Use of tissue expansion in revision of unhealed below-knee amputation stumps.

When local tissue is insufficient for the revision of unhealed below-knee stumps tissue expansion offers an interesting alternative for local coverage. We used this method in seven patients (five men, two women; mean age 30 years) who had had below-knee amputations, six of them after injury to a healthy limb and one for purpura fulminans. Ten tissue expanders were inflated slowly and intermittently either weekly or twice weekly depending on the patients. The mean expansion period was 92 days. Mean hospital stay for the two operations was 5.8 (range 4-9) and 7.6 (range 6-10) days, respectively. Using subjective and objective criteria, functional outcome was excellent in five patients and good in one. Expansion failed in one because of infection. Expanded skin flaps allow good cover with a minimal scar area in appropriate cases, while preserving the skin sensitivity and length of the tibial shaft.     

Wedge resection of amputation stumps. A valuable salvage procedure

We describe the technique of wedge resection for revision of an amputation stump, and report the results of this at below-knee level in 57 patients with peripheral vascular disease; healing occurred in 42 of these (74%).     

Free fillet foot flap for salvage of below-knee amputation stump

Management of extensive bone and soft tissue defects, which occur after severe trauma of lower extremities and always lead to anunacceptable amputation in some cases, continues to challenge reconstructive surgeons. When performing lower extremity amputation, preservation of the knee joint has been put into a higher priority. The benefit of below-knee amputation over above-knee ones concentrates on a more normal gait with less energy expenditure during ambulation when a functioning knee joint is present.     

Primary closure of below-knee amputation stumps: A prospective study of sixty-two cases

Between January 1, 1985, and December 31, 1988, we prospectively studied the outcome of 62 consecutive below-knee amputations with primary closure in 56 patients. There were 35 men and 21 women; mean age was 70 years. Above-knee amputation was performed for occlusion of the profunda femoris artery, acute thrombosis of a popliteal aneurysm with inadequate sural artery vascularity, intractable knee flexion contracture, suspended ischemia, and occasionally, when ischemia was found intraoperatively to extend proximally during below-knee amputation. Bedridden patients deemed unfit for prosthetic devices were also candidates for above-knee amputation. Fifty-four lower extremities (87%) were gangrenous and rest pain was present in eight patients (13%). Twenty-nine limbs (47%) were amputated primarily, 33 (53%) after failure of one or more revascularization procedures. Six patients had bilateral amputation. Forty patients (71%) were diabetic. Mean hospital stay was five days. Fifteen patients (27%) died during a mean follow-up period of 29 months. Eleven stumps (17.5%) required reoperation: five for postoperative infection, four for wound breakdown after a fall, and two for secondary abscess. Three secondary above-knee amputations (5%) were necessary. Of 44 below-knee amputations in diabetic patients, one had to be revised at the level of the thigh. Of 33 amputations after revascularization failure, one secondary above-knee amputation was necessary. Restoration of preischemic status was achieved after a mean of 58 days. Upon patient discharge from a rehabilitation center, 44 stumps (81%) were suitable to be fitted with prostheses. Compared with the open-stump technique, primary closure of below-knee amputation stumps reduces healing time without an increased reoperation rate. Hospitalization is short and reestablishment of patient autonomy is rapid.Presented at the Annual Meeting of the Société de Chirurgie Vasculaire de Langue Française, Strasbourg, France, June 23–27, 1989.     

A Swedish knee-cage for stabilizing short below-knee stumps.

Stump length is an important factor in attaining successful prosthetic rehabilitation in below-knee (BK) amputees. Stability of the stump-prosthesis complex is impaired in the case of a stump shorter than 10 cm. Thus, fitting a prosthesis to a BK amputee with a stump which is very short often requires the use of different prosthetic techniques. In this work, the authors suggest the use of a Swedish knee-cage attached to a conventional patellar-tendon-bearing prosthesis as an alternative solution in the case of a short BK stump. Objective evaluation was performed by an analysis of gait and the foot-ground reaction forces. The results obtained indicate an improvement in all the measured parameters resulting from the modified stump-prosthesis complex.     

Management of infection of major amputation stumps after failed femorodistal grafts

A retrospective review was performed of 174 patients who underwent 199 lower-extremity amputations for unreconstructable vascular insufficiency from 1976 to 1983 at the Northwestern University Medical Center. This study was initiated to identify the cause of amputation wound healing complications and secondary ascending prosthetic graft infection, as well as to propose a plan of management for the failed prosthetic grafts at the time of major limb amputation. Ninety-eight amputations were performed primarily, 12 were performed secondary to graft infection, and 89 were performed in patients who had previously undergone infrainguinal arterial bypass procedures. At the time of amputation, graft management consisted of high transection and suture ligation, allowing the graft to retract into the substance of the stump and away from the skin suture line and weight-bearing area of the limb. Delayed stump healing was noted to occur more commonly in the group who had undergone previous bypasses as opposed to those who had undergone primary amputation (34.8% versus 14.3%). Fourteen graft infections developed in 89 patients after amputation (15.7%), which is significantly higher than the overall 1.4% incidence of lower-extremity bypass infections that occurred during the same interval in patients with intact extremities. In addition, it was found that when infected grafts in amputated limbs were completely removed, stump healing without recurrent wound and graft sepsis was better than when treated locally or with partial graft removal. We therefore recommend removal of a thrombosed graft with an infected wound or an infected graft at the time of major limb amputation to decrease the incidence of wound complications and graft infection.     

A plaster-pylon technique for below-knee amputation

We reviewed 83 patients after below-knee amputation. In 56 with 69 amputations early management was by plaster-pylon. A plaster cast is applied in the operating room, and a pylon added one week later, after which full weight-bearing is allowed. We compared these patients with 27 who had soft bandaging. The 'healing' time was reduced from 98 days to 40 days, and there were no major complications in the plaster-pylon group. The technique is simple and cheap and can be used by paramedical staff without specialised training or equipment.     

Temporary prosthetic fitting for below-knee amputation

The problems encountered in fitting and using the permanent below-knee prosthesis in developing countries are the high price of the prosthesis, inadequate fitting and lack of proper rehabilitation. In Turkey, the preferred treatment of the stump post-operatively is by the soft dressing method with bandaging for maturation and shrinkage. Generally, the application of the permanent prosthesis is in the sixth month post-operatively. Since in patellar-tendon-bearing (PTB) sockets, stumps have to withstand high pressures in limited areas, the PTB socket can only tolerate small volume changes in the stump. For this reason bandaging over a long period may be insufficient for adequate stump shrinkage and amputees will need another below-knee prosthesis, which most of them cannot afford after only a few weeks use. In the authors' clinic, 19 amputees were fitted with simple, effective and inexpensive temporary prostheses following either conventional immediate post-operative dressing or the soft dressing method. The temporary prosthesis is worn for two months. It produces fast stump shrinkage, helps maturation and permits ambulatory discharge even in bilateral amputees. For economical reasons, only eight of nineteen patients were fitted with permanent prostheses, all wearing them successfully without the necessity of further rehabilitation.     

Can the failure of a below-knee amputation be predicted? Predictability of below-knee amputation healing

The predictability of below-knee amputation healing was evaluated in 69 patients with severe distal ischaemia with or without diabetes mellitus. A special attempt was made to find out predictors of amputation failure. Of 71 amputations performed 20 failed. Preoperative systolic blood pressures and skin perfusion pressures were significantly higher at the level of amputation in patients whose amputations healed than in those whose amputations failed, mean 69.5 (SD 33.4) mmHg and 55.9 (SD 27.0) mmHg vs. 41.5 (SD 31.6) mmHg (p less than 0.01) and 35.6 (SD 13.9) mmHg (p less than 0.05), respectively. There was, however, considerable overlapping and only if calf systolic blood pressure was unmeasurable did below-knee amputations always fail. PVR and skin perfusion pressure data were useful in disclosing falsely high calf systolic blood pressures apparently caused by mediasclerosis. When these patients with pseudohypertension were excluded the presence of diabetes did not affect the pressure readings. The blood viscosity as indicated in this study by pre- and postoperative haemoglobin levels did not affect amputation healing. The present results suggest that vascular laboratory data are useful as supplementary information in the assessment of below-knee amputation healing but it can predict amputation failure only when no Doppler signals are present at the ankle level.     

Revision of amputation stumps in Dodoma--Tanzania.

The records of Dodoma Orthopaedic Department, Tanzania were reviewed for the period July 1986 to December 1990 in order to identify the reasons for revision surgery. A total of 26 patients required revision surgery. Two main groups were identified. In the first group 4 patients had a higher level of amputation because of gangrene. In the second group 22 patients had revision surgery because of other stump defects caused by technical mistakes when carrying out the original amputation, or other complications.     

The role of microvascular free flaps in salvaging below-knee amputation stumps: a review of 22 cases

Twenty-two cases of traumatic below-knee amputation stumps with inadequate soft-tissue coverage salvaged with microvascular free flaps were reviewed retrospectively. All patients would have required an above-knee amputation for prosthesis fitting had microvascular free flaps not bee utilized. A total of 24 flaps were used in 22 patients; parascapular 11 (46%), foot filet six (25%), latissimus dorsi four (17%), lateral thigh, tensor fascia lata, and groin one (4%). Free flaps were performed immediately after injury in five (21%) cases, within the first week in two (8%), between 1 and 3 months in 12 (50%), and after 3 months in five (21%). Fifty per cent of the patients had significant other injuries. The patients had a total of 107 operations (mean, 4.9) related to their injury: 33 (mean, 1.5) of those operations were after the free flap, 27 (25%) of which were either performed because of a complication of the free flap or for revision of the free flap. Complications included partial necrosis in five (21%), neuroma in three (13%), hematoma in two (8%), donor site complication in two (8%), thrombosis requiring reoperation in one (4%), and flap failure in one (4%). Patient followup ranged from 12 to 116 months. All patients maintained a functional below-knee prosthetic level. The mean time to ambulation was 5.75 months, and was not significantly affected by flap complications. Most patients employed before their injury were employed after their injury. Despite a protracted course in these severe injured trauma patients, a functional below-knee amputation level was preserved in all cases utilizing microvascular free flaps.     

Muscle transposition and skin grafting for salvage of below-knee amputation level after bilateral lower extremity thermal injury

Thermal injury to the lower extremity sometimes necessitates amputation around the knee joint. Knee function is so critical to prosthetic rehabilitation that every attempt should be made to salvage the knee joint. This report presents an unusual case of bilateral lower extremity flame burn requiring amputations. While the distal two-thirds of the legs and both feet were totally necrotic, the thermal damage was limited to skin and subcutaneous tissue sparing muscle and bone in the proximal one-third of the legs and posterior thighs. The below-knee amputation level was salvaged by muscle transposition over the anterior tibia and resurfacing of muscle cuffs with thick split-thickness skin grafts. The post-operative period was uneventful. Amputation stumps tolerated the below-knee prosthesis well and the patient attained independent functional prosthetic ambulation at the post-operative fourth month. It is known from the reconstruction of the plantar foot that skin-grafted muscle tissue tolerates weight bearing and shearing forces well. This principle can also be used for salvage aspects of the below-knee amputation level.     

Turn-up bone flap for lengthening the below-knee amputation stump

When amputation just below the knee becomes necessary after extensive loss of bone from the tibia and of anterior soft tissue in the treatment of tumours, fractures or infection, the remaining proximal tibia may be too short for a below-knee prosthesis, although the knee may be normal. We have included the distal tibia or foot in a long posterior flap by turning it up thus increasing the length of a very short proximal tibial stump. The knee is thereby saved, allowing satisfactory use of a below-knee prosthesis. This technique is particularly applicable when the distal leg is normal and well vascularised. Five procedures have been undertaken. We present two illustrative cases.