HISTOLOGICAL STRUCTURE OF HUMAN FLUOROTIC BONES

Transcription

1 HISTOLOGICAL STRUCTURE OF HUMAN FLUOROTIC BONES INDAR JIT, ROHTAK, INDIA L. S. CHAWLA and P. N. CHHUTFANI, CHANDIGARH, INDIA From the Department of Anatomy, Medical College, Rohtak, and the Department of Medicine, Postgraduate Institute of Medical Education and Research, Chandigarh Pioneer work on clinical fluorosis in the Punjab has been done by Singh and his associates (Singh, Jolly and Bansal 1961 ; Singh, Dass, Hayreh and Jolly l962a; Singh, Jolly, Devi, Bansal and Singh l962b; Singh, Jolly, Bansal and Mathur 1963). In patients with fluorosis they found the fluorine content of blood and urine to be raised. They took an open bone biopsy from tibiae of the fluorotic patients and described the histopathological picture of the bone as showing disordered lamellae and an enlarged poorly formed Haversian system. They described the same picture in the first two papers, but in 1963 they added that in the spongy bone areas of osteoid tissue could be seen among well formed trabeculae and that some irregular deposits of osteoid tissue extended into the attached muscle. An identical histopathological description was given by Singh (1967) in a monograph on endemic fluorosis. Weatherell and Weidmann (1959) induced experimental fluorosis in the bones of rabbits and one sheep by allowing the rabbits to drink water containing 500 parts per million of fluorine as sodium fluoride for three days to twenty-one weeks and by administering 10 milligrams of fluorine as sodium fluoride to the sheep daily for one month. The bones of the animals showed fluorotic exostoses which consisted of coarse bundles of woven bone with open trabecular network and having a small degree of irregular replacement by lamellar structure, the lamellae being haphazard and showing unusual patterns. They also demonstrated wide seams of osteoid tissue in undecalcified sections of exostotic bone from the metatarsal bones of the fluorotic sheep. As the only reference in the literature to the histopathological appearance of the human fluorotic bone is found in the papers of Singh et a!. (1961, l962a, 1963), it was considered necessary to repeat the study in the material available to us. MATERIAL AND METHODS The material consisted of two skeletons from fluorotic patients aged forty and forty-five years. Both showed well marked exostoses at the sites of attachment of muscles and ligaments, indicating advanced fluorosis. Ground and usually wax-embedded sections were prepared from exostoses which included those present at the site of attachment of tibialis anterior and soleus to the tibia, gluteus medius to the ilium, calcaneal spurs, lower part of the ossified tendo calcaneus and linea aspera. Transverse sections were also cut from 1) the femora below the level of the lesser trochanter, and above the level of the adductor tubercle ; 2) the tibia at the level of the tibial tuberosity ; and 3) the parietal bone near its lower border. Wax-embedded sections were cut at 1 5 microns after pieces of the bones and exostoses had been decalcified in various decalcifying agents including 5 per cent trichioracetic acid and those recommended by Brain (l966)-lo per cent ethylene-diamine-tetra-acetate, N nitric acid and 4N formic acid. Staining methods included haematoxylin and eosin, toluidine blue, Von Kossa, Masson s trichrome, picrothionin (Schmorl 1934), 1 per cent basic fuchsin in 30 per cent alcohol, and 0 1 per cent alizarin red S (Frost 1959). 366 THE JOURNAL OF BONE AND JOINT SURGERY

2 HISTOLOGICAL STRUCTURE OF HUMAN FLUOROTIC BONES 367 -B FIG. 1 Macrophotograph of a ground section of fluorotic tibia from the region of the soleal line. A part of the bony corticular arch with a well marked exostosis is seen. Note the enlarged Haversian canals: 1) towards the medullary cavity (uppermost in picture); 2) at the base; and 3) at the apex of the exostosis. (Unstained, x 10.) A special section was prepared from a fluorotic tibia. A transverse section two to three millimetres thick of the bone containing marked exostosis was cut from the second skeleton with a fine saw. Part of the bony corticular arch, to which exostoses were attached on the outer side and medullary cavity seen on the inner side, was retained, made into ground section of about 50 micra thickness, photographed (Fig. 1) and examined microscopically. Photomicrographs were then obtained from three different areas of the section as shown in Figure 1 : 1) from the middle of the cortex at A ; 2) from about the middle of exostoses at B; and 3) from the peripheral part of the exostosis at C. VOL. 52 B, NO. 2, MAY 1970

3 368 I. JIT, L. S. CHAWLA AND P. N. CHHUTTANI OBSERVATIONS AND DISCUSSION A magnified photographic view of the entire special ground section (Fig. 1) shows areas of enlarged Haversian canals (reabsorption tunnels). These areas are seen particularly: 1) in FIG. 3 FIG. 4 Figures 2-4--Photomicrographs of areas A, B and C in Figure 1. Note the presence of well formed concentric Iamellae in the Haversian systems both in the cortex (Fig. 2) and in the exostosis (Figs. 3 and 4). (Unstained, 72.) the cortex near the medullary cavity; 2) at the base; and 3) at the apex of the exostosis. The remaining areas of the cortex and exostosis show Haversian canals of normal size as seen in sections obtained from young tibiae. THE JOURNAL OF BONE AND JOINT SURGERY

4 HISTOLOGICAL STRUCTURE OF HUMAN FLUOROTIC BONES 369 Microscopic examination of the ground section confirms the appearance described above, and further shows a large number of areas containing well developed concentric lamellae with rounded Haversian canals conforming to the appearance described for newly forming Haversian systems (Ham 1965). Such areas are seen both in the cortex and in the exostoses FIG. 5 Photomicrograph of ground section from the shaft of a fluorotic tibia. Well formed Haversian systems are seen, similar to those of normal bone. (Unstained, x 84.) FIG. 6 Photomicrograph of a decalcified section from the shaft of a fluorotic femur. Although some of the Haversian canals are enlarged, the lamellar arrangement in the Haversian systems is normal and shows no signs of disorganisation. (Unstained ; phase contrast, x 84.) (Figs. 2 to 4). The number and sizes of the reabsorption tunnels do not appear to be more than described by Ham in the bones of a child or an old person where a rapid turnover of the bone is taking place. Areas of osteoid tissues are not visible in sections stained by techniques of Von Kossa, alizarin red 5, and basic fuchsin (Frost 1959). Disordered lamellae or poorly formed Haversian systems as described by Singh et a!. (1961, l962a) cannot be seen. VOL. 52 B, NO. 2, MAY 1970

5 370 I. ut, L. S. CHAWLA AND P. N. CHHUTFANI Microscopic examination of a large number of ground and decalcified sections from different exostoses and from femora, tibiae and parietal bone of fluorotic skeletons showed similar appearances (Figs. 5 and 6). Depending upon the density of an exostosis, the size of the reabsorption tunnels may be large. However, the canaliculi and lacunae in the Haversian system are normal. Histological features seen in experimental animals with induced fluorosis (Weatherell and Weidmann 1959) are quite different from those seen in human fluorotic bones. Woven bone is not visible even in the exostosis. Staining of sections by Von Kossa method does not exhibit any osteoid seams. Staining with toluidine blue also fails to show metachromatic staining of the second lamella, described by Weatherell and Weidmann (1959). SUMMARY 1. Fluorotic bones and exostoses obtained from the skeletons of two subjects with advanced fluorosis have been examined microscopically. 2. The cortical bone showed normal, regular Haversian systems with normal canaliculi and lacunae. The exostoses also exhibited normal, regular Haversian systems but at places the reabsorption tunnels were large. 3. Special stains failed to show osteoid tissue either in the fluorotic bones or in their exostoses. REFERENCES BRAIN, E. B. (1966): The Preparation of Decalcified Sections. Springfield, Illinois : Charles C. Thomas. FROST, H. M. (1959): Staining of Fresh, Undecalcified, Thin Bone Sections. Stain Technology, 34, 135. HAM, A. W. (1965): Histology. Fifth edition, p Philadelphia: Lippincott ; London: Pitman Medical Publishing Co. Ltd. SCHMORL, G. (1934): Diepathologisch-histologischen Untersuchungsmethoden. Sixteenth edition. Berlin : Vogel. SINGH, A. (1967): Endemic Fluorosis (Epidemiology and Clinical Aspects). Indian CoundiofMedical Research Special Report, No. 57, 1-9. SINGH, A., D.ss, R., HAYREH, S. S., and JOLLY, S. S. (1962a): Skeletal Changes in Endemic Fluorosis. Journal of Bone and Joint Surgery, 44-B, 806. SINGH, A., JOLLY, S. S., and BANSAL, B. C. (1961): Skeletal Fluorosis and its Neurological Complications. Lancet, i, 197. SINGH, A., JOLLY, S. S., BANSAL, B. C., and MATHUR, C. C. (1963): Endemic Fluorosis: Epidemiological, Clinical and Biochemical Study of Chronic Fluorine Intoxication in Punjab (India). Medicine, 42, 229. SINGH, A., JOLLY, S. S., DEw, P., BANSAL, B. C., and SINGH, S. S. (196Th): Endemic Fluorosis. (An Epidemiological, Biochemical and Clinical Study in the Bhatinda District of Panjab.) Indian Journal of Medical Research, 50, 387. WEATHERELL, J. A., and WEIDMANN, S. M. (1959): The Skeletal Changes of Chronic Experimental Fluorosis. Journal ofpathology and Bacteriology, 78, 233. THE JOURNAL OF BONE AND JOINT SURGERY