D. I. Rowley

Internal rotational error of the tibial component is a major cause of pain after total knee replacement

This study used CT analysis to determine the rotational alignment of 39 painful and 26 painless fixed-bearing total knee replacements (TKRs) from a cohort of 740 NexGen Legacy posterior-stabilised and cruciate-retaining prostheses implanted between May 1996 and August 2003. The mean rotation of the tibial component was 4.3 degrees of internal rotation (25.4 degrees internal to 13.9 degrees external rotation) in the painful group and 2.2 degrees of external rotation (8.5 degrees internal to 18.2 degrees external rotation) in the painfree group (p = 0.024). In the painful group 17 tibial components were internally rotated more than 9 degrees compared with none in the painfree group (p < 0.001). Additionally, six femoral components in the painful group were internally rotated more than 6 degrees compared with none in the painfree group (p = 0.017). External rotational errors were not found to be associated with pain. Overall, 22 (56.4%) of the painful TKRs had internal rotational errors involving the femoral, the tibial or both components. It is estimated that at least 4.6% of all our TKRs have been implanted with significant internal rotational errors.

Cognitive representations of illness and functional and affective adjustment following surgery for osteoarthritis

A prospective investigation is described which sought to test the role of illness cognitions in determining patient responses to a surgical intervention for osteoarthritis. Illness cognitions were assessed amongst a consecutive sample of patients with osteoarthritis of the knee or hip prior to undergoing joint replacement surgery. Functional activity and depression were assessed pre-operatively, and at 3 and 9 months post surgery. At pre-operative assessment, functional activity and depression were univariately associated with the perceived consequences of osteoarthritis. Path analyses using longitudinal data demonstrated that illness cognitions had predictive value in explaining outcomes. Depression at 3 months was associated with higher pre-operative perceived control beliefs suggesting that patients who have high control pre-operatively may be at risk for temporary depressed mood in the immediate aftermath of surgery. This effect was not maintained at 9 months. Depression at 9 months was lower amongst patients who were more active at 3 months, who did not attribute their condition to wear and tear and who had higher expectations of surgery. Functional activity at 9 months was higher amongst those who did not attribute their condition to growing older and who perceived more control over symptoms. Socio-demographic variables were not associated with change in functional activity or depression over the course of surgery. The results provide support for an illness cognition approach in explaining functional activity and depression outcomes following surgery.

The Knee Arthroplasty Trial (KAT) design features, baseline characteristics, and two-year functional outcomes after alternative approaches to knee replacement.

BACKGROUND The aim of continued development of total knee replacement systems has been the further improvement of the quality of life and increasing the duration of prosthetic survival. Our goal was to evaluate the effects of several design features, including metal backing of the tibial component, patellar resurfacing, and a mobile bearing between the tibial and femoral components, on the function and survival of the implant. METHODS A pragmatic, multicenter, randomized, controlled trial involving 116 surgeons in thirty-four centers in the United Kingdom was performed; 2352 participants were randomly allocated to be treated with or without a metal backing of the tibial component (409), with or without patellar resurfacing (1715), and/or with or without a mobile bearing (539). Randomization to more than one comparison was allowed. The primary outcome measures were the Oxford Knee Score (OKS), Short Form-12, EuroQol-5D, and the need for additional surgery. The results up to two years postoperatively are reported. RESULTS Functional status and quality-of-life scores were low at baseline but improved markedly across all trial groups following knee replacement (mean overall OKS, 17.98 points at baseline and 34.82 points at two years). Most of the change was observed at three months after the surgery. Six percent of the patients had additional knee surgery within two years. There was no evidence of differences in clinical, functional, or quality-of-life measures between the randomized groups at two years. CONCLUSIONS Patients have substantial improvement following total knee replacement. This is the first adequately powered randomized controlled trial, of which we are aware, in which the effects of metal backing, patellar resurfacing, and a mobile bearing were investigated. We found no evidence of an effect of these variants on the rate of early complications or on functional recovery up to two years after total knee replacement.

Experience matters: comparing novice and expert ratings of non-technical skills using the NOTSS system

There is growing evidence that non‐technical skills (NTS) are related to surgical outcomes and patient safety. The aim of this study was to further evaluate a behaviour rating system (NOTSS: Non‐Technical Skills for Surgeons) which can be used for workplace assessment of the cognitive and social skills which are essential components of NTS. A novice group composed of consultant surgeons (n = 44) from five Scottish hospitals attended one of six experimental sessions and were trained to use the NOTSS system. They then used NOTSS to rate surgeons’ behaviors in six simulated scenarios filmed in the operating room. The behaviours demonstrated in each scenario were compared to expert ratings to determine accuracy. The mode rating from the novice group (who received a short training session in behaviour assessment) was the same as the expert group in 50% of ratings. Where there was disagreement, novice raters tended to provide lower ratings than the experts. Novice raters require significant training in this emerging area of competence in order to accurately rate non‐technical skills.

Self-efficacy and goal importance in the prediction of physical disability in people following hospitalization: A prospective study

OBJECTIVES This prospective study evaluates the role of self-efficacy and goal importance in predicting decreases in disability in activities of everyday living. METHOD Disability, self-efficacy and goal importance were each assessed before and at 3 and 9 months after participants underwent joint replacement surgery. RESULTS Disability had decreased at 3 and 9 months post-surgery assessments. Self-efficacy beliefs were higher at 3 and 9 months following surgery while goal importance was increased at 9 months but not at 3 months. Medical variables and prior disability predicted disability at 3 months. Social-cognitive variables did not contribute to the prediction of 3 months disability. Pre-surgery goal importance and self-efficacy at 3 months were independent predictors of disability at 9 months after controlling for pre-surgery and 3 months disability. Evidence also suggested that goal importance and self-efficacy interacted to predict levels of disability at 9 months following surgery. CONCLUSIONS The findings demonstrate that recovery is governed not solely by medical phenomena but also by psychological variables and suggest that modification of these variables may have an impact on recovery outcomes. Moreover, attention should be paid to the timing of such intervention and to the length of follow-up.

THE MANAGEMENT OF WAR WOUNDS INVOLVING BONE

Over 200 high-velocity missile injuries treated in a low-technology environment were audited under the aegis of the International Committee of the Red Cross Hospitals in Afghanistan and Northern Kenya. Femoral fractures were treated either by traction or external fixation using a uniaxial frame. The results showed that patients treated by external fixation remained in hospital longer than those treated on traction. The positional outcome was identical in both groups. In tibial fractures the external fixator was only of extra benefit in those of the lower third when compared with simple plaster slabs unless more complex procedures such as flaps or vascular repair were to be performed. In complex humeral fractures, external fixation resulted in long stays in hospital and a large number of interventions when compared with simple treatment in a sling. We conclude therefore that in an environment where facilities are limited and surgeons have only general experience very careful initial wound excision is the most important factor determining outcome. The application of complex holding techniques was generally inappropriate.

Computerised measurement of tibiofemoral alignment

Tibiofemoral alignment has a direct correlation with the survival of total knee arthroplasty. Traditionally, it has been measured using a goniometer on radiographs. We describe new software which measures this alignment on scanned radiographs by automatically detecting bones in the image. Two surgeons used conventional methods and two clerical officers used the computerised routine to assess 58 radiographs of the knee on two occasions. There were no significant differences between any of the paired comparisons. The largest mean difference detected was 1.19 degrees. Across all comparisons, the mean correlation was 0.755. A standardised routine for measuring tibiofemoral alignment was the greatest factor in reducing error in our study. These results show that non-medical staff can reliably use the software to measure tibiofemoral alignment. It has the potential to measure all the parameters recommended by the Knee Society.

Prediction of bone strength from cancellous structure of the distal radius: can we improve on DXA?

Abstract: Recent studies show that structural parameters of bone, obtained from computerized image analysis of radiographs, can improve the noninvasive determination of bone strength when used in conjunction with bone density measurements. The present study was designed to assess the ability of image features alone to predict the mechanical characteristics of bones. A multifactorial model was used to incorporate simultaneously a number of characteristics of the image, including periodicity and spatial orientation of the trabeculae. Fifteen pairs (29 specimens) of unembalmed human distal radii were used. The cancellous bone structure was determined using computerized spectral analysis of their radiographic images and the bones were tested to failure under compression. Multilayered perceptron neural networks were used to integrate the various image parameters reflecting the periodicity and the spatial distribution of the trabeculae and to predict the mechanical strength of the specimens. The correlation between each of the isolated image parameters and bone strength was generally significant, but weak. The values of mechanical parameters predicted by the neural networks, however, had a very high correlation with those observed, namely 0.91 for the load at fracture and 0.93 for the ultimate stress. Both these correlations were superior to those obtained with dual-energy X-ray absorptiometry and with the cross-sectional area from CT scans: 0.87 and 0.49 respectively. Our observation suggests that image parameters can provide a powerful noninvasive predictor of bone strength. The simultaneous use of various parameters substantially improved the performance of the system. The multifactorial architecture applied is nonlinear and possibly more effective than traditional multicorrelation methods. Further, this system has the potential to incorporate other non-image parameters, such as age and bone density itself, with a view to improving the assessment of the risk of fracture for individual patients.

Assessment of performance in orthopaedic training

The reliable measurement of performance is a problem faced by training authorities worldwide. At a recent international orthopaedic conference, none of a group of experienced orthopaedic educators could report significant progress on this issue. The current Record of In Training Assessment (RITA)

Workplace‐based assessment: assessing technical skill throughout the continuum of surgical training

The Royal Colleges of Surgeons and Surgical Specialty Associations in the UK have introduced competence‐based syllabi and curricula for surgical training. The syllabi of the Intercollegiate Surgical Curriculum Programme (ISCP) and Orthopaedic Curriculum and Assessment Programme (OCAP) define the core competencies, that is, the observable and measureable behaviours required of a surgical trainee. The curricula define when, where and how these will be assessed.