Direct Repair of Symptomatic Lumbar Spondylolysis Using Rod-Screw-Cable System

OBJECTIVE

To assess the efficacy of a new direct lysis repair technique using internal fixation with rod, screws, and Songer cable in symptomatic lumbar spondylolysis.

METHODS

Between December 2015 and January 2020, patients who were diagnosed with symptomatic lumbar spondylolysis and surgically treated with a rod-screw-cable system were recruited. Pedicle screwing by the Magerl technique was performed in all included patients, followed by direct lysis repair with bone allograft and demineralized bone matrix by stabilizing the posterior lamina and spinous process using a rod-screw-cable system. Clinical outcome was measured using the visual analog scale and Oswestry disability index preoperatively and 6 weeks, 3 months, 6 months, 1 year, and 2 years postoperatively.

RESULTS

Sixteen patients were included in this study-11 men and 5 women (mean age: 47 years; range, 26-67 years). The lytic defects were at L4 and L5 in 6 and 10 patients, respectively. The mean follow-up period was 41 months (24-62 months). The visual analog scale values were 7.3, 6.1, 4.3, 3.3, 2.1, and 1.9 preoperatively and 6 weeks, 3 months, 6 months, 1 year, and 2 years postoperatively, respectively. The Oswestry disability index values were 59.8%, 55.4%, 41.7%, 32.4%, 21.1%, and 16.9% for the same periods, respectively. No patient had an increase in the slip after surgery. There were no significant complications such as implant failure.

CONCLUSIONS

Our technique provides rigid intra-segmental repair of spondylolysis without intersegmental motion interference, even if the patient is older or has disc degeneration.

Clinical efficacy of nucleoplasty for uncontained lumbar disc herniation: a retrospective study

BACKGROUND

There are insufficient in-depth studies on whether percutaneous lumbar nucleoplasty (PLN) is effective and safe for the treatment of uncontained lumbar disc herniation (ULDH). This study aimed to investigate the clinical efficacy of PLN on radiating leg pain caused by ULDH.

METHODS

Patients who underwent PLN for ULDH and met the inclusion criteria between June 2018 and July 2022 were included. Clinical outcomes were evaluated using the numeric rating scale (NRS) for radiating pain preoperatively; at 1 day, 1 week, and 1 month postoperatively; and at the last follow-up. Patient satisfaction was assessed using MacNab criteria.

RESULTS

Forty-one patients were enrolled. The mean age was 50.2 years (range 24-73 years). The mean and standard deviation of the preoperative NRS in 39 patients with radiating pain was 9.0 ± 1.2. The NRS scores at 1 day, 1 week, and 1 month postoperatively and at the last follow-up were 4.6 ± 3.2, 3.6 ± 3.3, 2.9 ± 3.2, and 1.4 ± 2.0, respectively, showing significant improvement (all, p < 0.001). The number of patients (percentage) with excellent or good satisfaction according to the MacNab criteria was 29 (70.7%). Major complications were not observed. Three patients underwent additional surgery after PLN because of persistent radiating pain.

CONCLUSIONS

PLN is a safe and feasible treatment option for ULDH. Treatment outcomes were favorable on average; however, the lack of consistency was a drawback.

Traumatic Anterior Cervical Disc Herniation Presenting as Severe Dysphagia

Due to the anatomical characteristics of the cervical spine, few cases of traumatic anterior cervical disc herniation have been reported in the literature. Here, we present a rare case of a traumatic anterior cervical disc herniation presenting as severe dysphagia. A 75-year-old male patient presented with severe dysphagia following an accident three days prior when he fell from a height of stairs. Cervical magnetic resonance (MR) imaging revealed a 1.3 × 1.0 cm extruded disc in the anterior aspect of the C4 level with the base at the C3-4 disc, which displaced the esophagus anteriorly. Esophagography revealed an extrinsic esophageal lesion that was considered to be responsible for the obstruction of the airway at the same level. He underwent a ruptured disc removal via the anterior approach. Preoperative dysphagia was resolved gradually after surgery, and he remained asymptomatic six months after surgery.

Fusion Assessment of Oblique Lumbar Interbody Fusion Using Demineralized Bone Matrix: A 2-Year Prospective Study

OBJECTIVE

Although several studies have reported successful fusion rates after oblique lumbar interbody fusion (OLIF) using allografts or dimerized bone matrix (DBM) instead of autografts, whether OLIF can achieve satisfactory solid fusion without the use of autografts remains unclear. This study investigated the real fusion rates after OLIF using allografts and DBM, which were evaluated using both dynamic radiographs and computed tomography scans.

METHODS

We enrolled 79 consecutive patients who underwent minimally invasive OLIF followed by percutaneous pedicle screw fixation. All patients were treated with OLIF between L2 and L5 and underwent radiographic and clinical follow-ups at 12, 18, and 24 months after surgery. Radiographic assessment of fusion was performed using the modified BrantigaSteffee-Fraser (mBSF) scale, which was categorized as follows: grades I (radiographic pseudoarthrosis), II (indeterminate fusion), and III (solid radiographic fusion). Other radiologic and clinical outcomes were evaluated using the following parameters: vertebral slippage distance, disc height, subsidence, Oswestry Disability Index (ODI), and visual analogue scale (VAS).

RESULTS

Clinical outcomes demonstrated significant improvements in the VAS scores for back pain, leg pain, and ODI after surgery. Subsidence was present in 34 cases (35.4%) at 12 months postoperatively, which increased to 47.9% and reached 50.0% at 1.5 years and 2 years after surgery, respectively. The solid fusion rate after OLIF was 32.3% at 1 year, increased to 58.3% at 1.5 years, and reached 72.9% at 2 years. Radiographic pseudoarthrosis was 24.0% at 1 year, which decreased to 6.3% at 1.5 years and 3.1% at 2 years.

CONCLUSION

OLIF is a safe and effective surgical procedure for the treatment of degenerative lumbar diseases. The mBSF scale, which simultaneously evaluates both dynamic angles and bone bridge formation, offers great reliability for the radiological assessment of fusion. Moreover, OLIF using allografts and DBM, which is performed on one or 2 levels at L2-5, can achieve satisfactory fusion rates within 2 years after surgery.

Search for Evidence of Baryogenesis and Dark Matter in B^{+}→ψ_{D}+p Decays at BABAR

A new dark sector antibaryon, denoted ψ_{D}, could be produced in decays of B mesons. This Letter presents a search for B^{+}→ψ_{D}+p (and the charge conjugate) decays in e^{+}e^{-} annihilations at 10.58 GeV, using data collected in the BABAR experiment. Data corresponding to an integrated luminosity of 398  fb^{-1} are analyzed. No evidence for a signal is observed. Branching fraction upper limits in the range from 10^{-7}-10^{-5} are obtained at 90% confidence level for masses of 1.0 Collapse

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HER2-low expression in patients with advanced or metastatic solid tumors

BACKGROUND

Human epidermal growth factor receptor 2 (HER2)-low is a newly defined category with HER2 1+ or 2+ expression by immunohistochemistry (IHC) and lack of HER2 gene amplification measured by in situ hybridization (ISH). Much remains unknown about the HER2-low status across tumor types and changes in HER2 status between primary and metastatic samples.

PATIENTS AND METHODS

HER2 expression by IHC was evaluated in 4701 patients with solid tumors. We have evaluated the HER2 expression by IHC and amplification by ISH in paired breast and gastric/gastroesophageal (GEJ) primary and metastatic samples. HER2 expression was correlated with ERBB2 genomic alterations evaluated by next-generation sequencing (NGS) in non-breast, non-gastric/GEJ samples.

RESULTS

HER2 expression (HER2 IHC 1-3+) was found in half (49.8%) of the cancers, with HER2-low (1 or 2+) found in many tumor types: 47.1% in breast, 34.6% in gastric/GEJ, 50.0% in salivary gland, 46.9% in lung, 46.5% in endometrial, 46% in urothelial, and 45.5% of gallbladder cancers. The concordance evaluation of HER2 expression between primary and metastatic breast cancer samples showed that HER2 3+ remained unchanged in 87.1% with a strong agreement between primary and metastatic samples, with a weighted kappa (Κ) of 0.85 (95% confidence interval 0.79-0.91). ERBB2 alterations were identified in 117 (7.5%) patients with non-breast, non-gastric/GEJ solid tumors who had NGS testing. Of 1436 patients without ERBB2 alterations, 512 (35.7%) showed any level HER2 expression by IHC.

CONCLUSION

Our results show that HER2-low expression is frequently found across tumor types. These findings suggest that many patients with HER2-low solid tumors might benefit from HER2-targeted therapies.

Complications of Cervical Endoscopic Spinal Surgery: A Systematic Review and Narrative Analysis

BACKGROUND

There are no systematic evidence-based medical data on the complications of endoscopic cervical spinal surgery. This narrative analysis compiled data from various studies that examined endoscopic complications, such as cervical disc herniation and foraminal stenosis. This study aimed to investigate the efficacy and safety of endoscopic surgery in cervical radiculopathy.

METHODS

We searched the PubMed/MEDLINE databases to identify articles on endoscopic spinal surgery, and keywords were set as "endoscopic cervical spinal surgery", "endoscopic cervical discectomy", "endoscopic cervical foraminotomy", and "percutaneous endoscopic cervical discectomy". We analyzed the evidence level and classified the prescribed complications according to the literature. Endoscopic cervical surgery was divided into three categories: full endoscopic anterior, endoscopic posterior, and unilateral biportal approaches. We excluded duplicate publications, studies without full text, studies without complications or incomplete information, and studies that did not provide the necessary data for extraction, animal experiments, or reviews.

RESULTS

Difficulties in swallowing, hematoma, and hoarseness are common complications associated with the anterior cervical approach. In contrast, complications of the posterior approach include nerve root injury, hematoma, and dysesthesia. However, endoscopic cervical spinal surgery, including the full endoscopic anterior, posterior, and unilateral biportal approaches, is a safe and effective treatment for cervical radiculopathy.

CONCLUSIONS

Complications of full endoscopic cervical spinal surgery differ significantly depending on the anterior and posterior approaches. In the anterior approach, swallowing difficulty, recurrent disc, hematoma, and dysphonia are the common complications. In contrast, transient dysesthesia, dural tears, upper limb motor deficits, and persistent arm pain are commonly reported with the posterior approach.

Acute Paraparesis Caused by Spinal Epidural Fluid After Balloon Kyphoplasty for Traumatic Avascular Necrosis: A Case Report

Minimally invasive procedures, such as percutaneous vertebroplasty or balloon kyphoplasty (BK), eliminate motion at the fracture site and relieve pain associated with traumatic avascular necrosis when conservative treatment fails. However, these are associated with complications, most of which are directly related to cement leakage. Herein, we report a rare case of acute paraparesis caused by spinal cord compression by epidural fluid following BK for the treatment of Kummell's disease in the absence of cement leakage. To the best of our knowledge, this is the first report describing this complication.

Massive Epidural Hematoma Caused by Percutaneous Epidural Neuroplasty: A Case Report

Percutaneous epidural neuroplasty (PEN) has been used to manage chronic back pain or radicular pain refractory to other conservative treatments, such as medication, injection, and physical therapy. However, similar to all invasive treatment modalities, it has serious complications, such as dural tears, infections, and hematoma formation. Herein, we present a rare case of an 81-year-old female patient on dementia medication who developed paraplegia 5 days after PEN. This is the first report of a poor outcome in a patient with dementia who developed paraplegia after PEN despite an emergency operation for spinal epidural hematoma.

Open Surgery for Osteoporotic Compression Fracture Within One Month of Single Level Balloon Kyphoplasty

Objective

This study aimed to analyze the reasons for open surgery performed within one month of balloon kyphoplasty (BKP) for osteoporotic compression fractures.

Methods

This study included 15 patients treated with open surgery within one month of BKP in our institution from 2013 to 2020. Among them, 10 patients underwent BKP in our institution and 5 patients were transferred because of adverse events after undergoing BKP at another hospital. Clinical findings including main indications, neurological deficits, and clinical course were analyzed.

Results

All patients were followed up for at least 12 months after surgery (average time 15.5 months, range 12-39 months). Their mean age was 73.7 years and the mean T-score of the spine on bone densitometry was -3.35. The main reasons for open surgery included dislodgement of the cement mass or spinal instability (7 cases, 47%), neural injury due to cement leakage (3 cases, 20%), and spinal cord injury caused by a puncture mistake (3 cases, 20%). Two patients developed acute spinal subdural hematoma, and spinal epidural fluid was pushed out at the back edge of the vertebral body following BKP without signs of major cement leakage into the spinal canal. At the final follow-up, 7 patients with cement mass dislodgement showed complete improvement of related symptoms after posterior fusion with screw fixation. Among the 8 patients with neural injury, 6 improved; however, 2 remained at the same American Spinal Injury Association level.

Conclusion

The main reasons for open surgery were cement mass dislodgement and neural injury caused by puncture errors or cement leakage into the spinal canal. It should be noted that proper selection of cases, detailed imaging evaluation, and optimal surgical techniques are key to reducing open surgery after BKP.

Risk Factors of Restenosis After Full Endoscopic Foraminotomy for Lumbar Foraminal Stenosis: Case-Control Study

OBJECTIVE

To investigate risk factors associated with postoperative restenosis after full endoscopic lumbar foraminotomy (FELF) in patients with lumbar foraminal stenosis (LFS).

METHODS

A single-center, retrospective case-control study was conducted on patients diagnosed with foraminal stenosis who underwent FELF between August 2019 and April 2022. The study included 56 patients, comprising 18 cases and 38 controls. Clinical data, radiologic assessments, and surgical types were compared between the groups. The cutoff values of radiologic parameters that differentiate the 2 groups were investigated.

RESULTS

No significant difference in age, sex distribution, or presence of adjacent segment disease or grade I spondylolisthesis was observed between the groups. Cases had a higher degree of disc wedging angle (DWA) (3.0° ± 1.1° vs. 0.5° ± 1.4°, p < 0.001), larger coronal Cobb angle (CCA) (8.8° ± 5.1° vs. 4.7° ± 2.5°, p = 0.004), and smaller segmental lumbar lordosis (SLL) than controls (11.0 ± 7.4 vs. 18.0 ± 5.4, p = 0.001). Optimal cutoff values for DWA, CCA, and SLL were estimated as 1.8°, 7.9°, and 17.1°, respectively. A significant difference in surgical types was observed between cases and controls (p = 0.004), with the case group having a higher distribution of patients undergoing discectomy in addition to TELF.

CONCLUSION

The study identified potential risk factors for restenosis after FELF in patients with LFS, including higher DWA, larger CCA, smaller SLL angle. We believe that discectomy should be perform with caution during FELF, as it can lead to subsequent restenosis.

Prevalence and methodological quality of systematic reviews in Korean medical journals

This study aimed to assess and evaluate the prevalence and methodological quality of systematic reviews (SRs) published in major Korean medical journals (KMJs). The top 15 journals with the highest Korean Medical Citation Index, published between 2018 to 2021, were selected. We assessed the methodological quality of SRs using A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2). In total, 126 SRs were included, with an average of 32 SRs being reported annually. The overall prevalence of SRs in KMJs was 2.8%, with an increase from 2.6% in 2018 to 3.4% in 2021. Overall, the methodological quality of SRs was low (9.5% low, 90.5% critically low). More than 80% of the studies adhered to critical domain items such as a comprehensive literature search and risk of bias assessment, but for items such as protocol registration and listing excluded studies and the justification for exclusion, the adherence rate was less than 15%. While the number of SRs in KMJs steadily increased, the overall confidence in the methodological quality was low to critically low. Therefore, in order to provide the best evidence for decision-making in clinical and public health areas, editors, reviewers, and authors need to pay more attention to improving the quality of SRs.

Efficacy of Nucleoplasty for Radiculopathy Caused by Foraminal Cervical Disc Herniation: Clinical Results of Case Series and Technical Note

BACKGROUND

Percutaneous cervical nucleoplasty (PCN) is a minimally invasive technique used for the treatment of cervical disc herniation. However, if the lesion is located at the neural foramen, complete access and effective neural decompression are often challenging because of the special anatomical condition of the uncovertebral joint, osteophyte, and facet joint of the cervical foraminal space.

OBJECTIVES

To investigate the effect of PCN on radiculopathy caused by foraminal cervical disc herniation (FCDH).

STUDY DESIGN

Retrospective case series.

SETTING

Single-center tertiary hospital.

METHODS

This study included 44 patients with radiculopathy caused by FCDH who were treated with PCN. Visual analog scale (VAS) scores, preoperative, 1 week, and 3 months postoperatively, and at the last follow-up, as well as the Macnab criteria, were used to evaluate clinical outcomes. A paired t-test was used to compare the preoperative and follow-up VAS scores. The percentage of patients with VAS scores &lt;= 3 at each follow-up time point was also investigated. Statistical significance was set at P &lt; 0.05.

RESULTS

Twenty-seven men (62.4%) and 17 women (38.6%) were enrolled in this study. The mean age was 54.5 years (range 31-81). The average follow-up period after the operation was 15.4 months (range 3.7-30.8). The mean preoperative VAS was 7.50 ± 1.21. The VAS scores at 1 week, 3 months, and the last follow-up were 4.36 ± 2.46, 3.20 ± 2.58, and 2.91 ± 2.74, respectively, showing a significant improvement in pain compared to before the operation (P &lt; 0.001 for all). The number of patients (percentage) with a VAS score of &lt;= 3 was 20 (45.5%), 28 (63.6%), and 31 (70.5%) of 44 patients at 1 week, 3 months, and the last follow-up, respectively. The number of patients (percentage) with excellent, good, fair, or poor satisfaction according to the Macnab criteria was 17 (38.6%), 9 (20.5%), 8 (18.2%), and 10 (22.7%) of 44, respectively. No patients experienced postoperative complications.

LIMITATIONS

This study was retrospective and included a small number of patients from a single center.

CONCLUSIONS

Although PCN for radiculopathy caused by FCDH is thought to have limitations because of the surrounding bony structure, the clinical outcome seemed favorable. If PCN is not contraindicated, it may be a viable treatment option for CR due to FCDH.

Search for an Axionlike Particle in B Meson Decays

Axionlike particles (ALPs) are predicted in many extensions of the standard model, and their masses can naturally be well below the electroweak scale. In the presence of couplings to electroweak bosons, these particles could be emitted in flavor-changing B meson decays. We report herein a search for an ALP, a, in the reaction B^{±}→K^{±}a, a→γγ using data collected by the BABAR experiment at SLAC. No significant signal is observed, and 90% confidence level upper limits on the ALP coupling to electroweak bosons are derived as a function of ALP mass, improving current constraints by several orders of magnitude in the range 0.175  GeV<m_{a}<4.78  GeV.

Search for Lepton Flavor Violation in ϒ(3S)→e^{±}μ^{∓}

We report on the first search for electron-muon lepton flavor violation (LFV) in the decay of a b quark and b antiquark bound state. We look for the LFV decay ϒ(3S)→e^{±}μ^{∓} in a sample of 118 million ϒ(3S) mesons from 27  fb^{-1} of data collected with the BABAR detector at the SLAC PEP-II e^{+}e^{-} collider operating with a 10.36 GeV center-of-mass energy. No evidence for a signal is found, and we set a limit on the branching fraction B[ϒ(3S)→e^{±}μ^{∓}]<3.6×10^{-7} at 90% C. L. This result can be interpreted as a limit Λ_{NP}/g_{NP}^{2}>80  TeV on the energy scale Λ_{NP} divided by the coupling-squared g_{NP}^{2} of relevant new physics (NP).

Search for Darkonium in e^{+}e^{-} Collisions

Collider searches for dark sectors, new particles interacting only feebly with ordinary matter, have largely focused on identifying signatures of new mediators, leaving much of dark sector structures unexplored. In particular, the existence of dark matter bound states (darkonia) remains to be investigated. This possibility could arise in a simple model in which a dark photon (A^{'}) is light enough to generate an attractive force between dark fermions. We report herein a search for a J^{PC}=1^{--} darkonium state, the ϒ_{D}, produced in the reaction e^{+}e^{-}→γϒ_{D}, ϒ_{D}→A^{'}A^{'}A^{'}, where the dark photons subsequently decay into pairs of leptons or pions, using 514  fb^{-1} of data collected with the BABAR detector. No significant signal is observed, and we set bounds on the γ-A^{'} kinetic mixing as a function of the dark sector coupling constant for 0.001<m_{A^{'}}<3.16  GeV and 0.05<m_{ϒ_{D}}<9.5  GeV.

Tracheostomy Following Anterior Cervical Discectomy and Fusion With Plating in Trauma Patients: Is It Safe?

Objective

This study aimed to evaluate the safety and necessity of tracheostomy after anterior cervical discectomy and fusion (ACDF) with plating, despite the close proximity of the two surgical skin incisions.

Methods

Sixty-three patients with traumatic cervical fractures or spinal cord injury (SCI) who underwent single-level ACDF and plating between January 2014 and June 2019 were included in this study. The patients included 45 men and 18 women, with a mean age of 48.5 years. A retrospective analysis of the patients’ demographic data, level of injury, radiological findings, and neurological status was performed based on the American Spinal Injury Association (ASIA), open tracheostomy, and decannulation rate. Additionally, risk factors necessitating tracheostomy were statistically analyzed.

Results

Eighteen patients (28.5%) required subsequent open tracheostomy. Among them, 11 patients were successfully decannulated, four patients could not be decannulated during the follow-up period, and three patients died of unrelated complications. The median interval from ACDF with plating to open tracheostomy was 9.6 days (range, 5–23 days). On the basis of neurological status, ASIA A and B patients (p<0.001), high signal intensity on T2-weighted-magnetic resonance (MR) images (p=0.001), and major cervical fracture and dislocation were significant risk factors for tracheostomy (p=0.02). No patient showed evidence of significant soft tissue, bony infection, or nonunion during the follow-up period.

Conclusion

Independent tracheostomy did not increase the risk of infection or nonunion despite the close proximity of the two surgical skin incisions.

Neurological Deterioration Immediately After Lumbar Surgery: Anesthetic Consideration for Co-existing Cervical Lesion: A Case Report

Most spine surgeons and anesthesiologists believe that the risk of spinal cord injury (SCI) during intubation is mainly due to mechanical compression of the spinal cord due to cervical spine movement in cases of undiagnosed but severe cervical lesions. With this reasoning, difficult intubation, which is more frequently encountered in patients with preexisting cervical diseases, is likely to result in SCI. Several reports have described SCI after non-cervical surgery in patients previously diagnosed with cervical myelopathy and a chronically compressed cervical cord; however, to date, there is less acknowledgement of SCI in patients with undiagnosed cervical myelopathy. Here, we report a painful experience of neurological deterioration that developed immediately after elective lumbar decompressive surgery in a 76-year-old man. The possible mechanism behind these unexpected complications is discussed in a review of the literature.

Pyogenic Andersson Lesion in a Patient With Ankylosing Spondylitis

Although the exact etiology of the Andersson lesion (AL) remains unclear, it is known to occur mostly in patients with long-standing ankylosing spondylitis (AS). Among the various theories for the etiology of AL, repetitive trauma and inflammatory causes are the most common. The histopathological appearance of the AL in this report was consistent with that of chronic inflammation without any infection. Pyogenic ALs in the context of AS are extremely rare; to the best of our knowledge, positive cultures of this lesion in bone biopsies have never been reported. Herein, we report a rare case of a pyogenic AL with a positive culture and discuss a relevant review of the literature.