Open fractures internal fixation

1. Open fractures - immediate care:

When Ihe case first presents, ensure that the following procedures are carried out in every case: (I) Take a bacteriology swab from the wound. (2) Commence a short course of appropriate antibiotics (see p. SO). (.1) Cover ihe wound with care, using sterile dressings (to reduce the risks of secondary (hospital) infection). (4) Apply temporary splintage (e.g. a plaster back shell or, if appropriate, an inflatable splint).

Wound Care Open Fracture

4. Type I cntd: Carry out a thorough (preferably pulsatile) wound lavage. Up to 10 Lof normal saline may be used (followed, by some, with 2 L of bacitracin-polymyxin solution) (I). Primary closure of the skin is not advisable, but it may be helpful to use subcutaneous anchoring sutures (2) to prevent undue retraction and aid secondary suture. Apply a dressing which ensures the tissues remain moist (e.g. saline-soaked swabs over vaseline gauze). Attention must then be paid lo fixation of the fracture.

2. Type I, technically open fractures:

(I) The risks of infection are slight and are unlikely lo be lessened by wide exposure (although Ihis is advocated by some). The wound should be thoroughly cleaned (2) and a sterile dressing applied locally (3). Thereafter the method of supporting the fracture must be decided (see p. 79 and also Regional Injuries). If a plaster cast is being applied there must be allowance for swelling, e.g. by using a baekshell or by splitting a cast applied over copious wool.

Tetanus Treatment Image

hours; if necessary, perform any secondary debridement. If the wound remains clean, the aim should be to carry out a (delayed primary) wound closure under repeat antibiotic cover at 5 days (I). If the wound cannot he closed without tension, any remaining defect should be covered with a splii-skin meshed graft (2) (which allows the escape of exudate). If Ihe wound is dirty, then it should be treated by radical excision of all necrotic and infected tissue every 2-3 days until clean and ready to be grafted.

3. Type I, open from within out: The wound is small with clean or minimally bruised, viable edges ( I ). The skin edges may be minimally excised, and the wound extended (2) to allow a thorough inspection of the soft tissues and bone ends. It is unlikely thai much will be required in the form of excision of contaminated or avascular tissue lo achieve a thorough debridement. Advantage may be taken of the exposure to allow an act urate open reduction of the fracture.

6. Type II open fractures: These should be managed along similar lines. In Type III injuries perform a rigorous lavage and debridement (with, if needed, wound enlargement): all foreign material must be removed along with any completely devitalised tissue (including small hone fragments). The wound should be left open but dressed so as to prevent drying out. To facilitate wound management (conducted as in Frame 5) an external fixator or locked intramedullary nail may be the best way to hold the fracture.

7. Type III cntd: If bone Is exposed, the aim should be lo get it covered within live days, to reduce the risks of secondary infection. Split skin grafts will only survive if applied to a vascular bed. therefore they cannot be used over open joints, bone devoid of periosteum, and tendons without paratcnon. Thought must be given to future access (e.g. for bone grafting should union fail). In these circumstances other methods of cover must be employed. These should only be undertaken by a surgeon experienced in plastic surgical techniques, and consultation with a plastic surgeon prior lo the initial procedure, with later transfer to a plastic surgical unit, is highly desirable.

t he local fasciocutancoiis Hap: This is the commonest and most useful technique. These Haps include skin and fascia, but not muscle. (Skin Haps in the lower limb which do not include the fascial layer have a poor record of success.) Distally based Haps are sometimes used to cover defects in the distal third of the leg. Careful planning of the Hap is required. In the example (left) of the defect (I) to be covcred. the anterior limb (2) of the Hap to be raised is placed 1-2 cm posterior to the posteromedial border of the tibia. The posterior limb (3) may cross the midline. Alter the llap has been raised and swung (4). the resulting defect is covered with split skin grafts.

8. Type III cntd: Other plastic surgical techniques include the following:

Muscle (laps: These are generally reliable, but may result in functional loss.

(a) The gastrocnemius myocutaneous llap: this provides particularly good cover round the knee and in the proximal third of the tibia. Either the medial or lateral head may be used. (The muscle belly is isolated from soleus. its attachment to the Achilles tendon divided, and it is freed from its other head before the Hap is swung.)

(b) The soleal myocutaneous llap: this may be used for cover in the middle third of the tibia.

(The muscle is detached I cm distal to its musculotendinous junction, transposed, and anchored distally.) Added length may be obtained by making several transverse incisions in its sheath. At a suitable time, its outer surface may be covered with split skin grafts.

Free microvascular llaps: The commonest and most useful sources are from the latissimus dorsi or rectus abdominis. The techniques are highly specialised, and careful planning must extend to dealing with the secondary defect. Failure is generally due to vascular problems or infection at the recipient site.

Where hone grafting is required this should be carried out as soon as it is safe to do so. In the case of Type / and Type II open fractures. this can be considered 2-3 weeks after wound healing In the case of Type III open fractures. grafting should be delayed for 6 weeks after healing has been obtained. Where there is extensive bone loss, future reconstruction may be possible using an llizarov bone transport technique.

Type ¡lie open fractures have the highest failure and amputation rate, due to vascular difficulties or infection. In handling these cases the fracture must be soundly fixed and any arterial repair (e.g. by an interpositional graft) achieved within -MS hours: the vascular problem should be dealt with by an experienced vascular surgeon, and not delegated. Prophylactic fasciotomies should be carried out.

10. Degloving injuries (b): The skin may remain unbroken (2 in Frame 9). in which case the limb feels like a Hind-containing bag. owing to the presence of an extensive haematoma between the skin and fascia. If the skin is torn (3 in Frame 9), the effect is the creation of a large Hap of lull-thickness skin. In either case, massive sloughing is likely unless the injury is properly managed. A number of plastic surgical procedures are available:

1. If the skin is in good condition it may be de-fatted and re-applied immediately as a full thickness graft (although failure is not uncommon).

2. If the skin is damaged, split skin grafts may be taken from it (prior to its excision); these may be used immediately if the site is suitable, or stored for a secondary procedure.

3. The llap may be marked for later orientation and excised. After refrigeration storage in a sterile container (storage temperature is important), it is replaced after 1-2 weeks as a single sheet graft, after the deeper layers have been removed using special equipment.

In any open injury it is vital to keep in mind the risks of serious, life-threatening infections, particularly tetanus and gas gangrene, and the appropriate protective measures must be taken.

9. Degloving injuries (a): In a degloving injury, an extensive area of skin is torn front its underlying attachments and thereby deprived of its blood supply. In the hand or arm it is commonly caused by the limb being crushed between rollers (I): in the leg it may result from the shearing effect of a vehicle wheel passing over the limb in a run-over accident.

11. PRINCIPLES OF INTERNAL FIXATION AND COMMON FIXATION METHODS __

When it is intended lo implant materials for the treatment of fractures, the following criteria must be satisfied:

1. Freedom from tissue reaction: It is self-evident that if foreign material is being implanted in the tissues it should be biologically inert, and not give rise to toxic reactions, local inflammatory changes, fibrosis, foreign body giant cell reactions, etc., which in turn are likely to produce local pain, swelling and impairment of function. There is evidence of an extremely low but apparently clear incidence of local, and possibly distal, metal-induced neoplasia. In consequence, in the younger patient (under age 40). internal fixation devices are removed routinely once they have served their purpose.

2. Freedom from corrosion: Implanted materials should not corrode. Where stainless steel is used it should be of an accepted grade and free from impurities; steps should be taken to avoid the initiation of corrosion problems by fretting occurring at the point of contact between the separate components of an implant. It is essential to avoid electrolytic degradation, and in practice this means that if more than one implant is used at the same side (e.g. a plate and screws), identical materials are employed.

3. Freedom from mechanical failure: Implants must satisfy the purposes for which they are intended. To withstand the forces to which they will be subjected demands a satisfactory compromise between the materials used and the design of the implant. In the treatment of fractures, implants generally must have great mechanical strength in association with small physical bulk: consequently most are made of metal. Of the suitable metals, the most frequently employed are:

• Certain stainless steels

• Alloys of chromium, cobalt and molybdenum (e.g. Vitallium " . Vinertia®

The chrome-cobalt alloys are biologically very inert, but are difficult to machine so that most implants, including screws, are microcast using the lost wax technique; this adds to their cost. The stainless steels are less inert, but are easier to machine and are cheaper. In Ihe case of titanium, the favourable combination of high strength, light weight, high fatigue strength, low modulus of elasticity and relative inertness, allows the fabrication of thinner plates and stronger intramedullary nails. It also produces fewer artefacts in CAT and MRI scans, allowing for example, earlier and better detection of avascular necrosis in femoral neck fractures.

In certain situations other materials are sometimes used. e.g. in fractures of the femur in the region of the stems of hip replacements it is possible to employ nylon plates held in position with nylon cerclage straps. At the ankle, biodegradable plastic dowels may be used to treat certain malleolar fractures, and have the advantage that their slow absorption obviates any need for their later removal. Sensitivity to these implants (in the form of a low grade inflammatory response) is. however, a not uncommon occurrence. Where it is desirable to have a certain amount of flexibility in a plate to encourage the formation of some external bridging callus, carbon libre plates arc sometimes used.

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  • s
    What is a technically open fracture?
    3 years ago
  • Bingo
    Which materials i must i use to dress an ipen fracture?
    1 year ago

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