THE KNEE By DOUGLASS W. MONTGOMERY, M.D. SAN FRANCISCO

HET knee is a wonderful joint, . It was introduced much later and both for what it can do and is a term of regional anatomy. Curi- for what it symbolizes. ously enough, there are two poplitei, a It is a joint of multiple mo- popliteal fossa, or space, of the soft bility. It has flexion and extension, in parts, and a popliteal surface of the some positions slight rotation, and in femur. others a gliding motion backward and The “poples” had a special impor- forward. It has two cartilaginous cups tance for the Roman, and the term in its structure to give it resiliency in often meant the knee. The Romans taking up shocks, as in jumping, and wore kilts; the knee was bare, and also to permit the slight though impor- therefore in full view. Trousers were tant rotation before mentioned. Also the distinguishing garment of the bar- within its structure it has two strong barians—the Getae, Sarmatae, Gauls, ligaments which, when put upon the Germans and Britons—and for this stretch in full extension, lock the joint, reason were detested by the Romans.2 making the two principal bones of the The “feminalia” and “tibialia” which lower extremity one single stick. This the Emperor Augustus wore in winter is called the “screwing home’’ or “lock- were cloth swathings, the “feminalia” ing movement” of the joint.1 for the thighs (femora) and the “tibi- The knee, therefore, is mobile in alia” for the legs (tibia) respectively.3 many directions. It is rigid or lax, re- Augustus was a delicate and sen- silient or firm as its position or occa- sitive to cold, yet his physician, Anto- sion requires. It is abundantly fur- nins Musa, cured him of a wasting nished with strong ligaments and it is illness by giving him cold baths. This steadied in its position by the most made this treatment popular, and espe- powerful muscles in the body. And cially so with Musa himself who pre- these muscles have an unusually sen- scribed them for all sorts of ailments, as sitive tone, as shown by the symptom for example for the sore eyes of the poet, called the “knee jerk.” Its strong ex- Horace, who mentions feelingly being ternal ligaments protect its delicate in- douched with cold water in the middle ternal mechanisms, and it has a further of winter.4 protection in a bone shield, the patella, As the “poplites” were exposed, a placed over its front. favorite sword stroke with the gladi- THE POPLES ators was to hamstring the opponent, rendering him absolutely helpless. Vir- (the po pl ite al sp ace ) gil describes such a scene in which the “Poples” was the Latin name for hamstrung gladiator extends his neck, what we now call the popliteal space. according to custom, to receive the The word “popliteus” is not classical “coup de grace.” As going to the gladi- atorial games was as daily an amuse- his “poples” nor his timid back.7 ment in the Roman Empire as the “Poples” here again refers to the knee movies are with us, the audience must and hamstringing, and is literally un- have become quite familiar with ham- translatable by us, but conveyed a stringing. To see a man in the prime of lively impression to the Roman. life, and in the heat of a contest, ren- dered suddenly and absolutely im- THE KNEE AS A SOLE potent was indeed a dramatic sight. A moment’s reflection is enough to In a battle the retreating bare knees show that the knee is a sole and, as a must have flashed back temptingly to sole, practically bald. Yet it was only the pursuing enemy. Such was un- on seeing the worshipers advancing on doubtedly the case at the battle of Phi- their knees to the shrine of the Virgin lippi, where the short legs of Horace of Guadalupe that this fact dawned bore him, minus his little shield, back upon me. Just previous to observing to safety.5 this I had received a severe burn of the Here it is interesting to note that the lower limbs from exposure to the trop- popliteal space is particularly sensitive ical sun, in riding in a canoe the Pag- to pain. In fact, according to Strug- sanjan Rapids on the Island of Luzon. ghold, what are called the painful This burn was severe on the fronts of points of the cutaneous surface the legs and thighs but only a slight (Schmerzpunkte) are most closely set flush over the knees. Through this I in the bends of the large joints—regio became aware of a difference in anat- inguinalis, fossa poplitea, fossa cubiti omy and in texture of the skin in these and also in the fossa jugularis—all situ- situations. From long use as a sole in ations where large nerves and blood working and in worship the epithelial vessels come near to the surface. Of coating and other tissues over the knee these the popliteal space is the most have become more resistant. sensitive.6 Ehe pilo-sebaceous openings are the Much has been written on the before- weak points in the armor of the skin. mentioned incident in the life of Hor- For instance, the actinic rays of the ace, some asserting that it shows him tropical sun can enter the skin through to have been a coward; others that he the many large pilo-sebaceous openings was merely prudent; still others that it above and below the knee, but their was a deprecating joke to which Hor- relative absence or small size directly ace was much addicted. None of these over the knee contribute decidedly to commentators, however, mention the its insusceptibility to injury.8 sensitiveness of the popliteus to pain, and how it may have subconsciously THE GESTURES OF THE KNEE and fortunately lent an additional pair The high development of the human of wings to the heels of a man who sub- being and his erect posture cause the sequently added so much to the pleas- prominent and important knee joint to ure and instruction of mankind. reveal many of his deepest emotions. In another passage Horace warns the When the limb is straightened and unpatriotic and cowardly youth, who the knee joint locked securely, as in would seek by flight to escape death on standing at attention, it signifies the battlefield that, nevertheless, death strength and stability, and when flexed, will pursue him and will spare neither as in kneeling, it has indicated through- out the ages fear, humility and suppli- toms in the syndrome of fear, ranking cation. These gestures of servility, with pallor, a dry mouth with the timidity, longing, strength and master- tongue cleaving to the roof and a sink-

fulness give the knee a place along with ing feeling in the pit of the stomach, the face and hands as an instrument of khe knee is also an exponent of silent expression. character. There is the purposeful gait Tremulousness of the knees and their of a person going to a definite place, as knocking together are prominent symp- contrasted with a strolling gait. There is the loafing gait of our police as con- THE FEMININE KNEE trasted with the military bearing of the A lascivious alluring gait has long police of many foreign countries. There been recognized as an incitement to is the possessor of the lazy knee, slightly naughtiness. Isaiah for instance speaks bent, out of whom no effective work feelingly of the daughters of Zion who may ever be obtained. went mincing with their feet.11 That very sympathetic creature, the Because of the breadth of the pelvis dog, shows also his emotions in the a woman is more or less knock-kneed, knee. A dog first crawls with bended giving a feminine expression to the forelegs, and then rolls over with its stance. This unsteady appearance our paws in the air, as signs of obeisance. women accentuate by wearing the high- Sir Walter Langdon-Brown says that, heeled shoe. The Chinese woman previous to the World War, the dogs sought to attain the same effeminacy in Constantinople were divided into by binding the feet in infancy, making tribes, each having its separate district. them pointed nubs on which they were A dog had first to make this sign of sub- supposed to move with a swaying wil- mission before being permitted to enter lowy motion, held to be peculiarly a strange locality.9 charming. Elderly women arc still seen in the Chinese cities hobbling along on THE KNEE AS INDICATING AGE their deformed feet. It was stormy outside, with wind, Both with us and with the Chinese, rain and snow, and Horace exhorted however, it achieves, not an easy, but his friends to take advantage of the day a stamping or shuffling stumbling pro- and, while they were still young and gression quite different from Venus’s vigorous, to enjoy a glass of wine. In graceful majestic step.12 this passage the phrase: “Bum genua In one of his songs Horace compares virent” (while the knees are still green) the maiden, Chloe, to a timid fawn that, is employed, as it frequently was among with palpitating heart and trembling the ancients, to express the strength of knees, sought its dam throughout the the whole body.10 It also, as here, warns trackless forest. Horace tells the delicate against the approach of old age, as this shrinking Chloe that it is time for her to leave the protection of her mother, is the part of the body that first feels and that he is no fierce tiger or African its infirmities. “First the knee and then lion to do her harm, but to afford her the head,’’ is an old saying. loving protection.13 And this he relates There is the wobbling uncertain with the utmost simplicity but with an feeble progression of the aged, with the exquisite art, an art that has made the lax bent knee, and the equally uncer- song endure through the ages. The tain widespread weak-kneed gait of the exact date when this song was composed toddling infant, but what a difference may not be exactly known but, let it be in the vigor of the two! The one, eager granted that it was written twenty years to go and continually falling on its before Christ, it is now nineteen hun- rump, yet never defeated; the other, dred fifty-seven years old, and is still grateful for the comfort of an armchair. read with delight by many people. There are also the artistic values of A boy is quite different from a , the knee. Who has not admired the even while still a child. He walks with knee of Michelangelo’s “Moses’’? a firm tread, is eager to compete with other boys in games, is quick in anger joint, or of the sensitiveness of its at- and quick to forget, and is ever change- tendant muscles to any change in the able in his temper.14 position of the weight carried.

THE GRACE OF THE KNEE REFERENCES TO THE KNEE IN Ill the passage previously quoted it LITERATURE was by her step that Aeneas recognized If one wishes to get an idea of how his mother, Venus, as a true goddess. important the knee is in literature let In Paraguay the Guarani Indian him consult a concordance of the works maiden, dark as the tropical sun, rich in of that great exponent of human nature, actinic rays, can make her, and smoking Shakespeare, and he will find it re- a long black cigar, marches along in her ferred to one hundred eighty-one times. bare feet, wearing a loose flowing gar- The phrase, “on the knees of the ment and bearing on the head a large gods,” comes down from Homer, who jar of water. There is here no doubt of also uses the expression, “to break the the precise easy functioning of the knee knee,” meaning, to kill.15 Servius makes an interesting com- for foliage to make it more attractive, ment on the phrase, “genua amplexus” and saw on a neighboring hill some (the knees being embraced), in the pas- cornel bushes and myrtle stalks. He had sage in which describes how little luck, as at each attempt to secure Achaemenides, the destitute Greek sol- a branch, blood, not sap, oozed from dier found by the Trojans on the is- the branch, rendering it unfit for the land of the Cyclops, embraced the knees altar. A happy thought occurred to him. of Anchises, imploring him even for He might rip from the ground the en- death rather than leave him alone in tire myrtle stalk which, not being the horrible place. broken, would not bleed. He put forth In this passage Servius says that the his utmost strength and, to get a better “physici” (hence our word, physician) purchase, he knelt on the sand. Pres- say that the different parts of the body ently he heard an agonizing cry. It was are consecrated to different powers. The from Polydorus, a friend who had gone ear is consecrated to memory, and in to Thrace and had been murdered and fact it is often plucked in an effort to buried here, from whose body these recall a word or an event; the forehead myrtle stalks had sprung.18 This was to the protecting tutelary deity of the Virgil’s way of illustrating the doctrine family, and in venerating this deity the of the transmigration of the soul, and forehead is touched; the right hand is also of teaching the solidarity of life dedicated to fidelity, a natural infer- throughout the animal and vegetable ence; and the knees, which were also kingdoms. Years afterward Schwann touched, were dedicated quite fittingly demonstrated the cell as a common re- to the god of mercy.16 This last deity ceptacle of life for both, showing incon- is carried down through the Roman trovertibly the solidarity of the two.19 Church as “Our Lady of Mercy.’’ In Incidentally, through Virchow, the California for example there is a city medical profession received the mag- dedicated to Nuestra Seriora de la nificent gift of cellular pathology. Merced (Our Lady of Mercy). And Because of its literary beauty this pas- touching a part in order to heal it—the sage has had many admirers, as for in- holy touch—is also a remnant of the old stance the Spanish Jesuit, Cerda.20 In theology. it the knee has a chief place in express- A frequent literary device is to name ing the extreme vigor and the deter- a part for a whole as for example, Hor- mined effort Aeneas put forth to secure ace, while admiring a picture of gladi- the desired decoration for his altar. ators fighting, mentioned only the tense knee. This was quite sufficient to indi- THE KNEE AS THE SEAT OF LIFE cate the effort of the whole body.17 Life has always interested man, yet, In like manner, when Virgil wished in endeavoring to define it, we can only to express the great effort Aeneas put do so by mentioning its manifestations forth in tearing up a root he said that as: “A state of ceaseless change and he strained with his knees against the functional activity peculiar to organized sand. Aeneas in his long journey from matter.’’21 It is a common view to re- Troy to Rome landed in Thrace and, gard it as a spirit, that is, something as was customary, proceeded to erect breathed, from “spiro’’ (I breathe), and an altar to the gods. As in this instance in a beautiful passage Virgil employs the altar was especially dedicated to this word in the sense of the spirit of his mother, Venus, he looked around life.22 Aeneas, on the very point of leaving diligence sought for it in the lungs, and Carthage and deserting the heartbroken incidentally revealed the lesser circula- Elissa, exclaimed: “As long as memory tion of the blood, which to him was a lasts and the spirit of life rules my comparatively trifling matter. limbs ... I never shall forget you.’’ The naturalist, Pliny, thought the In this he of course acted like a sailor, seat of life to reside in the knee joint and he had been long enough at sea and, granting his way of thinking, it (some say three years) to acquire nau- was not a bad guess.23 He said that in tical ways. the knee there are two empty cups lying The connection between breathing to the right and left, and joined to- and life is of course obvious. When gether anteriorly by a ligament. And he breathing ceases life becomes extinct. added that, if pierced, the spirit of life The connection between breathing and escapes just as if the throat were cut. life has further implications, and good He found these cups to be delightfidly sound physiological ones. The liver and smooth and glistening, and they were the muscles constitute the furnace in vacant. Their beauty and their vacancy which the vast amount of heat neces- showed that they could only have been sary for our daily existence and for our occupied by something pure and in- work is produced. As Bayliss says, it is visible like a spirit. There were two a regular conflagration. The muscles of cups (gemina) typifying the male and the lower extremity are the largest in female principle, and these, as before the body, and while the man is erect, mentioned, were joined together by the even though not walking, they are in transverse ligament, evidently a mar- a postural sense ever active. When this riage bond. When the knee was injured part of the human furnace flags through the man was rendered utterly helpless. lack of exercise the vital forces also lag. Certainly something essential to life, The impulsion to active movement the very spirit of life, had been affected. grows less with advancing age, hence Pliny could also have stated that in the increasing necessity of taking fre- front of the knee there is a shield, the quent light exercise to supply oxygen patella, and shields in his day were im- to the furnace. In no other way than portant pieces of defensive armor, de- by exercise may oxygen be introduced fending the life of the bearer. Besides and the food properly burnt. This also this, he had the sentimental and artistic accounts for the constitutional gravity values of the knee, and a noble litera- of injuries to the knee or foot, so im- ture to support him in his opinion. peding exercise. In practice it is inter- Finally, Rabelais mentions a town in esting to note the instinctive fear the the province of Berry, France, called laity has of what they call “water on the St. Genou (St. Knee). It appears that a knee.’’ pilgrim called Weary foot came from that town, and that it also was distin- THE SEARCH FOR THE SEAT OF LIFE guished as the residence of the old she- Ebe search for the elusive quality doctor who applied too strong an astrin- called life has shifted from place to gent to the fundament of Gargamelle, place throughout the generations. At who suffered from prolapse of the one time it was thought to lie in the rectum in giving birth to Gargantua. pineal gland, or in the liver, and fre- St. Genou himself, after whom the town quently in the heart. Servetus in his was named, was not an altogether amiable saint as, far from curing, he or the weakness of senility; mechanic- afflicted men with gout.24 ally it is the most marvelous joint in the SUMMARY body; and it has been delightfully em- I'he knee expresses some of our deep- ployed in literature and art by the est griefs. It shows character; it indi- greatest exponents of human nature and cates age, whether infancy with its vigor behavior.

Ref ere nces 1. Gray’s Anatomy, p. 347. 11. Isaiah, 111, 16. 2. The article on “breeches” in the Cyclo- 12. “. . . ct vera incessu patuit dca.” paedia by Abraham Rees, London, (. . . and by her step the true goddess 1819. is revealed.) Virgil’s Aeneid, 1, 405. 3. C. Suetonii Tranquilli de xii . Caesaribns 13. Horace, C 1, xxhi , 8. “. . . et corde et Liber secundus. D. Octav. Caesar Au- genibus tremit.” (. . . Chloe trembles gustus, 82. “Augustus neque frigora both in heart and knees.) neque aestus facile tolerabat.” (Au- 14. Horace. Ars poetica, 158. “Pede certo gustus did not tolerate easily either signat liumuni.” (He plants his foot on heat or cold.) the ground firmly.) 4. Horace: “Gelida cum perluor unda per 15. Dacier, Loc. cit. medium frigus.” (Now that I am 16. Servius: Virgilii cum comentum, Aeneid, doused with cold water in the middle 111, 607. of winter.) Epist. I, 15, 3. 17. Horace, S 11, 7. 97. “Miror proelia picta 5. “Tecum Philippos, et celerem fugam contenta poplite.” (I admire the paint- sensi, relicta non bene parmuta.” ing of the contest with the knee put (With thee I have endured the terror well on the stretch.) of the battle of Philippi, in which my 18. Virgil, Aeneidos. Lib. hi , 38. “Aggredior, little shield was not altogether glori- genibusque adversae obluctor arcnac,” ously left behind.) Horace, C 11, 7, 9-10. (Again I advance to the attack, and I 6. Physiologie u. Chemie d. Haut. Die strain with my knees pressed against Schmerzpunkte, von M. V. Frey u. H. the adverse sand.) Rein, Handbuch d. Haut u. Ge- 19. Schwann, Theodore. (1810-1882), profes- schlechtskrankheiten, von J. Jadas- sor of anatomy at Louvain and founder sohn, Bd. I/2, 1929, S. 145. of the cell theory. He compared ani- 7. Horace, C ill, 2-15. “Mors nec—parcit im- mal and plant cells, and described the bellis juventae poplitibus timidoque origin of tissues from cells. tergo.” (Death does not spare either 20. P. Virgilii, Maronis Aeneidos Libri sex the poples or the timid back of the a Joanne Ludovico de la Cerda, Tole- unwarlike youth.) dano e. Societate Jesu. 8. Erythema solare, as so many erythemata, 21. Oxford Dictionary. begins at the follicular openings as red 22. “. . . dum mcmor ipse mei, dum spiri- points. Die Lichterkrankungen der tus, hos reget artus.” (. . . while mem- Haut, von Prof. Dr. W. Hausmann, u. Priv. Doz. Dr. H. Haxthausen, Urban ory itself for me shall last, while the u. Schwarzenberg, Berlin, 1929, S. 26. breath of life [spiritus, from spiro—I 9. Langdon-Brown, Sir Walter, On Getting breathe] shall rule these limbs.) the Rash Out. British Journal of Aeneid, iv, 336. Dermatology & Syphilis, September, 23. ‘‘Quia incst iis vitalitas. Namque in ipsa 1937, P- 350. genu utriusque commissara dextra 10. Horace, Epod. xm, 4. E. C. Wickham levaque a priore parte gemina quae- quotes Homer as placing the seat of dam buccarum inanitas incst, qua strength in the knees. “Genua frequen- perfossa ecu jugulo spiritus ltigit.” ter pro roboris propria sede.” Orelli’s Dacier’s Horace, Od. v, 13. 6. (Note). comment. Also Dacier, T. V., p. 196. 24. Gargantua. Chapt. vi & xi.v.