Early to midterm radiographic loosening of the press fit radial head prosthesis

Purpose: Many studies comparing the morphology of native radial head with the prosthesis have been published. However, there is limited information regarding the postoperative alignment of the articular surface following the radial head replacement. The purpose of this study is to evaluate the alteration of the end-plane angle in the modular radial head prosthesis with a press-fit cementless cylindrical stem. Methods: The study used 36 cadaveric radii. The press-fit size prosthesis with cylindrical stem was inserted into each specimen. The end-plane angles of the radial head before and after prosthetic replacement, were measured in coronal and sagittal planes with a digital inclinometer. The data were analyzed by paired t-test. Results: From paired t-test, there were statistically symmetrical end-plane angles before and after radial head replacement in both coronal and sagittal planes (p-value < 0.01). The mean of radial head end-plane angle alteration in the coronal plane was 3.62° (SD, 2.76°) (range, 0.3°–8.9°). In the sagittal plane, the mean of alteration was 5.85° (SD, 3.56°) degrees (range, 0.3° – 14.2°). Conclusion: The modular radial head prosthesis with cylindrical stem is in vitro able to restore the native end-plane angles of radial heads statistically when used in a press-fit fashion.

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Morphometry of the radiocapitellar joint: is humeral condyle diameter a reliable predictor of the size of the radial head prosthesis?

Journal of Shoulder and Elbow Surgery ◽

10.1016/j.jse.2018.01.017 ◽

2018 ◽

Vol 27 (6) ◽

pp. 1092-1096 ◽

Cited By ~ 3

Author(s):

Alfonso Vaquero-Picado ◽

Joaquín Núñez de Armas ◽

Samuel Antuña ◽

Raúl Barco

Keyword(s):

Radial Head ◽

Radial Head Prosthesis ◽

Reliable Predictor ◽

Humeral Condyle

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Auszugverhalten von Schaftfräsern*/Pull-out behavior of end mills – Experimental study on different clamping devices with various clamping mechanisms

wt Werkstattstechnik online ◽

10.37544/1436-4980-2018-05-79 ◽

2018 ◽

Vol 108 (05) ◽

pp. 353-358

Author(s):

E. Abele ◽

F. Ali ◽

M. Berger

Keyword(s):

Experimental Study ◽

Test Bench ◽

Mechanical Load ◽

Mechanisms Of Action ◽

Heavy Duty ◽

Press Fit ◽

Pull Out ◽

The Press ◽

End Mills ◽

Tool Position

Aus Schwerzerspanung und Turbinenschaufelfertigung ist bekannt, dass Werkzeuge aus dem Spannfutter ausgezogen werden. Die veränderte Werkzeugposition führt zur Abweichung von den vorgegebenen Toleranzen und einer geringeren Fertigungsqualität oder Beschädigung des Werkstücks. Der Artikel untersucht das Auszugsverhalten verschiedener Spannfutter. Mit einem Prüfstand können die Einflüsse der mechanischen Belastung und der Klemmlänge auf die Haltekraft im Pressverband betrachtet und die Wirkmechanismen beim Auszug des Werkzeuges aus dem Spannfutter sensorisch ermittelt werden.   From heavy-duty cutting and turbine blade manufacturing it is known that tools pull out from chucks. A change in tool position leads to deviations from tolerance and decreases manufacturing quality or damages the workpiece. This article explores the extension behavior of different chucks on a specifically designed test bench. This allows determining how mechanical load and clamping length influence the holding force in the press fit and what mechanisms of action affect the extraction of the tool from the chuck.

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Use of Osteofasciocutaneous Fibular Free Flap and Radial Head Arthroplasty in Trauma for Limb Salvage and Continued Elbow Function

Case Reports in Orthopedics ◽

10.1155/2018/8295736 ◽

2018 ◽

Vol 2018 ◽

pp. 1-4

Author(s):

Catherine Kilmartin ◽

Katharine D. Harper ◽

Chirag Mehta ◽

Joseph Thoder ◽

Andrew Newman

Keyword(s):

Limb Salvage ◽

Free Flap ◽

Radial Head ◽

Radial Head Prosthesis ◽

Review Of The Literature ◽

Joint Function ◽

Radial Head Arthroplasty ◽

Elbow Function ◽

Fibular Free Flap ◽

Proximal Forearm

Reconstructive flaps have revolutionized the ability of surgeons to restore function and cosmesis for patients. While reconstructive flaps have been used to bridge large defects due to oncologic or congenital maladies necessitating large debridements, few cases have observed salvage flaps in traumas which provide additional challenges secondary to an injury trajectory. This case report details use of an osteofasciocutaneous fibular free flap and radial head prosthesis to restore forearm function in a 64-year-old female with a comminuted fracture of the proximal radius. The patient has sustained a 5.5 cm epiphyseal radial defect with an associated 20 × 15 cm overlying tissue defect after serial debridement. In review of the literature, only one nontraumatic case using a combined free flap and radial head prosthesis for proximal forearm defect to restore joint function has been reported. We suggest that, for proximal forearm fractures, this technique can be used to restore elbow joint function in limb salvage.

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