Changes in strain patterns after implantation of a short stem with metaphyseal anchorage compared to a standard stem: an experimental study in synthetic bone

Short stem hip arthroplasties with predominantly metaphyseal fixation, such as the METHA® stem (Aesculap, Tuttlingen, Germany), are recommended because they are presumed to allow a more physiologic load transfer and thus a reduction of stress-shielding. However, the hypothesized metaphyseal anchorage associated with the aforementioned benefits still needs to be verified. Therefore, the METHA short stem and the Bicontact® standard stem (Aesculap, Tuttlingen, Germany) were tested biomechanically in synthetic femora while strain gauges monitored their corresponding strain patterns. For the METHA stem, the strains in all tested locations including the region of the calcar (87% of the non-implanted femur) were similar to conditions of synthetic bone without implanted stem. The Bicontact stem showed approximately the level of strain of the non-implanted femur on the lateral and medial aspect in the proximal diaphysis of the femur. On the anterior and posterior aspect of the proximal metaphysis the strains reached averages of 78% and 87% of the non-implanted femur, respectively. This study revealed primary metaphyseal anchorage of the METHA short stem, as opposed to a metaphyseal-diaphyseal anchorage of the Bicontact stem

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Hip arthroplasty in obese patients: rising prevalence – standard procedures?

We examined our experience and, in particular, complications associated with total hip arthroplasty in obese and morbidly obese patients. We prospectively gathered 50 patients in a matched control series including 25 obese and morbidly obese patients. All patients were operated using the direct lateral approach and standard postoperative protocols. Operating room time, complications, dislocations, blood loss, cup position and clinical parameters using the Harris Hip Score and the Western Ontario and McMaster Universities Arthritis Index results were compared. Although there were some significant differences in clinical outcomes, standard procedures yielded good overall results and an acceptable rate of complications. Details approaching this patient entity are being discussed

Qualitätssicherung: "TEP-App" für die Endoprothetik

Sens B, von Lewinski G, Albrecht U-V. Qualitätssicherung: "TEP-App" für die Endoprothetik. Deutsches Ärzteblatt. 2015;112(18):A-830/B-702/C-678

A short stem with metaphyseal anchorage reveals a more physiological strain pattern compared to a standard stem : an experimental study in cadavaric bone

The proposed advantages of short stem hip arthroplasties are bone preserving strategies and less soft tissue damage. Bone preserving strategies do not only include a more proximal resection of the femoral neck, but especially for short stem hip arthroplasties with predominantly metaphyseal fixation a presumed more physiologic load transfer and thus a reduction of stress-shielding. However, the hypothesized metaphyseal anchorage associated with the aforementioned benefits still needs to be verified. Unfortunately, mid- to long-term clinical studies are missing. Methods: Therefore, the METHA short stem as a short stem with proposed metaphyseal anchorage and the Bicontact® standard stem were tested biomechanically in three pairs of cadaveric femora while strain gauges monitored their corresponding strain patterns. Results: For the METHA stem, the strains in all tested locations including the region of the calcar were similar to conditions of cadaver without implanted stem. The Bicontact stem showed approximately half of strain of the non-implanted cadaveric femura with slightly increasing strain from proximal to distal. Conclusions: Summarizing, the current study revealed primary metaphyseal anchorage of the METHA short stem and a metaphyseal-diaphyseal anchorage of the Bicontact stem

The Influence of Tribological Pairings and Other Factors on Migration Patterns of Short Stems in Total Hip Arthroplasty

Over the last decade, the number of short stem total hip arthroplasty procedures has increased. Along with the possible benefits associated with short stems is a smaller implant-bone contact surface, which may have a negative influence on primary stability and impair osseointegration. Previous studies observed migration of short stems, especially within the first three months. The variables that influence migration in short stem hip implants remain unknown. Therefore, the purpose of this study was to associate the migration of short stems with its possible influencing variables. Migration data from two different short stem studies were retrospectively analyzed. Migration within the first two postoperative years was determined by model-based Roentgen stereophotogrammetric analysis. Migration was correlated to bearing couple, type and size of stem, size of acetabular cup, and age, gender, weight, and height of patients using a multiple factor analysis. Eigenvalue analysis explained 80.7% of the overall variance for the first three dimensions. The four most dominant variables in the first dimension were weight, stem size, acetabular cup size, and patient height (correlations of 0.81, 0.80, 0.71, and 0.70, resp.). None of the analyzed parameters (bearing couple, type and size of stem, size of acetabular cup, and age, gender, weight, and height of patients) affected the migration pattern of short stem THA with primary metaphyseal fixation

The Rate of Correctly Planned Size of Digital Templating in Two Planes—A Comparative Study of a Short-Stem Total Hip Implant with Primary Metaphyseal Fixation and a Conventional Stem

(1) Background: Preoperative templating is mainly conducted on an anteroposterior pelvic overview X-ray. For short stem hip arthroplasty, the choice of the optimal size is especially crucial to avoid complications. Thus, the study aimed to determine if there is an increased rate of correctly planned sizes using two radiological planes. (2) Methods: 50 patients with a conventional stem and 100 with a short stem total hip arthroplasty were analyzed. Without knowing the implanted size, three independent orthopedic surgeons performed digital templating: once using the anteroposterior pelvic overview only and once using the lateral view in addition. (3) Results: The rate of correctly planned sizes (+/−1 size compared to the inserted size) of templating with one plane was 86.3% ± 9.5% in short stem hip arthroplasty and 88.4% ± 6.0% in conventional stem arthroplasty. By adding the lateral view, the rate of correctly planned sizes was 89.9% ± 12.0% for the short stem hip arthroplasty group and 89.4% ± 9.8% for the conventional group (p > 0.1). (4) A potential positive effect of preoperative templating using an additional lateral X-ray view for short stem implants may be suggested based on the results of this study, which did, however, not reach statistical significance