On the basis of additional experience, the condition which one of us (H. L. J.) described in 1935 under the name of osteoid-osteoma has again been considered. Including the five cases originally described, our total experience with the condition now covers thirty-three cases. In the present paper, we have, of course, drawn on this total experience for the statistics and the general sections on the clinical, roentgenographic, pathological, and therapeutic findings. In addition, this paper records details on eight cases (not including any already described in the original paper) which have been selected to convey a well-rounded picture of the condition as one encounters it in individual instances.
Our thesis is that osteoid-osteoma constitutes a lesion sui generis and specifically is a distinctive benign tumor appearing in bones. It is always a small lesion affecting a single bone. It may develop in the spongiosa or in the cortex of the affected bone, and it stands out from the surrounding osseous tissue as a sharply delimited nidus. The latter is usually composed of osteoid and more or less calcified atypical new bone, which can be seen to have developed out of a rather vascular osteogenic connective tissue. From the findings in our series of cases, an osteoid-osteoma seems to run the following histogenetic course: It appears to pass from (1) an initial stage, in which actively proliferating and compacted osteoblasts may be prominent, through (2) an intermediate phase, in which osteoid in various stages of calcification is conspicuous, to (3) the mature stage, in which the prominent feature of the lesion is the presence of densified trabeculae of highly calcified atypical bone. When an osteoid-osteoma develops in spongiosa, a narrow or even fairly wide zone of the surrounding spongy osseous tissue usually becomes densified and sclerotic; if an osteoid-osteoma develops in cortex, the latter, too, tends to become thickened, mainly through periosteal new-bone deposition. In fact, if the lesion develops in the cortex of a long bone, as it not infrequently does, the reactive cortical thickeining may be very striking.
Thus, in interpreting the roentgenographic picture in a case of osteoid-osteoma, one must remember that this picture has two aspects,-the manifestation of the osteoid-osteoma proper and that of the reaction which it has incited in the surrounding tissue. The osteoid-osteoma proper is usually indicated roentgenographically by a relatively radiolucent or rarefied area, although, if it has become substantially ossified, it may appear as a relatively radiopaque nidus. In the cortex of a long bone, one may have difficulty in distinguishing the osteoid-osteoma shadow if the reactive cortical thickening is considerable or if the lesion has become ossified, since its shadow may be dominated by that of the thickened cortex. In any event, because the roentgenographic picture has these two aspects, a case of osteoid-osteoma in a spongy-bone area is commonly mislabeled chronic osteomyelitis with a bone abscess or with an annular sequestrum, the label depending upon the extent to which the osteoid-osteoma has undergone ossification. A case of osteoid-osteoma in the shaft of a long bone is commonly mislabeled sclerosing non-suppurative osteomyelitis of Garre or intracortical-bone abscess, the latter diagnosis tending to be made especially when the rarefaction shadow in the cortex is very distinct and the cortical thickening is not very pronounced.
Clinically, it is striking that the disorder has a predilection for adolescents and young adults, principally between the ages of ten and twenty-five. The presenting symptom is localized pain, usually of at least several months' duration, which may be persistent and severe enough to wake the patient at night. It should be emphasized that the clinical findings do not point to an infectious inflammatory origin for the disorder, although, in the past, surgeons, like roentgenologists, have usually interpreted the combined clinical and roentgenographic pictures in these cases as indicating such an origin. As to treatment, surgical excision of the osteoid-osteoma proper with some of the surrounding bone was the procedure used in our cases. It resulted in clinical cure with prompt and often dramatic relief of distressing pain. During our experience with the lesion-an experience now covering seven years-no recurrence has been noted in any of our cases.
(C) 1940 All Rights Reserved.The Journal of Bone and Joint Surgery, Inc.