Today's Veterinary Practice provides comprehensive information to keep every small animal practitioner up to date on companion animal medicine and surgery as well as practice building and management.
Issue link: http://todaysveterinarypractice.epubxp.com/i/591321
Today's VeTerinary PracTice | november/december 2015 | tvpjournal.com a PracTiTioner's Guide To FracTure ManaGeMenT Peer reviewed 30 Fractures occur commonly in both dogs and cats and, therefore, are frequently seen in general practice. This series of articles has been presented in 3 parts, with: • Part 1 describing fracture biomechanics, classification, and diagnosis • Part 2 discussing selection of fixation technique, external coaptation, identification of bone healing, and potential complications. This last article in the series addresses the options for internal fxation, including (Table 1): • Intramedullary (IM) pins and cerclage wire • Interlocking nails (ILNs) • External skeletal fixators (ESFs) • Bone plates and screws. SELECTION OF TECHNIQUE Internal Fixation Versus External Coaptation The advantages of addressing long bone fractures with internal fxation versus external coaptation include early return to function and maintenance of joint motion. Internal fxation is indicated for fractures that: • Are subjected to compression, shearing, and/or tensile forces • Are comminuted and/or long oblique • Cannot be reduced appropriately (see The 50/50 Rule). Selection of Internal Fixation Technique Choice of internal fxation method is based on fracture classifcation, affected bone, concurrent injuries, open versus closed and, of course, the forces being counteracted by the fxation method (Table 2). In addition, consider the ability, or inability, to reconstruct the cylinder of the bone, which affects the choice of fxation type and, ultimately, determines whether the bone can share in load bearing during healing or whether load bearing is done entirely by the implant until healing has occurred. A PrActitioner's Guide to FrActure MAnAGeMent Part 3: Selection of Internal Fixation Technique Meredith Kapler, DVM North Carolina State University David Dycus, DVM, MS, Diplomate ACVS (Small Animal) Veterinary Orthopedic & Sports Medicine Group, Annapolis Junction, Maryland Table 1. Fracture Fixation Methods INVASIVENESS & STABILITY PRIMARY FIXATION ANCILLARY FIXATION Least invasive Most unstable External Fixation External coaptation (cast or splint) Internal Fixation Intramedullary (IM) pin and/or K-wires Lag screws Most invasive Most stable External skeletal fxator (ESF) Full cerclage Interlocking nail (ILN) Hemi cerclage Bone plates and screws Note: Even though ESF and ILN are listed above bone plates and screws, the last 3 primary fxation methods offer complete stability depending on the fracture confguration; however, in general, ESF and ILN are less invasive than bone plates and screws. The 50/50 Rule the 50/50 rule states that fracture ends should have at least 50% contact to expect fracture healing , and that 50% reduction (contact) is the absolute minimum for bone healing to be possible, not probable . if the fracture cannot be reduced at least 50%, some type of internal fxation should be pursued.