March, 1964 P H Y S I O T H E R A P Y Page 3 A Racial Comparison of the Evolution of the Knee Joint By P. K E E N Senior Surgeon, N on-E uropean H ospital, Johannesburg. Man’s rise to th e e rec t p o stu re has c au sed a re o rie n ta tio n of every p a rt o f his o rg a n ism . M o s t o f th ese c h an g e s have been studied in g re at d e ta il a n d th e lite ra tu re o n th e subject is immense, b u t it is e x tra o rd in a ry how little in te rest has been centred o n th e k n e e jo in t. In dealing w ith th e h ind o r lo w e r lim b m o st o f th e in te rest has been c en tred o n th e f o o t a n d its e v o lu tio n . D . 3. Morton fo r in stan c e, in disc u ssin g fu n c tio n a l d iso rd e rs of the foot, w ro te :— “ N o p a rt o f th e b ody offers a m o re c o m p le te re co rd of the e v o lution o f m a n k in d th a n th e feet. T h e y possess also a hidden in te rn a l m ec h an ism w hich seem s m ag ically to neutralise th e fo rce o f g ravity. O n ly a m a n w ith the m uscular d e v elo p m en t o f a S a n d o w c o u ld , as in ju g g lin g , pass a 50 lb. m eta l b all to a n d fro fro m th e p a lm o f one hand to th e o th e r, yet a 5- o r 6 y e ar-o ld c h ild , play fu lly running, to sses a n e q u a l lo ad (b o d y w eight) fro m o ne foot to the o th e r as e asily a n d lig h tly as th e av era g e a d u lt would ju ggle a b a se b all. Feet a re specifically desig n ed by n a tu re to give m aste ry over the g re at fo rce o f g ravity. C lassific a tio n o f th e fo o t with such highly specialised o rg a n s a s th e eye a n d the ear m ay seem su rp risin g , b u t is b o th so u n d a n d c o rre c t. By the specialized o c u la r m ec h an ism , w e have d irec t contact a n d a p p re c ia tio n o f su rro u n d in g lig h t, as well as of reflected lig h t w aves w hich re g iste r th e c o lo u r a n d form o f all s u rro u n d in g ob jec ts. L ikew ise, th e specialised mechanism w ith in o u r e a rs su p p lies in tim a te c o n ta c t with the so u n d w aves th a t fill th e a ir. H u m a n feet a lso are specialised s tru c tu re s a d a p te d fo r d ire c t in te ra c tio n with gravity as im posed by ve rtica l b o d y p o s tu re a n d the bipedal m ode o f lo c o m o tio n .” The knee jo in t in m a n , how ever, has c h an g e d its fu n c tio n even m ore th a n th e fo o t a n d th e sp ecialised a n d re latively recent ev o lu tio n to a jo in t w hich c a n be fu lly e x te n d ed and even hyperextended is m o re d ra m a tic , w hen th o ro u g h ly analysed, th a n a n y o th e r ty p e o f e v o lu tio n in th e p ro g ress from the q u a d ru p e d a l to th e bip ed a l fo rm o f lo c o m o tio n . F rom an u n im p o rta n t jo in t w ith a lim ite d ra n g e o f movement, w hose m ain fu n c tio n w as to c u sh io n a relativ ely small a m o u n t o f th e fo rce o f g ra v ity a n d to fa c ilita te the [propulsive m ovem ent o f th e b ody, it has b ecom e a jo in t 'designed to b ear th e w h o le w eight o f th e b o d y w ith a ra n g e of m ovem ent fo r w hich th e jo in t is n o t s u ita b ly designed. M an is the o n ly an im a l w hich c a n fully e x te n d th e knee joint, and he can even hyp e rex ten d it. F ro m a jo in t, w hich in all anim als is a lm o st e n tire ly u n d e r m u sc u la r c o n tro l, it has evolved a c o m p lica te d lo ck in g m e c h an ism on e x te n ­ sion, and in h y p e rextension is a lm o s t e n tire ly u n d e r lig a­ m entous c o n tro l. It is n ot to be w o n d e red a t th a t in th is p ro c ess o f e v o lu tio n mechanical w eaknesses sh o u ld m a k e th em selves e vident and the trem en d o u s g ain s a tta in e d , w ith o u t w hich th e bipedal form o f lo co m o tio n w o uld be im p o ssib le , have their c o u n te rp a rt in c e rta in deficiencies in th e b ony, liga­ m entous a nd m u sc u la r c o m p o n e n ts o f th e k n e e jo in t. It is im p o rta n t a t th is stage to review th e c o u rse o f e vents in the e v o lution o f th e pelvic lim b fro m th e q u a d ru p e d a l to the bipedal fo rm o f lo c o m o tio n . In q u a d ru p e d a l a n im a ls the m ain fu n c tio n o f th e pelvic lim b s is e le v a tio n o f th e posterior h a lf o f th e bod y w eight a n d o f p ro p u ls io n o f the body. T he c en tre o f g ra v ity o f th e b o d y lies betw een the hind a n d forelim bs, a n d th e hind lim b fu n c tio n s as a propulsive lever w hen it ex erts p re ssu re a t rig h t a n g le s to its axis. This is d o n e m ain ly by th e m uscles on th e p o ste rio r aspect o f the th igh, biceps fe m o ris se m im e m b ra n o su s a n d se m ite n d in o s u s a c tin g o n th e h ip a n d knee jo in ts . O nce th e h in d lim b is re tra c te d , th a t is a t a n a n g le o f m o re th a n 90° to th e a x is o f th e body, ex te n sio n o f th e k n e e a n d a n k le jo in ts in cre ases th e p ro p u lsiv e fo rce , a n d p u sh e s th e bod y fo rw a rd s. T h e fo llo w in g figures q u o te d by H . A . H a x to n confirm th e im p o rta n c e o f th e m uscles o f th e p o s te rio r a sp e c ts o f th e t h ig h : “ H a u g h to n (1873) fo u n d th a t th e s e m u sc le s c o n s titu te a p p ro x im a te ly 3 8 % , by w eight, o f th e m u sc le s a c tin g on th e h ip jo in t. T h e biceps fe m o ris is p a rtic u la rly m assive, a n d in a p o w e rfu l a n d a gile a n im a l su c h a s th e tiger it fo rm s a larg e tria n g u la r m u sc le w hich e x te n d s fro m its p ro x im a l a tta c h m e n t to th e ischial p a te lla , to th e h ead o f th e fib u la a n d th e g re a te r p a r t o f th e a n te r io r b o rd e r o f th e tib ia , a n d e ven in to th e c a lc a n e u m beside th e te n d o c a lc a n e u s. (H a u g h to n , 1871, 1873.) A sim ila r in se rtio n fo r th e large biceps fe m o ris has been d e scribed in th e d o g (B radley, ’4 3 ; E lle n b erg e r a n d B a u m , 1891.) a n d in th e h o rse (B radley, ’2 0; L u a rd , ’35). T h is m uscle its e lf a c c o u n ts fo r a b o u t 18% o f th e h ip -jo in t m u s c u la tu re in q u a d ru p e d s (H a u g h to n , 1873). I n th e d o g a n d horse th e se m ite n d in o s u s is a ls o a very p o w e rfu l m uscle, the in se rtio n o f w hich re ac h es fa r d o w n th e tib ia a n d , in p a rt, to th e c a lc a n e u m . C ro s s se c tio n s o f th e th ig h s in th ese a n im a ls (E lle n b erg e r a n d B a u m , 1891; B radley, ’20) sh o w th a t th e h a m s trin g g ro u p o f m uscles is m u c h b u lk ie r th a n th e q u a d ric e p s fe m o ris .” H a x to n h im self d issected o u t th e q u a d ric e p s a n d th e h a m s trin g s in a series o f sp e c im en s o f th e c at, ra b b it a n d r a t a n d fo u n d t h a t th e to ta l w eight o f th e h a m s trin g s w as a lm o s t e x a c tly tw ice th a t o f th e q u a d ric e p s . F u r th e r he s ta te d “ I n m a n , o n th e o th e r h a n d , th e re la tiv e sizes o f these m u sc le s a re v ery differen t. In th e th ig h th e g re a t q u a d r i­ c ep s m u sc le m a s s o v e rsh a d o w s its o p p o n e n ts a n d in fa ct, a s C o w p e r sh o w ed 220 y e ars a g o , it w eighs tw ice as m u ch a s d o th e h a m strin g s. T h e re la tiv e w e ights a re, th ere fo re, a lm o s t e x ac tly th e inverse o f th o se fo u n d in th e q u a d r u ­ peds. T h e q u a d ric e p s is m a in ly a 1 -joint m u sc le a ctin g o n th e k nee j o in t, a n d o n ly a sm a ll c o m p o n e n t, th e re c tu s fe m o ris, a c ts o n th e hip jo in t. T h e h a m strin g s fo rm a re la tiv e ly sm a ll p a r t o f th e m u s c u la tu re o f the th ig h , c o n s titu tin g o n ly 1 6 -6 8 % o f th e hip jo in t m uscles (H a u g h to n , 1873). T h e ir te n d o n s a re in se rte d in to the p ro x im a l en d s o f th e leg b o n e s, a n d th ey p a ss q u ite close to th e axis o f th e k n e e j o in t, so t h a t th e y w o rk a t a c o n ­ s id e ra b le m ec h an ic al d isa d v a n ta g e in flexing th e k n e e.” “ In su m m a ry o f th is s tu d y in c o m p a ra tiv e a n a to m y it c a n be sta te d th a t th e la rg e st m u sc le s in th e h ind lim bs o f q u a d ru p e d s a re th o se w h ich a c t o n tw o o r m o re jo in ts , w hile th e 1-jo in t m uscles p re d o m in a te in th e low er lim b s o f m a n .” T h e sh iftin g o f th e b o d y ’s c e n tre o f g ra v ity to a p o sitio n a lm o s t v e rtic a lly a b o v e th e k n e e j o in t has c o n sid e ra b ly a lte re d th e m u sc u la r p o w e r re q u ire d . L ittle m u s c u la r effort is no w re q u ire d o f th e p o s te rio r th ig h m uscles to m ain ta in th e e rec t p o s tu re a n d th e k n e e jo in t h as becom e p a r t o f the p e d esta l s u p p o rtin g th e b o d y w eight. S o lid ity is th e m ain re q u ire m e n t a n d th e k n e e jo in t in m a n has now a c q u ire d a lo ck in g m ec h an ism a n d lig a m e n to u s c o n tro l, d e sp ite th e g re a t in cre ase in ra n g e o f m o v e m e n t, w h ich is n o t fa r s h o rt o f m ira c u lo u s . In th e fo rw a rd m o v em e n t o f th e b o d y th e k nee jo in t has a ls o a c q u ire d a new fu n c tio n . In q u a d ru p e d s it is a n im p o r­ ta n t fa c to r in th e p ro p u lsiv e m o v em e n t o f th e b ody, in m a n it is o n e o f th e m ain fa c to rs in re sistin g th e fo rw a rd m o v em e n t o f th e b ody, c aused by sh iftin g th e c e n tre o f the g ra v ity o f th e b o d y v e n tra lly . In o th e r w o rd s , in m a n th e low er lim b has a cq u ire d a m o re im p o rta n t b ra k in g a c tio n , a n d fo rw a rd m o v em e n t is in itia te d by sim p ly sh iftin g th e c e n tre o f g ra v ity fo rw a rd , a n d a llo w in g g ra v ity to tak e effect. A s fa r as th e k n e e jo in t is c o n c e rn e d th is new fu n c tio n re q u ire s s tro n g e x te n so r m uscles a n d hence th e p re p o n d e r- R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) Page 4 P H Y S I O T H E R A P Y March, 1964 ance o f th e q u a d ric e p s a n d ga stro cn e m ii in m a n o v e r the h a m strin g s. A s fa r as th e knee jo in t is co n ce rn ed th e final re su lt is th a t in a cq u irin g th e e rec t p o sitio n m a n h as h a d to : (1) stre n g th e n ' th e b o n y a rc h ite c tu re o f th e k nee jo in t to e n ab le it to ta k e the e x tra w eight c au sed by th e sh ifting o f th e b o d y ’s c e n tre o f g ra v ity ; (2) a d a p t th e k nee jo in t to e n a b le it to g ain full ex te n sio n a nd th u s fa c ilita te its p a rtic ip a tio n in the p e d esta l fu n c tio n o f th e h in d lim b ; (3) m odify th e m uscles o f th e knee jo in t to e n ab le it to assist th e re st o f th e pelvic lim b in the b re a k in g a c tio n d u rin g fo rw a rd m ov em e n t. T h is h a s b een acc o m p lish e d ; (1) by in cre asin g th e size o f th e b o n e s fo rm in g the k n e e j o in t; (2) by evolving a lo ck ­ ing m echanism in full e x te n sio n ; (3) by m o difying th e fu n c ­ tio n o f the c o lla te ra l a n d c ru ciate ligam ents, a n d e la b o ra tin g th e m edial c o lla te ra l lig a m e n t; (4) by e n la rg in g the q u a d ri­ ceps m uscle, a n d n a rro w in g th e h a m strin g s to such a n e x te n t th a t the te n d in o u s p o rtio n o f o n e o f th e m has p ro b a b ly b ecom e th e lo n g p a r t o f th e m edial c o lla te ra l ligam ent. H a v in g e stab lish e d th e p o sitio n o f th e knee j o in t in m a n ’s b ip ed a l fo rm o f lo c o m o tio n it is n o w p o ssib le to fit in th e c o m p a ra tiv e findings in E u ro p e a n a n d B a n tu k nee jo in ts in to th e p ictu re. S u m m arisin g these, it h a s been n o ted th a t in th e bon y s tru c tu re o f th e k n e e j o i n t :— (1) R e la tiv e to its len g th , th e E u ro p e a n fe m u r is w ider a t th e level o f th e k nee jo in t th a n th e B a n tu femur.. (2) T h e low er e n d o f th e E u ro p e a n fe m u r is w ider th a n th e B a n tu fe m u r w hen o ne c o m p a re s th e tran sv erse a n d a n te ro p o s te rio r d iam e te rs a t th e level o f the c ondyles. T h is is show n by th e re altiv e indices o f 7 7-4 a n d 80-5. (3) T h e in cre ase in w id th in th e E u ro p e a n fe m u r a p p ea rs to be d u e to a n increase in the in te r-c o n d y la r space, a n d th e re seem s to be a ten d e n cy to sp lay in g o u t o f th e condyles. (4) T h e u p p e r e n d o f th e tib ia a lso has a ro u n d e r sh a p e in th e B a n tu , as show n by th e re la tiv e indices o f 66-53 and 6 3-86. (5) T h e p a te lla in th e B a n tu is relativ ely sm aller. (6) T h e tib io -fe m o ra l index in th e B a n tu w as 86 1 as c o m p a red to 82 • 1 in th e E u ro p e a n . In th e lig a m e n to u s s tru c tu re o f the k n e e jo in t th e fo llo w ­ ing c o m p a ra tiv e findings h ave b een n o t e d ;— (7) T h e m ed ia l c o lla te ra l lig a m en t is a la rg e r a n d m o re com plex stru c tu re in th e B a n tu . (8) T h e m ed ia l c o lla te ra l lig a m en t has a m u ch closer re la tio n to th e a d d u c to r m ag n u s te n d o n in th e B a n tu . (9) T h e fib u la r c o lla te ra l ligam ent is stro n g e r in th e B a n tu . (10) T h e c ru c ia te lig a m en ts a re th ic k e r in the B a n tu a n d have a m o re vertical c o u rse in b o th planes. (11) T h e a n te rio r c ru c ia te is m o re in tim a te ly fused w ith th e m edial m eniscus in th e B a n tu . (12) T h e m enisci a re less m o b ile in th e B a n tu . H o w d o th ese findings fit in to th e e v o lu tio n o f th e knee jo in t fro m th e q u a d ru p e d a l to th e bip ed a l fo rm o f lo co ­ m o tio n ? T a k in g th e m in o r d e r:— 1, 2 a n d 4. T h e b o n y a rc h ite c tu re o f th e k n e e jo in t in th e E u ro p e a n suggests th a t it is b e tte r fitted to a c t in weight b e arin g , b e ing m o re m assive a n d w ider. 3. T h e w id ening o f th e in te rc o n d y la r space w h ich h a s given th e E u ro p e a n k n e e jo in t a larg e r w e ight b e arin g a rea , has w e akened it a s fa r a s th e fu n c tio n o f th e c ru c ia te s is c o n ce rn ed . T h e c ru ciate s a re m o re o b liq u e in b o th p lan es in th e E u ro p e a n a n d have lo st to a g re a te r e x te n t th eir orig in a l fu n c tio n as in te rn a l c o lla te ra l ligam ents. 5. I n th e B a n tu th e relativ ely sm a lle r p a te lla (a sesam oid in the q u a d ric e p s ten d o n ) suggests th a t th e increase in size o f th e q u a d ric ep s, so im p o rta n t in th e b ip ed a l fo rm o f lo c o m o tio n , h a s n o t re ac h ed th e sam e sta g e as in the E u ro p e a n . 6. T h e tib io -fe m o ra l index in th e tw o ra ce s suggests th a t in th e B a n tu th is index te n d s to th e sim ia n type. 7. a n d 8. If, as has been suggested, th e superficial long fibres o f th e m ed ia l c o lla te ra l lig a m en t a re th e re m n a n ts o f th e sciatic p o rtio n o f th e a d d u c to r m ag n u s, th en it w ould a p p e a r th a t th e B a n tu k nee jo in t h a s re ta in e d a n earlier sta g e o f its e v o lu tio n . T h e m a rk e d d istin c tio n a n d easy s e p a ra tio n o f th e d eep s h o rt fibres fro m th e lo n g superficial fibres in th e B a n tu stre n g th e n s th is view point. 10. T h e re latively larg e r size o f th e c ru ciate s in the B a n tu , a n d th e ir m o re v e rtica l d ire c tio n in b o th planes, d u e m ain ly to th e n a rro w e r in te rc o n d y la r space, m akes th em m o re effective as c o lla te ra l lig a m en ts, b u t less effective in p re v e n tin g a n te ro -p o s te rio r m o v em e n t o f the tib ia on th e fe m u r. T h is a lso suggests th a t th e c ru c ia te s in th e B antu h a v e m a in ta in e d to a g re a te r d egree th e ir o rig in a l function. 11. a n d 12. T h e c lo ser a sso c ia tio n o f the a n te rio r c ru c ia te a n d th e m edial m eniscus a n d th e relativ ely reduced m o b ility o f the m enisci in th e B a n tu b o th suggest th a t the B a n tu k n e e jo in t has n o t evolved to the sa m e e x te n t as the E u ro p e a n k nee jo in t a s fa r as th e e rec t p o s tu re is concerned. I t w o u ld th e re fo re a p p e a r th a t a ll th e differences noted in th e k n e e jo in t in th e tw o ra ce s fit in to th e p a tte rn o f thd e v o lu tio n o f th e knee jo in t fro m th e q u a d ru p e d a l to tht? b ip ed a l fo rm o f lo c o m o tio n a n d th a t th e B a n tu k n e e joint is relativ ely m o re re ta rd e d . In o th e r w ords the E u ro p e a n k n e e jo in t has progressed fu rth e r a n d a d o p te d a m o re specialised fo rm o f th e erect fu n c tio n . T h is d o e s n o t necessarily m ea n th a t th e E u ro p ea n knee j o in t is a b e tte r k nee jo in t. In fa ct it will be shown th a t in a c q u irin g th is specialised sta b ility it h a s m ad e itself m o re v u ln e ra b le to c e rta in ty p es o f tra u m a , b u t it w ould a p p e a r th a t th e E u ro p e a n k n e e j o in t is slightly m o re suited to c arry in g th e bod y w eight a n d to e n su rin g sa fer a n d m ore ra p id fo rw a rd m ov em e n t in w a lking. W h eth er th is applies to ru n n in g as well is d o u b tfu l, a n d this a sp e ct, w hich has n o t been investigated in this th esis will be co n sid ere d and d iscussed late r. Is it p o ssib le n o w to fit th e p a th o lo g ic a l differences noted in th e tw o ra ce s in to th is e v o lu tio n a ry p a tte rn ? B riefly th e differences n o te d a r e :— (1) T h a t p a ra -a rtic u la r o ssification in th e region o f the m ed ia l c o lla te ra l lig a m en t is m u c h m o re co m m o n in th e B a n tu th a n in th e E u ro p e a n . (2) t h a t p o st tra u m a tic o s te o -a rth ritis in th e k nee jo in t is m o re c o m m o n in th e B a n tu th a n in th e E u ro p e a n , and has a n e a rlie r age-incidence. (3) th a t m en iscal injuries in th e knee jo in t a re m u ch m ore c o m m o n in th e E u ro p e a n th a n in th e B a n tu . Para-articular Ossification or Pellegrim i-Stieds Syndrome: / T h e fo llow ing p o in ts have been re a so n a b ly well estate, lished : (1) th a t tra u m a is th e c o m m o n e st cause o f this condition. (2) th a t p e rio ste al a v u lsio n n e a r th e a d d u c to r tubercle a c c o u n ts fo r th e m a jo rity o f these cases. (3) th a t th e ossification d o e s n o t a c tu a lly ta k e p lace in th e lig a m en t itself b u t m o stly on its o u te r su rfa ce and in th e spaces betw een th e lig a m en t, th e a d d u c to r m uscle te n d o n a n d the c o n d y le o f th e fem ur. (4) th a t th e c h a ra c te ristic c re sc e n t-m o o n sh a p e o f the ossified a re a is d u e to th e sh a p in g o f th e ha em ato m a by the fascial coverings o f th e region. (5) th a t th e lesion behaves clinically like th e ossifying p ro c ess o f a m y o sitis ossificans a n d th a t th e trea tm e n t is sim ilar. Is it p o ssib le to asso c iate th e a n a to m ic a l differences noted in th is a re a w ith th is ten d e n cy o n th e p a r t o f th e B a n tu to in ju ry a n d su b s e q u e n t o ssific atio n ? T h e closer a n atom ical r e la tio n betw een th e a d d u c to r m ag n u s te n d o n a n d th e u pper in se rtio n o f th e m edial c o lla te ra l lig a m en t w o uld a p p ea r to be a v u ln e ra b le a re a in th e B a n tu k nee jo in t. A s h a s been n o te d , in the E u ro p e a n it is o n ly ra re ly th a t fibres pass fro m th e a d d u c to r m ag n u s te n d o n to th e u p p e r insertion R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) March, 1964 P H Y S I O T H E R A P Y Page 5 f the m edial c o lla te ra l ligam ent a n d the u su a l finding is a H tinct gap. In th e B a n tu , how ever, it has b een n o te d th a t • t h e large m ajo rity o f cases th e re is a close re la tio n betw een the a d d u c to r m a g n u s te n d o n a n d th e m edial c o lla te ral ligam ent. This p o o r a n a to m ic a l c o n n e c tio n betw een tw o fixed p o in ts ,.he a d d u c to r tu b e rc le a n d u p p e r in se rtio n o f the m edial collateral ligam ent) c a n have little o r n o fu n c tio n a l effect a n d c an only be a v u ln e ra b le area. It is suggested t h a t th e ty p e o f knee w ith tw o in se rtio n s a n d num ero u s fibres co n n ec tin g th e tw o is p a rtic u la rly prone to perio ste al a v u lsio n a n d su b s e q u e n t ossification. Any u n d u e o r u n n a tu ra l stra in o n th e a d d u c to r m ag n u s t e n d o n o r th e m ed ia l c o lla te ra l lig a m en t w o u ld re su lt in the fibres o f th is w eak lin k te a rin g a n d as th ese fibres pass over a nd a re a tta c h e d to th e p e rio s te u m in th is a re a , it would be n a tu ra l to e xpect p e rio ste al te a rin g in a larg e percentage o f cases. T h e re su ltin g h a e m a to m a c o n ta in in g released o ste o b la sts w o uld ten d to fill th e n a tu ra l spaces in this a rea , a n d th e fascial coverings w o u ld m o u ld it to the classical c rescent shape. It is th ere fo re su ggested th a t th e a n a to m ic a l differences | n o t e d in th is a re a in th e tw o races a c c o u n t fo r th e frequency of this fo rm o f p a ra -a rtic u la r ossification in th e B antu. Post Traumatic osteo-arthritis: Ts it possible to a c c o u n t fo r th e re la tiv e freq u e n c y a n d earlier a p p e a ra n c e o f th is c o n d itio n in th e B a n tu in the light o f this d iscussion ? O steo-arthritis is a deg en e rativ e fo rm o f a rth ritis , and though septic foci, p o o r g eneral h e a lth a n d o th e r fa c to rs have been in crim in a te d , wear a n d tea r in a pressure bearing joint is a basic fa c to r in the etiology o f the pathological picture o f osteo-arthritis. It is n o t su rp risin g th e re fo re , th a t th e low er lim b a n d spine are th e c o m m o n e st sites o f o ste o -a rth ritis, b o th in the E u ro p ea n a n d in th e B a n tu . T h ese tw o re g io n s in q u a d ru p ed s d o n o t fu n c tio n p a rtic u la rly as w eight bearin g joints, a n d it is n o t su rp risin g th a t they s h o u ld be th e first to suffer in the b ip ed a l p o sitio n . It is inte restin g to n o te th a t in E u ro p e a n s sta tistic a l figures show th a t th e sp in e is th e c o m m o n e st site o f o ste o ­ a rthritis w hereas in th e B a n tu , th e k nee jo in t tak e s first place in the freq u e n c y list. M eniscal lesions a re a c o m m o n cause o f o ste o -a rth ritis in E u ro p e a n s, a n d yet in th e B a n tu , despite the a b se n ce o f m en iscal lesions, o ste o -a rth ritis is still relatively m o re co m m o n . T h is suggests th a t th e B a n tu knee jo in t is n o t a s well e q u ip p e d fo r w eight b e arin g as the E uropean jo in t, a n d re a c ts to th e sam e w e ar a n d te a r m o re rapidly by sho w in g signs o f o ste o -a rth ritis. I f it is a ccepted th a t th e B a n tu k n e e jo in t h a s n o t re ac h ed th e specialised fo rm o f w eight b e arin g o f th e E u ro p e a n knee jo in t, a n d h as re ta in e d to a g re a te r e x te n t th e c h a ra c ­ teristics o f th e q u a d ru p e d a l k nee jo in t, th e n it m u s t be a cc ep te d th a t th e B a n tu k nee jo in t is m o re likely to suffer fro m th e w ear a n d te a r o f weight b e arin g , a n d it w o u ld be n a tu ra l to expect a n e a rlie r a p p e a ra n c e o f o ste o -a rth ritis. The relative frequency o f meniscal lesions in the European: T h e a n a to m ic a l a n d p h y sio lo g ic a l differences n o te d in th is d iscussion a r e :— (1) T h a t th e m enisci have a g re a te r range o f m o b ility in th e E u ro p e a n as c o m p a re d to th e B a n tu . (2) T h a t th e re is a c lo s e r lig a m en to u s re la tio n betw een th e a n te rio r c ru c ia te a n d th e m edial m eniscus o f th e B a n tu as c o m p a re d w ith th o se o f the E u ro p e a n . T h e re seem s little d o u b t th a t th e e x tra m o b ility a n te rio rly o f th e E u ro p e a n m edial m eniscus is d u e to th e fu lle r ex­ te n sio n a n d h y p e rex ten sio n o f th e E u ro p e a n knee jo in t, a n d th a t th is h a s led to a stre tc h in g a n d d isa p p e a ra n c e o f th e fibres w hich in low er a n im a ls p a ss fro m th e a n te rio r c ru ciate to th e a n te rio r h o rn o f th e m edial m eniscus a n d help to k eep it in p o sition. T h u s a sim ila r c o n d itio n exists betw een th e a n te rio r c ru c ia te a n d th e m edial m eniscus as e x ists betw een the m edial c o lla te ra l lig a m e n t a n d th e te n d o n o f th e a d d u c to r m agnus. I n o n e case it has led to a v u ln e ra b le a re a in th e B a n tu a n d in th e o th e r case h as left a c o m p a ra b le v u ln era b ility in th e E u ro p e a n . Tt w o u ld a p p e a r th a t it is p o ssib le to e x p la in the p a th o ­ logical differences in te rm s o f th e c o m p a ra tiv e a n a to m y o f th e k n e e jo in ts o f th e E u ro p e a n a n d the B a n tu w h ich in tu r n is a n e xpression o f th e ir e v o lu tio n from th e q u a d ru p e d a l to th e b ip ed a l fo rm o f lo c o m o tio n . It c a n n o t be em p h a sise d to o stro n g ly th a t th e differences n o te d in th e tw o races a re n o t g enetic ra cial differences in th e a n th ro lo g ic a l sense, b u t sim ply differences a cq u ired by v a ry in g a p p ro a c h e s to the fu n c tio n s a n d use o f th e knee jo in t. T h e B a n tu knee jo in t h as m a in ta in e d a m o re n a tu ra l fu n c tio n , b ecause it h a s n o t h a d to a c q u ire a d d itio n a l m o d ific atio n s w hich th e a b o v e o f th e k n e e jo in t in the w estern w orld h as ne ce ssitate d . T h e w ay we tea ch o u r ch ild ren to w alk a n d s ta n d , th e w e arin g o f shoes w ith heels, stre n u o u s g am es, g y m nastics a n d so o n , have a ll p u t a d d i­ tio n a l u n n a tu ra l stra in s o n the v a rio u s c o m p o n e n ts o f the k nee jo in t, w hich o ver m an y g e n e ra tio n s have h a d to m o d ify th e ir fu n c tio n s to c ope w ith th e new d e m a n d s. T H E D I A N N E P E A R M A N A W A R D A floating tro p h y a n d its m in ia tu re to g e th e r w ith a c ash a w a rd o f R IO .00 w ill go to th e o u ts ta n d in g S o u th A fric a n b lind physiotherapy stu d e n t e ach year. T h e D ia n n e P e a rm a n M e m o ria l A w a rd h a s been c re a te d a fte r th e tra g ic p a ssin g o f M iss D ia n n e P e a rm a n in M a rc h 1963. since M iss P e a rm a n p layed a v ery im p o rta n t p a r t in th e b u ilding u p o f th e B lind P h y s io th e ra p ists’ G ro u p , in a d d itio n to n u m e r­ ous activities in p h y sio th e ra p y as well as o th e r circles, it w as th o u g h t th a t h e r m em o ry sh o u ld live o n in th e fo rm o f a n a w a rd maf e t ° th e b e st b lin d S o u th A fric a n p h y sio th e ra p y s tu d e n t e ach year. A t p re se n t s tu d e n ts in L o n d o n have o nly been eligible h r i awarc* w as m a d e to M r. S. J a k o b s w ho h a s j u s t c o m p le te d his tra in in g in L o n d o n in 1963. A s fro m 1964 we h o p e th a t Dlind stu d e n ts tra in in g in P re to ria will a ls o be in th e selection. In a d d itio n to a c ash prize, a flo atin g tro p h y is to be pre sen te d and the w inner re ta in s a m in ia tu re tro p h y . M ay D ia n n e P e a rm a n ’s high ideals live o n in th is w ay a n d inspire a n d e n c o u ra g e new, y o u n g s tu d e n ts o f the fu tu re . R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. )