LOCKED NAILING - TARGETTING - TORSION - sagital coronal femur tibia

1. https://www.sciencedirect.com/science/article/pii/S1877056811002805
1. torsional bending in solid nail is almost nil 
2. Due to the elasticity of the system and especially of the drill bit, the latter could even pass the interlocking hole of the nail up to a nail deformation of 15.5 mm
3. In an experimental study on 20 intact human cadaveric tibiae, Krettek et al. demonstrated 
1. an average implant deformation in the sagittal plane of −7.8 ± 5.8 mm (range, 19.2 mm) 
2. and in the coronal plane of −4.5 ± 3.5 mm (range, 14.3 mm) for combined 8-mm and 9-mm nail diameters, respectively [8]. 
3. n a similar study on 20 intact fresh human cadaveric femora, the average deformation of a 9-mm solid nail averaged −3.1 ± 4.3 mm (range, 15.2 mm) in the sagittal plane
4. and 18.2 ± 10.0 mm (range, 47.8 mm)  and coronal plane, [9]. 
5. Rotational deformation along the longitudinal axis of the nail was insignificant in both studies. 
4. Combining these data with the results of the present study indicates that, for distal tibial locking, the accuracy of a simple proximally mounted targeting device should be almost sufficient, whereas for femoral locking an adjustment (at least in one plane) seems to be essential
1. For instance in tibial nailing, an additional targeting device, that allows perfect alignment in the sagittal plane would be sufficient as the deformation in the coronal plane is negligible.
   
2. A.Hashemi-NejadN.GarlickN.J.Goddard
   https://doi.org/10.1016/0020-1383(94)90139-2Get rights and content
1. A simple jig to ease the insertion of distal screws in intramedullary locking nails
2. Abstract
   Distal locking of closed intramedullary nails can be time consuming and expose the surgeon to unnecessary increased ionization radiation. A simple jig is described which facilitates the insertion of the second distal locking screw, using the first drill hole as a pilot. This tool reduces the operating and the ionizing radiation exposure time.
3.  A modified freehand method using a cannulated drill bit for the insertion of distal locking screws for interlocking intramedullary nails is described. It should be useful to introduce surgeons to interlocking and to aid those who are not comfortable with the freehand method.
1. A simple jig to ease the insertion of distal screws in intramedullary locking nails
   A.Hashemi-NejadN.GarlickN.J.Goddard
   https://doi.org/10.1016/0020-1383(94)90139-2
4.  An improved method of screw placement combining image intensification and laser light.
   Goulet JA, Londy F, Saltzman CL, Matthews LS
1. Clinical Orthopaedics and Related Research, 01 Aug 1992, (281):199-203
   PMID: 1499210 
2. a laser guiding system in addition to the standard image intensifier was used
3. 97% of the distal femoral drill holes attempted were successfully made with the first pass of a drill. Little or no resistance to the drill was met from contacting the femoral nail. 
4. Average fluoroscopy time was 0.4 minute.
5.  Laser-assisted screw placement requires relatively inexpensive modifications of existing equipment and is easy to master. 
6. Compared with the more commonly used freehand method, laser-assisted screw placement appears to offer a reduction in the amount of time and radiation exposure required to insert distal interlocking femoral screws.
5.  The effectiveness of the external distal aiming device in intramedullary fixation of tibial shaft fractures 
1. George C. Babis, Ioannis S. Benetos, Aristides B. Zoubos & Panayotis N. Soucacos
   Archives of Orthopaedic and Trauma Surgery volume 127, pages905–908(2007)
   USES ORTHOFIX)= SUCCESS 51 OF 63 
6.  SURESHOT FROM SMITH NEPHEW
1. OFTEN WORKDS
7. A new distal targeting device for closed interlocking nailing
   Sarantis Tyropoulos*,Correspondence information about the author Sarantis TyropoulosEmail the author Sarantis Tyropoulos, Christos Garnavos
1. The proposed device has been designed to be mounted on the image-intensifier, is absolutely stable, eliminates the need for a specialised X-ray technician and allows the surgeon to be away from the radiation beam (direct or scattered). It also permits image intensification in the anteroposterior view, without losing the target. The device has proved its reliability in the operating room during closed interlocking nailing procedures.
8. Injury. 1998;29 Suppl 3:C29-39.
   Intraoperative control of axes, rotation and length in femoral and tibial fractures. Technical note.
1. Krettek C1, Miclau T, Grün O, Schandelmaier P, Tscherne H
2. These include: 
1. the 'cable techniques' for the determination of varus-valgus malalignment; 
2. the 'hypertension test', 
3. 'radiographic recurvatum sign', 
4. 'tibial plateau sign', and 'meterstick technique' for length analysis; and 
5. the 'hip rotation test', 
6. lesser trochanter shape sign', 
7. 'cortical step sign', and 
8. 'diameter difference sign' for rotational analysis. 
3. For each of the listed techniques, basic principles, technical instructions, limitations, advantages, and disadvantages are described.
9. USING MICROSCRIBE DIGITISER
1. http://www.jmbe.org.tw/files/141/public/141-1029-1-PB.pdf
1.  The transformed coordinates of the axis of the distal locking screw can be further calculated from the transformation matrix and the axis of the distal guiding rod measured prior to nail insertion  Figure 3 shows the details of the coordinate transformation relationships
2. sound  used = frequency of beeps increases asthe distance beweenthe tip of probe and target decreases
10. “Computer-assisted fluoroscopy-based reduction of femoral fractures and antetorsion correction,”  - brain lab etc
11. circular hole 
1. awl on bone till in center= and mark the bone 
12.  [Insertion of distal screws in interlocking nailing using a new free-hand control device] 
1. Pennig D, Brug E Der Unfallchirurg, 01 Jul 1989, 92(7):331-334Language:gerPMID: 2762819 
2. Abstract 
3. The device consists of two metal rings on both ends of an X-ray translucent cylinder with a central 4-mm hole in it. A pin with a sharp tip (diameter 4 mm, length 160 mm) is inserted through the hole. Using the image intensifier, the device is then placed so that the sharp tip of the pin points to the bone. The device is moved until the two metal rings are superimposed on each other and give the impression of one ring with the nail hole in the middle. On the screen the pin then appears as a dot inside the nail hole.
13.  Reducing radiation exposure in intra-medullary nailing procedures: Intra-medullary endo-transilluminating (iMET)
1. WilliamChuabJyhpyngWangcShuenn-TsongYoungaWoei ChynChua  
2. https://doi.org/10.1016/j.injury.2009.04.008Get rights and content 
3. Abstract
1. A visible light source was inserted into the medullary bone cavity in order to detect the distal interlocking screw holes. The light penetrates out of the bone surface, revealing the position of the screw hole, and this allows the subsequent drilling and placing of the interlocking screw to be free of fluoroscopy. Among the 19 consecutive tibia-fracture patients recruited for this study, no repetition of the drilling procedure or insertion of a transverse interlocking screw was needed. 
2. The average time to finish the insertion of one distal interlocking screw was 4.1 ± 1.8 min. It was extrapolated that 13–41% of previous radiation exposure levels could be saved. The non-fluoroscopic approach thus decreases the health hazards that the patients are experiencing as well as those of the surgical team who need to perform such intra-medullary nailing operations on a routine basis.
14. https://content.iospress.com/articles/international-journal-of-applied-electromagnetics-and-mechanics/jae01063 
1. A system for distal fixation of intramedullary nails
   Authors: Martinez, M. Rigobertoa | Minor, M. Arturoa; *Affiliations: [a] Departament of Electrical Engineering, Bioelectronics Section, Center of Research and Advanced Studies of the National Polytechnic Institute, Zacatenco, Mexico
2. Correspondence: [*] Address for correspondence: Dr. M. Arturo Minor, Department of Electrical Engineering, Bioelectronics Section, Center of Research and Advanced Studies of the National Polytechnic Institute. Av. IPN 2508, Del. Gustavo A. Madero, D.F. Mexico. Tel.: +52 5550613800; Fax: +52 50613981; E-mail: aminor@cinvestav.mx 
3. Abstract: This article describes the design and construction of an electronic device to assist orthopedic surgeons in the intramedullary nailing of long bones. The objective of the system is to reduce the cumulative radiation to which surgeons are exposed while performing the operation, as well as reduce the time required to complete the task. The system uses the magnetic flux of permanent magnets and electronic sensors to determine, without the need for a fluoroscope, the position of the distal hole in the rod. Tests show the system is feasible.
15. https://ieeexplore.ieee.org/abstract/document/6411140 
1. Assistant System for Locking Intramedullary Nails Used to Repair Fractures of the Long Bones  = Publisher: IEEE Martinez Rigoberto ; Minor Arturo  
2. Abstract: 
3. The proposed method uses permanent magnets and magnetic sensors to locate on the bone the exact drill point with which to secure the nail. The method is developed with the intention of reducing the large doses of radiation to which surgeons and patients are exposed when applying traditional nailing methods. The system is portable and runs on batteries, so it is totally autonomous, easy to use and very reliable.