1. Lower Limb Amputations –
Presented by
Letch Kline, M.D., FACS
Thoracic/General Surgeon
Gulf Coast Veterans Health Care System

2. Overview Integral part of general surgical practice.
The global lower extremity amputation study group
- wide variations in amputation rates worldwide
- similarities in age and sex distribution
- very high correlation with diabetes (BJS 2000)

3. Limb Loss Statistics
There are nearly 2 million people living with limb loss in the United States Approximately 185,000 amputations occur in the United States each year Nearly half of the individuals who have an amputation due to vascular disease will die within 5 years. Of persons with diabetes who have a lower extremity amputation, up to 55% will require amputation of the second leg within 2‐3 years

4. Indications for amputation:
Peripheral Vascular Disease
Failed revascularization
Extensive tissue loss
Unreconstructable
Excessive surgical risk

5. Indications for amputation:
Diabetes
Overwhelming sepsis
Extensive tissue loss
Excessive surgical risk

6. Indications for amputation:
Trauma
Crush
Nerve injuries
Others
Spina bifida
Contractures
Neuropathy
Bed bound

7. Goals of amputation: Remove all infected, necrotic and painful tissue
Achieve successful wound healing
Fashion an adequate stump for a prosthetic

8. Attempt limb salvage or primary amputation?
Extent of tissue loss in foot
Anatomy of reconstruction
Associated comorbidities
ESRD with heel gangrene – maybe best treated with primary amputation

9. Natural history of major amputation:
10% perioperative mortality
3 year survival after BKA – 57%; after AKA – 39%
Of 440 major amputations – 75 died in hospital, 113 deemed unsuitable for prosthesis. Of 57% referred for prosthesis – at 3years follow up a further 54 died, only 10-15% were mobile at home. (BJS 1992)

10. Amputation levels and significance:
Major amputation: above tarsal-metatarsal joint.
Levels
- BKA
- Through knee
- AKA
- Hip disarticulation

11. Amputation levels and significance:
BKA – maximal rehabilitation potential
% increase in energy expenditure
% of all BKAs go onto an AKA in 3 years
(5% perioperative mortality)
AKA – less rehab potential
% extra energy expenditure
- Better rates of healing

12. Level Selection: Subjective:
Clinical exam – skin quality, extent of ischemia/ infection
Pulses – presence of a pulse immedietly above the level of amputation – almost 100% chance of healing
“Clinical judgment” alone 80% accurate in predicting healing with BKA and 90% in AKA.
The need to maximize rehab potential and minimize need for revision has led to the investigation of optimal method of level selection.

13. Level Selection:
Wagner et al (J vasc surgery 1988): clinical judgment superior to objective assessments. More distal amputations can be achieved with clinical measures over objective studies.
Clinical judgment is central to amputation level selection.

14. Level Selection: Objective tests: Non invasive
Doppler pressures – maybe unreliable in diabetics; ankle pressures >60mm – >50% chance of BKA healing.

15. Level Selection Non invasive 2. Skin perfusion pressures
Radio isotope washout
Laser doppler velocimetry
<20mm Hg – 89% failure of healing

16. Level Selection Non Invasive 3. Transcutaneous oximetry
Tested under local hyperthermia
Correlates with true PaO2
Threshold value – 30mm

17. Level Selection:
Invasive – Angiographic scoring
Poor correlation

18. Level Selection

19. Conclusions:
Amputation is traumatic enough…poor level selection can make it worse.
Clinical judgement is central to proper level selection
Patient factors are more important than objective testing

20. References:
Lee, A. Vascular Fellow, Nepean Hospital. PPT presentation “Lower Limb Amputations: Level Selection”
Ziegler‐Graham K, MacKenzie EJ, Ephraim PL, Travison TG, Brookmeyer R. Estimating the Prevalence of Limb Loss in the United States: 2005 to Archives of Physical Medicine and Rehabilitation2008;89(3):422‐9.
Owings M, Kozak LJ, National Center for Health S. Ambulatory and Inpatient Procedures in the United States, Hyattsville, Md.: U.S. Dept. of Health and Human Services, Centers for Disease Control and Prevention, National Center for Health Statistics; 1998.
Robbins JM, Strauss G, Aron D, Long J, Kuba J, Kaplan Y. Mortality Rates and Diabetic Foot Ulcers. Journal of the American Podiatric Medical Association2008 November 1, 2008;98(6):489‐93.
Pandian G, Hamid F, Hammond M. Rehabilitation of the Patient with Peripheral Vascular Disease and Diabetic Foot Problems. In: DeLisa JA, Gans BM, editors. Philadelphia: Lippincott‐Raven; 1998.