OPEN FRACTURE

Orthopedic Teaching Cases 2023, Jan, 20 | 12:00 am

OPEN FRACTURE

1. Describe what you see and your initial management in the emergency department.

This is a clinical photograph revealing an open tibial fracture. There is a large transverse wound over the medial border of the tibia with exposed bone protruding. There is obvious periosteal stripping and contusion to the surrounding skin.

This patient requires management in accordance with ATLS principles as it is likely a high-energy injury with potential for other more life-threatening injuries to be present.

Specifically for the open fracture, I would perform a full neurovascular examination of the affected limb. I would remove any obvious contamination from the wound, photograph it, and then cover it with a saline-soaked swab. I would provide analgesia, and splint the limb as well as obtain radiographs if not already performed.

I would give antibiotics as per local microbiology protocols (the BOAST guidelines suggest cefuroxime 1.5 g IV) and assess the need for tetanus prophylaxis.

2. When should the patient go to theatre and what will you plan to do?

The current consensus favours prudent early surgery within the first 24 hours. The old '6-hour rule' was based on animal experiments from the 1890s, and the wellknown Lower Extremity Assessment Project (LEAP) study* found no difference in infection rates when open fractures were managed within 6 hours or 24 hours. The BOAST guidelines recommend urgent surgery if there is a vascular injury or the wound is heavily contaminated by marine, agricultural or sewage matter.

Assuming there is no vascular injury, this injury is best managed during daytime hours with combined orthopaedic and plastic surgery input. The wound will be thoroughly debrided in a systematic fashion from outside to in, including skin, fat, fascia, muscle and bone. Non-viable skin should be excised, but any skin that is of dubious viability may be left for later assessment/debridement, unlike necrotic muscle which is implicated in infection and must be removed. Muscle can be assessed utilising the 4 Cs (colour, consistency, contractility, cut [does it bleed?]).

I would deliver the bone ends and debride these, in addition to removing any devitalised bone which fails the 'tug test'. I would wash out the wound and fracture with 6 litres of warmed normal saline. I would then stabilise the fracture provisionally using an external fixator or definitively with an intramedullary nail if I agree with my plastic surgery colleague that definitive surgery is safe and wound closure or coverage can be achieved. Antibiotics would be given at the time of surgery and continued for 72 hours or until wound closure, whichever occurs soonest.

3. What is your biggest concern in the postoperative period and how would you monitor for this?

With any high-energy fracture, particularly of the tibia, I would have a high index of suspicion for compartment syndrome. Although the open fracture has created a rent in the fascia, this in no way precludes the development of compartment syndrome. Diagnosis of compartment syndrome is a clinical one, but this requires a high index of suspicion in all staff members looking after the patient. Patients who are unconscious or obtunded warrant continuous pressure monitoring with a slit catheter as used for arterial pressure monitoring. Continuous pressure monitoring of the anterior compartment is a useful adjunct to clinical diagnosis, whereby the ΔP is calculated by subtracting the intracompartmental pressure from the diastolic blood pressure. A persistently low ΔP, that is, <30 mmHg, is diagnostic of early compartment syndrome. A caveat to continuous pressure monitoring of the anterior compartment is that one must remain vigilant to the possibility of compartment

*LEAP study: This was a multicentre prospective observational study which has published numerous papers since its conception. It identified 601 patients with severe, limb-threatening lower extremity injuries from eight level I trauma centres in the United States and followed them up prospectively for a number of outcomes. Several publications have come from the data collected and the main findings include:

• No difference in infection rate for open fractures managed within 6 hours or within 6 to 24 hours.

• No scoring system was predictive of the need for amputation.

• Loss of plantar sensation is not an absolute indication for amputation.

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Open Fracture

syndrome developing within the deep posterior compartment, which may give falsely reassuring readings in the anterior compartment.

4. How would you treat compartment syndrome?

I would perform an emergency two-incision, four-compartment fasciotomy of the lower leg. (See Chapter 73.)

5. How soon should you aim for soft tissue coverage and what options are available?

The BOAST guidelines suggest that soft tissue coverage is ideally performed within 72 hours. Options include primary closure, which is an acceptable option when there has been a thorough debridement and soft tissue coverage is possible without tension.

Other options are described by way of the plastic surgery reconstructive ladder. This includes primary closure and healing by secondary intention, escalating to a free flap.

If an open wound involves loss of skin and subcutaneous tissue, but has a base of healthy muscle, fascia, or tendon sheath, granulation tissue will form on the base and a split-thickness skin graft (STSG) can be applied, or the wound can be allowed to heal by secondary intention.

Bare bone, exposed blood vessels, nerves and tendons (without paratenon) all are harmed by desiccation and do not support granulation tissues and STSG. These tissues should not be left exposed, and should be kept moist with appropriate dressings prior to definitive cover.

Reconstructive options	Examples
Healing by secondary intention	-
Primary closure	-
Delayed primary closure	-
STSG	-
FTSG (full thickness skin graft)	Small grafts: Medial forearm and volar wrist crease Large grafts: Lower abdomen and groin
Local flaps	Axial flaps, rotational flaps, rhomboid flaps, V-Y advancement flaps
Rotational muscle flaps	Gastrocnemius rotational flap, soleus rotational flap
Free flaps	Fasciocutaenous/musculocutaneous/osteocutaneous

Regarding flaps for soft tissue coverage of a tibial fracture specifically, the following acts as a guide to treatment options:

• Proximal third tibial defect - Gastrocnemius rotational flap

• Middle third tibial defect - Soleus rotational flap

• Distal third tibial defect - Free flap

• Large defect - Latissimus dorsi

• Smaller defect - Radial forearm

- Sural artery fasciocutaneous flap

6. How can you grade open fractures?

Open fractures are most commonly graded using the Gustillo and Anderson classification. The original classification from 1976 was based on their experience of

1025 long bone open fractures. Their initial paper proposed a classification system split into grade I, grade II and grade III, but grade III open fractures were highly variable in their pattern of injury and outcomes such as infection. In 1984, Gustillo, Mendoza and Williams modified their initial classification system to include three subtypes in the grade III open fracture and is what orthopaedic surgeons today refer to as the Gustillo and Anderson classification.

Grade I	An open fracture with a clean wound <1cm
Grade II	An open fracture with a wound >1cm but without extensive soft tissue damage or periosteal stripping
Grade III	The following situations warrant automatic grade III classification:

• High-energy injury

• Gunshot wound

• Heavy contamination

• Farmyard contamination

• Open segmental fracture

• Delay to treatment >8 hours

• Arterial injury requiring repair

IIIa - An open fracture with extensive soft tissue damage but adequate soft tissue coverage

IIIb* - An open fracture with extensive soft tissue loss and periosteal stripping

IIIc - An open fracture with an associated arterial injury requiring repair

*There is confusion amongst trainees when it comes to the IIIb subtype of open fractures.

In 1994, Brumback and Jones, after conducting a survey of 245 orthopaedic surgeons, concluded that 'interobserver agreement with use of the Gustilo-Anderson classification system for open fractures is moderate to poor'.

In response to that paper, Gustilo wrote in a letter to the editor of the Journal of Bone and Joint Surgery ( American volume ):

Soft-tissue injury is probably the number-one factor in the classification of open fractures. With type I, II, and IIIA fractures, there is enough soft-tissue coverage for delayed primary skin closure or skin-grafting overlying the bone to be recommended. With type IIIB open fractures, after debridement and irrigation of the fracture, the use of local or free vascular flaps is essential because of extensive softtissue injury, exposed bone, and periosteal stripping.

More interestingly, as a reply to that letter, Brumback and Jones wrote in the same journal:

With regard to soft-tissue closure, although type IIIB injuries often need full-thickness soft-tissue coverage, it is only in this individual classification that the type of soft-tissue closure helps the examiner to determine the type of open fracture. Even though Dr. Gustilo states that local or freely vascularized flaps are essential in the treatment of type IIIB fractures, this criterion was not part of the definition of the IIIB subtype published in 1984. This exemplifies another criticism of the classification of Gustilo and Anderson: it has been so widely published,

frequently with modifications, that even the specific definitions of each type are no longer universal.

To summarise, when describing the original classification, one frequently quotes the 1984 open fracture classification which is in fact a modification of the 1976 paper. Type IIIb is described in the previous table and the need for a flap is not part of the classification system