TY  - JOUR
A1  - Hackl, Michael
A1  - Wegmann, Kilian
A1  - Kahmann, Stephanie Lucina
A1  - Heinze, Nicolai
A1  - Staat, Manfred
A1  - Neiss, Wolfram F.
A1  - Scaal, Martin
A1  - Müller, Lars P.
T1  - Radial shortening osteotomy reduces radiocapitellar contact pressures while preserving valgus stability of the elbow
JF  - Knee Surgery, Sports Traumatology, Arthroscopy
Y1  - 2017
U6  - https://doi.org/10.1007/s00167-017-4468-z
SN  - 1433-7347
VL  - 25
IS  - 7
SP  - 2280
EP  - 2288
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Lenz, Maximilian
A1  - Kahmann, Stephanie Lucina
A1  - Behbahani, Mehdi
A1  - Pennig, Lenhard
A1  - Hackl, Michael
A1  - Leschinger, Tim
A1  - Müller, Lars Peter
A1  - Wegmann, Kilian
T1  - Influence of rotator cuff preload on fracture configuration in proximal humerus fractures: a proof of concept for fracture simulation
JF  - Archives of Orthopaedic and Trauma Surgery
N2  - Introduction
In regard of surgical training, the reproducible simulation of life-like proximal humerus fractures in human cadaveric specimens is desirable. The aim of the present study was to develop a technique that allows simulation of realistic proximal humerus fractures and to analyse the influence of rotator cuff preload on the generated lesions in regards of fracture configuration.

Materials and methods
Ten cadaveric specimens (6 left, 4 right) were fractured using a custom-made drop-test bench, in two groups. Five specimens were fractured without rotator cuff preload, while the other five were fractured with the tendons of the rotator cuff preloaded with 2 kg each. The humeral shaft and the shortened scapula were potted. The humerus was positioned at 90° of abduction and 10° of internal rotation to simulate a fall on the elevated arm. In two specimens of each group, the emergence of the fractures was documented with high-speed video imaging. Pre-fracture radiographs were taken to evaluate the deltoid-tuberosity index as a measure of bone density. Post-fracture X-rays and CT scans were performed to define the exact fracture configurations. Neer’s classification was used to analyse the fractures.

Results
In all ten cadaveric specimens life-like proximal humerus fractures were achieved. Two III-part and three IV-part fractures resulted in each group. The preloading of the rotator cuff muscles had no further influence on the fracture configuration. High-speed videos of the fracture simulation revealed identical fracture mechanisms for both groups. We observed a two-step fracture mechanism, with initial impaction of the head segment against the glenoid followed by fracturing of the head and the tuberosities and then with further impaction of the shaft against the acromion, which lead to separation of the tuberosities.

Conclusion
A high energetic axial impulse can reliably induce realistic proximal humerus fractures in cadaveric specimens. The preload of the rotator cuff muscles had no influence on initial fracture configuration. Therefore, fracture simulation in the proximal humerus is less elaborate. Using the presented technique, pre-fractured specimens are available for real-life surgical education.
KW  - Proximal humerus fracture
KW  - Biomechanical simulation
KW  - Fracture configuration
KW  - Fracture simulation
KW  - Rotator cuff
Y1  - 2022
U6  - https://doi.org/10.1007/s00402-022-04471-9
SN  - 1434-3916
PB  - Springer
CY  - Berlin, Heidelberg
ER  - 
TY  - CHAP
A1  - Dachwald, Bernd
A1  - Ulamec, Stephan
A1  - Kowalski, Julia
A1  - Boxberg, Marc S.
A1  - Baader, Fabian
A1  - Biele, Jens
A1  - Kömle, Norbert
ED  - Badescu, Viorel
ED  - Zacny, Kris
ED  - Bar-Cohen, Yoseph
T1  - Ice melting probes
T2  - Handbook of Space Resources
N2  - The exploration of icy environments in the solar system, such as the poles of Mars and the icy moons (a.k.a. ocean worlds), is a key aspect for understanding their astrobiological potential as well as for extraterrestrial resource inspection. On these worlds, ice melting probes are considered to be well suited for the robotic clean execution of such missions. In this chapter, we describe ice melting probes and their applications, the physics of ice melting and how the melting behavior can be modeled and simulated numerically, the challenges for ice melting, and the required key technologies to deal with those challenges. We also give an overview of existing ice melting probes and report some results and lessons learned from laboratory and field tests.
KW  - Ice melting probe
KW  - Ice penetration
KW  - Icy moons
KW  - Ocean worlds
KW  - Mars
Y1  - 2023
SN  - 978-3-030-97912-6 (Print)
SN  - 978-3-030-97913-3 (Online)
U6  - https://doi.org/10.1007/978-3-030-97913-3_29
SP  - 955
EP  - 996
PB  - Springer
CY  - Cham
ER  -