Risk Of Reherniation Research Articles

Shape and Size of the Annulus Fibrosus Excision Alters the Biomechanics of the Intervertebral Disc.

Biomechanical testings and finite element analysis. This study aims to investigate how annulus fibrosus (AF) incision size (RIS, Ratio of incision width to AF height) and shape affect intervertebral disc (IVD) biomechanics. A validated finite element model of lumbar spines simulated various incisions in the middle-right posterior region of the AF, with different sizes and shapes. Simulations included axial compression, flexion, extension, bending, and rotation. Parameters assessed included stability, re-herniation, and IVD degeneration by analyzing stress, height, Intradiscal pressure (IDP), and the range of motion (ROM). Incision increased AF stress and ROM under 3 Nm moment, with values rising as RIS increased. RIS exceeding 40% resulted in a 20% AF stress increase during compression and extension, while RIS over 50% led to over 20% AF stress increase during other motions. Incision stress also increased with higher RIS, particularly surpassing 50% RIS. IDP rose across all incision shapes. Endplate stress increased (9.9%-48.9%) with larger incisions, with average increases of 12.8%, 12.7%, 30.5%, and 22.8% for circular, oval, square, and rectangular incisions. Compression and rotation minimally affected NP pressure (<15%), while flexion (19.8%-38.8%) and bending (18.5%-43.9%) had a more pronounced effect. ROM increased with RIS (20.0% ∼ 77.4%), especially with an incision RIS exceeding 40%. AF injury elevates AF stress, reduces spine stability, heightens degeneration risk with increasing RIS. Reherniation risk rises when RIS exceeds 40%. Circular or oval incisions maintain spine biomechanics better than square or rectangular ones.

Does crural repair with biosynthetic mesh improve outcomes of revisional surgery for recurrent hiatal hernia?

BackgroundLaparoscopic revisional surgery for recurrent hiatal hernia (HH) is technically demanding. Re-recurrences are common and esophageal hiatus mesh reinforcement might improve durability of the repair, thus minimizing the risk of re-herniation.PurposeAssess safety and effectiveness of simple suture repair (no mesh group) vs. crural augmentation with a biosynthetic absorbable mesh (mesh group) in patients with recurrent HH.MethodsObservational retrospective study from September 2012 to December 2022. Only patients undergoing redo surgery for previous failures of hiatal hernia repair were enrolled. Surgical failure was defined as symptomatic recurrent HH with > 2 cm of gastric tissue above the diaphragmatic impression at upper gastrointestinal endoscopy and/or swallow study. Gastro-Esophageal Reflux Disease Health-Related Quality of Life (GERD-HRQL) and Short Form-36 (SF-36) questionnaires were used to assess and preoperative and postoperative symptoms and quality of life.ResultsOne hundred four patients were included. Overall, 60 patients (57.7%) underwent mesh-reinforced cruroplasty, whereas 44 (42.3%) underwent simple suture cruroplasty. Mesh and no mesh groups had similar baseline demographics, symptoms, prevalence of esophagitis and Barrett’s esophagus, and HH size. A composite crural repair was most commonly performed in the mesh group (38.3% vs. 20.5%; p = 0.07). In addition to cruroplasty, most patients (91%) underwent a Toupet fundoplication. The 90-day postoperative complication rate was 8.6%, and there was no mortality. Recurrent HH was diagnosed in 21 patients (20.2%) with a clinical trend toward reduced incidence in the mesh group (16.7% vs. 25%; p = 0.06). Compared to baseline, there was a statistically significant improvement of median GERD-HRQL score (p < 0.01) and all SF-36 items (p < 0.01).ConclusionsLaparoscopic revisional surgery for recurrent HH is safe and effective. Selective use of biosynthetic mesh may protect from early recurrence and has the potential to reduce re-herniation in the long-term.

Machine learning predictive model for lumbar disc reherniation following microsurgical discectomy

IntroductionThe integration of machine learning (ML) algorithms into the field of neurosurgery has the potential to facilitate the decision-making process for the surgeons, improve the surgical outcomes and the overall patient satisfaction rates. Reoperations for same level lumbar disc reherniation are associated with poorer outcomes and greater rate of complications. Research questionProper preoperative patient evaluation could reveal the individuals at higher risk of reherniation. A novel machine learning algorithm was used for the creation of a predictive scoring system for lumbar disc reherniation for patients requiring microdiscectomy without fusion. Material and methodsRetrospective chart review was completed of all adult patients that underwent microdiscectomy without fusion for symptomatic single level LDH, in a single center, over the last 3 years. 230 patients met the inclusion criteria. 19 of them required a second surgical intervention due to same level reherniation. ResultsUtilizing the Risk-SLIM model, the Lumbar Reherniation Score (LRS) was created. The score's accuracy was tested against other model architectures, and a standard five-fold cross-validation was performed. The LRS has AUC of 0.87, confusion matrix accuracy of 0.74, Matthews correlation coefficient of 0.36 and informedness of 0.62. The LRS individual reherniation risk probability ranges from 0% to 88.1%. Discussion and conclusionThe LRS is a novel, easy-to-use, patient-specific tool for preoperative prediction of the individual patient-specific risk of same level symptomatic reherniation following microdiscectomy. Further validation and testing of the model is needed before it can be used in real-life patient treatment.

P-146 A SYSTEMATIC REVIEW OF IMAGING MARKERS FOR HIATUS HERNIA OUTCOMES

Abstract Hiatus hernia repair is a common operation with considerable variation in anatomy and technique. At present there are very few predictors of post-operative outcomes. Certain imaging characteristics may help in operative planning and predicting outcomes. The aim of this systematic review is to identify possible radiological markers associated with clinical outcomes in hiatal hernia repair. A literature search was performed on the 7th December 2021 in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis Of Observational Studies in Epidemiology guidelines of the PubMed, EMBASE and Cochrane Central Register of Controlled Trials using the following search term: ((hiatus) OR (paraesophageal)) AND (hernia) AND ((computed tomography) OR (CT) OR (imaging) OR (contrast) OR (swallow) OR (magnetic resonance) OR (ultrasound)). Inclusion criteria were studies (any design) testing the association of a radiological marker with any clinical outcome (either operative or non-operative) of hiatus hernia management. Exclusion criteria were case reports, non-English articles, non-human articles. Articles were screened by 2/3 authors on the basis of title and abstract. Full text articles were then retrieved for detailed analysis. Any disagreement was resolved by consultation with a 3rd/4th author. Initial search identified 2768 papers, 9 of which were retrieved for full paper evaluation. Preliminary review of the literature suggests that hernia recurrence is correlated with increased hernia size, although patients tend to be asymptomatic. Multidimensional CT can accurately measure hernia surface area and this could be useful in stratifying risk of re-herniation.

P-138 PREDICTORS OF COMPLICATIONS IN COMPLEX VENTRAL HERNIA REPAIR USING POSTERIOR COMPONENT SEPARATION TECHNIQUE WITH RETRO RECTUS MESH PLACEMENT – AN OBSERVATIONAL STUDY

Abstract Introduction Incisional Hernia has an incidence ranging from 2–20%. Large and complex incisional hernias are difficult to treat with standard procedures. PCS-TAR is a relatively novel procedure. There persists a gap in knowledge regarding its outcomes, especially in the Indian population. Aims &amp; Objective To identify the pre-operative clinical and radiological factors that predict the risk of re-herniation and wound and mesh-related complications after CVH (Complex Ventral Hernia) Methodology In a prospective observational study, patients undergoing open PCS-TAR with retro rectus mesh for Complex Ventral Hernia repair included in the study. The patient demographics, hernia characteristics, radiological details, operative data, post- operative outcomes, and follow-up data were entered in a pre-designed proforma. Data were analyzed with SPSS softwere. Results 35 patients with CVH were included, of which 30 (85%) women and 5 men. The mean age was 51.8 years and the mean BMI was 29.7 kg/m2. The mean size of defect was 12 cm. 83% hernia were midline primary and 255 were recurrent hernias. We observed zero recurrences at six months of follow-up, but a high wound morbidity rate of up to 49%, of which most common was seroma formation. 23% of patients developed SSI. Conclusion In conclusion, PCS-TAR is a promising novel procedure for complex ventral hernias not amenable to primary closure using the traditional retro rectus approach, with excellent short term outcomes. Wound morbidity is a significant concern with this procedure, which can be prevented or reduced by thorough pre-operative optimization on a case-to-case basis.

A biomechanical testing method to assess tissue adhesives for annulus closure

Intervertebral disc (IVD) degeneration has been linked to Low Back Pain (LBP) which affects over 80% of the population ranking first in terms of disability worldwide. Degeneration progresses with age and is often accompanied by annulus fibrosus (AF) tearing and nucleus pulposus (NP) herniation. Existing therapies fail to restore IVD function and may worsen AF defects, increasing the risk of reherniation in nearly 30% of patients. Current AF closure options are ineffective, presenting biological or mechanical limitations. Bioadhesives have potential use in this area, however methods to assess performance are limited. Herein, we propose a biomechanical testing method to assess bioadhesives’ capacity to seal AF tears.Two candidate bioadhesives to seal AF tears were evaluated; a tough hydrogel adhesive, and a cyanoacrylate-based glue. The adhesion energy at the interface between bovine discs and the tough hydrogel adhesive was quantified using a peel test (n=4). An experimental method to measure the burst pressure of IVDs was then developed. This method was used to quantify the burst pressure of intact (n=7), injured (AF punctured with a 21G needle; n=7), and sealed IVDs (after applying either the tough hydrogel adhesive patch as a sealant; n=5, or the cyanoacrylate-based glue over the AF tear; n=6).The tough adhesive yielded a strong adhesion energy of 239 ± 49 J/m2 during the peel tests. A maximum pressure of 13.2 ± 3.8 MPa was observed for intact discs in the burst pressure tests, which reduced by 61.4% to 5.1 ± 1.5 MPa in the injured IVDs (p < 0.01)). Application of a cyanoacrylate-based glue to injured IVDs did not recover the burst pressure with statistical significance, however, application of the tough adhesive to injured IVDs, restored burst pressure to 12.3 ± 4.5 MPa, which was not significantly different to the intact burst pressures.In this study, a simple biomechanical method to assess the performance of bioadhesives to seal AF tears based upon burst pressure has been established. Using this method it was found that a tough hydrogel adhesive was able to seal an AF injury, such that the IVD burst pressures were similar to those measured in intact specimens. This method can be used to provide a biomechanical assessment of bioadhesives under high magnitude loading and can complement existing cyclic testing methods that are currently used to assess AF closure devices, improving their assessment before clinical use.

Lumbar Discectomy With Barricaid Device Implantation in Patients at High Risk of Reherniation: Initial Results From a Postmarket Study.

BackgroundPatients with large defects in the annulus fibrosus following lumbar discectomy have high rates of symptomatic reherniation and reoperation. An FDA randomized controlled trial (RCT) with a bone-anchored device (Barricaid, Intrinsic Therapeutics, Woburn, MA) that occludes the annular defect reported significantly lower risk of symptomatic reherniation and reoperation compared to patients receiving discectomy only. However, results of the Barricaid device in real-world use remain limited. MethodsThis was a post-market study to determine the real-world outcomes of the Barricaid device when used in addition to primary lumbar discectomy in patients with large annular defects. Main outcomes included leg pain severity, Oswestry Disability Index (ODI), adverse events, symptomatic reherniation, and reoperation. Imaging studies were read by an independent imaging core laboratory. This paper reports the initial three-month primary endpoint results from the trial; one-year patient follow-up is ongoing.ResultsAmong 55 patients (mean age 41±13 years, 60% male), the mean percent reduction in leg pain severity was 92%, and the mean percent reduction in ODI score was 79%. The three-month rate of symptomatic reherniation was 3.6% and the rate of reoperation was 1.8%. The serious adverse event rate was 5.5%; no device migrations or fractures were observed. ConclusionAmong patients with large annular defects following lumbar discectomy treated with the Barricaid device in real-world conditions, early results demonstrated clinically meaningful improvements in patient symptoms and low rates of symptomatic reherniation, reoperation, and complications, which were comparable to those observed with the device in an FDA-regulated trial.

A challenging playing field: Identifying the endogenous impediments to annulus fibrosus repair.

Intervertebral disc (IVD) herniations, caused by annulus fibrosus (AF) tears that enable disc tissue extrusion beyond the disc space, are very prevalent, especially among adults in the third to fifth decade of life. Symptomatic herniations, in which the extruded tissue compresses surrounding nerves, are characterized by back pain, numbness, and tingling and can cause extreme physical disability. Patients whose symptoms persist after nonoperative intervention may undergo surgical removal of the herniated tissue via microdiscectomy surgery. The AF, however, which has a poor endogenous healing ability, is left unrepaired increasing the risk for re‐herniation and pre‐disposing the IVD to degenerative disc disease. The lack of understanding of the mechanisms involved in native AF repair limits the design of repair systems that overcome the impediments to successful AF restoration. Moreover, the complexity of the AF structure and the challenging anatomy of the repair environment represents a significant challenge for the design of new repair devices. While progress has been made towards the development of an effective AF repair technique, these methods have yet to demonstrate long‐term repair and recovery of IVD biomechanics. In this review, the limitations of endogenous AF healing are discussed and key cellular events and factors involved are highlighted to identify potential therapeutic targets that can be integrated into AF repair methods. Clinical repair strategies and their limitations are described to further guide the design of repair approaches that effectively restore native tissue structure and function.

Analysis of the influence of species, intervertebral disc height and Pfirrmann classification on failure load of an injured disc using a novel disc herniation model

Background ContextAnnular repair devices offer a solution to recurrent disc herniations by closing an annular defect and lowering the risk of reherniation. Given the significant risk of neurologic injury from device failure it is imperative that a reliable preclinical model exists to demonstrate a high load to failure for the disc repair devices. PurposeTo establish a preclinical model for disc herniation and demonstrate how changes in species, intervertebral disc height and Pfirrmann classification impacts failure load on an injured disc. We hypothesized that: (1) The force required for disc herniation would be variable across disc morphologies and species, and (2) for human discs the force to herniation would inversely correlate with the degree of disc degeneration. Study designAnimal and human cadaveric biomechanical model of disc herniation. MethodsWe tested calf lumbar spines, bovine tail segments and human lumbar spines. We first divided individual lumbar or tail segments to include the vertebral bodies and disc. We then hydrated the specimens by placing them in a saline bath overnight. A magnetic resonance images were acquired from human specimens and a Pfirrmann classification was made. A stab incision measuring 25% of the diameter of the disc was then done to each specimen along the posterior intervertebral disc space. Each specimen was placed in custom test fixtures on a servo-hydraulic test frame (MTS, Eden Prarie, MN) such that the superior body was attached to a 10,000 lb load cell and the inferior body was supported on the piston. A compressive ramping load was placed on the specimen in load control at 4 MPa/sec stopping at 75% of the disc height. Load was recorded throughout the test and failure load calculated. Once the test was completed each specimen was sliced through the center of the disc and photos were taken of the cut surface. ResultsFifteen each of calf, human, and bovine tail segments were tested. The failure load varied significantly between specimens (p<.001) with human specimens having the highest average failure load (8154±2049 N). Disc height was higher for lumbar/bovine tail segments as compared to calf specimens (p<.001) with bovine tails having the highest disc height (7.1±1.7 mm). Similarly, human lumbar discs had a cross sectional area that was greater than both bovine tail/calf lumbar spines (p<.001). There was no correlation between disc height and failure load within each individual species (p>.05). Cross sectional area and failure load did not correlate with failure load for human lumbar spine and bovine tails (p>.05) but did correlate with calf spine (r=0.53, p=.04). There was a statistically significant inverse correlation between disc height and Pfirrmann classification for human lumbar spines (r=−0.84, p<.001). There was also a statistically significant inverse relationship between Pfirrmann classification and failure load (r=−0.58, p=.02). ConclusionsWe have established a model for disc herniation and have shown how results of this model vary between species, disc morphology, and Pfirrmann classification. Both hypotheses were accepted: The force required for disc herniation was variable across species, and the force to herniation for human spines was inversely correlated with the degree of disc degeneration. We recommend that models using human intervertebral discs should include data on Pfirrmann classification, while biomechanical models using calf spines should report cross sectional area. Failure loads do not vary based on dimensions for bovine tails. Clinical SignificanceOur analysis of models for disc herniation will allow for quicker, reliable comparisons of failure forces required to induce a disc herniation. Future work with these models may facilitate rapid testing of devices to repair a torn/ruptured annulus.

Putting the Pieces in Place: Mobilizing Cellular Players to Improve Annulus Fibrosus Repair.

The intervertebral disc (IVD) is an integral load-bearing tissue that derives its function from its composite structure and extracellular matrix composition. IVD herniations involve the failure of the annulus fibrosus (AF) and the extrusion of the nucleus pulposus beyond the disc boundary. Disc herniations can impinge the neural elements and cause debilitating pain and loss of function, posing a significant burden on individual patients and society as a whole. Patients with persistent symptoms may require surgery; however, surgical intervention fails to repair the ruptured AF and is associated with the risk for reherniation and further disc degeneration. Given the limitations of AF endogenous repair, many attempts have been made toward the development of effective repair approaches that reestablish IVD function. These methods, however, fail to recapitulate the composition and organization of the native AF, ultimately resulting in inferior tissue mechanics and function over time and high rates of reherniation. Harnessing the cellular function of cells (endogenous or exogenous) at the repair site through the provision of cell-instructive cues could enhance AF tissue regeneration and, ultimately, improve healing outcomes. In this study, we review the diverse approaches that have been developed for AF repair and emphasize the potential for mobilizing the appropriate cellular players at the site of injury to improve AF healing. Impact statement Conventional treatments for intervertebral disc herniation fail to repair the annulus fibrosus (AF), increasing the risk for recurrent herniation. The lack of repair devices in the market has spurred the development of regenerative approaches, yet most of these rely on a scarce endogenous cell population to repair large injuries, resulting in inadequate regeneration. This review identifies current and developing strategies for AF repair and highlights the potential for harnessing cellular function to improve AF regeneration. Ideal cell sources, differentiation strategies, and delivery methods are discussed to guide the design of repair systems that leverage specialized cells to achieve superior outcomes.

2. The reherniation after decompression (RAD) score identifies patients at low risk for reherniation after lumbar decompression surgery

BACKGROUND CONTEXT Herniations of lumbar intervertebral discs are one of the most common injuries sustained across the United States, and present challenges in management for the spine surgeon. Though patients often experience symptomatic relief following surgical decompression, reherniation is a common, yet unpredictable occurrence that may lead to further adverse outcomes. PURPOSE The purpose of this study was to create a prognostic tool to identify patients at greatest risk for reherniation after surgery. STUDY DESIGN/SETTING Retrospective cohort study. PATIENT SAMPLE Patients were identified by reviewing magnetic resonance imaging (MRI) studies and clinical documentation to identify all patients receiving surgical decompression of the lumbar spine for a herniated nucleus pulposus (HNP) from 2006 to 2018. OUTCOME MEASURES Reherniation of a lumbar intervertebral disc after decompression surgery. METHODS Following identification of the eligible cohort, patient charts were subsequently queried for type, location and incidence of reherniation events after decompression surgery. Baseline demographic (age, sex, body mass index (BMI), American Society of Anesthesiologist (ASA) Class, smoking history), clinical (duration of symptoms, type of herniation, number of planned operative levels), and radiographic information (pelvic tilt (PT), pelvic incidence (PI), sacral slope (SS), coronal angulation (CA), lumbar lordosis (LL)) was also collected. Following an 80:20 training and testing data split, multiple imputation and LASSO logistic regression were employed to build and validate a predictive model to identify patients at risk for reherniations after surgery. Ten folds of cross-validation were used to identify tuning parameters for the LASSO logistic regression model, allowing for selection of the strongest predictors for reherniation events. This model was subsequently refit to the multiply-imputed data to allow calculation of pooled model estimates. A threshold to distinguish patients as low- or high-risk for reherniations was established using Youden's index. The threshold for statistical significance was set p RESULTS A total of 517 patients (318 male, 199 female) presented for surgical decompression of a lumbar HNP, in which 51 experienced reherniations after surgery. Patients had a mean age of 45.2±13.9 years, BMI of 29.4±6.3 kg/m2, and 22.4±28.0 months of follow-up. Most herniations were paracentral (431/517; 83.4%), followed by central (55/517; 10.6%), and far lateral (29/517; 5.6%). Reherniations were seen at a mean of 46.0±70.0 months after surgery. LASSO logistic regression identified nine significant predictors for reherniations: age, sex, ASA class, operative levels, duration of preoperative symptoms, paracentral disc herniation, preoperative PI, preoperative LL, and VAS-Leg scores. Paracentral disc herniations and duration of preoperative symptoms were the strongest positive and negative predictors for reherniation outcomes, respectively. Validation of this model demonstrated excellent model discrimination (AUC: 0.834), sensitivity (71.4%), and specificity (87.6%). Within the testing cohort, 16.3% and 83.7% of patients were identified as high- and low-risk, respectively. Of these, 29.4% of high-risk patients (5/17) sustained future reherniations, while nearly all low-risk patients (85/87; 98.7%) experienced no recurrence of their HNP. CONCLUSIONS This is the first study to develop and validate a screening tool to identify patients with clear differences in risk for reherniation after lumbar decompression for HNP. With further validation, this tool can be readily implemented in clinical practice, and may accurately identify patients likely to experience lasting surgical benefit for lumbar disc herniations. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Could the Splitting of the Annulus During Percutaneous Endoscopic Lumbar Diskectomy (PELD) Be a Culprit for Recurrent Disk Herniation?: An Analysis of the Reherniation Pattern After PELD

To explore which preoperative radiologic variables have propensity for reherniation and to evaluate whether the inherent annulus splitting procedure during percutaneous endoscopic lumbar diskectomy (PELD) could prompt reherniation, we assessed the correlation between the anatomic location of annular penetration and reherniation. Three hundred and fifty patients who underwent PELD for central or subarticular disk herniation through a transforaminal approach were followed-up for at least 24 months. Fifty-four subjects that were reoperated for recurrent herniation were allocated as the reherniation group and the other 296 subjects were allocated as the non-reherniation group. The numerical rating scale score, another lumbosacral disk herniation (LDH) lesion in addition to the PELD level (another LDH), location (central or subarticular) and severity of LDH (protrusion or extrusion), and tear of the posterior longitudinal ligament (PLL) were compared between the 2 groups to identify which variables could be predictive factors for reherniation. To assess the influences of PELD on reherniation, location and severity of reherniation were compared with those of initial herniation. The location at the subarticular region and the existence of a concomitant PLL tear during initial LDH were significantly related to subsequent reherniation. The location and severity of these reherniations were significantly retained when compared with those of primary herniation. PLL tear and subarticular herniation were significantly related to recurrent disk herniation. Reherniation patterns after PELD generally matched those of primary herniation. The annulus penetrating step during PELD did not increase the risk of reherniation.

Two-year real-world results of lumbar discectomy with bone-anchored annular closure in patients at high risk of reherniation

To determine the safety and effectiveness of limited lumbar discectomy with additional implantation of an annular closure device (ACD) among patients at high risk of herniation recurrence treated in routine clinical practice. This was a prospective, single-center study of lumbar discectomy for sciatica caused by intervertebral disc herniation with adjunctive ACD implantation to reduce herniation recurrence risk among high-risk patients with large annular defects. Patients returned for follow-up visits at 6weeks, 12weeks, 26weeks, 1year, and 2years. Main outcomes included reoperation, herniation recurrence, back pain severity, leg pain severity, and Oswestry Disability Index (ODI). The minimum important difference was defined as ≥ 20mm decrease relative to baseline for leg pain severity, ≥ 20mm decrease for back pain severity, and ≥ 15-point decrease for ODI. Among 75 high-risk patients (mean age 45years, 59% female), the cumulative event incidence through 2years was 4.0% for reoperation and 1.4% for herniation recurrence. Mean leg pain severity decreased from 73 to 6 (p < 0.001), back pain severity decreased from 51 to 13 (p < 0.001), and ODI decreased from 49 to 7 (p < 0.001). The percentage of patients achieving the minimum important difference was 91% for leg pain, 65% for back pain, and 94% for ODI. In patients at high risk of herniation recurrence following limited lumbar discectomy in routine clinical practice, additional implantation of an ACD was safe and reherniation recurrence rates were low at 2-year follow-up, which is favorably compared to reported rates in high-risk patients.

Clinical performance of a bone-anchored annular closure device in older adults.

Background: Lumbar discectomy is a common surgical procedure in middle-aged adults. However, outcomes of lumbar discectomy among older adults are unclear.Methods: Lumbar discectomy patients with an annular defect ≥6 mm width were randomized to receive additional implantation with a bone-anchored annular closure device (ACD, n=272) or no additional implantation (controls, n=278). Over 3 years follow-up, main outcomes were symptomatic reherniation, reoperation, and the percentage of patients who achieved the minimum clinically important difference (MCID) without a reoperation for leg pain, Oswestry Disability Index (ODI), SF-36 Physical Component Summary (PCS) score, and SF-36 Mental Component Summary (MCS) score. Results were compared between older (≥60 years) and younger (<60 years) patients. We additionally analyzed data from two postmarket ACD registries to determine consistency of outcomes between the randomized trial and postmarket, real-world results.Results: Among all patients, older patients suffered from crippling or bed-bound preoperative disability more frequently than younger patients (57.9% vs 39.1%, p=0.03). Among controls, female sex, higher preoperative ODI, and current smoking status, but not age, were associated with greater risk of reherniation and reoperation. Compared to controls, the ACD group had lower risk of symptomatic reherniation (HR=0.45, p<0.001) and reoperation (HR=0.54, p=0.008), with risk reductions comparable in older vs younger patients. The percentage of patients achieving the MCID without a reoperation was higher in the ACD group for leg pain (81% vs 72%, p=0.04), ODI (82% vs 73%, p=0.03), PCS (85% vs 75%, p=0.01), and MCS (59% vs 46%, p=0.007), and this benefit was comparable in older versus younger patients. Comparable benefits in older patients were observed in the postmarket ACD registries.Conclusion: Outcomes with lumbar discectomy and additional bone-anchored ACD are superior to lumbar discectomy alone. Older patients derived similar benefits with additional bone-anchored ACD implantation as younger patients.

Three-year results from a randomized trial of lumbar discectomy with annulus fibrosus occlusion in patients at high risk for reherniation

BackgroundA larger defect in the annulus fibrosus following lumbar discectomy is a well-known risk factor for reherniation. Procedures intended to prevent reherniation by sealing or occluding the annular defect warrant study in high-risk patients. This study sought to determine 3-year results of lumbar discectomy with a bone-anchored annular closure device (ACD) or lumbar discectomy only (controls) in patients at high risk for reherniation.MethodsThis multicenter randomized trial enrolled patients with sciatica due to lumbar intervertebral disc herniation who failed conservative treatment. Patients with large annular defects after lumbar limited microdiscectomy were intraoperatively randomly assigned to receive ACD or control. Clinical and imaging follow-up was performed at routine intervals over 3 years. Main outcomes included rate of reherniations, reoperations, and endplate changes; leg and back pain scores on a visual analogue scale; Oswestry Disability Index (ODI); Physical Component Summary (PCS) and Mental Component Summary (MCS) scores from the SF-36; and adverse events adjudicated by a data safety monitoring board.ResultsAmong 554 randomized patients, the modified intent-to-treat population consisted of 272 patients in which ACD implantation was attempted and 278 receiving control; device implantation was not attempted in 4 patients assigned to ACD. Outcomes at 3 years favored ACD for symptomatic reherniation (14.8% vs. 29.5%; P < 0.001), reoperation (11.0% vs. 19.3%; P = 0.007), leg pain (21 vs. 30; P < 0.01), back pain (23 vs. 30; P = 0.01), ODI (18 vs. 23; P = 0.02), PCS (47 vs. 44; P < 0.01), and MCS (52 vs. 49; P < 0.01). The frequency of all-cause serious adverse events was comparable between groups (42.3% vs. 44.5%; P = 0.61).ConclusionsThe addition of a bone-anchored ACD in patients with large annular defects following lumbar discectomy reduces the risk of reherniation and reoperation, and has a similar safety profile over 3-year follow-up compared with lumbar limited discectomy only.Trial registrationClinicalTrials.gov NCT01283438

Comparison of treatments for lumbar disc herniation: Systematic review with network meta-analysis.

Systematic review with network meta-analysis. To compare patient outcomes of lumbar discectomy with bone-anchored annular closure (LD + AC), lumbar discectomy (LD), and continuing conservative care (CC) for treatment of lumbar disc herniation refractory to initial conservative management. Several treatment options are available to patients with refractory symptoms of lumbar disc herniation, but their comparative efficacy is unclear. A systematic review was performed to compare efficacy of LD + AC, LD, and CC for treatment of lumbar disc herniation. Outcomes included leg pain, back pain, disability (each reported on a 0-100 scale), reherniation, and reoperation. Data were analyzed using random effects network meta-analysis. This review included 14 comparative studies (8 randomized) involving 3947 patients-11 studies of LD versus CC (3232 patients), 3 studies of LD + AC versus LD (715 patients), and no studies of LD + AC versus CC. LD was more effective than CC in reducing leg pain (mean difference [MD] -10, P < .001) and back pain (MD -7, P < .001). LD + AC was more effective than LD in reducing risk of reherniation (odds ratio 0.38, P < .001) and reoperation (odds ratio 0.33, P < .001). There was indirect evidence that LD + AC was more effective than CC in reducing leg pain (MD -25, P = .003), back pain (MD -20, P = .02), and disability (MD -13, P = .02) although the treatment effect was smaller in randomized trials. Results of a network meta-analysis show LD is more effective than CC in alleviating symptoms of lumbar disc herniation refractory to initial conservative management. Further, LD + AC lowers risk of reherniation and reoperation versus LD and may improve patient symptoms more than CC.

Reduction of direct costs in high-risk lumbar discectomy patients during the 90-day post-operative period through annular closure.

PurposeDespite being an extremely successful procedure, recurrent disc herniation is one of the most common post-discectomy complications in the lumbar spine and contributes significant health care and socioeconomic costs. Patients with large annular defects are at a high risk for reherniation, but an annular closure device (ACD) has been designed to reduce reherniation risk in this population and may, in turn, help control direct health care costs after discectomy.Patients and methodsThis analysis examined the 90-day post-discectomy cost estimates among ACD-treated (n=272) and control (discectomy alone; n=278) patients in a randomized controlled trial (RCT). Direct medical costs were estimated based on 2017 Humana and Medicare claims. Index discectomies were assumed to occur in an outpatient (OP) setting, whereas repeat discectomies were assumed to be 60% in OP and 40% in inpatient (IP). A sensitivity analysis was performed on this assumption. The device cost was not included in the analysis in order to focus on costs in the 90-day post-operative period.ResultsWithin 90 days of follow-up, post-operative complications occurred in 3.3% of the ACD patients and 8.6% of the control patients (P=0.01). The average 90-day cost to treat an ACD patient was $10,257 compared to $11,299 per control patient for a 80:20 distribution of Commercial:Medicare coverage ($1,042 difference). This difference varied from $687 with 100% Medicare to $1,132 with 100% Commercial coverage. Varying the IP vs OP distribution resulted in a cost difference range of $968 to $1,156 with the ACD.ConclusionAugmenting discectomy with an ACD in high-risk patients with a large annular defect reduced reherniation and reoperation rates, which translated to a reduction of direct health care costs between $687 and $1,156 per patient during the 90-day post-operative period. Large annular defect patients are an easily identifiable high-risk population. Operative strategies that reduce complication risks in these patients, such as the ACD, could be advantageous from both patient care and economic perspectives.

Prevention of lumbar reherniation by the intraoperative use of a radiofrequency bipolar device: A case-control study.

Objective:The most common complication after lumbar discectomy is reherniation. Although many studies have investigated factors that may increase the reherniation risk, few are agreed upon all. It has been suggested that limited nucleus removal is associated with higher reherniation risk, while more aggressive nucleus removal can result in increased disc degeneration. Here, we assessed the efficacy of a coblation-assisted microdiscectomy in adult patients undergoing single-level disc surgery.Methods:We prospectively compared the reherniation rate in 75 patients (Group 1) undergoing single-level lumbar disc surgery completed with the radiofrequency bipolar system Aquamantys® (Medtronic, Minneapolis, MN, USA) to that of a historical control group (n = 75) matched for variables related to herniation level and characteristics (Group 2). Patients were followed up to 4 years. Reherniations were assessed, pain and function were monitored throughout, and imaging was performed at annual follow-up.Results:The overall symptomatic reherniation rate was 4%. In particular, one case (1.3%) was observed in Group 1 and five (6.7%) in Group 2 (P < 0.05). Magnetic resonance imaging identified a total of 4 (2.7%) asymptomatic reherniations at 12 months, 6 (4%) at 24 and 36 months, and 7 (4.7%) at 48 months. Overall, Group 1 contained one (1.3%) asymptomatic reherniation case, while six (8%) were observed in Group 2 (P < 0.05).Conclusions:The low reherniation rate in patients treated by the coblation-assisted microdiscectomy suggests that this technique may reduce the reherniation risk. Clinical outcomes for pain and function at 4 years follow-up compared favorably with literature data. Randomized controlled trial could confirm these results.

Patients at the Highest Risk for Reherniation Following Lumbar Discectomy in a Multicenter Randomized Controlled Trial.

Background:The purposes of the present study were to (1) confirm the risk of recurrent lumbar disc herniation in patients with a large anular defect who had undergone limited discectomy and (2) assess potential risk factors within this population.Methods:The patient population was extracted from the control cohort of a prospective, randomized, multicenter controlled trial investigating the efficacy of an anular closure device following standard limited discectomy. All control patients underwent limited discectomy for the treatment of a single-level symptomatic posterior or posterolateral lumbar disc herniation. Only patients presenting with a large anular defect (6 to 10 mm wide by 4 to 6 mm long) were included in the study (n = 278). Baseline demographic, clinical, and surgical characteristics were recorded. Follow-up evaluations were performed at 6 weeks and at 3, 6, 12, and 24 months. Imaging modalities included magnetic resonance imaging, low-dose computed tomography, and radiographs. Symptomatic recurrent lumbar disc herniation was defined as any symptomatic postoperative herniation on either side of the index level. A multivariate logistic regression analysis of demographic and surgical variables associated with the incidence of recurrent lumbar disc herniation was performed.Results:The mean anular defect area (and standard deviation) was 39.3 ± 9.1 mm2, and the mean excised nuclear tissue volume was 1.3 ± 0.8 mL. At 2 years, the incidence of symptomatic recurrent lumbar disc herniation was 25.3% (64 of 253), with the herniation occurring at a mean of 264 days after the index procedure. Of the 64 patients with recurrent lumbar disc herniation, 36 underwent a subsequent surgical procedure. Logistic regression analysis identified an increased risk for recurrent lumbar disc herniation in females (odds ratio, 2.2) and in patients with greater anular defect widths (odds ratio, 1.3). Furthermore, multivariate logistic regression analyses revealed a significant interaction between age and sex (p = 0.005).Conclusions:The outcomes of the present study provide the most substantial evidence to date in confirming previous reports of a high risk of reherniation among patients with large anular defects. Among those with large anular defects (width, ≥6 mm), females ≤50 years of age had the highest risk (up to ∼10 times higher) of recurrent lumbar disc herniation. It is recommended that an anular repair or closure should be performed after limited discectomies in patients with large anular defects.Level of Evidence:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Post-lumbar discectomy reoperations that are associated with poor clinical and socioeconomic outcomes can be reduced through use of a novel annular closure device: results from a 2-year randomized controlled trial

IntroductionLumbar discectomy patients with large annular defects are at a high risk for reherniation and reoperation, which could be mitigated through the use of an annular closure device (ACD). To identify the most effective treatment pathways for this high-risk population, it is critical to understand the clinical outcomes and socioeconomic costs among reoperated patients as well as the utility of ACD for minimizing reoperation risk.MethodsThis was a post hoc analysis of a prospective, multicenter, randomized controlled trial (RCT) designed to investigate the safety and efficacy of an ACD. All 550 patients (both ACD treated and control) from the RCT with follow-up data through 2 years were included in this analysis (69 reoperated and 481 non-reoperated). Reoperations were defined as any revision surgery of the index level, regardless of indication. Equivalent U.S. Medicare expenditures for reoperations were estimated through cost multipliers derived from the commercially available PearlDiver database.ResultsA significantly greater number of control patients (45/278; 16%) compared to ACD patients (24/272; 9%) underwent a revision surgery at the index level within 2 years of followup (p=0.01). At 2 years of follow-up, the reoperated patients had significantly worse Oswestry Disability Index scores and visual analog scale for leg and back pain scores compared to their non-reoperated counterparts (p<0.0001). The total estimated direct medical costs for reoperation were US $952,348 ($13,802 per reoperated patient), with control patients accounting for the majority of this cost burden ($565,188; 59%).ConclusionPost-discectomy reoperation is associated with significantly increased patient morbidity, missed work, and direct treatment costs in a population at high risk for reherniation. Annular closure helped minimize this clinical and socioeconomic burden by reducing the incidence of reoperation by nearly 50% (16% control vs 9% ACD).