Why Partial First Ray Amputations In Patients With Diabetic Neuropathy Do Not Work
The initial level of amputation is detailed in the chart at right. Healing of the surgical incision occurred in all 59 patients.5 However, 69 percent (41 patients) went on to develop a foot ulceration following the index amputation in a mean of only 10.5 months with an average of 3.1 ulcerations per patient. Additionally, 36 percent (21 patients) required ancillary surgical procedures. There was a mean of 26.6 clinical visits per patient from the time of initial amputation to when either complete healing had occurred with no further ulcerations or definitive re-amputation occurred. In addition, 92 percent of patients took prescription antibiotics postoperatively with a mean of 2.3 different antibiotics prescribed. Unfortunately, 25 (42.4 percent) patients had a more proximal re-amputation within a short mean of 25 months. Interestingly, the most common level of re-amputation did not occur more proximally within the first ray.
Our data determined that in a community-based hospital setting, half of the patients with diabetes and peripheral sensory neuropathy undergoing any version of a partial first ray amputation will eventually require more proximal re-amputation.5 This data questions the reliability and durability of this level of amputation as a primary procedure in this patient population. Additionally, it does not seem fiscally sound.
The goal of any amputation is the complete eradication of non-viable tissue, optimizing the host’s healing potential while reducing the risk for further breakdown and the need for extended local wound care, specialized shoe gear or repeated surgical intervention.4 As we demonstrated in the aforementioned studies, a partial first ray amputation at any level in patients with diabetic neuropathy does not meet these goals in this high-risk population in which risk management is especially critical.4 Even a partial hallux amputation had the same potential for re-amputation as a near complete first ray amputation. This implies the significant role the first ray has in the function of the foot and limited tolerance for amputation at this level in insensate feet.
As we noted in the second study, nearly half of these patients will require a more proximal level of re-amputation within a mean of 25 months. There was also a high mortality rate within this patient population with 48 percent of the patients deceased at a mean time of 34.6 months following the index amputation. While one may attribute this to the disease process itself, the mean age of included patients was only 67 years old. Due diligence is therefore required when evaluating the patient to determine the optimal level of initial amputation and may require a more proximal level.3-13
Further, after review of our studies, it may be in the patient’s best interest to get a referral to a more specialized diabetic foot center of excellence since the incidence of re-amputation is half of what results when the patient receives care in a community-based facility. The exact reason for this remains a matter for conjecture since the same multidisciplinary team members (i.e., internal medicine/endocrinologists, infectious disease, vascular surgery, nutritionists, etc.) are present in both settings studied. Further study to elucidate this apparent discrepancy (including non-hospital based private practitioner outcomes) is warranted.