Total ankle replacement. Early experiences with STAR prosthesis.

Early designs of Total Ankle Replacement (TAR) had a high failure rate. More recent experience with the 3-piece, meniscal bearing, total ankle replacement has been more promising. We report a review of the early results of our first 22 prostheses in 20 patients undergoing Scandinavian Total Ankle Replacement (STAR) in Northern Ireland. There was a mean follow-up time of 26 months. Seventeen patients are pain-free at the ankle joint during normal daily activities. Two of the early cases have required revision surgery due to technical errors. Other complications have included malleolar fractures, poor wound healing and postoperative stiffness. These early results show high levels of patient satisfaction, and we are encouraged to continue with total ankle arthroplasty. There is a steep initial learning curve and use of TAR should be restricted to foot and ankle surgeons.

Fractured lateral epicondyle with associated elbow dislocation.

We describe a case series involving a very unusual injury in children, i.e. a Milch 1 fracture of the lateral condyle with an associated dislocation of the elbow. This fracture configuration is normally stable as the intact capitellotrochlear groove serves as a lateral buttress for the coronoid-olecranon ridge of the ulna. In this series, however, each patient had an associated dislocation. These injuries usually present as a clinical dislocation and if the elbow is manipulated before radiographic imaging, the fracture line can be difficult to see on the post-reduction films. We recommend that all patients with a dislocated elbow should have elbow stability assessed under general anaesthesia, because a missed lateral condylar injury can lead to abnormalities in carrying angle, epiphyseolysis or an unstable elbow.

Iron-superoxide dismutase expression in transgenic alfalfa increases winter survival without a detectable increase in photosynthetic oxidative stress tolerance.

To determine whether overexpression of Fe-superoxide (SOD) dismutase would increase superoxide-scavenging capacity and thereby improve the winter survival of transgenic alfalfa (Medicago sativa L.) plants, two genotypes were transformed with the vector pEXSOD10, which contains a cDNA for Arabidopsis Fe-SOD with a chloroplast transit peptide and cauliflower mosaic virus 35S promoter. A novel Fe-SOD was detected by native PAGE in both greenhouse- and field-grown transgenic plants, but activity varied among independent transgenic plants. The increased Fe-SOD activity was associated with increased winter survival over 2 years in field trials, but not with oxidative stress tolerance as measured by resistance of leaves to methyl viologen, a superoxide generator. Total shoot dry matter production over 2 harvest years was not associated with Fe-SOD activity. There was no detectable difference in the pattern of primary freezing injury, as shown by vital staining, nor was there additional accumulation of carbohydrates in field-acclimated roots of the transgenic alfalfa plants. We did not detect any difference in growth of one transgenic plant with high Fe-SOD activity compared with a non-transgenic control. Therefore, the improvement in winter survival did not appear to be a consequence of improved oxidative stress tolerance associated with photosynthesis, nor was it a consequence of a change in primary freezing injury. We suggest that Fe-SOD overexpression reduced secondary injury symptoms and thereby enhanced recovery from stresses experienced during winter.

Assessment of technical skills transfer from the bench training model to the human model.

BACKGROUND: This study examines whether technical skills learned on a bench model are transferable to the human cadaver model. METHODS: Twenty-three first-year residents were randomly assigned to three groups receiving teaching on six procedures. For each procedure, one group received training on a cadaver model, one received training on a bench model, and one learned independently from a prepared text. Following training, all residents were assessed on their ability to perform the six procedures. RESULTS: Repeated measures analysis of variance revealed a significant effect of training modality for both checklist scores (F(2,44) = 3.49, P <0.05) and global scores (F(2,44) = 7.48, P <0.01). Post-hoc tests indicated that both bench and cadaver training were superior to text learning and that bench and cadaver training were equivalent. CONCLUSIONS: Training on a bench model transfers well to the human model, suggesting strong potential for transfer to the operating room.

Objective structured assessment of technical skill (OSATS) for surgical residents.

BACKGROUND: The technical skill of surgical trainees is not well assessed. This study aimed (1) to compare the reliability of three scoring systems, (2) to compare live and bench formats and (3) to assess construct validity of a test of operative skill. METHODS: Parallel examinations of operative skill, one using live animals and one using simulations, were developed. Performance was graded using operation-specific checklists, detailed global rating forms and pass/fail judgements. Twenty surgical residents each took both formats. RESULTS: Disattenuated correlations between live and bench scores were high (0.69-0.72). Mean interrater reliability across stations ranged from 0.64 to 0.72. Internal consistency was moderate to high (alpha: 0.61-0.74) for the live format using the checklist and for live and bench formats using global ratings. Global ratings discriminated between resident levels for both formats (bench: F(2,17) = 4.45, P < 0.05; live: F(2,17) = 3.55, P < 0.05), checklists did not. CONCLUSION: This preliminary study suggests that the Objective Structured Assessment of Technical Skill can reliably and validly assess surgical skills. Global ratings are a better method of assessment than task-specific checklists. Bench model simulation gives equivalent results to use of live animals for this test format.

Applying a relative ranking model to the self-assessment of extended performances.

BACKGROUND: Accurate self-assessment is an important but underdeveloped skill in medicine that, in the past, has received little formal attention from educators. METHOD: Following an orthopedic rotation, twenty-five orthopedic surgery residents performed a self-assessment task for ten skills using a new relative ranking method, in which an individual's skills are ranked relative to each other rather than being compared to the individual's peers. Supervising faculty assessed residents using the same instrument. Faculty inter-rater reliability was measured and comparisons were made between each resident's self-assessment and the faculty assessments using Spearman rank order correlation coefficients. RESULTS: The mean correlation between faculty rating the same resident was 0.27 (sd = 0.49). The mean correlation between resident and faculty rankings was 0.20 (sd = 0.38), but was higher for junior residents (0.33) than for senior residents (0.12), apparently because senior residents do not alter their self-assessments while faculty change their assessments of senior residents. CONCLUSIONS: Consistent with the literature in other fields, we find that self-assessment is poor among surgical trainees when they are asked to assess their own performance over an extended time period.

Topics and skills in orthopaedics for the general practitioner.

We conducted a survey to identify topics and skills in orthopaedics that should be included in a curriculum for the education of general practitioners. Forty-one program chairpersons responded to a questionnaire that asked respondents to rate the importance of each of eighty topics or skills related to orthopaedic surgery. The questionnaires were analyzed with use of descriptive statistics. The stability of the results was assessed with a follow-up questionnaire five months after the first survey had been completed, and the results were analyzed with a correlation coefficient of the mean ratings of importance and percentage agreement on individual items. The results produced a rank-order listing of important topics and skills in orthopaedics for the general practitioner. The topics and skills that were rated highly by program chairpersons corresponded to the types of musculoskeletal problems most commonly seen by family practitioners. This survey provides concurrent validity for the rank-order lists and confirms the need to include these items in a core curriculum for general practitioners.

A comparative analysis of the costs of administration of an OSCE (objective structured clinical examination).

BACKGROUND: The objective structured clinical examination (OSCE) has become an accepted technique for the evaluation of clinical competence in medicine. Although advances have been made in our knowledge of the psychometric aspects of the OSCE, extremely little has been written about feasibility and cost issues. Given the current economic imperative to control costs and the extremely scant literature on the costs of developing and administering an examination in medicine, the authors felt it timely and relevant to explore issues related to the cost of the OSCE. METHOD: In 1991-92 and in 1992-93, costs and time requirements to implement and administer a structured oral (SO) examination and a six-station OSCE for a surgical clerkship at the University of Toronto Faculty of Medicine were gathered by review of invoices, interviews with those involved, and perusal of diaries kept by staff. RESULTS: To develop and administer the six-station OSCE, 327.5 hours of staff and faculty time were required for each rotation of surgical clerks (8.2 hours per student). The SO examination required 110 hours of staff and faculty time (2.75 hours per student). Direct expenses for the OSCE amounted to U.S. $6.90 per student per station, compared with no direct expense for the SO examination. CONCLUSION: The OSCE was more time-consuming and more expensive in human and material costs than the SO examination. However, costs of the OSCE can be substantially reduced from approximately U.S. $35 to U.S. ! per student per station if test developers, standardized patients, support staff, and examiners can donate their time. The authors compare the costs and time requirements of their OSCE with those of other OSCEs reported in the literature, and they provide guidelines to assist educators in deciding whether the costs of an OSCE are justifiable in the educators' individual settings.

Collagen type III in rotator cuff tears: An immunohistochemical study.

The presence and distribution of collagen type III, which represents newly formed fibers of early repair, were investigated in four surgically removed en bloc specimens of complete rotator cuff tears. The patients were two men and two women who ranged in age from 63 to 71 years. They had received preoperative, conservative treatment for a period varying from 3 months to 3 years. For the identification of the collagen immunohistochemical staining was performed by the peroxidase-antiperoxidase method with the use of monoclonal antibody against human collagen type III. Collagen type III was discernible throughout the tendon proper in all specimens. It often occurred in association with proliferating fibroblastic cells. Collagen type III was abundant only in the perivascular spaces of the much thickened bursal wall that extended over the margins of the tear. We concluded that the presence of collagen type III indicates the need for a continued attempt for repair at the site of the tear, including both bursal and tendinous tissues.

Adhesive capsulitis of the shoulder: current concepts and treatment.

Primary adhesive capsulitis of the shoulder is a common cause of a painful shoulder in clinical practice. The pathogenesis remains unclear. Many patients continue to have significant long-term restrictions in their range of motion although few are functionally restricted. Prevention is the ideal treatment. Patients respond to treatment plans directed at pain relief and improving the range of motion, however, ongoing controlled therapeutic trials are necessary to better refine the selection of treatment for individual patients.

The effect of cigarette smoking on the long term success rates of aortofemoral and femoropopliteal reconstructions.

Cigarette smoking is a recognized causative factor in the genesis of arterial insufficiency, but the precise effect of nonsmoking on the success of the operation is not well documented. Three hundred and twenty-six patients who underwent aortobifemoral bypass (209) or femoropopliteal bypass (117) between 1969 and 1978 were observed to determine whether or not the discontinuation of cigarette smoking affected the long term results of these grafts. Patients were divided into three groups: group 1 smoked preoperatively and postoperatively; group 2 smoked preoperatively but not postoperatively, and group 3 did not smoke at all. The five year cumulative success rates for aortobifemoral bypass in the groups were: 42 per cent for group 1 (130 patients); 77 per cent for group 2 (67 patients), and 71 per cent for group 3 (12 patients) (p less than 0.001). In the femoropopliteal group, the variation with regard to the known patency rates of autogenous and prosthetic grafts made the results more difficult to assess. For all grafts the five year cumulative success rates were: 38 per cent of group 1 (57 patients); 33 per cent for group 2 (40 patients), and 70 per cent for group 3 (20 patients) (p less than 0.001). Subdivision of groups 1 and 2 into autogenous and synthetic grafts gave identical success rates of 54 per cent for long saphenous vein grafts (66). Prosthetic grafts were successful at five years in 19 per cent of the patients in group 1 (16 patients) and 43 per cent in group 2 (15 patients). These results were not significant. These results clearly favor the postoperative nonsmoker over the smoker in the aortofemoral group but the distinction in the femoropopliteal group is less clear, although there is a similar trend.

Clinical application of basic research on continuous passive motion for disorders and injuries of synovial joints: a preliminary report of a feasibility study.

Since 1970, when the concept of continuous passive motion (CPM) was originated by one of the authors (R.B.S.), he and a succession of his research fellows have investigated its biological effects on the healing and regeneration of articular tissues in a wide variety of experimental models in rabbits. From this basic research he concluded that CPM is well tolerated, seems to be painless, stimulates the healing and regeneration of articular tissues, prevents joint stiffness, and permits the normal healing of arthrotomy incisions. Beginning in 1975, one of the authors (H.W.H.), and in 1978, the remaining authors, (from two additional Canadian cities) applied the knowledge from the basic research on CPM to the orthopaedic care of human patients. The CPM devices for humans (CPM Mobilimbs), which have been designed in collaboration with University of Toronto engineers, include, to date, devices for the ankle-knee-hip, the elbow, and the finger. Indications for CPM in patients have been the immediate postoperative management following such operative procedures as open reduction and internal fixation of fractures, arthrotomy and arthrolysis for post-traumatic arthritis, synovectomy, surgical drainage for septic arthritis, release of extraarticular contractures, metaphyseal osteotomies, total joint replacement, and ligamentous reconstruction. The case reports of nine selected patients are presented as examples of the clinical application of CPM. These patients have been relatively free of pain, have maintained the increased motion gained at operation, and have accepted the application of CPM well. There have been no complications of CPM; the operative wounds have healed well and the period of hospitalization has not been prolonged. The authors believe that the clinical application of CPM is feasible and that the clinical and radiographic results of CPM in these patients are encouraging. Long-term, prospective clinical investigations (including control patients in whom CPM is not used) will be required to assess the efficacy of CPM in relation to the various stated indications.

Health indicators and information systems for the year 2000.

PIP: Report focus is on the general problem of designing and developing information systems equal to the task of promoting and monitoring "Health for All by the Year 2000." Attempting to bridge the gap between theory and practice, this 2-part report proposes some priorities and guidelines for organizing and focusing the efforts of the many agencies, groups, and individuals working on health statistics worldwide; and concentrates on the situation in less developed countries where health information networks in support of the decision making process continue to be very weak and their content and organization need reappraisal. An illustrative set of health indicators for national health planning in a developing country is used to take stock of available concepts of measurement, to test their relevance and feasibility, and to consider the steps necessary to translate these concepts into operational health information systems. There are numerous advantages in concentrating on what are commonly termed "health indicators" and using them as a point of departure for collecting data and building information networks. Indicators define the content of data systems, a step that should logically precede decisions regarding data series, methods, staffing, and organizations. If properly designed to reflect the primary objectives of national or community health policy, a set of indicators serves as the minimum specifications of the information support system and describes its overall task. Health indicators are also an excellent way to promote statistical comparability within and among health care systems. Health indicators in the model presented are defined as statistics selected from the larger pool because they have the power to summarize, to represent a larger body of statistics, or to serve as indirect or proxy measures for information that is lacking. It would be both self-defeating and contrary to World Health Organization (WHO) goals to adopt a narrow perspective on health indicators and information systems. Those working on health indicators need to be in close touch with developments in the social indicators field. The following are among the major points made in the review and evaluation of some of the concepts and methods available to developing countries in designing health information systems for the year 2000: utility of proposed indicators, primarily for planning, monitoring, and evaluation at the national level, but also to some extent at the community level; state of readiness; validity, reliability, specificity, sensitivity, and economy or efficiency of proposed measures; feasibility, i.e., have practical and affordable methods of data acquisition been demonstrated; basic subcategories and disaggregations; compatibility with socioeconomic concerns and indicators; comparability with concepts of measurement used in more developed countries; and principal areas in need of further research and development.^ieng

Uniform basic data sets for health statistical systems.

The United States approach to coordinating health statistics involves introduction of multipurpose basic data sets describing health status and the health care system. Standard reporting procedures have been used for many years for vital statistics. Recently designated data sets cover health manpower, inpatient facilities, short-stay hospital discharges, and use of ambulatory care services. A data set for long-term health care is in the design stage. Advantages of this approach in the United States and internationally are: basic comparisons can be made between health care settings are geographic areas while maintaining the variety and flexibility of existing public and private information systems; shared local, regional, and national data systems can be set up; and better coordination can be achieved between government-sponsored general-purpose and administrative data systems. Problem areas are: avoiding undue proliferation, e.g. of disease-specific data sets; adhering to the principle of minimal requirements; linking data sets and coordinating them with census and other social indicators; promoting widespread use; assuring data quality; establishing mechanisms for review and revision; and extending the concept internationally.

The holding power of orthopedic screws in vivo.

Great difficulty is encountered in choosing screws for internal fixation, for screws differ in material, geometry, dimension, and in insertion technique. Recently claims have been made that self-tapping screws cause necrosis of bone and result in fibrous tissue formation, with loss of holding power. This investigation was undertaken to study the healing of bone about screws inserted for a period of 3 months. Self tapping and non-self tapping screws were employed. The Vitallium screws not only differed in dimension, but also in configuration of the thread, with the smaller of the self-tapping screws exhibiting a "V" thread in distinction to the buttress thread of the larger screw. The histologic data were correlated with the holding power of the screws as obtained by means of a push out test, performed with the aid of an Instrom testing machine. The largest screw tested, the 4.5 mm non-self tapping stainless steel AO screw (Type 1), provided the greatest safety factor to push out loading over the period tested in the unloaded system. The self tapping and non-self tapping screws of similar material and size were found to maintain comparable holding power at all intervals tested in vivo in the unloaded system. No histological differentiation could be made with regard to both death or tissue reaction around the implant, between the stainless steel or cobalt chromium alloy materials, nor between the self tapping and non-self tapping insertion methods.