Location Of Herniation Research Articles

Hand Posture Inversion Effect: Inverted and Individual Identification Paradigm

Blowout fractures are common in midfacial trauma and often involve other parts of facial bones. Sometimes, patients have complications caused by inadequate management. Surgical indications, such as clinical symptoms, can be inaccurate owing to post-traumatic swelling or hematoma formation. Previous studies on the prediction of enophthalmos used the orbital volume ratio (OVR) or only the volume of herniated tissue. This study examined which of these values is more predictive of the degree of enophthalmos. In addition, the predictive values for a 2-mm enophthalmos in unoperated blowout fractures were assessed.A total of 191 patients underwent nonoperative treatment for blowout fractures at our institution; they were divided into 2 groups according to the degree of enophthalmos (>2 mm vs 0 to 2 mm) and were further divided into 3 subgroups according to the location of the fracture (inferior, medial, or inferomedial). Multifactor logistic regression analysis was performed to determine the relationship between the degree of enophthalmos and these values.We observed a correlation between the OVR and the degree of enophthalmos, as well as a correlation between the volume of herniated tissue and the degree of enophthalmos. Regarding the anatomic location of herniation, the orbital floor was found to be more correlated with the amount of enophthalmos.The OVR is a more reliable predictor than measurement of the volume of herniated tissue. The relationship found between radiologic examination findings and the degree of enophthalmos can be used as a surgical indication in addition to consideration of the anatomic location.

MRI predictors of revision surgery after primary lumbar discectomy

The prognostic significance of preoperative MRI findings in patients undergoing discectomy is incompletely understood. Identifying the radiological predictors of revision surgery on pre-operative MRI can guide management decisions and potentially prevent multiple surgeries. We included 181 patients who underwent primary lumbar discectomy between 2010 and 2014. All patients were contacted via a short telephone interview to determine if they had revision surgery within 5 years of their index surgery. Preoperative MRI of the lumbosacral spine was evaluated for various radiological factors including type of disc herniation, anatomical location of herniation, direction of herniation, degree of disc degeneration, end plate changes and presence of listhesis. Other potential confounders including age, gender, smoking status and index level of surgery were also recorded. Multivariate model of all radiological predictors and confounders were developed and a step-wise approach was used to remove insignificant variables in order to develop final significant multivariate model. P value of <0.05 was considered statistically significant. Patients with retrolisthesis were found to be 2.7 times more likely than the patients without listhesis to require revision surgery (p = 0.019). Patients with foraminal disc herniation were 3.45 times more likely than the patients with paramedian disc herniation to require revision surgery (p = 0.026). Other MRI predictors failed to achieve statistical significance. Based on the data presented patients with retrolisthesis and/or foraminal disc herniation should be counselled on the relatively higher risk of revision surgery when proceeding with discectomy, or alternative options should be considered.

Does the Size or Location of Lumbar Disc Herniation Predict the Need for Operative Treatment?

Study Design:Retrospective cohort study.Objective:The goal of this study was to determine whether the absolute size (mm2), relative size (% canal compromise), or location of a single-level, lumbar disc herniation (LDH) on axial and sagittal cuts of magnetic resonance imaging (MRI) were predictive of eventual surgical intervention.Methods:MRIs of 89 patients were reviewed, and patients were split into groups based on type of management received (34 nonoperative vs 55 microdiscectomy). Radiographic characteristics—including size of disc herniation (mm2), size of spinal canal (mm2), location of herniation on axial (central, paracentral, foraminal) and sagittal (disc level, suprapedicle, pedicle, infrapedicle) planes, and type of herniation (bulge, protrusion, extrusion, sequestration)—were measured by 2 independent, orthopedic spine fellows and compared between groups via univariate and multivariate analyses.Results:The operative group showed a significantly higher percentage of canal compromise (39.5% vs 31.1%, P = .001) compared to the nonoperative group. Multiple logistic regression analysis showed higher odds of eventual operative intervention for a disc protrusion (odds ratio [OR] 6.30 [1.99, 19.86], P = .002) or disc extrusion (OR 11.5 [1.63, 81.2], P = .014) for Rater 1 and a higher odds of eventual surgical management for a paracentral location for both Rater 1 and Rater 2 (OR = 3.39 [1.25, 9.22], P = .017, and OR = 5.46 [1.77, 16.8], P = .003, respectively).Conclusions:Disc herniations in a paracentral location were more likely to undergo operative treatment than those more centrally located, on axial MRI views.

Does Size Matter? An Analysis of the Effect of Lumbar Disc Herniation Size on the Success of Nonoperative Treatment.

Study Design:Retrospective study.Objective:In this study, we examined whether the size of a lumbar disc herniation (LDH) is predictive of the need for surgical intervention within 2 years after obtaining an initial magnetic resonance imaging (MRI) scan. We hypothesized that a fragment that occupied a larger percentage of the spinal canal would not predict which patients failed conservative management.Methods:Using the ICD-10 code M51.26, we identified patients at a single academic institution, across the 2-year period from 2015 to 2016, who received a diagnosis of primary lumbar radicular pain, had MRI showing a disc herniation, and underwent at least 6 weeks of nonoperative management. Patients experiencing symptoms suggesting cauda equina syndrome and those with progressive motor neurological deficits were excluded from analysis, as were patients exhibiting “hard” disc herniations. Within the axial view of an MRI, the following measurements were made on AGFA-IMPACS for a given disc herniation: the length of both the canal and the herniated disc along the anterior-posterior axis, the average width of the disc within the canal; the total canal area, and the area of the disc herniation. Data analysis was conducted in SPSS and a 2-tailed reliability analysis using Cronbach’s alpha as a measure of reliability was obtained.Results:A total of 368 patients met the inclusion and exclusion criteria for this study. Of these, 14 (3.8%) had L3-L4 herniations, 185 had L4-L5 herniations (50.3%), and 169 had L5-S1 herniations (45.9%). Overall, 336 (91.3%) patients did not undergo surgery within 1 year of the LDH diagnosis. Patients who did not receive surgery had an average herniation size that occupied 31.2% of the canal, whereas patients who received surgery had disc herniations that occupied 31.5% of the canal on average. A Cronbach’s alpha of .992 was observed overall across interobserver measurements. After controlling for age, race, gender, and location of herniation through a logistic regression, it was found that the size of the herniation and the percentage of the canal that was occupied had no predictive value with regard to failure of conservative management, generating an odds ratio for surgery of 1.00.Conclusions:The percentage of the spinal canal occupied by a herniated disc does not predict which patients will fail nonoperative treatment and require surgery within 2 years after undergoing a lumbar spine MRI scan.

A Review of Minimally Invasive Surgical Techniques for the Management of Thoracic Disc Herniations.

Thoracic disc herniation (TDH) is a rare, but technically challenging, disorder. Apart from their unfamiliarity with this condition, surgeons are often posed with challenges regarding the diverse methods available to address TDH, the neurological disturbances accompanying the disorder, the prospect of iatrogenic cord damage during surgical procedures, and the complications associated with various surgical approaches. In today’s era, when minimally invasive surgery has been incorporated into almost every aspect of managing spine disorders, it is necessary for surgeons to be aware of the various minimally invasive techniques available for the management of these rare and difficult conditions. In this review article, we provide a synopsis of the epidemiology, clinical features, and technical aspects of TDH, starting from level identification to intraoperative neuromonitoring and including important steps and guidance for all the minimally invasive approaches to TDH. We conclude the review by providing insights into the clinical decision-making process and outline the specific aspects of “giant” thoracic discs and indications for fusion in certain conditions. Outcomes of minimally invasive surgery for these conditions are generally favorable. The location of herniation is an important factor for surgical planning.

Percutaneous Endoscopic Spine Surgery for Extruded Lumbar Disc Herniation

The conventional open discectomy is the gold standard for treating extruded lumbar disc herniation, especially in highly migrated lumbar disc herniation. Endoscopic spine surgery is known to be very challenging and technically demanding, in particular for highly migrated disc herniation. However, several studies have reported numerous effective techniques with results approximatively equal to conventional open surgeries or mini-open surgery. In the last few years, an increased number of endoscopic spine surgical techniques have been proposed in order to overcome various issues encountered in traditional endoscopic spine surgery. Nevertheless, surgical approach selection for treating extruded lumbar disc herniation is based on aspects such as anatomical structures, availability of surgical instruments, surgeon’s experience, and the disc herniation location. Advances in endoscopic visualization and instrumentation, as well as an increased demand for minimally invasive procedures, have led to the popularity of Percutaneous Endoscopic Lumbar Discectomy (PELD). PELD is a recent and advanced technique among other minimally invasive spine surgeries (MIS). It includes various kinds of surgical techniques to treat lumbar disc herniation and aims to offer a safe, less invasive surgical procedure for lumbar disc space decompression and removal of nucleus pulposus.

3-Dimensional Volumetric Analysis of Relationship Between the Orbital Volume Ratio and Enophthalmos in Unoperated Blowout Fractures

Blowout fractures are common in midfacial trauma and often involve other parts of facial bones. Sometimes, patients have complications caused by inadequate management. Surgical indications, such as clinical symptoms, can be inaccurate owing to post-traumatic swelling or hematoma formation. Previous studies on the prediction of enophthalmos used the orbital volume ratio (OVR) or only the volume of herniated tissue. This study examined which of these values is more predictive of the degree of enophthalmos. In addition, the predictive values for a 2-mm enophthalmos in unoperated blowout fractures were assessed. A total of 191 patients underwent nonoperative treatment for blowout fractures at our institution; they were divided into 2 groups according to the degree of enophthalmos (>2mm vs 0 to 2mm) and were further divided into 3 subgroups according to the location of the fracture (inferior, medial, or inferomedial). Multifactor logistic regression analysis was performed to determine the relationship between the degree of enophthalmos and these values. We observed a correlation between the OVR and the degree of enophthalmos, as well as a correlation between the volume of herniated tissue and the degree of enophthalmos. Regarding the anatomic location of herniation, the orbital floor was found to be more correlated with the amount of enophthalmos. The OVR is a more reliable predictor than measurement of the volume of herniated tissue. The relationship found between radiologic examination findings and the degree of enophthalmos can be used as a surgical indication in addition to consideration of the anatomic location.

Posterior Percutaneous Endoscopic Cervical Diskectomy: A Single-Center Experience of 252 Cases

Posterior percutaneous endoscopic cervical foraminotomy and diskectomy has remarkably evolved with successful results. Although percutaneous endoscopic cervical diskectomy (PECD) has gained popularity, the risk of surgical failure may be a major obstacle to performing PECD. We analyzed unsuccessful cases requiring reoperation. The objective of this article was to find common causes of surgical failure and elucidate the limitations of the conventional PECD technique. Surgery-related complications were reviewed from the initial 252 cases of a single surgeon. The patients had cervical disk herniation or radiculopathy and underwent percutaneous endoscopic surgical management. We investigated clinical outcomes and complications. A retrospective review was performed on all patients who had undergone PECD between April 2013 and April 2016. Unsuccessful PECD was defined as a case requiring reoperation within 6 weeks after primary surgery. Chart review was done, and pre-, intra-, and postoperative radiographic reviews were performed. All unsuccessful PECD cases were classified according to the type of herniated disc, location of herniation, extruded disk migration, working channel position, and intra- and postoperative findings. The mean operative time was 89.4 minutes (range, 60-180 minutes). The mean intraoperative blood loss was 20.3 mL (range, 10-800 mL). Cerebrospinal fluid leakage occurred in 1 patient and healed well. The follow-up period ranged from 24 to 60 months. The mean score on the visual analog scale improved from 8.67 ± 1.30 preoperatively to 7.83 ± 1.40 at 1 month postoperatively to 1.67±1.30 at the final follow-up (P < 0.05), with a recovery rate of 67.9% ± 21.2%. Surgeons should be aware of the specific complications for the PECD approach.

The Effect of Computer-Assisted Reporting on Interreader Variability of Lumbar Spine MRI Degenerative Findings: Five Readers With 30 Disc Levels

PurposeThe aim of this study was to assess differences in interreader variability among radiologists after the implementation of a computer-assisted reporting (CAR) tool for the interpretation of degenerative disc disease on lumbar spine MRI. MethodsThirty lumbar spine MRI examinations were selected from the radiology database. Five fellowship-trained musculoskeletal radiologists evaluated each L4-L5 disc in a blinded fashion and reported the findings using a traditional free dictation approach. One month later, they reinterpreted the same discs using a web browser–based CAR tool in the same blinded fashion. The degrees of central canal stenosis, neural foraminal stenosis, and facet joint osteoarthritis; presence or absence of lateral recess stenosis; types of disc bulge or herniation; and herniation location using both methods were recorded. Percentage disagreement among the radiologists for each variable was calculated and compared using the Wilcoxon signed rank test. ResultsThere was a statistically significant decrease among the five radiologists in percentage disagreement for neural foraminal stenosis (46% versus 35%, P = .0146) and facet joint osteoarthritis (45% and 22%, P < .0001) for reports created by free dictation compared with those created using the CAR tool. There was no statistically significant difference in interreader variability for the assessment of central canal stenosis, lateral recess effacement, disc herniation, disc bulge, or herniation location. ConclusionsImplementation of a CAR tool for the interpretation of degenerative changes on lumbar spine MRI decreases interreader variability in the assessment of neural foraminal stenosis and facet joint osteoarthritis.

Risk Factors for Recurrent Herniation After Percutaneous Endoscopic Lumbar Discectomy.

Percutaneous endoscopic lumbar discectomy (PELD) has been widely used for treating lumbar disc herniation. Recurrence after PELD has been reported, but few studies have focused on the risk factors responsible for recurrence after PELD. This retrospective study enrolled 116 patients with recurrent herniation after successful PELD from March 2005 to March 2016. Kaplan-Meier method and Cox regression analysis were employed to identify significant risk factors predicting recurrence after PELD. Univariate analysis showed that older age (≥50 years old), obesity (body mass index ≥25), no smoking history, decreased reflexes, learning curve of the surgeon (<200 cases), treatment period (March 2005 to September 2010), Modic change, migrated herniation, and central herniation are potential risk factors for recurrence after PELD. Multivariate analysis suggested that older age (≥50 years old), obesity (body mass index ≥25), learning curve of the surgeon (<200 cases), treatment period (March 2005 to September 2010), and central location of herniation are independent significant risk factors for recurrence after PELD. Obesity (body mass index ≥25) was the most robust risk factor responsible for recurrence after PELD. Older age (≥50 years old), learning curve of the surgeon (<200 cases), treatment period (March 2005 to September 2010), and central location of herniation were also closely associated with recurrent herniation after successful PELD.

Relationship of specific MRI findings to treatment outcomes in patients receiving transforaminal epidural steroid injections

To determine whether specific MRI findings are related to outcomes after lumbar transforaminal epidural steroid injections (TFESI) and to assess the inter-rater reliability of imaging diagnosis. A prospective outcomes study on 156 consecutive patients with 1-month follow-up outcomes data and MRI within 3months of TFESI was conducted. Pain levels (numerical rating scale) (NRS) were recorded prior to injection. Overall 'improvement' was determined using the Patients Global Impression of Change (PGIC) scale and NRS data were collected at three time points post injection. Two radiologists independently evaluated all images blinded to treatment outcome for reliability of diagnosis. The Chi-square test compared MRI findings for the senior radiologist to 'improvement'. NRS change scores were compared to MRI findings with the unpaired t-test or ANOVA. Kappa and percent agreement assessed inter-rater agreement of diagnosis. The only abnormality linked to 'improvement' (p = 0.03) and higher NRS change scores (p = 0.0001) at 1month was the disc herniation morphology 'protrusion + sequestration'. Patients with degeneration by osteophytes (p = 0.034), grade 3 foraminal nerve root compression (p = 0.01) and foraminal/extraforaminal location of herniation (p = 0.014) also had higher 1month NRS change scores. Reliability of diagnosis was 'fair' to 'substantial' depending on MRI findings. Patients with disc protrusion plus sequestration were significantly more likely to report overall improvement and more pain reduction at 1month. Higher pain reduction was noted in patients with degeneration by osteophytes, grade 3 foraminal nerve root compression, or foraminal/extraforaminal disc herniation location.

The Clinical Efficacy for Two-Level Transforaminal Epidural Steroid Injections

BackgroundEpidural steroid injections have been used in combination with other modalities for the treatment of lumbar radicular pain. The literature has shown that 1-level lumbar fluoroscopically guided transforaminal epidural steroid injections (TFESIs) are effective in decreasing pain and morbidity; however, the efficacy of 2-level TFESIs has not been investigated, although they are performed by many practitioners in the treatment of lumbar radicular pain. ObjectivesTo assess the clinical effectiveness of 2-level TFESIs in patients with unilateral, single-level lumbar radicular pain. In addition, a subgroup analysis was performed based on disk herniation location. Study DesignRetrospective cohort. SettingOutpatient physiatry pain practice. PatientsA total of 721 patients were included in this study having undergone a two-level transforaminal epidural steroid injection. MethodsThe study group included patients who underwent a 2-level lumbar TFESI. Patients presented for lumbar radicular pain as the result of disk herniation with or without radiculopathy and were scheduled to receive a lumbar TFESI at L3 or below. Of this group, only those that underwent a 2-level TFESIs were included in the study, and data analysis was carried out on this group. Main Outcome MeasuresSubjects were assessed with a pain numerical rating scale (NRS 0-10) and Oswestry Disability Index (ODI) before TFESI and at 2-week and 2-month follow-up. Responders were defined as greater that 50% reduction in NRS or greater than 40% reduction in ODI. ResultsA total of 57.7% of patients were responders in terms of NRS (P < .05, confidence interval 53.6%-61.9%) and 51.7% responded in ODI at 2-month follow-up (P < .05 [confidence interval 47.5%-55.9%]). In addition, patients with complete pain relief (defined as 0/10 on NRS) were noted at both 2-week (n = 239, 33%) and 2-month (n = 130, 18%) follow-up. In subgroup analysis, the paracentral/subarticular disk group had an increased number of responders, 66.0% in NRS and 64.0% in ODI at 2-month follow-up (P < .05). ConclusionsTwo-level TFESIs are effective in the management of radicular pain, but more research is needed to evaluate the utility of this treatment compared with single-level TFESI. Our study showed a greater improvement in pain and function as a result of 2-level TFESIs in the setting of paracentral/subarticular disk herniations. Level of EvidenceIV

Recurrence of Pain After Usual Nonoperative Care for Symptomatic Lumbar Disk Herniation: Analysis of Data From the Spine Patient Outcomes Research Trial

ObjectiveTo determine risks and predictors of recurrent leg and low back pain (LBP) after unstructured, usual nonoperative care for subacute/chronic symptomatic lumbar disk herniation (LDH). DesignSecondary analysis of data from a concurrent randomized trial and observational cohort study. SettingThirteen outpatient spine practices. ParticipantsA total of 199 participants with resolution of leg pain and 142 participants with resolution of LBP from among 478 participants receiving usual nonoperative care for symptomatic LDH. Assessment of Risk FactorsPotential predictors of recurrence included time to initial symptom resolution, sociodemographics, clinical characteristics, work-related factors, imaging-detected herniation characteristics, and baseline pain bothersomeness. Main Outcome MeasurementsLeg pain and LBP bothersomeness were assessed by the use of a 0-6 numerical scale at up to 4 years of follow-up. For individuals with initial resolution of leg pain, we defined recurrent leg pain as having leg pain, receiving lumbar epidural steroid injections, or undergoing lumbar surgery subsequent to initial leg pain resolution. We calculated cumulative risks of recurrence by using Kaplan-Meier survival plots and examined predictors of recurrence using Cox proportional hazards models. We used similar definitions for LBP recurrence. ResultsOne- and 3-year cumulative recurrence risks were 23% and 51% for leg pain, and 28% and 70% for LBP, respectively. Early leg pain resolution did not predict future leg pain recurrence. Complete leg pain resolution (adjusted hazard ratio [aHR] 0.47, 95% confidence interval [CI] 0.31-0.72) and posterolateral herniation location (aHR 0.61; 95% CI 0.39-0.97) predicted a lower risk of leg pain recurrence, and joint problems (aHR 1.89; 95% CI 1.16-3.05) and smoking (aHR 1.81; 95% CI 1.07-3.05) predicted a greater risk of leg pain recurrence. For participants with complete initial resolution of pain, recurrence risks at 1 and 3 years were 16% and 41% for leg pain and 24% and 59% for LBP, respectively. ConclusionsRecurrence of pain is common after unstructured, usual nonsurgical care for LDH. These risk estimates depend on the specific definitions applied, and the predictors identified require replication in future studies.

Unsuccessful percutaneous endoscopic lumbar discectomy: a single-center experience of 10,228 cases.

Percutaneous endoscopic lumbar discectomy (PELD) has remarkably evolved with successful results. Although PELD has gained popularity for the treatment of herniated disc (HD), the risk of surgical failure may be a major obstacle to performing PELD. We analyzed unsuccessful cases requiring reoperation. To find common causes of surgical failure and elucidate the limitations of the conventional PELD technique. A retrospective review was performed on all patients who had undergone PELD between January 2001 and December 2012. Unsuccessful PELD was defined as a case requiring reoperation within 6 weeks after primary surgery. Chart review was done, and preoperative, intraoperative, and postoperative radiographic reviews were performed. All unsuccessful PELD cases were classified according to the type of HD, location of herniation, extruded disc migration, working channel position, and intraoperative and postoperative findings. In 12 years, 10,228 patients had undergone PELD; 436 (4.3%) cases were unsuccessful. The causes were incomplete removal of HDs in 283 patients (2.8%), recurrence in 78 (0.8%), persistent pain even after complete HD removal in 41 (0.4%), and approach-related pain in 21 (0.2%). Incomplete removal of the HD was caused by inappropriate positioning (95 cases; 33.6%) of the working channel and occurred in central HDs (91 cases; 32.2%), migrated HDs (70 cases; 24.7%), and axillary type HDs (63 cases; 22.3%). Proper surgical indications and good working channel position are important for successful PELD. PELD techniques should be specifically designed to remove the disc fragments in various types of HD.

Clinical and magnetic resonance imaging factors which may predict the need for surgery in lumbar disc herniation.

Study DesignCase-control.PurposeEvaluate clinical and imaging factors which may predict the risk of failure of medical therapy in patients with lumbar disc herniation (LDH).Overview of LiteratureLDH is a common cause of low back pain and radicular leg pain, with a generally favorable natural course. At present, however, it is not possible to identify patients who may be candidates for surgery in an early stage of their disease by means of clinical signs or diagnostic imaging criteria.MethodsWe designed a study investigating patients with untreated low back pain to assess the predictive value of demographic, clinical or imaging findings in identifying patients who finally would meet the classic current criteria for surgery.ResultsAmong 134 patients, 80.6% were successfully treated with conservative therapy and 19.4% finally underwent surgery. Sex, occupation, involved root level, presence of Modic changes, osteophytes or annular tears were not significantly different between the 2 groups, while cerebrospinal fluid block, Pfirrmann's grade, location of herniation with regard to the midline, and type of herniation were significantly different. Anteroposterior fragment size was significantly higher and intervertebral foramen height and thecal sac diameters were significantly lower in the surgical group.ConclusionsAlthough it is strongly recommended to practice conservative management at first for patients with LDH symptoms, the results of this study shows that higher Pfirrmann's grade, more laterally located discs, extrusion and protrusion herniation types, and larger fragments could predict the risk of conservative treatment failure. This way, unnecessarily prolonged conservative management (beyond 4-8 weeks) may be precluded.

Incidence of trocar site herniation following robotic gynecologic surgery

ObjectiveTrocar site herniation is a recognized complication of minimally invasive surgery, but published data on trocar site herniation after robotic surgery are scarce. We sought to determine the incidence of trocar site herniation in women undergoing robotic surgery for gynecologic disease. MethodsA retrospective review of robotic surgeries performed from January 1, 2006, through December 31, 2012, was conducted. Postoperative trocar site herniations were identified, along with time to presentation, location of herniation, and management. Patients were excluded if surgery was converted to laparotomy or traditional laparoscopy. The Wilcoxon rank-sum test was used to compare patients with and without herniation with respect to continuous variables, and Fisher's exact test was used to compare these 2 groups with respect to categorical variables. ResultsThe study included 500 patients, 3 of whom experienced herniation at a single trocar site. The patients with and without herniation did not differ with respect to age, body mass index, smoking status, medical comorbidities, operating time, or estimated blood loss. All 3 herniations occurred at 12-mm trocar sites. Two herniations occurred at assistant port sites, and 1 occurred at the umbilical camera port site. The median time to herniation was 21days (range, 8–38days). One patient required immediate surgical intervention; the other 2 patients had conservative management. ConclusionsTrocar site herniation is a rare complication following robotic surgery. The most important risk factor for trocar site herniation appears to be larger trocar size, as all herniations occurred at 12-mm port sites.

Relevance of the site of assisted hatching in thawed human blastocysts

To the Editor: We read with interest the elegant paper of Miyata et al. (1Miyata H, Matsubayashi H, Fukutomi N, Matsuba J, Koizumi A, Tomiyama T. Relevance of the site of assisted hatching in thawed human blastocysts: a preliminary report. Fertil Steril 2010. DOI:10.1016/j.fertnstert.2010.01.056Google Scholar) in which they reported the existence of polarity in the hatching process of warmed human blastocysts. In detail, artificial zona pellucida (ZP) opening close to the inner cell mass (ICM) resulted in improved rates of complete hatching whereas assisted hatching at the abembryonic site caused trapping of the embryo within the ZP (1Miyata H, Matsubayashi H, Fukutomi N, Matsuba J, Koizumi A, Tomiyama T. Relevance of the site of assisted hatching in thawed human blastocysts: a preliminary report. Fertil Steril 2010. DOI:10.1016/j.fertnstert.2010.01.056Google Scholar). This finding is completely in line with previously published data on the implantation behavior of fresh blastocysts showing different sites of herniation (2Ebner T. Gruber I. Moser M. Location of herniation predicts implantation behaviour of hatching blastocysts.J Turkish-German Gynecol Assoc. 2007; 8: 184-188Google Scholar); however, a significantly higher clinical pregnancy rate (72%) was observed if blastocysts were transferred that hatched close to the ICM as compared with their counterparts that herniated from the mural trophectoderm (51%). This suggests that hatching problems observed during vitrification/warming (1Miyata H, Matsubayashi H, Fukutomi N, Matsuba J, Koizumi A, Tomiyama T. Relevance of the site of assisted hatching in thawed human blastocysts: a preliminary report. Fertil Steril 2010. DOI:10.1016/j.fertnstert.2010.01.056Google Scholar) may be overcome in fresh blastocyst culture. Spontaneous hatching of the human blastocyst in vitro is supported by the increase of internal pressure caused by a gradual accumulation of blastocoelic fluid and cellular (mostly trophectodermal) proliferation. Additional mechanical help to open the outer shell comes from sphincter-like zona-breaker cells (3Sathananthan H. Menezes J. Gunasheela S. Mechanisms of human blastocyst hatching in vitro.Reprod Biomed Online. 2003; 7: 228-234Abstract Full Text PDF PubMed Scopus (66) Google Scholar) and sequences of repeated collapses and re-expansions (“blastocyst breathing”). It is likely that in vitrified and warmed blastocysts the complete opening of the ZP by means of laser pulses (1, Fig. 1A, B) changes the pressure conditions that would be one of the prerequisites for optimal hatching. If the function of zona-breaker cells also is negatively affected by manipulation of the ZP, the hatching process per se cannot be actively completed and, theoretically, in a more passive mode must follow physical rules such as the Hagen-Poiseuille equation (1Miyata H, Matsubayashi H, Fukutomi N, Matsuba J, Koizumi A, Tomiyama T. Relevance of the site of assisted hatching in thawed human blastocysts: a preliminary report. Fertil Steril 2010. DOI:10.1016/j.fertnstert.2010.01.056Google Scholar). Thus, a blastocyst hatching close to the ICM, a location corresponding to the area that later drives invasion into the endometrium, has accelerated contact with the endometrium, which could result in a developmental advantage irrespective of whether it is fresh or cryopreserved. Relevance of the site of assisted hatching in thawed human blastocysts: a preliminary reportFertility and SterilityVol. 94Issue 6PreviewPreliminary data from a prospective randomized study of assisted hatching (AH) of thawed human blastocysts demonstrated that the rate of complete hatching was significantly higher for AH performed near the inner cell mass (ICM) than for AH at the side opposite to the ICM. This suggests the existence of polarity in the hatching process in human blastocysts, which requires further evaluation. Full-Text PDF Reply of the Authors: Relevance of the site of assisted hatching in thawed human blastocystsFertility and SterilityVol. 94Issue 4PreviewWe would like to express our thanks to Ebner et al. for their interest in our paper on the existence of polarity in the hatching process of thawed human blastocysts (1). Full-Text PDF

Brown-Sequard syndrome revealing intradural thoracic disc herniation

Brown-Sequard syndrome (BSS) is a rare form of severe myelopathy characterised by a clinical picture reflecting hemisection of the spinal cord. This syndrome is mostly due to a penetrating injury to the spine but many other non-traumatic causes have been described. Intradural thoracic disc herniation (TDH) is one of the rare aetiologies of this syndrome. Despite progress in imaging techniques, diagnosis and treatment remain difficult. We retrospectively reviewed one of the largest reported series of six patients with BSS revealing intradural TDH between 2003 and 2007. There was a marked female predominance and the mean age was 44 years. Before surgery, half of the patients had a severe neurological deficit. The mean duration of symptoms until surgery was 8.5 months (range 0.5-24 months). Spine magnetic resonance imaging (MRI) or spine computer tomography scan showed calcified TDH between T5-T6 and T9-T10. The intradural location of the thoracic herniation was strongly suspected from the clinical data. All the patients underwent posterolateral transpedicular surgery with an operative microscope to open the dura mater. The intradural location of the herniation was overlooked in one case and the patient underwent a second procedure. The dura mater was carefully closed. Two patients' condition worsened immediately after the surgery before slowly improving. All the other patients improved their neurological status immediately after the surgery and at 12 months follow-up. BSS with TDH on the spine MRI scan may be a warning symptom of the intradural location of the herniated disc. In such cases, spine surgeons are advised to use an operative magnification and to open the dura mater to avoid missing this potentially curable cause of severe myelopathy.

SPORT Lumbar Intervertebral Disk Herniation and Back Pain

Diskectomy candidates with at least 6 weeks of sciatica and confirmatory imaging were enrolled in a randomized or observational cohort. This study sought to determine: (1) whether diskectomy resulted in greater improvement in back pain than nonoperative treatment, and (2) whether herniation location and morphology affected back pain outcomes. Previous studies have reported that lumbar diskectomy is less successful for relief of back pain than leg pain and patients with central disc herniations or protrusions have worse outcomes. Patients underwent diskectomy or received "usual" nonoperative care. Data from the randomized cohort and observational cohort were combined in an as-treated analysis. Low back pain was recorded on a 0 to 6 point scale, and changes in low back pain were compared between the surgical and nonoperative treatment groups. The effects of herniation location and morphology on back pain outcomes were determined. The combined analysis included 1191 patients with 775 undergoing surgery within 2 years, whereas 416 remained nonoperative. Overall, leg pain improved more than back pain in both treatment groups. Back pain improved in both surgical and nonoperative patients, but surgical patients improved significantly more (treatment effect favoring surgery -0.9 at 3 months, -0.5 at 2 years, P < 0.001). Patients who underwent surgery were more likely to report no back pain than nonoperative patients at each follow-up period (28.0% vs. 12.0% at 3 months, P < 0.001, 25.5% vs. 17.6% at 2 years, P = 0.009). At baseline, central herniations were associated with more severe back pain than more lateral herniations (4.3 vs. 3.9, P = 0.012). Patients with central herniations and protrusionshad a beneficial treatment effect from surgery similar to the overall surgical group. Diskectomy resulted in greater improvement in back pain than nonoperative treatment, and this difference was maintained at 2 years for all herniation locations and morphologies.

Percent spinal canal compromise on MRI utilized for predicting the need for surgical treatment in single-level lumbar intervertebral disc herniation

Background context There is limited information describing the correlation between the initial quantitative measurements on magnetic resonance imaging (MRI) scans of disc herniation area, canal cross-section areas, percent canal compromise, and disc herniation location to the need for surgery. Purpose Our aim is to determine if the size of disc herniation area, canal cross-section area, percent canal compromise, and disc herniation location taken from MRI images of patients with symptomatic single-level lumbar herniated intervertebral discs upon initial presentation to a spine surgeon, were predictive of the need for surgical treatment. Study design/setting This is a retrospective case matched study of patient MRI images in the senior author's private practice. Patient sample From a pool of 332 patients with sciatica caused by lumbar intervertebral disc herniations at our institution, 65 patients had surgery, of which MRI images were available and analyzed on 44 patients. Forty-four additional patients were randomly selected from the remaining 267 original group as nonoperative controls. Methods The axial MRI image showing the largest canal compromise by the herniated disc was selected for measurements. Using T1- and T2-weighted images, the areas of interest were digitally scanned at high resolution. The canal area and disc herniation area measurement were calculated from the total number of pixels per cross-sectional area, multiplied by a scan correction factor, mm 2 /pixel. Disc herniation locations were classified into either central or paracentral. The percent canal compromise was obtained by disc herniation area divided by canal cross-section area and multiplied by 100. Results The surgical group's overall mean herniated disc area was 219.6 square millimeter (mm 2), 179.8 at L4-5, and 267.4 at L5-S1. The nonoperative group's overall mean herniated disc area was 178.4 mm 2, 135.1 at L2-3, 160.3 at L4-5, and 207.4 at L5-S1. The surgical group's overall mean canal cross-sectional area was 471.8 mm 2, 418.6 at L4-5, and 535.6 at L5-S1. The nonoperative group's overall mean canal cross-sectional area was 541.3 mm 2, 518.1 at L2-3, 446.8 at L4-5, and 669.9 at L5-S1. The overall percent canal compromise ratio in the surgery group was 46.7%, 44.1% at L4-5, and 49.8% at L5-S1. The overall percent canal compromise in the nonoperative group was 34.2%, 34.1% at L2-3, 36.1% at L4-5, and 31.8% at L5-S1. The percent canal compromise in central herniations at L4-5 level was 53.0% in the surgical group, and 32.8% in the nonoperative group; at the L5-S1 level surgical group percent canal compromise was 64.1% and in the nonoperative group canal compromise was 27%. L4-L5 level paracentral herniations canal compromise was 36.7% in the surgical group compared with 42.5% canal compromise in the nonoperative group. At the L5-S1 level the canal compromise was 45% in the surgical group and 34.8% in the nonoperative group. Conclusions Our findings show a trend for patients treated with surgery to have larger disc herniation areas and smaller canal cross-section areas, corresponding to larger percent canal compromise than the nonoperative group. Centrally located herniations followed this trend closely at all levels studied. However, the paracentral herniation at the L4-5 level does not follow this trend, possibly because paracentral disc herniation clinical course is determined more by herniation location rather than the overall herniation size.