Review Question - QID 4531

A transfemoral level amputation requires the greatest increase in energy expenditure of the amputation levels given, and a Syme amputation the least.

Biologic joints are energy couples. When performing amputation surgery, more proximal amputations, accompanied by the removal of more joints, decreases the ability of patients to walk and live independently. Therefore a Syme amputation would require only a small increase in energy needed for ambulation. Bilateral transtibial amputee patients have an energy expenditure that is 40% above baseline levels. According to Miller's Review text, unilateral transfemoral amputee's require a 65% increase in energy expenditure.

Pinzur et al. retrospectively studied 97 adult patients with diabetes mellitus who underwent Syme ankle disarticulation because of a neuropathic foot with an infection or gangrene, or both, during an 11 year period. They found that overall 84.5% of the patients achieved wound healing. Their data support the value of Syme ankle disarticulation in diabetic patients with infection or gangrene.

Laughlin et al. retrospectively reviewed the surgical results and functional outcome of 52 patients treated with Syme amputations for forefoot gangrene. Wound healing was correlated with the preoperative status of the posterior tibial artery and follow-up averaged 27 months. The authors found that that posterior tibial artery Doppler examination is predictive of healing in the Syme amputation performed on diabetics, and that furthermore, diabetics can attain a functional level of ambulation with a Syme amputation.

Illustration A shows a clinical photo of a standard Syme amputation with a healthy heel pad which can allow for limited weight bearing in the absence of a prosthesis.

Incorrect Answers:
1,2,4,5: All of these amputation levels have lower energy expenditure increases than a transfemoral amputation.