US2435278A

US2435278A - Dermatome

Info

Publication number: US2435278A
Application number: US579196A
Authority: US
Inventors: George J Hood
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-02-22
Filing date: 1945-02-22
Publication date: 1948-02-03
Anticipated expiration: 1965-02-03

Description

Feb 3,, 348, as. HOQD 2,4352% DERMATQME Filed Feb. 22, 1945 ZSheets-Sheet l F50 INVENTOR.

flea/ye J #004 Fe, 194, JQH I 2,4352? DERMATOME Filed Feb. 22, 1945 2 Sheets-Sheet 2 1N VEN TOR.

Pdtented Feb. 3,1948 e NK'IYED STATES P QFFICEM W v, PEfiMATQME J fiwril i vrefi Km" asefittmitime mam-t. (o1.1 2c '3o.5)' rnhismventionr latesflto SHIgi fiL ePHIign m ab m k ettersratemmareimw gab-l; mammmf 5km vinstrumentsofia q tr er 'lm-W H-knowri in the. art and meaicaipm, afife; .t ynewand;t as;for itsprimarwobie ittq loa fession. H I we mmemems m dermaitomesqfi ei nta eauss s li siarising from the-use telifidfsefosed in U: S;- Letters Patent No. oilsuch gld g e frilgliicmSpeedvv i, p qm zzagmgiissmdemiv '1'. 1942i iormitx-nog-skin mit-rabilityito p uduceand geldrmafiompafiording greatenvisibi-lity du zmg; heietofore been possible, and the capacity of the theopemtiom, providing. simple, easily mampo apparatus fpr; excising skinv m a, mannex: to. Table mousing the necessity of= makingi zadg- 1-0. toa void'. undueim'mv tothepatientflandito insure- Insfimentswexcepting,to-oet tome thickness 9; a retum "offithe1tzeated; areato normalcy in a flfi m mMm e m n t r ma tain mm f m mt m m Qf The refinements" 1? ne-t e severineed e of, he-o fiti b1ad m a -on fil n-ii i i the m a e iv nrpflaitionitasfihfi--d stanqebetvveeothe sag; drawing even furtlgen eriha'noe, the effectiveness eltfgeandliamuam face of th -emit holder is .a 1- 15 and. desirability of the si1ccesstul dermatne tetedittolesfiebliehevgraiftvtmckness. shown i'n U'. SgLeL e atentNor 2,238,109. r

Further anditimpontant specific obje ts gf ith Injthefo gt gmvenmon chosen mums iaventionconmrisetheprovision.otnovel,unique fixation, time pumeml}, HL broadly designate; a. minositilvethladeholding stmoturegebutm m holden -iormed a single piece of metal cast o1; fon...DrecIuding-;=the sharpened eag t r the-blade 2 ot nw wtrimdu d n 'n sh "hav ng; from eventeomingintorcontact with'thmsmfiacean ar a mmQvr whic the adhesive qf;,theugrajt holdev; mean f r i di tin g mp stance for gripping and lifting the skinis-s-preadig graitithicknessvasg-theparts-of the dermatome are A r n d--.- i position at the axis, of

nositi'veiyet easily releasable. d g g my: amuate face l 4 2mg is .joi-ne d. to shoe 12- by a tra'risanestlng the outting. lolede me11inmccleten 2i verse wall; lildieposedionfthe medial-plane of the; mihedyositi'ons; and -apparatusipn holdinggthe wi eni g G p isl slightly shoxter'i-n length: oufitlhg fil'adein a pqsition; wher wthe samg jsa thanshoe l2; andpr'c g];eosively decreases in diam, quicklymovedito andkfxomthe operative positio 8 a h ;nd 2 211 6 @mw ch from its an i i; Gtlien .al-mswt the inv nti 11; 111 1 veri'sev center orthe" point wherewall [-8- merges fimcoorse'omhe{allowing.spefiificaitionrreterrmg fi e W f -a q v r i to flie aceempanyingdnatwing ,wherein: 1 gr n 16 a .beerinesm at each end-there- :--':F'Y -':1-ri5 ane:end: eIe-vational-.;view ot-; a derm o -rwiv she Wp longitudinal. W tomeomad ez emhgdy th e, fg ese nt, jnyenfien ciprocatiomot said shaft during the operation.- I In.

Fig. 2 i an l vati l i m g: 5m the event holder I0 is produced from somelight denmatomeopnos teztetth s c n i xFiem -ij ssm -i fifi abl? w t a d Precision side;elevationel; view of-th zd nmw i i is lewna e 7 Withstand friction; tbmewi-fih partsbroken away to reveal stmctumls bfi i a -W4 b i illustrated in features -e .1 4;: with h -(1 a e e i '5' is preferably. St-313612088 sectional view taken outline ho ow-t .F;W ,'ght' n -e t s grip fits w flz m i f jgi g if" w pgligygflthe lga gd the;fingersof the surgeon. will; Fig. 5 is a detailed sectional view taken Aline ext mt-t eii eer- Si w W 1==l8- and he y D v llagoi mgp & and. looking. in; dire ctign of qllidj ecidentallongitndinaldisplacement-of the theamowsc; entaw detailed sectional-viewv twinaut; eac ndtrespcctivelyg takemontlme'mwvkof fiei 2=.;---,- WIJ Q Q Q wh c lmn laer -w e lv n e ral w th mg g m m detailed; actienalf. W shaft 22 and in a position eccentric to the axis; woman: a modifledvform of a portion of; the: or: therv ha f n these pins Permits dwnatonie. l i I blade with respect-to arcuate surface IA of shoe:

citoneeud otzitheedermatomemadem accordaixce w 1 Y i itt1\- ;-tfimodifiefermothednventionyand; vun tin b lfi dlaZ8 mounted? on a frame'com- Fig. 9 is a n'etspective view of the dermatom'e: prising-., armsv 3&- and-tie-rod 32, vis in parallelism ilinstratedcimmgs; 11- 130 6 inclusive,

Witt: the-axesoizshaitlland pins 26. The arms? #:E-THQa-generam?eonstmctionomd method; ofiiemiflzjoumal pins zfi respectively. and-extend radially demomesoil the-type disclosed? in; my fromtheinfsupponting' ends: to heads; each'hav-e movement; oithe hereinaiter described cutting;

ing a slot 38 therein. These heads are cast integrally with their respective arms 38 and each has a set screw 38 entering a, tapped opening 48 which communicates with a. slot 36.

Cutting blade 28 extends into slot 38 when moved to the operative position and after it is placed, set screws 38 are tightened.

A pressure plug 42 disposed between the in ner end of each set screw 38 respectively and the face of cutting blade 28, prevents .mal-adjustment of blade 28 as the screws are tightened.

This pressure plug is shown in detail in Fig. 6

and comprises a short length of cylindrical stock having a conical or rounded upper end opposed to the end of set screw 38 to reduce the area of contact therebetween. Thus, when set screw 38 is turned, pressure plug 42 follow the turning motion and will be forced directly against blade 28. The end of set screw 38 may be rounded or tapered, in lieu of tapering the upper end of plug 42, if desired, to accomplish the object of preventing the transmittal of tightening movement to blade 28.

Each arm 38 has its head offset from the longitudinal axis to present an abutment 44 against which the sharpened edgeof cutting blade 28 is moved when the said blade is slipped into slots 36. This abutment surface 44 is arcuate and concentric with the arcuate face l4 of holder l8. Thus, regardless of the width of the blade or the condition of the main portion of its body, the sharpened edge will alwaysbe a uniform distance from face I 4 and will never ice allowed to come into content therewith.

After blade 28 is in the operative position with its cutting edge against abutments 44, one.of which is at each end of the blade and at the end of each arm 38, the thickness of graft may be determined by altering the distance through manipulation of member 46, rigid to shaft 22 and plate 48 between which one arm 38 extends, as illustrated in Figs. 2, 3 and 5.

A friction detent 58 establishes a releasable connection between member 46, plate 48 and arm 38. In the form of the invention illustrated in Fig. 5, this detent 58 is a transverse pin extending to each side of the supporting arm 38 and having its ends in sliding engagement with the inner or proximal surfaces of member 48 and plate 48. Thus, as the arms are moved around the axis of pins 26 to shift the position of said pins with respect to the longitudinal axis of shaft 22, the cutting edge of blade 28 will be moved toward and from surface 14.

A pointer 52 on each side of arm 38 designates to the operator the thickness of the graft that will be cut when the relative position between pointer 52 and plate 48 is as indicatedby the indicia 54. No inaccurate adjustments will occur when the dermatome is calibrated as illustrated, and the thickness of the skin 'graft may be selected with ease and dispatch. The average skin graft has a thickness of .016" to .028" and the indicla 54 may be such as to define the graft thickness in terms of thousandths-of an inch, if desired. p

Handle 56 on arm 30 opposite to that arm 38 which passes through the slot formed between will have no tendency to 4 knife progressively severs the graft as it is held against surface I4.

The zone of juncture between shaft 28 and one arm 38 may be different from that above described and illustrated in Figs. 1 to 6 inclusive, all to the end that assembly and disassembly may be facilitated. Fig. 7 illustrates the way of journaling one of the pins 26 in its associated arm 38. An opening in arm 38..is great enough in diameter to permit'the passage of shaft 22 longitudinally therethrough. A plug 21 having external screw threads to mate with internal threads in opening 25 is provided with a socket to accommodate pin 26, as illustrated in Fig. 7. When plug 21 is in the position shown, it will effectively, rotatably support shaft 22 but permit its removal, as above set down.

parts against movement and Another manner of mounting an index plate and assembling that member with one of the arms is illustrated in Fig. 8. Index plate 45 is similar to member 46 (Figs. 2, 3 and 4) insofar as it being rigidly affixed to shaft 22 is concerned. A leaf spring 31 mounted upon the inner face of arm 41 is anchored .at one end by a rivet or analogous means 49, while its free end fric-tionally bears against the inner surface of plate 45. A hook 33 having a laterally projected portion 38 s'ervingas a pointer, extends through an opening'in arm 41 to' receive a transverse pin 35 that nests in groove 31 when in the operative position shown in'Fig. 8. As the index plate 45 and thearm 41 are relatively turned, spring 3| will yieldably hold the pointer39 will not only indicate the thickness of graft but/will cooperate with spring 3! in maintaining arm 41 in the adjusted position with cutting blade.28 the desired distance from arcuate face l4. j

From the foregoing it will be observed. that all of the objects above set down are fulfilledand that the dermatome illustrated and descrihedembodies highly advantageous improvements that enhance the value of the instrument shown in my former patent, particularly when abutments 44 are embodied in the structure. These arcuate members '44 are a few thousandths of an inchbeyond the surface l4 when the indexing partsare set at zero and the blade 28 cannot move closer to the shoe 12 to receive injury. This dermatome has the ability of excising the graft without lift.- ing the skin to such an extent as has heretofore been required. The oifsetting of heads 34 on arms 38 and the use of abutments 44 inthe relation illustrated and described, contributes to this advantageous result.

member 46 and plate 48, is utilized by the opera- Precise physical characteristics of the ,dermatome shown in the accompanyingdrawing may be altered without departing from the spirit er the invention or scope of the appended claims. I

Having thus described the invention, what is claimed as new and desired to be secured by Letters Patent is: I v

1. A dermatome comprising a holder having a convex surface rockable over and adapted to progressively lift the skin to be excised; a cutting blade; and a frame for supporting the said cutting blade adjacent to the surfaceof the holder fora cutting movement whereby a graft may be cut progressively as the skin is lifted, said frame comprising spaced abutments for the-blade to limit its movement toward the convex surface of the holder when the blade is assembled with the remaining parts of the dermatome.

2. A dermatome comprising a holder havinga convex surface rockable over and adapted to progressively lift the skin to be excised; a cutting;

blade; and a frame for supporting the said cutting blade adjacent to the surface of the holder for a cutting movement whereby a graft may be cut progressively as the skin is lifted, said frame having an abutment for the blade at each end of the holder respectively, to limit the movement of said blade toward the convex surface of the holder when the blade is assembled with the remaining parts of the dermatome, said abutments having arcuate blade engaging faces concentric with the axis of the convex surface of the holder.

3. A dermatome comprising a holder having a convex surface rockable over and adapted to progressively lift the skin to be excised; a'cutting blade; and a frame for supporting the said cutting blade adjacent to the surface of the holder for a cutting movement whereby a graft may be cut progressively as the skin is lifted, said frame having an abutment for the blade at each end of the holder respectively, to limit the movement of said blade toward the convex surface of the holder when the blade is assembled with the remaining parts of the dermatome, said frame having means for securing the blade in place against the abutments.

4. A dermatome comprising a holder having a convex surface rockable over and adapted to progressively lift the skin to be excised; a cutting blade; and a frame for supporting the said cutting blade adjacent to the surface of the holder for a cutting movement whereby a graft may be cut progressively as the skin is lifted, said frame having an abutment for the blade at each end of the holder respectively, to limit the movement of said blade toward the convex surface of the holder when the blade is assembled with the remaining parts of the dermatome, said frame having means for securing the blade in place against the abutments and being joined to the holder for adjustment toward and from the axis of rotation thereof whereby the cutting blade is shifted toward and from the convex surface as the blade is against the abutments for cutting a graft of desired thickness.

5. A dermatome comprising a holder having a convex surface rockable over and adapted to progressively lift the skin to be excised; a cutting blade; and a frame for supporting the aid cutting blade adjacent to the surface of the holder for a cutting movement whereby a graft may be cut progressively as the skin is lifted, said frame comprising an arm, having an abutment for the cutting edge of the blade, at each end of the holder extending substantially radially from the axis of rotation thereof, a slotted head at the outer end of each arm respectively, and a set screw in each head for clamping the blade in posltion when the same is in the slots, said set screws each having a pressure plug between one end thereof and the blade, formed to prevent transmittal of movement from the respective set screw to the cutting blade.

6. A dermatome comprising a holder having a convex surface rockable over and adapted to progressively lift the skin to be excised; a shaft mounted on the holder at its axis for longitudinal reciprocation and rotation; an eccentrically disposed pin on each end of the shaft and extending longitudinally thereof; a frame having an arm journalling each pin respectively and extending radially from the pins; a cutting blade on the frame adjacent to the convex surface of the holder for movement with the shaft and frame; and adjustable parts for holding the blade predetermined distances from the axis of rotation of the holder at the axis of the shaft whereby grafts of desired thicknesses may be out, said parts comprising a slotted member rigid to the shaft and a detent yieldably arresting relative movement between the member and one of the arms of the frame, said one arm being extended through the slot of the member.

7. A dermatome comprising a holder having a convex surface rockable over and adapted to progressively lift the skin to be excised; a shaft mounted on the holder at its axis for longitudinal reciprocation and rotation; an eccentrically disposed pin on each end of the shaft and extending longitudinally thereof; a frame having an arm journalling each pin respectively and extending radially from the pins; a cutting blade on the frame adjacent to the convex surface of the holder for movement with the shaft and frame; and adjustable parts for holding the blade predetermined distances from the axis of rotation of the holder at the axis of the shaft whereby grafts of desired thicknesses may be cut, said parts comprising a plate rigid to the shaft and projecting radially therefrom to one side of one of the arms of the frame, an index plate on the other side of the said arm, and friction means between the arm and one face of at least one of the plates to yieldably maintain the arm and the plates against relative movement when the cutting blade has been set a desired distance from the convex surface of the holder.

GEORGE J. HOOD.

REFERENCES CITED The following references are of record in the file of this patent:

' UNITED STATES PATENTS Number