Privacy and Personalisation A Private Sector Perspective Clive Humby October 2014.
Skin Graft With Humby Knife
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Transcript of Skin Graft With Humby Knife
Harvesting skin graft with Humby knife
Yong-June Kim26 June 2014
Outline
• Background: evolution of skin graft knife• Comparison of different types of Humby knife• Adjusting thickness• Thin vs thick skin graft
Background• L. Ollier of Lyon, France
(1872) – first successful large area (8cm2) graft using epidermis and dermis
– Included ½ thickness of the dermis
– “split graft”, “mid-thickness graft” etc. became split-thickness skin graft
Background• Original Humby knife (1932)
– First knife to introduce depth control– Rectangular framework, strapped to
limb– Needles attach the ends to stretch
the skin– Roller (guard) smoothed out the skin
in front
• Modified version– 2 years later– Guard fixed with screws– Width determined by pressure on
the knife
Comparison of different types
• Braithwaite (1955)– Guard slides, loosens
bearings– Skin rolls up around
the guard
• Watson (1960)– Fixed guard, rigid
bearings– “skin drag” from fixed
guard
Comparison of different types
• Cobette (1968)– Guard does not rotate
but slides: less drag– D-section in the guard
to prevent rolling of skin
Setting on Humby knife
• 1 bar = 0.25mm
• 0.05mm = 2/1000 inch– (approx)
• Therefore, 0.3mm = 12/1000 inch– 1.5 bar = approx 0.3mm
Adjusting thickness
• Pattern of bleeding in the donor area - thin vs thick
Thin skin graft
• Good– Resists infection better– Takes more easily– Allows donor site to heal quickly: 2nd harvest possible– Better scar in the donor site
• Bad– Worse color match– Contracts more– More difficult to attach
Thick skin graft• Full thickness skin graft (done with scalpel)
• Good– Less contraction, superior cosmetic result (use on the face)– More resistant to trauma (use on the palm of hand)
• Bad– Wound must be sterile for the graft to take place– Donor site must be closed (small harvest area)
• Harvest from– Behind ear (best color match with face)– Supraclavicular area– Anticubital fossa– Groin
Thank you