Your First Fracture Repair: Principles and Planning in Practice
Hannah Gritti, British Veterinary Orthopaedic Association
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When repairing a fracture,the main aims are to achieve alignment, optimal healing environment and the avoidance of fracture disease which includes muscle atrophy/contracture, joint stiffness and disuse osteoporosis and therefore in suboptimal limb function. So how do you translate this in practice? The following considerations are appropriate for a diaphyseal shaft fracture of e.g. the femur.
Principles of Fracture Management
Consider mechanical stability and fracture biology.
Bone healing relies on:
1. Stability
Stabilising the fracture can reduce the risk of further damage, provide analgesia, and control soft tissue swelling.
Orthogonal radiographs of the fractured bone should be taken, and usually also the contralateral limb. Careful inspection of the images will help to detect fragments, fissures and other potential complicating factors. The ability to measure the bone and pre-contour bone plates is invaluable so use a scale marker and implant templates (digital or acetates). Have the radiographs available during surgery for immediate reference.
Choose between either open reduction and internal fixation (ORIF) or closed reduction for example with an ESF. Implant selection is based on awareness of forces around a fracture. Consider patient size, temperament and muscle mass when considering implant selection, and have a back-up plan if your first choice becomes unsuitable during surgery.
Implants:
− Non-locking (e.g., dynamic compression plate [DCP], limited contact DCP)
These plates must have good bone apposition along the length of the plate and require perfect contouring. They can be applied in bridging, neutralisation or compression mode depending on the type of fracture e.g. a dynamic compression plate is used to compress a transverse fracture.
− Locking plates (e.g., locking compression plate [LCP] or string-of-pearl [SOP])
The screw heads lock into the plate. The plate is not pressed down onto the bone therefore the plate and bone do not have to be in direct contact; only approximate contouring is required.
2.Reduction
Are you aiming for primary or secondary bone healing and is anatomical reconstruction appropriate? Reconstruction is more difficult with comminuted fractures with many free fragments that if devascularised, may significantly delay bone healing or result in non union. It is possible to leave fragments undisturbed with bridging plates where the plate bears the entire load (forces) across a fracture gap. There must be sufficient bone stock proximal and distal to the fracture to insert two or three bicortical screws as a minimum, and ideally more.
The ease of reduction is affected by time to surgery, muscle contracture and operative technique. If possible use the ‘hanging limb’ technique i.e. using the animal’s bodyweight to distract to the fracture whilst suspended during preparation pre-operatively. Also use an assistant and/or retractors. Positioning the limb parallel to the table helps with angulation of the drill and implants and is appropriate for a medial or lateral approach. Secure the patient on the table and use positioning aids.
3.Prevention of infection
Good preparation and planning will minimise the length of surgery.
Ensure aseptic technique for the fracture, bone graft and local block sites. If using the hanging limb technique, ensure that an assistant can hold the leg whilst you drape the area, and use sterile bandage or smaller drapes to isolate the foot, without contaminating your incision site.
Good haemostasis including the use of swabs, haemostats and electrocautery is one of Halsted’s principles of surgery and is one factor that will help to reduce the incidence of post-operative surgical site infection.
Use antibiotic prophylaxis if necessary but ensure that adequate concentrations of antibiotic are present in advance of the first incision i.e. give the first dose at the time of pre-med or anaesthetic induction.
4.Preservation of blood supply.
Know the anatomy and surgical approach to your fracture site; this will depend on soft tissue cover, any wounds and accessing the tension surface of the bone rather than the compression (bending) surface. Employ Halsted’s principles of surgery including sharp dissection between muscle and fascial planes. Minimum disturbance of the fracture haematoma, vessels and soft tissues is favourable for healing. Keep tissues moist with sterile saline irrigation.
5.Encouraging limb use
Plan your approach to avoid iatrogenic nerve damage, achieve good fracture alignment and provide adequate analgesia for a fast return to function post-op.
Planning the Repair
Check you have everything you need and that it will be sterilised in time for surgery.
Orthopaedic Kit
1.Plates and screws kit:
Fig. 1:
2.Retractors:
Fig. 2
3.Jacob’s Chuck with key and extensions for use with long pins and the drill.
Fig. 3
4. Drill:
Fig. 4
5. Drill guide:
Fig. 5
6. Depth gauge:
Fig. 6
7. Tap with tap handle:
Fig. 7
8. Pin cutter:
Fig. 8
9. Plate Benders:
Fig. 9
10. ESF kit:
Fig. 10
11.Wire and wire benders/cutters:
Fig. 11
12. Pins:
Fig. 12
13. Drill sleeve:
Fig. 13
Further Reading