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Ski Injuries
1388
inclined to follow the example of the pathologists. Their case, however, is somewhat different; for they are physicians in direct contact with patients, and their secession from the Royal College of Physicians would have a far more disturbing effect on medicine than the establishment of an independent College of Pathologists. Is is much to be hoped, therefore, that they can be given full scope within the college, though this will raise administrative problems of the same kind, though not perhaps as inconvenient, as would have arisen from incorporation of the pathologists in a separate faculty. Representative and administrative machinery which was designed for small numbers in the remote past may need considerable alterations if a single body, with or without component faculties, has to represent several thousand people. Biologically, cell division is an inevitable accompaniment of growth; and to that extent the fissiparous tendency we have been discussing is no doubt a natural process. But if there are to be numerous independent or semi-independent bodies representing different specialties, ought there not to be some coordination between them? After all, the multicellular organism is more efficient than the unicellular-because the specialisation of its parts is balanced by integration. Today medicine in this country often seems like an incoherent group of unicellular organisms rather than a coordinated whole. Colleges, faculties, and Associations often cover the same ground as the specialist committees of the B.M.A., while a kind of cross-representation is provided by the Regional Hospitals’ Consultants and Specialists Association, the Central Consultants and Specialists Committee, and the Joint Consultants Committee ; and the Central Health Services Council has its own brood of specialist committees. From time to time an Academy of Medicine is proposed as a solution; but one may question whether the interchange of knowledge between the specialties could be carried out better than it is at present by medical societies, journals, and other agencies. Nor would an Academy readily impose coordination on all these diverse groups. Perhaps, like the British Commonwealth, we can only watch the new nations achieving independence, and hope for the best. Meanwhile, we may hope that the Royal College of Physicians, remaining primus inter pares, will not allow these secessions to trouble it unduly. Continuing to admit to its fellowship distinguished representatives of all medical specialties, including pathology, it can maintain and strengthen its who
are
unique position. Ski
Injuries
of the most popular of all participation sports, even in such lowland countries as Great Britain; and the suntanned tyro with a leg in plaster is now a common sight in our winter scene. The incidence of injury is higher in skiing than in most sports. An accident-rate of 0-5-1% per day is reported from Europe and North America1 2; the skier must SKIING is fast
1. 2.
becoming
one
Moritz, J. R. Amer. J. Surg. 1959, 98, 493. Earle, A. S., Moritz, J. R., Saviers, G. B., Ball, J. D. J. Amer. med. Ass. 1962, 180, 285.
therefore expect an injury sufficiently severe to take him to a doctor in every 100-200 days of skiing. Injuries are commoner in the novice; but, because of his slower speed, they are usually less severe than those in the experienced skier. The features of skiing which make it so dangerous include high speeds, the mechanical leverage of the skis, and the effects of cold and fatigue on muscular function. ERSKINE3 remarked that the momentum of a 150 lb. man travelling at 30 m.p.h. is 6600 ft. lb. per second. If the tip of his ski then catches an object and applies a twisting force, a moment is created at the ankle, which acts as the fulcrum, and the injuring force is the momentum multiplied by the distance from the boot to ski tip. The better the ankle is supported by the boot, the more likely are the tibia and fibula to fracture immediately above the boot; the stronger the bones the more likely is the force to be transmitted to ligaments, which may then rupture. When a great force is suddenly applied, as in falls at speed, bone, being rigid, will fracture; whereas if the force is gradually applied, as in the slower falls of the novice, the bone transmits the force to the ligaments of the knee which will rupture. According to WILLIAMS,4 novices sustain a higher proportion of knee and ankle strains, while practised skiers, in the series of BAUMGARTNER,Ssustained a higher proportion of lower-limb fractures. Lower-limb injuries almost always result from rotation strains due to striking an obstacle with the ski tip, " catching an outside edge " when turning, or simply crossing skis on a ski-tow. Forward flexion injuries, which are less common, also result in serious ankle injuries, one of the most disabling of which is a ruptured tendo achillis. A direct forward fall accompanied by divergence of the ski tips results in a spectacular fall picturesquely described " as an egg-beater ". In this fall, as in many in which release bindings free the ski from rigid contact with the boot, the projecting metal edges of skis may cause lacerations. Injuries to the upper limb are much less common; lateral falls on to hard snow or ice may fracture the tuberosity of the humerus, while falls on to an outstretched hand which holds a ski stick may result in a metacarpal fracture. Dislocation of the shoulderone of the more usual upper-limb injuries-often results from a fall at speed when the abducted arm is caught in soft snow as the body continues descending the slope.
Prevention of skiing accidents has attracted much interest. Release bindings, euphemistically called " safety bindings ", have been developed to release the boots from the ski when sharp twisting or flexion strains occur. Release bindings have become increasingly popular in the past ten years, and most skiers now use at least the lateral release pattern. But the number of different release bindings6 is an indication that the perfect " safety " binding has not been developed ; and it is important to obtain expert advice on the 3. Erskine, L. A. Amer. J. Surg. 1959, 97, 667. 4. Williams, J. A. Lancet, 1956, i, 96. 5. Baumgartner, W. Munch, med. Wschr. 1960, 102, 2220. 6. See Young, N. J. E. British Ski Year Book, 1961. Ski Club of Great Britain.
1389
lend themselves to the kind of graphic representation in which teachers of biochemistry delight. Mapped out, et al.2 find that since the introduction of release bindings there has been no decline in the incidence of ski injuries their interrelations tend to group themselves into clusin Sun Valley, Idaho. HowKINS,7 on the other hand, ters, each cluster centred around a more or less arbifound that the wearing of release bindings had decreased trarily chosen molecular fragment, and each fragment both the incidence and severity of injury in insured linked more or less closely to the lipid or carbohydrate British skiers. pathway. Among these focal fragments, structurally the loss of and are all confidence, Inexperience, fatigue simplest but metabolically one of the most difficult to important factors predisposing to skiing accidents. keep track of is the one-carbon unit. It exists at three There are no short cuts to experience, but good tuition levels of oxidation-methyl (CH3-), hydroxy-methyl ensures that it is acquired as painlessly as possible and (CH20H-), and formate (O=CH-)-and, in comis put to the best advantage. Loss of confidence is bination with nitrogen, as the important formimino closely related to inexperience and fatigue, and often radicle (NH=CH-). There is probably no one-carbonresults from unexpected changes in snow conditions. unit " pool " in the body in the sense that there is an Loss of confidence following injury seems important in ammonia or acetyl pool; nor do we now believe that the " predisposing to further injury; for KRAUS 8 reported organism depends on a steady supply of labile " that 40% of the knee injuries in his large series were methyl-group donors to meet its one-carbon-fragment re-injuries. Gradual reablement after injury is there- requirements. Compounds used to be tested for their fore important, and skiers would be wise to rejoin ski ability to provide such groups by observing whether they classes of a lower standard than that which they had could replace the classical methyl-group donor, methioreached at the time of injury. Accidents are commonest nine, in the homocysteine-supplemented diet of rats; towards the end of a day’s skiing 1-3 9-a feature associ- but most of these diets probably chanced to be deficient ated with changing snow conditions and fatigue. The not only in methyl groups but also in vitamin B12 and onset of fatigue, which is perhaps the biggest single folic acid. When these vitamins are supplied the adult factor predisposing to injury, can be delayed by (though probably not the newborn) organism can synthemeans of preparation, including pre-ski exercises, aimed sise methyl. and other one-carbon fragments from many at physical fitness. But for most participants, skiing is sources and transfer them enzymatically from one coma sensuous pleasure rather than an athletic pursuit; and pound to another. however much they are exhorted to sway on half-bent The role of desoxyribosenucleic acid (D.N.A.) and of knees for a month before their holiday or to spurn ski- ribonucleic acid (R.N.A.) in cellular multiplication is now lifts for the first five days, the majority will make their well established. The biochemical individuality of these first journey of the year on snow downhill from the top giant molecules-generally regarded as the repositories of a ski-lift using untrained muscles. These people and transmitters of genetic information-depends on the especially should learn when to stop; for one of the sequence and disposition of subunits derived from the greatest temptations in skiing is to take " just one more purine and pyrimidine nucleus; and experimental evidence suggests that in most cells the basic ring structure run down ". Perhaps the greatest advantage of spurning ski-lifts is that this deters the tired from taking another of these substances is synthesised rather than abstracted run when their bodies have had enough. ready-made from extracellular sources. Our understanding of how this is accomplished is very incomplete; but FIGLU there is little doubt that the shedding, incorporation, IGNORANCE of the second law of thermodynamics has amination, and transamination of one-carbon units are been publicised as a symptom of the exclusive literary essential steps in the process. These interchange and culture. Latin scholars may find the outrages committed transfer mechanisms are catalysed by enzymes; and to scientists on the classical tongues no less lamentable. some of these enzymes vitamin B2, folic acid, or both act by " FIGLU " cuts short the budding Virgilian hexameter, as coenzymes or intermediate carriers. Of the two vitaformiminoglutamic acid; and in this form it is beginning mins the sites of action of folic acid have been rather more to be used in medical parlance. Its interest to doctors clearly defined: it is known, for example, that after stepstems from the discovery that in folic-acid deficiency it wise reduction to tetrahydrofolic acid it acts as the transit replaces glutamic acid as the urinary end-product of stage for a hydroxymethyl group between deoxyuridylic histidine metabolism.1Q-13 This observation, first made and thymidylic acids, close precursors of thymine.14-16s on rats only nine years ago, has already inspired a numTHORELL and others who have studied the D.N.A. and ber of ingenious and useful diagnostic tests; and it has R.N.A. content of megaloblasts at successive stages of stimulated fresh interest in the biochemical ramifications development found that, while the quantity of D.N.A. in of the megaloblastic ansemias. the nucleus tends to remain unchanged, large amounts The turnover of aminoacids, purines, and pyrimidines Of R.N.A. accumulate in the cytoplasmJ7 18 This imbalin the body (unlike fat and carbohydrate metabolism) do ance could reflect the diminished capacity of these cells 7. Howkins, J. Brit. med. J. 1958, i, 1006. to synthesise D.N.A. and their consequent tendency to 8. H. Amer. med. Ass. 1414.
selection, fitting, and adjustment of bindings. EARLE
Kraus, J. 1959, 169, Staples, O. S. New Engl. J. Med. 1961, 264, 552. Silverman, M., Bakerman, H., Daft, F. S. Fed. Proc. 1951, 10, 247. Luhby, A. L., Cooperman, J. M., Teller, D. N. Proc. Soc. exp. Biol., N.Y. 1959, 101, 350. 12. Brohquist, H. P., Luhby, A. L. Fed. Proc. 1957, 16, 159. 13. Spray, G. H., Witts, L. J. Lancet, 1959, ii, 702. 9. 10. 11.
not
Girdwood, R. H. Brit. med. Bull. 1959, 15, 14. Friedkin, M., Kronberg, A. in The Chemical Basis of Heredity (edited by W. D. McElroy and D. Glass). Baltimore, 1957. 16. Knowles, J. P., Prankerd, T. A. J., Westall, R. G. Lancet, 1960, ii, 374. 17. Thorell, B. Acta med. scand. 1947, suppl. 200. 18. Riensner, E. H., West, R. Proc. Soc. exp. Biol. N.Y. 1949, 71, 651. 14. 15.
inclined to follow the example of the pathologists. Their case, however, is somewhat different; for they are physicians in direct contact with patients, and their secession from the Royal College of Physicians would have a far more disturbing effect on medicine than the establishment of an independent College of Pathologists. Is is much to be hoped, therefore, that they can be given full scope within the college, though this will raise administrative problems of the same kind, though not perhaps as inconvenient, as would have arisen from incorporation of the pathologists in a separate faculty. Representative and administrative machinery which was designed for small numbers in the remote past may need considerable alterations if a single body, with or without component faculties, has to represent several thousand people. Biologically, cell division is an inevitable accompaniment of growth; and to that extent the fissiparous tendency we have been discussing is no doubt a natural process. But if there are to be numerous independent or semi-independent bodies representing different specialties, ought there not to be some coordination between them? After all, the multicellular organism is more efficient than the unicellular-because the specialisation of its parts is balanced by integration. Today medicine in this country often seems like an incoherent group of unicellular organisms rather than a coordinated whole. Colleges, faculties, and Associations often cover the same ground as the specialist committees of the B.M.A., while a kind of cross-representation is provided by the Regional Hospitals’ Consultants and Specialists Association, the Central Consultants and Specialists Committee, and the Joint Consultants Committee ; and the Central Health Services Council has its own brood of specialist committees. From time to time an Academy of Medicine is proposed as a solution; but one may question whether the interchange of knowledge between the specialties could be carried out better than it is at present by medical societies, journals, and other agencies. Nor would an Academy readily impose coordination on all these diverse groups. Perhaps, like the British Commonwealth, we can only watch the new nations achieving independence, and hope for the best. Meanwhile, we may hope that the Royal College of Physicians, remaining primus inter pares, will not allow these secessions to trouble it unduly. Continuing to admit to its fellowship distinguished representatives of all medical specialties, including pathology, it can maintain and strengthen its who
are
unique position. Ski
Injuries
of the most popular of all participation sports, even in such lowland countries as Great Britain; and the suntanned tyro with a leg in plaster is now a common sight in our winter scene. The incidence of injury is higher in skiing than in most sports. An accident-rate of 0-5-1% per day is reported from Europe and North America1 2; the skier must SKIING is fast
1. 2.
becoming
one
Moritz, J. R. Amer. J. Surg. 1959, 98, 493. Earle, A. S., Moritz, J. R., Saviers, G. B., Ball, J. D. J. Amer. med. Ass. 1962, 180, 285.
therefore expect an injury sufficiently severe to take him to a doctor in every 100-200 days of skiing. Injuries are commoner in the novice; but, because of his slower speed, they are usually less severe than those in the experienced skier. The features of skiing which make it so dangerous include high speeds, the mechanical leverage of the skis, and the effects of cold and fatigue on muscular function. ERSKINE3 remarked that the momentum of a 150 lb. man travelling at 30 m.p.h. is 6600 ft. lb. per second. If the tip of his ski then catches an object and applies a twisting force, a moment is created at the ankle, which acts as the fulcrum, and the injuring force is the momentum multiplied by the distance from the boot to ski tip. The better the ankle is supported by the boot, the more likely are the tibia and fibula to fracture immediately above the boot; the stronger the bones the more likely is the force to be transmitted to ligaments, which may then rupture. When a great force is suddenly applied, as in falls at speed, bone, being rigid, will fracture; whereas if the force is gradually applied, as in the slower falls of the novice, the bone transmits the force to the ligaments of the knee which will rupture. According to WILLIAMS,4 novices sustain a higher proportion of knee and ankle strains, while practised skiers, in the series of BAUMGARTNER,Ssustained a higher proportion of lower-limb fractures. Lower-limb injuries almost always result from rotation strains due to striking an obstacle with the ski tip, " catching an outside edge " when turning, or simply crossing skis on a ski-tow. Forward flexion injuries, which are less common, also result in serious ankle injuries, one of the most disabling of which is a ruptured tendo achillis. A direct forward fall accompanied by divergence of the ski tips results in a spectacular fall picturesquely described " as an egg-beater ". In this fall, as in many in which release bindings free the ski from rigid contact with the boot, the projecting metal edges of skis may cause lacerations. Injuries to the upper limb are much less common; lateral falls on to hard snow or ice may fracture the tuberosity of the humerus, while falls on to an outstretched hand which holds a ski stick may result in a metacarpal fracture. Dislocation of the shoulderone of the more usual upper-limb injuries-often results from a fall at speed when the abducted arm is caught in soft snow as the body continues descending the slope.
Prevention of skiing accidents has attracted much interest. Release bindings, euphemistically called " safety bindings ", have been developed to release the boots from the ski when sharp twisting or flexion strains occur. Release bindings have become increasingly popular in the past ten years, and most skiers now use at least the lateral release pattern. But the number of different release bindings6 is an indication that the perfect " safety " binding has not been developed ; and it is important to obtain expert advice on the 3. Erskine, L. A. Amer. J. Surg. 1959, 97, 667. 4. Williams, J. A. Lancet, 1956, i, 96. 5. Baumgartner, W. Munch, med. Wschr. 1960, 102, 2220. 6. See Young, N. J. E. British Ski Year Book, 1961. Ski Club of Great Britain.
1389
lend themselves to the kind of graphic representation in which teachers of biochemistry delight. Mapped out, et al.2 find that since the introduction of release bindings there has been no decline in the incidence of ski injuries their interrelations tend to group themselves into clusin Sun Valley, Idaho. HowKINS,7 on the other hand, ters, each cluster centred around a more or less arbifound that the wearing of release bindings had decreased trarily chosen molecular fragment, and each fragment both the incidence and severity of injury in insured linked more or less closely to the lipid or carbohydrate British skiers. pathway. Among these focal fragments, structurally the loss of and are all confidence, Inexperience, fatigue simplest but metabolically one of the most difficult to important factors predisposing to skiing accidents. keep track of is the one-carbon unit. It exists at three There are no short cuts to experience, but good tuition levels of oxidation-methyl (CH3-), hydroxy-methyl ensures that it is acquired as painlessly as possible and (CH20H-), and formate (O=CH-)-and, in comis put to the best advantage. Loss of confidence is bination with nitrogen, as the important formimino closely related to inexperience and fatigue, and often radicle (NH=CH-). There is probably no one-carbonresults from unexpected changes in snow conditions. unit " pool " in the body in the sense that there is an Loss of confidence following injury seems important in ammonia or acetyl pool; nor do we now believe that the " predisposing to further injury; for KRAUS 8 reported organism depends on a steady supply of labile " that 40% of the knee injuries in his large series were methyl-group donors to meet its one-carbon-fragment re-injuries. Gradual reablement after injury is there- requirements. Compounds used to be tested for their fore important, and skiers would be wise to rejoin ski ability to provide such groups by observing whether they classes of a lower standard than that which they had could replace the classical methyl-group donor, methioreached at the time of injury. Accidents are commonest nine, in the homocysteine-supplemented diet of rats; towards the end of a day’s skiing 1-3 9-a feature associ- but most of these diets probably chanced to be deficient ated with changing snow conditions and fatigue. The not only in methyl groups but also in vitamin B12 and onset of fatigue, which is perhaps the biggest single folic acid. When these vitamins are supplied the adult factor predisposing to injury, can be delayed by (though probably not the newborn) organism can synthemeans of preparation, including pre-ski exercises, aimed sise methyl. and other one-carbon fragments from many at physical fitness. But for most participants, skiing is sources and transfer them enzymatically from one coma sensuous pleasure rather than an athletic pursuit; and pound to another. however much they are exhorted to sway on half-bent The role of desoxyribosenucleic acid (D.N.A.) and of knees for a month before their holiday or to spurn ski- ribonucleic acid (R.N.A.) in cellular multiplication is now lifts for the first five days, the majority will make their well established. The biochemical individuality of these first journey of the year on snow downhill from the top giant molecules-generally regarded as the repositories of a ski-lift using untrained muscles. These people and transmitters of genetic information-depends on the especially should learn when to stop; for one of the sequence and disposition of subunits derived from the greatest temptations in skiing is to take " just one more purine and pyrimidine nucleus; and experimental evidence suggests that in most cells the basic ring structure run down ". Perhaps the greatest advantage of spurning ski-lifts is that this deters the tired from taking another of these substances is synthesised rather than abstracted run when their bodies have had enough. ready-made from extracellular sources. Our understanding of how this is accomplished is very incomplete; but FIGLU there is little doubt that the shedding, incorporation, IGNORANCE of the second law of thermodynamics has amination, and transamination of one-carbon units are been publicised as a symptom of the exclusive literary essential steps in the process. These interchange and culture. Latin scholars may find the outrages committed transfer mechanisms are catalysed by enzymes; and to scientists on the classical tongues no less lamentable. some of these enzymes vitamin B2, folic acid, or both act by " FIGLU " cuts short the budding Virgilian hexameter, as coenzymes or intermediate carriers. Of the two vitaformiminoglutamic acid; and in this form it is beginning mins the sites of action of folic acid have been rather more to be used in medical parlance. Its interest to doctors clearly defined: it is known, for example, that after stepstems from the discovery that in folic-acid deficiency it wise reduction to tetrahydrofolic acid it acts as the transit replaces glutamic acid as the urinary end-product of stage for a hydroxymethyl group between deoxyuridylic histidine metabolism.1Q-13 This observation, first made and thymidylic acids, close precursors of thymine.14-16s on rats only nine years ago, has already inspired a numTHORELL and others who have studied the D.N.A. and ber of ingenious and useful diagnostic tests; and it has R.N.A. content of megaloblasts at successive stages of stimulated fresh interest in the biochemical ramifications development found that, while the quantity of D.N.A. in of the megaloblastic ansemias. the nucleus tends to remain unchanged, large amounts The turnover of aminoacids, purines, and pyrimidines Of R.N.A. accumulate in the cytoplasmJ7 18 This imbalin the body (unlike fat and carbohydrate metabolism) do ance could reflect the diminished capacity of these cells 7. Howkins, J. Brit. med. J. 1958, i, 1006. to synthesise D.N.A. and their consequent tendency to 8. H. Amer. med. Ass. 1414.
selection, fitting, and adjustment of bindings. EARLE
Kraus, J. 1959, 169, Staples, O. S. New Engl. J. Med. 1961, 264, 552. Silverman, M., Bakerman, H., Daft, F. S. Fed. Proc. 1951, 10, 247. Luhby, A. L., Cooperman, J. M., Teller, D. N. Proc. Soc. exp. Biol., N.Y. 1959, 101, 350. 12. Brohquist, H. P., Luhby, A. L. Fed. Proc. 1957, 16, 159. 13. Spray, G. H., Witts, L. J. Lancet, 1959, ii, 702. 9. 10. 11.
not
Girdwood, R. H. Brit. med. Bull. 1959, 15, 14. Friedkin, M., Kronberg, A. in The Chemical Basis of Heredity (edited by W. D. McElroy and D. Glass). Baltimore, 1957. 16. Knowles, J. P., Prankerd, T. A. J., Westall, R. G. Lancet, 1960, ii, 374. 17. Thorell, B. Acta med. scand. 1947, suppl. 200. 18. Riensner, E. H., West, R. Proc. Soc. exp. Biol. N.Y. 1949, 71, 651. 14. 15.