Increased limb salvage by the use of unconventional foot amputations

Increased limb salvage by the use of unconventional foot amputations Benjamin B. Chang, MD, Devon E. M. Bock, MD, Richard L. Jacobs, MD, R. Clement Darling III, MD, Robert P. Leather, MD, and Dhiraj M. Shah, MD, Albany, N. Y. Purpose: Limb salvage in the presence of ischemic foot necrosis requires revascularization followed by debridement or partial foot amputation. Necrosis extending beyond the toes and metatarsal heads may require the use of unconventional types of amputations. Methods: Over a 15-year period 2105 ischemic limbs were treated with infrainguinal revascularization. In 98 cases, extensive foot necrosis was then managed with amputations, including 59 modified Chopart, 14 Lisfranc, 17 Pirogoff and 8 Syme amputations. Patients were not allowed to bear weight for several days to weeks. Results: Skin flap necrosis in 14 cases was managed successfully by debridement and skin grafting. Ambulation required the use of a "clamshell" prosthesis and foot spacer. The overall limb salvage rate in this group was 84% (82 of 98). In general, the modified Chopart amputation most frequently produced ambulatory limb salvage and is technically easier to perform than a Syme amputation. Patient satisfaction and long-term ambulatory function was highest with the modified Chop art. Conclusions: Ischemic foot necrosis extending beyond the limits of conventional transmetatarsal amputation need not be treated with major amputation. This requires the surgeon to be well versed in the use of less common types of partial foot amputations. Acceptable limb salvage and good functional results may be attained by the motivated patient and surgeon with the use of these procedures in the revascularized limb. (J VAse SURG 1994;19:341-9.)

The treatment of patients diagnosed with partial foot gangrene and ischemia is often a complex challenge. Clearly, advances in distal revascularization have allowed vascular surgeons to reliably improve perfusion in the large majority of cases. 1-5 However, ultimate salvage of a functional limb also involves eradication of infection, removal of necrotic tissue, fashioning a functional amputation and rehabilitation. Although treatment of digital or distal forefoot necrosis with toe, ray, or transmetatarsal amputations is well accepted by the surgical community, more extensive forefoot and heel necrosis is often regarded as a sign that the limb is likely to be unsalvageable and therefore best treated with an expeditious major amputation. The use of more extensive forefoot amputations in these cases, such as a Lisfranc or From the Albany Medical College and V.A. Hospital (Dr. Bock), Albany. Presented at the Forty-first Scientific Meeting of the International Sociery for Cardiovascular Surgery, Washington, D.C., June 7-8,1993. Reprint requests: Benjamin B. Chang, MD, Albany Medical College, Vascular Surgery, A-61 VA, 47 New Scotland Ave., Albany, NY 12208. 24/6/52343

Chopart amputation is not commonly regarded as a viable or effective means of achieving limb salvage. 6 ,7 Herein is presented the authors' experience with unusual partial foot amputations in these patients with ischemic, necrotic distal extremities after revascularization. CLINICAL METHODS Patients with ischemic necrotic limbs were treated jointly between the vascular surgery service and an orthopedic surgeon (R.L.J.). Limbs believed to be clearly unsalvageable were amputated at the above- or below-knee level. All other limbs were treated with immediate administration of intravenous antibiotics. Need for revascularization was determined by physical examination, segmental pressures, and pulse volume recordings. Biplanar arteriography of the involved limb including the ankle and foot was performed. Revascularization was performed expeditiously, usually within 48 hours, with no attempt to "control" all infections before revascularization. In general, an effort was made to revascularize the foot as directly as possible. Thus patients with extensive foot necrosis and multilevel disease underwent complete revascularization before attempted 341

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A B Fig. 1. A, Lisfranc amputation performed at tarsometatarsal joint (1). Chopart amputation performed at talonavicular-calcaneocuboid joint (2) . B, Completed Lisfranc amputation.

amputation. In addition, the distal anastomosis was placed distal to any or all occlusive lesions whenever possible. Therefore distal tibial or pedal bypasses were preferred over bypassing to isolated popliteal or other arterial segments. Improvement in foot perfusion was confirmed by Doppler examination and pulse volume recordings. Stable patients were sometimes allowed to demarcate for up to several days before amputation. Cellulitis was treated before amputation. Amputations involving more than a toe or ray were performed after the revascularization as a separate procedure. All partial foot amputations were performed by one surgeon (R.L.J.). At the time of surgery, these general principles were followed. The skin was transected around the necrotic area just proximal to the line of demarcation. Skin flaps were developed at this time. Underlying soft tissue was also sharply divided. The skin and soft tissue were elevated from the bone. After an estimation of the amount of viable skin was made, the bones were transected at the appropriate level. For extensive forefoot necrosis, the foot was disarticulated at Lisfranc's joint or Chopart's (calcaneocuboid) joint (Fig. 1).8 More extensive necrosis was treated with a modified Pirogoff or Syme amputation (Fig. 2) .8,9 For these latter types of amputation, heavy pins were used to secure the rotated calcaneus or heel pad to the tibial plafond. These pins were removed in 8 to 12 weeks after

bridging callus was seen on radiographic examInation. All protruding tendons were excised. Exposed joints were excised back to bleeding cancellous bone. All avascular collagenous tissue in the flaps was also excised. Flaps were then fashioned to cover the amputation. These flaps were often based on a medial or lateral pedicle and were often not symmetric. A 10F Jackson-Pratt drain was usually placed through a separate stab incision. Soft tissue was reapproximated with interrupted 2-0 Dexon sutures (Davis & Geck Div., American Cyanamid Co., Wayne, N.J.). The flaps were approximated with interrupted 4-0 nylon sutures. Small bites were taken to minimize flap ischemia. A tension-free closure was mandatory. A bulky dressing without elastic compression was applied. Of particular importance, the Chopart amputation was modified by severing the heel cord at the end of the case with a no. 11 knife blade inserted behind the heel (Fig. 3). This maneuver allows the foot to remain in a neutral position and avoids the problem of eventual foot deformity (equinus) produced by the unopposed pull of the gastrocnemius. Partial flap necrosis was managed by excision and skin grafting whenever appropriate. Patients were discharged from the hospital when intravenous antibiotics were no longer needed and the wounds appeared to be adequately healing. Outpatient care

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c A

8

A

B Fig. 2. A, Pirogoff amputation with talus removed and calcaneus rotated. Opposing tibial plafond and calcaneus are trimmed to bleeding cancellous bone. Aligning pins remain in position until callus has formed. B, Syme amputation with both talus and calcaneus removed. Fat pad is preserved beneath tibial plafond.

Fig. 2. C, Completed Pirogoff amputation.

was given by the vascular and orthopedic surgeons. Further debridement of open wounds was performed as required. Full weight bearing was not permitted until full healing was obtained, usually at least 6 to 8 weeks. After healing, Chopart, Pirogoff, and Syme amputations were fitted with a polypropylene "clamshell" prosthesis (Fig. 4). This type of prosthesis allows the patient to ambulate with a regular oxford-type shoe and minimizes the "pumping" action seen with these proximal amputations that often lead to blistering or ulceration. MATERIALS Over a IS-year period, 2105 ischemia limbs were revascularized with infrainguinal reconstructions. Of

these, 98 (4.7%) were treated with a Lisfranc, Chopart, Pirogoff, or Syme amputation. The average age was 68 years (range 42 to 91 years); 57% of patients were men, and 43% were women. Diabetes was present in 82.7% (81 of98) and 83.7% (82/98) had a history of smoking. The initial presentation of these patients was acute ischemia in 10.2% (10) and chronic ischemia in 89.8% (88). The chronic ischemia group included gangrene (n = 55), nonhealing ulcer (n = 12), and nonhealing amputation site (n = 21). The revascularization performed and the site of distal anastomosis are listed in Tables I and II, respectively. In addition, 19 (10.4%) of these limbs had previous vascular reconstructions performed or

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344 Chang et at.

A

Fig. 3. A, Percutaneous heel cord lengthening is performed with Chopart amputation to maintain neutral position of foot, avoiding ulceration from equinous deformity. B, Completed Chopart amputation.

A

c i -~

Fig. 4. A, Prolypropylene "clamshell" prosthesis used with Chopart, Pirogoff and Syme amputations. Prosthesis is composed of anterior and posterior shell (a, b) and foam insert in toe box (c). B, Seen here with street shoe, this minimizes blistering from pumping action.

attempted. Twelve (12.3%) underwent previous contralateral above- or below-knee amputations. Four patients in this series had bilateral partial foot amputations performed.

Follow-up of revascularizations and amputations was performed jointly by the authors. Assessment of bypass patency was performed by segmental Doppler pressures, pulse volume recordings, and, later in the

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Table I. Revascularizations performed

Table II. Distal anastomosis 56

In situ bypass Excised vein Femoral popliteal endarterectomy Polytetrafiuoroethylene Inflow bypass and in situ bypass Thromboembolectomy Balloon angioplasty

345

Above-knee popliteal Below-knee popliteal Anterior tibial Posterior tibial Peroneal Tibioperoneal Dorsalis Pedis

20 5 6 7 3 1

14 13 18 17 21 2

13

Table III. Amputations performed No.

Lisfranc Chopart Pirogoff Syme

14 59 17 8

Skin graft

Early failure

Late failure

2 7 3 2

7 5 1

3

(14.2%) (60.2%) (17.3%) (8.3%)

series, duplex examination. Stumps were inspected for ulceration or breakdown. Data collection was performed by a combination of chart review, physical examination, and patient and physician interview. Ambulatory status was verified by direct patient interview whenever possible.

RESULTS In this group of 98 limbs, the amputations performed are listed in Table III. Overall functional limb salvage was obtained in 82 of98 limbs (84%). Cumulative life-table analysis showed a 70% limb salvage rate at 5 years, which remained constant to 10 years. Patients were monitored an average of 35 months (range 1 to 144 months). Early failure of amputation was seen in 13 cases. In three cases, bypasses failed in the early postoperative period and were not recoverable, leading to limb loss. In the remaining 10 cases, limbs were lost in spite of patent bypasses. Of this latter group, five bypasses to isolated popliteal or tibial arteries had a poor response to revascularization caused by an inability to directly revascularize a vessel into the foot. Average ankle systolic pressure in this group was 17 mm Hg. Pulse volume recordings were class 4 or 5. In the remaining five, there was an improvement in postoperative noninvasive indexes (mean ankle systolic pressure 118 mm Hg and class 2 or 3 ankle pulse volume recordings), but the limbs were lost. Causes of limb loss in these cases were due to persistent flap or heel necrosis. Three of these patients had chronic kidney failure. In 85 (87%) limbs, there was initial limb salvage and healing of the amputation site. The mean ankle pressure in this group was 109 mm Hg (range 50 to

170 mm Hg). The mean ankle-brachial index was 0.78 (range 0.45 to 1.0). All healed amputations occurred in limbs with class 3 or better ankle pulse volume recordings. Late limb loss was seen in three cases. In two of these cases, the bypasses occluded in the late postoperative period and were not recoverable. The third patient arrived with a necrotic foot several days after late graft occlusion. Perfusion was restored with graft thrombectomy and segmental replacement, but the limb was amputated at the below-knee level because of the extent of necrosis of the foot and ankle. Eight patients required bypass revision in the late postoperative period to maintain limb viability. The revisions included four vein patches of graft stenoses, segmental bypass replacement in two and rebypass in two. Diabetes did not adversely affect healing in this group. Limb salvage was obtained in 68 of 81 patients with diabetes (84%). Limb salvage in patients with chronic kidney failure was 63 % (5 of 8). There were no significant differences in the frequency of failure between different types of amputations. In general, patients with Lisfranc or Chopart amputations were able to get out of bed at night without a prosthesis more easily than those with a Syme or Pirogoff amputation. (Fig. 5).

DISCUSSION Limb salvage is the major indication for infrainguinal vascular reconstruction. Advances in limb salvage have focused on improved methods and techniques of revascularization; bypasses to tibial and pedal arteries with patency rates comparable to more proximal bypasses are now commonplace. 1- 3,s How-

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346 Chang et at.

1 98 ____- -2:;;:: 1 ...

0 .8

70%

12

0 .6

.............................................. ....... " ................. . ... . . _....... .

0 .4

.................................................................. .

0 .2

............................................................... .

-

o~---------------------------------------------

6

12

24

36

48

60

MO

HS

72

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96

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Fig. 5. Cumulative life-table limb salvage.

ever, the other facets of patient care that lead to limb salvage also demand the attention of the vascular surgeon. Rehabilitation does not end with completion of the bypass procedure. In particular, patients diagnosed with severe ischemia and forefoot necrosis pose a vexing problem for the clinician. These patients, as in this series, most likely have diabetes. Presumably, their neuropathy and hypoesthesia or anesthesia and impaired host defenses allow for the necrosis to progress, unimpeded and undetected. Another group of patients are those treated with serial debridements and amputations either in the face of unrecognized ischemia or with inadequate revascularization. In these individuals, nonhealing is often attributed to problems in the conduct of the amputation or "impaired wound healing". Twentyone of 98 limbs in this study were transferred from other hospitals after undergoing such inadequate treatment. Many others were transferred with extensive preexisting necrosis labeled as "nonsalvageable". In the authors' experience, in agreement with other published series, there are very few limbs that should be treated by primary amputation.l ,5 Ischemic limbs with extensive forefoot necrosis may be treated with revascularization and one of the amputations described herein and elsewhere.SolO Long-term limb salvage was obtained in at least 82 limbs in this series

that might ordinarily be treated by primary major amputation. This constitutes 4.7% of the entire group of patients treated for limb salvage with infrainguinal occlusive disease. Unfortunately, these unusual forefoot amputations have been underused or regarded as historical curiosities by many.6,7 Detailed descriptions of the operative procedures may be obtained elsewhere. s A Lisfranc amputation through the tarsalmetatarsal joint provides the best functional result in that the insertions of the ankle flexors and extensors are preserved. This produces a mobile ankle held naturally in a neutral position allowing for plantigrade ambulation. A foam spacer placed in the toe box is all that is necessary for ambulation with a normal shoe. The relatively low number of Lisfranc amputations in this series reflects the extensive necrosis in this patient group. In addition, a very high trans metatarsal amputation requires relatively little additional viable skin for closure and may be preferred by some. Chopart amputations have been poorly regarded and most standard texts mention this amputation only to disparage it. 6,7,1l This is because amputation through the calcaneocuboid joint sacrifices the insertion of the foot extensors (dorsiflexors ) . The resultant unopposed pull of the gastrocnemius results

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in a steep equinus deformity of the foot, leading to ulceration and an inability to ambulate. The modification of the Chopart amputation presented herein involves the percutaneous transection of the flexor tendons (heel cord). This is critically important. The resultant foot will remain in a neutral position with a relatively large weight-bearing surface on thick, plantar skin. Ambulation over long distances requires a clamshell-type polypropylene prosthesis that is well tolerated. The patient may stand, transfer, and ambulate short distances without a prosthesis. The relatively high number of modified Chopart amputations in this series (59 of 98) reflects the usefulness of this procedure in this type of patient. The removal of the cuboid and cuneiform bones greatly reduce the amount of skin needed for tension-free closure. Furthermore, modification of the skin flaps allow for salvage of limbs without the need for skin grafts in many cases. For example, necrosis of the entire dorsum of the foot may often be treated with a Chopart closed with a long posteriorly-based flap. Necrosis of the entire first or first two rays to the midfoot may be treated with a Chopart amputation closed with a laterally-based flap. Creativity in flap design is necessary in these cases. The modified Pirogoff amputation preserves limb length and maintains weight-bearing on plantar skin. It is more deforming than lesser amputations and is technically more difficult to perform. Care must be taken not to buttonhole the skin flaps as the talus is shelled out. The resultant stump is less suitable for prolonged ambulation but is quite satisfactory for standing, transferring and ambulating short distances even without a prosthesis. The Syme amputation is technically the most difficult to perform in this group and does not fully preserve limb length. 12 However, it allows for standing, transferring, and limited ambulation without a prosthesis. The authors currently perform few of these procedures. If adequate soft tissue flaps were available, we would prefer to leave at least a portion of the calcaneus as a modified Pirogoff amputation. The importance of proper prosthetic fitting in these cases cannot be overstressed. Fitting with a clamshell-type prosthesis with a spacer minimizes the up-and-down pumping motion of these amputations in a normal shoe. The historically poor reputation of tq.ese amputations is related in part to the ulceration due to this type of movement and the difficulty of

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proper prosthetic fitting. 6 ,7,13 Patient acceptance of these amputations is very good, in spite of their limitations. The good long-term limb salvage in this series supports the addition of these types of amputations to the armamentarium of the limb-salvage surgeon. Late limb loss was due only to bypass occlusion that could not be corrected (two cases) and a delay in presentation leading to irrevocable necrosis of the entire foot (one case). There were no late amputations caused by chronic nonhealing, pain, or unsatisfactory functional result. The causes of early limb loss in this group require further mention. In five cases, postbypass noninvasive studies revealed little improvement in ABI or pulse volume recordings. Amputations in these patients uniformly failed. Therefore these types of amputations should generally be reserved for patients only after maximal direct revascularization has been obtained of the foot and ankle. Bypasses to the ankle and pedal levels are common in this group. All occlusive lesions should be bypassed. In no case did any of these amputations succeed with an ankle pressure less than 30 mm Hg or less than class 3 pulse volume recordings. Five early failures were seen in patients in spite of good restoration of perfusion. Three patients in this group had diabetes with chronic kidney failure, a notoriously difficult group in which to effect limb salvage, presumably because of poor wound healing. 12 . 14 In the remaining two, flap necrosis was abetted by persistent infection, leading to limb loss. Dietzek et al. 15 reported that the presence of diabetes, extensive pedal necrosis, advanced infection, and failure of distal hemodynamic improvement after operation were factors associated with limb loss in spite of a patent infrainguinal bypass. Overall, however, an ability to restore reasonably good perfusion to the foot and ankle was associated with high rates of limb salvage. Patients whose post revascularization pulse volume recording was class IV or V or had an ankle pressure less than 30 were not successfully treated with an unconventional foot amputation. In conclusion, the extensive foot and forefoot amputations described herein, the Lisfranc, modified Chopart, Pirogoff, and, to a lesser extent, Syme, should be remembered by vascular surgeons as a useful means of managing extensive necrosis that might otherwise label a limb as "nonsalvagable". The high rate of long-term limb salvage and acceptable functional results should make these amputations

348 Chang et at.

after revascularization much preferred to primary above- or below-knee amputations in most of these cases. REFERENCES 1. Leather RP, Shah DM, Chang BB, et al. Resurrection of the in siru saphenous vein bypass: 1000 cases later. Ann Surg 1988;208:435-42. 2. Donaldson MC, Mannick JA, Whittemore AD. Femoraldistal bypass with in siru greater saphenous vein. Ann Surg 1991;213:457-65. 3. Gupta SK, Veith FJ, Kram HB, Wengerter KR. Prospective, randomized comparison of ringed and nonringed polytetrafluoroethylene femoropopliteal bypass grafts: a preliminary report. J VAse SURG 1991;13:162-72. 4. Veith FJ, Gupta SK, Samson RH, et al. Progress in limb salvage by reconstructive arterial surgery combined with new or improved adjunctive procedures. Ann Surg 1981;194:386401. 5. Veith FJ, Gupta SK, Wengerter KR, et al. Changing arteriosclerotic disease patterns and management strategies in lowerlimb-threatening ischemia. Ann Surg 1990;212:402-14. 6. Wagner FW, Jr. Amputations of the foot and ankle. Clin Orthop 1977;122:62. 7. Lindquist C, Riska EB. Chopart, Pirogoff and Syme amputations. Acta Orthop Scand 1966;37:110-5.

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8. Jacobs RL. Diabetic neuropathic foot; Avascular Diabetic Foot. In: Jahss MH, ed. Disorders of the foot and ankle. 2nd ed. Philadelphia: WB Saunders, 1991:1926-37. 9. Nakhgevany KB, Rhoads JE. Ankle-level amputation. Surgery 1984;95:549-56. 10. Lieberman JR, Goldstock L, Durham J, Fuchs MD, Jacobs RL. Chopart amputation with percutaneous heel cord lengthening. Clin Orthop (In press). 11. Durham JR. Lower extremiry amputation levels: indications, methods of determining appropriate level, technique, prognosis. In: Rutherford RB, ed. Vascular Surgery, 3rd ed. Philadelphia: WB Saunders, 1989;150:1687-712. 12. Wagner FW. The Syme amputation. In: American Academy of Orthopedic Surgeons. Atlas of Limb Prosthetics: Surgical and Prosthetic Principles. St. Louis: CV Mosby, 1981:32640. 13. Harris WR, Silverstein EA. Partial amputations of the foot: a follow-up srudy. Can J Surg 1964;7:6-13. 14. Chang BB, Paty PSK, Shah DM, Kaufman JL, Leather RP. Results of infrainguinal bypass for limb salvage in patients with end-stage renal disease. Surgery 1990;108,4:742-7. 15. Dietzek AM, Gupta K, Kram HB, Wengerter KR, Veith FJ. Limb loss with patent infra-inguinal bypasses. Eur J Vasc Surg 1990;4:413-7. Submitted June 10, 1993; accepted Oct. 22, 1993.

DISCUSSION Dr. Frank J. Veith (New York, N.Y.). The authors have emphasized that aggressive measures to save limbs jeopardized by ischemic gangrene can be successful. They show that even when foot necrosis extends beyond the limits of a transmetatarsal amputation, unconventional amputations through the tarsal bones can lead to healing, provided a bypass has restored good distal arterial flow. This concept is by no means new. More than 20 years ago, we showed that extensive forefoot and heel gangrene involving the tarsal bones or the calcaneus could, after revascularization, be debrided and healing could be achieved with even more unconventional, unnamed forefoot amputations. Sometimes these were even combined with extensive skin grafting. John Ochsner talks about the funny-looking feet that resulted from these freestyle amputations. Nevertheless, these funny-looking feet proved to be quite functional in these patients. This is certainly worth reemphasizing because some surgeons still erroneously consider extensive forefoot or heel gangrene an indication for major amputation. There are many points in this study with which I agree. One is that with extensive gangrene, it is essential to restore full arterial pressure to foot arteries. Even with a foot pulse restored, however, infection and necrosis in the foot may be so extensive and persistent that the limb is lost. This is particularly common in patients with dia-

betes and kidney failure. Do you have any special tricks for achieving healing with extensive gangrene in renal failure patients 1 Do you use the freestyled no-named amputations, the debride and skin graft procedures that we have described. If there is loss of plantar skin or extensive heel gangrene, will you debride and graft these weight-bearing areas1 We find it very worthwhile, even if one has to remove most of the calcaneus. A final question concerns the high hospital costs we have had when these patients require several debridements or revisions. Have you studied length of stay and costs in your patients1 Dr. Reginald S. A. Lord (Sydney, Australia). About a year ago, I realized that flaps are constructed in amputations primarily to allow bone removal. Sadly, often the flaps themselves become ischemic and lead to further amputations. With this in mind, I modified my technique to avoid flaps altogether and now use flapless amputations for forefoot and digital amputations. The technique means that the surgeon simply cuts along the border of the viable and nonviable skin, removes all the soft tissue that is necrotic, and then, rather than reflecting back the flap to enable the bone to be resected, one simply drills out all the bone, with modified orthopedic and dental drills as necessary.

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With this technique, it's not necessary to use flaps or to reflect the soft tissue at all, and so far, with limited experience, we have found this technique useful. Have you used the drilling technique? What is the method you use for transsecting bone? Dr. George Andros (Burbank, Calif.). We ought not to lose sight of the fact that you can do even more limited amputations than ray amputations. Of late, we have been, rather than doing a formal ray amputation, merely making a dorsal or sometimes plantar incision on the foot, deboning the foot, and allowing these to granulate. It was my initial suspicion that these wouldn't heal, but if you're patient, you can actually do toe-sparing procedures, and that puts you at the other end of the spectrum. Who does these procedures. Do the vascular surgeons do them? Do the vascular surgeons do the prosthesis fitting and rehabilitation from beginning to end; and if you do, what is the role of the podiatrist and orthopedist in your practice? Do you have any experience with free flaps? Dr. Ethan L. Welch (Rochester, N.Y.). I have done about eight or 10 of the Pirogoff amputations and I find it a rather easy operation, contrary to the comment, and the only thing that's necessary is to be sure that the transverse cut in the calcaneus and the transverse cut in the distal part of the tibia are absolutely even. If you do that, you don't have to use any pins. Dr. Gary W. Gibbons (Boston, Mass.). I question your algorithm that you had in the beginning, in that you had antibiotics, then revascularization, and yet you lost five limbs to amputation because of sepsis. One of the things that I point out is that one of the most important things to do early is aggressive debridement and drainage of infection, especially in patients with diabetes, followed then with adjunctive antibiotics and your revascularization procedures, because with early aggressive debridement, you may actually be able to identity the patients with extensive sepsis. One of the things that we have learned with our podiatry colleagues is that preserving as much length of the foot, especially the first toe and metatarsal head, achieves a much better functioning foot and that once we've restored foot pulses, we're able to do much more limited debridement of infected bone and do fewer amputations. Dr. Benjamin B. Chang. We did not do this analysis with cost or length of stay in mind. This is an evolution over a IS-year period. These amputations were solely performed by Dr. Jacobs, who is the head of the orthopedics department at Albany Medical Center and who has a special interest in these amputations, both in patients requiring revascularizations and others. His methods are what we're presenting, and it is his work and knowledge and struggle that has lead to the algorithm that we've come to use. We agree that there are nonanatomic or un anatomic amputations that can be performed. Sometimes these are performed by us. However, we have found that more anatomic amputations in this cases, such as the ones

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discussed here, may well heal faster and more cleanly than debrided areas skin-grafted and left to granulate. And because of the pressure of length of stay, we've gone more to performing an anatomic-type bypass than an unanatomic amputation. That is not to say that these unanatomic amputations do not affect limb salvage also. With regard to Dr. Lord's comments, we cut the flaps before removing the bone. The bones are cut with a knife through the joint and a curved osteotome is used to remove the cartilaginous surface. It has not been necessary to drill out the bone as you have mentioned, although this seems to be an appropriate technique in some cases. With regard to Dr. Andros' comments, the amputations are performed solely by Dr. Jacobs. This is a transferrable skill, though, because at the VA hospital we end up performing these amputations ourselves. The prostheses are fitted by a single prosthetist who works in the area, and who worked very closely with Dr. Jacobs in the development of this type of prosthesis. With regard to the use of free flaps for this type of patient, this has been used not for patients with forefoot or midfoot necrosis, but has been used in our practice in a limited extent with patients with heel ulcers that do not respond to normal methods. With regard to Dr. Welch's comments, the Pirogov is not a difficult operation, but we do find it is more difficult than a Chopart, which is a very easy operation. In any case, I agree that the functional results of a Pirogoff amputation, at least qualitatively, is superior to that of a Syme amputation, because of the ability of the patient to ambulate without a prosthesis for short distances much better than with a Syme amputation. With regard to Dr. Gibbons' comments regarding our preoperative preparation of the patient, we make a point of not delaying the bypass for control of sepsis. And this is a very important point because we believe that making the patient wait for debridement and intravenous antibiotics and thereby delaying the revascularization can actually lead to furthering of the necrosis in that if you debride tissue that is not well revascularized, it may often die back. Therefore we almost always perform these revascularizations on these types of patients within 24 or, at most, 48 hours of the time of appearance. There is no effort made to "clear the infection" before revascularization. We believe that revascularized tissue clears an infection much faster than nonrevascularized tissue. It is incorrect that five of the limbs were lost with good revascularization and continued sepsis. In fact, none of these limbs were lost to continued sepsis. However, there are patients in this group who are diagnosed with extensive necrosis, and it is debatable whether the flaps will survive. These patients are typically aggressively revascularized, and an attempt to make the amputation is done later. However, I want to emphasize that prolonged infection in this case was not a problem, and we do not believe that delay of revascularization nor "control of infection," is necessary, useful, or beneficial for these patients.