Traumatic rupture of the tibialis posterior tendon after ankle fracture: a case report.

Degenerative tears of the posterior tibial tendon associated with chronic disease are well documented in the literature. Traumatic ruptures of this tendon, however, are much less common and consequently have received little attention. An association has been shown between pronation-external rotation ankle fractures and tears of the tendons that cross the medial aspect of the ankle, most commonly the posterior tibial tendon. In the present case report, we share our unique experience of an open-ankle fracture associated with the traumatic rupture of the posterior tibial tendon. This injury illustrates that soft-tissue injury must always be suspected concomitantly in the treatment of certain fractures on the basis of both mechanism of injury and fracture pattern.

Treatment of fractures of the fifth metatarsal: a prospective study.

Successful treatment of avulsion fractures of the base of the fifth metatarsal has been achieved using both short leg casts and soft (Jones) dressings. Sixty patients who presented to our institution were prospectively randomized to be treated with either a short leg cast or a soft (Jones) dressing for the purpose of assessing the efficacy of each treatment modality. Our results demonstrated that radiographic evidence of fracture healing was present in all patients by 65 days with 44 days representing the average elapsed time for such change. All patients returned to full weightbearing and full physical activity within 96 days. Significantly, the average length of recuperation for patients treated with a soft (jones) dressing was 33 days as compared to 46 days for those treated with a short leg cast. Also, the average modified foot score for patients treated in a soft dressing was 92 (excellent) compared to 86 (good) for patients treated in a short leg cast. We conclude that a soft dressing allows patients to return to pre-injury levels of activity faster than when treated in a short leg cast and without compromising clinical or radiographic union of avulsion fractures of the base of the fifth metatarsal.

Sintonia de controladores PID utilizando las reglas de ziegler y nichols basadas en oscilaciones de ciclo limite

El trabajo a continuacion, desarrolla un sistema de control basado en el algoritmo de control PID, cuyos parametros son ajustados, de manera automatica, mediante un experimento de sintonia fuera de linea. El primer capitulo las reglas de ajuste de los parametros del algoritmo de control PID de Ziegler y Nichols y la explicacion del metodo de ajuste automatico de parametros. Este, consiste en cerrar un lazo de realimentacion por medio de un relevador simetrico, llevando a la planta al limite de la estabilidad. Midiendo la amplitud y el periodo de las oscilaciones de ciclo limite, utilizamos las reglas de Ziegler y Nichols para calcular los parametros del algoritmo de control. El poder ajustar los parametros de manera automatica evita que se lleve manualmente a la planta al limite de la estabilidad, operacion que puede causar que esta, se descontrole al funcionar, accidentalmente, en un punto inestable. No se considera la posibilidad de que el ajuste de parametros se realice automaticamente dadas ciertas condiciones fijadas por el usuario, opcion que debe considerar ademas que las oscilaciones del experimento de sintonia no sobrepasen el limite maximo permitido. El segundo capitulo, presenta la teoria para la implementacion del controlador en cualquier sistema con microprocesador. Se desarrolla un algoritmo PID discreto, tomando en cuenta las modificaciones comunmente utilizadas en la industria del modelo matematico basico; se analizan las señales de control, datos y direccion requeridas para la interaccion del microprocesador con la planta y se describe para la interaccion del microprocesador con la planta y se describe la estructura de los programas. Finalmente se realiza una simulacion numerica para validar el estudio anterior. El tercer capitulo presenta el desarrollo del prototipo del controlador con opcion de ajuste automatico de parametros, utilizando el microcomputador TIMEX SINCLAIR 2068, explicando el hardware y software utilizado para su implementacion, basado en el capitulo anterior. Se explica tambien un ejemplo de aplicacion donde se controla el funcionamiento de un motor. Finalmente el cuarto capitulo presenta los costos estimados del prototipo y explica algunos aspectos que se deberan tomar en cuenta para un desarrollo comercial del mismo.

Coordination of benefits reduces double payments.

As a means of reducing the cost of duplicate health care coverage, the health insurance industry utilizes a mechanism called coordination of benefits (COB). The main purposes of COB are to limit recovery to 100 percent of actual charges and to assign insurers primary and secondary responsibilities to pay these charges. Nearly all health plans, including HMOs, Blue Cross/Blue Shield plans, and commercial insurers, coordinate benefits, mostly for group coverage, often on the basis of procedures found in state insurance codes. While COB provides an effective cost reduction mechanism to health insurers, several issues remain in its administration, including difficulties that arise when carriers refuse to pay, when HMO members self-refer, and when coordination is attempted with an uninsured plan.

Degenerative change in symptomatic scaphoid nonunion.

A retrospective radiographic analysis of 64 patients with symptomatic scaphoid nonunions without previous surgical treatment was accomplished. The results showed a high frequency of degenerative changes occurring in a predictable sequence. For nonunions of 4 years duration, 75% of patients had radioscaphoid changes, and for those of 9 years duration 60% of the patients had midcarpal changes. The pattern of arthritis in scaphoid nonunion is that of scapholunate advanced collapse (SLAC) wrist resulting from rotary subluxation of the distal scaphoid fragment. The radius-proximal scaphoid fragment joint and the radiolunate joint were consistently spared from degenerative changes, even with severe arthritis. Instability was progressive and associated with an earlier onset of arthritis. Patients with symptomatic scaphoid nonunions appear to have a significant likelihood of arthritis developing.

Experiences in the use of eight cutaneous and osteocutaneous superficial and deep circumflex iliac free flaps.

Eight patients underwent free tissue transfers involving groin cutaneous or osteocutaneous flaps using the superficial and deep circumflex iliac arteries and veins. Four were used for head and neck reconstruction, two for severe neck scar contractures, and two for composite skin and mandibular reconstruction. Three were used in lower extremity reconstructions, all in situations requiring bone and skin reconstruction. One was used for skin cover alone in an upper extremity reconstruction for wrist cover. One of the head and neck cases sustained vascular thrombosis requiring a second successful free flap coverage for a 12.5% failure rate. One required re-exploration with successful salvage. The average operating time was 12 hours. The anatomy and surgical techniques are discussed. The main values of the procedure are the presence of a double vascular supply of both arteries and veins for complex reconstructions, and the fact that a large area of skin and subcutaneous tissue can be procured, with a relatively inconspicuous donor site.

The giant apocrine hidrocystoma.

We report a patient with a large apocrine hidrocystoma. These tumors are almost always under 10 mm in diameter. In this 40-year-old man the tumor measured 20 mm. Apocrine hidrocystoma must be considered when evaluating a patient with a large cystic lesion of the face. Surgical management is similar to that of other benign cystic lesions of this region.