months or years. <Callout type="important" title="Important">If the enlargement of the bone is attended with suppuration, and on opening the abscess, or on probing the sinus left by such abscess, hard smooth, bare bone is felt, necrosis has occurred.</Callout> A seques- trum is shown in a skiagram as a shadow denser than normal bone. Inflammatory molecular dismtegration or rare- faction of bone is often spoken of as caries or ulceration of bone. In the spine it is recogmzed by the occur- rence of angular curvature, elsewhere by the exist- ence of a cavity where none should be; hue granules of dying bone at the deep end of a sinus may often be felt. The rarefaction of the bone and its exact extent are best learnt from a good skia|iam^ growing or stationary tumour, noticed first in early life, hard in consistence, opaque to X-rays, and attached to the diaphysis at or near an epiphysis, is an exostosis. Such a tumour is usually .^dJculated, but may be sessile. It may be smgle or multiple, rounded or lobulated. It may have a bursa developed over it. Exostosis commences as a cartilaginous outgrowth, and so long as the gi-owth nSiCa layer^of cartilage will be lo.^^ ojertU bone but when the bone is completed the whole exostosis ossifies and growth ceases. In rare cases the tumour continues to grow after the ossification of the Xcted bone is completed; such tumours hav nu^h cartilage m their composition and are bable o become sarcomatous. Exostoses are most often met wTth at the lower end of the humerus and femur Zl It the upper end of the ^^-'J^f^f^^^ the great toe and on the skull, f '^^'f/ Jj^malb at the epiphysial line, they may by tlie glo^^tll Periosteal surcoma iil Icimir. <Callout type="risk" title="Risk">Periosteal sarcomas can grow to great size and through the stretched skin enlarged veins may be seen.</Callout> Its consistence varies; part may chondrify, and ossification, spreading from the surface of the bone, plainly shown by X-rays, is common. The affected bone is usually eroded, and the tumour may penetrate into, and luxuriate in, the medulla ; <Callout type="warning" title="Warning">Pul- taueous fracture is liable to occur.</Callout> Very occasion- ally, a periosteal sarcoma shows no tendency to ensheatlie the bone, but forms a globular outgrowth from the bone. A swelling on a flat bone — e.g. the scapula or the innominate bone — which rapidly extends along its surface and quickly appears on its opposite surface, firm in consistence, smooth or slightly lobed in out- line, is a periosteal sarcoma. The rapidity of growth and the great size attained are very striking features of these tumours in their later stages. It is doubtful if pulsation is ever observed in this form of the disease. A steadily progressing enlargement of a long bone, shown by a slriagram to be due to a swelhng within the bone which has replaced the cancellous bone and expanded the outer compact bone, is either a myeloma, central sarcoma, or osteitis fibrosa, with cyst-formation. If the skiagram shows that the swelling is towards the end of the bone, very transparent to X-rays, the shadow being without mottling or stria- tion, more or less globular in form, and the shell of bone, though thin, is unbroken, it is a serous cyst, or the result of osteitis flbrosa. (Plate vii.) In this disease the swelling develops slowly and may be arrested. Spontaneous fracture may be the first evidence of the condition. The humerus and the femur are the bones most commonly affected by this disease. If the central swelling of the bone mvolves the epiphysis largely, stretches and flattens the adjacent articular cartilage, fungates through the thin layer of compact bone, but does not grow with great rapidity, it is a myeloma. (Plate vin.) In the skiagram this tumour gives a shadow m wluich faint mottlings or striatioiis are seen. If tlie cent,rul tumour differs from the above by Osteitis fibrosa of lemi.r, nitli cyst-lormation. Plate VII. Myeloma of libulii. PLATE VIII. XXIV] SECONDARY CARCINOMA OF BONE 327 iuvolving the diapliysis more extensively, and by more rapid growth, greater destruction of bone, and earlier spontaneous fracture, it is a central sar- coma. Egg-shell crackling of the thinned expanded bone and pulsation of the tumour may be felt both in myeloma and in central sarcoma. A moderate enlargement of the diaphysis of a long bone with moderate expansion of its medullary cavity, and the replacement of the medulla by a tissue which gives a mottled shadow in the skiagram, may be an endo- thelioma. This rare tumour affects the diaphysis rather than the epiphysis of a bone, tends to spread far along the interior of the bone, and does not absorb bone so rapidly or so extensively as does a central sarcoma. A swelling in a bone of a patient who has or has had carcinoma elsewhere — particularly in the breast or thyroid gland — is probably a secondary carcinoma of bone. (Plate ix.) Its destructive^ effects upon the bone may be evidenced by the occurrence of spon- taneous fracture, or the skiagram may show the replacement of bone by a less opaque, slightly mottled, and irregular substance. Such a growth is usually painful, but the occurrence of a spontaneous fracture may be the first symptom noticed. A smooth, more or less globular enlargement of a bone, shown by a skiagram to be due to a sub- stance transparent to X-rays, which has rarefied and expanded the bone, may be a hydatid cyst. If there is excess of the eosinophile cells of the blood, and if the patient has or has had hydatid disease else- where, the diagnosis is confirmed. The diagnosis is more readily made if the patient has lived in Aus- tralia, northern New Zealand, or Iceland, where hy- datid disease is common. The disease may be only discovered on the occurrence of spontaneous fracture. 328 SURGICAL DIAGNOSIS U is met -wit-h iu flat bones, as well as in eifcluT tlie shaft or the iomt-ends of long boues. A soft or elastic, finely lobulated tumour with a limited attachment to a bone is a lipoma. These tumours are always congenital, and the diagnosis is more readily made if this fact is brought out in the history. If a tumour in connexion with the shaft of a bone grows very slowly, assumes a smooth globular outline, and is firm and painless, a fibroma may be diagnosed. In general features it will most nearly resemble enchondroma, from which it can only be distinguished by its position : ossifymg enchondro- mata start from the junction of epiphysis with diaphysis, and central enchondromata affect the long bones of the hand. From sarcoma it will be differ- entiated by its more chronic course, its very slow growth or even stationary character, and the absence of fracture or pulsation. Fibroma is a very rare tumour of bone, except in the form of fibrous epulis. / Plate ix. I a i c 1 c t d t s n t\
Key Takeaways
- Necrosis and abscesses can indicate bone infections.
- Exostoses are benign bony growths that usually occur at the ends of bones.
- Periosteal sarcomas can grow rapidly and may cause fractures.
- Myelomas, central sarcomas, and osteitis fibrosa can be distinguished by their X-ray appearances.
- Hydatid cysts are a risk in regions with endemic hydatid disease.
Practical Tips
- Always consider the patient's history when diagnosing bone swellings to rule out congenital conditions like lipomas.
- Use X-rays for detailed diagnosis of bone tumors, as they can reveal subtle changes not visible on physical examination alone.
- Be cautious with periosteal sarcomas, as they may cause spontaneous fractures and require urgent attention.
Warnings & Risks
- Periosteal sarcomas are a significant risk due to their potential for rapid growth and causing fractures.
- Exostoses can be mistaken for more serious conditions like sarcomas if not properly diagnosed.
- Fibromas, while rare, should still be considered in the differential diagnosis of bone swellings.
Modern Application
While many of these techniques are rooted in historical practices, the principles of diagnosing and managing bone tumors remain relevant. Modern imaging technologies like MRI can provide additional insights beyond X-rays, but the importance of a thorough history and physical examination remains unchanged. Understanding these conditions is crucial for effective triage and emergency response in survival scenarios.
Frequently Asked Questions
Q: What are exostoses, and how do they differ from sarcomas?
Exostoses are benign bony growths that usually occur at the ends of bones. They can be mistaken for more serious conditions like sarcomas if not properly diagnosed, as both may appear similar on physical examination.
Q: How can periosteal sarcomas be identified?
Periosteal sarcomas are identified by their rapid growth and the presence of enlarged veins through the stretched skin. They often form a globular outgrowth from the bone, and may cause spontaneous fractures due to their aggressive nature.
Q: What is osteitis fibrosa, and how does it differ from myeloma?
Osteitis fibrosa involves the replacement of bone by a tissue that gives a mottled shadow in X-rays. It differs from myeloma, which shows faint mottlings or striations on X-rays due to its slower growth and less extensive destruction of bone.