BONE IN AMPUTATION STUMPS#{149} Anatomical Laboratory, Western Reserve University

Transcription

1 HEALING BONE IN AMPUTATION STUMPS 353 THE DETAILED CHANGES CHARACTERISTIC OF HEALING BONE IN AMPUTATION STUMPS#{149} By C. G. BARBER, M.D., CLEVELAND, OHIO Anatomical Laboratory, Western Reserve University INTRODUCTION In a previous report on immediate and eventual features of healing in amputated bones1 we have shown some of the general changes occurring in the process of repair. The present paper deals with more detailed changes seen in bones at the site and in the immediate vicinity of amputation. For the most part the specimens used are those of the previous report but, whereas formerly we were occupied with the general features, we now purpose to describe in detail the technical process of repair. SIX The earliest stage of reaction is seen in our specimen W. R. U. 262, male, white, age about forty years, an amputation through the upper third of right tibia and fibula not more than five or six days after operation. The changes seen in this specimen are so slight that they doubtless would have been overlooked had it not been for the erosion of cortical bone demonstrated by the roentgenogram. Indeed this erosion is so slight that only on magnification are definite areas of increased vascularity and accompanying erosion, partially obliterating the saw marks on the cut face, to be seen (Fig. 1-A). Molecular erosion not accompanied by an increased vascularity also results in a rounding of the cut margins (Fig. 1-B). The snailtrack type of molecular erosion, which is so characteristic of commencing sequestrum formation2, is apparent upon the subcutaneous surface, though it is not extensive (Fig. 1-C). ELEVEN The next specimen W. R. U. 864, male, negro, age forty-eight years, is an amputation through the mid-shaft of the right tibia and fibula about eleven days after operation. The cut faces show plainly the saw marks of a recent operation. These markings are being obliterated by a molecular erosion without obviously increased vascularity. The margins also show molecular erosion clearly and present an appearance as of wax somewhat melted by the heat. The erosion is unequally progressive over the cut face; it is most marked in those parts which, owing to thin substance or final operative fracture, have been least injured. They are also quite

2 354 C. G. BARBER FIG. 1-A FIG. 1-B Sawn surface showing partial oblit- Molecular erosion of raw bone edges on eration of saw markings by erosion both sides of accidental adventitious saw and vascularity. cut, subcutaneous surface. FIG. 1 Amputation right tibia. W. It U Male, white, age about 40 years. Amputation upper third 5 or 6 days previously. FIG. 1-C Snail-track type of molecular erosion characteristic of superficial scaling sequestrum formation. vascular. It istruethat inthethick subcutaneous face and ventral margin a chronic inflammatory area is present, which has become involved in the recent vascular activity called forth by the surgical treatment (Figs. 2-A and 2-B). There is internal callus in both bones. In the tibia it is flush with, but in the fibula it is somewhat proximal to the cut face. The callus itself is very porous but intimately united to the cortex. In both bones it is most abundant in those areas where the cortex is thinnest. There is no external callus evident on either tibia or fibula. Increased vascularity with its accompanying erosion is erratically present on the outer surface of the shafts adjacent to the amputation faces. THIRTEEN Left femur W. R. U. 319, male, white, age fifty years, is an amputation through the mid-shaft some thirteen days after operation (Fig. 3). Erosion has obliterated all evidence of saw marks on the cut face. Toward the periphery a type of erosion, obviously accompanied by an increascd vascularity and of a much rougher character than in the preceding specimen, has resulted

3 HEALING BONE IN AMPUTATION STUMPS 355 FIG. 2-A Cut face of bones. Note greatest erosion on fractured posterior area of tibia, next greatest on thinner portions of shafts. There is an area of erosion and vascularity in front on the tibia which is due to the wakening up of a previous inflammatory reaction The internal callus springs from the thinner areas of shaft in each bone. FIG. 2-B Lateral aspect of fibula. Note snail-track characteristic of flaking sequestrum formation. FIG. 2 Amputation right tibia and fibula. W. R. U Male, negro, age 48 years. Amputation through mid-shaft about 11 clays previously. in a marked rounding of the face margins. The same type of erosion also plainly involves the outer surface of the adjacent shaft. Internal callus, though not al)undant, completely surrounds the medullary cavity. It is quite thin except in the area adjacent to the linea aspera, and though inti- - mately Uflite(l to the cancellous tissue, is more l)oou5 and easily differentiated therefrom. A small amount of external callus is seen on the posterior surface of the shaft just medial to the linea aspera. This callus being new is veiv porous in texture and the subjacent cortex is eroded to a greater degree than elsewhere at a similar distance from the cut face. FIFTEEN I)AYS \V. H. U. 1019, male, white, age fifty-eight, is an amputation through the lower third of the right forearm Sonic fifteen (lays after operation. FI(. 3 Amputation left femur. W. II. U Male, white, age 50 years. Amputation middle third about 13 days previously. Note general erosion especially of margins with increased vascularity and internal callus.

4 356 C. G. BARBER anputation severed 1)0th bones helow the marrow cayity afl(l the cancellous tissue of the shafts shows con(lensa t ion greater than in the preceding speciiiiens, 50 that it is not easily (ustinguishable froni the surrounding erode(l cor- Fi;. 4 tex. There are local Amputation right radius and ulna. W. R. U variatiolls in density of Male, white, age 5$ years. #{149} the cancellous tissue of Amputation about 15 days previously through lower third of shaft below marrow cavity. Original cancellous both radius and ulna. tissue completely closes cut end. Erosion of cortex with Molecular erosion commencing waxy transformation of vascularized bone indicating quiescence. has to a moderate degree rounded the cut margins of both bones and irregularly involved the adjacent shafts (Fig. 4). There is a moderate amount of external callus with erosion of subjacent cortical bone on radius and ulna alike. SEVENTEEN Right femur W. R. U. 1585, male, negro, age thirty-one years, is an amputation through the mid-shaft some seventeen days after operation (Fig. 5). The vascularity seen as pits on the cut face, as in preceding specimens, is very marked. Toward the periphery this vascularity is accompamed by erosion and rounding of the margins. There is no internal callus present in the specimen. This absence or minimal development of endosteal callus is of more than ordinary interest, for surrouiu lii ig the marrow cavity are several irregular concentric sheets of thin FIG. hone composed of cancellous tis- Amputation right femur. W. It. U sue. Successive specimens sug- Male negro, age 31 years. Amputation through mid-shaft some 17 gest that this may be the final days previously.. t ransf ormat ion of t lie mt ernal Note general vascularity and erosion especially of margins. The concentric thin lamel- ( allils, forming a framework upon lae of bone in marrow cavity maybe the final which the definitive cai is elabotransformatan of cancellous tissue upon which the definitive cap is elaborated. rate(l.

5 HEALING BONE IN AMPUTATION STUMPS 357 There is a large mass of external callus on the posterior surface of the shaft medial to the linea aspera. It is somewhat proximal to the cut end, very porous in texture, with definite erosion of cortical bone beneath. The vascular apertures both on the surface of the shaft and on the cut end are much larger than in previous specimens. In places they are narrowed by an exuberance of recent bone of wax-like texture. This phenomenon is more pronounced in specimens described later. SEVERAL WEEKS Right femur, amputated through the mid-shaft several weeks previously (Fig. 6), W. H. U. 952, was obtained from a male, white, age forty years. Erosion has rounded the outer edge of the cut face which is of much closer texture than that of the preceding specimen and indicates a further stage in the healing process. The margin of the medullary canal is for the most part sharply angular with a tendency to curl toward the center of the marrow cavity. This is most marked at the anterior margin, where it has extended some little distance across the open end, spreading itself over the new cancellous endosteal callus as over a framework. As in the two preceding specimens, there is a small remnant of external callus on the posterior surface of the shaft, which likewise shows a much closer texture, illustrating the approach of a quiescent period such as presents itself in the example next upon our list. Fu;. 6 Amputation right femur. W. It. U Male, white. age 40 years. Amputation through middle of shaft several weeks previously. Outer edge of cut face eroded. Closer texture of cut face indicates a further stage in healing. Extension of endosteal callus to form partial cap. Fa;.7 Amputation left femur. W. IL U Male, white, age 71 years. Old amputation through lower shaft. Fenestrated cap of condensed cancelbus bone, with periosteal osteophyte of condensed texture.

6 358 C. G. BARBER ULTIMATE APPEARANCE Left femur W. R. U. 1519, male, white, age seventy-one years, is an old amputation through the mid-shaft. The margins of the cut face are rounded (Fig. 7). The texture of the imperfect cap is even more condensed and lava-like in appearance than in the preceding specimen. The cap of endosteal callus is most nearly complete posteriorly, where its texture is also most condensed and shows greatest progress in healing. The medullary canal is indeed now more than half closed by an irregularly fene- - strated cap, the inner parts of which are composed of a mere bony meshwork. A periosteal osteophyte of eondensed texture appears medial to the linea aspera 111 the site where cxternal callus has been noted on three femoral amputations previously described. The final stage seen in our specinien W. H. I,J. 1217, male, white, age fifty-nine years, is again an amputation of long stan(ling through the upper shaft of the right femur. rili)e margins of the cut face have been FIG. 8 rounded and the marrow cavity has Amputation right femur. W. R. U. been completely closed by a cap, Male, white, age 59 years. erratic in thickness translucent in Old amputation through upper shaft. Ideal technical result with completely quies- places, and everywhere composed of cent though irregularly osteoporotic cap quiescent waxy textured bone (Fig. and negligible osteophytes. Note the.. waxy texture of the quiescent bone. 8). There is hppmg with some osteophytic development in the usual site, medial to the linea aspera and also on the lateral margin. SUMMARY In the foregoing pages we have presented specimens illustrating in detail the several stages of healing bone in amputation stumps. Within five or six days from the date of operation (W. R. U. 262) the cut surface is rarefied by increased vascularity so fine that, though it is obvious in the roentgenogram, it cannot be seen on the specimen except under magnification. This erosion gradually obliterates the saw cuts and rounds off the margins of the cut face. By the lapse of eleven days after operation (W. H. U. 864) the erosion, unequally progressive and still permitting evidence of the saw cuts, is plainly most active in those areas of the cut shaft which are thinnest and least injured. After thirteen days (WI. R. U. 319) the saw cuts may be entirely obliterated and callus, both periosteal and endosteal, well developed.

7 HEALING BONE IN AMPUTATION STUMPS 359 If the amputation has taken place through cancellous tissue and not through the marrow cavity, the lapse of fifteen days (W. R. U. 1019) is enough to permit fair healing with even the commencing appearance of waxy textured bone on the face of the stump. But if the marrow cavity be opened, seventeen days later the canal is still quite patent, though narrowed somewhat by the development of concentric rings from the endosteal callus (W. R. U. 1585). After several weeks the endosteal callus has formed an imperfect cap for the medullary cavity and the vascular channels on the eroded cut face are narrowed (W. R. U. 952). This is soon followed by the closure of the vascular channels and by a wax-like transformation of the texture of the new bone (W. R. U. 1519, W. R. U. 1217). CONCLUSIONS Early vascularity with erosion are characteristic of the first stage in bone healing after amputation. The production of periosteal and endosteal callus is minimal and definitive callus is almost lacking. Nevertheless, capping of the medullary cavity is more or less completely attained, after which the amputated face becomes quiescent. The vascular channels fill in and become obliterated by a quiescent bone of waxy texture. The afterresults of amputation are therefore precisely similar in kind though not in degree to those seen after fracture. REFERENCES CITED I. BARBER, C. G.: Immediate and Eventual Features of Healing in Amputated Bones. Ann. Surg., XC, 985, TODD, T. W. AND ILER, D. H.: The Phenomena of Early Stages in Bone Repair. Ann. Surg., LXXXVI, 715, 1927.