Herbert screw

The Herbert screw is a special implant that is used in medicine for the osteosynthetic treatment of the scaphoid bone in the context of a scaphoid fracture or pseudarthrosis . It was developed by Timothy James Herbert together with W. E. Fisher in the late 1970s.

Scaphoid pseudarthrosis (left picture) and treatment with Herbert screw (right)

principle

The Herbert screw consists of a screw shaft and short threads at the beginning and at the end (double-threaded screw), both of which are slightly larger in diameter than the screw shaft; a screw head is missing to make it easier to place it completely in the bone. The screw is hollow (“cannulated”) and has a hexagon socket on the distal side so that it can be screwed in with a special tool using a guide wire (Kirschner wire). In order to create an axial tensile force on the fragments, the thread pitch on the proximal thread is smaller than on the distal one , so that the distal fragment is mechanically pulled towards the proximal when screwing in ( lag screw ) . This creates pressure on the fracture gap that promotes fracture healing (interfragmentary compression).

use

During the operation, the broken navicular bone is first repositioned and, if necessary, fixed, then the screw is inserted. In the case of pseudarthrosis, a bone transplant is usually required to enable stable healing. The Herbert screw can - but usually does not have to - be removed again later.

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !

Individual evidence

1. ↑ RB Brauer et al .: The use of the Herbert screw with the freehand method for osteosynthesis of the fresh scaphoid fracture . In: The trauma surgeon , Springer, Berlin / Heidelberg 2001; link.springer.com . ISSN  0177-5537 (Print) ISSN  1433-044X (Online)
2. ↑ A. Englert et al .: The scaphoid fracture of the athlete - diagnosis and therapy . In: Sport-Orthopädie Sport-Traumatologie , Urban & Fischer, 2006, Issue 1, pp. 9–12; elsevier.isoftmedia.de ( Memento of the original from May 22, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. 
3. ^ M. Küntscher et al .: Treatment of proximal navicular pseudarthroses and fractures with the mini Herbert screw via a dorsal approach . In: The trauma surgeon , Springer, Berlin / Heidelberg 2001; ISSN  0177-5537 (Print) ISSN  1433-044X (Online)
4. ↑ H. Reimer et al. a .: For the extended indication of Herbert screw osteosynthesis. In: European Journal of Trauma . Urban & Vogel, 1995; ISSN  1439-0590 (Print) ISSN  1615-3146 (Online)