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Amputee
Bi-Lateral Amputee Wins Aeromedical Certification
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Veteran Pilot Gets Certified to Fly Despite Near-Fatal Crash Injuries. A former airline pilot who lost both hands in an auto accident, was fitted with two remarkable artificial limbs. Later, he applied, was tested by the FAA and given the green light by FAA physicians to fly. The Federal Aviation Administration certified and issued a Third-Class medical certificate to an airman with two prosthetic devices for arms, a "first" for the agency. This case involved a veteran commercial pilot who had suffered a major automobile accident two years earlier. After extensive rehabilitation, and through the use of innovative prostheses, he decided to regain his flying status, applying to the FAA for a medical certificate. Through the Special Medical Issuance process, the FAA Office of Aviation Medicine is able to assess, on an individual basis, the appropriateness of issuing medical certificates to airmen who do not meet medical certification standards. This 47 year-old male pilot was the holder of a First-Class FAA medical Certificate. |
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He was working as an airline pilot and had more than 20,000 hours of flight experience on various types of aircraft including Douglas Skyhawk (A-4), Cessna Citation (CE-500), Grumman Stoof (GS-2), Catalina (CV-PBY), Fairchild (C-199), Boeing (B-737), and McDonnell/Douglas (DC-9). He had a history of mild to moderate arterial hypertension controlled with medication (Atenolol), and diskectomy for a herniated disk. In September of 1993, he was involved in a high-speed single vehicle roll-over accident at a race track. It took approximately 30 minutes to extricate him at the scene, and about 60 minutes before he was finally flown to a hospital. He was conscious at the scene with an initial Glasgow coma score of 12. He was admitted to emergency service with a diagnosis of: 1) head injuries, 2) complete traumatic amputation at the wrist of the left upper extremity, and 3) near total amputation of right upper distal forearm with major neurovascular injury. A computerized tomography (CT) scan of his head revealed a right temporoparietal intraparenchymal hemorrhage with no shift. |
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An intracranial pressure (ICP) bolt was placed for monitoring during the prolonged surgery related to his traumatic amputations and closed head injury. The surgery report indicated: 1) Complete amputation of his left wrist, elevated compartment pressure to 70-80 mmHg consistent with compartment syndrome, and 2) near complete amputation of his right forearm with extensively devitalized musculature to approximate one-third, avulsion injury of the palmar and thenar musculature and thrombosis of the radial and ulnar arteries. His right forearm was amputated because it was considered non-salvageable.
Three weeks after the accident he was discharged from the hospital and transferred to a rehabilitation facility. Upon admission, he was reported to have a moderate cognitive deficit in memory, reasoning, and judgment. He underwent physical therapy and speech therapy. One week later he was discharged and transferred to an amputee clinic. He was fitted with Otto Bock myoelectrically-controlled upper extremity (right and left) prostheses.
In March of 1994, this pilot requested the issuance of a Third-Class FAA medical certificate, which was denied because of concerns about his cognitive deficits after the accident. At that time, the airline for which he worked determined that the airman had a permanent medical disability. In May of 1994, he requested reconsideration of his case by the FAA but the certification denial was sustained. In October of 1994, he obtained a commercial glider pilot license (a medical examination is not required for a glider license).
A month later, once again he requested reconsideration of his case for airman medical certification and he was instructed by FAA to:
1) Undergo a comprehensive follow-up neuropsychological evaluation to assess the current status of his cognitive functioning,
2) complete an evaluation of his prostheses in the altitude chamber at the FAA Civil Aeromedical Institute (CAMI),
3) take a Medical Flight Test (Third-Class), and
4) undergo a follow-up cardiovascular evaluation because of his documented hypertension (controlled with medication).
The results of his neuropsychological evaluation conducted 14 months after the accident were reported as within normal limits. As part of his evaluation at CAMI, he first demonstrated the normal operation of his prostheses. He was then instructed to take them off to be tested in the altitude chamber, using the following flight profile: 1) Ascent from ground level (GL) to 40,000 feet at a climb rate of 6,000 ft/min and descent to GL at 6,000 ft/min. Following this exposure, he was asked to put on the prostheses and test their operation. 2) Ascent from GL to 8,000 feet and decompression to 40,000 within 20 seconds, followed by a descent to GL at 6,000 ft/min. Following this exposure, he was asked to put the prostheses on and test their operation. Once the testing of the prostheses (only) was completed, he was required to undergo altitude chamber evaluation while wearing the prostheses.
The flight profile used for this purpose was as follows:
Ascent to 6,000 ft at a climb rate of 3,000 ft/min to perform an ear and sinuses check,
descent to 2,000 ft at a rate of 3,000 ft/min to perform an ear and sinuses check,
ascent to 8,000 ft at a rate of 3,000 ft/min,
rapid decompression to 18,000 ft over a 10-12 second period,
ascent to 25,000 ft at a rate of 3,000 ft/min, and
descent to ground level at a rate of 3,000 ft/min. In April of 1995, he was subject to a special medical flight test, which he successfully completed.
BACKGROUND
Amputations
The National Center for Health Statistics of the US Department of Health and Human Services estimates that there are approximately 4 million amputees in the United States. Based on their latest National Health Discharge Survey in 1992, during that year there were about 10,000 new upper amputees (70% males and 30% females) and 116,000 new lower amputees (63% males and 37% females). The primary cause of amputation is vascular and circulatory disease, and 89% of these amputation are performed on people over 50 years old (half of them as a result of diabetes). Other causes of amputation are trauma, bone cancer, and congenital deformities. The FAA has medically certified a total of 17 pilots (3 Second-Class and 14 Third-Class) with unilateral amputated hands (8-left and 9-right). These unilateral hand amputees, who otherwise met the aeromedical certification standards, were certified by the FAA after demonstrating their ability to safely operate an aircraft.
Prostheses
The development of the first prostheses (artificial body parts) probably coincided with the beginning of mankind. Early prostheses permitted the restoration of some functionality (following the loss of a limb or a part of it) and enabled individuals to regain some level of physical independence. The earliest known limb prosthesis was a copper and wooden leg unearthed in Italy, that is believed to have been made about 300 Initially, artificial limbs were made of materials found in the surrounding environment, such as wood and bone. Subsequently, artificial limbs evolved both in design and materials, including iron and alloys. Following World War II, the availability of new materials, designs, and fitting techniques resulted in greatly improved prostheses for amputees. Advancements in bioengineering have also contributed significantly to the development of new prostheses that are able to compensate more effectively for the functional sequelae left by an amputation. In the near future, it can be expected that amputees will be able to:
Use their own muscles and nervous system for controlling prosthetic limbs;
sense pressure (tact), heat, and cold in their prostheses;
3) use prostheses with motion capabilities that reproduce those of their biological counterparts; and
4) obtain customized prostheses that are cosmetically indistinguishable from their biological counterparts. Out of the 17 pilots medically certified by the FAA with unilateral hand amputations, 11 were certified using prostheses (5-left and 6-right).
The type of prosthesis used by the pilot being discussed is primarily for below elbow amputees, and it is held in place by a partial vacuum. The inner surface is individually molded to fit the forearm stump to provide a tight seal. The prosthesis is easily attached by pushing the forearm stump firmly into the socket to force the air out, and easily removed by pushing on the check valve (located on the distal end of the socket) and pulling back the forearm stump. The myoelectric system uses the wrist flexor and extensor muscles to open and close the hand. Pronation and supination of forearm stump controls pronation and supination of the prosthetic hand (rotation range of about 180 degrees).
AEROMEDICAL CONSIDERATIONS
A comprehensive review of the open medical literature did not yield a single published case of an active pilot with bilateral hand amputation using prostheses.
This case was unique due to several factors:
It involved a highly motivated pilot with over 20,000 hrs of total flight time experience;
The pilot suffered head trauma that resulted in temporary cognitive deficits;
The pilot suffered a traumatic bilateral amputation of his hands;
The pilot used bilateral myoelectrically-controlled upper extremity prostheses. FAA's previous certification experience involved only unilateral hand amputees with a single prosthetic replacement.
The first concern in dealing with the medical certification of this pilot was his cognitive deficit (memory, reasoning, and judgment) reported after the accident. However, the results of the neuropsychological evaluation requested by the FAA (performed 14 months after the accident) indicated that his intellectual skills on both a verbal and non-verbal levels, were normal. Therefore, these favorable results lessened the FAA's concern about his cognitive abilities in the context of operating a general aviation aircraft.
The second area of concern was the uncertainty about the pilot's ability to manually operate an aircraft (especially during an emergency) with his myoelectrically-controlled bilateral hand prostheses. This concern was favorably resolved after his successful completion of a special medical flight test.
The third area of concern involved the design characteristics of the prostheses. Since this type of prosthesis is held in place by creating a partial vacuum between the forearm stump and the socket of the prosthesis, there was a possibility that during exposure to a hypobaric environment (flying an unpressurized aircraft or during a rapid decompression in a pressurized aircraft) the prosthesis could fall off if the partial vacuum was lost as a result of expanding trapped air between the forearm stump and the prosthesis. It was also unknown if the prostheses themselves could be damaged during exposure to high altitude. Furthermore, it was not known if the pilot could effectively and efficiently operate the oxygen equipment (mask and regulator) during a simulated inflight emergency (rapid decompression) using his prostheses. All of these questions were answered favorably during the tests performed by the FAA in the altitude chamber.
Taking into account this pilot's flying experience, his strong motivation to continue flying, his successful completion of all the special tests requested (neuropsychological, medical flight test, and altitude chamber), and his compliance with all other applicable medical certification standards (including a waiver for his controlled hypertension), the FAA decided to grant his request for the issuance of a Third-Class medical certificate with a Statement of Demonstrated Ability (SODA) that required him to wear his artificial limbs when piloting an aircraft.
REFERENCES
1. Aerospace Medical Association. Sixty Years of Aerospace Medicine - Database. Volumes 1-60.
2. Federal Aviation Administration. Consolidated Airman Information System (CAIS). Aeromedical Certification Division 1995.
3. International Wheelchair Aviators Association. Escondido, California.
4. Vital & Health Statistics, Detailed Diagnosis and Procedures, National Health Discharge Survey, 1992, Series 13, #118. FIGURE 1. Myoelectrically controlled prostheses used by airman applicant.
Dr. Mera Ospina is the Chief Medical Officer of the Colombian National Police's Air Service.
Dr. Antuñano manages CAMI's Aeromedical Education Division.
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