The nurse is planning care for an 11-year-old admitted for surgical treatment of a fractured femur

The four AO (Arbeitsgemeinschaft für Osteosynthesefragen [Association for Osteosynthesis]) principles, in their basic form, have governed the society’s approach to fracture management for decades. [5] They are as follows:

• Anatomic reduction of the fracture fragments - For the diaphysis, anatomic alignment ensuring that length, angulation, and rotation are corrected as required; intra-articular fractures demand anatomic reduction of all fragments

• Stable fixation, absolute or relative, to fulfill biomechanical demands

• Preservation of blood supply to the injured area of the extremity and respect for the soft tissues

• Early range of motion (ROM) and rehabilitation

Preparation for operative intervention

Detecting and adequately addressing all other injuries, including comorbidities and preexisting medical conditions, is essential. If patients have multiple medical problems, consult an internal medicine specialist and/or anesthesiologist before performing any operative intervention.

Prophylactic antibiotics (cefazolin, 1-2 g) should be administered prior to incision. If the patient is allergic to penicillin, clindamycin can be administered. Patients with open fractures should be given appropriate antibiotic prophylaxis (see Elements of Initial Fracture Management). There is no evidence to support continuing prophylactic antibiotics beyond 24 hours postoperatively. [43]

Open reduction and internal fixation

The objectives of open reduction and internal fixation (ORIF) include the following:

• Adequately exposing the fracture site

• Minimizing soft-tissue stripping

• Obtaining a reduction of the fracture

• Stabilizing and maintaining the reduction that has been achieved

Kirschner wires

Kirschner wires (K-wires) are commonly used for temporary and definitive treatment of fractures. However, K-wires resist only changes in alignment; they do not resist rotation, and they have poor resistance to torque and bending forces. K-wires are commonly used as adjunctive fixation for screws or plates and screws that involve fractures around joints.

When K-wires are used as the sole form of fixation, they are supplemented by casting or splinting. The wires can be placed percutaneously or through a miniopen mechanism. K-wire fixation has been used for small fragments in metaphyseal and epiphyseal regions, especially in fractures of the distal foot, wrist, and hand (eg, Colles fractures) and in displaced metacarpal and phalangeal fractures after closed reduction. [23] K-wires are also commonly used as adjunctive therapy for many fractures, including patellar fractures, proximal humerus fractures, olecranon fractures, and calcaneus fractures.

Plates and screws

Plates and screws are commonly used in the management of articular fractures. This use demands an anatomic reduction of the fracture fragments and allows for early ROM of the injured extremity. Plates provide strength and stability to neutralize the forces on the injured limb for functional postoperative aftercare (see the images below).

Plate designs vary, depending on the anatomic region and size of the bone the plate is used for. All plates should be applied with minimal stripping of the soft tissue.

Plates may be divided into five types on the basis of their main functions, as follows [5] :

• Buttress (antiglide) plates

• Compression plates

• Neutralization plates

• Tension-band plate

• Bridge plates

Locking plates or fixed-angle devices are also helpful.

Buttress plates encourage compression and counteract the shear forces that commonly occur with fractures that involve the metaphysis and epiphysis. These plates are commonly used with interfragmentary screw fixation. The buttress plate is always fixed to the larger main fracture fragment but does not necessarily require fixation through the smaller fragment, because the plate buttresses the small fragment into the larger fragment. To achieve this function requires appropriate plate contouring for adequate fixation and support.

Compression plates counteract bending, shear, and torsional forces by providing compression across the fracture site via the eccentrically loaded holes in the plate. These plates are commonly used in the long bones, especially the fibula, radius, and ulna, and in nonunion or malunion surgery.

Neutralization plates are used in combination with interfragmentary lag-screw fixation. The interfragmentary compression screws provide compression at the fracture site. This plate function neutralizes bending, shear, and torsional forces on the lag-screw fixation, as well as increases the stability of the construct. Neutralization plates are commonly used for fractures involving the fibula, radius, ulna, and humerus.

Bridge plates are useful in the management of multifragmented diaphyseal and metaphyseal fractures. Achieving adequate reduction and stability without disrupting the soft-tissue attachments to the bone fragments may be difficult and requires skill in the use of indirect reduction techniques. Care should be taken to obtain correction of rotation, length, and alignment with bridge plating.

A tension-band plate technique converts tension forces into compressive forces, thereby providing absolute stability. An example of this technique is the use of a tension-band plate for fixation of a transverse olecranon fracture.

A locking plate acts like an internal fixator. [48] There is no need to anatomically contour the plate onto the bone; consequently, bone necrosis is reduced, and a minimally invasive technique is possible. Locking screws directly anchor and lock onto the plate, thereby providing angular and axial stability. These screws are incapable of toggling, sliding, or becoming dislodged, thus reducing the possibility of a secondary loss of reduction, as well as eliminating the possibility of intraoperative overtightening of the screws.

The locking plate is indicated for poor-quality bone (ie, osteoporotic fractures), for short and metaphyseal segment fractures, and for bridging comminuted areas. These plates are also appropriate for metaphyseal areas where subsidence may occur or prostheses are involved. [49] Locking plates can only hold a reduction that has already been obtained.

Intramedullary nails

The use of intramedullary nails in fracture management has been widely accepted. These nails operate like an internal splint that shares the load with the bone and can be flexible or rigid, locked or unlocked, and reamed or unreamed.

Locked intramedullary nails provide relative stability to maintain bone alignment and length and to limit rotation. Ideally, intramedullary nailing allows for compressive forces at the fracture site, which stimulates bone healing. Intramedullary nails are commonly used for femoral and tibial diaphyseal fractures (see the image below) and, occasionally, humeral diaphyseal fractures. The advantages of intramedullary nails include minimally invasive procedures, early postoperative ambulation, and early ROM.

Imaging for evaluation of results

C-arm fluoroscopy is valuable and often necessary in the OR to provide for and to evaluate the results of internal fixation before the patient leaves the surgical suite. Alternatively, portable radiography can be used if multiple radiographic images are not anticipated to be necessary. All staff within the operating suite should be protected from radiation, either with aprons or with lead shields, while fluoroscopy is in use. [50]

External fixation

In 1907, the Belgian physician Albin Lambotte developed the technique of external fixation for the management of fractures. [51] External fixation provides fracture stabilization at a distance from the fracture site, without interfering with the soft-tissue structures that are near the fracture. This technique not only provides stability for the extremity and maintains bone length, alignment, and rotation without requiring casting but also allows inspection of the soft-tissue structures that are vital for fracture healing, as well as subsequent wound care.

Indications for external fixation (temporarily or as definitive care) are as follows:

Open fractures that have significant soft-tissue disruption (eg, type II or III open fractures)

• Soft-tissue injury (eg, burns)

• Pelvic fractures (see the first image below)

• Severely comminuted and unstable fractures

• Fractures that are associated with bony deficits

• Limb-lengthening procedures (see the second image below)

• Fractures associated with infection or nonunion

Polytrauma: early total care vs damage-control orthopedics

Soft-tissue injuries and potential open wounds are inflammatory foci that behave much like an endocrine organ by releasing mediators and cytokines both locally and systemically, leading to a systemic inflammatory response. Further surgical insult (ie, femoral nailing for a femur fracture) can aggravate this mediator response, resulting in a further immunologic response, known as the "second hit" phenomenon. [52] This, in turn, may exacerbate the patient’s clinical status and can lead to further morbidity as well as mortality.

Early total care is important; several studies have documented the advantages of early fixation of long-bone fractures, especially femur fractures. [52, 53, 54] These advantages include early mobilization with improved pulmonary function, shorter time on a ventilator, reduced morbidity and mortality, and easier nursing care.

Early definitive surgical care should be considered only in stable patients who have been adequately resuscitated, whereas those who are unstable should undergo damage-control orthopedics (DCO). The DCO concept refers to early debridement of surgical wounds with minimally invasive temporary fixation of long-bone fractures and dislocations. External fixator pins should be placed outside the zone of injury and should avoid sites of planned future incisions.

DCO should be considered in patients who are hemodynamically unstable or those with hypothermia, an abnormal base deficit, or blood-clotting abnormalities/pulmonary complications. No single test is available yet to determine which patients are at risk for a major systemic inflammatory response following trauma; however, concern should be high in patients with Injury Severity Scale (ISS) scores higher than 40, those with ISS scores higher than 20 who have thoracoabdominal injuries, and those who have moderate-to-severe head injuries, among others. [5, 43]

Moderate-quality evidence exists that DCO results in shorter operating times and less blood loss than early total care. [43] Although studies have not yet shown that DCO results in a decrease in mortality in a broad population of trauma patients, it may be that the benefit is primarily in a subset of severely injured patients. [43] Even if an initial DCO approach is followed, definitive management should be performed within 7 days from injury, once the patient is stabilized, to minimize the risk of infectious complications.

Minimally invasive percutaneous plate osteosynthesis

Krettek et al were prominent in developing the concept of minimally invasive percutaneous plate osteosynthesis (MIPPO) with indirect reduction. [55] This technique involves the use of anatomically preshaped plates and instrumentation to safely and effectively insert the plate percutaneously or through limited incisions. Various plates, clamps, and other devices aid in the reduction of the affected bones.

Certain advantages of MIPPO may include faster bone healing, reduced infection rate, decreased need for bone grafting, less postoperative pain, faster rehabilitation, and more aesthetic results. Some disadvantages may include difficulty with indirect reduction, increased C-arm exposure, malunion, pseudoarthrosis through diastases, and delayed union with flexible fixation in simple fractures. [49]

Biologic aids for fracture healing

The use of biologic agents that aid in fracture healing will be commonly used in fracture management. Currently, autologous and cadaveric bone grafts are used in fracture management. Autologous cancellous bone grafts are used to fill defects and to provide stimulus for growth. Cadaveric cortical bone grafting is commonly used to provide diaphyseal structural support and to aid in filling large diaphyseal deficits.

A number of organic and synthetic materials have been used to promote fracture healing. These include hydroxyapatite, tricalcium phosphate, and calcium sulfate. Other biologic agents that have been recognized as stimulators of fracture healing include peptide-signaling molecules (eg, bone morphogenic protein [BMP], transforming growth factor [TGF] beta, gene family fibroblast growth factor [FGF], and platelet-derived growth factor [PDGF]) and immunomodulatory cytokines (interleukin [IL]-1 and IL-6). Some of these biologic agents have been gaining in popularity. BMP, for example, is now commonly used in spine surgery to facilitate interbody fusion.