Discogenic Low Back Research Articles

‘Progressive-Onset’ versus Injury-Associated Discogenic Low Back Pain: Features of Disc Internal Derangement in Patients Studied with Provocation Lumbar Discography

Chronic low back pain (LBP) can be 'progressive onset' or injury-related. This study compares the patient-reported cause of chronic LBP to features of disc internal derangement at painful concordant discs evaluated by provocation lumbar discography. Concordant LBP was identified in 114 patients with chronic LBP studied by provocation discography. LBP cause, discogram pain response and discogram/post-discogram CT features of internal derangement were retrospectively reviewed. 'Progressive-onset' LBP was reported in 32 (28%) patients, injury-related LBP in 75 (66%) with LBP equated to non-specific causes in seven. Injury-related LBP was more commonly identified in men (52 of 63 [83%]) with women reporting near-equal frequency of 'progressive-onset' (23 of 44 [52%]) and injury-related (21 of 44 [48%]) LBP (p=0.002). In 172 concordant painful discs, near-equal frequency of severely degenerative (Dallas grade-3: 82 of 172 [47.3%]) and full-thickness radial fissure discs (Dallas grade-3: 90 of 172 [52.7%]) were identified. Women with 'progressive-onset' LBP demonstrated more frequent severely degenerative discs (24 of 37 [65%]); women with injury-related LBP demonstrated more frequent radial-defect discs (21 of 31 [68%]; p=0.01). In men with injury-related LBP, severe degeneration-only (44 of 89 [49%]) and radial defect discs (45 of 89 [51%] were seen with equal frequency. In men with 'progressive-onset' LBP, radial defects are more common (11 of 15 [73%]). 'Progressive-onset' and injury-related chronic LBP subgroups are definable. Gender-related differences in incidence and internal derangement features at concordant discs are identified at discogram/post-discogram CT. These differences may have implications related to LBP origin/treatment-response.

Prospective Clinical Study on Natural History of Discogenic Low Back Pain at 4 Years of Follow-up

Background: To accurately assess the effect of any therapy for treating discogenic low back pain, the natural history of such pain should be known beforehand. However, until now, no pathological characteristic could be used to predict the disease course of low back pain. Objective: To better instruct the clinical treatment of discogenic low back pain, a prospective clinical study was performed to observe the natural history of the disease. Study Design: A prospective clinical study during a 4-year follow-up period. Setting: The study was performed at a spinal center in China. Methods: A total of 279 patients with chronic low back pain were included from June 2006 through October 2007. Using discography, 156 patients (56%) were diagnosed to have discogenic back pain. A 101-point numerical rating scale (NRS) was used to assess the back pain symptoms and the Oswestry Disability Index (ODI) was used to assess lumbar function. Results: Of the 156 patients, 131 (84%) completed the study at 4-year follow-up. At the end of follow-up, 17 patients (13.0%) had their low back pain symptoms alleviated and lumbar function improved; 10 patients (7.6%) were slightly improved; 16 patients (12.2%) had their symptoms aggravated; and 88 patients (67.2%) experienced the same pain and disability as before. Although the average NRS and ODI scores obtained during the 4-year follow-up study gradually decreased, statistical significances were found in such changes (P < 0.05,and P < 0.05, respectively); however, the improvement rates of both pain (7.6%) and disability (5.2%) were very low. Limitations: The shortcoming of this study is its relatively small sample size. Conclusion: The present study indicated that the natural history of discogenic low back pain was chronic but persistent, and that the pain and disability in most patients did not improve over time. Key words: Discogenic low back pain, chronic low back pain, lumbar discography, painful disc, black disc, disc degeneration, internal disc disruption, natural history, prognosis.

Poster 415 Radiofrequency Ablation of the Gray Rami Communicans for Refractory Discogenic Low Back Pain in a Combat Veteran: A Case Report

Poster 415 Radiofrequency Ablation of the Gray Rami Communicans for Refractory Discogenic Low Back Pain in a Combat Veteran: A Case Report

Diagnostic and therapeutic value of intradiscal steroid injection in patients with discogenic low back pain combined with radial fissure of annulus fibrosis

Objective To retrospectively investigate diagnostic and therapeutic value of intradiscal steroid injection in patients with discogenic low back combined with radial fissure of annulus fibrosis.Methods Totally 120 patients who had undergone CT guided intervertebral discography and steroid injections,including 72 males and 48 females,aged from 25 to 60 years (average,48 years),were recruited to this study.According to Dallas discography description system,7 cases were rated as grade 0,36 grade 1,48grade 2,and 29 grade 3.The Visual Analogue Scale (VAS) and Roland Morris Disability Questionnaire (RMDQ) were used to evaluate clinical effect at 2 weeks,2 months,6 months,12 months and 24 months postoperatively.Results Most of patients who underwent steroid injection in single highly suspect diseased claimed significant symptom improvement.There were statistically significant differences between pre- and post-operative VAS and RMDQ.The clinical effect in grade 3 group was better than those in grade 1 and grade 2 groups,and the differences were significant.Patients with severe disc disruption (grade 3) had a lower recurrence rate of low back compared with other patients.Conclusion Intradiseal steroid injection not only can significantly relieve discogenic low back pain,but also can benefit diagnosis of discogenic low back pain,especially in patients who fail to reproduce concordant pain on discography.For patients with severe rupture of the annulus fibrosus,the relief of discogenic low back is more significant. Key words: Low back pain; Intervertebral disk; Blocking therapy

The mid-term follow-up results of artificial disc replacement for discogenic low back pain

Objective To evaluate the mid-term clinical and radiographic results of artificial disc replacement (ADR) for discogenic low back pain.Methods From July 2004 to July 2007,21 patients with discogenic low back pain,aged from 26 to 67 years,underwent lumbar ADR with the Charite Ⅲ artificial disc at 22 levels and Activ L prosthesis at 2 levels:L4-5 5 cases,L5S1 13 cases,L4-5 and L5S1 3 cases.The diagnosis was proved by discography in all the patients.The clinical and radiographic results were evaluated and compared between pre-,post-operation and finial follow-up.Results All patients were followed up for 4to 7 years (average,5.1 years).There were statistical differences between pre-operation and final follow-up in Oswestry disability index and Visual Analogue Scale for back pain and leg pain.All the prostheses were mobile without dislocation,breakage,subsidence or spontaneous fusion,only a slight scoliosis was noted in one patient.At the ADR levels,the anterior and posterior intervertebral height increased averagely 6.3 mm and 1.9 mm respectively,the lordosis increased 2.9°,and the mean range of motion (ROM) was 4.6°.At the adjacent level proximal to ADR,the intervertebral height and lordosis decreased slightly,and the ROM decreased 2.5°.The total lumbar lordosis increased 7.8°,and the total lumbar ROM increased 2.4°.According to MRI and CT scans,the degeneration of proximal adjacent disc and facet were not evident,however the degeneration of facets at the ADR levels was evident.Conclusion The 5 years results of ADR for discogenic low back pain were satisfactory,with preserved motion at the ADR level,and the degeneration of adjacent level was not evident.However,there was obvious degeneration in facet joints of the ADR level. Key words: Intervertebral disk; Low back pain; Prostheses and implants; Treatment outcome

Effect of Intradiscal Methylene Blue Injection for the Chronic Discogenic Low Back Pain: One Year Prospective Follow-up Study

ObjectiveTo evaluate the efficacy of intradiscal methylene blue (MB) injection in patients with chronic discogenic low back pain.MethodTwenty patients with discogenic low back pain (4 males, 16 females; mean age 45.6 years) refractory to conservative management were recruited. All subjects underwent MB injection in target lumbar intervertebral discs confirmed by provocative discography. The clinical outcome was assessed by visual analog scale (VAS) and Oswestry disability index (ODI) at baseline and 1, 3, 6 and 12 months after treatment. Successful outcome was described as minimum of 2 points reduction in pain intensity compared with the baseline.ResultsVAS and ODI significantly decreased after one injection. The average VAS and ODI were reduced significantly from 5.1 and 38.0 at baseline to 3.2 and 27.4 at 3 months after injection (p<0.05). However, the mean score of VAS at 12 month follow-up was 4.5 and we could not observe any difference between 12 months after injection and pretreatment. Eleven of twenty patients (55%) reported successful outcomes after intradiscal MB injection at 3 month follow up and the average VAS was reduced by 3.3±1.1 (p<0.05). At the time of 12 month follow up, pain had relapsed in 6 patients who have had satisfactory effect at 3 month follow up. Successful outcome was maintained in only 5 patients (20%) for 1 year.ConclusionThe intradiscal MB injection is a short-term effective minimally invasive treatment indicated for discogenic back pain but it may lose its effectiveness long-term.

Treatment of Discogenic Low Back Pain by Total Disc Arthroplasty using the Prodisc Prosthesis: Analysis of a Prospective Cohort Study with Five- Year Clinical Follow-Up

Few studies are available for the long-term outcome of disc arthroplasty using the Prodisc prostheses. We evaluated if total disc arthroplasty using the Prodisc prosthesis could be a reliable treatment for disabling low-back pain, and if long lasting improvement in quality-of-life could be achieved. We hypothesized that analysis of a prospective cohort study with a mean 5-year follow-up, clinical control, done by rheumatologists not involved in treatment would provide data that was not influenced by surgeon bias. Thirty-nine patients undergoing disc replacement between May 2002 and July 2004 were the study population. Fifty-two levels from L2 to S1, of which 28 were single-level, 9 were double-level and two were three levels, were treated. Independent clinical evaluation by uninvolved rheumatologists was done preoperatively at 1, 2 and 5 years after surgery. The Visual Analogue Score (VAS) for leg and lumbar pain intensity, Oswestry Low Back Pain Disability Index (ODI), Short Form-36 (SF-36), patient satisfaction, and the return to work rate were assessed. Analysis revealed a significant amelioration of the VAS for back and leg pain, as well as for the ODI and the SF-36. Since this is a motion preservation device study it is important to include range of motion ROM analysis at the follow-up times. These data suggest that total disc arthroplasty using the prodisc prosthesis is a good treatment option for disabling discogenic low back pain. The improvement achieved after 1 year could be conserved at 2- and 5-year follow

Stem Cell Microenvironment as a Potential Therapeutic Target

Regenerative MedicineVol. 7, No. 1 EditorialStem cell microenvironment as a potential therapeutic targetCharles C Lee & Kee D KimCharles C LeeMolecular Matrix, Inc. and University of California, Davis, CA, USASearch for more papers by this author & Kee D Kim* Author for correspondenceDepartment of Neurological Surgery, Davis School of Medicine, University of California, Sacramento, CA 95817, USA. Search for more papers by this authorEmail the corresponding author at kdkim@ucdavis.eduPublished Online:15 Dec 2011https://doi.org/10.2217/rme.11.104AboutSectionsView ArticleView Full TextPDF/EPUB ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinkedInReddit View articleKeywords: injurymicroenvironmentnicherepairstem cellReferences1 Yoon YS, Lee N, Scadova H. Myocardial regeneration with bone-marrow-derived stem cells. Biol. Cell.97,253–263 (2005).Crossref, Medline, CAS, Google Scholar2 Sadat S, Gehmert S, Song YH et al. The cardioprotective effect of mesenchymal stem cells is mediated by IGF-I and VEGF. Biochem. Biophys. Res. Commun.363,674–679 (2007).Crossref, Medline, CAS, Google Scholar3 Corti S, Locatelli F, Donadoni C et al. Neuroectodermal and microglial differentiation of bone marrow cells in the mouse spinal cord and sensory ganglia. J. Neurosci. Res.70,721–733 (2002).Crossref, Medline, CAS, Google Scholar4 Wright KT, El Masri W, Osman A, Chowdhury J, Johnson WE. Concise review: bone marrow for the treatment of spinal cord injury: mechanisms and clinical applications. Stem Cells29,169–178 (2011).Crossref, Medline, CAS, Google Scholar5 Xue X, Pech NK, Shelley WC, Srour EF, Yoder MC, Dinauer MC. Antibody targeting KIT as pretransplantation conditioning in immunocompetent mice. Blood116,5419–5422 (2010).Crossref, Medline, CAS, Google Scholar6 Davis ME, Hsieh PC, Grodzinsky AJ, Lee RT. Custom design of the cardiac microenvironment with biomaterials. Circ. Res.97,8–15 (2005).Crossref, Medline, CAS, Google Scholar7 LaBarge MA, Nelson CM, Villadsen R et al. Human mammary progenitor cell fate decisions are products of interactions with combinatorial microenvironments. Integr. Biol. (Cambridge)1,70–79 (2009).Crossref, Medline, CAS, Google ScholarFiguresReferencesRelatedDetailsCited ByBiologics: Inherent Challenges1 April 2021Biologics: Inherent Challenges22 August 2020Stem and progenitor cell microenvironment for bone regeneration and repairCharles C Lee, Naoki Hirasawa, Katrina G Garcia, Dinesh Ramanathan & Kee D Kim8 August 2019 | Regenerative Medicine, Vol. 14, No. 7Laminin-511 Supplementation Enhances Stem Cell Localization With Suppression in the Decline of Cardiac Function in Acute Infarct RatsTransplantation, Vol. 103, No. 5Stem Cells and Discogenic Low Back PainSPINE, Vol. 41Novel aspects of parenchymal-mesenchymal interactions: from cell types to molecules and beyond12 January 2013 | Cell Biochemistry and Function, Vol. 31, No. 4 Vol. 7, No. 1 Follow us on social media for the latest updates Metrics Downloaded 994 times History Published online 15 December 2011 Published in print January 2012 Information© Future Medicine LtdKeywordsinjurymicroenvironmentnicherepairstem cellFinancial & competing interests disclosureCC Lee is currently a chief executive officer of Molecular Matrix, Inc., which may use stem cells for therapeutic applications. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.No writing assistance was utilized in the production of this manuscript.PDF download

Primary results of the 3-in-1 technique of Disc-FX system for the discogenic low back pain

Objective To investigate the clinical efficacy of the 3-in-1 technique of Disc-FX system,namely:discectomy,radiofrequency ablation and annuloplasty for discogenic low back pain in the early stage.Methods From February 2010 to February 2011,40 patients with the discogenic low back pain underwent discectomy,radiofrequency ablation and annuloplasty using Disc-FX system were retrospectively analyzed,including 22 males and 18 females with an average age of 38.7 years (range,32-58 years).The visual analogue scale (VAS) scoring was applied to evaluate the back and low limb pain at preoperative,postoperative 1week,3 months,6 months,and last follow-up.The Macnab score was also evaluated at last follow-up.Results All the patients were followed up for average 13.8 months (range,6-18 months).The operative time averaged 26 min (range,20-40 min).No surgical complication was found during the follow-up.The VAS of preoperative low back pain was 6.60±1.47,VAS score of low back pain at postoperative 1 week,3 months,6 months,and final follow-up were 1.05±0.68,1.15±0.70,1.00±0.62,0.95±0.63,respectively.The postoperative VAS of low back pain decreased significantly compared with that preoperative.The VAS of preoperative limb pain was 3.05±1.23,VAS score of limb pain at postoperative 1 week,3 months,6 months,and final follow-up after operation were 1.10±0.74,1.15±0.70,1.10±0.72,0.95±0.54,respectively.The postoperative VAS of limb pain decreased significantly compared with that preoperative.The evaluation of Macnab score were excellent in 20 patients,good in 17,fair in 2,and poor in 1,suggesting an effective rate of 92.5％ (37/40).Conclusion Disc-FX system,which combined three surgical technique in one procedure,provides a new choice for orthopedics to treat discogenic low back pain.It can give satisfactory clinical outcomes during a short-term followup,but the long term clinical outcomes remains unknown. Key words: Low back pain; Diskectomy, percutaneous; Catheter ablation

Surgical Versus Nonsurgical Treatment of Selected Patients With Discogenic Low Back Pain

Low back pain (LBP) is a common clinical problem and is of major socioeconomic importance. Although any of the spinal structures (intervertebral discs, facet joints, vertebral bodies, ligaments, and muscles) may be a source of LBP, the most likely cause is a lumbar intervertebral disc.1–3 Many autho

Significance of High-intensity Zone of Lumbar Intervertebral Disc on MRI in Diagnosing Discogenic Low Back Pain

Objective To discuss the correlation of high-intensity zone (HIZ)of lumbar intervertebral disc on MRI and discogenic Iow back pain. Metbods To choose 22 cases low back pain patients from April 2009 to November 2010,all the patients had treated with the expectant treatment but were of no effects , and no lumbar disc protrusions on CT, and to be checked by MRI and lumbar discography.To evaluate the value of high-intensity zone(HIZ) of lumbar intervertebral disc on MRI and discogenic low back pain. Results 22 cases low back pain patients had 68 intervertebral disks would be done the lumbar discography, 26 intervertebral disks had reproduce pain reactions, and 12 intervertebral disks were showing high-intensity zone. The intervertebral disks in 12 high-intensity zones were all appearing 2 to3 degree broken annulus fibrosus and reproduce pain reactions .Conclusion The low back pain patients with no lumbar disc protrusions on MRI in diagnosing, there are intervertebral disks in high-intensity zone, to account for the intervertebral disk is to produce the painful broken annulus fibrosus, and also to indicate the HIZ can be diagnose discogenic low back pain. Key words: Discogenic low back pain; Lumbar discography; Magnetic resonance imaging; High-intensity zone

Commentary on an article by Peter G. Passias, MD, et al.: “Segmental Lumbar Rotation in Patients with Discogenic Low Back Pain During Functional Weight-Bearing Activities”

While extensive in vitro and in vivo work has been performed in the area of spinal biomechanics1, correlation of biomechanical data with the symptoms reported by patients is difficult. The authors of this study attempted to combine clinical and biomechanical information by measuring spinal range of motion during functional activities in patients with a history of symptomatic degenerative disc disease. The study improves on previous work as it was limited to the assessment of patients with pain thought to be primarily discogenic. While degenerative disc disease as a cause of back pain, discography as a diagnostic tool, and spinal surgery as a treatment are all controversial, the authors attempted to streamline patient selection and to correlate symptoms with the limited disc-assessment tools available today: MRI, radiography/fluoroscopy, …

Segmental Lumbar Rotation in Patients with Discogenic Low Back Pain During Functional Weight-Bearing Activities

Little information is available on vertebral motion in patients with discogenic low back pain under physiological conditions. We previously validated a combined dual fluoroscopic and magnetic resonance imaging system to investigate in vivo lumbar kinematics. The purpose of the present study was to characterize mechanical dysfunction among patients with confirmed discogenic low back pain, relative to asymptomatic controls without degenerative disc disease, by quantifying abnormal vertebral motion. Ten subjects were recruited for the present study. All patients had discogenic low back pain confirmed clinically and radiographically at L4-L5 and L5-S1. Motions were reproduced with use of the combined imaging technique during flexion-extension, left-to-right bending, and left-to-right twisting movements. From local coordinate systems at the end plates, relative motions of the cephalad vertebrae with respect to caudad vertebrae were calculated at each of the segments from L2 to S1. Range of motion of the primary rotations and coupled translations and rotations were determined. During all three movements, the greatest range of motion was observed at L3-L4. L3-L4 had significantly greater motion than L2-L3 with left-right bending and left-right twisting movements (p < 0.05). The least motion occurred at L5-S1 for all movements; the motion at this level was significantly smaller than that at L3-L4 (p < 0.05). Range of motion during left-right bending and left-right twisting at L3-L4 was significantly larger in the degenerative disc disease group than in the normal group. The range of motion at L4-L5 was significantly larger in the degenerative group than in the normal group during flexion; however, the ranges of motion in both groups were similar during left-to-right bending and left-to-right twisting. The greatest range of motion in patients with discogenic back pain was observed at L3-L4; this motion was greater than that in normal subjects, suggesting that superior adjacent levels developed segmental hypermobility prior to undergoing fusion. L5-S1 had the least motion, suggesting that segmental hypomobility ensues at this level in patients with discogenic low back pain.

Percutaneous Laser Disk Decompression Combining Ozone Nucleus Gelatinosus Oxidizing Technique Treats Discogenic Low Back Pain

Objective To explore the therapeutic effect of treatments with Percutaneous Laser Disk Decompression( PLDD ) combining ozone nucleus gelatinosus oxidizing technique in Discogenic Low Back Pain ( DLBP ). Methods The spinal needle was inserted in the space of the nucleus gelatinosus under X-ray guidance.74 patients with 95 lumbar disks were treated by pulsed-wave mode laser cutting and vaporizing ( with the power of 600 ～ 1000 J for each lumbar disk ) and O3( 5～8 ml with concentration of 60μ g/ml influxed ).Results According to Macnab's standard, among the total 74 patients with the followup of 5 to 36 months, 64 patients had excellent therapeutic effects, 6 patients had good therapeutic effects,4 patients had some therapeutic effects and no one had no therapeutic effects. The total excellent and good effective rate is 94.6%. Conclusion The PLDD combining ozone nucleus gelatinosus oxidizing technique treats DLBP, with advantages of good therapeutic effect, easy operation, little injury, high safety and fast recovery. Key words: Percutaneous Laser Disk Decompression ( PLDD ); Ozone; Discogenic Low Back Pain( DLBP ); Therapeutic alliance

6-Month Results of Transdiscal Biacuplasty on Patients with Discogenic Low Back Pain: Preliminary Findings

Prospective observational study. Our aim is to investigate the efficacy and safety of TransDiscal Biacuplasty. Chronic discogenic pain is one of the leading causes of low back pain; however, the condition is not helped by most non-invasive methods. The results of major surgical operations for these patients are unsatisfactory. Recently, attention has shifted to disk heating methods for treatment. TransDiscal Biacuplasty is one of the minimally invasive treatment methods. The method was developed as an alternative to spinal surgical practices and Intradiscal Electrothermal Therapy for treatment of patients with chronic discogenic pain. The candidates for this study were patients with chronic discogenic pain that did not respond to conservative treatment. The main criteria for inclusion were: the existence of axial low back pain present for 6 months; disc degeneration or internal disc disruption at a minimum of one level, and maximum of two levels, in MR imaging; and positive discography. Physical function was assessed using the Oswestry Disability Index when measuring the pain with VAS. Patient satisfaction was evaluated using a 4-grade scale. Follow-ups were made 1, 3, and 6 months after treatment. 15 patients were treated at one or two levels. The mean patient age was 43.1 ± 9.2 years. We found the mean symptom duration to be 40.5 ± 45.7 months. At the sixth month, 57.1% of patients reported a 50% or more reduction in pain, while 78.6% of patients reported a reduction of at least two points in their VAS values. In the final check, 78.6% of patients reported a 10-point improvement in their Oswestry Disability scores compared to the initial values. No complications were observed in any of the patients. TransDiscal Biacuplasty is an effective and safe method.

Lumbar Facet Joint Motion in Patients with Discogenic Low Back Pain

Lumbar Facet Joint Motion in Patients with Discogenic Low Back Pain

The Efficacy of Spinal Decompression via DRX3000 Combined with a Spinal Mobilization and a Lumbar Stabilization Exercise Program for Patients with Discogenic Low Back Pain

[Purpose] The purpose of this study was to determine the effects of motorized spinal decompression using the DRX3000 system (Axiom Worldwide, Tampa, FL, USA) combined with spinal mobilization as well as lumbar stabilization exercises on patients with discogenic low back pain (LBP). [Subjects] A total of 30 adults with discogenic LBP (mean age, 34.06 ± 6.41 years; age range, 28-48 years; 14 males, 16 females) volunteered to participate in this study. [Methods] A 4-week course of spinal decompression treatment combined with motorized flexion-distraction mobilization and lumbar stabilization exercises were administered to the participants for 6 days per week for the first two weeks, and four times per week for two additional weeks. The entire treatment consisted of 20 visits over a 4-week period. Comparisons of changes in the Oswestry Disability Index (ODI) and straight leg raise (SLR) test at pre-intervention, after 10 treatment sessions, and at discharge (after 20 treatment sessions) were analyzed. [Results] There were significant improvements in the outcome measures of ODI score and SLR test after 10 and 20 sessions of spinal decompression treatment combined with spinal mobilization and lumbar stabilization exercises as compared with the pre-intervention. [Conclusion] Spinal decompression treatment combined with spinal mobilization and lumbar stabilization exercises significantly improved the clinical outcome measures of ODI score and SLR test in patients with LBP secondary to intervertebral disc herniation.

Complete Freund’s Adjuvant-Induced Intervertebral Discitis as an Animal Model for Discogenic Low Back Pain

Although numerous animal models for low back pain associated with intervertebral disk (IVD) degeneration have been proposed, insufficient data have been provided to make any conclusions regarding pain. Our aim in this study was to determine the reliability of complete Freund's adjuvant (CFA) injection into the rat spine as an animal model representing human discogenic pain. We studied IVD degenerative changes with pain development after a 10-microL CFA injection into the L5-6 IVD of adult rats using behavioral, histologic, and biochemical studies. Serial histologic changes were analyzed to detect degenerative changes. Expression of calcitonin gene-related peptide (CGRP), prostaglandin E (PGE), and inducible nitric oxide synthase (iNOS) were determined using immunohistochemistry or real-time polymerase chain reaction as support data for pain development. In addition, CGRP immunoreactivity (ir) at the IVD was considered indirect evidence of neural ingrowth into the IVD. There was a significant increase of the hindpaw withdrawal response in the CFA group until 7 wk postoperatively (P < 0.05). Histologic analyses revealed progressive degenerative changes of the disks without any damage in adjacent structures, including nerve roots. In the CGRP-ir staining study, the bilateral dorsal horns and IVD had positive ir after intradiscal CFA injection. CGRP mRNA expression was increased in the dorsal root ganglion (DRG) at 2 and 4 wk, whereas PGE and iNOS mRNAs were markedly increased at 2 wk. The increment of CGRP expression was higher in allodynic rats compared with nonallodynic rats. Intradiscal CFA injection led to chronic disk degeneration with allodynia, which was suggested by pain behavior and expression of pain-related mediators. The increment of CGRP, PGE, and iNOS also suggest pain-related signal processing between the IVD and the neural pathway in this animal model. This animal model may be useful for future research related to the pathophysiology and development of novel treatment for spine-related pain.

Results of Surgery for Discogenic Low Back Pain

Randomized, controlled study. To evaluate the diagnosis of discogenic low back pain (LBP) with discography and discoblock. Discogenic LBP is usually diagnosed by magnetic resonance imaging and discography. However, the reliability of discography is controversial. Previously, we reported the usefulness of discoblock with bupivacaine for diagnosis, and discoblock improved the results of anterior interbody fusion surgery. However, that study was not a randomized, controlled study. Therefore, the purpose of the current study was to compare the results of surgery after diagnosis of LBP by discography and discoblock. Patients (n = 42) with severe LBP showing L4-L5 or L5-S1 disc degeneration on magnetic resonance imaging were evaluated by discography (1.5 mL of contrast medium) or discoblock (intradisc injection of 0.75 mL of 0.5% bupivacaine). We randomized the patients in turn. Anterior discectomy and interbody fusion were performed in patients who responded to the diagnostic procedures. The visual analogue scale score (0, no pain; 100, worst pain), Japanese Orthopedic Association Score (0, worst pain; 3, no pain), Oswestry Disability Index, and patient satisfaction before and 3 years after surgery were recorded and compared between groups. Twelve patients did not show pain provocation by discography or pain relief by discoblock and were excluded. Fifteen patients who showed pain provocation by discography and 15 patients who experienced pain relief with discoblock were evaluated. Rates of improvement in the visual analogue scale score, Japanese Orthopedic Association Score, and Oswestry Disability Index score in the discoblock group were significantly higher than those in the discography group (P < 0.05) from baseline to 3 years after surgery. Three patients were dissatisfied with surgery after discography compared with one patient after discoblock. Pain relief after injection of a small amount of bupivacaine into the painful disc was a useful tool for the diagnosis of discogenic LBP compared with discography.

The relationship between discography pressure and outcome of anterior lumbar interbody fusion for discogenic low back pain.

Objective To explore the relationship between discography pressure and outcome of an-terior lumbar interbody fusion (ALIF) for discogenic low back pain. Methods From April 2004 to June 2006, 65 patients with chronic low back pain were identified as diseogenic origin by pressure controlled discography, 22 cases of which received ALIF after failed conservative treatment for at least 6 months. The surgically treated patients aged 43.6 on the average (range, 25-67). The treated discs located: 8 in L4-5, 12 in L5S1, 2 in both L4-5 and L5S1. 22 cases received ALIF in 24 levels via retroperitoneal approach. The pressure as soon as accordant initially induced pain was recorded during discography. Low pressure (pressure ≤ 300kPa) in 10 cases and high pressure (pressure 300-500 kPa) in 12 cases. At 3 days postoperative, the patients were allowed to leave bed with a brace, and the brace should be used for 3 months. Results All the cases were followed up for average 18 months (range, 6-26 months). At the end of follow-up all the patients recov-ered normal social life and work without any symptoms. Disc height increased from 9.5 mm preoperatively to 13.5 mm postoperatively. Surgery time averaged 90 rain (70-120 rain); blood loss averaged 220 ml (100-400ml). Low pressure group and high pressure group showed no significant different in VAS, ODI, disc height,surgery time and blood loss preoperatively. At 6 months follow up, VAS and ODI improve rates of low pres-sure group account for 82.4% and 90.1% respectively; and those of high pressure group account for 71.7%and 80.6% respectively. No ileus, retrograde ejaculation nor artificial disc translation was noticed during fol-low-up. Conclusion Pressure-controlled discography can increase the diagnostic accuracy of discogenic lowback pain, and a positive discography on low pressure indicates better surgical outcome. Key words: Lumbar vertebrae; Intervertebral disk; Pain; Pressure