Estimation of the forces generated by the thigh muscles for transtibial amputee gait.

The forces generated by the muscles with origin on the human femur play a major role in transtibial amputee gait, as they are the most effective of the means that the body can use for propulsion. By estimating the forces generated by the thigh muscles of transtibial amputees, and comparing them to the forces generated by the thigh muscles of normal subjects, it is possible to better estimate the energy output needed from prosthetic devices. The purpose of this paper is to obtain the forces generated by the thigh muscles of transtibial amputees and compare these with forces obtained from the same muscles in the case of normal subjects. Two transtibial amputees and four normal subjects similar in size to the amputees were investigated. Level ground walking was chosen as the movement to be studied, since it is a common activity that most amputees engage in. Inverse dynamics and a muscle recruitment algorithm (developed by AnyBody Technology(®)) were used for generating the muscle activation patterns and for computing the muscle forces. The muscle forces were estimated as two sums: one for all posterior muscles and one for the anterior muscles, based on the position of the muscles of the thigh relative to the frontal plane of the human body. The results showed that a significantly higher force is generated by the posterior muscles of the amputees during walking, leading to a general increase of the metabolic cost necessary for one step.

Magnetic resonance spectroscopy of the brain: review of metabolites and clinical applications.

Magnetic resonance imaging (MRI) provides anatomic images and morphometric characterization of disease, whereas magnetic resonance spectroscopy (MRS) provides metabolite/biochemical information about tissues non-invasively in vivo. MRS has been used clinically for more than two decades. The major applications of this advanced MRI tool are in the investigation of neurological and neurosurgical disorders. MRS has also been used in the evaluation of the prostate gland and muscle tissue, but these applications will not be addressed in this review. The aim of this review is to attempt to introduce the technique, review the metabolites and literature, as well as briefly describe our clinical experience.

Clinicopathologic features of breast disease in Jamaica: findings of the Jamaican Breast Disease Study, 2000-2002.

OBJECTIVE: To describe the clinicopathologic profile of breast disease in Jamaica. METHODS: The Jamaican Breast Disease Study is an ongoing prospective, multidisciplinary investigation of breast disease at the University Hospital of the West Indies (UHWI). The initial phase was a prevalence survey comprising all consenting patients referred to the Surgical Outpatient Department (SOPD) UHWI, for breast disease. Demographic, clinical, radiologic and pathologic information were recorded for each patient and the data for the first three years (2000-2002) were analyzed. RESULTS: A total of 1189 patients was enrolled for the study period (28.8% of all new SOPD patients). The age range was 10 to 93 years (mean/SD = 36.5 +/- 16.4 years) with a female : male ratio of 14:1. Most patients (67.8%) presented with a palpable lump and the clinical diagnosis was benign in the majority (70.4%) of patients. Fibroadenoma was the most common benign histologic result (39.4% of all biopsies) followed by non-proliferative (fibrocystic) disease (19.3% of all biopsies). Proliferative disease without atypia, complex fibroadenoma and atypical ductal hyperplasia accounted for 6.9%, 2.6% and 0.4% of biopsies respectively. Overall, 23.4% of biopsies showed malignant histology (10.8% patients); invasive ductal carcinoma accounted for the majority of these cases (69.5%). CONCLUSIONS: The majority of patients with breast disease in Jamaica are young women with clinically benign disease. There was a low prevalence of clinically significant premalignant disease. This is the first study to prospectively describe the clinicopathologic features of breast disease in Jamaica and supports the need for advocating breast cancer screening to facilitate detection of significant premalignant disease and early stages of breast cancer.

Ionizing radiation. The question of responsible use: Pandora's box revisited.

For over one hundred years, ionizing radiation has assisted in medical diagnostics. Recently, there have been reports of radiation injury in patients undergoing fluoroscopic procedures. It is time to review some of the risks of ionizing radiation as well as some of our practices at the University Hospital of West Indies (UHWI). In this review, we discuss the relative risks associated with common radiological examinations as well as explore the relative merits of various clinical protocols for the radiological investigation of common diseases seen at the UHWI.

Ionizing radiation. The question of responsible use: Pandora's box revisited

For over one hundred years, ionizing radiation has assisted in medical diagnostics. Recently, there have been reports of radiation injury in patients undergoing fluoroscopic procedures. It is time to review some of the risks of ionizing radiation as well as some of our practices at the University Hospital of West Indies (UHWI). In this review, we discuss the relative risks associated with common radiological examinations as well as explore the relative merits of various clinical protocols for the radiological investigation of common diseases seen at the UHWI

Quality assurance standards for purchasing and inventory control.

A process is described for quality assurance in pharmaceutical purchasing and inventory control. A quality assurance program should ensure that quality drugs are purchased at the lowest price, drug products are available when needed, the system is managed efficiently, internal controls are provided, drug products are stored under appropriate conditions, and laws, regulations, accreditation standards, and procedures are followed. To meet these objectives, product quality, vendor performance, the department's system of internal controls, purchasing data, and storage conditions should be monitored. A checklist for evaluating purchasing and inventory practices and a sample audit form listing quality assurance criteria, standards, procedures, and recommended actions are provided. A quality assurance program for pharmaceutical purchasing and inventory control should define institution-specific criteria and standards and use these standards for continual evaluation of all aspects of the purchasing and inventory control system. Documentation of quality assurance activities should be provided for use by the purchasing department, hospital administration, and regulatory bodies.