Robotic control in knee joint replacement surgery

A brief history of robotic systems in knee arthroplasty is provided. The place of autonomous robots is then discussed and compared to more recent 'hands-on' robotic systems that can be more cost effective. The case is made for robotic systems to have a clear justification, with improved benefits compared to those from cheaper navigation systems. A number of more recent, smaller, robot systems for knee arthroplasty are also described. A specific example is given of an active constraint medical robot, the ACROBOT system, used in a prospective randomized controlled trial of unicondylar robotic knee arthroplasty in which the robot was compared to conventional surgery. The results of the trial are presented together with a discussion of the need for measures of accuracy to be introduced so that the efficacy of the robotic surgery can be immediately identified, rather than have to wait for a number of years before long-term clinical improvements can be demonstrated.     

Confidential Incident Reporting on the UK Railways: The ‘CIRAS’ System

The paper describes CIRAS (Confidential Incident Reporting and Analysis System), a confidential reporting system developed by the authors in collaboration with ScotRail, the Health and Safety Executive, Railtrack and the (now defunct) British Rail Board. After a two-year pilot/developmental study with ScotRail during 1995–97, the system is now subscribed to by all but one of the major train operating companies, rail infrastructure and maintenance companies with a presence in Scotland; plus a developing profile in the rest of the UK.  CIRAS gathers data in three ways: (i) from an initial report form or telephone call, (ii) from a structured follow-up telephone questionnaire, and (iii) from an in-depth interview with a researcher (telephone or face-to-face, according to priority). The interviews bring to light details of personal motive, and of intended/unintended actions, which are not commonly found on company-run databases because of their association with disciplinary procedures. Information is processed through a human factors model and fed back to the companies involved, in disidentified form, to take corrective action.  The basic structure of the human-factors model is described; data are presented on reports received to date which have been processed through this model. The system has recently been recommended by a UK Parliamentary Committee and by Railtrack Safety and Standards Directorate for extension to the UK network as a whole.     

A cluster separation measure

A measure is presented which indicates the similarity of clusters which are assumed to have a data density which is a decreasing function of distance from a vector characteristic of the cluster. The measure can be used to infer the appropriateness of data partitions and can therefore be used to compare relative appropriateness of various divisions of the data. The measure does not depend on either the number of clusters analyzed nor the method of partitioning of the data and can be used to guide a cluster seeking algorithm.     

Fibrous myopathy. A rheumatic complication of drug abuse

A progressive fibrous myopathy may result from chronic intramuscular drug abuse. This complication may mimic other rheumatic disorders and early recognition may prevent disability. The patient described here presented with fixed flexion and extension contracture of hips and knees, respectively, after abusing meperidine and other agents for 3 years. Soft tissues of thighs and buttocks were "wood hard," EMG showed absence of action potentials in affected muscles, and biopsy revealed extensive replacement of muscle with dense, acellular fibrous tissue. Possible mechanisms are discussed.     

The electron probe microanalysis of electrical discharge machined die surfaces

The elemental concentration and distribution characteristics of electrical discharge machined die surfaces have been investigated to a depth of 150 m using the techniques of electron microprobe analysis. General results indicate a correlation between elemental concentration changes such as Carbon gradiant and Manganese distribution, and other spark eroded surface characteristics previously determined by more conventional metallurgical techniques.     

Preoperative radiotherapy for adenocarcinoma of the rectosigmoid

Ninety-seven patients with adenocarcinoma of the rectosigmoid have been treated with high dose (5000-6000 rad) preoperative irradiation from 1960 through 1972 at the University of Oregon Health Sciences Center. Fifty-seven were initially clinically resectable and 40 were initially inoperable. Forty of the 57 initially clinically resectable patients had "curative" resections and are at risk for more than 5 years. An increase in 5-year survival (from 38% to 53%) and an absence of pelvic recurrence have occurred in those patients receiving preoperative irradiation and "curative" resection. Four of the 40 initially inoperable patients are alive without tumor. Three of the four survivors had irradiation and surgery; one had irradiation only. An additional four patients had no evidence of tumor at death. Tumor was totally sterilized by irradiation and nine patients and reduced to microfocal extent in an additional three of the 97 patients. Incidence of complications was no greater than has been reported in a surgical series from the same institution.     

Sustainable Disposal of Domestic Sanitary Waste

The study presented is an example of the assessment of the relative sustainability of either option for disposal of domestic sanitary waste, either via the toilet or via the solid waste route. This required an evaluation of the total (social, economic, environmental, and technical) benefit/cost of implementing and adopting the alternative routes and an assessment of public responsiveness to encouragement to change sanitary waste disposal practices. It illustrates how, even for an apparently straightforward either/or question, the assessment of relative sustainability is complex and the amount of data needed to quantify sustainability indicators is prodigious. The study also provides an appraisal of the effectiveness of public campaigns to reduce waterborne disposal. Important information regarding public attitude and behavior in relation to wastewater systems has been acquired and lessons for ways of encouraging behavioral change to more sustainable ways of living have been gleaned.