Correlation between patella and patellar tendon width: An anatomic study.

Anterior cruciate ligament (ACL) rupture is a common injury among orthopaedic patients with many different treatment modalities including bone-patella-bone autograft (BPBA) ACL reconstruction. Patella tendon width has been reported to be a predictor of recovery speed and success following BPBA repair. This study reports on the strength of the relationship between patella width and patella tendon width. Twenty fresh frozen cadavers were included in the study. Patella and patellar tendon measurements were recorded at the midpoint of the patellar tendon. Pearson correlation and linear regression were used to determine the relationship between patella width and patellar tendon width. Bivariate correlations with 95% confidence intervals and coefficients of determination (R(2) ) are reported. The study used 20 cadavers, 12 men and 8 women with a mean age of 72 (standard deviation [SD] = 12; range = 44 to 87). The mean patella width was 49.24mm (SD = 4.11; range 42.33mm-56.33mm) while the mean patellar tendon width was 26.10mm (SD = 3.31; range 18.33mm-33.33mm). The correlation between patella width and patellar tendon width was 0.67 (95% confidence interval = 0.45 - 0.81). R(2), the percent of variance in patellar tendon width accounted for by patella width, was 0.45. The regression equation for predicting patellar tendon width (y) yielded a formula of y = 0.536 + -0.316 × patella width. A moderate correlation exists between patella width and patellar tendon width. Our data suggests that this correlation is strongest with wider patellas and is more loosely associated with smaller patellas.

Surgical approach significantly affects the complication rates associated with total hip arthroplasty.

AIMS: A variety of surgical approaches are used for total hip arthroplasty (THA), all with reported advantages and disadvantages. A number of common complications can occur following THA regardless of the approach used. The purpose of this study was to compare five commonly used surgical approaches with respect to the incidence of surgery-related complications. PATIENTS AND METHODS: The electronic medical records of all patients who underwent primary elective THA at a single large-volume arthroplasty centre, between 2011 and 2016, with at least two years of follow-up, were reviewed. After exclusion, 3574 consecutive patients were included in the study. There were 1571 men (44.0%) and 2003 women (56.0%). Their mean age and body mass index (BMI) was 63.0 years (sd 11.8) and 29.1 kg/m2 (sd 6.1), respectively. Data gathered included the age of the patient, BMI, the American Society of Anesthesiologists (ASA) score, estimated blood loss (EBL), length of stay (LOS), operating time, the presence of intra- or postoperative complications, type of complication, and the surgical approach. The approaches used during the study were posterior, anterior, direct lateral, anterolateral, and the northern approach. The complications that were recorded included prolonged wound drainage without infection, superficial infection, deep infection, dislocation, aseptic loosening, and periprosthetic fracture. Finally, the need for re-operation was recorded. Means were compared using analysis of variance (ANOVA) and Student's t-tests where appropriate and proportions were compared using the chi-squared test. RESULTS: A total of 248 patients had 263 complications related to the surgery, with an incidence of 6.94%. The anterior approach had the highest incidence of complications (8.5% (113/1329)) and the posterior approach had the lowest, at 5.85% (97/1657; p = 0.006). Most complications were due to deep infection (22.8%), periprosthetic fracture (22.4%), and prolonged wound drainage (21.3%). The rate of dislocation was 0.84% (14/1657) with the posterior approach and 1.28% (17/1329) with the anterior approach (p = 0.32). CONCLUSION: Overall, THA has a relatively low complication rate. However, the surgical approach plays a role in the incidence of complications. We found that the posterior approach had a significantly lower overall complication rate compared with the anterior approach, with an equal dislocation rate. Periprosthetic fracture and surgical site infection contributed most to the early complication rates. Cite this article: Bone Joint J 2019;101-B:646-651.

Interventions to improve risk communication in clinical genetics: systematic review.

OBJECTIVE: Effective risk communication may enable clients to participate effectively in decision-making about their health and health care. A systematic review of existing literature on risk communication in genetics, and its effects on key outcomes for clients, was undertaken. METHOD: Systematic searching of six electronic databases and data extraction from included studies; narrative synthesis of results. RESULTS: Twenty-eight studies were included, principally from cancer genetics. Sixteen communication interventions have been evaluated, generally showing improvements in cognitive outcomes for users, such as knowledge, understanding and risk perception, and without adverse effects on anxiety, cancer-related worry and depression. However, often it was the supportive or emotional elements of counselling that provided benefits to users, rather than the informational or educational elements. Similar results were found in 12 further studies of decision aids which also appear to achieve shorter consultations that can focus more on the supportive elements of counselling. CONCLUSION: For both communication models and decision aids, the supportive or emotional elements of counselling provided more benefits to users than the informational or educational elements. PRACTICE IMPLICATIONS: Debate is required on how to strike a balance between the medical model, its agenda and perceived requirements to disclose or discuss a range of issues and the sometimes competing goals of addressing users' concerns, needs for support, issues of loss and relationship problems.

Heating and humidifying of carbon dioxide during pneumoperitoneum is not indicated: a prospective randomized trial.

BACKGROUND: Carbon dioxide (CO2) pneumoperitoneum usually is created by a compressed gas source. This exposes the patient to cool dry gas delivered at room temperature (21 degrees C) with 0% relative humidity. Various delivery methods are available for humidifying and heating CO2 gas. This study was designed to determine the effects of heating and humidifying gas for the intraabdominal environment. METHODS: For this study, 44 patients undergoing laparoscopic Roux-en-Y gastric bypass were randomly assigned to one of four arms in a prospective, randomized, single-blinded fashion: raw CO2 (group 1), heated CO2 (group 2), humidified CO2 (group 3), and heated and humidified CO2 (group 4). A commercially available CO2 heater-humidifier was used. Core temperatures, intraabdominal humidity, perioperative data, and postoperative outcomes were monitored. Peritoneal biopsies were taken in each group at the beginning and end of the case. Biopsies were subjected staining protocols designed to identify structural damage and macrophage activity. Postoperative narcotic use, pain scale scores, recovery room time, and length of hospital stay were recorded. One-way analysis of variance (ANOVA) and the nonparametric Kruskal-Wallis test were used to compare the groups. RESULTS: Demographics, volume of CO2 used, intraabdominal humidity, bladder temperatures, lens fogging, and operative times were not significantly different between the groups. Core temperatures were stable, and intraabdominal humidity measurements approached 100% for all the patients over the entire procedure. Total narcotic dosage and pain scale scores were not statistically different. Recovery room times and length of hospital stay were similar in all the groups. Only one biopsy in the heated-humidified group showed an increase in macrophage activity. CONCLUSIONS: The intraabdominal environment in terms of temperature and humidity was similar in all the groups. There was no significant difference in the intraoperative body temperatures or the postoperative variable measured. No histologic changes were identified. Heating or humidifying of CO2 is not justified for patients undergoing laparoscopic bariatric surgery.

Personalised risk communication for informed decision making about taking screening tests.

BACKGROUND: There is a trend towards greater patient involvement in healthcare decisions. Adequate discussion of the risks and benefits associated with different choices is often required if involvement is to be genuine and effective. Achieving both the adequate involvement of consumers and informed decision making are now seen as important goals for any screening programme. Personalised risk estimates have been shown to be effective methods of risk communication in general, but the effectiveness of different strategies has not previously been examined. OBJECTIVES: To assess the effects of different types of personalised risk communication for consumers making decisions about taking screening tests. SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2004), MEDLINE (1985 to December 2005), EMBASE (1985 to December 2005), CINAHL (1985 to December 2005), and PsycINFO (1989 to December 2005). Follow-up searches involved hand searching Preventive Medicine, citation searches on seven authors, and searching reference lists of articles. For the original version of this review (Edwards 2003c) we also searched CancerLit (1985 to 2001) and Science Citation Index Expanded (searched March 2002). SELECTION CRITERIA: Randomised controlled trials addressing the decision by consumers of whether or not to undergo screening, incorporating an intervention with a 'personalised risk communication element' and reporting cognitive, affective, or behavioural outcomes. A 'personalised risk communication element' is based on the individual's own risk factors for a condition (such as age or family history). It may be calculated from an individual's risk factors using formulae derived from epidemiological data, and presented as an absolute or relative risk or as a risk score, or it may be categorised into, for example, high, medium or low risk groups. It may be less detailed still, involving a listing, for example, of a consumer's risk factors as a focus for discussion and intervention. DATA COLLECTION AND ANALYSIS: Two authors independently assessed each trial for quality and extracted data. We extracted data about the nature and setting of the intervention, and relevant outcome data, along with items relating to methodological quality. We then used standard statistical methods of the Consumers and Communication Review Group to combine data using MetaView, including analysis according to different levels of detail of personalised risk communication, different condition for screening, and studies based only on high risk participants rather than people at 'average' risk. MAIN RESULTS: Twenty-two studies were included, nine of which were added in the 2006 update of this review. There was weak evidence, consistent with a small effect, that personalised risk communication (whether written, spoken or visually presented) increases uptake of screening tests (odds ratio (OR) 1.31 (random effects, 95% confidence interval (CI) 0.98 to 1.77). In three studies the interventions showed a trend towards more accurate risk perception (OR 1.65 (95% CI 0.96 to 2.81), and three other trials with heterogenous outcome measures showed improvements in knowledge with personalised risk interventions. There was little other evidence from these studies that the interventions promoted or achieved informed decision making by consumers about participation in screening. More detailed personalised risk communication may be associated with a smaller increase in uptake of tests. That is, for personalised risk communication which used and presented numerical calculations of risk, the OR for test uptake was 0.82 (95% CI 0.65 to 1.03). For risk estimates or calculations which were categorised into high, medium or low strata of risk, the OR was 1.42 (95% CI 1.07 to 1.89). For risk communication that simply listed personal risk factors the OR was 1.42 (95% CI 0.95 to 2.12). Over half of the included studies assessed interventions in the context of mammography. These studies showed similar effects to the overall dataset. The five studies examining risk communication in high risk individuals (individuals at higher risk due to, for example, a family history of breast cancer or other conditions) showed larger odds ratios for uptake of tests than the other studies (random effects OR 1.74; 95% CI 1.05 to 2.88). There were insufficient data from the included studies to report odds ratios on other key outcomes such as: intention to take tests, anxiety, satisfaction with decisions, decisional conflict, knowledge and resource use. AUTHORS' CONCLUSIONS: Personalised risk communication (as currently implemented in the included studies) may have a small effect on increasing uptake of screening tests, and there is only limited evidence that the interventions have promoted or achieved informed decision making by consumers.

Op-amp mutual inductance bridge.

A mutual inductance bridge constructed from operational amplifiers is described.