Marc-Daniel Ahrend

Predictive ability of a comprehensive incremental test in mountain bike marathon

Objectives Traditional performance tests in mountain bike marathon (XCM) primarily quantify aerobic metabolism and may not describe the relevant capacities in XCM. We aimed to validate a comprehensive test protocol quantifying its intermittent demands. Methods Forty-nine athletes (38.8±9.1 years; 38 male; 11 female) performed a laboratory performance test, including an incremental test, to determine individual anaerobic threshold (IAT), peak power output (PPO) and three maximal efforts (10 s all-out sprint, 1 min maximal effort and 5 min maximal effort). Within 2 weeks, the athletes participated in one of three XCM races (n=15, n=9 and n=25). Correlations between test variables and race times were calculated separately. In addition, multiple regression models of the predictive value of laboratory outcomes were calculated for race 3 and across all races (z-transformed data). Results All variables were correlated with race times 1, 2 and 3: 10 s all-out sprint (r=−0.72; r=−0.59; r=−0.61), 1 min maximal effort (r=−0.85; r=−0.84; r=−0.82), 5 min maximal effort (r=−0.57; r=−0.85; r=−0.76), PPO (r=−0.77; r=−0.73; r=−0.76) and IAT (r=−0.71; r=−0.67; r=−0.68). The best-fitting multiple regression models for race 3 (r2=0.868) and across all races (r2=0.757) comprised 1 min maximal effort, IAT and body weight. Conclusion Aerobic and intermittent variables correlated least strongly with race times. Their use in a multiple regression model confirmed additional explanatory power to predict XCM performance. These findings underline the usefulness of the comprehensive incremental test to predict performance in that sport more precisely.

Treatment strategy for posttraumatic complex deformity. After bilateral femoral shaft fractures

A case of complex posttraumatic deformity after bilateral femoral shaft fractures is reported. Different possibilities for correction in cases of valgus malalignment combined with internal rotation deformity as well as shortening combined with external rotation deformity are presented. Oblique osteotomy and a motorized femoral extension nail were used.ZusammenfassungBerichtet wird über einen Fall mit komplexer posttraumatischer Deformität an beiden Beinen nach Femurschaftfraktur. Dargestellt werden Korrekturmöglichkeiten bei Kombinationsfehlstellung mit Genu valgum und Innentorsionsabweichung sowie mit Verkürzung und Außentorsionsabweichung. Dafür kommen zum einen die Schrägosteotomie und zum anderen ein motorisierter Verlängerungsnagel zur Anwendung.AbstractA case of complex posttraumatic deformity after bilateral femoral shaft fractures is reported. Different possibilities for correction in cases of valgus malalignment combined with internal rotation deformity as well as shortening combined with external rotation deformity are presented. Oblique osteotomy and a motorized femoral extension nail were used.

Behandlungsstrategie bei posttraumatischer Komplexdeformität@@@Treatment strategy for posttraumatic complex deformity: Nach Femurschaftfraktur beidseits@@@After bilateral femoral shaft fractures

A case of complex posttraumatic deformity after bilateral femoral shaft fractures is reported. Different possibilities for correction in cases of valgus malalignment combined with internal rotation deformity as well as shortening combined with external rotation deformity are presented. Oblique osteotomy and a motorized femoral extension nail were used.ZusammenfassungBerichtet wird über einen Fall mit komplexer posttraumatischer Deformität an beiden Beinen nach Femurschaftfraktur. Dargestellt werden Korrekturmöglichkeiten bei Kombinationsfehlstellung mit Genu valgum und Innentorsionsabweichung sowie mit Verkürzung und Außentorsionsabweichung. Dafür kommen zum einen die Schrägosteotomie und zum anderen ein motorisierter Verlängerungsnagel zur Anwendung.AbstractA case of complex posttraumatic deformity after bilateral femoral shaft fractures is reported. Different possibilities for correction in cases of valgus malalignment combined with internal rotation deformity as well as shortening combined with external rotation deformity are presented. Oblique osteotomy and a motorized femoral extension nail were used.

Behandlungsstrategie bei posttraumatischer Komplexdeformität

A case of complex posttraumatic deformity after bilateral femoral shaft fractures is reported. Different possibilities for correction in cases of valgus malalignment combined with internal rotation deformity as well as shortening combined with external rotation deformity are presented. Oblique osteotomy and a motorized femoral extension nail were used.ZusammenfassungBerichtet wird über einen Fall mit komplexer posttraumatischer Deformität an beiden Beinen nach Femurschaftfraktur. Dargestellt werden Korrekturmöglichkeiten bei Kombinationsfehlstellung mit Genu valgum und Innentorsionsabweichung sowie mit Verkürzung und Außentorsionsabweichung. Dafür kommen zum einen die Schrägosteotomie und zum anderen ein motorisierter Verlängerungsnagel zur Anwendung.AbstractA case of complex posttraumatic deformity after bilateral femoral shaft fractures is reported. Different possibilities for correction in cases of valgus malalignment combined with internal rotation deformity as well as shortening combined with external rotation deformity are presented. Oblique osteotomy and a motorized femoral extension nail were used.