Evolving techniques in foot and ankle amputation

Rehabilitation of patients after diabetic foot amputation

Background: Diabetic foot is a diabetes-related complication that often requires amputation due to ulcer, necrosis, infection, and wound healing problems. Amputation decreases ambulation ability and worsens the patient’s general condition. Thus, active gait training is important after amputation.Current Concepts: The level of amputation depends on the anatomical position, for example, toe amputation and transfemoral amputation. The impairment of ambulatory function is also determined by the position of amputation. Continuous rehabilitation exercise is encouraged for ambulation before surgery. Wound management and pain control are needed for early rehabilitation exercise after surgery. The maturation of the amputation stump is especially important and needed for prosthesis wearing. If the general condition of the patient permits, muscle strengthening exercises, joint range of motion exercises, and ambulation exercises should be started as soon as possible.Discussion and Conclusion: Sufficient understanding of functional decline after amputation is required. The clear goal of ambulation should be set in consideration of the patient’s general condition and ability to walk before surgery. The ultimate goal of amputation is not only to remove necrosis, ulcers, and infected tissues but also to restore ambulatory function. Thus, expertise and significant effort before and after surgery are required.

Evaluating Blood Loss and the Effect of Antiplatelet Treatment in Foot and Ankle Amputations

The interrelationship between diabetes mellitus and cardiovascular disease is well-documented, and, secondary to the latter, is the use of antiplatelet therapy. Although diabetes and the associated vascular manifestations are driving forces behind lower extremity amputations, few data are available on the risks of perioperative antiplatelet therapy with foot and ankle amputations. The goal of the present study was to address the surgical effect of continuing or discontinuing antiplatelet therapy before foot and/or ankle amputation. The following data were retrospectively collected: blood loss, pre- and postoperative hematocrit and hemoglobin, operative time, amputation type, age, diabetic status, antiplatelet treatment, and number of transfusions during the perioperative period. Perioperative antiplatelet therapy was defined as exposure to aspirin or clopidogrel within 3 days before surgery. To compare the outcomes between groups, the following factors were analyzed using bivariate analyses and then multivariate regression models: (1) the need for transfusions, (2) high blood loss (>20 mL), (3) volume of blood loss, and (4) operative time. The noninferiority of continued antiplatelet use was assessed in terms of operative time and blood loss, using a noninferiority margin of 10 minutes or 10 mL, respectively. Antiplatelet therapy was not a statistically significant risk factor for any of the studied outcomes on multivariate analysis. Equivalence testing revealed that continuing antiplatelet therapy is not inferior to discontinuing perioperative therapy in terms of blood loss and operative time. Multivariate analysis of the data suggested that antiplatelet therapy has no statistically significant impact on blood loss, transfusion rate, or operative time.

Revision Rate and Risk Factors After Lower Extremity Amputation in Diabetic or Dysvascular Patients

This article reports the revision rate and possible risk factors for lower extremity amputations in patients with diabetes mellitus or peripheral arterial disease (PAD). Data were collected from 421 patients with diabetes mellitus or PAD who underwent amputations of the lower extremity at the authors' institution from 2002 to 2012. There was a 25.2% overall revision rate. Mean time from amputation to revision was 244 days (range, 2-2590 days). Patients with diabetes mellitus had a significantly higher rate of revision to a more proximal level compared with patients without diabetes mellitus (type 1: odds ratio [OR]=3.73; 95% confidence interval [CI], 1.21-11.52; P=.022; and type 2: OR=2.3; 95% CI, 1.07-4.95; P=.033). A significant increase in revision rates was observed from Fontaine stage 0 to IV (stage 0: 17.9%; stage IV, 34.7%; P=.03). Risk factors for revision were diabetic nephropathy (OR=2.26; 95% CI, 1.4-3.63; P=.001) and polyneuropathy (OR=1.68; 95% CI, 1.03-2.73; P=.037). Patients who underwent revision amputation had a significantly younger mean age than patients who did not undergo revision amputation (65.23 years [range, 40-92 years] vs 68.52 years [range, 32-96 years]; P=.013). Anticipated amputation in this patient population requires a multidisciplinary approach with optimization of the patient's health. In the authors' clinical practice, the determination of the appropriate amputation level is performed individually for each patient, considering the risk factors identified in this study and the patient's expected mobilization potential, social background, and acceptance of a more proximal primary amputation level.

Primary closure of elective toe amputations in the diabetic foot--is it safe?

BACKGROUND

Toe amputation is the most common partial foot amputation. Controversy exists regarding whether to primarily close toe amputations or to leave them open for secondary healing. The purpose of this study was to evaluate the results of closed toe amputations in diabetic patients, with respect to wound healing, complications, and the need for further higher level amputation.

METHODS

We retrospectively reviewed the results of 40 elective or semi-elective toe amputations with primary closure performed in 35 patients treated in a specialized diabetic foot unit. Patients with abscesses or necrotizing fasciitis were treated emergently and were excluded. Patients in whom clean margins could not be achieved due to extensive cellulitis or tenosynovitis and patients requiring vascular intervention were excluded as well. Outcome endpoints included wound healing at 3 weeks, delayed wound healing, or subsequent higher level amputation.

RESULTS

Out of 40 amputations, 38 healed well. Thirty amputations healed by the time of stitch removal at 3 weeks and eight had delayed healing. In two patients the wounds did not heal and subsequent higher level amputation was eventually required.

CONCLUSIONS

In carefully selected diabetic foot patients, primary closure of toe amputations is a safe surgical option. We do not recommend primary closure when infection control is not achieved or in patients requiring vascular reconstruction. Careful patient selection, skillful assessment of debridement margins and meticulous technique are required and may be offered by experienced designated surgeons in a specialized diabetic foot unit.

The utilization of a suture bridge construct for tibiofibular instability during transtibial amputation without distal bridge synostosis creation

Symptomatic distal tibiofibular instability is a known complication of trauma-related transtibial amputations. Overt proximal tibiofibular dislocations, which are easily recognized on routine radiographs, may occur concurrently with the traumatic injury or amputation. More commonly, however, the proximal tibiofibular joint remains structurally intact in the presence of distal instability due to the loss of the distal syndesmotic structures and damage to the interosseous membrane, resulting in fibular angulation and distal tibiofibular diastasis. Some authors have espoused treating this instability with the creation of a distal tibiofibular bridge synostosis (the so-called Ertl procedure or modifications there of) to prevent potentially painful discordant motion and to minimize the prominence of the residual distal fibula. Recent studies, however, have suggested an increase in complication and reoperation rates in transtibial amputations that received a bridge synostosis compared with standard transtibial amputations. Additionally, although there are several described techniques for bridge synostosis creation, most are dependent on having sufficient remaining fibula to construct the bone bridge without unnecessary shortening of the tibia; however, sufficient residual fibula is not always available after traumatic and trauma-related amputations. We propose a technique utilizing a suture bridge to restore tibiofibular stability when performing transtibial amputations in patients with proximal tibiofibular dislocations or distal diastasis, avoiding the potential need for a distal bridge synostosis.