Recurrent Disc Herniation Research Articles

Mini-open Anterior Lumbar Interbody Fusion for Recurrent Lumbar Disc Herniation Following Posterior Instrumentation.

A retrospective study. The aim of this study is to evaluate, clinically and radiographically, the efficacy of mini-open retroperitoneal anterior lumbar discectomy followed by anterior lumbar interbody fusion (ALIF) for recurrent lumbar disc herniation following primary posterior instrumentation. Recurrent disc herniation following previous disc surgery occurs in 5 to 15% of cases. This is often treated by further surgical intervention where posterior approach is generally preferred. However, posterior surgery may be problematic if the initial surgery involved posterior instrumentation. An anterior approach may be indicated in these patients, and recent findings suggest that a "mini-open" procedure may have some benefits when compared with traditional open techniques and their associated morbidities. A total of 35 recurrent lumbar disc herniation patients (10 male, 25 female) following primary posterior instrumentation with an average age of 52.8 years (range: 34-70 yrs) who underwent the mini-open ALIF procedures between August 2001 and February 2012 were evaluated retrospectively. The ALIF was performed at the levels L4-L5 (n = 14), L5-S1 (n = 15), or both L4-L5 and L5-S1 (n = 6). Visual Analog pain Scale (VAS) and Oswestry Disability Index (ODI) together with radiological results were assessed. The mean operating time, intraoperative estimated blood loss, and hospital stay were 115 minutes, 70 mL, and 6 days, respectively. No blood transfusion was needed. Transient complication was recorded in two patients. Postoperative follow-up was a minimum 24.3 months. VAS score and ODI percentage decreased significantly from 7.9 ± 0.8 and 78.8% ± 12.4% pre-operatively to 1.4 ± 0.6 and 21.7 ± 4.2% at final follow-up, respectively. There was no neurological worsening and radicular pain improved significantly compared with pre-operation in all the patients. Computed tomographic reconstruction 12 and 24 months after surgery showed bony fusion, normal position, and morphology of the fusion cage in all patients. Mini-open retroperitoneal ALIF is an effective treatment for patients with recurrent lumbar disc herniation following primary posterior instrumentation. 4.

Retrospective analysis of perioperative complications and risk factors of posterior lumbar interbody fusion for recurrent lumbar disc herniation

Objective To retrospectively analyze the perioperative complications of posterior lumbar interbody fusion (PLIF) for recurrent lumbar disc herniation and identify potential risk factors that correlate with those complications. Methods All of 71 patients with recurrent lumbar disc herniation were treated surgically with PLIF, discharged from our department between January 2008 and December 2014. Demographic and operation data were collected and perioperative complications were recorded. We analyzed whether the clinical factors (age, gender, BMI, co-morbidity, smoking, time of recurrence, blood loss, operation segment, operation time) were in correlation with perioperative complication by univariate analysis. Then we integrated the statistically significant indicators into Logistic regression equation to determine the related risk factors for complication. Results The study group consisted of 71 cases, including 42 males and 29 females. The age was 19 to 64 years old with an average of 50.6 years old, and the average BMI was 23.6 kg/m2. 26 cases had perioperative complications, while there were two or more complications in 5 patients, and no mortalities. Neurologic deterioration or neuropathic pain (10 cases, 14.1%) and dural tears (6 cases, 8.5%) were the most common intraoperaitive complications. The other complications included nerve root or cauda equine injury, deep or superficial wound infection, urinary tract infection, respiratory system complication, cardio-vascular complication and delirium. Univariate analysis suggested that age, gender, co-morbidity, smoking, time of recurrence, operation segment, operation time were not associated with perioperative complication. The multivariate Logistic regression analysis showed BMI and blood loss were closely related to perioperative complication. Conclusion Complications of posterior spinal fusion surgery for recurrent lumbar disc herniation are affected by many factors. The most common complications are transient neurologic deterioration or neuropathic pain and dural tears. BMI and blood loss are independent risk factors. Key words: Lumbar vertebrae; Intervertebral disc displacement; Recurrence; Intraoperative complications; Postoperative complications; Risk factors

Which level is responsible for gluteal pain in lumbar disc hernia?

BackgroundThere are many different reasons why patients could be experiencing pain in the gluteal area. Previous studies have shown an association between radicular low back pain (LBP) and gluteal pain (GP). Studies locating the specific level responsible for gluteal pain in lumbar disc hernias have rarely been reported.MethodsAll patients with lumbar disc herniation (LDH) in the Kanghua hospital from 2010 to 2014 were recruited. All patients underwent a lumbar spine MRI to clarify their LDH diagnosis, and patients were allocated to a GP group and a non-GP group. To determine the cause and effect relationship between LDH and GP, all of the patients were subjected to percutaneous endoscopic lumbar discectomy (PELD).ResultsA total of 286 cases were included according to the inclusive criteria, with 168 cases in the GP group and 118 cases in the non-GP group. Of these, in the GP group, 159 cases involved the L4/5 level and 9 cases involved the L5/S1 level, while in the non-GP group, 43 cases involved the L4/5 level and 48 cases involved the L5/S1 level. PELD was performed in both groups. Gluteal pain gradually disappeared after surgery in all of the patients. Gluteal pain recrudesced in a patient with recurrent disc herniation (L4/5).ConclusionsAs a clinical finding, gluteal pain is related to low lumbar disc hernia. The L4/5 level is the main level responsible for gluteal pain in lumbar disc hernia. No patients with gluteal pain exhibited involvement at the L3/4 level.Electronic supplementary materialThe online version of this article (doi:10.1186/s12891-016-1204-7) contains supplementary material, which is available to authorized users.

Comparing clinical outcomes of repeat discectomy versus fusion for recurrent disc herniation utilizing the N2QOD

OBJECTIVE Recurrent lumbar disc herniation (RLDH) is a significant cause of morbidity in patients undergoing lumbar discectomy and has been reported to occur in up to 18% of cases. While repeat discectomy is often successful in treating these patients, concern over repeat RLDH may lead surgeons to advocate instrumented fusion even in the absence of instability. The authors' goal was to compare clinical outcomes for patients undergoing repeat discectomy versus instrumented fusion for RLDH. METHODS The authors used the National Neurosurgery Quality and Outcomes Database (N2QOD) to assess outcomes of patients who underwent repeat discectomy versus instrumented fusion at a single institution from 2012 to 2015. Primary outcomes included Oswestry Disability Index (ODI) score, visual analog scale (VAS) score, and quality-adjusted life year (QALY) measures. Secondary outcomes included hospital length of stay, discharge status, and hospital charges. RESULTS The authors identified 25 repeat discectomy and 12 instrumented fusion patients with 3- and 12-month follow-up records. The groups had similar ODI and VAS scores and QALY measurements at 3 and 12 months. Patients in the instrumented fusion group had significantly longer hospitalizations (3.7 days vs 1.0 days, p < 0.001) and operative times (229.6 minutes vs 82.7 minutes, p < 0.001). They were also more likely to be female (p = 0.020) and to be discharged to inpatient rehabilitation instead of home (p = 0.036). Hospital charges for the instrumented fusion group were also significantly higher ($54,458.29 vs $11,567.05, p < 0.001). Rates of reoperation were higher in the repeat discectomy group (12% vs 0%), but the difference was not statistically significant (p = 0.211). CONCLUSIONS Repeat discectomy and instrumented fusion result in similar clinical outcomes at short-term follow-up. Patients undergoing repeat discectomy had significantly shorter operative times and length of stay, and they incurred dramatically lower hospital charges. They were also less likely to require acute rehabilitation postoperatively. Further research is needed to compare these two management strategies.

The clinical application of "jetting suture" technique in annular repair under microendoscopic discectomy: A prospective single-cohort observational study.

To introduce a new designed suture technique in annular repair under the microendoscopic discectomy (MED) surgery and to evaluate the clinical application of the technique in annular repair under MED with at least 2-year follow-up period.A new method of annular repair was designed and named “jetting suture” technique. Thirty consecutive patients with lumbar disc herniation were enrolled in the prospective single-cohort observational study. Patients were followed up at intervals of preoperative, postoperative 1 week, 3 months, 6 months, 1 year, and last follow-up. The clinical outcomes were evaluated by using Japanese Orthopaedic Association (JOA) score, Oswestry Disability Index, and modified Mcnab criteria.The procedure was successfully performed in all cases. No case required conversion to an open procedure. The mean age of patients was 36.6 years. Average blood loss was 45.8 ± 10.2 mL. The preoperative symptoms were alleviated significantly after surgery. All the standardized measures improved significantly at the last follow-up, including JOA score (10.1 to 26.6; P < 0.05) and Oswestry Disability Index (75.3 to 9.6; P < 0.05). Improvement rate of JOA score was 86.4%. Approximately 83.4% of patients reported good or excellent outcomes based on modified Mcnab criteria. No postoperative complication and recurrence of disc herniation was reported.The designed “jetting suture” technique in annular repair under MED can be performed safely and effectively. It could be a viable alternative to annular repair under lumbar discectomy.

Anatomical characteristics and surgical selections of upper lumbar disc herniation

To explore the anatomical characteristics and surgical selections of upper lumbar disc herniation, and evaluate its clinical effects. From January 2009 to January 2013, 26 patients with upper lumbar disc herniation were treated in our department. There were 16 males and 10 females, aged from 28 to 51 years old with an average of 45.7 years, 4 cases were in L₁,₂, 9 cases in L₂,₃, and 13 cases in L₃,₄. The data was collected including distance between outer edge of lower facet and the spinous process, the outer edge of the isthmus and spinous process, the lower edge of lamina and the upper edge of the intervertebral space, nerve root arising points and lower edge of the corresponding pedicle. Transforaminal discectomy and interbody fusion combined with pedicle screw fixation was performed in patients with L₁,₂, L₂,₃ herniated disk and 5 patients with L₃,₄ herniated disk complicated with lumbar instability. However another 8 patients with L₃,₄ herniated disk were treated with posterior fenestration decompression. Clinical effects were evaluated by Japanese Orthopaedic Association(JOA). The relative height rate(R) of the intervertebral space was measured preoperatively and 1 year postoperatively. The fusion of the bone graft was also observed. Intraoperative anatomical measurement was taken in all patients. All patients were followed up for more than 1 year with an average of 16 months, and all incisions got healing, JOA was improved from preoperative(10.13±1.49) points to last follow up (25.21±2.13) points with the improvement rate of 79.9%. Among the patients underwent fusion operation, 17 cases obtained bone fusion and 1 case maybe non fusion and no internal fixation failure was found;the R value was (0.231±0.056) mm preoperatively, however (0.345±0.076) mm at 1 year after operation with statistical difference(P<0.05). In the patient underwent posterior fenestration decompression, the R value was(0.243±0.036) mm preoperatively, and (0.212±0.046) mm at 1 year after operation without statistical difference (P>0.05). No spinal instability and lumbar disc herniation recurrence were found in these patients. According to the anatomical characteristics of L₁,₂ and L₃,₄ herniated disk, these patients could be treated with transforaminal discectomy and interbody fusion. The anatomical characteristics and clinical manifestations of L₃,₄ herniated disk is similar with the lower lumbar disc herniation, for the patients, an appropriate surgical method should be chosen according to the lumbar stability.

Microsurgical posterior cervical foraminotomy: a study of 181 cases

Background: An unsettled controversy over the appropriate surgical approach in cases of cervical radiculopathy caused by degenerative vertebrae and intervertebral discs is still present. The purpose of this study is to examine the efficacy of microsurgical posterior foraminotomy in the treatment of cervical radiculopathy and to find out whether the underlying pathology (soft disc herniation/spondylosis) is of value in predicting long-term outcome after this procedure.Methods: Patients, who underwent posterior cervical foraminotomy (PCF) at our department between 2006 and 2013 for unilateral mono-segmental lateral soft disc herniation, or spondylosis, or both, were enrolled in this study. Demographic, clinical and surgical data were retrospectively reviewed. The patients were subsequently interviewed by telephone to identify their long-term outcome. The clinical outcomes were evaluated using Odom’s criteria. Descriptive statistics were frequencies and percentage of occurrence for categorical variables and mean and range for continuous variables.Results: One hundred eighty-one patients were included in this study, with a median follow-up of 58 months (mean 43 months, range 12–96 months). The overall re-operation rate was 7.2% (13 patients); 11 patients (6%) for recurrent root symptoms due to recurrent disc herniation (six patients, 3.3%) and re-stenosis (five patients, 2.8%), one patient (0.55%) for wound infection and one patient (0.55%) for postoperative haematoma. Among the eleven patients who underwent re-operation for recurrent root symptoms there was one patient who additionally had persistent cerebrospinal fluid leak and superficial posterior wound infection. There was no significant difference between lateral soft disc herniation and spondylosis in term of re-operation rate. At discharge, excellent or good outcome was achieved in 89% of patients; the long-term success rate was 97.2% using Odom’s criteria.Conclusion: Microsurgical PCF is an effective technique for treating lateral spinal root compression. Proper patient selection is obligatory to achieve the best results.

Treatment of Recurrent Disc Herniation: A Systematic Review.

Intervertebral disc herniation is one of the most common causes of back and extremity pain. The most commonly used surgical treatment is lumbar discectomy. About 0.5-25% go on to develop recurrent disc herniation (rDH) after a successful first discectomy. Currently, there aren’t any guidelines to assist surgeons in determining which approach is most appropriate to treat rDH. A recent survey showed significant heterogeneity among surgeons regarding treatment options for rDH. It remains unclear which methods lead to better outcomes, as there are no comparative studies with a sufficient level of evidence. In this study, we aimed to perform a systematic review to compare treatment options for rDH and determine if one intervention provides better outcomes than the other; more specifically, whether outcome differences exist between discectomy alone and discectomy with fusion.We applied the PICOS (participants, intervention, comparison, outcome, study design) format to develop this systematic review through PubMed. Twenty-seven papers from 1978-2014 met our inclusion criteria and were included in the analysis. Nine papers reported outcomes after discectomy and seven of them showed good or excellent outcomes (70.60%-89%). Ten papers reported on minimally invasive discectomy. The percent change in visual analog scale (VAS) ranged from -50.77% to -86.57%, indicating an overall pain reduction. Four studies out of the ten reported good or excellent outcomes (81% to 90.2%). Three studies looked at posterolateral fusion. Three studies analyzed posterior lumbar interbody fusion. For one study, we found the VAS percentage change to be -46.02%. All reported good to excellent outcomes. Six studies evaluated the transforaminal lumbar interbody fusion. All reported improvement in pain. Four used VAS, and we found the percent change to be -54% to -86.5%. The other two used the Japanese Orthopedic Association (JOA) score, and we found the percent change to be 68.3% to 93.3%.We did not find enough evidence to support any significant difference in outcomes between discectomy alone and discectomy with fusion. The limitation of our study includes the lack of standardized outcomes reporting in the literature. However, reviewing the selected articles shows that fusion may have a greater improvement in pain compared to reoperation without fusion. Nonetheless, our study shows that further and more in-depth investigation is needed on the of treatment of rDH.

Case Study

INTRODUCTION: Low back pain is a common complaint in pregnancy reported by over 50% of patients, however disc herniation is rare, affecting 1:10,000 pregnancies. Providers must be able to recognize severe and progressive neurological symptoms, like cauda equina syndrome, to prevent long-term sequelae. There are no other cases reported of a vaginal delivery as soon as 6 weeks after spinal surgery. METHODS: Case Study. RESULTS: A 32 yo G4P2 with longstanding back pain developed L5-S1 disc displacement at 32 weeks gestation. Due to progressive neurological dysfunction, she underwent bilateral hemilaminectomy and foraminotomy with L5-S1 discectomy under general anesthesia in the prone position. Her obstetrician scheduled her primary cesarean delivery at 39 weeks due to her spinal surgeon's concern of damaging her recent surgery. She had a precipitous vaginal delivery 1 day prior to her scheduled cesarean and 6 weeks after her surgery. Her back pain symptoms began to return 4 days postpartum and necessitated repeat surgery 4 weeks after delivery due to recurrent L5-S1 disc herniation and lower extremity radiculopathy. CONCLUSION: Data is lacking on the best mode of delivery on patients who have undergone spinal surgery. There are no case reports of vaginal delivery after a spinal surgery as recent as the third trimester. It is unclear whether vaginal delivery was the cause of reherniation in our case report. Cesarean delivery is not necessarily protective as demonstrated by a case report of herniation after scheduled cesarean delivery. We recommend a multidisciplinary team approach to manage patients on a case-by-case basis.

Introducing Interlaminar Full-Endoscopic Lumbar Diskectomy: A Critical Analysis of Complications, Recurrence Rates, and Outcome in View of Two Spinal Surgeons' Learning Curves.

Background and Study Objective Interlaminar full-endoscopic diskectomy is a minimally invasive surgical alternative to microdiskectomy for the treatment of lumbar disk herniation. The authors analyze their surgical results and learning curves during and after the introductory phase of this surgical technique. Patients and Methods We present a case review of 76 patients operated on using interlaminar full-endoscopic diskectomy. We retrospectively analyzed two spinal surgeons' learning curves in terms of operation time with respect to intraoperative blood loss, conversion rates, complications, infections, length of hospitalization, need for rehabilitation, recurrence rates, pain intensity, and opioid use. Patients' functional status and Health-related Quality of Life were assessed by follow-up questionnaires for 47 patients, using the North American Spine Society Score and the Short Form 12 in addition to long-term pain intensity, work capacity, and patient satisfaction with the operation. Results A steady state of the learning curve (operation time) of an experienced spinal surgeon was reached after 40 cases. Supervision by a more experienced surgeon can shorten the learning curve. The rate of conversions (10%), complications (5%), and recurrent lumbar disk herniations (28%) did not negatively affect the long-term outcome in patients operated on before and after the learning phase. Patient satisfaction was high. Conclusions The rate of conversions, complications, and recurrent lumbar disk herniations compared with microdiskectomy combined with the challenging learning curve should be considered before surgeons adopt this procedure. Supervision by an endoscopically experienced spinal surgeon during the introductory phase is highly advisable.

Transforaminal Lumber Interbody Fusion (TLIF) Clinical and Radiological Outcome

Objective To evaluate the clinical and radiological outcome of TLIF in the treatment of Spondylolisthesis, degenerative disc disease and recurrent herniation of lumber disc. Methodology: A retrospective study, between Jan 2009 and December 2011.The patients with chronic back pain (more than 6 months of disability and refractory to conservative management) with or without leg pain / neurological deficit due to degenerative spondylolisthesis, degenerative disc disease and recurrent lumber disc herniation treated with Transforaminal Lumber Interbody Fusion (TLIF) were included. It was a retrospective review of the patient files to assess the pre and postoperative symptomatology, findings on clinical examination, radiological characteristics. The same procedure was performed in all cases by a single spine surgeon. The clinical outcome was assessed using Oswestry Disability Index (ODI) scoring system. Bony fusion was assessed based on a pre-set criteria on plain radiographs at 18 months postoperatively. Results Of 25 there were 16 male (64%) and 9 female (36%) patients with a mean age of 40 years (range: 20–60), who underwent TLIF (Transforaminal Lumber Interbody Fusion). 9 patients diagnosed as degenerative disc disease, 12 with spondylolisthesis and 4 having recurrent disc herniation. Of the 25 patients who underwent TLIF, in 14 (56%) cases fusion was performed at L5-S1, in 9 (36%) at segment L4-L5 and in 2 (8%) at L3-L4. We found subjective improvement in symptoms of back pain in 19 (76.0%) of 25 patients, leg pain in 15 (83.3%) of 18, and 04 (66.67%) &amp; 02(40.0%) improvement in sensory and motor deficit respectively postoperatively. Based on the Oswestry Disability Index (ODI) and Visual Analog Pain Scale (VAS), showed significant improvement from preoperative 7.1 &amp; 42.3 to 2.5 &amp; 17.5 ODI and VAS scores at 18 months postoperatively respectively, with an overall improvement of 4.6 VAS and 24.8 ODI scores. A radiological fusion was observed at 18 months postoperatively on anterio-posterior (AP) and lateral X-rays following the pre set criteria in 23 of 25 patients (92.00%). Conclusion TLIF is a safe and effective method to treat chronic low back pain in patients with spondylolisthesis, degenerative disc disease and recurrent disc herniation. Our results confirm that TLIF is an option that is associated with good clinical and radiological outcome.

Results after Lumbar Discectomy for Herniated Disc in Worker's Compensation Patients: more than 15 Years of Follow- up

Introduction Published literature has identified worker's compensation population to have worse results after lumbar discectomy for herniated disc compared with general population. However the advantage of complete follow-up due to its captive population is well know. This study aims to evaluate lumbar discectomy outcomes, prognostic factors and recurrence rate after more than15 years of follow-up. Material and Methods A retrospective review of 50 worker's compensation patients operated consecutively between 1997–1998 in Hospital del Trabajador for primary herniated lumbar disc was performed. Electronic medical records analysis was conducted until June 2015. Primary outcomes were surgical complications, sick leave, return to work, work compensation, chronic postoperative low back pain and reoperation for recurrent lumbar disc herniation. Statistical analysis looking for prognostic factors in lumbar discectomy evolution was realized. Results We found 44 men and 6 women with a mean age of 36.5 (22–66) years. One hundred percent follow-up was achieved with a mean time of 18 (17.5–18.5) years. Most patients were light workers (58%). Lumbar herniated discs were mostly located at L5-S1 ( n = 35) followed by L4-L5 ( n = 12). 74% were posterolateral disc herniations and 22% were central. Mean preoperative, postoperative and total sick leave was 37.9 (1–109), 57.7 (28–175) and 95.6 (35–203) days respectively. An intraoperative complication rate of 2% was seen, while no infectious complications were reported. All patients returned to work, most of them to the same work (88%). 10% received work compensation. During follow up, 32% (16/50) required a new period of sick leave with a mean sick free time of 64.4 (4–135) months. 8 of these were due to a new episode of low back pain. The rest were 6 recurrent disc herniations and 2 other level disc herniations that required new surgery. At 5, 10 and more than 15 years of follow-up recurrence rate was 8%, 12% and 12% respectively, while chronic low back pain was 8%, 10% and 12% respectively. Psychological disorders found in 18% patients were associated with longer sick leave (62.8 versus 56.6 days. p &lt; 0.05) and higher need of work compensation (33% versus 4.9%, p &lt; 0.05). Patients with preoperative infiltrations (33/50) required more new periods of sick leave (33% versus 5.9%, p &lt; 0.05). Age, type of work, previous low back pain episodes, disc herniation characteristics and preoperative sick leave showed no statistically significant association with postoperative evolution. Conclusion As found in previous study, the presence of physiological disorders, also known as non-organic symptoms, and preoperative infiltrations were associated with worse results after lumbar discectomy. This manifested as longer sick leave periods and higher need of work compensation. Age, type of work, disc herniation characteristics and preoperative sick leave did not represent bad prognostic factors. Disc herniation recurrence rate increased from 8% at 5 years of follow-up to 12% at 10 and over 15 years of follow-up. This recurrence rate is similar to the one reported in literature. Ten percent of postoperative chronic low back pain at 10 years and 12% with more than 15 years of follow-up was observed.

Annular Repair Using High-density Collagen Gel with Riboflavin Crosslinkage: Preliminary Data from an in vivo Ovine Model

Introduction Discectomy of herniated intervertebral discs (IVDs) successfully alleviates neurological symptoms but fails to repair the iatrogenic annulotomy. This persistent annular defect post-discectomy is associated with increased risk of reherniation, progressive IVD degeneration, and chronic low back pain. Previously we demonstrated the ability of high-density collagen (HDC) gels to facilitate annular repair in a rodent model.1,3 This study aims to use HDC gel in an ovine model which has previously been used as a surrogate for the human spine.2 The goal of this study is create an effective ovine model for a herniated nucleus pulposus through a generated annular defect and to show that our HDC helps induce annular repair reduces the degenerative changes. Methods Sheep have had intervertebral discs violated to create an annular defect and induce a herniated nucleus pulposus. These sheep were laid in a lateral position with their right-side up. A longitudinal incision was made from their most caudal rib to their iliac crest 1-cm ventral to their transverse processes. Using a lateral approach, the soft tissue and muscle were dissected of their transverse processes to expose their vertebral bodies. The annular fibrosis (AF) defect was created with a 3.2 mm drill inserted to a 9–11 mm depth and then an 18-gauge needle was inserted to a maximum depth of 9–10 mm to injure the nucleus pulposus (NP) and induce a herniation through the annular defect. The violated IVDs were then randomized to either treatment with riboflavin-crosslinked HDC gel or no treatment. Thus far 4 IVDs were randomized to the control group and 4 IVDs to the treatment group. An in vivo MRI and post-mortem MRI were performed 6 weeks after the surgery to assess the degree of herniation of the nucleus pulposus. A post-mortem X-Ray was also obtained 6 weeks after the surgery to assess for any changes in disc height, which is a surrogate for degenerative disc changes. Results Of the 8 intervertebral disc which we induced an annular defect, we were able to induce nucleus pulposus herniation through the annulotomy in all levels as in the example in Fig. 1 . Our preliminary data so far shows no difference in the disc height index of the intervertebral discs that received HDC versus those that received no treatment at 6 weeks after the surgery. The average disc height index of the treated intervertebral discs was 0.78 ± 0.005, 0.77 ± 0.004 for the untreated, puncture-only intervertebral discs, and 0.82 ± 0.006 for the healthy discs. Conclusion Lumbar discectomy to treat disc herniation is one of the most commonly performed spinal procedures,1 with an estimated 300,000 cases per year in the United States.2 A ~5% to 15% of discectomy cases result in a reherniation of their nucleus pulposus3 through the annulotomy and is associated with compromised patients outcomes and increased health care costs.4 Our preliminary data show that we are able to effectively use an ovine model to simulate a herniated nucleus pulposus via a lateral approach to the lumbar vertebral. Experiments are ongoing to analyze the disc levels using T2 mapping on MRI to assess changes in the NP hydration and overall area as our group has done previously in the rat-tail model.5 If HDC is found to be efficacious in inducing annular repair in a large mammal model, the next step would be to progress to clinical trials in humans. [Figure: see text] References Laus M, Bertoni F, Bacchini P, Alfonso C, Giunti A. Recurrent lumbar disc herniation: what recurs? (A morphological study of recurrent disc herniation). Chir Organi Mov 1993;78(3):147–154 Carragee EJ, Han MY, Suen PW, Kim D. Clinical outcomes after lumbar discectomy for sciatica: the effects of fragment type and anular competence. J Bone Joint Surg Am 2003;85-A(1):102–108 Swartz KR, Trost GR. Recurrent lumbar disc herniation. Neurosurg Focus 2003;15(3):E10 Ambrossi GLG, McGirt MJ, Sciubba DM, et al. Recurrent lumbar disc herniation after single-level lumbar discectomy: incidence and health care cost analysis. Neurosurgery 2009;65(3):574–578, discussion 578 Grunert P, Hudson KD, Macielak MR, et al. Assessment of intervertebral disc degeneration based on quantitative magnetic resonance imaging analysis: an in vivo study. Spine 2014;39(6):E369–E378

Revision Surgery for "Real" Recurrent Lumbar Disk Herniation: A Systematic Review.

A systematic review. To systematically review the previous literature regarding revision surgery for real recurrent lumbar disk herniation. "Real" recurrent lumbar disk herniation means the presence of herniated disk material at the same level and side as the primary disk herniation. If conservative treatment fails, revision surgery, a major concern, is indicated. It is important for both patients and spine surgeons to understand epidemiology trends and outcomes of revision surgery for real recurrent lumbar disk herniation (real-RLDH). The electronic databases PubMed, the Cochrane library, and EMBASE were queried for English articles regarding revision surgery for real-RLDH, published between January 1980 and May 2014. The incidence, interval between primary and revision surgery, risk factors, surgery type, complications, and clinical outcomes of revision surgery for real-RLDH were summarized. The reported incidence of revision surgery, specifically for real-RLDH, lies between 1.4% and 11.4%. The complication rate is reported between 0% and 34.6%, with dural tear being the most common complication. Previous studies revealed that satisfactory or successful clinical outcome was achieved in 60%-100% of patients after revision surgery for real-RLDH. Several studies reported similar clinical outcomes between primary and revision surgery. The incidence of revision surgery for real-RLDH is relatively low. It is essential to pay careful attention to prevent a dural tear. Patients may expect clinical outcomes similar to those following primary discectomy.

Annular Repair Using Cross-Linked High Density Collagen Gel Seeded with Fibrochondrocytes: In Vivo Outcomes of a Rodent Disc Study

Introduction Despite alleviating associated neurological symptoms, discectomy of herniated intervertebral discs (IVDs) fails to repair the underlying degenerative process. Persistent annular defect post discectomy is associated with increased risk of reherniation, progressive IVD degeneration, and chronic low back pain.1–7 Although many studies have previously employed cell transplantation to regenerate the nucleus pulposus (NP), few have focused on annulus fibrosus (AF) repair. Recently, we demonstrated the ability of riboflavin crosslinked high-density collagen gels (HDC) to facilitate annular repair in vivo.8,9 In this study, we assessed the in vivo efficacy of AF fibrochondrocytes seeded in a gel scaffold at enhancing the the repair of an annular defect to prevent further degenerative changes in a post-puncture rat-tail model. Material and Methods 38 athymic rats, punctured with an 18-gauge needle in the tail disc, were divided into 3 groups: untreated ( n = 6), injected with crosslinked HDC ( n = 16), and injected with fibrochondrocyte-laden crosslinked HDC ( n = 16). At 1, 2, and 5 weeks postoperatively, a series of in vivo images with X-ray and 7T MRI were conducted to determine the disc height index and nucleus pulposus (NP) size and hydration, respectively.8,10,11 Histological assessments were performed to evaluate the viability of implanted cells, degree of annular repair and secondary disc degeneration. The study was approved by and undertaken in accordance with guidelines outlined by the Hospital for Special Surgery Institutional Animal Care and Use Committee and New York State. For the analyses of continuous outcomes in disc height index, NP size, and NP hydration, we employed linear regression models with a generalized estimating equation and robust standard errors to estimate differences in mean changes from baseline controls (discectomy) across displaced and stable implantation groups. P values &lt; 0.05 were considered statistically significant. Results The untreated discs showed substantial NP herniation at two weeks and NP absence with signs of degeneration by five weeks, resulting in 40% loss of disc height. Both HDC gel groups, cellular and acellular, had significant retention of disc height and NP voxel count over the course of five weeks. Average NP voxel counts of cellular gels were higher than those of acellular gels at all time points and statistical significance was achieved at 1 week. Only the cellular group restored NP hydration relative to that of the adjacent healthy control. Further histological assessments indicate that while HDC gels influence the sealing of the defect, the addition of cells generates abundant tissue growth and extracellular matrices at the site of the annular defect, accelerating the reparative process. Disruption of endplate was observed in the puncture group, but not in the treated segments. Conclusion In vivo studies on the cell-based annular repair are few in number. Our preliminary findings suggest that fibrochondrocytes can potentially improve HDC gel-based annular repair. A long term study with sufficient sample size are necessary to confirm these results. References Bruske-Hohlfeld I, Merritt JL, Onofrio BM, et al. Incidence of lumbar disc surgery. A population-based study in Olmsted County, Minnesota, 1950-1979. Spine 1990;15(1):31–35 Carragee EJ, Han MY, Suen PW, Kim D. Clinical outcomes after lumbar discectomy for sciatica: the effects of fragment type and anular competence. J Bone Joint Surg Am 2003;85-A(1):102–108 Laus M, Bertoni F, Bacchini P, Alfonso C, Giunti A. Recurrent lumbar disc herniation: what recurs? (A morphological study of recurrent disc herniation). Chir Organi Mov 1993;78(3):147–154 Barth M, Weiss C, Thomé C. Two-year outcome after lumbar microdiscectomy versus microscopic sequestrectomy: part 1: evaluation of clinical outcome. Spine 2008;33(3):265–272 O'Connell GD, Malhotra NR, Vresilovic EJ, Elliott DM. The effect of nucleotomy and the dependence of degeneration of human intervertebral disc strain in axial compression. Spine 2011;36(21):1765–1771 Frei H, Oxland TR, Rathonyi GC, Nolte LP. The effect of nucleotomy on lumbar spine mechanics in compression and shear loading. Spine 2001;26(19):2080–2089 DePalma MJ, Ketchum JM, Saullo TR, Laplante BL. Is the history of a surgical discectomy related to the source of chronic low back pain? Pain Physician 2012;15(1):E53–E58 Grunert P, Borde BH, Hudson KD, Macielak MR, Bonassar LJ, Härtl R. Annular repair using high-density collagen gel: a rat-tail in vivo model. Spine 2014;39(3):198–206 Borde B, Grunert P, Härtl R, Bonassar LJ. Injectable, high-density collagen gels for annulus fibrosus repair: An in vitro rat tail model. J Biomed Mater Res A 2015;103(8):2571–2581 Grunert P, Hudson KD, Macielak MR, et al. Assessment of intervertebral disc degeneration based on quantitative magnetic resonance imaging analysis: an in vivo study. Spine 2014;39(6):E369–E378 Grunert P, Borde BH, Towne SB, et al. Riboflavin crosslinked high-density collagen gel for the repair of annular defects in intervertebral discs: An in vivo study. Acta Biomater 2015;26:215–224

Functional Outcomes of Microdiscectomy- Does Obesity affect Early Postoperative Outcomes?

Introduction Lumbar Disc pathology remains one of the leading causes of back pain with a multitude of surgical options. Choosing the best management option remains a challenge for many practitioners due to the individualized needs and variables of each patient. Obesity poses a challenge to surgeons regarding anesthesia, positioning and adequate exposure which required longer incisions. Studies showed that in selected patient population, microdiscectomy achieved favorable short and long term outcomes with most patients achieving a good to excellent recovery on Macnab Classification up to 10 years post operatively. Studies also showed that obesity was not associated with increased risk of herniated nucleus pulposus after microdiscectomy, However, increased BMI was associated with significantly increased estimated blood loss (EBL) and operative time without affecting the surgical outcomes such as length of hospital stay, recurrent disc herniation, and intra-operative durotomy. Methods Study subjects were identified through the microdiscectomy registry at Hamad Medical Corporation. 50 patients who had microdiscectomy over one year prior to the closure of the study were enrolled. The study population was divided into two groups according to their BMI. Group A had BMI less than 25 kg/m2while group B included those with a BMI equal to and above 25 kg/m2. Patients' medical records were reviewed for demographics, complications and radiographic findings. Patients were interviewed and Short Form 12 (SF-12) and Visual Analogue Scale (VAS) scores were obtained and compared with their preoperative counterparts. Results Statistical analysis showed no significant differences in SF-12 or VAS scores between the 2 groups at one year follow up. Conclusion In the early post operative period, quality of life and pain following microdiscectomy is not affected by the patient's BMI.

Reoperation Rates following Single-Level Discectomy

Introduction Lumbar discectomy is the most commonly performed procedure for treatment of radiculopathy due to lumbar disc herniation. Randomized trials have demonstrated the advantage of surgical removal of herniated disc material over non-surgical treatment options, allowing for a more rapid reduction in symptoms and return of function. Many small-size studies suggest that long-term outcomes for patients treated with discectomy and non-operative management are similar. Additionally, treatment of recurrent lumbar disc herniation is not standardized. Population-level data regarding reoperation following single level hemilaminotomy and discectomy is limited. Material and Methods Data was collected and analyzed for 13,654 patients undergoing single-level lumbar discectomy between January 2007 and December 2010 using the commercially available PearlDiver software (PearlDiver, Inc., Fort Wayne, IN, USA). The nationwide Humana private insurance database was queried for patients billed with the Current Procedural Terminology (CPT) code for our index procedure, hemilaminotomy and removal of disc material (CPT-63030). Patients receiving concurrent lumbar surgeries were excluded from the index group. The index group was then followed in retrospective cohorts for 3 months, 6 months, 1 year, 2 years, and 4 years for recurrent lumbar surgery, including spinal fusion, laminectomy, and additional discectomy. Results Patients received additional lumbar surgeries following single-level discectomy at a rate of 3.95% (539/13654) within 3 months and 12.2% (766/6274) within 4 years of the index procedure. Lumbar spinal fusion was performed on 5.90% (370/6274) of patients within 4 years, with interbody fusion in 75.4% (279/370) of cases and multi-level fusion in 47.0% (174/370) of cases. Reoperation for re-exploration discectomy at the same level as the index procedure with no subsequent surgeries occurred in 2.71% (170/6274) of patients followed out to 4 years. Patients who received a re-exploration discectomy at the same intervertebral level within 2 years of the index procedure went on to receive lumbar fusion at a rate of 38.4% (48/125) within the 4 years following the re-exploration discectomy. Conclusion Data in our study demonstrated a reoperation rate of 12.2% after single level discectomy, a routinely performed procedure for the treatment of symptomatic lumbar disk herniation. Moreover, we show that the rate of progression to lumbar fusion after a re-exploration discectomy was 38.4% within 4 years of reoperation. These data should help surgeons in their operative decision-making and counseling recommendations to patients. To our knowledge, this is the largest population study delineating reoperation rates across the US after single-level lumbar discectomy. Further studies are needed regarding the best treatment algorithm in patients with re-herniation or iatrogenic instability following lumbar discectomy.

PEEK Rods for Posterior Lumbar Fixation: Pros and Cons: The First French Series

Introduction The ideal lumbar spine fixation system should provide sufficient stability while preserving natural posturing and spinal alignment with limited risk of adjacent level degeneration. While rigid fixation systems may contribute to stress shielding in anterior column increasing consecutively adjacent segment degeneration, Polyetherethrketone (PEEK) Rods provide a modulus of elasticity close to cancellous bone that may decrease these risks. Biomechanical studies comparing rigid fixation using titanium Rods with PEEK Rods posterior systems have shown a comparable intervertebral stability with the two systems nevertheless PEEK was associated with a lower risk of screw mobilization in poor bone, an increased anterior physiological load and a reduced stress on bone-screw interface that may predict lower risk of adjacent level degeneration. We performed a retrospective study in a french cohort of patients who underwent posterior lumbar fixation using PEEK Rods to investigate clinical indications and clinical outcomes in real life settings. Material and Methods Between June 2011 and July 2014, 48 patients who underwent posterior lumbar fixation using PEEK Rods were included in our study for retrospective review. Surgery was performed using 5,5mm pre-bent PEEK Rods with Titanium monoaxial screws for 1 to 4 level posterior lumbar fixation with a maximum length of 160 mm. Clinical outcomes were assessed using Oswestry Disability Index (ODI), reoperation rate, complications, radiographs and MRI. The patients satisfaction was also evaluated using the Patient Satisfaction Index (PSI). Results The population included 28 males and 20 females with an average age of 61 years. The main indication for surgery was spinal decompression with stabilization (44,6%). A majority of patients (29/60,4%) presented surgical antecedents including recurrent disc herniation, posterior decompression, posterior fusion with instrumentation and stabilization with interspinous devices. Patients underwent surgery on one (18/37,5%) or multiple levels (30/62,5%). Patients had surgery with anterior cages for fusion (PLIF), posterior dynamic fixation or hybrid systems combining fusion and non-fusion. The most frequent surgeries were performed on L4L5S1 as hybrid systems. At 2 years follow-up, the mean ODI score was improved by 29% (from 67% to 38%) and the mean PSI was 1,8 on a scale ranging from 1 to 4 (1: completely satisfied. 4: same or worse condition than before surgery). There was no reoperation for 89,7% patients, no migration for 94,7%, no screw breakage for 84,2% (never for one single level fixation) and no rod breakage. We reported 15% patients with post-operative adjacent level degeneration. For 21% patients with pre-operative signs, the degeneration was no more observed on the last MRI evaluation after 2 years. Conclusion PEEK Rods provide a safe and effective system that can be either used as a fusion system promoting anterior fusion with decreased risk of implant failure, as dynamic system protecting adjacent levels, or as hybrid system combining both advantages, with a stability comparable to Titanium rods. Further studies on larger populations and longer term follow-up are needed to confirm these data.

Establishment of Endoscopic Spinal Neurosurgery and its Current Status

Percutaneous endoscopic lumbar discectomy(PELD)has been used as a standard surgical technique for lumbar disc herniation at the Southern TOHOKU Healthcare Group since its introduction in 2009. We present our clinical experiences with PELD for 6 years and discuss the decision-making process for its surgical indication with a review of the pertinent literature. PELD can be performed under both local anesthesia and general anesthesia, and requires only a stab wound for surgery and 3 days of hospitalization. Our surgical results showed generally satisfactory outcomes; however, a salvage surgery was required for 10 of the 96 patients(10.4%)because of early recurrence, insufficient removal of the transligamentous disc fragment, and coexistent canal stenosis. Surgery was discontinued because of unbearable intraoperative pain in one patient each undergoing transforaminal approach and extraforaminal approach under local anesthesia. Although our experience is limited, PELD is considered a promising minimally invasive surgery for lumbar disc herniation. It is generally indicated for patients who are young, sports oriented, or extremely busy. Recurrent disc herniation after microdiscectomy, high risk for general anesthesia, and emergency are considered ideal indications for this technique. Since PELD is a newer technique with a high learning curve, further study, continuous training, and education are required before its widespread implementation. Careful selection of patients is crucial to achieve satisfactory surgical results.

Prospective Comparison of Microsurgical, Tubular-Based Endoscopic, and Endoscopically Assisted Diskectomies: Clinical Effectiveness and Complications in Railway Workers

Although endoscopic diskectomy is superior to microsurgical diskectomy in terms of incision size, postoperative pain, and cosmetic appeal, the effectiveness and indications for endoscopic versus microsurgical diskectomy remain active discussion topics. Because of the increasing incidence of diskectomies being performed in Russia, further assessment of these techniques is needed. We performed a comparative analysis of 1-year clinical results and complications of microsurgical, tubular-based interlaminar endoscopic, and endoscopically assisted microsurgical diskectomies for patients with herniated lumbar disks. The patient cohort included 131 patients who were enrolled in a prospective, randomized controlled study and 617 patients for whom data were gathered retrospectively. The quality of life was assessed using the Oswestry Disability Index (version 2.1a) and pain severity was analyzed using the visual analog scale for pain preoperatively, at discharge, and at 3, 6, and 12 months postoperatively. Microsurgical, tubular-based endoscopic, and endoscopically assisted microsurgical diskectomies were all effective in relieving acute radicular symptoms. Recurrent disk herniation occurred more frequently after tubular-based endoscopic diskectomy than after the other approaches. Our findings indicate that these 3 surgical techniques are highly effective and have similar clinical results at 1-year follow-up. Although this study points to differences in complications resulting from the 3 techniques, larger prospective studies are needed to more definitively assess possible surgical differences, complications, and outcomes. The endoscopically assisted diskectomy technique allows for minimally invasive surgery and offers enhanced visualization of the anatomy that is hidden from view in microscopic procedures.