Author’s comments: The information in this article was compiled from the most current medical literature available, as well as the clinical experience of the author. This is meant for informational purposes only. The adjuster or case manager should first follow existing company protocols.|
TREATMENT OF CRUSH INJURIES OF THE FOOT
The initial care of a crush injury of the foot often determines the ultimate clinical outcome. There have been several long term studies that document that if specific steps are followed in the immediate medical care of a foot crush injury, the patient will have a better chance of good functional recovery, even if there are fractures and extensive soft tissue injury. A study by Myerson and Henderson, workers with mangling-type injuries were followed for an average of 3.3 years and found that by following specific protocols (described in this article) 46% had good functional recovery, 29% with “fair” results, and 25% with poor results. This was an improvement of clinical outcomes from earlier studies. Regardless, this type of injury presents a significant challenge in occupational medical care and workers compensation claim management because of its potential for prolonged morbidity.
In 2000, the BLS recorded 1,509 foot and toe injuries serious enough to cause lost workdays in industrial workplaces. This type of injury is probably under reported because a separate study performed by the National Safety Council in 1997, documented 180,000 injuries for that year with an average medical care cost of $6000 per injury. A Bureau of Labor Statistics (BLS) study of foot injuries found 75 percent of the accidents occurred when workers were not in compliance. The U.S. industrial market for safety shoes and boots, rubber or plastic boots, and foot and leg guards to prevent these injuries is estimated at nearly $1 billion. This is approximately $70 is spent per employee on foot protection per year.
Etiology of traumatic foot injuries:
Primary causes for crush foot injuries are from falling heavy objects, motor, industrial or railway vehicles rolling over the foot, and crush injuries from industrial equipment. There are varying degrees of tissue injury depending on the weight or force. The most serious injuries involve ligament tears of the plantar fascia, amputations, degloving or avulsion of soft tissue and multiple fractures. Another serious complication is the development of a compartment syndrome in which there is so much swelling and internal pressure within the foot that circulation is compromised with soft tissue and nerves are lost.
Management of Crush Injuries
There needs to be an aggressive and systematic approach to treating extensive soft tissue injuries of the foot. When the person presents to an emergency room with a swollen or mangled foot from a crush injury, there needs to be several steps taken urgently for determining the extent of the injury and beginning appropriate treatment:
Much of the above treatment occurs when the injured employee is transferred to the ER. The adjuster and case manager, when notified of a serious foot injury, should begin monitoring the situation to make sure that there is aggressive approach to treatment.
Special Issues About Crush Injuries of the Foot
Fracture Types that Heal Poorly:
There are several fracture types that can also lead to long term disability. Fractures with the highest risk of poor healing or non-union involve the Lisfranc joint of the foot (tarsometatarsal), talar and compression fractures of the calcaneal bone. These fractures usually occur when the person falls from a distance, landing on the feet. If there is a suspicion of any of the above fractures, there should be immediate referral to a podiatrist or orthopedic physician because rapid reduction and/or stabilization by open fixation is needed to prevent bone necrosis. This is also true of a navicular stress fracture which is usually associated with sports injuries.
Importance of Diabetes in Healing of a Crush Injury
There needs to be special mention of an injured employee with diabetes who sustains a crush injury of the foot. Persons with poorly controlled disease have a significant risk of preexisting and permanent microvascular (small vessel) and macrovascular (large arterial vessel) circulation problems. Health care professionals have long recognized the relationship of diabetes, decreased circulation and development of infection and ischemic ulcers of the foot. A crush injury greatly increases the risk of further compromise of blood flow.
Even relatively minor contusions or crush injuries compromises the already decreased circulation, if there is swelling. Severe injuries to the foot of a diabetic patient in which there are complex fractures, compartment syndrome, open wounds or tissue lost places the person at extreme risk for the potential of loss of a portion or all of the foot if circulation is not restored promptly or if infection develops.
The Role of Hyperbaric Oxygen Therapy in Crush Injuries of the Foot
Hyperbaric medicine is not a new medical discipline but with the increased number of mono- and multi-place chambers available in most communities, podiatrists and physicians are finding newer applications for the use of oxygen breathed under pressure (hyperbaric oxygen) as an important treatment modality.
The physical characteristics of any gas, including oxygen, will change when placed under pressure. If the person is breathing a higher percentage of oxygen (above 21%) at sea level, blood levels of oxygen will increase only a small percentage. At normal atmospheric pressures, 97% of blood’s oxygen is carried by red blood cells and 3% is dissolved in blood plasma. In a recompression chamber, oxygen-enriched air, under pressure, will cause a large amount of oxygen to be dissolved in the blood plasma.
The current concept of how hyperbaric oxygen promotes tissue healing is that supersaturated oxygen in plasma will rapidly leave solution and enter the damaged tissue area. Low tissue oxygen levels rapidly develops in a crush area with accumulation of metabolic breakdown products. These substances, like lactic acid, will prevent healing. The hyper-oxygenated blood will reverse this process and allow for chemical processes within the damaged or under-perfused area to return to normal. This promotes cell and new blood vessel growth.
For the patient with a severe crush injury in which there is extensive tissue disruption, post operative skin grafts or internal bone fixation, hyperbaric treatment is ideal for improving the chances of the person to recover with a functional foot. Other patients who may benefit from these treatments include persons with skin ulcers, avulsions, and deep open wounds that do not heal or remain chronically infected. Diabetic patients with foot crush injuries should be considered ideal candidates. Additionally, individuals who develop soft tissue infections and gas gangrene caused by anaerobic bacteria and fungus are also greatly benefited from these treatments.
References used by the author to create this article are available upon request.