Musa, Agaba

English

AJOL - African Journals Online

South Sudan Medical Journal                                                                                  Vol 6. No 2. May 2013   SSMJ Vol 6. No 2. May 2013 Downloaded from www.southsudanmedicaljournal.com31MaiN artiClESHow I improvised an external fixator to  manage open fracturesAgaba Musaa  IntroductionOrthopaedic surgery is a technical specialty. In Nigeria, as in most developing countries, insufficient funding is available for technological advancement [1]. Indigenous hospital technology can reduce cost of  managing injuries needing surgery, many of  which are caused by an epidemic of  road traffic accidents [2].  This paper explains how to make and use an improvised external fixator for the management of  open fractures and instruments used for its clinical application. This is an improved version of  an earlier external fixator [3]. the improvised external fixator and accompanying instruments A. The external fixatorThe improvised external fixator (Figure 1) consists of  two metal (iron or aluminum) plates (breadth 1.7 - 2cm; thickness 1.7 - 2mm). The plates are drilled so that the distance between two holes is 2cm and mirror symmetry of  each other. Screws are passed through the holes. The length of  the plate is customised. Tightening the nuts on the screws reduces the distance between the metal bars. In this way implants between them are clamped. The grip between the metal plates is strong enough to retain a 15-kg weight and so strong that a cement bag, 50-kg weight cannot slip out of  its grip. Kirschner wires, Schanz screws, Denham and Steinmann pins are implants that can be used with this external fixator. Denham and Steinmann pins are used as full pins. Schanz screws are used as half  pins. Kirschner wires can be used as both full and half  pins. How to make the external fixatorStep 1(Figure 2a): The materials, plates (made of  iron or aluminum), screws (made of  iron; diameter=4mm) and nuts (made of  iron) are usually sourced from the local junk yard. The plates are often donated. The screws are the type used to attach vehicle number plates in Nigeria. If  the plate is too wide, it is cut to the required size (breadth between 1.7cm and 2cm; thickness between 1.7mm and 2mm) with an artisan’s grinding machine. Step 2 (Figure 2b): The desired plate is wrapped with a masking tape. A midline is drawn on it. Holes are drilled along the midline at 2cm intervals. This plate can be used as a template for drilling others. The drilling machine used is usually a small bench drilling machine (power=350 watts; revolution not more than 2700 revolutions per minute; maximum diameter of  drilling bit the machine can accommodate=13mm). The bit (diameter=4mm) used in drilling the plates is run at least twice. This widens the holes for the nuts (diameter=4mm).  B. The modified powered drill [4]Powered drills designed for orthopedic surgery are expensive and the spare parts are not easily available in Nigeria. For this reason a commonly available powered technician’s drill is modified by reducing the quantity of  electricity it uses. This is achieved by diverting electricity through a domestic ceiling fan switch (a rheostat) Figure 1. The improvised external fixatorFigure 2a. Plates, screws and nuts used for making the improvised external fixator.Figure 2b. Arrow points to an area marked for drilling of  hole on a plate.a Department of  Surgery, Usamanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria.  Agabaidu@Ymail.comSouth Sudan Medical Journal                                                                                  Vol 6. No 2. May 2013   SSMJ Vol 6. No 2. May 2013 Downloaded from www.southsudanmedicaljournal.comMaiN artiClES32before reaching it. Thus the number of  revolutions per minute(r/m) is reduced from 2500r/m to 800r/m.  This also reduces the heat generated by friction. The more the heat generated during drilling of  holes in bones the more the necrosis along the pin tracts and the higher the possibility of  pin tract infection which will cause the pins to wobble and loosen. The chuck of  the powered technician’s drill does no communicate with the interior of  the drill. For this reason only short drilling bits can be used. Long drill bits are not suitable becausethey can break as result of  the torque.C. Tools for assembling the external fixatorThese are shown in Figure 3.Notes for Figure 3. From left to right:• Screw driver (one end is star-shaped and the other end is flat). This is used for tightening a screw when the head is under direct vision.• Screw driver (one end is star-shaped and at right angle to the other end which is flat). This is used for tightening a screw when the head is not under direct vision.• Flat spanner. This used for tightening a nut. It is specific for the particular nut and the distance between two holes is also specific for the flat spanner.• A pair of  long nose pliers. These are used for holding a nut that is under direct vision.d. a distraction/compression deviceThis improvisation consists of  a long threaded metal rod that passes through two pieces of  metal pipe. A small piece of  metal plate is welded at an angle to each pipe. The angle between the pipe and the metal plate face each other when compression between fracture fragments is required. The angles face opposite directions when distraction is required. During compression of  fragments a washer is   placed at the each end of  the bolt. This washer is succeeded by a nut at each of  these two ends of  the bolt (Figure 4). Turning of  the nut pushes the wings of  the pipes against the pins. During distraction of  fragments two washers are placed in between the pipes but before these watchers two nuts had already been passed to the middle of  the rod. Turning the nuts widens the distance between them. Thus fracture fragments are distracted. ConclusionThis technology can be easily duplicated. The external fixator and compression/distraction devices are easily made in the hospital workshop from scraps. It takes on average an hour to make this external fixator. Although it looks primitive, its grip is a proof  of  its mechanical stability which prevents fracture re-displacement after reduction.Thus good outcome of  treatment of  open tibial shaft fractures can be assured. The only thing these devices lack is aesthetics which can be improved upon but this may increase costs – which defeats the purpose of  reducing the costs through the development of  indigenous technology. The implants used with this improvised external fixator are standard, factory-made types and purchased from international suppliers. ReferencesМusa A A. Indigenous hospital technology in Nigeria: 1. Problems and recommendations. West African Journal of  Medicine 2001; 20(3): 268-269.Natulya V M, Reich M R. The neglected epidemic: road 2. traffic injuries in developing countries. British Medical Journal 2002; 324: 1139-1141.Musa A A. A Simple external fixator. Nigerian 3. Journal of  Orthopaedics and Trauma 2004; 3(1): 61-67.Musa A A. How to adapt an ordinary drilling machine 4. for orthopaedic surgery. West African Journal of  Medicine 2002: 21: 59.Ali-Akpajiak S C A, Pyke T. Measuring poverty in 5. Nigeria. Oxford, 2003 Oxfam.Figure 3. Tools for assembling the fixator.  Figure 4. The improvised distraction/compression device mounted for compression

How I improvised an external fixator to manage open fractures

https://www.ajol.info/index.php/ssmj/article/download/132594/122192

How I improvised an external fixator to manage open fractures

Abstract

Similar works

Full text

Available Versions

AJOL - African Journals Online