partial foot amputation in patients with diabetic foot ulcers

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DOI: 10.3113/FAI.2012.0707

2012 33: 707Foot Ankle IntMatthew L. Brown, Wan Tang, Amar Patel and Judith F. Baumhauer

Partial Foot Amputation in Patients with Diabetic Foot Ulcers

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FOOT & ANKLE INTERNATIONAL

Copyright 2012 by the American Orthopaedic Foot & Ankle SocietyDOI: 10.3113/FAI.2012.0707

Partial Foot Amputation in Patients with Diabetic Foot Ulcers

Matthew L. Brown, BA1; Wan Tang, PhD2; Amar Patel, MD3; Judith F. Baumhauer, MD, MPH1

Rochester, NY

ABSTRACT

Background: Transtibial amputations (TTA) are performed forrecalcitrant or infected ulcers of the midfoot, hindfoot, or ankle.This procedure results in decreased ambulatory status causedby increased oxygen demands and energy expenditure. Partialfoot amputations have the advantage of being an end-bearinglimb and require less work to walk, theoretically suggestingimproved functional outcome. The purpose of this research wasto examine the longevity, outcome, and mortality of partial footamputations as an alternative to TTA. Methods: Retrospectivechart review identified diabetic patients with transmetatarsal,Chopart’s, and calcanectomy amputations for osteomyelitis ornonhealing ulcers. A control group consisted of diabetic patientswho underwent TTA. A comparison between groups examinedmortality, proximal ipsilateral reamputation, and a validatedambulatory functional outcome measure. Results: Eighteen TTApatients were enrolled. The 5-year mortality rate was 0.45,one patient required reamputation, and the mean postoperativeambulatory score was 2.8. Twenty-one transmetatarsal patientswere enrolled. The 5-year mortality rate was 0.30, two patientsrequired reamputation, and the mean postoperative ambulatoryscore was 4.3. Ten Chopart’s amputation patients were enrolled.The 5-year mortality rate was 0.36, six patients required ream-putation, and the mean postoperative ambulatory score was4.3. Seventeen partial calcanectomy patients were enrolled. The

1University of Rochester School of Medicine and Dentistry, Rochester, NY.

2Department of Biostatistics and Computational Biology, University of RochesterMedical Center, Rochester, NY.

3Rockhill Orthopaedics, Lee’s Summit, MO.

No benefits in any form have been received or will be received from a commercialparty related directly or indirectly to the subject of this article.

Corresponding Author:Judith F. Baumhauer, MD, MPHDepartment of Orthopaedic SurgeryFoot and Ankle DivisionUniversity of Rochester School of Medicine and Dentistry601 Elmwood Avenue, Box 665Rochester, NY 14642E-mail: judy [email protected]

For information on pricings and availability of reprints, email [email protected] call 410-494-4994, x232.

5-year mortality rate was 0.69, six patients required reampu-tation, and the mean postoperative ambulatory score was 4.3.Sixteen total calcanectomy patients were enrolled. The 5-yearmortality rate was 0.59, five patients required reamputation,and the mean postoperative ambulatory score was 3.3. Conclu-sion: TTA is associated with high morbidity and mortality,which suggests that the advantage of partial foot amputationsshould be investigated. Only transmetatarsal amputations at 1and 3 years were statistically lower for mortality than TTA.Partial foot amputations at the other levels failed to show statis-tically improved survivorship. Transmetatarsal and Chopart’samputations had high ambulatory levels and the longest dura-bility, which suggests that these amputations may provide someambulatory advantage.

Level of Evidence: Therapeutic Level III

Key Words: Calcanectomy; Chopart’s Amputation; DiabetesMellitus; Transmetatarsal Amputation; Transtibial Amputation

INTRODUCTION

Foot ulcers represent a common and debilitating problemfor diabetic patients. Patients with diabetes face a 15% to25% lifetime risk of developing a foot ulcer and approx-imately 15% of these ulcers progress to osteomyelitis andrequire amputation.23,29,33,36 Infected foot ulcers are the mostcommon reason for hospital admission of a diabetic patient,accounting for one of every four admissions.34 Orthopaedicfoot and ankle surgeons often perform transtibial amputa-tions (TTA) to treat patients with recalcitrant foot ulcersof the midfoot, hindfoot, or ankle. This procedure unfor-tunately results in substantial postoperative morbidity andmortality. Ambulatory status is decreased following TTAbecause of physiologic and psychosomatic factors. Ineffi-cient biomechanics increase demand for energy, oxygen, andcardiac output.42,43 Motivation to ambulate may be limitedby the inconvenience, pain, or psychological stress that canbe associated with using a prosthetic or other assistive device.TTA increases demand on the contralateral limb, amplifyingthe risk of contralateral amputation. One-year mortality afterTTA has been reported to be 20.8% to 35.5%, with 5-yearmortality at 65%.3,19

707

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708 BROWN ET AL. Foot & Ankle International/Vol. 33, No. 9/September 2012

Diabetic patients with nonhealing foot ulcers may haveoperative alternatives to TTA that allow amputation on thelower extremity at a more distal level. Orthopaedic foot andankle surgeons perform transmetatarsal (TMA), Chopart’s,and calcanectomy amputations on patients with foot ulcerswho traditionally would have received a TTA. These proce-dures seek to salvage as much of the native foot and ankleas possible while allowing complete excision of necrotictissue, resulting in a stable soft tissue envelope after primaryclosure and an end-bearing limb. Studies exploring the workand oxygen consumption required for amputees to ambu-late have demonstrated that both parameters increase as thelevel of amputation becomes more proximal.14,42,43 Partialfoot amputations offer patients the chance for unassistedambulation on an end-bearing limb, with decreased energyexpenditure compared with a TTA.

The published results of partial foot amputations containsmall series that describe short-term survivorship; however,data on the mortality rates are sparse. McKittrick et al.first described transmetatarsal amputation as a limb salvagetechnique.26 Since his initial report, several investigatorshave examined using TMA as an alternative procedure.1,13,21,

26–28,32,38,40 Table 1 summarizes selected results.1,26,28,32,38

Francois Chopart first described amputation through thetalonavicular and calcaneocuboid joints in 1792. This ampu-tation has had limited use because of concern of post-operative equinovarus deformity. Although authors havedescribed operative techniques to prevent the equinovarusdeformity, results have been variable and widespread skepti-cism persists.8,9,12,20,22,24,35,38 Table 2 summarizes selectedresults.8,12,20,24 Calcanectomy was first described by Gaen-slen in 1931 as a salvage procedure for osteomyelitisof the calcaneus. Although not widely utilized, surgeonshave undertaken calcanectomy as treatment for diabeticpatients with nonhealing hindfoot ulcerations of the plantarsurface.4–6,10,11,15,37 Table 3 summarizes selected re-sults.4,6,10,11,15,37

The purpose of this study was to examine morbidity,mortality, proximal ipsilateral reamputation, and functionaloutcome in diabetic patients with recalcitrant foot ulcerstreated with partial foot amputations compared with diabeticpatients with TTA.

MATERIALS AND METHODS

Between January 1, 1995 and July 1, 2009, data wasretrospectively reviewed for patients who underwent TTA,transmetatarsal, Chopart’s, and calcanectomy (partial ortotal) amputations for nonhealing lower-extremity ulcerationsecondary to diabetes mellitus at one institution. Patientdemographics, lab chemistries, and outcome informationwith respect to mortality, proximal ipsilateral reamputation,and postoperative ambulatory status were collected for eachoperative procedure. Institutional Review Board approvalwas obtained.

Patients who underwent these procedures between Janu-ary 1, 1995 and July 1, 2009 were recruited from thepractices of three orthopaedic foot and ankle surgeons atone institution. The hospital billing database was accessedand an initial search was undertaken to identify patientsusing Current Procedural Terminology (CPT) codes: trans-metatarsal (28805), Chopart’s (28800), partial calcanectomy(28120), total calcanectomy (27674), and transtibial ampu-tation (27800, 27801). Charts were obtained and reviewedto confirm that patients had received the coded procedure.Medical history abstracted included age at surgery, Amer-ican Society of Anesthesiologists Physical Status (ASA-PS)score for the index procedure, hemoglobin A1c percentage(HbA1c), body mass index (BMI), and renal dialysis status.The ASA-PS score is a widely used, well-accepted, and vali-dated scoring system that assigns a score from one (best)to six (worst) to quantify a patient’s overall health statusbefore undergoing an operation independent of operativeor anesthesia risk.2,25,39 HbA1c percentages were recordedif documented in the hospital chart within 90 days of theindex amputation. Renal dialysis was recorded if a patienthad ever been dialyzed secondary to diabetes. Chi-squaretests were used for categorical variables and Kruskal-Wallistests, an extension of the nonparameteric Mann-WhitneyU test to three or more groups, were used for continuousvariables.

Mortality was the primary end point. The Social SecurityDeath Index was searched on July 1, 2009 and the date ofdeath was recorded for deceased patients. Followup time wasdefined as the period from the date of surgery until the dateof either death or study completion (July 1, 2009). Survivalanalysis was conducted for the primary end point data. AKaplan-Meier curve was estimated for each cohort with deathas the end point. Patients were censored if they were aliveat latest followup. Mortality rates based on survival analysismethods were calculated at 1, 3, and 5 years for each cohort.Log-rank test was applied to compare the survival curvesamong cohorts.

Secondary end points were proximal ipsilateral reamputa-tion and functional outcome. Operative and clinic notes werereviewed to identify patients who required proximal reampu-tation on the ipsilateral lower extremity. The date of surgerywas recorded only for the first reamputation after the indexamputation. Proximal reamputation rates and mean time tofailure were then calculated for each cohort. One investi-gator telephoned patients at the study conclusion to assessfunctional outcome. The Volpicelli ambulatory scale, a well-known, validated outcome measure, was used to score eachpatient’s current ambulatory status from zero to six. Table 4summarizes the Volpicelli scale.41 Outcomes for mortalityand longevity of the index partial foot amputation werecompared for patients with HbA1c < 8.0% and patientswith HbA1c ≥ 8.0%. Data were collapsed to include allpartial foot amputations for this analysis. All analyses wereaccording to intention to treat.

Copyright 2012 by the American Orthopaedic Foot & Ankle Society



Foot & Ankle International/Vol. 33, No. 9/September 2012 PARTIAL FOOT AMPUTATIONS FOR DIABETIC FOOT ULCERS 709

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Table 2: Summary of Studies That Have Examined Chopart’s Amputation as an Alternative to TTA

AuthorChopart’s

amputations DiabeticsEarly

mortalityLate

mortality

Earlyproximal

reamputation

Lateproximal

reamputationFunctional

status

Liebermanet al.24

43 84% 9 — — 17 Qualitative

Chang et al.8 59 83% — — 7 3 —DeGere &

Grady125 100% 1 (≤30 days) — 1 (≤30 days) 0 Qualitative

Krause et al.20 5 100% — — 0 0 Novel FunctionalScoring System∗mean postopscore: 1.4

RESULTS

Seventy-nine patients (82 feet) were enrolled. All patientshad diabetes mellitus. Age, ASA-PS score, HbA1c, andBMI were compared between cohorts and, with the numbersavailable, no significant difference could be detected. Asummary of results for all amputation groups is outlined inTable 5.

Eighteen patients with an index TTA were enrolled. Ageat surgery was 58.6 ± 12.3 years (mean ± SD), ASA-PSscore was 3.1 ± 0.6, HbA1c was 9.0 ± 2.0%, BMI was36.0 ± 11.5 kg/m2, and eight patients required renal dialysis.Eight patients died during the study period. Mortality ratesbased on survival analysis at 1, 3, and 5 years were 0.23,0.30, and 0.45, respectively (Figure 1, A through D). Onepatient required proximal ipsilateral reamputation, whichoccurred 0.1 years after the index TTA. Mean postoperativeVolpicelli ambulatory score was 2.8 ± 2.4 (Figure 2).

Twenty-one patients with an index TMA were enrolled.Age at surgery was 53.8 ± 12.8 years (mean ± SD), ASA-PS score was 3.0 ± 0.5, HbA1c was 8.8 ± 1.0%, BMI was30.8 ± 5.8 kg/m2, and five patients required renal dialysis.Seven patients died during the study period. Mortalityrates based on survival analysis at 1, 3, and 5 years were0.00, 0.05, and 0.30, respectively (Figure 1A). Two patientsrequired proximal ipsilateral reamputation, which occurred2.3 ± 2.8 years after the index TMA. Mean postoperativeVolpicelli ambulatory score was 4.3 ± 2.1 (Figure 2).

Ten patients with an index Chopart’s amputation wereenrolled. Age at surgery was 56.8 ± 12.6 years (mean ±SD), ASA-PS score was 2.8 ± 0.4, HbA1c was 8.2 ± 2.2%,BMI was 37.8 ± 6.7 kg/m2, and six patients required renaldialysis. Four patients died during the study period. Mortalityrates based on survival analysis at 1, 3, and 5 years were0.20, 0.30, and 0.40, respectively (Figure 1B). Six patientsrequired proximal ipsilateral reamputation, which occurred2.3 ± 1.4 years after the index Chopart’s amputation. Mean

postoperative Volpicelli ambulatory score was 4.3 ± 2.9(Figure 2).

Seventeen patients with an index partial calcanectomywere enrolled. Age at surgery was 53.4 ± 13.6 years (mean± SD), ASA-PS score was 2.8 ± 0.5, HbA1c was 8.3 ±1.3%, BMI was 33.8 ± 8.3 kg/m2, and six patients requiredrenal dialysis. Ten patients died during the study period.Mortality rates based on survival analysis at 1, 3, and 5 yearswere 0.12, 0.38, and 0.69, respectively (Figure 1C). Sixpatients required proximal ipsilateral reamputation, whichoccurred 0.7 ± 0.5 years after the index partial calcanec-tomy. Mean postoperative Volpicelli ambulatory score was4.3 ± 1.5 (Figure 2).

Sixteen patients with an index total calcanectomy wereenrolled. Age at surgery was 63.8 ± 13.0 years (mean ±SD), ASA-PS score was 3.2 ± 0.7, HbA1c was 8.2% (n =1), BMI was 27.9 ± 7.2 kg/m2, and eight patients requiredrenal dialysis. Eleven patients died during the study period.Mortality rates based on survival analysis at 1, 3, and 5 yearswere 0.38, 0.38, and 0.59, respectively (Figure 1D). Fivepatients required proximal ipsilateral reamputation, whichoccurred 0.3 ± 0.2 years after the index total calcanec-tomy. Mean postoperative Volpicelli ambulatory score was3.3 ± 3.1 (Figure 2).

Seventeen patients who received a partial foot amputationhad an HbA1c percentage documented within 90 days of theindex amputation; seven patients had an HbA1c < 8.0%and 10 had an HbA1c ≥ 8.0%. Regarding mortality, fourof seven patients with HbA1c < 8.0% were deceased atstudy conclusion, which was more than four deaths amongthe ten patients with HbA1c ≥ 8.0% (Figure 3A). Withrespect to longevity, the index amputation failed in threeof seven patients with HbA1c < 8.0%, which was less thansix failures among the 10 patients with an HbA1c ≥ 8.0%(Figure 3B).





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Table 4: Summary of Validated Instrument Used to Assess Functional Outcome

Grade Description

6 Unlimited Community Ambulator: Walks at least 5 blocks; uses a wheelchair for longer distances; may use acane or crutches; and is able to negotiate independently on stairs without rails, on curbs, on rough terrain,and on public transportation.

5 Limited Community Ambulator: Walks 1 to 5 blocks; uses a wheelchair for longer distances; may use a caneor crutches; and is able to negotiate independently on stairs without rails, on curbs, on rough terrain, and onpublic transportation.

4 Unlimited Household Ambulator: Walks at least 100 feet in the house; uses a wheelchair for longer distancesoutside the house; may use a cane, crutches, or a walker; and is able to negotiate independently on stairswith rails, on carpets, and in and out of chairs.

3 Limited Household Ambulator: Walks less than 100 feet in the house; uses a wheelchair for longer distancesoutside the house; may use a cane, crutches, or a walker; and is able to negotiate independently on stairswith rails, on carpets, and in and out of chairs.

2 Supervised Household Ambulator: Needs supervision during limited walking in the house.1 Wheelchair Ambulator: Uses a wheelchair at all times and is able to transfer to and propel the wheelchair.0 Bedridden: Confined to bed or unable to transfer or propel a wheelchair.

Table 5: Summary of Results for All Experimental Index Groups in Current Study Including Transtibial Amputation,Transmetatarsal, Chopart’s, Partial Calcanectomy, and Total Calcanectomy

TTA Transmetatarsal ChopartPartial

calcanectomyTotal

calcanectomy

Patients 18 21 10 17 16Age [years]a 58.6 ± 12.3 53.8 ± 12.8 56.8 ± 12.6 53.4 ± 13.6 63.8 ± 13.0ASA-PS Scorea 3.1 ± 0.6 3.0 ± 0.5 2.8 ± 0.4 2.8 ± 0.5 3.2 ± 0.7HbA1c [%]a 9.0 ± 2.0 8.8 ± 1.0 8.2 ± 2.2 8.3 ± 1.3 8.2 (n = 1)BMI [kg/m2]a 36.0 ± 11.5 30.8 ± 5.8 37.8 ± 6.7 33.8 ± 8.3 27.9 ± 7.2Renal dialysis 8 5 6 6 8Deaths 8 7 4 10 111-year mortality rate 0.23 0.003 0.2 0.12 0.383-year mortality rate 0.30 0.05b 0.3 0.38 0.385-year mortality rate 0.45 0.3 0.4 0.69 0.59Proximal reamputations 1 2 6 6 5Time to proximal

reamputation [years]0.1 (n = 1) 2.3 ± 2.8 2.3 ± 1.4 0.7 ± 0.5 0.3 ± 0.2

Postoperativeambulatory status

2.8 ± 2.4 4.3 ± 2.1 4.3 ± 2.9 4.3 ± 1.5 3.3 ± 3.1

a, Indicates mean ± standard deviation.b, Indicates statistically significant (p < 0.05) difference compared to corresponding TTA mortality.

DISCUSSION

Transtibial amputation is a common surgery for nonhealingfoot ulceration and osteomyelitis in patients with diabetes.The high morbidity and mortality associated with TTAsuggest that it would be valuable to investigate alternative

procedures to treat these problems. Partial foot amputations

may offer advantages compared with TTA.

Transmetatarsal amputation resulted in low morbidity and

mortality in this study and therefore TMA offers a good

alternative to TTA in selected patients with limited disease.





Fig. 1: Kaplan – Meier survival analyses: comparison of TMA survival to TTA (A), Chopart’s survival to TTA (B), partial calcanectomy survival to TTA (C),and total calcanectomy to TTA (D). Patients were censored (tick mark) if they were alive at latest followup.

Fig. 2: Volpicelli ambulatory score. The Volpicelli ambulatory score is avalidated outcome used to assess functional outcome. For each cohort, themean Volpicelli ambulatory score is plotted with error bars for standarddeviation. No statistically significant differences were detected betweencohorts. BKA, below-knee amputation.

Mortality was lower for the TMA cohort compared with theTTA cohort at every followup interval; however, statisticalsignificance was achieved only at 1 year (0.00 versus 0.23,p < 0.05) and 3 years (0.05 versus 0.30, p < 0.05). TMAalso appears to provide stability with healing similar to TTA.The reamputation rate in the TMA cohort was 0.09, which

was minimally higher compared with the TTA rate of 0.06.The two proximal ipsilateral reamputations occurred at 0.3and 4.2 years from the index TMA, but only the failureat 0.3 years was in the early postoperative period. Finally,transmetatarsal amputation appears to offer an importantfunctional advantage compared with TTA. The mean Volpi-celli ambulatory score of 4.3 achieved in our TMA cohortcompares favorably to a mean score of only 2.8 for ourTTA controls. Transmetatarsal amputation appears to offera predictable, durable, and functional operative alternative toTTA for select patients.

Chopart’s amputation resulted in morbidity and mortalitycomparable to TTA but provided the advantage of an end-bearing limb with improved functional outcome. Althoughthe literature provides very limited information regardingmortality following Chopart’s amputation in diabetic patients,our results appear comparable to those reported by Stoneet al.38 Stone’s data may be biased because their protocolutilized Chopart’s amputation only as salvage for failedTMA.38 Although the 0.60 reamputation rate in our Chopart’scohort was substantially higher than the 0.06 rate for TTA,the Chopart’s amputation proved relatively durable. Whena Chopart’s amputation failed, the mean time to proximalreamputation was 2.3 years. The mean Volpicelli ambulatory





Fig. 3: Outcomes of partial foot amputations stratified according tohemoglobin A1c percentage: comparison of mortality after partial footamputation for patients with HbA1c < 8.0% to patients with HbA1c ≥8.0% (A) and longevity of the index partial foot amputation for patientswith HbA1c < 8.0% to patients with HbA1c ≥ 8.0% (B).

score of 4.3 for our Chopart’s cohort compares favorablywith the TTA score of 2.8. Compared with TTA, the potentialfor improved functional outcome associated with Chopart’samputation must be weighed against the markedly higherproximal reamputation rate for Chopart’s. In summary,Chopart’s amputation appears to offer improved functionaloutcome but is less predictable in longevity compared withTTA.

Syme’s ankle disarticulation has been advocated as analternative to Chopart’s amputation in diabetic patients withcertain types of plantar foot ulcers.31 Appropriate candi-dates would include only patients with ulcers considered(1) too large to permit complete excision and soft tissuecoverage with TMA and (2) to have sufficient heel padsparing so a stable distal weightbearing surface could befashioned. Syme’s disarticulation provides mortality benefitcompared to TTA. One study reported that only 30 of97 patients died during follow-up, with average time todeath of 57.1 months.31 The expected postoperative coursewith Syme’s disarticulation appears intermediate to TTAand Chopart’s. Postoperative infection developed in 22.7%(22 of 97) of patients after Syme’s disarticulation and 15.5%(15 of 97) ultimately failed to achieve wound healing andwould presumably require a proximal reamputation.31 Ambu-latory function postoperatively was quite good, with 48.8%(40 of 82) of patients with healed Syme’s disarticulation

being rated as “community walkers.”31 Methods were notidentical but functional outcomes appear similar for Syme’sand Chopart’s level amputations. The work of Waters andothers suggests a theoretical advantage in terms of energyconsumption of Chopart’s amputation compared with Syme’sdisarticulation because the Chopart’s level provides an end-bearing limb and preserves ankle mobility; however, morerecent work questions whether Waters’ principle that moredistal amputations conserve energy applies to partial footamputations.14,17,42,43 Whether amputation level correlatesto the amount of activity a patient chooses to undertake isunknown. In summary, while a Syme’s ankle disarticulationhas an important place in the armamentarium of surgeonswho treat diabetic patients with foot ulcerations, the compar-ison between a Syme’s amputation and other partial footamputations, such as a Chopart’s level surgery, was notundertaken in this study. The number of patients with aSyme’s level amputation was too few for comparison. Ulti-mately, a prospective, multi-institutional study will be neededto better understand how outcomes differ and to help toinform patient selection.

In our experience, partial calcanectomy resulted in rela-tively high morbidity and mortality compared with TTA.Analysis of our data and the limited data available in the liter-ature seems to indicate that partial calcanectomy performswell over the short term, up to several months postopera-tively, but then does poorly thereafter. The 1-year mortalityrate of 0.12 in our cohort falls between the 1-year mortalityrates reported by Cook et al. (0.07) and by Bollingerand Thordarson (0.22).6,10 Over longer followup intervals,mortality rates in our cohort were higher compared with ratesreported by Cook et al.10 Similarly, when viewed againstour control TTA cohort, partial calcanectomy performed wellinitially but poorly over the long term. Mortality rates at 1-year followup demonstrated decreased mortality for partialcalcanectomy compared with TTA (0.12 versus 0.23), butthis was not statistically significant (p = 0.38).

Conversely, partial calcanectomy resulted in higher mor-tality rates compared with our TTA cohort at both 3- and5-year followup periods, although not statistically signifi-cant. In our experience, partial calcanectomy was associatedwith a markedly higher reamputation rate compared withTTA (0.35 versus 0.06) and reamputation was required ata mean of 0.7 years after a failed index partial calcanec-tomy. When partial calcanectomy healing was achieved, itresulted in a good functional outcome postoperatively, witha mean ambulatory score of 4.3, which compares favorablywith the mean score of 2.8 in our TTA cohort. The finalanalysis suggests that partial calcanectomy provides ques-tionable advantage compared with TTA. Although partialcalcanectomy offers the prospect of an end-bearing limband improved postoperative functional status it has (1) anunpredictable postoperative course, (2) an amputation ofquestionable durability, and (3) an increased mortality rateover the longer term.





Total calcanectomy only accentuates the problems associ-ated with partial calcanectomy. Mortality was increased fortotal calcanectomy compared with TTA at all followup inter-vals; however, the increases were not statistically significant.Proximal ipsilateral reamputation rate for total calcanectomywas considerably higher than the TTA rate (0.31 versus0.06), and when higher-level amputation was required, itwas required very quickly, at a mean of 0.3 years from theindex total calcanectomy. Thus total calcanectomy suggestsan even less favorable risk-to-benefit ratio compared withpartial calcanectomy for durability and longevity.

The less favorable results seen with calcanectomy arenot surprising given that heel ulceration suggests worsedisease severity compared with ulcers located on the toesor the plantar surface of the foot underneath the metatarsalheads.7,16,18,44 Cevera et al. reported that limb salvage istwo to three times less likely for heel ulcers compared withmetatarsal ulcers.7 In a large cohort of patients with diabetes,Gershater et al. found that patients with ulcers on the heelhad higher rates of both major amputation (7.3%) and death(19.8%) compared with patients with toe ulcers (major ampu-tation, 6.2%; death, 13.1%) and with plantar ulcers (majoramputation, 2.8%; death, 12.9%).16 The exact pathophysio-logical mechanisms contributing to more severe disease andworse prognosis in heel ulceration are complex and not wellunderstood at this time. Finally, the worse outcomes withtotal compared with partial calcanectomy were expected,given that the surgeon’s decision to perform total rather thanpartial calcanectomy depends almost exclusively on ulcersize and severity of involvement.

There has been considerable interest in the literaturefor determining markers that are associated with successfuloperative outcomes in patients with diabetic foot ulcers.Pinzur et al. examined the value of preoperative serumalbumin, blood lymphocyte count, and Doppler ischemicindex for predicting operative outcomes of partial footamputations in ischemic patients with and without diabetes.30

More recently, attention has focused on the impact thathyperglycemia might have on operative outcome. Youngeret al. examined risk factors for failure of transmetatarsalamputation and concluded that only HbA1c was significantlyhigher (p < 0.001) in failed compared with intact TMAs.45

Interestingly, Jones and Marshall found that HbA1c hadno statistically significant impact on mortality in a cohortof 80 diabetic patients who underwent lower-extremityamputations.19 In line with Younger’s conclusion, our datasuggest that a partial foot amputation is more likely tofail in patients with an HbA1c ≥ 8.0%. However, wefound that proportionately more patients died followinga partial foot amputation in the group with HbA1c <

8.0% compared with the group with HbA1c ≥ 8.0%. Onepossible explanation for this apparently paradoxical findingis that survival of the index amputation represents a shorter-term outcome compared with mortality. Thus HbA1c valuesobtained within 90 days of the index procedure may be

more sensitive during the early postoperative period in whichhealing must occur but is relatively less sensitive for theoutcome of mortality, which generally has a longer timehorizon and would tend to be more multifactorial. The majorlimitations of this study include the retrospective designand small numbers in each cohort. The retrospective designquestions whether patients in each cohort were comparable,the limitations with the number of variables examined, andthe role of surgeon or patient bias in the cohort composition.Statistical analyses were limited by the relatively smallsubject numbers and prohibited formal analysis of underlyingfactors associated with end points. The considerable loss offollowup for ambulatory status, which was caused mainlyby high mortality rates and nonworking telephone numbers,may limit the generalizability of reported ambulatory statusoutcomes. We believe this study provides information notcurrently available in the literature regarding mortality,reamputation rates, and functional outcome for alternativepartial foot amputations in diabetic patients. This work willprovide operative insight on amputation levels and importantoutcome measures for patients. This information may behelpful in counseling and educating patients with informeddecision making regarding these treatment options.

Our study has shown that transmetatarsal and Chopart’samputations may offer good operative alternatives to TTAin patients with diabetes mellitus who develop foot ulcera-tions. Both amputations offer decreased mortality rates andthe chance to retain an end-bearing limb, leading to improvedpostoperative ambulation. These benefits, however, comeat the potential risk of a subsequent proximal ipsilateralamputation, particularly with Chopart’s amputations occur-ring within 3 years.

REFERENCES

1. Anthony, T; Roberts, J; Modrall, JG; et al.: Transmetatarsalamputation: assessment of current selection criteria. Am J Surg.192:e8 –11, 2006. http://dx.doi.org/10.1016/j.amjsurg.2006.08.011

2. Aronson, WL; McAuliffe, MS; Miller, K: Variability in the AmericanSociety of Anesthesiologists Physical Status Classification Scale.AANA J. 71:265, 2003.

3. Aulivola, B; Hile, CN; Hamdan, AD; et al.: Major lower extremityamputation: outcome of a modern series. Arch Surg. 139:395 –399;discussion 399, 2004. http://dx.doi.org/10.1001/archsurg.139.4.395

4. Baravarian, B; Menendez, MM; Weinheimer, DJ; et al.: Subtotalcalcanectomy for the treatment of large heel ulceration and calcanealosteomyelitis in the diabetic patient. J Foot Ankle Surg. 38:194, 1999.http://dx.doi.org/10.1016/S1067-2516(99)80052-0

5. Baumhauer, JF; Fraga, CJ; Gould, JS; Johnson, JE: Totalcalcanectomy for the treatment of chronic calcaneal osteomyelitis. FootAnkle Int. 19:849, 1998.

6. Bollinger, M; Thordarson, DB: Partial calcanectomy: an alternativeto below knee amputation. Foot Ankle Int. 23:927, 2002.

7. Cevera, JJ; Bolton, LL; Kerstein, MD: Options for diabetic patientswith chronic heel ulcers. J Diabetes Complications. 11:358 –366, 1997.http://dx.doi.org/10.1016/S1056-8727(96)00125-0

8. Chang, BB; Bock, DE; Jacobs, RL; et al.: Increased limb salvage bythe use of unconventional foot amputations. J Vasc Surg. 19:341 –348;





discussion 348 –349, 1994. http://dx.doi.org/10.1016/S0741-5214(94)70109-1

9. Christie, J; Clowes, CB; Lamb, DW: Amputations through the middlepart of the foot. J Bone Joint Surg Br. 62:473 –474, 1980.

10. Cook, J; Cook, E; Landsman, AS; et al.: A retrospective assessmentof partial calcanectomies and factors influencing postoperative course.J Foot Ankle Surg. 46:248 –255, 2007. http://dx.doi.org/10.1053/j.jfas.2007.03.016

11. Crandall, RC; Wagner, FW, Jr: Partial and total calcanectomy: areview of thirty-one consecutive cases over a ten-year period. J BoneJoint Surg Am. 63:152 –155, 1981. PMid:7451518

12. DeGere, MW; Grady, JF: A modification of Chopart’s amputationwith ankle and subtalar arthrodesis by using an intramedullary nail.J Foot Ankle Surg. 44:281 –286, 2005. http://dx.doi.org/10.1053/j.jfas.2005.04.014

13. Dudkiewicz, I; Schwarz, O; Heim, M; Herman, A; Siev-Ner, I:Trans-metatarsal amputation in patients with a diabetic foot: reviewing10 years experience. Foot (Edinb.) 19:201 –204, 2009.

14. Gailey, RS; Wenger, MA; Raya, M; et al.: Energy expenditure oftrans-tibial amputees during ambulation at self-selected pace. ProsthetOrthot Int. 18:84, 1994.

15. Geertzen, JHB; Jutte, P; Rompen, C; Salvans, M: Calcanectomy,an alternative amputation? Two case reports. Prosthet Orthot Int. 33:78,2009. http://dx.doi.org/10.1080/03093640802419163

16. Gershater, MA; Londahl, M; Nyberg, P; et al.: Complexity offactors related to outcome of neuropathic and neuroischaemic/ischaemicdiabetic foot ulcers: a cohort study. Diabetologia. 52:398 –407, 2009.http://dx.doi.org/10.1007/s00125-008-1226-2

17. Goktepe, AS; Cakir, B; Yilmaz, B; Yazicioglu, K: Energy expenditureof walking with prostheses: comparison of three amputation levels. Pros-thet Orthot Int. 34:31 –36, 2010. http://dx.doi.org/10.3109/03093640903433928

18. Goudie, EB; Gendics, C; Lantis, JC, II: Multimodal therapy asan algorithm to limb salvage in diabetic patients with large heelulcers. Int Wound J. 9:132 –138, 2012. http://dx.doi.org/10.1111/j.1742-481X.2011.00869.x

19. Jones, RN; Marshall, WP: Does the proximity of an amputation, lengthof time between foot ulcer development and amputation, or glycemiccontrol at the time of amputation affect the mortality rate of people withdiabetes who undergo an amputation? Adv Skin Wound Care 21:118,2008. http://dx.doi.org/10.1097/01.ASW.0000305419.73597.5f

20. Krause, FG; Aebi, H; Lehmann, O; Weber, M: The ”flap-shaft”prosthesis for insensate feet with Chopart or Lisfranc amputations.Foot Ankle Int. 28:255 –262, 2007. http://dx.doi.org/10.3113/FAI.2007.0255

21. Krause, FG; deVries, G; Meakin, C; Kalla, TP; Younger, ASE:Outcome of transmetatarsal amputations in diabetics using antibioticbeads. Foot Ankle Int. 30:486, 2009. http://dx.doi.org/10.3113/FAI.2009.0486

22. Letts, M; Pyper, A: The modified Chopart’s amputation. Clin OrthopRelat Res. 256:44 –49, 1990.

23. Levin, ME; O’Neal, LW; Bowker, JH; Pfeifer, MA: In: Levin andO’Neal’s The Diabetic Foot. 7th ed. Philadelphia, PA, Mosby Elsevier,2008, p. 648.

24. Lieberman, JR; Jacobs, RL; Goldstock, L; Durham, J; Fuchs,MD: Chopart amputation with percutaneous heel cord lengthening. ClinOrthop Relat Res. 296:86 –91, 1993.

25. Macario, A; Schilling, P; Rubio, R; Goodman, S: Economics of one-stage versus two-stage bilateral total knee arthroplasties. Clin OrthopRelat Res. 414:149 –156, 2003. http://dx.doi.org/10.1097/01.blo.0000079265.91782.ca

26. McKittrick, LS; McKittrick, JB; Risley, TS: Transmetatarsalamputation for infection or gangrene in patients with diabetes mellitus.Ann Surg. 130:826 –840, 1949. http://dx.doi.org/10.1097/00000658-194910000-00019

27. Moxey, PW; Hofman, D; Hinchliffe, RJ; et al.: Epidemiological studyof lower limb amputation in England between 2003 and 2008. Br J Surg.97:1348 –1353, 2010. http://dx.doi.org/10.1002/bjs.7092

28. Mueller, MJ; Allen, BT; Sinacore, DR: Incidence of skinbreakdown and higher amputation after transmetatarsal amputation:implications for rehabilitation. Arch Phys Med Rehabil 76:50 –54, 1995.http://dx.doi.org/10.1016/S0003-9993(95)80042-5

29. Oyibo, SO; Jude, EB; Tarawneh, I; et al.: The effects of ulcersize and site, patient’s age, sex and type and duration of diabeteson the outcome of diabetic foot ulcers. Diabet Med. 18:133, 2001.http://dx.doi.org/10.1046/j.1464-5491.2001.00422.x

30. Pinzur, M; Kaminsky, M; Sage, R; Cronin, R; Osterman, H:Amputations at the middle level of the foot. A retrospective andprospective review. J Bone Joint Surg Am. 68:1061 –1064, 1986.

31. Pinzur, MS; Stuck, RM; Sage, R; Hunt, N; Rabinovich, Z: Symeankle disarticulation in patients with diabetes. J Bone Joint Surg Am.85:1667 –1672, 2003.

32. Pollard, J; Hamilton, GA; Rush, SM; Ford, LA: Mortality andmorbidity after transmetatarsal amputation: retrospective review of 101cases. J Foot Ankle Surg. 45:91, 2006. http://dx.doi.org/10.1053/j.jfas.2005.12.011

33. Ramsey, SD; Newton, K; Blough, D; et al.: Incidence, outcomes, andcost of foot ulcers in patients with diabetes. Diabetes Care 22:382, 1999.http://dx.doi.org/10.2337/diacare.22.3.382

34. Richard, J; Schuldiner, S: [Epidemiology of diabetic foot problems].Rev Medecine Interne. 29(suppl 2):S222, 2008. http://dx.doi.org/10.1016/S0248-8663(08)73949-3

35. Roach, JJ; Deutsch, A; McFarlane, DS: Resurrection of theamputations of Lisfranc and Chopart for diabetic gangrene. Arch Surg.122:931 –934, 1987. http://dx.doi.org/10.1001/archsurg.1987.01400200081015

36. Singh, N; Armstrong, DG; Lipsky, BA: Preventing foot ulcers inpatients with diabetes. JAMA 293:217 –228, 2005. http://dx.doi.org/10.1001/jama.293.2.217

37. Smith, DG; Stuck, RM; Ketner, L; Sage, RM; Pinzur, MS: Partialcalcanectomy for the treatment of large ulcerations of the heel andcalcaneal osteomyelitis. An amputation of the back of the foot. J BoneJoint Surg Am. 74:571 –576, 1992.

38. Stone, PA; Back, MR; Armstrong, PA; et al.: Midfoot amputationsexpand limb salvage rates for diabetic foot infections. Ann Vasc Surg.19:805 –811, 2005. http://dx.doi.org/10.1007/s10016-005-7973-3

39. The American Society of Anesthesiologists: ASA Physical StatusClassification System, 2009.

40. Toursarkissian, B; Hagino, RT; Khan, K; et al.: Healing of trans-metatarsal amputation in the diabetic patient: is angiography predictive?Ann Vasc Surg. 19:769 –773, 2005. http://dx.doi.org/10.1007/s10016-005-7969-z

41. Volpicelli, LJ; Chambers, RB; Wagner, FW: Ambulation levels ofbilateral lower-extremity amputees. Analysis of one hundred and threecases. J Bone Joint Surg Am. 65:599, 1983.

42. Ward, KH; Meyers, MC: Exercise performance of lower-extremityamputees. Sports Med. 20:207, 1995. http://dx.doi.org/10.2165/00007256-199520040-00001

43. Waters, RL; Perry, J; Antonelli, D; Hislop, H: Energy cost of walkingof amputees: the influence of level of amputation. J Bone Joint SurgAm. 58:42, 1976.

44. Younes, NA; Albsoul, AM; Awad, H: Diabetic heel ulcers: a majorrisk factor for lower extremity amputation. Ostomy Wound Manage. 50:50 –60, 2004.

45. Younger, AS; Awwad, MA; Kalla, TP; de Vries, G: Risk factorsfor failure of transmetatarsal amputation in diabetic patients: a cohortstudy. Foot Ankle Int. 30:1177 –1182, 2009. http://dx.doi.org/10.3113/FAI.2009.1177




partial foot amputation in patients with diabetic foot ulcers

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