Biomedical subjects
Publications and source records attributed to M A Towler.
A new needle holder is described that has jaws metallurgically bonded with tungsten carbide particles that enhance needle holding security without causing sutural damage during instrument ties. Scissors have also been incorporated into the needle holder to cut sutures. One ringlet on a handle has been offset to facilitate retrieval of the needle holder from a flat surface.
A new beveled, conventional cutting edge needle has been developed with superior performance characteristics over those of other conventional cutting edge needles. It is composed of a unique stainless steel, ASTM 45500, that has been heat-treated after the curving process to enhance its resistance to bending. The angle of presentation of its cutting edges has been decreased to enhance needle sharpness. On the basis of the results of experimental and clinical investigations, this new needle is recommended for closure of lacerations.
It is the purpose of this report to design, develop, and evaluate a needle holder whose jaws improve needle-holding security without altering the geometry of the curved surgical needle. The configuration of the jaws of this new needle holder is curved, conforming to the curvature of the surgical needle. A biomechanical study of this curved surgical needle holder demonstrates that it holds the curved needle securely without needle deformation.
The mechanical performance of disposable Webster surgical needle holders supplied by three different surgical instrument companies was determined by recording the forces (clamping moment) applied by the different needle holder jaws to curved surgical needles. This investigation demonstrated that there was a large variability in the mechanical performance of the disposable needle holders supplied by each surgical instrument company. In addition, the mechanical performance of the disposable needle holder of each surgical instrument company was distinctly different.
The purpose of this study is to evaluate the biomechanical performance of laser-drilled and channel needle swages. The laser-drilled swages have a more uniform circumference that encounters lower drag forces than the channel needle swages. In addition, the length of the laser-drilled hole is shorter than that of the channel needles, allowing the physician to grasp the laser-drilled needle close (3 mm) to the needle end without deformation. These benefits of laser-drilled swages indicate that they should replace all channel needles.
Molten metal burns of the feet remain a common injury to foundry workers. A case is reported of a foundry worker who sustained circumferential molten metal burns of the distal foot and toes necessitating amputation of four toes. This severe injury could easily have been prevented by the use of protective footwear and spats.
Detrusor-external sphincter dyssynergia (DESD) is a neuropathic disorder of micturition that exists when the simultaneous contractions of the detrusor muscle and external urethral sphincter oppose each other. When the external urethral sphincter contracts during a detrusor contraction, functional urinary outflow obstruction occurs by the increased urethral resistance. This loss of coordination between the bladder and its outlet is associated with a high risk for serious urologic complications, such as vesicoureteral reflux, hydronephrosis, and urosepsis. This report describes a male multiple sclerosis patient with DESD who developed functional outlet obstruction with urosepsis and discusses the diagnosis and treatment of this potentially life-threatening voiding dysfunction.
The purpose of this study was to determine the influence of emergency physician's tying technique on knot security using 2-0 and 4-0 monofilament and multifilament nylon sutures. Using an Instron Tensile Tester and a portable tensiometer, knot security was achieved with these sutures using four-throw square knots (1 = 1 = 1 = 1). After didactic and psychomotor skill training, medical students were taught to construct the four-throw square knot using either a two-hand tie or an instrument tie. Using the portable tensiometer, their knot tying techniques were judged to be superior to those used by emergency physicians. The emergency physician's faulty technique can easily be corrected by didactic information and psychomotor skill training.
A new, innovative packaging system for surgical needles and sutures has been developed that meets the special needs of emergency physicians, surgeons, and operating personnel. This packaging system consists of an overwrap, or breather pouch, as well as an innerwrap containing the needle swaged to a surgical suture. The flaps of the overwrap are offset and serrated to facilitate the opening and sterile transfer of the inner packet to the sterile field. The inner packet contains either a plastic labyrinth or craft board that maintains the suture as straight as possible until knot construction. The needle swaged to a suture is parked in foam to protect its sharp cutting edges and point.
Dr. Richard F. Edlich, Distinguished Professor of Plastic Surgery and Biomedical Engineering, recently received the Thomas Jefferson Award, the highest honor that can be bestowed upon a faculty member at the University of Virginia. Reflections of his "Academical Village" are presented to share ideas from the teaching environment he has created.
Air splints have been used for immobilization of fractures, skin graft stabilization and preprosthetic rehabilitation of the amputated lower limb. The purpose of this clinical study was to assess its use as a hydrofitness device to facilitate walking reeducation, to produce muscle strengthening and to increase joint extensibility in patients with weak legs. The performance of the air splint as a hydrofitness device was compared to that of the new foam hydrofitness device. The parameters used to assess the performance of these devices included durability, application and removal times, joint extensibility and the magnitude of the fluid drag forces. On the basis of this evaluation, the performance of the foam hydrofitness device was judged to be superior to that of the air splint for leg musculoskeletal conditioning.
Several devices (flexible ladder, towel, cord) have been recommended for use in physical therapy to enhance the range of motion of the joints involved in the behind-the-back reach test. The purpose of this study was to evaluate the biomechanical performance of these devices by measuring the maximum forces applied to the devices during the behind-the-back reach test. The performance of all of these devices during the behind-the-back reach test was remarkably similar.
The purpose of this study was to determine the position and size of flotation devices that permit deep-water exercise with the exerciser's thoracolumbar spine in a vertical position and without restriction of movement of the arms and legs. The buoyant force of the flotation device had to be at least 94.0 N to allow the exerciser to be suspended in water with the head above water. The position of the flotation devices had considerable influence on the thoracolumbar angle. When the large pad with a buoyant force of 55.0 N covered the lower abdominal wall and the small pad with a buoyant force at 39.0 N was located over the lower back, the exerciser's thoracolumbar spine assumed an almost vertical position. Anterior placement of the flotation devices resulted in marked extension of the thoracolumbar spine. Conversely, posterior placement of the buoyant devices resulted in flexion of the thoracolumbar spine. On the basis of these results, an ideal flotation device for deep-water exercise can now be developed.
A new compound curved needle has been developed for skin and skin-graft closure from a unique stainless steel alloy, American Society for Testing Materials (ASTM) 45500. This needle has a short, straight, sharpened point with a reverse cutting edge and a curved distal section. In spite of its geometry, it exhibits sharpness and resistance to bending and breakage similar to that of a needle with a single radius of curvature that is manufactured from the same alloy. The design of this new needle enables the surgeon to pass it through the skin with greater accuracy to a controlled depth and length of bite.
A new leg hydrofitness device has been designed for aquatic exercise. It consists of three separate rectangular-shaped buoyant floats that are positioned around the ankle. A clinical trial indicates its potential value for walking reeducation, strengthening leg muscles, and enhancing joint extensibility.
A new support bandage has been developed that is cohesive, sticking only to itself without adhering to the skin. It is warpknit product, impregnated with an acrylic compound, that consists of individual panels connected by a hinge stitch. It exhibits moderate extensibility under low loads which allows the health professional to apply the bandage so that it gives firm support to the underlying tissue without constriction. Its macroporous structure permits sufficient water vapor transmission to allow the underlying skin and/or wound to remain dry.
Hydrotherapy is based on several important bioengineering principles that permit the design and development of aquatic exercise devices, techniques and programs. These principles involve several forces (buoyancy, drag, inertia), hydrostatic pressure and the specific heat of water. By acquiring a knowledge of these bioengineering principles, an individualized exercise program can be prescribed that will enhance physical fitness which is associated with desirable psychological changes.
The walker is a mobility aid that provides a portable base of support. People of all ages use different kinds of walkers for a variety of reasons. With the correct walker, many people stroll along at the same pace as their companion. Today, walkers are available in a variety of styles and colors and have numerous accessories. It is the purpose of this article to describe the various types and models of walkers and accessories that are available. Our goal is not to recommend or rate the walkers but to help you find the right walker. The ultimate selection of a walker will depend on a cooperative effort between the physiatrist, physical therapist, and medical equipment supplier. Before you purchase a walker you should test it out to decide if it is the right one for you. The physical therapist who supplies your walker should adjust for your height and should check the physical fit of the equipment. Moreover, the physical therapist should demonstrate the proper gait for walking. During the past few years radical changes have occurred in the design and style of walkers. We expect this trend to continue with more attractive, easier-to-use products to be introduced regularly. If you think that your walker is outdated and is not adapting to your lifestyle, talk with your physiatrist regarding alternatives. Today, walkers are as different as their users. Find the best one for you by taking a test walk in your home and community.