Can I handle the scalpel?:Different views on critical subtask assessment between residents and expert surgeons

Background: Success of surgical procedures largely depends on good judgment and decision making and these skills are mostly taught implicitly in the OR. Cognitive task analysis (CTA) has been used successful to elicit tacit expert knowledge to determine the decision points in a medical procedure and then use this in medical skill instructions. For instructions to be effective, it is also important that they are timed properly, that is, during low mental workload in the resident. Aim(s): As a start for further research, we therefore asked residents to indicate their mental workload during the steps of an orthopaedic procedure. Because in the OR, residents are commonly guided by supervisors, we also investigated which steps supervisors find mentally demanding. Methods: A task analysis of a total hip replacement procedure was constructed. Subsequently we asked both 17 orthopedic surgeons (supervisors) and 21 residents to rate (5-point scale) how much mental effort they invest in each subtask. They were asked to explain ratings above average (>3). Results: Although there were subtasks where supervisors and residents disagreed on the level of attention required, overall, supervisors and residents agreed for most subtasks. High attention was related to subtasks that require decision making skills. However, the reasons were different. In residents, high ratings were associated with subtasks that they found difficult, or where they were anxious about doing it accurately. Supervisors’ ratings were more correlated with the evaluation of crucial, i.e., point-of-no-return steps where quality of execution has important consequences for later steps, end result or complications. Discussion/Conclusion: Supervisors pay more attention to steps that will become important later in the procedure, whereas residents are more anxious about their own performance in crucial steps. It may be useful for supervisors and residents to be aware of this difference in interpretation of “important steps”

Adherence to and effectiveness of an individually tailored home-based exercise program for frail older adults, driven by mobility monitoring:design of a prospective cohort study

Background: With the number of older adults in society rising, frailty becomes an increasingly prevalent health condition. Regular physical activity can prevent functional decline and reduce frailty symptoms. In particular, home-based exercise programs can be beneficial in reducing frailty of older adults and fall risk, and in improving associated physiological parameters. However, adherence to home-based exercise programs is generally low among older adults. Current developments in technology can assist in enlarging adherence to home-based exercise programs. This paper presents the rationale and design of a study evaluating the adherence to and effectiveness of an individually tailored, home-based physical activity program for frail older adults driven by mobility monitoring through a necklace-worn physical activity sensor and remote feedback using a tablet PC. Methods/design: Fifty transitionally frail community-dwelling older adults will join a 6-month home-based physical activity program in which exercises are provided in the form of exercise videos on a tablet PC and daily activity is monitored by means of a necklace-worn motion sensor. Participants exercise 5 times a week. Exercises are built up in levels and are individually tailored in consultation with a coach through weekly telephone contact. Discussion: The physical activity program driven by mobility monitoring through a necklace-worn sensor and remote feedback using a tablet PC is an innovative method for physical activity stimulation in frail older adults. We hypothesize that, if participants are sufficiently adherent, the program will result in higher daily physical activity and higher strength and balance assessed by physical tests compared to baseline. If adherence to and effectiveness of the program is considered sufficient, the next step would be to evaluate the effectiveness with a randomised controlled trial. The knowledge gained in this study can be used to develop and fine-tune the application of innovative technology in home-based exercise programs

The role of small-colony variants in failure to diagnose and treat biofilm infections in orthopedics

Biomaterial-related infection of joint replacements is the second most common cause of implant failure, with serious consequences. Chronically infected replacements cannot be treated without removal of the implant, as the bio film mode of growth protects the bacteria against antibiotics. This review discusses bio film formation on joint replacements and the important clinical phenomenon of small-colony variants (SCVs). These slow-growing phenotypic variants often remain undetected or are misdiagnosed using hospital microbiological analyses due to their unusual morphological appearance and biochemical reactions. In addition, SCVs make the infection difficult to eradicate. They often lead to recurrence since they respond poorly to standard antibiotic treatment and can sometimes survive intracellularly

The influence of computer-assisted surgery on rotational, coronal and sagittal alignment in revision total knee arthroplasty

BACKGROUND: Despite good results of primary total knee arthroplasty (TKA), the number of revision total knee arthroplasties (rTKAs) is rising. Proper implant position is essential, since malposition leads to worse clinical outcome. In rTKA most anatomical landmarks have disappeared because of extensive bone loss, making it more difficult to adequately implant the knee prosthesis. In primary TKA, computer-assisted surgery (CAS) leads to better prosthetic alignment than mechanical navigation guides. Literature about the use of CAS in rTKA is scarce though, and the effect on rotational prosthetic alignment has not been investigated yet. Hence the primary objective of this study is to compare rotational prosthetic alignment when using CAS in rTKA compared to a mechanical navigation guide. Secondary objectives are to compare prosthetic alignment in the coronal and sagittal planes. It is hypothesized that CAS leads to better rotational, coronal and sagittal prosthetic alignment when used during rTKA. METHODS/DESIGN: A prospective clinical intervention study with use of a historical control group will be conducted. Forty-four patients with a minimum age of 18 to be admitted for CAS-rTKA between September 2012 and September 2015 will be included in the intervention group. Forty-four patients with a minimum age of 18 who underwent rTKA with the use of a mechanical navigation guide between January 2002 and April 2012 will form the historical control group. Both groups will be matched according to gender and type of revision prosthesis. Rotational prosthesis alignment will be evaluated using a CT-scan of the knee joint. DISCUSSION: Proper implant position is essential, since malposition leads to worse clinical outcome. Several studies show a significantly positive influence of CAS on prosthetic alignment in primary TKA, but literature about the use of CAS in rTKA is limited. The purpose of this study is thus to investigate the influence of CAS during rTKA on postoperative prosthetic alignment, compared to mechanical navigation guides. TRIAL REGISTRATION: Netherlands National Trial Register NTR351