Irrespective of burn etiology, joints are rarely involved in burn injuries. Yet, burns can often impair the function of joints. Postburn, joint dysfunction can result from hypertrophy, contraction of scar tissues or graft, activity restriction, or changes in the ligamentous structures. One study found that elbow joint deformities were more common than contractures in other joints, such as the knee, axilla, or hip. ^,

Hinge joints such as the elbow control movement necessary for normal, daily function. The elbow is a key joint for hand function, both because of its role in placing the hand within space and because it transits key nerves and blood vessels for the hand. ^, Contractural defects can impact eating, writing, driving, or even use of a smartphone—all routine activities. ^, Additionally, the poor aesthetic outcome of an elbow contracture postburn can impact patients’ well-being.

The elbow is particularly prone to development of contractures or range of motion (ROM) limitations postburn. The muscle belly of the brachialis muscle crosses the anterior joint capsule of the elbow, rather than a tendon. This muscle can tear in trauma, leading to adherence of the muscle fibers to the joint capsule and scarring. Additionally, blood can irritate the capsule, resulting in fibrosis of the tissue. The interrelationship of the capsule and surrounding ligaments also contributes to the susceptibility to contractures.

Postburn, the elbow joint flexes or folds into a posture of comfort, potentially due to the contractile force difference between the extensor and flexor muscles combined with a loss of voluntary control of muscle movement. With limitations in physical activity postburn and the development of scar tissue, deformity of the elbow can form. Lack of proper positioning during recovery could also contribute to the development of an elbow joint defect postburn. In the elbow, flexion contracture is the most commonly encountered deformity and more functionally limiting than elbow extension contractures. ^{, ,} Fortunately, a number of noninvasive techniques have been demonstrated effective at mitigating the development of a contracture.

Splints, orthoses, or casts can reduce the incidence of contractural deformities in the elbow and minimize the need for reconstructive surgery. Thus splinting of the elbow joint and early motion as soon as patient is able are critical to minimizing contracture deformities. To achieve this, a three-point extension splint across the elbow joint or an extension brace may be used to maintain the elbow in full extension. In pediatric patients, serial casting may be necessary due to difficulty with compliance in that patient population.

Post-resuscitation and once the patient is stable, passive motion to maintain the functional integrity of the elbow joint and muscle tone is requisite. Ideally, physical or occupational therapists experienced in working with burn patients should see the patient during the acute phase of care as soon as the patient is resuscitated to formulate an exercise regimen dependent on the amount of joint involved and the injury size and depth. These therapists would then take the joint through exercises as frequently and as intense as the patient can safely tolerate and evolve the exercise regimen as the patient progresses through the plan of care. Stretching the scar must be done with care lest the tension result in inflammation and reinvigoration of scar formation. Additionally, in patients with burns involving more than the superficial antecubital soft tissues, these techniques may be less effective, and follow-up should be vigilant to determine if surgical intervention is warranted.

Skeletal traction is less commonly used in burn centers but is still a technique to mobilize a contracted elbow. Typically, a Steinmann pin is inserted percutaneously through both cortices at the junction of the distal third and the proximal two-thirds of the radius. With the patient in a supine position, a pulley traction device with a 10- to 15-pound weight can effect a horizontal and then vertical downward pull on the radius by gravity. It is recommended for therapists to do this several times a day.

During the intermediate phase of recovery, compression garments or pressure dressings can be incorporated into the orthotic device. If the patient had recent surgery rendering the use of pressure dressings impossible, airplane splints may be used until sufficiently healed. Pressure dressings should generate a pressure ingredient of 10 to 25 mm Hg to be effective. Less pressure will not reduce tissue swelling or promote softening of the burn scar, whereas greater pressure could restrict blood circulation through the joint, potentially further damaging vessels, muscles, and skin.

In elbow joints that have a persistent deformity despite pressure dressings, splinting, and exercise, or when the functional integrity of the elbow may be in jeopardy, surgical reconstruction may then be warranted. The normal ROM for an unburned elbow is 50 degrees of pronation and supination each and 30 to 130 degrees in the arc of flexion and extension. Patients with less than 100 degrees of flexion-extension capability and those with myotendinous contracture or scarring of muscle fascia should be considered for operative reconstruction. Only surgical intervention can definitively determine the cause of elbow contracture.

Presurgical assessment should determine the following:

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  Extent of contracture and ROM

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  Thickness of scarring

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  Location of the point and axis of joint rotation

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  Availability and size of uninjured skin and identification of donor sites

The most common cause of joint deformity is scar contracture. The surgeon should make an incision in line with the axis of joint rotation and as long as needed to release the joint, taking caution not to injure major vessels and nerves. As the scar tissue is freed, the surgeon should move the joint to ensure maximum elbow extension has been achieved.

After release of the contracture, skin grafts harvested from donor sites can be used. Primary closure is not recommended as insufficient uninjured skin is present to allow for closure. Optimal donor sites include the lower abdomen and the anterior surface of the upper thigh. Elbow extension must be maintained with an orthosis, and pressure dressings used to reduce the possibility of further contracture. Passive stretching and dynamic orthosis can be used once the graft is stable.

In the case of patients with large burn total burn surface areas (TBSAs) or if the elbow joint is exposed during the contracture release, the surgeon may need to use flaps to close the defect. The choice of flap in a burned patient is often dictated by donor availability. Local, regional, or distant flaps from an unburned area may be lifted from the donor site and placed to lengthen the wound. A recent study found that graft take was less than flap take in elbow reconstruction postburn, and the rate of contracture reoccurrence was much higher when grafts were used. It is important to identify the ulnar nerve during flap reconstruction of the elbow, in particular the medial or posterior elbow, to mitigate any sequelae of ulnar nerve impingement or loss.

For small defects in smaller TBSA burns, a common technique is the Z-plasty, in which the surgeon interposes two triangular flaps of 60-degree angles from an unburned area immediately adjacent to the elbow. The donor defect can be closed primarily or grafted.

The three-quarter Z-plasty is another common technique to cover the elbow after surgical release. Also called an interposition flap or a banner flap, the surgeon would design a triangular skin flap of unburned skin adjacent to the elbow, beginning the vertical limb of the flap at the end of the edge of the contracture release. The length of the vertical limb should equal the length of the incision to release the joint. The surgeon will then set the vertical limb at a 90-degree angle to the end of the burn. Measure the width of the burn, and this should be the width of the flap at its midsection. Dissect out the flap, rotate it 90 degrees to cover the wound, and set it in the wound. Use a skin graft to close the sides not covered by the flap.

However, if there is only a limited amount of unburned skin adjacent to the elbow, then the surgeon may rely on using flaps to cover the defect. Flaps are continuously being redesigned and modified, dependent on available vascularity and space. Fasciocutaneous flaps lifted from the upper extremity have been the flap most commonly chosen to cover an elbow joint defect. These flaps may be better suited for smaller contracture defects. Some studies have found propellor flaps to be safe and versatile options for managing contractures of the elbow postburn. ^{, ,} Ultimately, the choice of reconstruction must be made based on the scar pattern and the availability of unburned skin. ^, To minimize the chances of flap failure, the surgeon should try to design a flap that is flexible, thin, and durable enough to withstand repeated flexion and extension while allowing for the ROM requisite for daily life.

Wound care after flap placement generally follows the same principles. The use of splint, brace, or other orthotic device is recommended within 5 days, and passive motion should resume as soon as the patient can safely tolerate.

Reconstruction of the joint capsule may be indicated in rare cases where the cicatricial changes involve the joint capsule. Although elbow arthroplasty is ideally delayed while the patient is managed with therapy to focus on function and ROM, surgical intervention may eventually be a patient’s only option.

Seen in less than 6% of upper extremity burns, heterotopic ossification (HO) can be mistaken for infection or complex regional pain syndrome. The abnormal formation of bone in soft tissue, HO has been demonstrated to be promoted by burn injuries through the release of tumor necrosis factor–α. HO more frequently develops in patients with a prolonged course in the intensive care unit. The anatomic qualities that make the elbow susceptible to contractures also contribute to its susceptibility to developing HO. As a result, the elbow is the joint most often requiring surgical intervention due to HO. ^, Presenting as localized soft tissue pain, erythema, warmth, edema, and progressive loss of motion, HO can be diagnosed via X-ray at least 6 weeks after formation. HO generally presents posteriorly and medially with respect to the olecranon. Additionally, HO often encases the ulnar nerve. In patients where the total ROM of the elbow is less than 50 degrees, function is compromised, and surgery may be warranted. It is important that surgical intervention is planned only when HO is fully matured: defined cortical margins and trabecular markings should be present. Dissection and excision of scarred tissue should be carried out until a significant improvement of elbow extension is observed.

Another complication of burn injury to the elbow is ulnar nerve compression. During surgical intervention during the acute phase of care of the burn, as well in subsequent reconstruction, it is important to protect the ulnar and radial nerves. Ulnar nerve transposition may be warranted to mitigate against cubital tunnel syndrome. This syndrome is the second most common compressive neuropathy, and surgical intervention is warranted if the patient’s condition does not improve with noninvasive modalities. Decompression, endoscopic release, or anterior transposition may be used to treat the condition, with reports differing as to revision rates and no difference in clinical outcomes shown between decompression or release. ^, A recent study found wrapping the ulnar nerve with human amniotic membrane reduced recurrence of paresthesias.