fiber optics in orthopedics

BACKGROUND: In bone sarcomas, chemotherapy has improved the prognosis with advances in diagnostic and surgical technologies, which has led to attempts to save limbs. As early detection and multidisciplinary treatment have improved the survival rate, curative surgery is considered for selected patients with metastatic bone carcinomas. Limb salvage procedures may vary in relation to the reconstruction method, which is accompanied by different complications. To overcome them, we devised a novel concept, in-situ local tumor ablation and recycling machine based on radiofrequency (RF)-induced heating and intended experiments to demonstrate its feasibility...

BACKGROUND: No single graft type has been shown to have a benefit in acetabular labral reconstruction. The native labrum and lateral meniscus share many similarities, suggesting that the meniscus may be a promising source of graft material in labral reconstruction. QUESTIONS/PURPOSES: Using a pig model, we sought to evaluate the healing process of fresh-frozen meniscus allograft for acetabular reconstruction by assessing (1) MRI and macroscopic observations of the meniscus allograft; (2) histologic appearance and immunohistologic evaluation of the meniscus allograft, native meniscus, and labrum; (3) microscopic assessment of the native labrum and meniscus via scanning electron microscopy; and (4) biomechanical assessment of tensile properties...

PURPOSE: Develop a spectroscopic method to assess cartilage thickness during the arthroscopic examination. METHODS: Currently, arthroscopy assesses cartilage damage visually; outcomes are based on the surgeon's subjective experience. Light reflection spectroscopy is a promising method for measuring cartilage thickness based on the absorption of light by the subchondral bone. In the presented study, in vivo diffuse optical back reflection spectroscopic measurements were acquired by gently placing an optical fibre probe on different locations of the articular cartilage of 50 patients during complete knee replacement surgery...

There is a critical need in orthopedic and orthodontic clinics for enhanced implant-bone interface contact to facilitate the quick establishment of a strong and durable connection. Surface modification by bioactive multifunctional materials is a possible way to overcome the poor osteoconductivity and the potential infection of Ti-based implants. Ti-25Zr biometallic alloy was prepared by powder metallurgy technique and then coated by Nano-composite fiber using electrospinning. Ceramic Nanocompound (CaTiO3 , BaTiO3 ) was used as filler material and individually added to polymeric matrices constructed from the blend of polycaprolactone/chitosan...

Accuracy in spinal fusion varies greatly depending on the experience of the physician. Real-time tissue feedback with diffuse reflectance spectroscopy has been shown to provide cortical breach detection using a conventional probe with two parallel fibers. In this study, Monte Carlo simulations and optical phantom experiments were conducted to investigate how angulation of the emitting fiber affects the probed volume to allow for the detection of acute breaches. Difference in intensity magnitude between cancellous and cortical spectra increased with the fiber angle, suggesting that outward angulated fibers are beneficial in acute breach scenarios...

The aim of the study was to design a construct based on a nasal septal cartilage plate providing required cell differentiation in different layers to replace a deep osteochondral defect and develop an algorithm of chemical and physical effect sequence to create non-immunogenic two-layer porous structure with requisite elasto-mechanical properties. MATERIALS AND METHODS: The plates derived from porcine nasal septal hyaline cartilage covered by perichondrium were multi-stage treated including freezing, equilibrating in a hypotonic saline solution (type I specimens); trypsinization, point IR-laser effect, re-trypsinization (type II specimens); a stabilizing effect of crosslinking agents - glyceraldehyde/ribose in an acidic medium - washing (type III specimens)...

Orthopedics (also - orthopedic surgery) is a field of medicine that deals with diseases, defects, infections, tumors and injuries of the skeletal system, joints and muscles in the human body. The term orthopedics (Greek Orthos = alignment, Pais = child) was first coined in 1741 by the French surgeon Nicolas Andry de Bois-Regard, from Lyon in France, to describe correction and prevention of spinal deformities in children. Only in the second half of the 18th century, did orthopedics separate from general surgery and became a separate specialty in medicine...

BACKGROUND: Perioperative visual loss is one of the rare but devastating complications of anesthesia and surgery. The incidence of less severe or even subclinical postoperative visual dysfunction is unknown. Therefore, we decided to perform a pilot prospective observational clinical study to evaluate whether structural changes of the retina can be detected in patients undergoing elective orthopaedic surgery by optical coherence tomography (OCT). METHODS: Adult patients indicated for elective knee replacement surgery with the absence of known retinal or optic nerve disease were included...

The paper describes a multimode-interference-effect-based single-mode-multimode-single-mode (SMS) fiber optic sensing system for wide-range displacement monitoring on an Ilizarov orthopedic external fixation device. Displacement measurement is implemented as the uniform extension of a spring, which is connected to an SMS optical fiber displacement sensor, allowing full displacement characterization. SMS fiber structures are used together with a macrobending-fiber-based interrogation system to measure temperature perturbation and hence eliminate its effect on the displacement measurement...

Intramedullary nailing is a routine orthopedic procedure used for treating fractures of femoral or tibial shafts. A critical part of this procedure involves the drilling of pilot holes in both ends of the bone for the placement of the screws that will secure the IM rod to sections of the fractured bone. This step introduces a risk of soft tissue damage because the drill bit, if not stopped in time, can transverse the bone-tissue boundary into the overlying muscle, causing unnecessary injury and prolonging healing time due to periosteum damage...

BACKGROUND: Neurofibromatosis 1 (NF1) presents a wide range of clinical manifestations, including bone alterations. Studies that seek to understand cellular and molecular mechanisms underlying NF1 orthopedic problems are of great importance to better understand the pathogenesis and the development of new therapies. Dental pulp stem cells (DPSCs) are being used as an in vitro model for several diseases and appear as a suitable model for NF1. The aim of this study was to evaluate in vitro chondrogenic differentiation of DPSCs from individuals with NF1 using two-dimensional (2D) and three-dimensional (3D) cultures...

Arthroscopy is a minimal invasive surgical technique to treat joint disorders with the use of fiber optics for indirect vision and small surgical tools. The first endoscopic direct inspection of the knee joint was documented at the beginning of the 20th century; however, the clinical practice of arthroscopy started only fifty years later. The "historical fathers" of surgical arthroscopy were Kenji Takagi from Japan and Eugen Bircher from Switzerland. The arthroscopes had become safer and more dependable since the 1970's with the introduction of fiber optics, while vision became easier with the invention of television...

Damage to knee articular ligaments causes important functional problems and adversely affects particularly the stability of the knee joint. Several methods were developed in order to repair damage to the anterior cruciate ligament (ACL), which employ autografts, allografts, as well as synthetic ligaments. One such synthetic scaffold, the ligament advanced reinforcement system (LARS) synthetic ligament is made of non-absorbing polyethylene terephthalate fibers whose structure allow tissue ingrowths in the intra-articular part, improving the stability of the joint...

BACKGROUND: The main objective of the present study was to investigate chemical composition and possible cyto/genotoxic potential of several medical implant materials commonly used in total hip joint replacement. METHODS: Medical implant metal alloy (Ti6Al4V and CoCrMo) and high density polyethylene particles were analyzed by energy dispersive X-ray spectrometry while toxicological characterization was done on human lymphocytes using multi-biomarker approach. RESULTS: Energy dispersive X-ray spectrometry showed that none of the elements identified deviate from the chemical composition defined by appropriate ISO standard...

Pulsed high-intensity focused ultrasound (HIFU) is proposed as a new alternative treatment for contracture of dense fibrous tissue. It is hypothesized that the pulsed-HIFU can release the contracted tissues by attenuating tensile stiffness along the fiber axis, and that the stiffness reduction can be quantitatively monitored by change of B-mode images. Fresh porcine tendons and ligaments were adapted to an ex vivo model and insonated with pulsed-HIFU for durations ranging from 5 to 30 min. The pulse length was 91 µs with a repetition frequency of 500 Hz, and the peak rarefactional pressure was 6...

The aim of this work is to show the possibility of using fiber optic sensors to instrument inside parts of an artificial maxilla and measure internal tension transmitted by the orthodontic and orthopedic appliances to the dentition and the adjacent bone. Bragg gratings written in a standard optical fiber were used to monitor the maxillary teeth and a multiplexed fiber was used to monitor the surface of the maxillary bone, transversally to the longest axis of the teeth. A Universal Test Machine was used to evaluate the sensitivity of the sensor to the vertical and lateral forces applied on the teeth...

BACKGROUND: There is no consensus on the role of preoperative cervical spine radiographs to screen for instability in patients with rheumatoid arthritis (RA). OBJECTIVES: This study aimed to evaluate the preoperative use of cervical spine radiographs in patients with RA undergoing preoperative anesthesia assessment and to determine whether preoperative radiographic findings influenced anesthesia delivery techniques. METHODS: We reviewed all medical records of RA patients who underwent surgical procedures requiring general anesthesia with airway intubation or monitored anesthesia care without airway intubation...

PURPOSE: To report the clinical, ophthalmic, extraophthalmic, and genetic characteristics of nail-patella syndrome (NPS) in a Chilean family and to investigate the expressivity of open angle glaucoma (OAG) and ocular hypertension (OHT) in the family members. METHODS: Five family members affected with NPS and two unaffected members underwent a complete ophthalmologic examination, including computerized visual field, optical coherence tomography (OCT) of the optic disc and ultrasound pachymetry...

Fiberoptic intubation is the most reliable method in patients with difficult airways, but it may be difficult in patients with restricted neck movement. The intubating laryngeal mask airway facilitates fiberoptic intubation, but its insertion may also be difficult in some circumstances. We experienced a case of successful tracheal intubation using the Pentax-AWS (Airway Scope) after failed fiberoptic intubation and failed insertion of the intubating laryngeal mask. A 74-year-old man who had undergone fixation of the cervical spine required reoperation...

The case of a female patient is reported where difficulty in securing the airway occurred during a reconstructive intervention following partial mandibular resection. During previous surgery the last of which was 2 months prior to this, endotracheal intubation was carried out with the GlideScope videolaryngoscope, but now the vocal chords could not be viewed with the GlideScope. Attempts at fiber optic intubation under general anesthesia were also unsuccessful. A "cannot ventilate, cannot intubate" situation ensued and an emergency tracheotomy was carried out...