Chapter 7 - Veterinary Instrumentation

7 TRAUMA IMPLANTS & INSTRUMENTSSherman Plates and ScrewsHistorical PerspectiveInstrumentsSherman Self-Tapping EquipmentKitsSherman Plating KitsSavings may be made by purchasing pre-assembled kits. The price istypically discounted by 5% less than the component price.Each Kit contains all you need including screws and implants. Full detailsof what the Kit includes is available at www.vetinst.com/kitsSHERMAN PLATING KITSSTAPKIT.2.0 2.0 Sherman Plating Kit £625.00STAPKIT2.7/3.5 2.7/3.5 Sherman Plating Kit £875.00Sherman Equipment and Screw BoxesSherman Equipment & Screw Box2.0 Equipment/ Screw BoxSherman Screws and Plates, long regarded as the poor relation of the AOtype, are worthy of re-examination, not least for their role in thedevelopment of internal fixation as we know it today.William O’Neill Sherman (1880-1970) was an eminent orthopaedic surgeonbased in Pittsburg. One of his roles was surgeon to the Carnegie SteelCompany which no doubt gave him access to engineering andmetallurgical resources necessary for his work on implants.His patent for a ‘surgical appliance’ US Patent 1,105,105 is dated July1914, before the invention of stainless steel. He specified the use ofVanadium, a steel alloy containing between 0.25 and 1 % vanadium,recognising the increase in strength and the increase in corrosionresistance conferred by the Vanadium. The added strength allowed him tode-bulk his implants.The screw specified had essentially a machine thread with self tappingflutes. It is interesting to note that pre-tapped screws had been tried butwere dropped as the tapping took too long. Exactly the same hashappened with current AO screws after decades of decrying the concept ofself tapping! The head was slotted but Sherman recognised the issue ofscrewdriver slippage and specified a dimple in the slot and a matchingprojecting portion on the screwdriver. Difficult to manufacture, this featuredoes not survive in current versions of Sherman Screws.The Plate design is concavo-convex in nature for extra strength. Thecurvature was such that only the margins of the plate bore onto the bone.Limited contact by any other name. The sinuous outline of the plate“avoids a construction having sharp corners or points of intersection, whichwould form the beginning of a break in the plate”. Minimal stress risers!Perhaps osteosynthesis has moved on with the development of metals,compression and locking technologies but Sherman’s role should not beforgotten. Oh... he was also an advocate of early mobilisation, very muchagainst the practice of the time. Maybe we have not come so far?The ShermanEquipment Boxincludes space for theessential equipmentand a screw rack.2.7/3.5 Equipment/Screw BoxSHERMAN EQUIPMENT/SCREW BOXBX20ST Box for 2.0 Sherman Screws and Equipment £185.00BX27ST Box for 2.7 Sherman Screws and Equipment £185.00BX35ST Box for 3.5 Sherman Screws and Equipment £185.00BX2735ST Box for 2.7/3.5 Sherman Screws and Equipment £185.00Screw Box 145mm x 105mm x 55mm deep forSherman ScrewsThis Screw Box has ahinged lid with a stainlessperforated insert. Themaximum screw length is55mm but the marking ofthe holes is indicated. ThisBox is for Sherman TypeScrews.SCREW BOXSH2000ST Box for 2.0 Sherman Screws £135.00SH2700ST Box for 2.7 Sherman Screws Marked 10-44 £135.00SH3500ST Box for 3.5 Sherman Screws Marked 10-57 £135.00SH2735ST Box for 2.7 & 3.5 Sherman Screws £135.00SH202735ST Box for 2.0, 2.7 & 3.5 Sherman Screws £135.00208