–56). All patients had mechanical low back pain with degenerative disc disease diagnosed by MRI scan. 65% (N=13) had radicular pain as well. The mean duration of back pain = 66.9 months (range: 16–240). Pre-operative provocative discography was performed in all cases. The clinical outcome was assessed by comparing the preoperative SF36-v2, ODI and VAS scores’ means to the 3, 6, 12 and 24 months post-operative ones and also comparing the last follow up SF36-v2 scores with the, age and sex adjusted, normative data for the general UK population obtained from the Oxford Healthy Lifestyle Survey III. All patients were followed up for a minimum of 2 years. Results: 90% (N=18) experienced a clinically significant improvement of their back pain (MCID for SF36-v2 scales=1SD, ODI=10 points and VAS=2 points). There has been a statistically significant improvement in the follow up outcome measures (P< 0.05) at 3, 6, 12 and 24 mths. SF 36-v2 scores of 15% of patients (N=3) reached or exceeded the normative values for the UK general population. Conclusion: Provocative discography is an important diagnostic tool before TDR. It is the only dynamic method to diagnose discogenic pain and is indispensable to exclude the painless levels in cases of multilevel disc degeneration

This prospective study was carried out to correlate findings of magnetic resonance imaging (MRI) and discography. Fifty-five consecutive patients with degenerative disc disease not responding to non-operative treatment were included in the study. There were 19 men and 36 women and the mean age was 45 years. Discography was carried out on 131 disc levels. The discograms were classified using modified Adams’s classification and pain recorded into three grades. MRI scans were graded using a new classification system based on parasagittal and axial images by two independent observers blinded to discography findings. There was good intraobserver (kappa 0. 74) and interobserver (kappa 0. 70) agreement for the classification system. There was a significant correlation in the morphology of discs as determined by discograms and MRI classification (p< 0. 001). Each disc was graded on MRI scan as painful or painless on basis of defined criteria. Concordant discography pain was considered as the gold standard. The sensitivity and specificity of MRI in predicting symptomatic disc using defined criteria was 94% and 77%. The sensitivities and specificity of high intensity zones was 27% and 87% and for end plate changes was 32% and 98% respectively. In 14 patients (25%) the findings of MRI and discography did not correlate. In conclusion though MRI is an excellent investigation for assessing disc morphology it should be interpreted along with discography findings before planning fusion surgery. The proposed MRI classification is a useful aid in predicting painful degenerative disc. The utility of high intensity zones and end plate changes is limited due to low sensitivity

Two different classifications of discograms have been used in a prospective study of 279 injected discs in 100 patients. The five-stage classification of Adams, Dolan and Hutton (1986) showed increased degeneration in the lower lumbar discs and more degenerative changes in men than in women. Exact reproduction of the patient's pain on injection was more common in fissured or ruptured discs than in less degenerate discs, with 81% sensitivity and 64% specificity of the discogram for pain. The additional information obtained by comparing computerised tomography (CT) with discograms was minimal. Discography was found to be useful in the evaluation of chronic low back pain in patients whose ordinary CT scans, myelograms and flexion-extension radiographs were normal. In spondylolysis and spondylolisthesis, discography can disclose whether fusion needs to be extended above the lytic level, and it may show if the pain in patients who have had posterolateral fusion is discogenic. Thus, discography gives information which is useful in deciding whether to operate on patients with chronic low back pain

We analysed the functional outcome (Oswestry Disability Index) after technically and radiologically successful lumbar fusion in 39 non-compensation seeking patients with chronic low back pain, who had a High Intensity Zone (HIZ) – positive MRI and subsequently underwent discography. The average follow-up was 33 months. The HIZ-positive, discogrampositive group was the only one with statistically significant improvement. The HIZ-positive, discogram-negative group had the worst outcome. Relying only on the HIZ fails to identify the group of patients who would have had negative discography at the same levels. Therefore the presence of HIZ alone should not dictate treatment plan without discography confirmation

Background: Over several decades, investigators have been trying to identify the painful degenerate disc. Their work included two main methods. The first was to set criteria on the radiological investigations, mainly the MRI scan, to describe the severity of the degenerative disc disease (DDD); and the second was to perform discographies. Neither of these two methods precluded the need for the other. Purpose: Using Pfirrmann’s classification, we correlated static MRI images, for the severity of segmental disc degeneration, with dynamic lumbar discography, with the aim to improve the identification of painful ‘disco-genic’ intervertebral segments. Study design: Prospective cohort study. Inclusion criteria included patients with mechanical low back pain who exhausted the conservative measures and required surgical treatment. Patient Sample and Methods: We investigated 69 patients (45 females, 24 males). The average age was 38.9 years (range 20–56). All patients had degenerative disc disease (DDD) on lumbar MRI scans. Provocative discographies were performed in all cases as a routine investigation to identify painful levels prior to fusion or disc replacement surgery. The severity of DDD was graded using Pfirrmann’s classification. A total of 162 discographies were performed using the ‘miss the facet joint, double needle technique’. Outcome measures: During discography typical or concordant pain only was regarded as positive. Among each of the five Pfirrmann grades, the percentage of positive discographies was calculated. Significance and correlation then were investigated using the Chi-squared and Spearman’s correlation tests. Results: 24 discs were classified as Pfirrmann grade I, 33 grade II, 63 grade III, 27 grade IV and 15 grade V. The percentages of positive provocative discography for concordant pain among these groups were 0%, 9.1%, 71.4%, 100% and 100% respectively. Statistical analysis showed a high correlation between the severity of DDD on MRI scan and the result of the provocative discography (Chi2 = 32.96, P < 0.001 and correlation coefficient = 0.756). Conclusion: The higher the grade of segmental DDD, the more likely it will be painful on discography. All discs showing Pfirmann grade IV and V disease were painful on discography. We strongly recommend the Pfirrmann classification for use in grading the severity of lumbar DDD especially when assessing for its association with discogenic pain as determined by provocative discography

The lumbar spines of 22 patients were examined for disc degeneration by magnetic resonance imaging (MRI) and by discography. The results from 50 intervertebral discs visualised by both techniques were independently assessed and graded on a five-point scale from normality to gross degeneration and then compared. In 44 discs the results agreed. Of the six discs which gave differing results, four discrepancies were due to observer error and two to incorrect placement of the discographic needle. MRI was shown to be more accurate than discography in the diagnosis of disc degeneration. It has several major advantages, which should make it the investigation of choice

Introduction: Recent cadaveric studies have identified neovascularisation and neoneuralisation as probable mechanisms in the causation of discogenic pain. Calcium pyrophosphate deposits have been observed in discs in several studies. Their significance in the causation of discogenic pain is unclear. Direct correlation between the pain site and histological features can be verified by aware state endoscopic visualisation. Aim and Objectives: The study aims to examine and correlate the presence of neovascularisation, crystalline pyrophosphate deposits in the disc, and discogenic pain by spinal probing and discography under endoscopic visualisation. Material and Methods: Tissue removed from intervertebral discs of 224 patients during surgery was examined directly, and polarised microscopy was used to identify the presence of calcium pyrophosphate and neovascularisation. Their presence was correlated to diagnostic provocative findings of spinal probing and discography and intradiscal distortion during aware state endoscopy. Results: Calcium Pyrophosphate: Twenty out of 224 patients (9%) demonstrated calcium pyrophosphate in the discs. Fourteen had pain reproduced on probing or discography. Thirteen out of 20 patients (65%) had either an annular collection or leak at the index level. 6 had an extradiscal cause of pain. One hundred percent of the patients with annular collections or leaks had pain on spinal probing or discography. Sixteen patients with pyrophosphate deposits did not have neovascularisation. Neovascularisation: Thirty seven out of 224 patients (16.5%) showed neovascularisation in the disc. Four discs had crystalline pyrophosphate deposits. Thirty three out of 37 (90%) had pain on probing and/or discography. Out of four patients who had no pain on probing or discography, two had demonstrated tears during previous discographic procedures which were treated with laser annealing. These patients had disc bulges and compressive radiculopathy. Conclusion: The presence of pyrophosphate in the disc without a tear or leak does not directly render them tender to provocation. The presence of pyrophosphate is not correlated to neovascularisation. Annular tears or leaks are not directly correlated to the presence of pyrophosphates. There is a high correlation between pain provocation and neovascularisation

Discogenic low back pain is a common cause of disability, but its pathogenesis is poorly understood. We collected 19 specimens of lumbar intervertebral discs from 17 patients with discogenic low back pain during posterior lumbar interbody fusion, 12 from physiologically ageing discs and ten from normal control discs. We investigated the histological features and assessed the immunoreactive activity of neurofilament (NF200) and neuropeptides such as substance P (SP) and vasoactive-intestinal peptide (VIP) in the nerve fibres. The distinct histological characteristic of the painful disc was the formation of a zone of vascularised granulation tissue from the nucleus pulposus to the outer part of the annulus fibrosus along the edges of the fissures. SP-, NF- and VIP-immunoreactive nerve fibres in the painful discs were more extensive than in the control discs. Growth of nerves deep into the annulus fibrosus and nucleus pulposus was observed mainly along the zone of granulation tissue in the painful discs. This suggests that the zone of granulation tissue with extensive innervation along the tears in the posterior part of the painful disc may be responsible for causing the pain of discography and of discogenic low back pain

Introduction. Degenerative disc disease results from mechanical alteration of the intervertebral disc. Biochemical modifications of the nucleus matrix are also incriminated. Furthermore, genetic predispositions as well as vascular factors have been advocated in the process of disc degeneration. A relationship between sciatica and Propionibacterium acnes has been described. However, it remains unclear if the hypothesis of a subclinical spondylodiscitis might play a role in the pathophysiology of degenerative disc disease. The purpose of this study was to analyze the possible presence of bacteria in lumbar discs of patients with degenerative disc disease. Methods. We prospectively analyzed the presence of bacteria in 83 patients (34 males and 49 females, average age 41 years) treated by lumbar disc replacement at L3-L4, L4-L5 or L5-S1. An intraoperative biopsy and microbiological culture were performed for each disc to determine if intradiscal bacteria were present. Great care was taken to avoid any source of contamination during the conditioning process of the biopsy. Microbiological results were compared to the magnetic resonance stages of disc degeneration according to the Pfirrmann and Modic classifications. Possible sources of previous iatrogenic disc contamination after discography or nucleotomy were analyzed. Results. The magnetic resonance stages were Pfirrmann IV or V, with Modic I signs in 32 and Modic II in 25 cases. A preoperative discography was performed in 49 patients, and 24 had previous nucleotomy. Germs were found in 40 discs, 43 cultures were steriles. The following bacteria were evidenced: Propionibacterium acnes 18, Staphylococcus coagulase negative 16, Staphylococcus aureus 3, Gram negative bacilli 3, Micrococcus 3, Corynebacterium 3, others 5. Ten biopsies presented several different germs. Bacteria were predominantly found in males (p=0.012). The mostly positive level was L4-L5 (p=0.075). Histological examination of 31 discs found inflammatory cells in 33 % of the biopsies with positive bacterial culture, versus 5 % of the sterile biopsies (p=0.038). There was no significant relationship between bacterial evidence and Modic sign. A preoperative discography or previous nucleotomies did not represent significant contamination sources. None of the patients presented clinical signs of infection. Conclusions. The finding of bacteria in 48 % of disc biopsies, presence of inflammatory cells at histological examination, the absence of responsibility of the discography as a factor of contamination, and the absence of clinical post-operative infection, defend the hypothesis of a low-grade spondylodiscitis which might play a role in the pathophysiology of degenerative disc disease. On the other hand, the presence of skin commensal bacteria, of ¼ of polymicrobial biopsies, and the fact that previous nucleotomy doesn't seem to be involved in inoculation, cannot allow to eliminate a contamination of the samples. Further studies are necessary to elucidate the responsability of intradiscal bacteria in degenerative disc disease. This could influence our treatment strategy of back pain, which could be based in the future on antibiotics

Objectives: To examine and correlate the presence of neovascularisation, crystalline pyrophosphate deposits and other hisotological features in the disc and discogenic pain established by spinal probing and discography under aware state endoscopic visualisation. Design: Tissue removed from intervertebral discs of 224 patients during surgery were examined by direct and polarised microscopy to identify the presence of calcium pyrophosphate and neovascularisation. Material and Methods: Histology was correlated to the diagnostic provocative findings of spinal probing and discography, discal palpation during aware state endoscopy. Results:Calcium Pyrophosphate: 20/224 (9%) patients demonstrated calcium pyrophosphate in the discs. Fourteen had pain reproduced on probing or discography; 13/20 (65%) of patients had either an annular collection or leak at the index level; 6/20 had an extradiscal cause of pain. Neovascularisation: Thirty-seven out of 224 (16.5%) patients showed neovascularisation in the disc; four discs had crystalline pyrophosphate deposits; 33/37 (90%) had pain on probing and/or discography. Conclusion: The presence of pyrophosphate in a disc without a tear or leak is not associated with annular tenderness. The presence of pyrophosphates in radial tears or leaks is associated with annular tenderness. Annular tears or leaks are not directly correlated to the presence of pyrophosphates. There is a high correlation between pain provocation and neovascularisation

Problem Chronic disabling pain in the sacrococcygeal region is regarded by clinicians with great dismay because of unpredictability of the treatment outcome. The subject is under- represented in the literature. Method Thirty eight patients with intractable coccydynia had imaging investigations for the spine other than X-rays. Six of these patients were also investigated by means of sacrococcygeal and intercoccygeal discography. The excised specimen with intact sacrococcygeral joint was sent for histological examination in 22 patients. Patients’ assessment of the benefit of coccygectomy was conducted by telephonic interview. Results After a mean post surgical follow up of 6.75 years (range 2–16 yrs), results were available for 31 out of 38 patients. 16 patients benefited greatly from the surgery and 6 benefited to some extent, giving an overall good result of 71%. 7 patients had no or little relief from surgery (29%). Moderate to severe degenerate changes in SC and IC joints on histology were found in 59% of patients. 91.6 % of these patients did well with surgery. Only 60 % of those with mild changes did well. Discography was possible in five out of six attempted cases. Two were positive and both did well from surgery. Three patients had negative discographies and two of them had a poor result and one had only some relief. Conclusions Degenerate changes in sacrococcygeal discs give rise to pain. Surgical results are better in those with a severe degree of degenerative change. It is possible to identify these with discography, though a larger study needs to be carried out

Purpose. By systematic literature review, to quantify the association between vertebral endplate signal changes (VESC) and non-specific low back pain (NSLBP). Materials and methods. MEDLINE, EMBASE, and SveMED databases were searched for the period 1984 to June 2009. Articles were included which investigated the association between VESC and NSLBP and reported sufficient data to construct two-by-two tables. Articles on specific low back pain conditions were excluded. A standardised data collection and quality assessment were performed. To estimate the association between VESC and NSLBP, two-by-two tables were created and exact odds ratios were calculated with 95% confidence intervals (CI). Meta-analysis was performed on homogeneous studies. Results. Fourteen articles met the inclusion criteria. A statistically significant positive association between VESC and NSLBP was found in 10 of 14 studies from the general, working, and clinical populations with odds ratios ranging from 2.0 to 27.9. Two of the other four studies showed positive associations, one study a neutral association and the other a negative association but all these results were not statistically significant. Meta-analysis of the eight discography studies included in the review showed a pooled odds ratio between VESC and pain on discography of 4.50 (CI 1.96-10.32). The median prevalence of pain on discography was 88.8% in people with VESC and 41.6% in those without VESC (46.8% overall). Conclusions. The results from this systematic review show that VESC in the lumbar spine is associated with pain and therefore should be noted routinely in MRI reports

Aim: To assess the outcome of patients with chronic discogenic lumbar back pain who underwent intradiscal electro thermal therapy (IDET). Design: A prospective longitudinal study. Subjects: Patients undergoing IDET in our unit between April 2000 and October 2007 were included in the study after assessment with discography and diagnostic imaging. Discographic concordant symptoms with subsequent abolition with local anaesthetic led to inclusion in the study regardless of discogram volume. Outcome Measures: Subjects were assessed preoperatively with VAS pain scores, SF36, demographic data and pain diagrams. Then were then reassessed postoperatively with the, VAS pain scores SF36, employment status and subjective outcome at 6, and 12 months. Results: 83 patients were treated with IDET. We had a follow up rate of 75% leaving a cohort of 65 patients. Mean follow up 7.6 months. Overall there was a mean improvement in pain VAS scores of 1.9 (p=0.0875). SF36 scores showed minimal improvement in both physical and mental parameters and there was minimal improvement in subjective outcome in 55% of patients. However it was observed that a small subgroup of patients (30%) aged less than 40 with low volume positive discography and single level disease mean pain VAS scores improved by 3.78 from 7.52 to 3.74. 72% of these patients reported a subjective improvement in symptoms and SF36 scores improved significantly compared to the overall group. Further analysis also revealed that the use of pain diagrams when interpreted according to the principles of Mann et al was the predictive value. Conclusions: Patient selection seems to be crucial in determining a successful outcome using IDET. We still perform this procedure on those patients aged less than 40 with single level disease, positive low volume discography, no facet joint arthritis and an organic pre procedure pain diagram

There are many difficulties associated with the localisation of the symptomatic segment in patients presenting with cervicobrachial pain with no evidence of impaired conduction in the nerve root. Ancillary radiological investigations such as myelography, epidural phlebography, and epidural myelograms are of unreliable diagnostic value. However, discography can be of value if the technique described here is used. Infiltration of the cervical nerve root with local anaesthetic has also proved useful in the localisation of the symptomatic segment. The techniques used in cervical discography and infiltration of the nerve root are described and their reliability is assessed

We report a series of 98 patients with back pain and sciatica in whom the MRI scan was reported as normal. The patients were referred by their General Practitioners and the MRI was the first and only investigation. The patients were subsequently subjected to plain radiographs including weight-bearing spot laterals of the lumbo-sacral spine, and discography in which pain provocation and reversal were judged as indicative of a pain source. Significant degenerative change was noted in plain radiographs in 27 cases, and weight-bearing views revealed a spondylolisthesis in eight cases where the supine view and MR had appeared normal. Discography had revealed intradiscal fissuring correlating with pain reproduction and reversal in 36 cases. MRI is a scarce resource with very long waiting lists in many parts of the country and the value of the investigation may have been exaggerated both in terms of false positive and false negative results. On the basis of our study we recommend a review of radiological policy

Magnetic resonance imaging (MRI) of the spine produces images which reflect the chemical composition of the intervertebral disc. We have conducted a prospective study of the serial changes in the MRI appearance of the intervertebral disc after chemonucleolysis with the enzyme chymopapain. Fourteen patients were studied after single-level chemonucleolysis and the results compared with a control group of 17 discs in six patients who had diagnostic discography without enzyme insertion. A consistent pattern of gradual loss of signal from the nucleus pulposus culminating in complete loss of nuclear signal was seen in all cases after chemonucleolysis. Chymopapain therefore produced MRI changes analogous with premature gross disc degeneration. The rate at which this occurred varied; complete loss of signal took at least six weeks. Transitory minor end-plate changes were present in five patients, probably representing a mild chemical discitis. No similar changes were seen in the discography group

Objective: To report a randomised controlled trial (RCT) of the therapeutic efficacy of intradiscal steroid injection for the treatment of discogenic back pain after two years. Introduction: Discography remains the main method to assess whether a degenerate disc is the source of back pain. The treatment of such discogenic pain is difficult. There is only one previous RCT of the use intradiscal steroids, but with a short follow-up. Patients and Methods: 120 consecutive patients with positive discography were randomised intra-operatively to receive an intradiscal injection of saline or 40mgs Depomedrone. Outcome was assessed using a back pain questionnaire at six weeks, three and six months, and at two years. Pain (using a visual analogue score), disability (the Oswestry Disability Index), and psychological status (DRAM score) were measured. The results were correlated with Modic changes and high intensity zones on MRI scan. Results: An initial improvement of back pain in the steroid group is not maintained at two years, with no statistical difference between the two groups. Correlation of the results with the MRI findings will be presented. Conclusion: This study demonstrates the need for long-term follow-up of such intradiscal therapeutic methods of treating discogenic pain

Aims: MRI changes to the symptomatic intervertebral disc following Intradiscal Electrothermal Therapy (IDET), in particular those relating to the Ç High Intensity Zone È (HIZ) in the posterior annulus, were determined in this prospective study. Methods: MRI images before the IDET procedure were compared to those taken at six months post procedure in 10 patients. The presence and absence of an HIZ, the disc height and hydration, and Modic changes, were determined from the images. Two of the patients also had discography performed post-IDET to supplement the MRI. Results: In 6 out of the 10 patients, an HIZ was present on the MRI images of the disc before the IDET procedure. In all 6 patients, a HIZ was still present six months after the procedure. In all 10 patients, there were no changes to disc height and hydration signal on T2 weighted images. Modic changes were not present in any of the patients on pre or post IDET images. Two patients had signiþ-cant changes to the shape of the posterior annulus compared to the pre-treatment MRI scans. The two patients who had discography after IDET had persistent annular tears. Conclusion: Our þndings question the clinical relevance of the Ç High Intensity Zone È. They also suggest that the main mechanism of action of IDET, may be other than that of sealing the annular tear

Introduction: We report a series of 10 cases from a cohort of 421 Dynesys procedures in which evidence of Accelerated Adjacent Disc Disease (AASDD). Spinal fusion for degenerative disc disease is known to have inconsistent outcomes. One concern is the possibility of AASDD as a result of the altered kinematics. The Dynamic Neutralisation System (Dynesys) appears to offer an advantage in that it restricts, rather than abolishes movement at the treated segment, and should thereby reduce the problem of AASDD, In the event of failure, it can in addition be removed, returning the spine to the former status quo. Various biomechanical studies confirmed flexibility of Dynesys. Method: Ten patients developed new and symptomatic disc disease within segments adjacent to Dynesys. The average age of patients was 49 year with range between 36–70 years. Average post Dynesys to secondary surgery for ASD was 24.7 months. Previous discography and MRI in all cases had shown no evidence of disc disease within these adjacent segements prior to Dynesys. All patients were evaluated preoperatively using Oswestry Disability Index, SF 36 and Visual Analogue Scores together with plain x ray imaging, MRI scanning and discography. Of this cohort Dynesys was indicated to treat single disc level in 7 and two levels in 3. Results: Incidence of AASDD associated with Dynesys was 2.1%. Further surgical intervention included:. Extension of Dynesys10. Dynesys combined with MIF2. Dynesys combined with PLIF2. There was no caudal ASD in our cohort. Discussion & Conclusions: Dyensys did not prevent the development of accelerated ASD. Evidence from Aylott cadaver studies suggests that Dynesys instrumentation alters the Kinematics of the adjacent segment and increases the excursion. It is unclear whether the small number of AASDD reported here is other than the natural progression of degenerative change. 95.7 cases did not progress

Objective: MRI changes to the symptomatic intervertebral disc following Intradiscal Electrothermal Therapy (IDET), in particular those relating to the “High Intensity Zone” (HIZ) in the posterior annulus, were determined in this prospective study. Material and Methods: MRI images before the IDET procedure were compared to those taken at six months post procedure in 10 patients. The presence and absence of an HIZ, the disc height and hydration, and Modic changes, were determined from the images. Two of the patients also had discography performed post-IDET to supplement the MRI. Results: In 6 out of the 10 patients, an HIZ was present on the MRI images of the disc before the IDET procedure. In all 6 patients, a HIZ was still present six months after the procedure. In all 10 patients, there were no changes to disc height and hydration signal on T. 2. weighted images. Modic changes were not present in any of the patients on pre or post IDET images. Two patients had significant changes to the shape of the posterior annulus compared to the pre-treatment MRI scans. The two patients who had discography after IDET had persistent annular tears. Conclusion: Our findings question the clinical relevance of the “High Intensity Zone”. They also suggest that the main mechanism of action of IDET, may be other than that of sealing the annular tear

Introduction The aim of the study was to determine the prevalence of different causes of neck pain in a private practice clinic by a retrospective audit of records. Methods The study included all consecutive patients attending a private spine pain clinic in the state of Washington, USA, seen between January 2003 and January 2005, in whom a diagnosis of neck pain was made. The records of all patients were examined to determine the prevalence of various diagnostic entities determined by history, examination, and invasive tests such as controlled diagnostic blocks and provocation discography. Using different denominators, the prevalence of various conditions was determined in all patients who presented with neck pain, in patients in whom investigations were undertaken, and in patients who completed investigations. Results A large proportion of patients (35%) did not pursue investigations, which diluted the crude prevalence of various conditions. A further 17% deferred completing investigations. Amongst the 48% of patients who completed investigations, the prevalence of zygapophysial joint pain was 55%, discogenic pain was 16%, and lateral atlanto-axial joint pain was 9%. A diagnosis remained elusive in only 17% of those patients who completed investigations. Discussion In a private practice setting, a patho-anatomic diagnosis for chronic neck pain can be established in over 80% of patients, provided that appropriate investigations are undertaken. The prevalence of cervical zygapophysial joint pain encountered in the present study corroborates the prevalence rates established in academic studies. The observed prevalence of discogenic pain is probably an underestimate because not all eligible patients underwent discography

Thirteen patients with symptomatic disc herniation in the cervical spine were treated with percutaneous laser disc decompression (PLDD). Patients included 10 males and 3 females with a mean age of 41.4 (range, 24–60) years old. Preoperative symptom was divided into 2 types; myelopathy in 8 and radiculopathy in 5 patients. The level of the treated disc, which was diagnosed from the provoked cervicobrachial neuralgia during discography, distributed to C4/5 in 1, C5/6 in 8, C6/7 in 4 patients. The Nd:YAG laser (1064 nm) was percutaneously irradiated to the involved disc through a needle of 1.5 mm with a mean energy of 600 joules. Clinical evaluations were assessed with modified Macnab`s criteria at a mean follow-up period of 3 years (range, 0.5–5.7 years) excluding one patient who received open surgery 3 weeks after PLDD. Six patients (46.2%) showed good to excellent results without any significant complications. Four patients of 7 with unsuccessful results received a subsequent open surgery. There was no significant difference between successful and unsuccessful group in gender, disc level, preoperative duration of symptoms, positive provocation during discography, and the total amount of irradiated energy. Patients with successful results tended to be younger with a mean age of 35.7 years compared to those with unsuccessful results with a mean of 46.3 (p=0.053). Clinical outcome in two patients with radiculopathy were judged as excellent. Although postoperative MRI revealed few morphological changes on the disc in 2–3 weeks after PLDD, MRI at the final follow-up showed remarkable decrease of signal intensity in the disc. On postoperative radiographs, the disc height and the range of motion during flexion to extension in the treated discs significantly decreased, indicating the acceleration of disc degeneration and the resultant stabilization of the segment

Study Design: Prospective cohort study. Summary of Background data: A definite link between Modic end plate changes and discogenic low back pain has yet to be established. However, current prospective data indicates that Modic changes strongly correlate with the pain provocation of lumbar discography and improved clinical outcome following instrumented posterolateral fusion. Consequently, there is recent heightened awareness using this radiological entity in the selection of patients for interbody fusion or total disc replacement. Objective: To prospectively evaluate whether Modic changes can predict improved clinical outcome following antero-posterior lumbar interbody fusion using femoral ring allograft. Methods: A cohort of chronic low back pain patients were investigated with MRI and lumbar discography. Twenty-six patients with disco-graphically-proven concordant pain reproduction were prospectively entered into the study. Clinical results were collected using the Oswestry Disability Index (ODI), Visual Analogue Scale (VAS) and Short Form 36 Health Questionnaire (SF-36) at the pre-operative and two-year follow up. The minimal clinically important difference (MCID) was taken as 10 points for ODI, 2 points for VPAS, and 7 points for the physical function and bodily pain subset of the SF-36 questionnaire. Results: MRI scans evaluated for the level fused revealed 13 patients with no end-plate changes (Type 0), whilst 2 patients had Modic Type I and 11 had Modic Type II changes. MCID in ODI were achieved in Type 0, Type 1 and Type 2, but improvement in VAS only was achieved in the Type 0 and Type 1. For SF-36, the MCID of 7 points was reached in most domains for all types of Modic change. There was no statistical difference in clinical outcome between those patients with Modic Type 0 and those with Modic type I or II. Conclusion: This prospective study shows that Modic changes do not predict improved clinical outcome following antero-posterior interbody fusion using the femoral ring allograft

Purpose: In this prospective study we present the intermediate results of our experience using the Prodisc disc replacement for lumbar degenerative disc disease. Methods and Results: A total of 29 patients underwent Prodisc disc replacement by the senior author(AAH). There were 9 males and 20 females with a mean age of 39 years(Range 28–60 years). 18 patients had a single level disc replacement (L5/S1-- 14 patients, L4/5-- 4 patients). 11 patients had double level disc replacement (L4/5& L5/S1--7 patients, L3/4& L4/5--3 patients, L2/3& L3/4--1 patient). All patients were assessed pre-operatively with clinical examination, plain films, MRI scans and discography. The indication for surgery was discogenic pain at one or two adjacent segments confirmed with discography, minimum six months of conservative treatment, 20–60 years of age and an Oswestry score > 40%. All patients also agreed to a prearranged follow up protocol. Follow up included clinical examination, plain films and subjective evaluation using the Oswestry scale, Visual Analogue Scale and SF 36 scoring system at 6 weeks, 3 months, 6 months and annually. Results- The follow up range was from 3 months to 2 years. 26 patients had excellent to very good results and 2 patients had good results. There was one complication at 3 months post operatively. This patient sustained a fractured pedicle and underwent revision surgery involving removal of the prosthesis and Anterior Lumbar Fusion. At 6 months post revision a CT scan confirmed fusion. Rapid recovery was the most noticeable aspect of this study as well as rapid return to normal activities. Conclusion: The Prodisc disc replacement is a good treatment option for lumbar degenerative disc disease provided the operative indications are strictly adhered to. The early and mid term results presented are encouraging, however close follow up of these patients is essential to ascertain the long term results

Routine use of Computed Tomography (CT) to evaluate discogram morphology is time consuming, costly and incurs additional radiation hazards. In our spinal unit, discography is routinely performed without the aid of CT. Discogram morphology for different stages of disc degeneration is evaluated using the modified Adam’s grading system on images obtained on fluoroscopy. Our aims were to assess the validity of the modified Adam’s grading system of discogram morphology, by assessing its inter- and intra-observer agreement. We reviewed the discographic images (133 intervertebral levels) of 71 patients with chronic low back pain undergoing discography as part of a preoperative assessment between 1995 and 1997. Using the modified Adam’s grading system, three independent surgeon observers of three levels of experience (Senior Fellow, Senior and Junior residents) retrospectively evaluated the morphological appearance of each disc level in a randomized and blinded manner. Each observer was supplied with descriptions and illustrations of the 5 grades1, and each level was classified accordingly. The exercise was repeated three weeks later. The respective inter- and intra-observer agreements were calculated using the kappa statistic (Fleiss 1971) and generalized kappa statistic (Landis and Koch 1977). The inter-observer agreement was excellent (kappa = 0.77; standard error = 0.054). The intra-observer agreement for each of the three observers was also excellent (kappa = 0.8, 0.8, and 0.85 with respective standard errors = 0.046, 0.049 and 0.042). Significance and conclusions: The inter- and intra-observer agreement and therefore the reliability of the modified Adam’s grading system is excellent. This classification is easy to apply and has a high degree of reproducibility amongst observers with different levels of spinal experience. In view of the high reproducibility, we recommend the Adam’s classification for the grading of discogram morphology. The routine use of computed tomography with the concomitant radiation exposure and additional cost would seem not to be justified

Introduction and Objectives: This is a retrospective study on the treatment of lumbar degenerative disk disease (LDDD) using intervertebral arthroplasty. The lack of uniformity in the treatment of LDDD, persistence of pain even with solid fusion, and the possibility of changes over the fusion site have encouraged us to seek other solutions for this condition. Total intervertebral arthroplasty has been proposed as a possible alternative for selected cases of LDDD. Materials and Methods: Between November 1999 and July 2002, 16 patients with LDDD were treated surgically using third-generation total intervertebral arthroplasty (Link SB Charité III) with a chromium-cobalt alloy and ultra-high molecular weight (UHMW) poly-ethylene. Average follow-up time was 14 months (6-36 months), and average age was 42 years (35–52). There were 11 females and 5 males. All patients underwent radi-olographic studies, CT scan, MRI, and discography (minimum 2 levels). Indications included LDDD of one to three segments, absence of root tension signs, absence of complete disc collapse, and iconography including concordant discography. LDDD was primary in 11 cases and post-discectomy in 5 cases. Surgery was indicated when at least 6 months of conservative treatment failed to yield results. Blood loss and length of hospital stay were compared to a similar group that underwent posterolateral arthrodesis. Pain, function, and degree of disability were evaluated before and after surgery using GEER (1999) instruments for the evaluation of degenerative lumbar pathology. Increase in height of the posterior intervertebral space and segmentary lordosis were also measured. Results: Preoperative VAS: 7.8; postoperative VAS: 2.3. Disability index (Oswestry) was 41.3% preoperative and 10.8% postoperative. Average increase in height of posterior intervertebral space was 2.4mm, and mean segmental lordosis was 19.5°, which remained constant through the end of the follow-up period. Average hospital stay was 4.8 days (3–15) compared with 7.5 (5–18) for a group of patients who underwent suspended arthrodesis of L4–L5 with a much smaller quantity of blood loss. No infections were found. Complications: One patient developed an epidural haematoma, which was treated conservatively. Another developed a postoperative retroperitoneal haematoma, which was also treated conservatively. In neither case was there an adverse effect on the outcome of the procedure. One patient showed malpositioning of the prosthetic components on follow-up radiographs, with poor clinical progression at one year postoperative. The patient was treated with posterolateral fusion and right L5 foraminotomy. No infections were seen. Discussion and Conclusions: Treatment of LDDD with intervertrebral arthroplasty was shown to be effective in the short term, if strict guidelines are followed. Aggressive surgical management is highly inferior to conventional arthrodesis. A longer follow-up period is needed to confirm the validity of this treatment. Technical error in malpositioning of the components in one case caused a poor result

Purpose of the study: The endoscopic transforaminal approach to the lumbar disc proposed by A.T. Yeung has achieved world-wide acceptance. The Yeung endoscopic spinal system (YESS) used with a specific instrument set enables direct magnified optical control of discectomy performed under local anesthesia and neurolepanalgesia in the outpatient setting. We began our experience in 2003 and report here the results obtained in a consecutive series of 100 patients reviewed retrospectively. Material and methods: The inclusion criteria were patients with lumbar disc herniation-related lumbosciatic or crural pain non-responsive to well conducted medical care (including epidural or periradicular injections) for at least three months. The patients also had to display a concordant clinical and radiographic picture with confirmation of the symptomatic level by discography. Exclusion criteria were: excluded herniation with a fragment which had migrated into the canal; caudia equina syndrome; lower limb paralysis with muscle force scored less than 3; advanced-stage degernerative central bony stenosis affecting the clinical expression; pregnancy. The levels treated were: L3–L4 (n=6), L4–L5 (n=72), and L5–S1 (n=22). Herniation was forminal and extraforaminal in 53 cases, posterolateral in 31, and median in 16. There was an associated constitutional central stenosis in ten cases and in thirteen others, herniation was a recurrence after conventional surgery. Results: One hundred patients were reviewed at mean 18 months (range 12–34 months) follow-up. There were no serious neurological, vascular, or infectious complications. According to the McNab criteria outcome was good for 71 cases, fair for 16 and poor for 13 with 11 requiring revision with conventional surgery. Patients with foraminal and extraforminal herniation accounted for more than half of our series and responded best to treatment (84.9% good outcome) compared with posterolateral herniation (48%) (p< 0.05). Patients with median herniation had an intermediary outcome (68% good results). The least satisfactory outcome was observed at the L5–S1 level (63% fair and poor outcome), but the difference did not reach statistical significance compared with the higher levels. In patients with recurrent herniation after conventional surgery, there were four cases of failure. Discussion: These results are less satisfactory than those found in the literature. This might be explained by the less satisfactory outcome obtained with posterolateral herniations, probably because more than halve had migrated, generally above the plane of the disc, which in our experience cannot be accessed via the transforaminal approach. In addition, comparison of our first 50 cases with the last 50 showed an improvement in outcome to a mean 82%, expressing a learning curve for this type of technique. The most frequent error early in our experience was to insert the working endoscopic canula too anteriorly compared with the disc. The point of insertion must be very lateral determined by the discography in order to enter at least 30° posterior to the posterior part of the disc. Progressive fine-tuning of patient selection also helped improve outcome. YESS improves the work of the intradiscal instruments which can be control by direct view, explaining the the better results compared with the older mechanical or automatic (blind) methods. YESS is a very effective alternative to chemonucleolysis since papaine is no longer available. Compared with other endoscopic techniques for disectomy via an interlaminar approach, YESS offers the possibility of treatment patients in an outpatient setting with a local anesthesia. In addition the quality of the visual control of the foramen is better. These methods can be used in association with intradiscal Holmium-Yag laser which can also be applied to the bony walls of the foramen for a widening foraminoplasty. This transformainal endoscopic approach also offers a way to perform an exclusively foraminoscopic spondylodesis using an intersomatic cage. Conclusion: YESS is an excellent technique for non-migrated subligament posterolateral foraminal and extraforaminal herniations where conventional access to the foramen is known to be very difficult

The management of discogenic pain continues to be controversial. The results for operative and non-operative management are variable. This study aims to look at the results of interbody fusion versus dynamic stabilisation in patients with discogenic pain. Diagnosis was made by use of MRI and provocative discography. All patients had pre-operative Visual Analogue Scores and Oswestry Disability Index scores. Patients were then assessed in the post-operative period at 6 months, 1 year and 2 years. Case matched series with 19 patients in each group with a mean follow-up of 24 months. In comparison of both techniques there were no statistically significant differences but the dynamic stabilisation group had improved outcomes with both measures. The results did raise some further issues, as several patients in each group were either worse or had no significant improvement following surgery. In conclusion this paper raises concerns regarding the use of surgery for patients with discogenic pain. If surgery is however considered, dynamic stabilisation is a valid alternative to interbody fusion

To assess the effectiveness of dynamic stabilisation as a treatment for discogenic pain compared to standard treatment of interbody fusion. All patients were referred for a 2 year back-pain management programme. Patients with continued pain following conservative treatment underwent discography & MRI. Patients with painful degenerate discs on the above investigations were selected. Patients underwent interbody fusion (PLIF/TLIF) or dynamic stabilisation. Mean follow-up was 24 months with a minimum follow-up of 12 months. All patients had pre-operative ODI and VAS scores. Patients were then sent further questionnaires at 6 month intervals. The mean improvement in ODI following dynamic stabilisation was 20% (-20% → 56%), the mean improvement in the pain score was 2.4 (0→8). The mean improvement in ODI following interbody fusion was 11% (-14%→48%), the mean improvement in the pain score was 2.6 (-4→9). 10 patients in the dynamic stabilisation group had a greater than 20% improvement in ODI, 7 patients in the interbody fusion group had similar results. The above results demonstrate that dynamic stabilisation is at least as effective at treating discogenic pain as interbody fusion. The results however do question the validity of either interbody fusion (PLIF/TLIF) or dynamic stabilisation in the management of discogenic pain

Objective. To assess the effectiveness of dynamic stabilisation as a treatment for discogenic pain compared to standard treatment of interbody fusion. Study Design & Subjects. All patients were referred for a 2 year back-pain management programme. Patients with continued pain following conservative treatment underwent discography & MRI. Patients with painful degenerate discs on the above investigations were selected. Patients underwent interbody fusion (PLIF/TLIF) or dynamic stabilisation. Mean follow-up was 24 months with a minimum follow-up of 12 months. Outcome Measures. All patients had pre-operative ODI and VAS scores. Patients were then sent further questionnaires at 6 month intervals. Results. The mean improvement in ODI following dynamic stabilisation was 20% (-20% → 56%), the mean improvement in the pain score was 2.4 (0→8). The mean improvement in ODI following interbody fusion was 11% (-14%→48%), the mean improvement in the pain score was 2.6 (-4→9). 10 patients in the dynamic stabilisation group had a greater than 20% improvement in ODI, 7 patients in the interbody fusion group had similar results. Conclusion. The above results demonstrate that dynamic stabilisation is at least as effective at treating discogenic pain as interbody fusion. The results however do question the validity of either interbody fusion (PLIF/TLIF) or dynamic stabilisation in the management of discogenic pain

Persistent back pain in the presence of an intact posterior fusion is commonly seen and is often regarded as being psychogenic in origin. This paper discusses five patients, all of whom were chronically disabled by such pain; all five had a confirmed posterior and/or lateral fusion. In each case lateral discography identified the disc within the fused segment as the source of symptoms and pain relief was obtained with an anterior interbody fusion. This source of pain should be considered as a possibility in similar cases of failed back surgery

Introduction: We report the outcome two years following Dynesys for the treatment of Spinal Canal Stenosis. In both the FDA trial and the European multicentre study, stenosis was invariably combined with decompression, invalidating conclusions on the results of Dynesys alone. Method: Eighteen patients had symptomatic Spinal Canal Stenosis with root claudication sufficient to justify surgical intervention. Average age of patients was 68 with a range between 44–86 years. Dynesys was applied for the treatment of a single level in 4, two levels in 8, and more than two levels in 6. Patients were evaluated preoperatively using ODI, SF36, VAS, plain x-ray, MRI scanning & discography. Questionnaires were evaluated at the first and second years. Results: 2 patients had undergone previous spinal decompression, and decompression at the time of Dynesys surgery in 7. In the remaining 9 cases, no decompression was used, relying on distraction alone as in the X stop system. In this latter group, stenotic symptoms failed to resolve. Removal of Dynesys was indicated in 3 (16.6%). Discussion & Conclusions: Dynesys alone is not recommended as a treatment for symptomatic spinal stenosis. A separate study is required to address the question of whether Dynesys adjunct improves the back pain outcome compared with decompression alone

Objectives: The purpose of this study was to assess the effect of different types of posterior stabilisation on the fusion rate of anterior lumbar interbody fusion (ALIF). Thin section CT scanning has shown a higher rate of pseudarthrosis with ALIF than previously reported with standard radiological modalities. Cadaveric studies have demonstrated that posterior stabilisation would increase stiffness of the motion segment and is likely to enhance the rate of fusion with ALIF. The results of thin section CT scanning of ALIF, with and without posterior stabilisation, has not been reported previously. Methods: Patients with discogenic back pain confirmed by discography underwent ALIF surgery as a stand alone procedure or with posterior stabilisation – using trans-laminar screws, unilateral pedicle screws or bilateral pedicle screws. Patients were followed up prospectively and thin section CT scanning was used to assess inter-body fusion. Results: The fusion rate for stand alone ALIF was 51%, for patients with supplementary stabilisation with trans-laminar screws 58%, with unilateral pedicle screws 89% and with bilateral pedicle screws 88%. When ALIF was combined with pedicle screw stabilisation a significant difference in the fusion rate was found (p< 0.01). Conclusion: The addition of pedicle screw fixation at the time of ALIF produces a significant increase in the rate of interbody fusion

Introduction: The results of the FDA trial for Dynesys stabilisation implied that the procedure was effective as a method of treatment for this condition. However, all the American cases had adjunct decompressive treatment. In this study we report the outcome of the first two years following DYNESYS for Spondylolisthesis in two groups of patients; Dynesys alone and Dynesys with fusion. Method: Fifty five patients had Dynesys for symptomatic Spondylolisthesis which was indicated for surgical treatment. Average age for group 1 was 51 years with range of 36–85 years whereas in group 2, average age was 59 years with range of 31–79 years. Patients were evaluated preoperatively using ODI, SF36, VAS, plain x-ray, MRI scanning & discography. 33 of the patients underwent Dynesys alone (group 1) while 22 underwent dynesys with fusion (group 2). Previous decompression surgery was noted in 10 in group 1 and 8 in group 2. Results: In the first year following Dynesys, both groups did show significant improvement in all the four parameters; VAS (back and leg), ODI and SF36. In group 2 slight deterioration was noted in year 2 and while group 1 continued to improve, Subsequently 3 group 1 patients underwent fusion and 12 required removal/revision of Dynesys (40%). Discussion & Conclusions: Dynesys alone in the treatment of spondylolysthesis resulted in a 45% re-operation rate, and we believe it should not be recommended as an indication

Thirty-three patients who had undergone anterior cervical fusion for degenerative disc disease were reviewed to determine the efficacy of the procedure. Only patients who were available for examination and who had undergone operation at least one year previously were included in the review. Nearly all had had arm pain and three-quarters neck pain. Diminished neck movement and neurological abnormalities in the arms had been frequent findings. Diagnosis from the clinical features and plain radiographs is described. Myelography was not used routinely and discography was not used at all. Indications for operation and surgical technique are described. Results show that pain in the neck and arm was relieved in a high proportion of cases and that the neurological abnormalities often recovered. It is concluded that this operation is safe and has a definite place in the relief of pain from cervical disc degeneration resistant to conservative treatment

Introduction. We report the outcomes of minimally invasive technique for posterior lumbar interbody fusion (PLIF) procedure using Hollow Modular Anchorage (HMA) screws supplemented by routine pedicle screw fixation (Dynesis). Patients and Methods. Seventy-nine patients, who had undergone PLIF procedure using HMA screws supplemented by pedicle screw fixation, were included. Patients deemed suitable for surgery following discography under sedation, with Marcaine instillation establishing reducibility of the listhesis and temporary relief of symptoms. Clinical outcome included visual analogue scale scores for leg pain and back pain, Oswestry Disability Index (ODI) and SF-36 questionnaires. Results. Average age was 59 (range: 27-85). Mean follow- up was 5 years (range: 1-10). All cases went into union. None were lost to follow-up. Average length of stay was 24 hours (18-72 hours). All clinical parameters improved except SF-36. Mean ODI improved from 54 (range: 44-89) preoperatively to 33 (17-55) postoperatively (statistically significant, p=0.004). Back pain relief improved in visual analogue scale from average of 68 (range: 60-100) preoperatively to 37 postoperatively (range: 8:46) (statistically significant, p= 0.022). Leg pain relief improved from 53 (range: 31-100) preoperatively to 28 postoperatively (range: 4:60) (statistically significant, p= 0.007). Although mean SF-36 score improved from 37 (range: 10-41) preoperatively to 47 (range: 53-94) postoperatively (statistically insignificant, p=0.592). Complications included: one infection required removal of implant; two temporary motor weaknesses related to L5 nerve root; four required removal of the pedicle screw due to pain or loosening. Discussion. Our results are encouraging. Interbody HMA screws are porous hollow titanium screws with favourable biomechanical characteristics. Rather than square cages, they permit accurate placement of implant. Dynesys offers the option of extension and flexible support for the adjacent segment. Conclusion. PLIF supplemented with pedicle fixation is a reliable and safe procedure for degenerative spondylolisthesis. SF-36 is less sensitive for assessing spinal surgery outcome

Background: Spinal fusion for degenerative disc disease remains a controversial issue due to adjacent segment disease. Several alternatives have been evaluated; including Dynamic Neutralisation System for Spine and artificial disc arthroplasty. In our cohort study, we are highlighting advantages of DYNESYS over TDA and fusion as being a simple and reversible procedure if removal of implants is necessary. Materials and Methods: Prospective cohort study on 415 patients underwent DYNESYS. The implant has to be removed in 43 patients. Patients were evaluated preoperatively using Oswestry Disability Index, SF 36 and Visual Analogue Scores together with plain imaging and MRI scanning. Preoperative discography was performed in 81% of patients. Questionnaires were evaluated on subsequent follow up at 3 & 6 months, 1 year then at annual intervals. Results: Average treatment period was 26 months with a range from 3/12 to 60/12. The main reason for DYNE-SYS removal was screws’ failure or loosening followed by infections. The implant was used to treat single disc space in 20.9%, two spaces in 67.4% and three disc spaces in 9.3%. 81% of the screws were not Hydroxy-appetite coated. No loosening was detected among HA coated screws. Outcome assessment revealed significant improvement in SF36 even after removal of stabilising system while no worsening of ODI or VAS in comparison with preoperative status. Conclusions: DYNESYS can maintain disc height and restricts movements exceeding physiological limits. HA coated screws have superior biomechanical characteristics in preventing screw loosening and subsequent spinal spasms. If necessary, removal of implants is a simple procedure

Background: Spinal fusion for degenerative disc disease remains a controversial issue due to adjacent segment disease. Several alternatives have been evaluated; including Dynamic Neutralisation System for Spine and artificial disc arthroplasty. In our cohort study, we are highlighting advantages of DYNESYS over TDA and fusion as being a simple and reversible procedure if removal of implants is necessary. Material & Methods: Prospective cohort study on 415 patients underwent DYNESYS. The implant has to be removed in 43 patients. Patients were evaluated preoperatively using Oswestry Disability Index, SF 36 and Visual Analogue Scores together with plain imaging and MRI scanning. Preoperative discography was performed in 81% of patients. Questionnaires were evaluated on subsequent follow up at 3/12, 6/12 then at annual intervals. Results: Average treatment period was 26 months with a range from 3/12 to 60/12. The main reason for DYNE-SYS removal was screws’ failure or loosening followed by infections. The implant was used to treat single disc space in 20.9%, two spaces in 67.4% and three disc spaces in 9.3%. 81% of the screws were not Hydroxy Appetite coated. No loosening was detected among HA coated screws. Outcome assessment revealed significant improvement in SF36 even after removal of stabilising system while no worsening of ODI or VAS in comparison with preoperative status. Conclusions: DYNESYS can maintain disc height and restricts movements exceeding physiological limits. HA coated screws have superior biomechanical characteristics in preventing screw loosening and subsequent spinal spasms. If necessary, removal of implants is a simple procedure

Anterior lumbar interbody fusion (ALIF) is an accepted surgical treatment for disabling discogenic pain. Additional posterior fixation has been advocated. This is a prospective clinic al study evaluating a stand-alone anterior fusion cage with an integrated titanium plate and four divergent locking screws. Patients who had failed conservative management for lumbar discogenic pain were recruited into the study. All underwent diagnostic discography. Surgery was performed through an anterior retro-peritoneal approach. The fusion cage was packed with autogenous bone graft. Outcome measures included: Visual Analogue Scores (VAS), Oswestry Disability Index (ODI) and SF-36 data. Fine-cut CT was performed at one and two years post-operatively. Fusion was defined as continuous bony trabeculae joining the vertebral bodies. Fifty levels were operated on in 39 patients with a mean age of 40.8 years (22–55). The mean operative time was less than 120 minutes, and mean blood loss less than 100 mls. Radiographic fusion at one year was 78% and 100% at two years. Two year mean VAS sc ores for back pain improved from 7.0 to 3.7 (p< 0.01) and for leg pain from 6.1 to 3.1 (p< 0.01). The mean ODI scores decreased from 50.7 to 31.7 (p< 0.01), and SF-36 (PCS) scores increased from 28.4 to 37.5 (p< 0.01). There were no major complications and no patients have required supplementary posterior fixation. This technique is safe and is as effective as 360° fusion in achieving fusion in the management of discogenic back pain over one and two levels. This technique has the advantage of avoiding the morbidity associated with additional posterior fixation

Purpose And Background: In patients with chronic low back pain (LBP), selective injection procedures (provocative discography, medial branch, facet and sacroiliac joint blocks) have shown the pain source to be the intervertebral disc in 40%, the sacroiliac joint in 13–19% and the facet joints in 15–40%. No individual features in the history or examination are of consistent discriminatory value in diagnosis. This study aimed to assess whether patients with different pain sources could be differentiated using the Oswestry Disability Index (ODI) (a validated patient questionnaire scoring ten different aspects of pain and function in patients with LBP; higher scores correlating with greater disability). Methods And Results: ODI scores were recorded from 67 patients (46 female, age 17–82) whose source of LBP was subsequently confirmed by selective injection. The scores for each section of the ODI were compared between patients grouped according to pain origin; disc (n=11), sacroiliac (n=31) or facet (n=25). Patients with disc pain had significantly greater overall disability and scored higher for sitting, sleeping and social activity than those with facet or sacroiliac pain as judged by the 95% confidence limits of the median (p< 0.05). Patients with facet pain scored higher for walking and standing compared to those with sacroiliac pain. For disc pain scores were higher for sitting and standing than for walking, and for facet pain scores were higher for standing than for sitting or walking. Conclusion: Although the ODI is not a diagnostic tool, analysis of its components reveals characteristic pain and disability patterns in patients sub-grouped according to pain source

Aim: To investigate the use of the Graf Dynamic Stabilisation System for the treatment of multi-level discogenic pain associated with symptoms of ‘instability’. Introduction: Indications for the use of the Graf Ligament system remain controversial. There is a small group of patients who present with severely disabling pain with failed conservative treatment, of discogenic origin at more than one level, and associated with symptoms of so-called ‘instability’ (acute pain related to position and movement), for whom treatment is extremely difficult. Methods: Twenty-two consecutive adult patients of working age with this clinical picture, with discogenic pain at two or three levels confirmed by discography, were treated with the Graf Ligament System. They were prospectively studied, and reviewed by an independent assessor. Results: At an average of three year follow up, 50% had good or excellent results including return to work, 18% fair, and 32% were no better. None were worse. Correlation with pre-operative MRI findings and complications will be discussed. Conclusions: Whilst such dynamic systems may have a role in the treatment of discogenic pain, the success rate in this series does not justify its continued use for this indication without further research into the theoretical basis of the action of such dynamic stabilisation systems and the entry of all cases into prospective controlled trials

Primary disc space infections are thought to occur in children because of the abundant vascularity of the disc prior to skeletal maturity, and while they generally resolve with treatment, little is known about the long-term consequences on the spine. An ovine model of discitis was used to investigate the effects of discitis on spinal development in the growing sheep. Six-week-old lambs underwent lumbar discography at multiple spinal levels using either radiographic contrast inoculated with Staphylococcus epidermidis (inoculated group) or radiographic contrast only (control group). Plain x-rays of the spines were taken at intervals up to 18 months before the animals were killed and the spines removed for histologic and morphometric analysis. Discs from animals in the control group were radiologically and histologically normal at all time points, and as expected there was a steady increase in vertebral body and disc dimensions. Although not all inoculated animals showed histologic evidence of discitis, disc abnormalities were evident from an early stage. In particular disc height was significantly reduced from 2 weeks after inoculation and vertebral body dimensions were significantly reduced from one year. Infection of discs at a young age, whether or not it progresses to discitis, has a significant effect on spinal development

The multiplicity of factors that influence the clinical evolution of discopathies, determine a great diversity in its presentation. The barely known genetic predisposition, the individual morphological aspects, the age and sex, the associated co-morbidities as well as the patient environment define in its all an individual context that influences decisively the treatment for each patient. On the other hand, the identification in each case of the different stages of the multilevel DDD, causes doubts regarding the involvement of each segment in the respective clinical condition. To singly identify all sources of pain, and not only each painful level, is the main challenge poised to the spine surgeon when defining the treatment strategy. The diagnosis aggressiveness must be proportional to its doubts, and the discography, the disco-scanner and the facet blocks are fundamental when the conventional clinical investigation is inconclusive. The use of minimal invasive techniques such as IDET or Coblation can be considerate as alternatives, especially in the early stages of single-level DDD. The nucleoplasthy – nuclear prosthesis- is an interesting alternative in the intermediate stages of the discogenic pain DDD, as well as in the predominant facet pain or in the foraminal dynamic stenosis is the dynamic stabilization. Those are techniques with controversial results and which liability in some cases is yet to be proven. Last, the use of different techniques in different levels in the context of multi-level DDD – ex: fusion + disc replacement; disc replacement + dynamic stabilization with or without decompression procedures in the spinal canal- must be rigorously considered according to the specific dysfunction of each segment and considering the anatomical and functional reconstruction of the spine

The fourth lumbar vertebrae and L4-5 discs from six cadaveric lumbar spines were subjected to detailed strain gauge analysis under conditions of controlled loading. With central compression loads, maximal compressive strain was found to occur near the bases of the pedicles and on both superficial and deep surfaces of the pars interarticularis, which emphasises the importance of the posterior elements of lumbar vertebrae in transmitting load. Radial bulge and tangential strain of the disc wall were maximal at the posterolateral surface, in agreement with the fact that disc degeneration and prolapse commonly occur there. Under posterior offset loads simulating extension, both compressive and tensile strains were found to be increased on both surfaces of the pars interarticularis, which suggests that hyperextension may lead to stress fractures and spondylolisthesis. Posterior offset loads also increased the radial bulge of the posterior disc wall and tangential strain at the anterior surface of the disc. Anterior offset loads simulating flexion increased the radial bulge of the anterior disc wall and tangential strain at the posterior surface of the disc. These findings are compatible with movement of the nucleus pulposus within the disc during flexion and extension. This hypothesis was supported by post-mortem discography

Background: Back pain in adult patients with a pars-interarticularis defect may be due to movement at the defect or abnormal inter-segmental movement at the adjacent degenerate disc. The suggested treatment of segmental fusion may not be necessary, if the defect alone was source of pain. We hypothesize that the defect may be the only source of pain in certain adults, even if the MRI scan shows an abnormal disc. Objective: To form a protocol of management in adults with pars defect and adjacent level disc degeneration. To study the results of primary lysis repair using ‘AO Morscher clamp’ in patients with ‘spondylolysis’ or ‘Grade 1 ‘spondylolisthesis’. Methods: This is a prospective study involving adults with ‘spondylolysis’ or ‘Grade 1 ‘spondylolisthesis’ not responding to conservative management and requiring interventional treatment. We investigated this subgroup of patients with lysis block and discography. On this basis, of a total of ten patients, seven were offered lysis repair and bone grafting using ‘Morscher’s clamp’; three were offered spinal fusion. Outcome was assessed using Visual Analogue Score (VAS) and Oswestry Disability Index (ODI) done pre-operatively and six months post-op. Results: Out of ten patients (28 to 45 years; 4males and 6 females), seven patients underwent primary lysis repair using ‘AO Morscher clamp’. Union of pars achieved in all the patients by 4 months (Follow-up 4 months to 2 years). Three underwent fusion. Mean VAS improved from 7.2 to 1.2 in lysis repair group. Mean ODI improved from 68 % to 24%. All patients had full range of spinal movement postop. Conclusion: A thorough pre-operative workup of patients with pars defect and adjacent level disc degeneration showed that pain is due to the pars defect in 70% of our cohort. This subgroup of patients could successfully be treated with ‘lysis repair’ rather than a more morbid procedure of ‘spinal fusion’

Defects in annulus fibrosus induced by needle puncture can compromise mechanical integrity of the disc and lead to degeneration in animal models. This study examined the immediate and short-term mechanical and biological response to annulus injury through needle puncture using small and large gauge needles in a bovine organ culture system. Bovine caudal intervertebral discs were harvested, assigned to one of two needle puncture groups (small = 25G, N=11; large = 14G, N=12) or an unpunctured control group (N=10), and cultured in organ culture for 6 days. After measuring initial heights, diameters, and wet weights, discs were placed in an organ culture chamber and incubated with constantly circulating media in standard culture conditions under a 0.2 MPa static load. Discs underwent a daily dynamic compression loading protocol for five days from 0.2 – 1 MPa at 1 Hz for one hour. Disc structure and function were assessed with measurements of dynamic modulus, creep, height loss, water content, proteoglycan loss to the culture medium, cell viability and histology. Needle insertion caused a rapid decrease in dynamic modulus and increase in creep during one hour of loading, although no changes were detected in water content, disc height, or proteoglycan lost to the media. Cell viability was maintained except for localised cell death at the needle insertion site. An increase in cell number and possible remodelling response was seen in the insertion site in the nucleus pulposus. Relatively minor disruption in the disc from needle puncture had immediate and progressive mechanical and biological consequences with important implications for the use of needle puncture in discography, and repair/regeneration techniques. Results also suggest diagnostic techniques sensitive to mechanical changes in the disc may be important for early detection of degenerative changes in response to annulus injury

Objective A prospective longitudinal study with a mean 22 month follow up (range 6–36 months) to assess the outcome of patients with chronic discogenic lumbar back pain who underwent intradiscal electrothermal therapy (IDET). Method Patients with a discogenic origin of their back pain confirmed by diagnostic imaging and discography and who underwent IDET were included in the study. Discographic reproduction of symptoms with subsequent abolition with local anaesthetic led to inclusion in the study regardless of discogram volume. Outcome was assessed using VAS pain scores, Oswestry Disability Index (ODI) scores, employment status, subjective outcome and pain diagrams. Results 68 patients were treated with IDET. 51 patients were successfully followed up for a minimum of one year, of whom 31 had at least 2 year follow up. These patients were divided into two groups. Group 1 consisted of 29 patients aged less than 40 with single level disease, no facet joint arthritis, a low volume positive discogram and an organic pain diagram. Their mean VAS scores decreased from 7.52 to 3.84 (p< 0.001). 70% reported a good or excellent outcome with only 30% fair or poor. Group 2 included the remaining 22 patients. Their mean VAS decreased from 7.41 to 6.13 and only 32% reported a good or excellent outcome with 68% fair or poor. Conclusion We conclude that with very strict selection criteria, IDET can have a successful outcome

Study Design: Prospective study with a 2-year follow-up. Background: Intradiscal electrothermal therapy (IDET) was developed as an intermediate stage between conservative measures (analgesia, physiotherapy and injections) and radical surgery (fusion and disc replacement) for the treatment of internal disc disruption (IDD). Recent reports have questioned the efficacy and safety of this treatment. Objective: To assess the long-term outcome of patients with discogenic low back pain (≥ 6 months duration) treated with IDET who had previously failed to improve with nonoperative treatment. Methods: Forty patients with IDD determined by pre-operative provocative discography and MRI were treated with IDET. VAS pain scores, SF-36 scores, analgesic usage and sitting tolerance (mins) were collected pre-treatment and at 12 and 24 months. Subsequent treatments were recorded. The differences in the outcome scores were tested by Wilcoxon signed rank tests. Results: Average age was 46 years (range 25–62 years) with 44% males and 56% females. No significant improvement was seen in pain intensity as measured by VAS and bodily pain SF-36 scores pre treatment and at 12 and 24 months post IDET. There were no significant differences in the remaining SF-36 subscales. Only 11% used less pain medication. Sitting tolerance improved between pre and 1-year post IDET, the difference was not significant. Eight (20%) patients underwent further surgery; 5 disc replacement and 3 fusions at 1-year post treatment. Conclusion: The patients with IDD did not show any improvement at 1-year or 2-year post IDET. A significant proportion of patients required further surgery. We believe that the efficacy of IDET is doubtful

Introduction The Dynesys device uses transpedicular screws linked by a cord and spacers. It is claimed that the advantage is that it allows some motion, in all directions, in the operative levels. In vitro laboratory biomechanical studies show that the movement permitted is similar to rigid fusions. This study measures the changes in the lumbar spine in different postures, pre- and after insertion of the device. Material-method In our study 20 patients with dominant low back pain, with or without leg pain, were treated with Dynesys system. Stress discography was made to evaluate the symptomatic level. All had a positional MRI preoperatively and nine months post-operatively in flexion-extension-lateral bending. The patients were divided in to two groups:. Group(A) with 8 patients in which Dynesys was used with fusion (disc-height< 40 %). Group(B) with 12 patients was the Dynesys-only group (disc-height=40–90%). Results The operated levels were 42, 10 of those were fused levels. The results showed that there was a statistically significant difference in flexion-extension range of movement of the whole lumbar spine (mean= −13.45)(p< 0.005), but it wasn’t significant in the level above (mean=0.056)(p=0.972) and at a single instrumented segment was (mean=−4.06°)(p< 0.05). The changes in the anterior disc height was (mean= −1.18)(p< 0.05) and to the posterior (mean=0.37)(p=0.134). In bending were (mean=−0.87°)(p=0.18) for left and (mean=−0.24°)(p=0.75) for the right. Discussion This study shows that in the Dynesys stabilizing system allows small range of movement at the instrumented levels, with no significant increased mobility in the adjacent levels. Also the device acted to compress the anterior annulus

Introduction: Although several studies have reported on outcomes following heating of annular tears with a thermo-resistive catheter (SpineCATH), little data is available on the efficacy of thermal treatment with a flexible radiofrequency electrode (discTRODE). The aim of this prospective case-control study was to determine the efficacy of radiofrequency heating of painful annular tears in the lumbar spine. Methods: After at least six months of conservative treatment, 46 patients were studied for the presence of single level painful annular tears with MRI and provocative discography. Thirty-one patients underwent heating of their annular tears with a flexible radiofrequency electrode placed across the posterior annulus. The remaining fifteen patients continued with conservative management and acted as a control group. At present, 22 patients have been studied at 18 months follow-up and the remainder including the control group for a minimum of one year. The Visual Analogue Scale (VAS), the Oswestry Disability Index (ODI) and the Medication Quantification Score (MQS) were obtained before and at three monthly intervals after treatment. Results: VAS decreased significantly after the radio-frequency treatment, and this decrease persisted at 18 months follow-up. The VAS did not change over 18 months in untreated controls. The decrease in VAS was significantly greater in the treated patients than the controls. The ODI also decreased in treated patients but did not change in controls. The MQS did not change in either group over the 18-month follow-up period. Discussion: Radiofrequency heating of annular tears can lead to an improvement in the pain and disability of internal disc disruption. The improvement gained by this treatment method is significantly better than conservative management

Purpose: To report the clinical and radiographic prospective results of a consecutive series of patient with a minimum two year follow-up with the Charite Total Disc Arthroplasty (TDA). Method: Between 2001 and 2005, sixty patients underwent a Charite TDA (Depuy Spine, Raynham, MA) at either L4-5 or L5-S1. The primary indication for surgery was discogenic low back pain confirmed by provocative discography. Clinical assessment was carried out preoperatively and postoperatively at 3, 6, 12 months, and once a year thereafter using the Oswestry Disability Index (ODI), Visual Analogue Scale (VAS) for back and leg pain, and SF-36. Radiographic analysis included: angle of sagittal rotation, translation of the rostral vertebra onto the caudal vertebra, anterior vertical motion (AVM), middle vertical motion (MVM), posterior vertical motion (PVM), pre- and post-operative lumbar lordosis, disc height and subsidence of the TDA. The radiographic measurements were performed using the GE Medical Systems Centricity PACS Software Version 1.0. Results: There were 36 female and 24 male patients with a mean age of 39 (range 21–59). The mean duration of low back pain was 70 months. Twenty-five percent claimed work compensation status. The mean postoperative hospital stay was 4.8 days. A statistical significant improvement was demonstrated between the mean pre-operative ODI (50) and all post-operative intervals (p< 0.0001) which had declined to 27.7 by one year. Similarly, pre-operative VAS back pain (8.0), leg pain (6.1), SF-36 physical component summary score (33.5) and mental component summary score (41.8) remained improved (p< 0.0001) by three months (4.1, 3.1, 51.7, 62.0 respectively). One patient with an L5-S1 TDA has since undergone a posterolateral instrumented fusion. The mean pre- and post-operative lumbar lordosis was 34.58 and 53.48 respectively. The mean saggital rotation was 6.5 degrees at 5 year follow-up, while the mean translation was 0.83 mm. The mean AVM, MVM and PVM were 0.59 mm, −3.96 mm and 3.69 mm respectively at 5 year follow-up. Conclusion: This study demonstrates satisfactory clinical results in carefully selected patients. The radiographic assessment confirmed preservation of movement at the replaced disc during flexion and extension of the lumbar spine

To compare the effectiveness of ALIF, using the Hartshill Horseshoe cage, and Graf ligamentoplasty for stabilisation of comparable severity of degenerative disc disease. Between 1995 and 1997, 27 patients who had single level ALIF with Hartshill Horseshoe cage [group A], and 28 patients who had single level Graf ligamentoplasty [group B] were assessed by Oswestry disability index, a subjective score, Zung Depression Scale [ZDS], and Modified Somatic Perception Questionnaire [MSPQ]. The two groups were similar in age and sex distribution. The patients were randomized, and procedures were all undertaken primarily for symptoms of back pain, although some patients in each group reported some leg pain. No patients with the ALIF group had any MRI evidence of neurological compromise. Where there was any degeneration at more than 1 level, discography was undertaken (8 patients in each group) confirming an isolated pain source at a single level. The duration of back symptoms and leg symptoms in the two groups was similar. There was some difference in the distribution of the MRI grade of disc degeneration between the 2 groups, but this did not reach statistical significance. Following is the characteristic of the 2 groups:. In this group, Graf ligamentoplasty procedure had a statistically significant better outcome than ALIF with the Hartshill horseshoe cage. This may be due to the retention of some degree of normal mobility of the affected segments after stabilisation with Graf ligaments. However, at a minimum follow-up of 2 years, these represent only medium term results. There is a potential for a change in the outcome in the long term

Study Design: A retrospective cross sectional cohort study of degeneration of the lumbar spine, using pre- and post-discography MRI scans of 28 patients, as compared to two consecutive MRI scans of an age and sex matched control group of 32 patients. Objective: To determine whether injection of steroid into a lumbar intervertebral disc causes degeneration, as assessed by magnetic resonance imaging (MRI). Methods: Twenty-eight patients with chronic discogenic low back pain were selected. Each had been investigated with an MRI, discography (with intradiscal injection of methylprednisolone), and a post-discography MRI scan. A randomly selected control group of thirty-two age and sex matched patients, having been examined on two occasions with MRI, was established. Two interpreters blinded to the patient groups assessed the degree of lumbar disc degeneration on the MRI scans on two separate occasions, using the Pfirrmann grading system. Results: Kappa values proved interpretation consistency as compared with the published Pfirrmann paper. Variables of age and sex in the two groups showed no true variation in whether the discs improved, stayed the same or degenerated. The difference in the proportions for those with and without the injection gave a test statistic of 11.92 (p-value=0.002), indicating a discrepancy in the degeneration between those discs with and without an injection. Conclusion: Previous studies on intradiscal steroid injections have shown variable results. Animal studies have shown that steroid administered intradiscally causes degeneration and primary calcification in discs. Two prospective double blind clinical trials using intradiscal steroids identified no significant benefit or improvement in the clinical outcome. This study indicates that intradiscal steroid injections cause MRI visible disc degeneration. In association with the results of the clinical trials, this study questions the indications for the use of intradiscal steroids in the management of discogenic low back pain

Purpose of the study: Indications for disc prosthesis is generally established on the basis of the MRI findings (MODIC classification) and the discography. We considered that knowledge of the preoperative disc height is also important. We report a multicentric study of the results of lumbar arthroplasties as a function of preoperative height of the operated disc. Material and methods: A Mobidisc prosthesis was implanted in 93 patients and followed prospectively for at least one year (mean follow-up 5 years). Disc height was compared with the height of the suprajacent disc and divided into three groups: > 66% of height (GI) i.e. a subnormal disc height (n=30), 33–66% (GII) moderate impingement (n=36), < 33% (GIII) total impingement (n=27). A MODIC signal was found for 19% in GI, 42% in GII and 40% in GIII. Results: The lumbar VAS improved from 6.7 to 3.2 (GI), 6.2 to 2 (GII) and 6.2 to 1.5 (GIII). The radicular VAS improved from 4.8 to 3.1 (GI), 5.7 to 2.4 (GII) and 5.5 to 1.6 (GIII), respectively 69, 75 and 85.5% of the patients were satisfied or very satisfied for relief of the lumbar or radicular pain. The Oswestry score improved from 50 to 22% (GI), 49 to 20% (GII) and 46 to 12% (GIII). By MODIC, the lumbar VAS improved from 6.5 to 2.8 (MODIC 0) and from 6.6 to 2 (MODIC 1). The radicular VAS was improved from 5.5 to 2.9 (MODIC 0) and from 5.3 to 2.1 (MODIC 1). The Oswestry score was improved from 52 to 24% (MODIC 0) and from 48 to 15% (MODIC 1). Independently of MODIC, the VAS was always better for very tight discs and lower if the disc height was preserved. Discussion: An influence of the disc height was found for all parameters studied, irrespective of the type of disc disease as described by the MODIC classification. The presence of a tight preoperative disc height appeared as the essential prognostic factor for discal prostheses. For a MODIC 0 discopathy, without loss of disc height, only 67 and 61% of the operated patients were satisfied or very satisfied with relief of lumbar and radicular pain (VAS 3.6 and 3.4) for respectively 88 and 75% of the MODIC0 discopathies with discal impingement (VAS 1.5 and 1.5). Though it should not be formally ruled out, surgery for discopathy with a preserved disc height should be examined prudently before implanting a disc prosthesis

Aims: The aim of our study was assess the outcome following intradiscal electrothermal therapy in patients with chronic discogenic back pain. Methods: 57 patients underwent IDET. All patients had an MRI and provocative discography to conþrm that their pain was of disco-genic origin. Pre-IDET, patients completed: a pain visual analogue score (VAS), an employment assessment and a pain diagram. Post-IDET assessment included a VAS, a subjective outcome assessment, an SF36 and an employment assessment. Results: 46 (80.7%) patients with a mean age of 41.2 years (range 16–76) were successfully followed up. IDET performed at one level in 48 patients and at two levels in 9. The mean follow-up was 19 months (Range 12–32 months). There were 27 males and 19 females. There were no serious complications. The mean pain VAS was 6.6 pre-IDET and 6.3 Post IDET (not signiþcant). 54% of patients stated that they were either Ç much better È or Ç a little better È. Subgroup analysis suggests that neither the presence of mild facet joint arthritis nor undergoing IDET at more than one level has an effect on outcome. Ç Non-organic È preoper-ative pain diagrams (as assessed by principles described by Mann et al) had a signiþcant negative effect on outcome, with patients in this group having a having a deterioration in VAS from 6.75 to 8.3 and only 10% stating that their pain was Ç a little better È and none Ç much better È. Conclusion: We believe that our study demonstrates that IDET can achieve satisfactory results in the treatment of chronic discogenic low back pain, but that patient selection is important in achieving this outcome

Purpose Of The Study: This study measures the changes in the lumbar spine in different postures, pre- and after insertion of the device. Material-Method-Results: All the 25 patients, with chronic back pain, had discography preoperatively a positional MRI scans pre-op and nine months postoperatively in different postures. The patients were divided into two groups. The Group-A with 14 patients in which only Dynesys was used and Group-B with 11 patients in which Dynesys was combined with fused levels. The operated levels were 51, 13 of which were fused. The results showed that the mean range of movement of the lumbosacral angle reduced by 10.28° (Preop=39.21°, Postop=28.93°) (p=0.016) in group-A. In group-B it reduced by 13.73° (Preop=36.18°, Postop=22.45°) (p=0.02). The range of movement of the end plate angle at the instrumented segments in group-A reduced by 2.96° (Preop=5.56°, Postop=2.60°) (p=0.016) while in group-Bit reduced by 4.23° (Preop=6.69°, Postop=2.46°)(p=0.008). The mean range of movement of the end plate angle at adjacent level in group-A reduced by 1.58° (Preop=8.7°, Postop=7.21°)(p=0.427) while in group-B it increased by 1.73° (Preop=6.91°, Postop=8.64°) (p=0.149). The mean anterior disc height in group-A reduced by 1.18mm (Preop=10.05mm, Postop=8.87mm) (p< 0.005), and the posterior one was increased by 0.6mm (Preop=6.51mm, Postop=8.87mm) (p=0.013). In group-B, the anterior disc height was reduced by 1.11mm (Preop= 10.44mm, Postop=9.33mm) (p=0.049) and the posterior one by 0.16mm (Preop=6.98mm Postop=6.82mm) (p=0.714). Conclusion: Dynesys stabilizing system allows movement at the instrumented levels, with no significant increased mobility in the adjacent levels. Also the device acted to compress the more the anterior annulus than to distract the posterior

Surgical treatment of degenerative disc disease (DDD) has been widely modified in the last decade. The clinical evaluation of back pain has been improved by the use of functional scores and VAS. The discography is an adjunct for decision-making, but CT scan and MRI are the keys to evaluate the aging process. The conservative treatment with physiotherapy and exercise programs is always the first and very useful treatment. Percutaneous therapy like facets injection, laser, IDET, radiofrequency in the disc can be a solution in some specific cases. Their efficacy has been evaluated in different studies and is sometimes controversial but there aren’t contraindications for further treatment and their complication rate is low. Dynamic posterior stabilization devices using pedicular screws and ligament tension band are proposed to try to put the disc in rest and some histological analyzes confirmed this hypothesis. Interspinous devices have been evaluated since many years but there indications need to be established as the literature available doesn’t provide clear indication criteria. Partial disc replacement is a new challenge for DDD. Many devices have in clinical evaluation but only few have prospective studies demonstrating their efficacy. The PDN was the pioneer and as the other in the evaluation process it has to solve the problem of the stability of the device. The last products on the market are promising. The total disc replacement is the last solution before fusion. Many studies including prospective and randomized have demonstrated the efficacy of total disc replacement. The indication is the key point of success. The training to perform the approach safely is mandated. Finally the fusion: anterior, posterior or combined is the ultimate solution to treat DDD. This was the gold standard and is still the most widely used treatment. As a dead end fusion is used only if other solutions cannot be proposed or used. DDD therapy has to be considered with the help of an algorithm including all motion preservation treatment before fusion

A prospective series of patients undergoing intradiscal electrothermal therapy for treatment of lower back pain refractory to physiotherapy. 33 patients with a mean follow up of 16 months were assessed pre- and postoperatively at Mayday University Hospital between 1999–2001 using visual analogue scores and SF-36. These patients failed to show an improvement with physiotherapy and had no evidence of a significant disc prolapse according to MRI with their back pain being reproduced at one or more disc levels on provocative discography. All procedures were performed as day cases with a temperature of 90 degrees being reached in all patients. Baseline and follow-up outcome measures indicated the SF-36 mean improvement of pcs to be 7.05 (P< 0.001) and the mean improvement of mcs 10.05 (P< 0.001) following IDET with a mean change of 1.5 in the visual analogue score. Overall 25 patients reported a noticeable improvement in their back pain symptoms with 3 patients recording worsening symptoms and the other 5 patients remaining unchanged. Surgical complications included 1 breakage of the catheter within the patient and a disc prolapse at the level of surgery that required subsequent discectomy. 30% of patients were noted to have a temporary foot drop postoperatively which was due to inadvertently performing a lumbar plexus block on infusion of local anaesthetic before catheter insertion. There was no reported discitis, deep infection or nerve root injury. Patients with proven discogenic lower back pain that have not responded to physiotherapy have generally improved following IDET in this series. However, this improvement is not as dramatic as first indicated in preliminary studies and includes a small number of patients which noted a deterioration in their symptoms, one of which requiring a discectomy as a direct result of the procedure

Disc degeneration in the human spine is characterised by progressive fraying and dehydration of the nucleus pulposus associated with formation of clefts within the annulus fibrosus. These have been classified on the basis of autopsy studies into radiating, circumferential and peripheral tears (rim lesions). Outer tears allow neovascularisation of the outer third of the annulus fibrosus and ingrowth of nerve fibres. Correlation with discographic findings had suggested the relevance of peripheral defects in the pathogenesis of discogenic pain. Outer annular tears are likely to be linked to tensile strain onto the collagen fibres and, therefore, may have a mechanical aetiology. In the animal model, peripheral tears of the outer annulus were proven to induce degenerative changes within the inner annulus and the nucleus pulposus. The increased understanding of the role of discrete peripheral defects of the annulus in discogenic pain may support the potential therapeutic effects of thermal treatment using radiofrequency waves and specially designed probes. At present, however, no in vivo studies have been able to demonstrate healing of outer annulus defects and reversibility of mechanical lesions to the intervertebral discs by thermal therapy. While it is highly likely that discrete defects of the outer annulus may be responsible for acute episodes of self-limiting low back pain, it is unclear if annular pathology may be as relevant for chronic disabling back pain. Recent studies using discography and other semi-invasive techniques have suggested that the main discriminating factors between benign, self limiting and chronic disabling back pain may not be anatomical but psycho-social. The challenge remains, in the 21st Century as in the past, to devise appropriate strategies that may lessen the socio-economic burden of back pain. Surgery, however, is highly unlikely to play a significant role in the future

Purpose of study. To compare the cost and outcome of Intradiscal Elecrothermal Therapy (IDET) with fusion (anterior lumbar interbody fusion with posterior translaminar screws) at one year, in single level lumbar disc disease. Methods. 49 patients were prospectively enrolled for IDET. The 49 fusion group patients had either a Syncage or Femoral Ring Allograft. All patients had at least 6 months of LBP with single level disease on MRI or positive discography. Results. The two groups were demographically similar. Pre-treatment ODI, VAS and SF-36 for physical function were significantly worse in the fusion group (p< 0.05). At 1 year, IDET patients had clinically important improvement in ODI (47 to 37, p< 0.001), SF-36 pain (26 to 42, p< 0.001) and physical function (40 to 54, p< 0.001), with a significant drop in VAS (5.4 to 4.2, p=0.012). Fusion patients had clinically important improvement in ODI (54 to 44, p< 0.001) and SF-36 pain (25 to 37, p< 0.001) but not in physical function (32 to 39, p=0.08), with a significant improvement in VAS (7.2 to 5.7, p=0.001). Within 1 year, 11 patients in the IDET group had further interventions (4 nerve root blocks, 1 fusion, 2 disc replacements, 2 posterior interbody fusions) and 9 further procedures were carried out in the fusion group (2 epidurals, 1 facet injection, 4 wound washouts, 1 revision posterior instrumentation, 1 repair pseudomeningocoele). Cost per patient at 1year, including all secondary procedures, was £7,545 for fusion and £2,851 for IDET patients. Conclusions. Fusion is substantially more expensive than IDET with comparable clinical outcome

Purpose: To report the clinical and radiographic prospective results of a consecutive series of patient with a minimum two year follow-up with the Charite Total Disc Arthroplasty (TDA). Methods: Between 2001 and 2005 sixty patients underwent a Charite TDA (Depuy Spine, Raynham, MA) at either L4–5 or L5-S1. The primary indication for surgery was discogenic low back pain confirmed by provocative discography. Clinical assessment was carried out preoperatively and postoperatively at 3, 6, 12 months, and once a year thereafter using the Oswestry Disability Index (ODI), Visual Analogue Scale (VAS) for back and leg pain, and SF-36. Radiographic analysis included: angle of sagittal rotation, translation of the rostral vertebra onto the caudal vertebra, anterior vertical motion (AVM), middle vertical motion (MVM), posterior vertical motion (PVM), pre- and post-operative lumbar lordosis, disc height and subsidence of the TDA. The radiographic measurements were performed using the GE Medical Systems Centricity PACS Software Version 1.0. Results: There were 36 female and 24 male patients with a mean age of 39 (range 21–59). The mean duration of low back pain was 70 months. Twenty-five percent claimed work compensation status. The mean post-operative hospital stay was 4.8 days. A statistical significant improvement was demonstrated between the mean pre-operative ODI (50) and all post-operative intervals (p< 0.0001) which had declined to 27.7 by one year. Similarly, pre-operative VAS back pain (8.0), leg pain (6.1), SF-36 physical component summary score (33.5) and mental component summary score (41.8) remained improved (p< 0.0001) by three months (4.1, 3.1, 51.7, 62.0 respectively). The mean pre and post-operative lumbar lordosis was 34.58 and 53.48 respectively. The mean sagittal rotation was 6.5 degrees at 5 year follow-up, while the mean translation was 0.83 mm. The mean AVM, MVM and PVM were 0.59 mm, −3.96 mm and 3.69 mm respectively at 5 year follow-up. Conclusion: This study demonstrates satisfactory clinical results in carefully selected patients. The radiographic assessment confirmed preservation of movement at the replaced disc during flexion and extension of the lumbar spine. Interest Statement: No financial benefits or funding has been received for the completion of this study

Objectives: To evaluate the clinical and radiological outcome following anterior interbody fusion using a femoral cortical allograft packed in the centre with autogenous iliac graft combined with posterior pedicle fixation. Design: A prospective study of 30 consecutive adult patients diagnosed with lumbar degenerative disc disease. Summary of background data: Various fusion options have been described in the literature with various clinical and radiological outcomes. Narrowing of the disc space is thought to be the primary cause of all the potential secondary spondylotic changes; the ideal corrective surgery would be one that reconstitutes the disc space interval. A hybrid graft consisting of a femoral cortical allograft (FCA) ring packed in the centre with autogenous cancellous iliac graft seems to be an ideal option as one should capitalize on the mechanical strength of the cortical ring and the biological strength of the cancellous autogenous graft. Methods: 15 patients with failed back surgery, 15 patients with primary degenerative disc disease. Mean age was 43 years. All patients had preoperative radiographs, MRI scanning, discography was not used in this study. All femoral allografts were processed by freeze drying and sterilized using ethylene oxide. The protocol for surgery consisted of: . * Left sided retroperitoneal muscle splitting approach. * Anterior hybrid interbody grafting. * Pedicle screw fixation without grafting. Results: There were no complications from using the allograft. Intraoperative and postoperative complications were seen in 3 patients. After a minimum follow up of 2 years good clinical outcome was achieved in 83 % using Ricciardi et al criteria, solid fusion was achieved in 98%. Conclusion: The results in this study continue to support the efficacy of using hybrid interbody grafts to achieve a successful fusion, however there is discrepancy between the radiological and clinical outcome which merits additional investigations

Purposes Of The Study-Background Data: Dynesys is claimed that allows motion in the operative levels. This study measures the changes in the lumbar spine in different postures, pre- and after insertion of the device. Thirty patients with were treated with Dynesys system. All had discography and positional MRI preoperatively and nine months post-operatively. The patients were divided in to two groups. The first in which only Dynesys was used and the second in which Dynesys was used with fusion. Results: The operated levels were 63. The results of the pMRI measurements showed that the range of movement(ROM) of the L1/S1 angle in group-A reduced by 11.89. o. {pre-op=39.26. o. ,postop=27.37. o. (p=0.008)} while in group-B reduced by 13.73. o. {preop=36.18. o. ,po stop=22.45. o. (p=0.002)}. The ROM of the end plate angle at the instrumented segments in group-A reduced from 5.24. o. to 2.18. o. {difference 3.06. o. (p< 0.005)} and in group-B reduced from 6.69. o. to 2.46. o. ,{difference 4.23. o. (p=0.008)}. The ROM of the end plate angle at adjacent level in group-A changed from 8.26. o. to 7.0. o. {reduction 1.26. o. (p=0.388)},while in group-B increased from 6.91. o. to 8.64. o. , {difference 1.73. o. (p=0.149)}. The mean anterior disc height in-group A reduced by 1.43mm (p< 0.005) from 9.75mm to 8.32mm, and the posterior one was increased from 6.27mm to 6.77mm {difference of 0.5mm,(p=0.008)}. In group-B the anterior disc height reduced by 1.11mm (pre-op=10.44mm,post-op= 9.33mm,p=0.049) and the posterior one by 0.16mm (pre-op 6.98mm to post-op 6.82mm,p=0.714). Conclusion: This study shows that in the Dynesys stabilizing system allows small range of movement at the instrumented levels, with no significant increased mobility in the adjacent levels. Also the device acted to compress the anterior annulus

Study Design: Prospective longitudinal study with a 2-year follow-up. Background: Intradiscal electrothermal therapy (IDET) was introduced to bridge the gap between conservative measures (analgesia, physiotherapy and standard injection therapy) and radical surgery (disc replacement and fusion) for the treatment of internal disc disruption (IDD). Recent reports have questioned the efficacy and safety of this so called less invasive treatment technology. Objective: To assess the long-term outcome of patients with chronic discogenic low back pain (< 6 months duration) treated with IDET who had previously failed to improve with comprehensive nonoperative treatment. Methods: Forty patients with IDD determined by provocative discography and pre-operative MRI were treated with IDET. VAS pain scores, SF-36 scores, analgesic usage and sitting tolerance times (mins) were collected pre-treatment and at 12 and 24 months. Subsequent treatments were recorded. Statistical analysis was performed using Wilcoxon signed rank tests to test for differences in the outcome parameter scores. Results: Average age was 46 years (range 25–62 years) with 44% males and 56% females. The study group demonstrated no significant improvement in pain intensity as measured by VAS and bodily pain SF-36 scores pre treatment and at 12 and 24 months post IDET. There were no significant differences in the remaining SF-36 subscale scores at 0, 12 and 24 months after treatment. Analgesia requirement remained the same in 77% of the patients; 12% required stronger analgesia and only 11% used less pain medication. Although sitting tolerance improved between pre and 1-year post IDET, the difference was not significant. Eight (20%) patients underwent further surgery in the form of a disc replacement or fusion at 1-year post treatment. Conclusion: The patients with chronic discogenic low back pain in this study did not show any improvement at 1-year or 2-year post IDET treatment. A significant proportion of patients underwent further surgery for persisting low back pain. We believe that the efficacy of IDET in the treatment of chronic discogenic low back pain is doubtful

Introduction: The purpose of this study was to evaluate the design of a titanium/polyolefin artificial disc, assess its safety and measure outcome to determine if a RCT is justified. Methods: All subjects entered this pilot study with one or two-level disc disruption at l4/l5 and/or l5/s1 and had disabling low back pain for at least 12 months. The diagnosis was confirmed by discography. Independent assessment included physical examination, VAS for pain, Low-Back Outcome Score (LBOS), Oswestry Disability Index (ODI), SF-36, lateral flexion/extension radiographs and MRI. This was carried out preoperatively, at 6 and 12 weeks, 6 months and at 1 and 2 years. Surgery was performed by an anterior retroperitoneal approach. Results: Twenty-eight cases (14 males; average 41 years) were operated on during 1998–2000. Surgery was performed at L5/S1 in 19, L4/L5 in 5 and both levels in 4. Operating time averaged 130 minutes with 180mls average blood loss. There were no operative complications and average length of stay was 6 days. At 2 years there was 39% average improvement in vas, 15-point average improvement in ODI, 14 point average improvement in LBOS and improvement in 5 of the 8 SF-36 sub-scales. Complications included detection by plain radiographs of early partial displacement of implant in one case and late heterotopic calcification in another. Thin section helical CT, first carried out in early 2001, revealed polyolefin tears in 10 patients, four undergoing revision surgery since 2-year follow-up. CT revealed instances of osteolysis associated with polyolefin failure and hetero-topic bone formation not seen on plain radiographs. Discussion: Although improvements in clinical outcome comparable to that reported with fusion were obtained at two years, detection of elastomer tears by thin section CT in 36% of patients indicated the prosthesis was not suitable for clinical use. This finding was unexpected given the results of prior extensive mechanical testing. 1.

Isthmic spondylolisthesis with pars interarticularis defect is a “ fatigue” fracture. In most cases there is no instability and moderate pain, with no need for treatment. Twenty per cent of the patients have severe back pain, and some also radicular pain, while some young patients have progressive lumbosacral kyphosis and instability with high grade spondylolisthesis. The sacral deformity and kyphosis result from the fracture and could be avoided by healinfg of the defect. Histological studies have shown that the pars defect can be a source of pain. Patients with severe back pain and some with radicular pain or increasing deformity are candidate to surgery. Since many years, the only treatment was fusion with or without instrumentation and with or without correction of the deformity, by anterior or posterior approach. Fusion was mandatory in case of associated disc degeneration, including all the pathological discs into the fusion area. Isthmic repair has been done since many years using several techniques, but only in the absence of olisthesis and disc degeneration. However, it is known that many adult or senile subjects have degenerated discs and no back pain. Thus, what is the rationale to perform fusion in all patients with spondylolisthesis? The problem is to know the source of pain and to treat patients rather than x-rays. This can be achieved by anaesthetic injection of the lytic zone, MRI and discography, which can be helpful to differentiate patients who need fusio from those who do not need it. Initially we used, for isthmic repair, the Morscher hook-screw instrumentation, but in the last ten years we are using DOS instrumentation, which is stiffer. The indications and surgical technique, as well as the results of a comparative study between fusion (91 patients with 40-month follow-up) and repair (95 patients with 30-month followup), wil be presented in terms of duration of surgery, hospital stay, complication rate, number of revisions and return to previous activities. This study shows less postoperative complications and higher rate of return to work or sports for pars repair versus lumbar fusion in a rather similar population. Therefore, isthmic repair seems to be the first surgical option for mild isthmic spondylolisthesis even in the presence of degenerated discs

Recently there has been considerable interest in the role of inflammatory mediator production by herniated degenerate discs. Modic has described MR endplate changes which have an inflammatory appearance and have been linked with discogenic back pain. To date there has been no biomechanical investigation of discs with associated Modic changes. The aim of this study is to determine if degenerate discs with associated Modic changes have higher levels of pro-inflammatory mediator production than those without Modic changes. Intervertebral disc tissue was obtained from 52 patients undergoing spinal surgery for sciatica [40] and discogram proven discogenic low back pain [12]. The tissue was cultured and the medium analysed for interleukin-6, interleukin-8 and prostaglandin E2 using an enzyme linked immunoabsorbetn assay method. Preoperative MR images of the patients were examined by a double blinded radiologist to determine the Modic status of the cultured disc level. Forty percent of patients undergoing surgery for discogenic low back pain had a Modic 1 change compared to only 12.5% of patients undergoing surgery for sciatica [p< .05] There was a statistically significant difference between levels of IL-6, IL-8 and PGE2 production by both the Modic1 [M1] and Modic2 [M2] groups compared to the Modic negative [NEG] group. IL-6:NEGvM1 p< .001, NEG v M2 p< .05, IL-8: NEG v M1 p< .01, NEG v M2 p> .05, PGE2: NEG v M1 p< 01, NEG v M2 p< .05. Modic changes have been associated with positive provocative discography by a number of authors. Pain generation requires the presence of nerves and hyperalgsia inducing mediators. Both IL-8 and PGE2 are known to induce hyperalgesia. The fact that Modic changes are associated with high levels of production of these mediators supports their role as an objective marker of discogenic low back pain

To investigate the efficacy of the navigable intradiscal catheter in the treatment and relief of lumbar discogenic back pain. Twenty-three (23) consecutive patients, at this site, were enrolled into the study by this investigator from normal practice. Inclusion criteria included presentation with predominant low back pain with or without referral leg pain lasting longer than 6 months, diagnosis of DDD or IDD confirmed by plain x-rays, MRI, and positive, low pressure discography, and failure of at least 6 weeks conservative treatment. Outcomes were assessed by clinical exam and administration of the SF-36 Health Survey during the baseline, 3, 6, and 12 month visits. All treatments were performed on an outpatient basis. Following the administration of conscious sedation and local anesthetic, a 17-gauge introducer needle was placed by an extrapedicular approach into the symptomatic disc using fluoroscopic x-ray guidance. A navigable catheter was placed circumferentially to the posterior annular wall. Treatment time was 17 minutes at a maximum tissue temperature of approximately 90°C. Intradiscal antibiotics were employed post procedure and all patients were discharged the day of procedure without complications. Thirty-three (33) lumbar discs were treated. Ten patients had single levels treated; thirteen had double levels treated. Twelve month results show significant improvements in pain as measured by a visual analogue scale (56% decrease, p = 0.035), and the SF-36 sub-scales measuring Bodily Pain (93% decrease, p = 0.011 at 6 months), Physical Functioning (65% increase, p = 0.035), and Role Physical (173% increase, p = 0.020). Overall, 80% of the patients were satisfied with their outcomes (p = 0.004). The intradiscal navigable catheter has proven to be effective in the reduction of pain and an increase in functional abilities for patients who suffer discogenic low back pain due to IDD or DDD

Introduction: Anterior lumbar interbody fusion has become a frequently utilised procedure. The trend has been towards less invasive techniques including laparascopic and mini-open techniques. This report examines the results of one procedure and suggests appropriate tools to decrease the learning curve. Methods: Twenty-two patients with a mean age of 41 (17–78) underwent mini-open ALIF with threaded cortical bone dowels. The same senior surgeon performed all procedures (RFD). Indication for the procedure was discogenic pain verified by concordant discography after a failure of a minimum of six months non-operative treatment. Patients were followed at standard intervals. Complications as well as the evolution of surgical technique were recorded prospectively for all patients. Results: Twenty-one of 22 patients had the successful implantation of two dowels at each level. Intraoperative fluoroscopy and auditory EMG monitoring was used in all cases. Thirty-two levels were fused from L2–S1 (Average =1.39 levels). Average length of stay was 2.96 days (1–14). Follow-up averaged 24.93 months (2–36). Fusion was achieved in 15/16(93%) of the one level cases but only 3/6 (50%) of the two level cases. Posterior reoperation with posterolateral fusion and pedicle screws was performed in 2/3 of these patients. Use of a dedicated pin-based anterior lumbar retractor enabled a 45% reduction in incision length with a 40% decrease in operative time. Complications included: massive bleeding (1), post-operative dysesthetic leg pain (2), postoperative kyphosis (2), lateral graft displacement (1). Discussion and conclusion: ALIF remains a formidable surgical procedure. Precise identification of the midline and use of fluoroscopy assures good placement of the devices. Preoperative osteopenia should be recognised and treated with posterior stabilisation. Posterior stenosis should be a relative contraindication. We have abandoned multilevel standalone procedures given the poor fusion rate. A pin-based retractor allows a smaller incision with less operative time. Attention to myriad technical details remains paramount

Introduction: Biacuplasty is an innovative intervention for the treatment of discogenic pain. It involves inserting electrodes bilaterally into the posterolateral corner of the anulus fibrosus. Radiofrequency current is passed between the electrodes, but each electrode is water-cooled. This prevents coagulation occurring around the surface of the electrode, which allows a three-dimensional lesion to develop between the electrodes. Theoretically this lesion would seal radial and circumferential fissures, and coagulate nerve endings throughout the posterior anulus. Methods: As part of a multi-centre, limited release of biacuplasty, a prospective audit of outcomes was undertaken in 8 patients with chronic low back pain, in whom discography reproduced their pain and post-discography CT demonstrated a radial fissure. They were 6 men and 2 women, aged between 34 and 58 years, who had back pain for longer than 4 years. Four were still working but four were on workers compensation. At the time of writing, all patients had completed clinical assessments before treatment and at one, two, three, and six months after treatment, using a visual analogue scale for pain, and the Oswestry Disability Questionnaire (ODQ) and the SF36 for disability and function. Results: Performed under local anaesthesia, the procedure was painless, and took less than one hour to complete. No complications occurred, and no patient suffered any side-effects. Group pain scores (median; interquartile range) at inception (69; 53–78) improved significantly at one month (35; 11–65) (p = 0.05); deteriorated by three months (41; 14–72) (p = 0.14); but were stable at 6 motns (40; 22–69). Scores for disability (54; 42–67) and physical functioning (33; 13–48) improved (to 50; 29–62 and 50; 20–59, respectively) but did not achieve statistical significance. In categorical terms, however, four patients obtained no benefit, one patient obtained partial, but worthwhile, reduction in pain, but three patients achieved greater than 50% relief of pain at three months, and four did so at 6 months. Reduction in pain was corroborated by a decrease in disability on the ODQ by 11 (5,2) points at three months, and 10 (−4, 15) points at 6 months; and increases in physical functioning on the SF36 by 15 (6,2) points at three months, and 5 (2,2) points at six months. Discussion: These results in Australian patients echo those reported in one of the US arms of the study, in which 8 of 13 patients reduced their pain scores by at least 30 points. Attractive about this new procedure was its ease of execution and painlessness. Although the success rate is modest, this procedure could emerge as an entertainable option for the management of discogenic pain, if its effectiveness can be corroborated in a larger sample and for a longer time

Intra-Discal Electrothermal Therapy (IDET) has been proposed as a treatment for chronic discogenic low back pain. Reports from prospective outcome studies demonstrate statistically significant improvements, but to date there are no published randomized controlled trials assessing efficacy when compared to a placebo group. Ethical Committee approval was obtained prior to the study. Patients with chronic low back pain who failed to improve with conservative therapy were considered for the study. Subjects had one or two level symptomatic disc degeneration as determined by provocative CT/discography. Patients were excluded if there was > 50% loss of disc height or previous back surgery. Fifty-seven patients were randomized with a 2:1 (IDET: Placebo) ratio, 38 to the active IDET arm and 19 to the sham procedure (placebo). In all cases the IDET catheter was positioned under sedation to cover at least 70% of the annular tear defined by the CT/discogram. An independent technician connected the catheter to the generator and either delivered electrothermal energy (active group) or did not (sham group). Both surgeon and patient were blinded to the treatment. Patients followed a standard rehabilitation programme. Low Back outcome score (LBOS), Oswestry Disability Index (ODI), SF-36 questionnaire, Zung Depression Index (ZDI) and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and 6 months. Successful outcome was defined as: no neurological deficit resulting from the procedure, improvement in LBOS of > 7 points, improvements in SF-36 subsets (pain/disability, physical functioning and bodily pain). Two subjects withdrew (both IDET). Baseline demographic data, employment and worker’s compensation status, sitting tolerance, initial LBOS, ODI, SF-36, ZDI and MSPQ were similar for both groups. No neurological deficits occurred as a result of either procedure. No subject in either treatment arm showed improvement of > 7 points in LBOS or specified domains of the SF-36. Mean ODI was 41.4 at baseline and 39.7 at 6 months for the IDET group compared to 40.7 at baseline and 41.5 at six months for the Placebo group. There was no significant change in ZDI or MSPQ for either group. No subject in either treatment arm met criteria for successful outcome. Further analysis showed no significant change in outcome measures in either group at six months. In conclusion, this study demonstrates no significant benefit from IDET over placebo

Introduction: Abnormal pain drawings have been shown in some studies to correlate well with psychological characteristics predicting poor outcome in spinal procedures. Our study evaluated whether pain drawings are a useful predictive tool for outcome following Intradiscal Electrothermal Therapy (IDET). Method: 56 Patients underwent IDET for chronic discogenic lumbar pain as demonstrated by MRI and provocative discography. They were assessed pre and post operatively. Preoperatively patients were assessed by means of a questionnaire. Pain was measured using a visual analogue scale (VAS), a pain drawing was completed and demographic details and employment status were recorded. Post IDET patients were followed up by means of a postal questionnaire. The same details were recorded, in addition to which patients completed a Short Form 36 UK Version 1 and a subjective outcome assessment. Pain drawings were classified as organic or non-organic according to the principle described by Mann et al. Results: 46 (80.7%) patients were successfully followed up. Mean age was 41.2 years (Range 16–76), 27 were female and 19 male. 73.9% of pain drawings were classified as organic and 26.1% as non-organic. The pain diagram was a good predictive tool for outcome following IDET. Patients with “organic” pain drawings showed an improvement in mean pain VAS (Pre-6.7, Post 5.9), high patient satisfaction (Better 67.6%, Same 11.8%, Worse 20.6%), and higher physical component scores of the SF36 (Physical 64.1, Physical Role 45.6, Pain 54.0) compared to the “non-organic” group who demonstrated a deterioration in mean pain VAS (Pre-6.5, Post 8.2), low patient satisfaction (Better 8.3%, Same 58.3%, Worse 33.3%), and lower physical component scores of the SF36 (Physical 38.3, Physical Role 20.8, Pain 26.5). Conclusion: We believe that our study demonstrates that a pre procedure pain diagram can be reliably used as a tool to predict outcome following IDET

Purpose and Background: We have previously reported our investigations of nerve ingrowth into intervertebral discs (IVD) from patients with mechanical low back pain. We have shown that in discs that are painful on discography (pain level discs) nerves actively grow into the deep annulus fibrosus and nucleus pulposus. Nerve ingrowth accompanies blood vessel ingrowth and advances into the nucleus pulposus from the end plate. The morphology and neurochemistry of these nerves indicate them to be nociceptive. The growth of non-myelinated pain fibres in other settings is regulated by the cytokine Nerve Growth Factor (NGF). In this study, we have investigated the production and distribution of NGF, or more particularly its active isoform – NGF-β, and its receptors, in diseased intervertebral discs in order to establish whether this cytokine might be responsible for the observed nerve ingrowth in this situation. Methods: Tissue sections of 21 pain level, 15 non-pain level diseased and 12 normal intervertebral discs, taken at the time of spinal surgery, and from cadavers, were probed by radioactive in situ hybridisation (ISH) for expression of NGF-β, and by immunohistochemistry (IHC) for its high and low affinity receptors (trk-A and p75 respectively). In addition, either serial sections were stained with cell specific markers (CD31 – endothelial cell, PGP9.5 – neurones, GAP43 – actively growing nerves) or sections were doubled stained (two antibodies or both ISH and IHC). Results: We have demonstrated that NGF-β is synthesised by the endothelial cells of blood vessels growing into the IVD from the end plate. The high affinity receptor is expressed by those small nerve fibres that accompany the vessels and in their offshoots in pain level discs that are growing from perivascular nerves into the disc. In addition to their expressing the nerve specific molecule PGP9.5, the trk-A positive cells also express the nerve growth associated protein GAP43. Conclusion: The data indicate that nerve ingrowth into IVD is regulated by NGF-β. We have localised this production to the endothelial cells of ingrowing blood vessels. NGF-β is a potential therapeutic target for the management of back pain

Background Context: One of the main postulated basic principles of total disc replacement (TDR) is the preservation of flexion/extension ability. In neutral position the ideal disc prosthesis should not stay in maximal possible extension which would imply an impingement of the prosthesis. An impingement would cause shear strains on the prosthesis endplates which probably accelerate loosening. Moreover an additional extension ability from the neutral position would indicate no impingement in the facet joints in neutral position and a physiological movement capability. Purpose: The purpose of study was to evaluate a possible impingement of the prosthesis or facet joints after TDR in neutral position. Study design: Prospective evaluation of radiological outcome measures after total disc replacement. Patient sample: The patients (19 female, 10 male) ranged from 29 to 56 years of age (mean: 42.46.5 years). The mean follow up interval averaged 13.2 months (range: 6 – 35 months). The diagnosis of degenerative disc disease was confirmed by MRI (black disc) and discography (positive „Memory pain“). Pain relief after facet joint infiltration was an exlucsion criteria. All patients had a single-level disc replacement (Prodisc II, Spine Solutions) with the same angulation (6). Outcome measures: Evaluation of a possible impingement of the prosthesis and impingement of facet joints in neutral position. Methods: A computer based analysis of pre- and postoperative lateral X-rays in neutral position and dynamic x-rays. The angulation of prosthesis in neutral position and the extension ability in dynamic x-rays were measured. Results: 15 patients showed no extension ability on dynamic x-rays and 10 of these 15 patients had an impingement with maximum extension of the prosthesis on x-rays in neutral position. In the remaining 14 patients the extension ability averaged pre-/postoperatively 2.3/1.3 (p=0.115). In 4 of the 14 patients the pros-thesis showed an impingement in maximum extension and in 10 patients the prosthesis was not in maximum possible extension. Conclusion: Due to the constrained design of the Pro-Disc an impingement is possible and was recognized in nearly 30% of the cases. The imbalance of flexion vs extension bending moments with increase in extension bending moments due to resection of the anterior longitudinal ligament and anterior anulus seems to be a possible explanation. It still remains unclear if an impingement will result in facet joint protection or will trigger a loosening of the implant. A prosthesis design which preserves the anterior longitudinal ligament would be probably a possible solution

Introduction: Intra-Discal Electrothermal Therapy (IDET) has been proposed as a treatment for chronic discogenic low back pain. Reports from prospective outcome studies demonstrate statistically significant improvements, but there are no published randomized controlled trials assessing efficacy against a placebo group. Methods: Ethical committee approval was obtained prior to the study. Patients with chronic low back pain who failed conservative treatment were considered for the study. Inclusion criteria included one or two level symptomatic internal disc disruption as determined by provocative CT/discography. Patients were excluded if there was > 50% loss of disc height or had had previous back surgery. Fifty-seven patients were randomized with a 2:1 (IDET: Placebo) ratio, 38 to the active IDET arm and 19 to the sham (placebo). The IDET catheter was positioned under sedation to cover at least 75% of the annular tear as defined by the CT/discogram. An independent technician connected the catheter to the generator and either delivered electrothermal energy (active group) or did not (sham group). Surgeon, patient and independent outcome assessor were all blinded. All patients followed a standard rehabilitation programme. Outcome Measures: Low Back Outcome Score (LBOS), Oswestry Disability Index (ODI), SF-36 questionnaire, Zung Depression Index (ZDI) and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and 6 months. Successful outcome was defined as: No neurological deficit resulting from the procedure, improvement > 7 points in LBOS, improvements > 7 points in SF-36 subsets (pain / disability, physical functioning and bodily pain). Results: Two subjects withdrew from the study (both IDET). Baseline demographic data, employment and worker’s compensation status, sitting tolerance, initial LBOS, ODI, SF-36, ZDI and MSPQ were similar for both groups. No neurological deficits occurred as a result of either procedure. No subject in either treatment arm showed improvement of > 7 points in LBOS or the specified domains of the SF-36. Mean ODI was 41.4 at baseline and 39.7 at 6 months for the IDET group compared to 40.7 at baseline and 41.5 at six months for the Placebo group. There was no significant change in ZDI or MSPQ scores for either group. Discussion: No subject in either treatment arm met criteria for successful outcome. There was no significant change in outcome measures in either group at six months. This study demonstrates no significant benefit from IDET over placebo

Introduction: Intradiscal electrothermal therapy (IDET) is a controversial, new treatment for low back pain, whose efficacy has not been tested in randomized trials. The present study was undertaken to compare the efficacy of IDET with that of a placebo treatment. Methods: Patients were recruited by referral and by advertising in the media. Of 4,530 individuals who enquired, 1,360 were prepared to submit to randomization. Of these, 260 were found potentially eligible after clinical examination, and 64 became eligible after discography. All had discogenic low back pain lasting longer than 6 months, with no comorbidity. Thirty-seven were allocated to IDET, and 27 to sham therapy. Both groups were satisfactorily matched for demographic and clinical features. IDET was performed using a standard protocol, in which the posterior annulus of the painful disc was heated to 90°C. Sham therapy consisted of introducing a needle onto the disc and exposing the patient to the same visual and auditory environment as for a real procedure. Follow-up at 6 months was achieved in over 85% of patients. Pain and disability were assessed using a visual analog scale for pain, the SF-36, the Oswestry disability scale, and the Back Depression Inventory. Results: Patients in both groups exhibited improvements, but improvements in pain, disability, and depression, were significantly greater in the group treated with IDET. Pain scores improved by 24 points in the IDET group compared with 11 in the sham group. Oswestry scores improved by 11 in the IDET group, but only by 4 in the sham group. More patients deteriorated when subjected to sham treatment, whereas eight patients (25%) achieved greater than 75% relief of pain following IDET. Only one patient did so after sham treatment. The number needed to treat, to achieve 75% relief of pain, was 5. No patient suffered any adverse effects. Discussion: IDET fails to provide relief in some 50% of patients. Consequently, its efficacy is difficult to demonstrate statistically. Nevertheless, IDET provides satisfying relief in a substantial proportion of patients. Non-specific factors account for a large proportion of the apparent efficacy of IDET, but its efficacy cannot be attributed wholly to a placebo effect. The efficacy of IDET may be related critically to patient selection and the technique used. Improvements in either of these areas may improve the effect-size of IDET. Meanwhile, IDET is a low risk procedure that constitutes a legitimate option for patients with discogenic low back pain whose only alternative is fusion

INTRODUCTION: Intradiscal electrothermal therapy (IDET) is a controversial, new treatment for low back pain, whose efficacy has not been tested in randomised trials. The present study was undertaken to compare the efficacy of IDET with that of a placebo treatment. METHODS: Patients were recruited by referral and by advertising in the media. Of 4,530 individuals who enquired, 1,360 were prepared to submit to randomisation. Of these, 260 were found potentially eligible after clinical examination, and 64 became eligible after discography. All had discogenic low back pain lasting longer than six months, with no co-morbidity. Thirty-seven were allocated to IDET, and 27 to sham therapy. Both groups were satisfactorily matched for demographic and clinical features. IDET was performed using a standard protocol, in which the posterior annulus of the painful disc was heated to 90°C. Sham therapy consisted of introducing a needle on to the disc and exposing the patient to the same visual and auditory environment as for a real procedure. Follow-up at six months was achieved in over 85% of patients. Pain and disability were assessed using a visual analog scale for pain, the SF-36, the Oswestry disability scale, and the Back Depression Inventory. RESULTS: Patients in both groups exhibited improvements, but improvements in pain, disability, and depression, were significantly greater in the group treated with IDET. Pain scores improved by 24 points in the IDET group compared with 11 in the sham group. Oswestry scores improved by 11 in the IDET group, but only by four in the sham group. More patients deteriorated when subjected to sham treatment, whereas eight patients (25%) achieved greater than 75% relief of pain following IDET. Only one patient did so after sham treatment. The number needed to treat, to achieve 75% relief of pain, was five. No patient suffered any adverse effects. DISCUSSION: IDET fails to provide relief in some 50% of patients. Consequently, its efficacy is difficult to demonstrate statistically. Nevertheless, IDET provides satisfying relief in a substantial proportion of patients. Non-specific factors account for a large proportion of the apparent efficacy of IDET, but its efficacy cannot be attributed wholly to a placebo effect. The efficacy of IDET may be related critically to patient selection and the technique used. Improvements in either of these areas may improve the effect-size of IDET. Meanwhile, IDET is a low risk procedure that constitutes a legitimate option for patients with discogenic low back pain whose only alternative is fusion

Introduction: Surgical management of discogenic low back pain has in the past been limited to spinal fusion. Recently disc arthroplasty has become available. The rationale for disc arthroplasty is that it may avoid the long term consequences of adjacent segment degeneration. Avoidance of long term consequences is of no value unless the short term outcome is at least equivalent between fusion and arthroplasty. Methods: A series of patients with chronic low back pain with concordant lumbar discography and a negative control discogram were surgically treated. Prospective data was collected preoperatively and at regular intervals during the post-operative period for a historical series of combined anterior and posterior lumbar fusion (n =24), a series of SB Charité (DePuy Spine) disc replacements (n =23), and recently, a series of Maverick (Medtronic Sofamor Danek) artificial disc replacements (n =9). Self assessed outcome measures of visual analog pain score (VAS), Low Back Outcome Score (LBOS) and SF12 general health data was obtained at intervals after the surgery. This paper presents the results of the consecutive series that have a minimum of 3 months follow-up. Results: The data for the two groups of arthroplasty was combined and compared to the fusion group. The mean age for the fusion group was 37.6 years and the mean age for the arthroplasty group was 38.6 years. There were 5 compensation cases (20.8 %) in the fusion group and 5 cases (15.6 %) in the arthroplasty group. Both groups had 69% male patients. The mean VAS dropped from 7.5 to 3.7 (p< 0.001) in the arthroplasty group and from 7.3 to 3.5 (p< 0.001) in the fusion group. The mean LBOS improved from 22.0 to 36.5 (p< 0.001) in the arthroplasty group and from 19.6 to 37.1 (p< 0.001) in the fusion group. There was no apparent difference between the clinical improvement in VAS and LBOS (p=0.91 and p=0.45 respectively) for each group. Analysis of the power of the comparison showed an 86% power for comparison of VAS improvement using a clinically important difference (delta) of 1 VAS point and there was 98% power for the LBOS improvement comparison using a clinically important difference (delta) of 10 LBOS points. Complications appeared higher in the arthroplasty group with foraminal encroachment requiring revision in 3 cases and one case of polyethylene failure in the Charité group at 3 years. This case occurred with an 8mm polyethylene insert (since removed from inventory by the manufacturer). Discussion: Disc arthroplasty in the lumbar spine appears to offer similar short term results to that of fusion for chronic low back pain. The surgical complication rate may be higher in the early learning curve of the procedure

Introduction Intra-Discal Electrothermal Therapy (IDET) has been proposed as a treatment for chronic discogenic low back pain. Reports from prospective outcome studies demonstrate statistically significant improvements, but to date there are no published randomized controlled trials assessing efficacy versus a placebo group. Methods Ethical committee approval was obtained prior to the study. Patients with chronic low back pain who failed to improve with conservative therapy were considered. Inclusion criteria included the presence of one or two level symptomatic disc degeneration with posterior or postero-lateral annular tears as determined by provocative CT/discography. Patients were excluded if there was > 50% loss of disc height or previous back surgery. Fifty-seven patients were randomized with a 2:1 (IDET: Placebo) ratio, 38 to the active IDET arm and 19 to the sham procedure (placebo). In all cases the IDET catheter was positioned under sedation to cover at least 70% of the annular tear defined by the CT/discogram. An independent technician connected the catheter to the generator and either delivered electrothermal energy (active group) or did not (sham group). Both surgeon and patients were blinded to the treatment. Patients followed a standard post-procedural rehabilitation programme. Low Back Outcome Score (LBOS), Oswestry Disability Index (ODI), SF-36 questionnaire, Zung Depression Index (ZDI) and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and six months. Successful outcome was defined as: no neurological deficit resulting from the procedure, improvement in LBOS of > 7 points, improvements in SF-36 subsets (pain/disability, physical functioning and bodily pain). Two subjects withdrew from the study (both IDET). Baseline demographic data, employment and workers’ compensation status, sitting tolerance, initial LBOS, ODI, SF-36, ZDI and MSPQ were similar for both groups. Results No neurological deficits occurred as a result of either procedure. No subject in either treatment arm showed improvement of > 7 points in LBOS or specified domains of the SF-36. Mean ODI was 41.4 at baseline and 39.7 at six months for the IDET group compared to 40.7 at baseline and 41.5 at six months for the placebo group. There was no significant change in ZDI or MSPQ scores for either group. No subject in either treatment arm met criteria for successful outcome. Further analysis showed no significant change in outcome measures in either group at six months. Conclusions This study demonstrates no significant benefit from IDET over placebo

Introduction: Infection can occur after any spinal procedure that involves entry into the disc and although it is not common, the potential consequences are serious. Treatment usually requires identification of the bacteria followed by a course of antibiotics. This treatment remains controversial since it is not clear whether antibiotics actually penetrate the disc and if so, whether they are effective, or even if the outcome would be the same without antibiotics. For an antibiotic to be effective against the infecting organism it must diffuse through the disc matrix. Blood vessels that surround the disc facilitate the diffusion process, but with age this vascularity decreases and may impede diffusion. The aims of the pilot study were to assess the effectiveness of antibiotic in treating infection in both normal and degenerate sheep discs and to measure the concentration of antibiotic in non-operated discs at varying ages. Methods: In each of six Merino wethers aged 12 weeks (n=3) and 24 months (n=3), two lumbar discs were “degenerated” by incising the posterolateral annulus with a scalpel blade. After four weeks all animals had discography with radiographic contrast that contained Staphylococcus aureus at the incised levels and at two non-incised levels. Seven days after infection four animals began IV antibiotic treatment with cephazolin sodium (David Bull Laboratories, Australia) for 21 days at a dose of 50mg/kg/day. The antibiotic was chosen for effectiveness against S. aureus. One control animal from each age group did not receive any antibiotics, to follow the natural progression of infection. Lateral radiographs of the lumbar spine were taken at two, six and 12 weeks. At 12 weeks all sheep were given a single intravenous dose of cephazolin sodium as either a 1, 2 or 3g dose. The sheep were then killed after 30 minutes. The spines were removed and prepared for light microscopy to assess pathology of the discs and for biochemical analysis of antibiotic concentration. Success of treatment was judged using histologic and radiographic features. Results: Discitis was evident radilogically as early as two weeks after inoculation in all animals. Histology at 12 weeks confirmed discitis in all discs regardless of treatment. Biochemistry results confirmed that antibiotic diffused throughout the disc but was more concentrated in the annulus than the nucleus. At all doses disc concentration of antibiotic was higher in lambs than sheep. Discussion: Treatment with cephazolin sodium at a dose of 50mg/kg/day for 21 days administered from seven days after inoculation, did not prevent discitis. This does not appear to be due to inability of antibiotic diffusion into the disc

Introduction: Recent evidence from the Swedish Lumbar Spine Group has confirmed the anecdotal opinions of many spinal surgeons that fusion for persistent back pain can be a very effective treatment. However, it is clear that many more variables operate in determining clinical success than just radiological evidence of solid fusion. The very careful selection of patients for low back surgery is, in the opinion of the authors, the most important predictor of success. This paper addresses this issue and presents data to show why clinical failure can coexist with radiological success. Methods: Between October 1997 and January 2001, 3600 spinal fusion using Diapason pedicle screw instrumentation and Brantigan anterior interbody fusion cages was performed on 25 patients. During this period 5,850 new outpatients with back pain were assessed in the low back clinic. Patients were selected by the following criteria: Low back pain of two years or more duration; Pain resistant to all non-operative and minimally invasive treatments; Normal psychosocial profile; Normal body mass index; Non-Smokers; Single or two level disease on MRI proven to be painful by provocative discography; No current insurance or workers-compensation claims. Postal follow-up was at a minimum of 2 years post-surgery (mean 47 months) using the Low Back Outcome Score (LBOS) and x-rays taken at the two-year clinic follow-up were independently assessed to determine fusion. Results: 24 patients returned the questionnaire (96%). Only 20 (83%) patients had ‘good’ or ‘excellent’ results, as defined by the LBOS. However, 92% of patients stated that they would opt to have a circumferential fusion again, if guaranteed the same post-operative result. The same number of patients stated they would recommend the treatment to friend or family member. Analysis of the post-operative radiographs revealed that spinal fusion (as defined by the Brantigan and Steffee criteria) was present in all 25 cases. Conclusions: Our opinion that patient selection is the most important predictor of satisfactory outcome in spinal surgery is demonstrated in this study by the mismatch between the clinical and radiological results. We have identified the causes of clinical failure in this group of patients as: Multiple sites of musculoskeletal pain confounding the LBOS; Neuropathic leg pain that cannot respond to surgical treatment; More than two previous spinal operations; Excessive pre-operative disability and functional loss that confounds the LBOS; Poor psychosocial profile. Stringent application of rigid selection criteria might improve outcomes in lumbar spinal fusion so that clinical and radiological results correlate more closely. However, even with adherence to such rigid criteria, the outcome tool (LBOS) may be confounded and a more holistic assessment of outcome, including a more sensitive subjective assessment of satisfaction, might be a better measure

Introduction: Intra-Discal Electrothermal Therapy (IDET) has been proposed as a treatment for chronic discogenic low back pain. Reports from prospective outcome studies demonstrate statistically significant improvements, but to date there are no published randomized controlled trials assessing efficacy versus a placebo group. Methods: Ethical committee approval was obtained prior to the study. Patients with chronic low back pain who failed to improve with conservative therapy were considered for the study. Inclusion criteria included the presence of one or two level symptomatic disc degeneration with posterior or posterolateral annular tears as determined by provocative CT/discography. Patients were excluded if there was > 50% loss of disc height or previous back surgery. Fifty-seven patients were randomized with a 2:1 (IDET: Placebo) ratio, 38 to the active IDET arm and 19 to the sham procedure (placebo). In all cases the IDET catheter was positioned under sedation to cover at least 70% of the annular tear defined by the CT/ discogram. An independent technician connected the catheter to the generator and either delivered electrothermal energy (active group) or did not (sham group). Both surgeon and patient were blinded to the treatment. Patients followed a standard post-procedural rehabilitation programme. Outcome Measures: Low Back Outcome Score (LBOS), Oswestry Disability Index (ODI), SF-36 questionnaire, Zung Depression Index (ZDI) and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and 6 months. Successful outcome was defined as: No neurological deficit resulting from the procedure, improvement in LBOS of > 7 points, improvements in SF-36 subsets (pain / disability, physical functioning and bodily pain). Results: Two subjects withdrew from the study (both IDET). Baseline demographic data, employment and worker’s compensation status, sitting tolerance, initial LBOS, ODI, SF-36, ZDI and MSPQ were similar for both groups. No neurological deficits occurred as a result of either procedure. No subject in either treatment arm showed improvement of > 7 points in LBOS or specified domains of the SF-36. Mean ODI was 41.4 at baseline and 39.7 at 6 months for the IDET group compared to 40.7 at baseline and 41.5 at six months for the Placebo group. There was no significant change in ZDI or MSPQ scores for either group. Discussion: No subject in either treatment arm met criteria for successful outcome. Further analysis showed no significant change in outcome measures in either group at six months. This study demonstrates no significant benefit from IDET over placebo

INTRODUCTION: Intra-Discal Electrothermal Therapy (IDET) has been proposed as a treatment for chronic discogenic low back pain. Reports from prospective outcome studies demonstrate statistically significant improvements, but to date there are no published randomised controlled trials assessing efficacy versus a placebo group. METHODS: Ethical committee approval was obtained prior to the study. Patients with chronic low back pain who failed to improve with conservative therapy were considered for the study. Inclusion criteria included the presence of one or two level symptomatic disc degeneration with posterior or posterolateral annular tears as determined by provocative CT/discography. Patients were excluded if there was > 50% loss of disc height or previous back surgery. Fifty-seven patients were randomised with a 2:1 (IDET: Placebo) ratio, 38 to the active IDET arm and 19 to the sham procedure (placebo). In all cases the IDET catheter was positioned under sedation to cover at least 70% of the annular tear defined by the CT/ discogram. An independent technician connected the catheter to the generator and either delivered electrothermal energy (active group) or did not (sham group). Both surgeon and patient were blinded to the treatment. Patients followed a standard post-procedural rehabilitation programme. OUTCOME MEASURES: Low Back Outcome Score (LBOS), Oswestry Disability Index (ODI), SF-36 questionnaire, Zung Depression Index (ZDI) and Modified Somatic Perceptions Questionnaire (MSPQ) were measured at baseline and six months. Successful outcome was defined as: No neurological deficit resulting from the procedure, improvement in LBOS of > 7 points, improvements in SF-36 subsets (pain/disability, physical functioning and bodily pain). RESULTS: Two subjects withdrew from the study (both IDET). Baseline demographic data, employment and worker’s compensation status, sitting tolerance, initial LBOS, ODI, SF-36, ZDI and MSPQ were similar for both groups. No neurological deficits occurred as a result of either procedure. No subject in either treatment arm showed improvement of > 7 points in LBOS or specified domains of the SF-36. Mean ODI was 41.4 at baseline and 39.7 at six months for the IDET group compared to 40.7 at baseline and 41.5 at six months for the Placebo group. There was no significant change in ZDI or MSPQ scores for either group. DISCUSSION: No subject in either treatment arm met criteria for successful outcome. Further analysis showed no significant change in outcome measures in either group at six months. This study demonstrates no significant benefit from IDET over placebo

INTRODUCTION: Infection can occur after any spinal procedure that involves entry into the disc and although it is not common, the potential consequences are serious. Treatment usually requires identification of the bacteria followed by a course of antibiotics. This treatment remains controversial since it is not clear whether antibiotics actually penetrate the disc and if so, whether they are effective, or even if the outcome would be the same without antibiotics. For an antibiotic to be effective against the infecting organism it must diffuse through the disc matrix. Blood vessels that surround the disc facilitate the diffusion process, but with age this vascularity decreases and may impede diffusion. The aims of the pilot study were to assess the effectiveness of antibiotic in treating infection in both normal and degenerate sheep discs and to measure the concentration of antibiotic in non-operated discs at varying ages. METHODS: In each of six Merino wethers aged 12 weeks (n=3) and 24 months (n=3), two lumbar discs were “degenerated” by incising the posterolateral annulus with a scalpel blade. After four weeks all animals had discography with radiographic contrast that contained Staphylococcus aureus at the incised levels and at two non-incised levels. Seven days after infection four animals began IV antibiotic treatment with cephazolin sodium (David Bull Laboratories, Australia) for 21 days at a dose of 50 mg/kg/day. The antibiotic was chosen for effectiveness against S. aureus. One control animal from each age group did not receive any antibiotics, to follow the natural progression of infection. Lateral radiographs of the lumbar spine were taken at two, six and 12 weeks. At 12 weeks all sheep were given a single intravenous dose of cephazolin sodium as either a 1, 2 or 3 g dose. The sheep were then killed after 30 minutes. The spines were removed and prepared for light microscopy to assess pathology of the discs and for biochemical analysis of antibiotic concentration. Success of treatment was judged using histologic and radiographic features. RESULTS: Discitis was evident radiologically as early as two weeks after inoculation in all animals. Histology at 12 weeks confirmed discitis in all discs regardless of treatment. Biochemistry results confirmed that antibiotic diffused throughout the disc but was more concentrated in the annulus than the nucleus. At all doses disc concentration of antibiotic was higher in lambs than sheep. DISCUSSION: Treatment with cephazolin sodium at a dose of 50 mg/kg/day for 21 days administered from seven days after inoculation, did not prevent discitis. This does not appear to be due to inability of antibiotic diffusion into the disc

INTRODUCTION: Recent evidence from the Swedish Lumbar Spine Group has confirmed the anecdotal opinions of many spinal surgeons that fusion for persistent back pain can be a very effective treatment. However, it is clear that many more variables operate in determining clinical success than just radiological evidence of solid fusion. The very careful selection of patients for low back surgery is, in the opinion of the authors, the most important predictor of success. This paper addresses this issue and presents data to show why clinical failure can coexist with radiological success. METHODS: Between October 1997 and January 2001, 360° spinal fusion using Diapason pedicle screw instrumentation and Brantigan anterior interbody fusion cages was performed on 25 patients. During this period 5,850 new outpatients with back pain were assessed in the low back clinic. Patients were selected by the following criteria: Low back pain of two years or more duration; Pain resistant to all non-operative and minimally invasive treatments; Normal psycho-social profile; Normal body mass index; Non-Smokers; Single or two level disease on MRI proven to be painful by provocative discography; No current insurance or workers-compensation claims. Postal follow-up was at a minimum of two years post-surgery (mean 47 months) using the Low Back Outcome Score (LBOS) and X-rays taken at the two-year clinic follow-up were independently assessed to determine fusion. RESULTS: 24 patients returned the questionnaire (96%). Only 20 (83%) patients had ‘good’ or ‘excellent’ results, as defined by the LBOS. However, 92% of patients stated that they would opt to have a circumferential fusion again, if guaranteed the same post-operative result. The same number of patients stated they would recommend the treatment to friend or family member. Analysis of the post-operative radiographs revealed that spinal fusion (as defined by the Brantigan and Steffee criteria) was present in all 25 cases. CONCLUSIONS: Our opinion that patient selection is the most important predictor of satisfactory outcome in spinal surgery is demonstrated in this study by the mismatch between the clinical and radiological results. We have identified the causes of clinical failure in this group of patients as: Multiple sites of musculo-skeletal pain confounding the LBOS; Neuropathic leg pain that cannot respond to surgical treatment; More than two previous spinal operations; Excessive pre-operative disability and functional loss that confounds the LBOS; Poor psychosocial profile. Stringent application of rigid selection criteria might improve outcomes in lumbar spinal fusion so that clinical and radiological results correlate more closely. However, even with adherence to such rigid criteria, the outcome tool (LBOS) may be confounded and a more holistic assessment of outcome, including a more sensitive subjective assessment of satisfaction, might be a better measure

Introduction The Dynesys® stabilisation system (Zimmer Spine) uses transpedicular screws linked by a cord and spacers; the advantage claimed is that it allows some motion, in all directions, in the operated levels. In vitro laboratory biomechanical studies show that the movement permitted is similar to rigid fixation systems. This study measures the changes in the lumbar spine in different postures, pre- and after insertion of the device. Methods In our study 25 patients with dominant low back pain, with or without leg pain, were treated with Dynesys system, 14 females and 11 males with mean age 43.5 yrs. Discography was done to evaluate the symptomatic painful level. All patients had a positional magnetic resonance imaging (pMRI) scans preoperatively and nine months post-operatively in standing; sitting flexion and extension, and left and right bending postures. The patients were initially divided into two groups. The first (Group A) with 14 patients in which only Dynesys was used (disc height 40–90%) and the second (group B) with 11 patients in which Dynesys was used with fusion (disc height < 40 %). Results The operated levels were 51, 13 of which were fused. The results of the pMRI measurements showed that the mean range of movement of the lumbosacral angle reduced by 10.3° from pre-op of 39.2° to postop. of 28.9° (p= 0.016) in group A while in group B it reduced by 13.7° from 36.2° preop. to 22.5° postoperatively (p= 0.02). The range of movement of the end plate angle at the instrumented segments in group A reduced from 5.6° preoperatively to 2.6° with a difference of 3.0° (p=0.016) while in group B it reduced from 6.7° to 2.5° postoperatively with a difference of 4.2°(p=0.008). The range of movement of the end plate angle at adjacent level in group A changed from 8.8° preop. to 7.2° with a reduction of 1.6° (p=0.427) while in group B it increased from 6.9° to 8.6°, difference of 1.7° (p=0.149). The mean anterior disc height in group A reduced by 1.2mm (p< 0.005) from 10.1mm to 8.9mm postoperatively, and the posterior one was increased from 6.5mm to 8.9mm with a difference of 0.6mm (p= 0.013). In group B the anterior disc height was reduced by 1.1mm (pre-op 10.4mm to post-op 9.3mm; p=0.049) and the posterior one by 0.16mm (pre-op 6.98mm to post-op 6.82mm; p=0.714). Discussion This study shows that in the Dynesys stabilising system allows a small range of movement at the instrumented levels, with no significant increased mobility in the adjacent levels. Also the device acted to compress the anterior annulus more than to distract the posterior annulus

Introduction: Although prophylactic antibiotic administration is common in spinal surgery, the choice of drug, dose, and timing of administration often varies. Little is known about the activity of antibiotics in the spine and indeed if they are distributed throughout the disc and if the time intervals are optimal. Because infections that produce iatrogenic discitis generally arise within the disc, the antibiotic concentration of the disc is more relevant than serum concentrations. The aims of the study were to determine if a 2g dose of cephazolin was effective at preventing discitis over a four-hour period in immature ovine discs that were both non-degenerate and degenerate; and also to determine the concentration of cephazolin in serum and disc tissue. Methods: In 10 Merino wethers aged 12 weeks, three lumbar discs were “degenerated” by incising the posterolateral annulus with a scalpel blade and using ronguers, removing the bulk of the nucleus pulposus. After 12 weeks nine animals were anaesthetised and given a 2g dose of cephazolin (David Bull Laboratories, Australia) at predetermined time intervals over a four-hour period. The antibiotic was chosen for effectiveness against Staphylococcus aureus a common discitis-causing organism. One sheep (control) did not receive any antibiotics to follow the natural progression of infection. All animals had discography with radiographic contrast that contained S. aureus at two incised levels and at two non-incised levels. Lateral radiographs of the lumbar spine were taken at two, six and 12 weeks to monitor the bony changes. At 12 weeks all sheep were given a 2g intravenous dose of cephazolin at time intervals before being killed. The spines were removed and prepared for light microscopy to assess pathology of the discs and for biochemical analysis of antibiotic concentration. Success of treatment was judged using histologic and radiographic features. Results: The control sheep that did not receive any antibiotics developed discitis at four levels. Histology at 12 weeks confirmed discitis in 10/36 “prophylactic discs”. Of these “prophylactic discs” 7/10 had previously been “degenerated”. Discitis only developed in immature discs that were administered cephazolin two hours prior to inoculation. When antibiotic was administered after inoculation discitis was prevented. Biochemistry results confirmed that antibiotic diffused throughout the disc but was concentrated in the annulus more than the nucleus. Antibiotic levels in the disc peaked at 15 minutes (annulus mean concentration 15.5 mg/L, nucleus mean concentration 3.2 mg/L). Serum levels at 15 minutes were up to 50 times greater at this time (serum mean concentration 178 mg/L). Discussion: The discs that were “degenerate” had a higher incidence of discitis compared to “non-degenerate” discs. However the concentration of antibiotic in degenerate discs was not significantly different than in non-degenerate discs. A 2 gram dose of cephazolin is reasonably effective (approx 70% success rate) at preventing discitis over a four-hour period

This is a preliminary retrospective report on a novel technique for achieving fusion at the lumbo-sacral disc. Current methods of complete discectomy and instrumented fusion involve either a posterior approach and the insertion of cages or an anterior approach. Both methods involve quite extensive dissections with potential stabilising muscle stripping. They also require significant post operative analgesia, inpatient stay and post operative recovery. There are attendant risks of nerve injury, blood loss and thrombosis. A novel method of approach from the sacrum via a ‘safe zone’, described by Yuan et al., is presented. The technique along with the anatomical considerations is described. The operation basically consists of a posterior sacrococcygeal incision and an x-ray guided approach to the anterior surface of the S1/S2 junction with blunt obturators. The L5/S1 disc is then accessed by drilling through the sacrum. The disc is then removed from within with shaped tools leaving the bulk of the annulus. The void created is filled with bone graft and the L5 vertebra fixed to the sacrum via a bolt. The initial results of the first 20 patients are presented. 21 patients have been operated upon but one has been lost to follow up due to a psychological disorder. That patients details have been excluded. The patients underwent surgery between 4/7/06 and 8/10/07. All operative procedures were completed without complication, the operative time improving from 60 minutes to a ‘standard’ 45 minutes. There were no post operative complications. Two patients underwent additional procedures. One was an L4/5 Wallis ligament the other an inter-transverse non instrumented fusion. Several patients required a further pain control procedure, 3 caudal epidurals, 2 facet blocks and 2 coccyx injections. One patient required an L4/5 PLIF 12 months after the first procedure and two patients required posterior stabilisation at the same level. One after 4 months the other at 18 months. The indications for surgery are the same as for a standard fusion procedure. In this group there were 12 degenerative discs with mechanical LBP, 3 spondylolistheses, 2 previous failed posterior fusions and 3 post discectomy patients. Discography was used for confirmation of the pain source in 15 cases. The duration of symptoms ranged between 2–15 years with a mean of 6.25. There were 12 male and 8 female patients. The age ranged between 34–70 with a mean of 47. The female mean being 48 and the male 46. The Oswestry disability index showed a mean of 47 pre-operation and 23 post-operation. 13 out of 20 have been discharged with symptoms resolved or easily bearable. The hospital stay varied between 1 night and 4 nights with a mean of 3.3. This novel approach to the lumbar spine gives rapid and safe access to the lumbar disc space despite the unusual approach for spinal surgeons. Once the initial incision is made the procedure is carried out under x-ray control using techniques which are very familiar to Orthopaedic surgeons. The lack of intra-operative problems and post-operative complications testify to a safe procedure. The question mark remains on the rate of fusion. Two patients and potentially a third required a secondary posterior instrumented fusion. One was due to demonstrable loosening of the bolt and the other two continued pain possibly due to inadequate stabilisation. In my view, despite the European teaching, posterior instrumentation is desirable. This can be achieved via a percutaneous technique

Introduction Current evidence suggests that, in the short and medium term, total disc arthroplasty (TDA) is at least as good as fusion for the management of discogenic low back pain. The optimum kinematic design of TDA, however, at this stage has not been identified. This paper compares the clinical outcomes of two TDA prostheses with different kinematic properties. Methods A randomised comparative clinical study with prospective data collection was performed. Two groups of patients with low back pain who were treated surgically with TDA were compared. All patients had primary symptoms of low back pain without significant facet degeneration. All patients had MRI evidence of disc degeneration and positive discography at the target level. The two surgical groups were treated consecutively by the one surgeon. The first chronological group consisted of 23 cases of SB Charité (CHR) prostheses (DePuy Spine) and the second group consisted of 18 cases of Maverick (MAV) disc replacements (Medtronic Sofamor Danek). The CHR group consisted of 16 males and 7 females with an average age of 37.1 years. The MAV group consisted of 10 males and 8 females with an average age of 41.3 years. 17 (74%) of the CHR group were single level cases. 6 (24%) cases were performed at the same time as an adjacent level anterior fusion. There were no two level prostheses performed. One case in the CHR group was lost to follow-up. 10 (55%) of the MAV group were single level cases. 7 (38%) of the MAV group were double level prosthesis cases. There was 1 case performed adjacent to a fusion in this group. Patients were assessed by visual analogue pain scores (VAS), Low-Back outcome score (LBOS), and SF12 health outcomes that were collected preoperatively and at 6 months. Results There was a mean improvement of 3.4 VAS points with the CHR group compared to a mean improvement of 5.1 points with the MAV group (p=0.039). There was a mean percentage improvement in VAS scores of 42.1% with the CHR group compared to a 70.1% improvement in the MAV group (p=0.003). The mean LBOS scores improved by 12.3 points in the CHR group, compared to an improvement of 25.6 points in the MAV group (p=0.016). Percentage improvement in LBOS score was 67.8% for the CHR group compared to 210% for the MAV group (p=0.006). The mean improvement in the PCS score of the SF12 measure was 7.3 for the CHR group compared to 15.6 for the MAV group (p=0.055). The percentage improvement in PCS scores was 23.1% for the CHR group compared to 56.0% for the MAV group (p=0.047). There was no significant difference in the improvement in MCS score of the SF12 measure (6.3 compared to 8.1 p=0.7). Discussion On all outcome measures of pain and physical disability the MAV cases improved by a statistically greater amount than the CHR cases. This difference appears to be clinically important. There are a number of possible reasons for this difference, including the fact that the cases were not performed concurrently (learning curve affect) and that there were a number of fusions performed simultaneously in the CHR group. However one possible explanation is the difference in the kinematic behaviour of the two prostheses

The National Institute for Health and Care Excellence has issued guidelines that state fusion for non-specific low back pain should only be performed as part of a randomised controlled trial, and that lumbar disc replacement should not be performed. Thus, spinal fusion and disc replacement will no longer be routine forms of treatment for patients with low back pain. This annotation considers the evidence upon which these guidelines are based.

Cite this article: Bone Joint J 2017;99-B:1003–1005.