When is a more proximal amputation needed?

A pneumatic reconfigurable socket for transtibial amputees

Many transtibial amputees rate the fit between their residual limb and prosthetic socket as the most critical factor in satisfaction with using their prosthesis. This study aims to address the issue of prosthetic socket fit by reconfiguring the socket shape at the interface of the residual limb and socket. The proposed reconfigurable socket shifts pressure from sensitive areas and compensates for residual limb volume fluctuations, the most important factors in determining a good socket fit. Computed tomography scan images are employed to create the phantom limb of an amputee and to manufacture the reconfigurable socket. The performance of the reconfigurable socket was evaluated both experimentally and numerically using finite element modelling. The study showed that the reconfigurable socket can reduce interface pressure at targeted areas by up to 61%.

Ilizarov external frame technique for pirogoff amputations with ankle disarticulation and tibiocalcaneal fusion

BACKGROUND

The high rates of wound failure, persisting infection, and nonunion of the tibiocalcaneal arthrodesis are the main reasons why the Pirogoff ankle disarticulation is rarely used for limb salvage. Use of the Ilizarov external frame has increased our fusion rate. The purpose of this study was to review our experience with the use of the Ilizarov external frame as a technique for Pirogoff amputations with ankle disarticulation and tibiocalcaneal fusion.

METHODS

Twenty-four patients (median age, 57.4 years; range, 29-76 years) underwent a Pirogoff amputation with Ilizarov external frame use between January 2004 and June 2011. The most common indications were gangrene with uncontrollable infection due to Charcot arthropathy or chronic osteomyelitis. Four patients had sustained crush injuries of the foot. All patients were clinically and radiographically followed for a minimum of 12 months. Additionally, 15 patients were evaluated using the Taniguchi rating scale for Pirogoff amputations after a mean follow-up of 44.9 months (range, 12-86 months).

RESULTS

In 21 patients (87.5%), a well-healed Pirogoff stump was achieved after a mean external fixation time of 18.1 weeks (range, 12.7-26.6 weeks). Impaired vascular perfusion was found to be the limiting factor for successful wound healing and an overall successful Pirogoff amputation. According to the Taniguchi scale, 67% of the patients achieved good or excellent functional results. Fair (27%) and poor (6%) results were observed only in the diabetic patients.

CONCLUSION

Using the Ilizarov external frame allowed safe fixation and a high success rate, even in neuropathic feet. The frame allowed for immediate weight-bearing and soft tissue control; however, frame-associated complications were common and could result in revision surgery.

LEVEL OF EVIDENCE

Level IV, case series.

Dermal substitute template use in diabetic foot ulcers: case reports

Diabetic foot ulcers are a source of significant morbidity. Maximizing limb salvage is an important long-term objective. The use of dermal substitutes to aid limb salvage and reduce amputation rates has been described recently in the literature. Dermal substitutes were initially described in burns and have been demonstrated to be useful adjuncts in the management of these wounds. In diabetic foot ulcer management, the outcomes of the use of the dermal substitutes are limited. The authors describe their experience of the use of INTEGRA®, a collagen-glycosaminoglycan dermal substitute, in 2 patients who presented with diabetic foot ulcers with exposed tendons.

The use of a dermal substitute to preserve maximal foot length in diabetic foot wounds with tendon and bone exposure following urgent surgical debridement for acute infection

In this study, we evaluated the utility of a dermal substitute for preserving maximal foot length after urgent surgical debridement. Patients referred to our Diabetic Foot Center with foot lesions were assessed for sensory-motor neuropathy, infection and critical limb ischaemia. The presence of acute foot infection indicated the need for immediate surgical debridement. The degree of amputation, if necessary, was based on the amount of apparently non infected vital tissue. When vital tendon/bone tissue remained exposed, the lesion was covered with a dermal substitute. From January to December 2008, 393 patients underwent surgical treatment for diabetic foot syndrome; 30 patients underwent immediate surgical debridement resulting in exposed tendon and/or bone tissues. An average of 4.4 +/- 2.1 days following surgical debridement, all 30 patients underwent dermal regeneration template grafting to cover-exposed healthy tendon and bone tissues, instead of achieving primary wound closure with a proximal amputation. After 21 days, a skin graft was performed. Complete wound healing occurred in 26 patients (86.7%). In these patients, the amputation level was significantly more distal (P < 0.003) with respect to that potentially required for immediate wound closure. The average healing time was 74.1 +/- 28.9 days. Four patients underwent a more proximal amputation. No patients underwent major amputation. The use of the dermal substitute for treating exposed tendon and bone tissues allowed timely wound healing and preserved maximal foot length. Continued follow-up will allow assessment of long-term relapse and complication rates. Such treatment could constitute part of the comprehensive management of diabetic wounds.

The use of a dermal substitute (integra) to preserve maximal foot length in a diabetic foot wound with bone and tendon exposure following urgent surgical debridement for an acute infection

In this report, the authors present the case of a 62-year-old female patient who was admitted to our hospital with an acute deep foot infection. The patient was taken immediately to the operating room where she underwent surgical debridement to completely remove all infected tissues; at the end of this first surgical step, all 5 metatarsal bones remained exposed dorsally. Once eradication of infection was completed, we had to decide whether to perform a transmetatarsal amputation at proximal levels, which would have allowed healing by first intention but would have left the patient with a smaller foot stump, or amputation at more distal levels followed by coverage of healthy tendon and bone tissues with a dermal regeneration template (Integra, Integra Life Sciences Corporation, Plainsboro, NJ), which would have preserved the foot stump length and allowed better walking. We opted for the second choice, and the use of a dermal template actually enabled our patient to maintain a considerable foot stump length, much longer than would have resulted from an amputation with immediate primary closure.

A novel technique for transtibial amputation in chronic occlusive arterial disease: Modified Burgess procedure

The aim of this study was to compare results of transtibial amputations performed using the Burgess or Modified Burgess techniques with those performed using the Bruckner technique. Transtibial amputation (TTA) was performed in 117 patients with Fontaine phase IV chronic arterial occlusion. Fifty-six patients with a mean age of 51.4 years were amputated by the Burgess technique between March 2000 and January 2003; and 61 patients with a mean age of 47.8 years were amputated by Modified Burgess technique between February 2003 and March 2006. In the Burgess technique, all muscles in the amputation region were preserved and the stump was closed by a long posterior flap; whereas the entire tibialis anterior muscle and part of the soleus muscle distal to the amputation level were removed in the modified Burgess procedure. Stump revision was performed in nine cases (17.3%) amputated by the Burgess technique due to necrosis at the incision site and drainage caused by the peroneal and tibialis anterior muscles; however, two cases (3.6%) of the modified Burgess procedure required stump revision. The prosthesis caused skin maceration at the lateral side of the stump in five cases (9.6%) operated with the Burgess technique and in eight cases (14.5%) operated with the modified Burgess procedure. After the rehabilitation period, 43 patients (82.6%) in the Burgess group were mobilized without crutches in an average of 162.5 days; on the other hand 51 patients (% 92.7) in the modified Burgess group were similarly mobilized in an average of 101.5 days. Our retrospective study showed that the modified Burgess technique, with its advantages and disadvantages forms an alternative to the Burgess and Bruckner techniques regarding TTAs.

[Stump retention and extension on the lower extremity]

Despite new techniques and better health programs in western industrialized nations, the numbers of amputations on the lower extremity remain constant. Approximately 100,000 amputations are performed annually in the U.S. and about 10,000 in Germany, more than 90% for gangrene resulting from ischemia and/or infection. Micro- and macroangiopathic changes in diabetes are the major cause of ischemia in the leg. The preservation of limb length and construction of an end bearing stump are important criteria for the functional outcome after amputation. Especially in trauma and tumor patients with "planned" amputations, all effort should be made to achieve an end bearing stump with sufficient length respectively an amputation level that is suitable for orthosis instead of prosthetic supplementation. After amputation, an interdisciplinary approach is mandatory to achieve sufficient soft tissue coverage or stump distalization. In case of insufficient bearing ability of the stump, various reconstructive possibilities must be considered to assure optimal outcome.

CONCEPTS OF TRANSTIBIAL AMPUTATION: BURGESS TECHNIQUE VERSUS MODIFIED BRÜCKNER PROCEDURE

The technique of a long posterior myocutaneous flap described by Ernest M. Burgess in the late 1960s is one of the most frequent procedures for below-knee amputations worldwide. To account for some potential problems associated with this procedure in patients with occlusive arterial disease, Lutz Brückner developed a modified amputation technique for transtibial amputation in the 1980s. Although this new standardized procedure has been widely used in Germany, it is not well known outside central Europe, secondary to its lack of description in English published work. In this review article, we describe a comparison of the technical aspects of the Burgess procedure with the modified Brückner technique for transtibial amputations. In addition, the charts of 69 consecutive patients with end-stage occlusive arterial disease undergoing below-knee amputation by either of the two standardized procedures (Burgess, n = 29; Brückner, n = 40) were reviewed. The clinical results of the two procedures are reported and compared. Review of the German published work suggests that the two techniques for transtibial amputation in patients with occlusive arterial disease appear to have similar results. This is further supported by data from our own 10-year experience with 69 patients undergoing below-knee amputation by either of the two standardized procedures. This suggests that the Brückner technique is at least equivalent to the Burgess procedure with regard to the clinical outcome in patients with occlusive arterial disease. The potential advantages of the standardized modified Brückner procedure compared with the 'classical' Burgess technique for transtibial amputation remain to be assessed in prospective multicentre trials.

Predictive value of 99mTc-sestamibi scintigraphy for healing of extremity amputation

PURPOSE

Although various non-invasive procedures have been proposed to determine the optimal level of amputation of limbs in patients who have vascular disease, currently there are no consistent criteria that can be applied before surgery. The purpose of this study was to determine whether (99m)Tc-sestamibi imaging can accurately predict the healing of amputation sites.

METHODS

In a prospective study in 26 patients (21 men, 5 women; age range 23-94 years) presenting with ulcers or gangrene of the foot and hand, (99m)Tc-sestamibi imaging was performed preoperatively. The indications for amputation included gangrene (23 patients), electrical injury (2 patients) and trauma (1 patient) of extremities. Although the amputation levels were chosen according to clinical criteria and scintigraphic results, the final amputation level was defined by scintigraphic results. Two below-knee, one above-knee, 12 toe, 11 transmetatarsal, two phalanx, one finger and one thumb amputations and one shoulder disarticulation were performed. In four cases, the amputation defect was not suitable for coverage using a local dermal flap; rather, it was covered with free tissue transfer. Patients had clinical follow-up for 6-36 months (mean 11.69 months) to assess healing of the stump. Scan results were compared with clinical outcome to assess prediction of healing.

RESULTS

There was healing in all amputations at the end of the follow-up period. When evaluated regarding preoperative (99m)Tc-sestamibi uptake pattern, there was no perfusion to the lesion site in 21 patients and perfusion to an area smaller than the extent of skin necrosis in four patients; thus, in these 25 patients, (99m)Tc-sestamibi scintigraphy suggested non-viable tissue in the extremities with clear-cut edges of perfused muscle tissue. Diffusely decreased uptake was seen below the left knee in one case. How scintigraphy changed management was analysed. The amputation levels proposed before scintigraphy were divided into two groups, "definite" (n=14) and "indefinite" (n=12), based on visual examination and Doppler findings. In nine patients in the definite group, the proposed amputation level before scintigraphy was not altered by the scintigraphic data. However, (99m)Tc-sestamibi scan enabled unnecessarily high amputation levels to be avoided in 12 patients in the indefinite group and in five patients in the definite group. Therefore, there was change in management of 65% of cases based on scintigraphic findings.

CONCLUSION

Since healing of the stump was seen in all cases, outcome was correctly predicted by scintigraphy. This preliminary study supports the use of (99m)Tc-sestamibi scan in selecting the optimal amputation level consistent with subsequent stump healing.