Alignment transport between ultracold polar molecules.

We propose an array of ultracold polar molecules as a platform to study alignment transport between molecules. We envision a polar molecule being aligned with an intense off-resonant laser field whose alignment migrates to a nearby molecule due to dipole-dipole interactions. Our results show that the transport of the alignment is due to a complex interplay between electric field-driven excitations and dipole-dipole interactions.

Twenty-Year Radiographic Outcomes Following Single-Level Cervical Disc Arthroplasty: Results From a Prospective Randomized Controlled Trial.

Study Design: Prospective randomized controlled trial.

Objective: Compare range of motion (ROM) and adjacent segment degeneration (ASD) following cervical disc arthroplasty (CDA) versus anterior cervical discectomy and fusion (ACDF) at 20-year follow-up.

Summary Of Background Data: Anterior cervical discectomy and fusion is the standard of treatment for single-level cervical disc degeneration causing radiculopathy.

Model of charge transfer collisions between C and slow ions.

A semiclassical model describing the charge transfer collisions of C fullerene with different slow ions has been developed to analyze available observations. These data reveal multiple Breit-Wigner-like peaks in the cross sections, with subsequent peaks of reactive cross sections decreasing in magnitude. Calculations of charge transfer probabilities, quasi-resonant cross sections, and cross sections for reactive collisions have been performed using semiempirical interaction potentials between fullerenes and ion projectiles.

Characterizing stages of COVID-19 epidemics: a nonlinear physics perspective based on amplitude equations.

The relevant dynamics underlying COVID-19 waves is described from an amplitude space perspective. To this end, the amplitude dynamics of infected populations is considered in different stages of epidemic waves. Eigenvectors and their corresponding amplitudes are derived analytically for low-dimensional models and by means of computational methods for high-dimensional models.

Long-Term Radiographic and Functional Outcomes of Patients With Absence of Radiographic Union at 2 Years After Single-Level Anterior Cervical Discectomy and Fusion.

Study Design: Retrospective radiographic investigation.

Objective: To evaluate the long-term radiographic and functional outcomes of patients in whom there is absence of radiographic union at 2 years after single-level anterior cervical discectomy and fusion (ACDF).

Methods: Thirty-one patients were evaluated at standard postoperative time intervals per index trial protocol.

Boids in a loop: Self-propelled particles within a flexible boundary.

We numerically explore the behavior of repelling and aligning self-propelled polar particles (boids) in two dimensions enclosed by a damped flexible and elastic loop-shaped boundary. We observe disordered, polar ordered, jammed, and circulating states. The latter produce a rich variety of boundary shapes, including circles, ovals, irregulars, ruffles, or sprockets, depending upon the bending moment of the boundary and the boundary to particle mass ratio.

Far Lateral/Extraforaminal Approaches for Microdiscectomy and Foraminal Decompression in the Lumbar Spine.

Far lateral approaches to the lumbar spine are uncommon procedures but are essential techniques for spine surgeons to understand and master for the treatment of extraforaminal disk herniations and foraminal stenosis. We present our preferred approaches for open and minimally invasive techniques to perform extraforaminal decompressions and/or discectomies in the lumbar spine.

Evaluation of DIAM™ Spinal Stabilization System for lower lumbar disc degenerative disease: A randomized, prospective, single-site study.

Objective: To determine the efficacy of DIAM Spinal Stabilization System compared with nonoperative treatment for patients with low back pain and lower lumbar disc degenerative disease.

Methods: A single center collected prospective outcomes data on 38 patients randomized to an interspinous device or non-operative treatment for symptomatic lumbar degenerative disc disease with treatment crossover allowed at 6 months.

Results: At all postoperative timepoints out to 2-years, statistically significant improvements in ODI and back pain scores were observed with the interspinous device.

Functional Outcomes Associated With Adjacent-level Ossification Disease 10 Years After Cervical Disc Arthroplasty or ACDF.

Study Design: A retrospective review of a prospective, randomized control Food and Drug Administration (FDA) investigational device exemption trial comparing anterior cervical discectomy and fusion (ACDF) with Bryan cervical disc arthroplasty.

Objective: Determine the clinical significance of adjacent-level ossification disease (ALOD) on long-term functional outcomes after ACDF or arthroplasty.

Summary Of Background Data: ALOD occurs when the anterior longitudinal ligament and annulus adjacent to the index surgical level calcifies.

Biomechanical Analysis of the Cervical Spine Following Disc Degeneration, Disc Fusion, and Disc Replacement: A Finite Element Study.

Background: Discectomy and fusion is considered the "gold standard" treatment for clinical manifestations of degenerative disc disease in the cervical spine. However, clinical and biomechanical studies suggest that fusion may lead to adjacent-segment disease. Cervical disc arthroplasty preserves the motion at the operated level and may potentially decrease the occurrence of adjacent segment degeneration.

Does index level sagittal alignment determine adjacent level disc height loss?

Objective: The authors sought to compare the effect of index level sagittal alignment on cephalad radiographic adjacent segment pathology (RASP) in patients undergoing cervical total disc arthroplasty (TDA) or anterior cervical discectomy and fusion (ACDF).

Methods: This was a retrospective study of prospectively collected radiographic data from 79 patients who underwent TDA or ACDF and were enrolled and followed prospectively at two centers in a multicenter FDA investigational device exemption trial of the Bryan cervical disc prosthesis used for arthroplasty. Neutral lateral radiographs were obtained pre- and postoperatively and at 1, 2, 4, and up to 7 years following surgery.

No S.C.A.R.E. Protocol: A Streamlined Safety Protocol.

Introduction: Despite the proven success of anterior cervical surgery (ACS) postoperative issues can arise, with retropharyngeal hematoma (RH) being one of the most feared. A recent USA Today article highlighted the failed management and subsequent death of patients developing RH after ACS. The article calls into question the safety of performing ACS in an outpatient setting.

Single-Level Cervical Disc Arthroplasty with a Bryan Device.

Introduction: The anterior cervical approach for discectomy with modified distraction and milling tools (Video 1) provides an ideal method for surgical treatment of symptomatic discogenic disease and subsequent placement of an arthroplasty device.

Step 1 Patient Positioning: Position the patient supine on a radiolucent table that allows for anteroposterior and lateral fluoroscopic imaging.

Step 2 Surgical Approach: Use a standard Smith-Robinson approach to the anterior cervical spine at the index level of pathological involvement.

Long-term Clinical Outcomes of Cervical Disc Arthroplasty: A Prospective, Randomized, Controlled Trial.

Study Design: Prospective, randomized, single-center, clinical trial.

Objective: To prospectively examine the 7- and 10-year outcomes of cervical arthroplasty to anterior cervical discectomy and fusion (ACDF).

Summary Of Background Data: Degeneration of the cervical discs causing radiculopathy is a frequent source of surgical intervention, commonly treated with ACDF.

Comparison of Two Synthetic Bone Graft Products in a Rabbit Posterolateral Fusion Model.

Background: The drawbacks of iliac crest autograft as graft material for spine fusion are well reported. Despite continued modifications to improve bone healing capacity, the efficacy of synthetic graft materials as stand-alone replacements remains uncertain. The rabbit posterolateral fusion model is an established environment for testing of fusion concepts.

Comparison of Long-term Differences in Dysphagia: Cervical Arthroplasty and Anterior Cervical Fusion.

Study Design: Retrospective cohort study.

Objective: This study investigates the incidence of long-term dysphagia in cervical disc arthroplasty, and anterior cervical discectomy and fusion (ACDF) patients.

Summary Of Background Data: No long-term comparison of dysphagia between cervical arthroplasty and fusion patients has been published.

Erythema Ab Igne due to Heating Pad Use: A Case Report and Review of Clinical Presentation, Prevention, and Complications.

Erythema ab igne is an asymptomatic cutaneous condition caused by exposure to heat. Cases of erythema ab igne may prove to be diagnostically challenging due to lack of familiarity with the condition. While this dermatosis carries a favorable prognosis, nonmelanoma skin cancers have been reported to arise within lesions of erythema ab igne.

Efficacy of i-Factor Bone Graft versus Autograft in Anterior Cervical Discectomy and Fusion: Results of the Prospective, Randomized, Single-blinded Food and Drug Administration Investigational Device Exemption Study.

Study Design: A prospective, randomized, controlled, parallel, single-blinded noninferiority multicenter pivotal FDA IDE trial.

Objective: The objective of this study was to investigate efficacy and safety of i-Factor Bone Graft (i-Factor) compared with local autograft in single-level anterior cervical discectomy and fusion (ACDF) for cervical radiculopathy.

Summary Of Background Data: i-Factor is a composite bone substitute material consisting of the P-15 synthetic collagen fragment adsorbed onto anorganic bone mineral and suspended in an inert biocompatible hydrogel carrier.

Assessment of SiCaP-30 in a Rabbit Posterolateral Fusion Model with Concurrent Chemotherapy.

Chemotherapy derivatives of the rabbit posterolateral fusion model are considered a challenging environment in which to test bone graft materials. The purpose of this study was to determine the performance characteristics of SiCaP-30 as a bone graft substitute relative to autograft (iliac crest bone graft [ICBG]), Actifuse ABX and β-Tricalcium Phosphate-Bioactive Glass-Type I Collagen (βTCP-BG) in a rabbit posterolateral spine fusion model with concurrent chemotherapy treatment This was a randomized, controlled study in a laboratory setting with blinded assessment of fusion by manual palpation and flexibility testing. Sixty rabbits were entered into the study with 45 used for analysis.

Biomechanical Analysis of Cervical Disc Replacement and Fusion Using Single Level, Two Level, and Hybrid Constructs.

Study Design: A biomechanical study comparing arthroplasty with fusion using human cadaveric C2-T1 spines.

Objective: To compare the kinematics of the cervical spine after arthroplasty and fusion using single level, 2 level and hybrid constructs.

Summary Of Background Data: Previous studies have shown that spinal levels adjacent to a fusion experience increased motion and higher stress which may lead to adjacent segment disc degeneration.