Interleukin-6 transiently promotes proliferation of osteoclast precursors and stimulates the production of inflammatory mediators.

Background: Clinical data and phenotypes of several in vivo models demonstrated that interleukin-6 (IL-6) is an essential positive regulator in inflammation-induced bone loss. However, how IL-6 affect bone resorption and the osteoclast differentiation remains in debate. In this study we elucidate the cellular responses of receptor activator of nuclear factor kappa-Β ligand (RANKL)-stimulated RAW254.

Cranio-Vertebral Junction Triangular Area: Quantification of Brain Stem Compression by Magnetic Resonance Images.

(1) Background: Most of the currently used radiological criteria for craniovertebral junction (CVJ) were developed prior to the popularity of magnetic resonance images (MRIs). This study aimed to evaluate the efficacy of a novel triangular area (TA) calculated on MRIs for pathologies at the CVJ. (2) Methods: A total of 702 consecutive patients were enrolled, grouped into three: (a) Those with pathologies at the CVJ ( = 129); (b) those with underlying rheumatoid arthritis (RA) but no CVJ abnormalities ( = 279); and (3) normal (control; = 294).

Suture Repair in Endoscopic Surgery for Craniovertebral Junction.

Objective: Endoscopic approaches to the craniovertebral junction (CVJ) have been established as viable and effective surgical treatments in the past decade. One of the major complications is leakage of the cerebrospinal fluid (CSF). This study aimed to investigate the efficacy and feasibility of suture closure at the nasopharyngeal mucosa upon durotomy.

Disappearance of Anterior Cervical Corpectomy Cage.

Although cage subsidence and dislodgement are not uncommon in anterior cervical spine surgery, missing cages have seldom been reported. This is the first report of the disappearance of a metallic corpectomy cage after anterior cervical fusion. A 63-year-old man, who had a history of ankylosing spondylitis and diabetes mellitus, was involved in a motor vehicle accident that broke his neck.

Differences in fixation strength among constructs of atlantoaxial fixation.

OBJECTIVETo avoid jeopardizing an aberrant vertebral artery, there are three common options in placing a C2 screw, including pedicle, pars, and translaminar screws. Although biomechanical studies have demonstrated similar strength among these C2 screws in vitro, there are limited clinical data to address their differences in vivo. When different screws were placed in each side, few reports have compared the outcomes.

Enhanced Recovery After Surgery™ Awake Minimally-Invasive Transforaminal Lumbar Interbody Fusion: 2-Dimensional Operative Video.

This video demonstrates the awake endoscopic minimally-invasive transforaminal lumbar interbody fusion (MIS-TLIF) used in our institution's developing Enhanced Recovery After Surgery program. This technique relies on 6 key components, including (1) conscious sedation, (2) endoscopic visualization, (3) long-acting local anesthesia, (4) an expandable interbody device, (5) osteobiologics, and (6) percutaneous instrumentation. In joining these technologies, this procedure embodies the principles of minimally invasive surgery while achieving excellent clinical outcomes.

A highly integrated single-mode 1064 nm laser with 8.5 kHz linewidth for dual-wavelength active optical clock.

Without exploiting any frequency selective elements, we have realized a highly integrated, single-mode, narrow-linewidth Nd:YAG 1064 nm laser, which is end-pumped by the 808.6 nm diode laser in an integrated invar cavity. It turns out that each 1064 nm laser achieves a most probable linewidth of 8.

Compact Rb optical frequency standard with 10 stability.

We achieved a low-cost and small-sized Rb optical frequency standard based on Rb 5S → 6P transition with 10 stability, which is comparable with that of the best 532 nm I optical frequency standards. In this system, we directly lock the 420 nm diode laser on the 5S F = 3 → 6P F = 4 hyperfine transition line without an additional Pound-Drever-Hall pre-locking system. The signal-to-noise-ratio reaches as high as 350 000 when the averaging time is at 1 s.

A Faraday laser lasing on Rb 1529 nm transition.

We present the design and performance characterization of a Faraday laser directly lasing on the Rb 1529 nm transition (Rb, 5P  - 4D ) with high stability, narrow spectral linewidth and low cost. This system does not need an additional frequency-stabilized pump laser as a prerequisite to preparing Rb atom from 5S to 5P excited state. Just by using a performance-improved electrodeless discharge lamp-based excited-state Faraday anomalous dispersion optical filter (LESFADOF), we realized a heterogeneously Faraday laser with the frequency corresponding to atomic transition, working stably over a range of laser diode (LD) current from 85 mA to 171 mA and the LD temperature from 11 °C to 32 °C, as well as the 24-hour long-term frequency fluctuation range of no more than 600 MHz.

Is cervical disc arthroplasty good for congenital cervical stenosis?

OBJECTIVE Cervical disc arthroplasty (CDA) has been demonstrated to be as safe and effective as anterior cervical discectomy and fusion (ACDF) in the management of 1- and 2-level degenerative disc disease (DDD). However, there has been a lack of data to address the fundamental discrepancy between the two surgeries (CDA vs ACDF), and preservation versus elimination of motion, in the management of cervical myelopathy associated with congenital cervical stenosis (CCS). Although younger patients tend to benefit more from motion preservation, it is uncertain if CCS caused by multilevel DDD can be treated safely with CDA.

Can segmental mobility be increased by cervical arthroplasty?

OBJECTIVE Many reports have successfully demonstrated that cervical disc arthroplasty (CDA) can preserve range of motion after 1- or 2-level discectomy. However, few studies have addressed the extent of changes in segmental mobility after CDA or their clinical correlations. METHODS Data from consecutive patients who underwent 1-level CDA were retrospectively reviewed.

Stepwise illustration of teeth-fixation semi-constrained cervical disc arthroplasty.

There are many kinds of artificial discs available for cervical disc arthroplasty (CDA), with various designs of fixation and articulation mechanisms. Each of these designs has different features and theoretically fits most optimally in selected types of patients. However, there has been insufficient literature to guide individualized selection among these CDA devices.

Hybrid Corpectomy and Disc Arthroplasty for Cervical Spondylotic Myelopathy Caused by Ossification of Posterior Longitudinal Ligament and Disc Herniation.

Objective: The combination of anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) has been demonstrated to be effective for multilevel cervical spondylotic myelopathy (CSM); however, the combination of ACCF and cervical disc arthroplasty (CDA) for 3-level CSM has never been addressed.

Methods: Consecutive patients (>18 years of age) with CSM caused by segmental ossification of posterior longitudinal ligament (OPLL) and degenerative disc disease (DDD) were reviewed. Inclusion criteria were patients who underwent hybrid ACCF and CDA surgery for symptomatic 3-level CSM with OPLL and DDD.

Minimally invasive transforaminal lumbosacral interbody fusion.

In minimally invasive spinal fusion surgery, transforaminal lumbar (sacral) interbody fusion (TLIF) is one of the most common procedures that provides both anterior and posterior column support without retraction or violation to the neural structure. Direct and indirect decompression can be done through this single approach. Preoperative plain radiographs and MR scan should be carefully evaluated.

Risk of spinal cord injury in patients with cervical spondylotic myelopathy and ossification of posterior longitudinal ligament: a national cohort study.

OBJECTIVE This study aimed to estimate the risk of spinal cord injury (SCI) in patients with cervical spondylotic myelopathy (CSM) with and without ossification of posterior longitudinal ligament (OPLL). Also, the study compared the incidence rates of SCI in patients who were managed surgically and conservatively. METHODS This retrospective cohort study covering 15 years analyzed the incidence of SCI in patients with CSM.

Primary Endoscopic Transnasal Transsphenoidal Surgery for Giant Pituitary Adenoma.

Objectives: Giant pituitary adenoma (>4 cm) remains challenging because the optimal surgical approach is uncertain.

Methods: Consecutive patients with giant pituitary adenoma who underwent endoscopic transnasal transsphenoidal surgery (ETTS) as the first and primary treatment were retrospectively reviewed. Inclusion criteria were tumor diameter ≥4 cm in at least 1 direction, and tumor volume ≥10 cm(3).

Should Cervical Disc Arthroplasty Be Done on Patients with Increased Intramedullary Signal Intensity on Magnetic Resonance Imaging?

Objective: Several trials from the U.S. Food and Drug Administration have demonstrated the success of cervical disc arthroplasty (CDA) in patients with degenerative disc disease causing radiculopathy, myelopathy, or both.

Hydrocephalus Caused by Fat Embolism: A Rare Complication of Atlanto-Axial Fixation for Odontoid Fractures.

Background And Importance: Odontoid fracture is not uncommon and surgical treatment that uses posterior screw/rod fixation is an acceptable option. This is the first report of delayed hydrocephalus due to subarachnoid fat migration as a complication of posterior atlanto-axial (AA) fixation.

Case Description: A 27-year-old man underwent posterior C1 lateral mass and C2 pedicle screw fixation for a recent Anderson-D'Alonzo type 2 odontoid fracture.

Differences between C3-4 and other subaxial levels of cervical disc arthroplasty: more heterotopic ossification at the 5-year follow-up.

OBJECTIVE Several large-scale clinical trials demonstrate the efficacy of 1- and 2-level cervical disc arthroplasty (CDA) for degenerative disc disease (DDD) in the subaxial cervical spine, while other studies reveal that during physiological neck flexion, the C4-5 and C5-6 discs account for more motion than the C3-4 level, causing more DDD. This study aimed to compare the results of CDA at different levels. METHODS After a review of the medical records, 94 consecutive patients who underwent single-level CDA were divided into the C3-4 and non-C3-4 CDA groups (i.

The Effect of Lumbar Lordosis on Screw Loosening in Dynesys Dynamic Stabilization: Four-Year Follow-Up with Computed Tomography.

Introduction: This study aimed to evaluate the effects of Dynesys dynamic stabilization (DDS) on clinical and radiographic outcomes, including spinal pelvic alignment.

Method: Consecutive patients who underwent 1- or 2-level DDS for lumbar spondylosis, mild degenerative spondylolisthesis, or degenerative disc disease were included. Clinical outcomes were evaluated by Visual Analogue Scale for back and leg pain, Oswestry Disability Index, and the Japanese Orthopedic Association scores.

Dynesys dynamic stabilization-related facet arthrodesis.

OBJECTIVE Dynamic stabilization devices are designed to stabilize the spine while preserving some motion. However, there have been reports demonstrating limited motion at the instrumented level of the lumbar spine after Dynesys dynamic stabilization (DDS). The causes of this limited motion and its actual effects on outcomes after DDS remain elusive.