My Approach to Femoroacetabular Impingement

Transcription

1 My Approh to Femoroetulr Impingement 17 J. W. Thoms Byrd Introdution Impingement is not new onept. As erly s 1913, Vulpius nd Stöffel desried ony resetion proedure for the deformity reted y slipped pitl femorl epiphysis [ 1 ]. In 1936, Smith-Petersen desried n opertion with exision of the etulr rim sometimes omined with wedge resetion of the femorl hed/nek juntion for ses of protrusio, slipped epiphysis, nd ox pln [ 2 ]. Although primitive, the tehnique ers striking similrity to the reent desriptions of open surgil dislotion for piner nd m impingement. This omined pproh reeived no further mention in the literture, ut osteoplsty for the femorl deformity ssoited with hroni slipped pitl femorl epiphysis ws populrized y Heymn nd Herndon nd hs similrly een desried for the misshpen femorl hed of ox pln s sequel of Perthes disese [ 3, 4 ]. However, it ws Professor Gnz nd ollegues who formulted the onept of femoroetulr impingement (FAI). This ws fi rst desried s n itrogeni proess ssoited with overorretion of perietulr osteotomy (PAO) performed for dysplsi [ 5 ]. Susequently, they desried FAI ourring in the ntive hip s preursor to the development of osteorthritis [ 6 ]. They sugrouped this into piner, m, nd omined types nd desried n open surgil pproh for orretion [ 7 ]. Suessful reports hve een pulished with gol of delying the progression of osteorthritis, ut this hs not een tehnique dvoted for the resumption of n tive lifestyle [ 8 ]. It is our perspetive tht FAI is not use of hip pin. It is simply morphologi vrint tht predisposes the joint to intr-rtiulr pthology tht then eomes symptomti. Piner impingement, used y n overhnging of the nterolterl rim of the etulum, results primrily in J. W. T. Byrd, M.D. Nshville Sports Mediine Foundtion, 2011 Churh Street, Suite 100, Nshville, TN 37203, USA e-mil: yrd@nsmfoundtion.org rekdown of the etulr lrum nd seondrily, over time, vrile mount of ssoited rtiulr dmge to the etulum (Fig ). Cm impingement, reted y the prominent portion of nonspheril femorl hed engging ginst the rtiulr surfe of the etulum, results in seletive delmintion nd filure of the rtiulr surfe of the etulum with reltive preservtion of the lrum (Fig ). These oservtions re importnt in the Norml Lrum Piner impingement Fig ( ) Bony over-overge of the nterior lrum sets the stge for piner impingement. ( ) With hip flexion, the nterior lrum gets rushed y the piner lesion ginst the nek of the femur. Seondry rtiulr filure ours over time. In the norml irumstne, there is dequte lerne for the lrum during hip flexion. (All rights re retined y Dr. Byrd) J.W.T. Byrd (ed.), Opertive Hip Arthrosopy, DOI / _17, Springer Siene+Business Medi New York

2 216 J.W.T. Byrd Norml Cm impingement Lrum Aetulr rtilge Fig The impingement test is performed y provoking pin with fl exion, ddution, nd internl rottion of the symptomti hip. (All rights re retined y Dr. Byrd) Fig ( ) The m lesion is hrterized y the ony prominene entered on the nterolterl femorl hed/nek juntion. ( ) Cm impingement ours with hip fl exion s the nonspheril portion of the femorl hed (m lesion) glides under the lrum engging the edge of the rtiulr rtilge nd results in progressive delmintion. Initilly, the lrum is reltively preserved, ut seondry filure ours over time. (All rights re retined y Dr. Byrd) proposed rthrosopi mngement of FAI. Hips my possess the morphologi fetures of FAI without developing the rtilge filure ssoited with pthologil impingement. Thus, the rthrosopi fi ndings re determinnt in the ourse of mngement for ptients who possess rdiogrphi fetures of FAI. Impingement is not the sole use of intr-rtiulr pthology nd hip joint symptoms in tive dults. Ptient Evlution T h e o n s e t o f s y m p t o m s s s o i t e d w i t h FA I i s v r i l e, u t the dmge results from the umultive effet of ylil norml wer ssoited with the ltered joint morphology. Exmintion will usully demonstrte diminished internl rottion used y the ltered ony rhiteture of the joint. However, mny ptients my hve redued internl rottion nd still not suffer from pthologil impingement. Also, while unommon, pthologil impingement is osionlly oserved in individuls with norml or even inresed internl rottion. Fored fl exion, ddution nd internl rottion, is lled the impingement test in referene to eliiting symptoms ssoited with impingement (Fig ). However, virtully ny irritle hip, regrdless of the etiology, will e unomfortle with this mneuver. Thus, while it is quite sensitive, it is not neessrily spei fi for impingement. Athleti pulgi my mimi or oexist with FAI nd neessittes reful evlution of the lower dominl nd ddutor region (Fig ). Te n d e r n e s s w i t h r e s i s t e d s i t - u p s, hip fl exion, or ddution should rise n index of suspiion for thleti pulgi. Pin with pssive fl exion nd internl rottion is more inditive of n intr-rtiulr soure. Imging R d i o g r p h s s h o u l d i n l u d e w e l l - e n t e r e d A P p e l v i s v i ew nd lterl view of the ffeted hip (Fig ) [ 9, 10 ]. Overoverge of the nterior etulum, hrteristi of piner impingement, is evluted y the presene of rossover sign (Fig ). T h i s n e d u e t o e t u l r r e t r ove r- sion, indited y the posterior wll sign (Fig ). T h e lterl enter edge (CE) ngle of Wierg ws desried to quntify dysplsi whih is vriously de fi ned s less thn mong different reports. No true mesure for impingement hs een de fi ned, ut it is generlly ssoited with higher CE ngles. Dysplsi n sometimes oexist with etulr retroversion, nd trimming the etulr rim would e ontrindited (Fig ). Fo r s o m e s e s, flse pro fi le view n e helpful to further ssess etulr over- or underoverge. The spheriity of the femorl hed is ssessed on oth the AP nd the lterl views (Fig ). We tend to rely on frog lterl view s routine sreening rdiogrph. It is esy to otin in reproduile fshion.

3 17 My Approh to Femoroetulr Impingement 217 d Fig ( ) Creful plption ids in ssessing for the presene of soft tissue pelvi pthology. ( ) Hip fl exor soreness is eliited y plption during resisted ontrtion. ( ) Tenderness is eliited t the origin of the ddutors y plption during resisted ontrtion. ( d ) The insertion of the retus dominis is plpted for tenderness during resisted ontrtion. Counterpressure is pplied to the ontrlterl shoulder using seletive reruitment nd ontrtion of the involved side. (All rights re retined y Dr. Byrd) One study showed tht the 40 Dunn view most preditly d e m o n s t r t e s t h e m l e s i o n [ 11 ]. H ow eve r, e u s e o f t h e vrile shpe nd lotion of the lesion, no rdiogrph is onsistently relile. Mgneti resonne imging (MRI) nd gdolinium rthrogrphy with MRI (MRA) n oth e helpful t deteting the intr-rtiulr dmge ompnying FAI. These studies re est t de fi ning lrl pthology ut re less relile in ssessing the ssoited rtiulr dmge [ 12 ]. I n t h e p r e s e n e o f m l e s i o n, n t i i p t e t h t the rtiulr dmge will e more extensive thn the lrl pthology. Also, suhondrl edem in the nterior etulum is usully hringer of sujent rtiulr filure. With MRAs, the injetion of long-ting nestheti long with the ontrst is importnt to sustntite whether the hip disese is the soure of the ptient s symptoms. This distintion my not lwys e ler on linil exmintion lone. Computed tomogrphy (CT) is muh etter t showing one rhiteture nd struture. Three-dimensionl reonstrutions provide the lerest imge of the impingement m o r p h o l o g y. T h e s e i m g e s r e e s p e i l l y h e l p f u l i n t h e rthrosopi mngement, providing ler interprettion of the ext shpe of the norml one tht must e exposed nd then reseted. Arthrosopi Proedure (See Video 17.1: ) Arthrosopi mngement of FAI egins with rthrosopy of the entrl omprtment. This is where the intr-rtiulr dmge, inditive of pthologil impingement, is identi fi ed. The ptient is positioned supine with trtion pplied, nd three stndrd portls provide optiml ess for surveying nd essing intr-rtiulr pthology (Fig , ) [ 13, 14 ]. Portl plement is usully routine. However, severe impingement ses with tight psule nd ltered ony rhiteture n introdue signi fi nt hllenges. It is importnt tht the surgeon e prepred for these hllenges in order to perform the

4 218 J.W.T. Byrd Fig A properly entered AP rdiogrph must e ontrolled for rottion nd tilt. Proper rottion is on fi rmed y lignment of the oyx over the symphysis pui ( vertil line ). Proper tilt is ontrolled y mintining the distne etween the tip of the oyx nd the superior order o f the symphysis puis t 1 2 m. (All rights re retined y Dr. Byrd) Fig AP view of the right hip. Aetulr retroversion s use of piner impingement is indited y shllow posterior wll in whih the posterior rim of the etulum ( lk dots ) lies medil to the enter of rottion of the femorl hed ( white dot ). (All rights re retined y Dr. Byrd) Fig AP view of the right hip. The nterior ( white dots ) nd posterior ( lk dots ) rim of the etulum re mrked. The superior portion of the nterior rim lies lterl to the posterior rim ( white rrow ) inditing overoverge of the etulum. Anteriorly, it ssumes more norml medil position, reting the rossover sign ( lk rrow ) s positive inditor of piner impingement. (All rights re retined y Dr. Byrd) proedure s trumtilly s possile. Unique hllenges of the stiff nd rthro fi rosed hip re disussed in Chp. 27. There re three rthrosopi prmeters of piner impingement. First is the presene of nterior lrl pthology tht must e present in order to hve pthologil piner impingement. Seond, positioning of the nterior portl my e dif fi ult despite dequte distrtion, nd this is due to the ony prominene of the nterolterl etulum. Third is the presene of one overhnging the lrum where normlly there would just e psulr re fl etion when piner impingement is not present. The mount of one to e removed is determined in onjuntion with the rdiogrphi nd rthrosopi fi ndings. In determining whether to exise one, the rdiogrphs should e refully ssessed for evidene of dysplsi. Retroversion in dysplsti hip n give flse sense of piner impingement. Reontouring the etulum in this setting n result in itrogeni instility. If the lrum ppers norml, we would e hesitnt to violte helthy tissue to orret piner lesion euse of the theory tht it ould e prolem (Video 17.2: goo.gl/dxws7 ). A norml lrum will never look the sme

5 17 My Approh to Femoroetulr Impingement 219 Fig AP rdiogrph of the left hip of 24-yer-old femle demonstrtes etulr retroversion (rossover sign) in onjuntion with dysplsi (CE ngle 19 ). Misinterpreting this s n impingement prolem nd trimming the etulum would ple the ptient t high risk of instility. (All rights re retined y Dr. Byrd) when it is restored. Assessing dmged lrum is usully strightforwrd. However, ssessing impending lrl filure n e more sujetive. This is espeilly importnt in younger ptients. If the lrum is strting to pper rushed nd drped ross ony prominene of the etulr rim, then it is preferle not to wit until it is severely dmged to mke the hoie of orreting the ompnying piner impingement (Video 17.3: ). Deiding how norml is norml enough to mke this deision n sometimes e hllenging. If lrl degenertion is extensive, s is often seen in middle ge, then it my e mnged with simple deridement (Video 17.4: h t t p : / / g o o. g l / r 9 d x f ). The lrl dmge my not e slvged, ut reontouring the etulum opens the joint nd my sustntilly improve moility nd symptoms. After ompletely inspeting the joint, ttention is turned to the lrl lesion. Seletive deridement of the dmged portion will revel the overhnging lip of one insted of the norml psulr re fl etion from the lrum (Fig e ). One the dmged tissue hs een removed, Fig A frog lterl view of the right hip. ( ) The m lesion ( rrow ) is evident s the onvex normlity t the hed/nek juntion where there should normlly e onve slope of the femorl nek. ( ) The lph ngle is used to quntitte the severity of the m lesion. A irle is pled over the femorl hed. The lph ngle is formed y line long the xis of the femorl nek (1) nd line (2) from the enter of the femorl hed to the point where the hed diverges outside of the irle ( rrow ). (All rights re retined y Dr. Byrd) exposing the piner lesion, the one is then reontoured with spheril urr. Generous psulotomies round the portls filitte mneuverility nd ess. The piner lesion is ddressed swithing the rthrosope nd instrumenttion etween the nterior nd nterolterl portls. Resetion is typilly rried to the rtiulr edge of the etulum. The mount of one to e removed is ditted y the severity of the piner lesion. Proximlly, the one is reseted fl ush with the nterior olumn of the etulum. The nteromedil nd lterl extent of the ony resetion is ditted y the mrgin of helthy lrum. The one is reontoured to rete smooth trnsition with the helthy portion of the lrum, whih is preserved. A vrile mount of ssoited seondry rtiulr dmge my e present whih is ddressed with hondroplsty or mirofrture for grde IV lesions.

6 220 J.W.T. Byrd Fig ( ) The site of the nterior portl oinides with the intersetion of sgittl line drwn distlly from the nterior superior ili spine nd trnsverse line ross the superior mrgin of the greter trohnter. The diretion of this portl ourses pproximtely 45 ephld nd 30 towrd the midline. The nterolterl nd posterolterl portls re positioned diretly over the superior spet of the trohnter t its nterior nd posterior orders. ( ) The reltionship of the mjor neurovsulr strutures to the three stndrd portls is illustrted. The femorl rtery nd nerve lie well medil to the nterior portl. The siti nerve lies posterior to the posterolterl portl. The lterl femorl utneous nerve lies lose to the nterior portl. Injury to this struture is voided y using proper portl plement. The nterolterl portl is estlished fi rst euse it lies most entrlly in the sfe zone for rthrosopy. (All rights re retined y Dr. Byrd)

7 17 My Approh to Femoroetulr Impingement 221 d e Fig A 38-yer-old femle with progressive pin nd loss of motion of the right hip. ( ) A 3D CT sn illustrtes piner impingement ( rrows ) s well s kissing lesion hrterized y osteophyte formtion on the femorl hed ( sterisk ). ( ) Viewing nteriorly from the nterolterl portl, there is mertion of the nterior lrum ( white sterisk ) nd some ssoited rtiulr delmintion ( lk sterisk ). ( ) Deridement of the degenerte lrum exposes the piner lesion ( rrows ). ( d ) The piner lesion is reontoured with urr. ( e ) A postopertive 3D CT sn demonstrtes the extent of ony reontouring of the etulum nd the femorl hed. (All rights re retined y Dr. Byrd)

8 222 J.W.T. Byrd Fig A piner lesion reted y n os etulum long the nterolterl rim of right hip. ( ) The frgment is exposed. ( ) The frgment is eing removed. ( ) The integrity of the lrum hs een preserved. (All rights re retined y Dr. Byrd) In the presene of good qulity lrl tissue nd espeilly in younger ptients, preservtion of the lrum is preferred. In few ses, the ony lesion n e exposed on the psulr side of the lrum nd reontoured without ompromising the lrum s struturl integrity (Fig ) (Video 17.5: h t t p : / / g o o. g l / 2 U p ). More often, when the lrum is filing due to piner impingement, it is moilized to reset the piner lesion nd then re fi xed (Fig ). The portion of the lrum to e moilized must e exposed t its ony tthment on the psulr side. The lrum is shrply disseted from the overlying one to revel the piner lesion. The etulum is then reontoured with high-speed urr, tking re to preserve the moilized lrum. With this tehnique, dequte moiliztion of the lrum is neessry to visulize the ony mrgins of the piner lesion for reontouring. Indequte exposure results in simply smll slloped defet in the etulr rim with inomplete orretion. The depth of resetion is typilly 3 5 mm ut is determined y the dimensions of the piner lesion. Resetion of the ony rim requires good rthrosopi visuliztion. Do not rely solely on fl uorosopy euse it will use you to underestimte the mount of one eing removed nterior to the 12 o lok position. After reshping the rim, the lrum is then re fi xed with suture nhors. The nhors re pled in the rim of the etulum on the psulr side of the lrum. The nhor plement is onsistent from one se to the next. The nhors re sped pproximtely 8 10 mm nd s lose to the rim s possile while ssuring tht they do not perforte the surfe of the etulum. For this purpose, we use perutneous delivery system tht llows the skin entry site of the drill sleeve to e pled s distlly s neessry to mke sure tht the nhor diverges from the etulr surfe. This is pled distlly, hlfwy etween the nterior nd nterolterl portls (Fig ). T h e m o d i fi e d n t e - rior portl, tht is sometimes populr, my not lwys e distl enough to ssure the orret mount of diversion [ 15 ]. However, there is lso urved drill guide system tht n give etter ngle for this portl (Fig ). Either wy, it is impertive tht the rtiulr surfe is visulized while drilling. Any evidene of rippling of the rtilge indites tht the drill is too lose, nd it must e repositioned (Video 17.6: h t t p : / / g o o. g l / 4 L K K p ). T h e m o s t o m - mon error is not llowing enough divergene, whih fores the drill hole to e pled further wy from the rim of the etulum in order to void perfortion. Then, when the lrum is tied down, it is not properly repproximted to the rim, nd its funtion hs not een restored. With the distl perutneous site hlfwy etween the nterior nd nterolterl portls, or with the use of the modi fi ed nterior portl, nhors n e pled long the nterior etulum up to the 12 o lok position. Note tht fl uorosopy is not very helpful euse the diretion of entry is more in

9 17 My Approh to Femoroetulr Impingement 223 d Fig A 15-yer-old femle gymnst with pin nd redued internl rottion of the left hip. ( ) A 3D CT sn de fi nes piner lesion with ompnying os etulum ( rrow ) nd m lesion ( sterisk ). ( ) Viewing from the nterolterl portl, the piner lesion nd os etulum ( sterisk ) re exposed with the lrum eing shrply relesed with n rthrosopi knife. ( ) The etulr frgment hs een removed nd the rim trimmed with nhors pled to repir the lrum. ( d ) The lrum hs een re fi xed. (All rights re retined y Dr. Byrd) the plne of the x-ry em (Fig ). Fr lterl nhors re est pled from the nterolterl portl, nd for these, fl uorosopy n e helpful in seeing tht the drill is diverging from the suhondrl surfe (Fig ). While nhor plement is onsistent, the pttern nd method of suture pssge is vrile depending on the dmge nd morphology of the lrum. If the hondrolrl juntion is intt, then simple suture pssge is used through the midsustne of the lrum nd tied ginst the psulr side. This reonstitutes the lrum ginst the rim well. The suture n e pssed through the lrum with tissue-penetrting devie, or if the lrum is smll, then suture shuttle tehnique llows the smllest possile hole in the lrl tissue (Fig ). If the lrum is roust, then simple suture tehnique my distort its on fi gurtion, or if the rtiulr edge of the lrum hs een seprted from the djent rtiulr surfe, then different type suture must e used to reonstitute the hondrolrl juntion. For this, modi fi ed single lim mttress suture is used (Fig ) ( Vi d e o : h t t p : / / g o o. g l / GS58 ). One lim of the suture is pssed into the joint t the hondrolrl juntion, using tissue-penetrting devie. It is then grsped through the midportion of the lrum nd pulled out for tying ginst the psulr edge.

10 224 J.W.T. Byrd Fig An nhor delivery system n e pled perutneously nd thus not depend on portls. Pled midwy etween the nterior nd nterolterl portls, it is positioned s distlly s neessry to ssure tht the nhors will diverge from the fe of the etulum. ( ) Prepositioning is performed with spinl needle. ( ) The nhor delivery system hs een perutneously pled. ( ) Shemti illustrtes the drill sleeve pled ginst the etulr rim. (All rights re retined y Dr. Byrd) This ntomilly restores the lrum to the rim of the etulum nd voids distortion. If the qulity of the lrl tissue is poor, then simply looping the suture round the lrum my e neessry in order to ssure tht suf fi ient tissue hs een repproximted. Mngement of m impingement lso egins with rthrosopy of the entrl omprtment to ssess for the pthology ssoited with m lesion [ 16 ]. The hrteristi feture of pthologil m impingement is rtiulr filure of the nterolterl etulum. The femorl hed remins well preserved until lte in the disese ourse. Erly stges of the disese re hrterized y losed grde I hondrl listering, whih sometimes must e distinguished from norml rtiulr softening (Video 17.8: s10ws ). Our experiene hs een tht most lredy hve grde III or grde IV etulr hnges y the time of surgil intervention. The rtiulr surfe is seen to seprte or peel wy from its tthment to the lrum (Fig ), nd this is used y the sher effet of the m lesion (Video 17.9: ). The lrum my e reltively

11 17 My Approh to Femoroetulr Impingement 225 Fig Fluorosopi imge of right hip drilling for plement of n nhor in the nterior rim of the etulum ( rrow ). Fluorosopy does not help in ssessing the nhor position. (All rights re retined y Dr. Byrd) Fig ( ) A urved nhor delivery system provides more ltitude for ssuring divergene when the nhor is pled through onventionl portl. ( ) The urved system is pled ginst the etulr rim from the modi fi ed nterior portl in this right hip with pproprite divergene for the etulr surfe. (All rights re retined y Dr. Byrd) well preserved ut, with time, progressive frgmenttion ours. Often, the dmged rtiulr edge of the lrum n e seletively derided, preserving the psulr mrgin nd potentilly some of its lrl sel funtion. If there is good qulity tissue tht hs een dethed, repir n e performed with suture nhors (Fig ). If piner impingement is not present, the nhors n e pled djent to the rtiulr surfe, etween the etulum nd the lrum (Video 17.10: ). The suture lims n e grsped through the lrum with penetrtor devie nd tied with the knots on the psulr side of the lrum. Pssing oth lims of the suture in mttress fshion voids suture ruing ginst the femorl hed, ut osionlly, looping the sutures my e neessry to ssure tht good sustne of the tissue is seured to the rim of the etulum. The rtiulr pthology is ddressed with hondroplsty nd mirofrture s ditted y its severity. Fig AP fl uorosopi imge of right hip drilling for n nhor in the lterl etulum ( rrow ). From this ngle, the imge helps to ssure tht the drill does not violte the suhondrl surfe. (All rights re retined y Dr. Byrd) After ompleting rthrosopy of the entrl omprtment, the m lesion is ddressed from the peripherl omprtment. A psulotomy is reted y onneting the nterior nd nterolterl portls (Fig ). The mount of

12 226 J.W.T. Byrd d Fig Arthrosopi view of right hip. Aetuloplsty hs een ompleted, nd the nhor hs een seted in the nterior etulum. The hondrolrl juntion is preserved. ( ) A soft tissue-penetrting devie is used to push the suture lim through the lrum. ( ) As n lterntive method, suture pssing devie is pled to introdue mono fi lment suture. ( ) The rided nhor suture is then shuttled through the lrum, seured to the mono fi lment with single hlfhith. ( d ) Three nhors hve een pled with sutures tied, repproximting the lrum to the rim of the etulum. (All rights re retined y Dr. Byrd) psulotomy is titrted to the spei fi s of the se. For tight hip with restrited rottionl motion, the psulotomy eomes more of n ggressive psuletomy, whih is prtly therpeuti in helping to regin etter moility s well s pin relief. It my e extended posterolterlly nd nteromedilly. For hips where instility my e onern, the psulotomy n e limited to simply onneting the two portls with n inision of only m. This my e neessry, for exmple, in hip where dysplsi oexists with m lesion. By titrting the psulotomy to the needs of the se, psulr repir hs rrely een neessry in our experiene. If more exposure is needed in hip tht might e suseptile to instility, then vertil T-shped psulotomy n e extended distlly. The fl ps re preserved, nd the vertil lim n e repproximted t the ompletion of the proedure. After prepring the psulotomy, the posterolterl portl n e removed, nd the nterior nd nterolterl nnuls re simply ked out of the entrl omprtment. The trtion is relesed, nd the hip fl exed pproximtely 35. As

13 17 My Approh to Femoroetulr Impingement 227 Fig Arthrosopi view of right hip from the nterolterl portl. ( ) The lrum is roust with disruption of the hondrolrl juntion. ( ) Viewing peripherl to the lrum, the etuloplsty ( sterisk ) hs een ompleted. ( ) A suture nhor hs een seted in the ony rim nd one lim of the suture is grsped with soft tissue-penetrting devie. ( d ) With the penetrtor, the suture hs een pssed into the joint t the hondrolrl juntion. ( e ) The penetrtor hs een repositioned through the midsustne of the lrum, prepring to grsp the suture lim. ( f ) The suture hs een grsped nd is withdrwn k out to the psulr rim. ( g ) Three nhors hve een pled with sutures tied, restoring the lrum nd the hondrolrl juntion. ( h ) Lrl restortion is further oserved peripherlly with reonstitution of the lrl sel. (All rights re retined y Dr. Byrd) d e f g h

14 228 J.W.T. Byrd Fig A 20-yer-old hokey plyer with 4-yer history of right hip pin. ( ) A 3D CT sn de fi nes the m lesion ( rrows ). ( ) Viewing from the nterolterl portl, the proe introdued nteriorly disples n re of rtiulr delmintion from the nterolterl etulum hrteristi of the peel-k phenomenon reted y the ony lesion shering the rtiulr surfe during hip fl exion. (All rights re retined y Dr. Byrd) the hip is fl exed under rthrosopi visuliztion, the line of demrtion etween helthy femorl rtilge nd norml fi rortilge tht overs the m lesion n usully e identi fi ed. Flexing the hip too fr n use prt of the m lesion to dispper under the etulum. In generl, slightly more or less fl exion my e neessry, just depending on the position tht est rings the m lesion into view. A ephld nterolterl portl is estlished pproximtely 5 m ove the nterolterl portl, entering through the psulotomy tht hs lredy een estlished. These proximl nd distl nterolterl portls work well for essing nd ddressing the m lesion (Fig ). Removing the nterior portl provides n unostruted imge for the C-rm, lthough the portl n e mintined if it is needed for etter ess to the medil side of the femorl nek. Most of the work for performing the reontouring of the m lesion (femoroplsty) lies in the soft tissue preprtion. This inludes psulr resetion s neessry to ssure omplete visuliztion of the lesion nd then removl of the fi rortilge nd sr tht overs the norml one (Fig ). With the hip fl exed, the proximl portl provides etter ess for the lterl nd posterior portion, while the distl portl is more nterior reltive to the joint nd provides est ess for the nterior prt of the lesion. The lterl synovil fold is identi fi ed s the rthrosopi lndmrk for the retinulr vessels, nd re is tken to preserve this struture during the reontouring (Fig ). Swithing etween the portls is importnt for full ppreition of the three-dimensionl ntomy of the reontouring. One the one hs een fully exposed, reontouring is performed with spheril urr. The gol is to remove the norml one identi fi ed on the preopertive CT sn nd rerete the norml onve reltionship tht should exist where the femorl nek meets the rtiulr edge of the femorl hed. It is est to egin y reting the line nd depth of resetion t the rtiulr mrgin. The resetion is then extended distlly, tpering with the norml portion of the femorl hed (Figs , nd 17.27, ). We reommend eginning the resetion t the lterl/posterior limit of the m lesion with the rthrosope in the more distl portl nd instrumenttion in the more proximl portl. The posterior extent of the resetion is usully the most dif fi ult; the resetion is lso the most ritil to void nothing the tensile surfe of the femorl nek, nd prtiulr ttention must e given to void nd preserve the lterl retinulr vessels. Then, swithing the rthrosope to the proximl portl, the

15 17 My Approh to Femoroetulr Impingement 229 d e Fig An nterior lrl ter of right hip is eing viewed from the nterolterl portl. ( ) Pthologil dethment of the lrum from the rim of the etulum is eing proed. ( ) Freshening the rim of the etulum, reting leeding ony surfe, ids in potentiting heling of the repir. ( ) Two nhors hve een pled in the rim of the etulum with the sutures pssed through the lrum in mttress fshion. ( d ) The sutures hve een tied seurely repproximting the lrum to the rim of the etulum. ( e ) Now viewing from the peripherl omprtment, the repir is inspeted showing pproximtion of the lrum ginst the femorl hed with the sutures well removed from the rtiulr surfe. (All rights re retined y Dr. Byrd)

16 230 J.W.T. Byrd Fig A psulotomy is performed y onneting the nterior nd nterolterl portls ( dotted line ). This is geogrphilly loted djent to the re of the m lesion. This psulotomy is neessry in order for the instruments to pss freely from the entrl to the peripherl omprtment s the trtion is relesed nd the hip fl exed. (All rights re retined y Dr. Byrd) urr is introdued distlly, nd the reshping is ompleted long the nterior hed nd nek juntion. Lstly, ttention is given to mke sure tht ll one deris is removed s thoroughly s possile to lessen the likelihood of developing heterotopi ossi fi tion. The qulity of the reontouring is ssessed, nd preservtion of the lterl retinulr vessels is on fi rmed (Fig ). Closure of the psulotomy is not routinely performed. In ses where instility might e potentil onern, T-shped psulotomy is used, nd the vertil lim n e losed with single interrupted rided sorle sutures (Fig d ). Comments on Determining the Corret Amount of Bone to Remove Wi t h p r o p e r ex p o s u r e n d m e t i u l o u s t e h n i q u e, t h e e n t i r e t y of the ony impingement n e identi fi ed for preise resetion. Wht is less ler is knowing the ext mount of one to remove. Presently, 3D CT sns provide the lerest imge of the ony lesion. Thus, we use this s the prinipl determinnt for interpreting the one to e removed. The gol is not so muh to rerete stndrd-looking hip ut to Fig ( ) With the hip fl exed, the nterolterl portl is now positioned long the nek of the femur. A ephld (proximl) nterolterl portl hs een pled. These two portls llow ess to the entirety of the m lesion in most ses. Their position lso llows n unhindered view with the C-rm. ( ) Photogrph illustrtes the proximl nd distl nterolterl working portls for the peripherl omprtment. (All rights re retined y Dr. Byrd) remove the offending one nd, on the femorl side, rerete the norml onvity tht should exist t the hed/nek juntion. In the ner future, omputer nvigtion will ssist in urtely quntitting the mount of removl tht must now e done y sujetive interprettion. This will e performed with 3D MRI tht will supplnt omputed tomogrphy. For the present, one must e utious out relying muh on intropertive fl uorosopy. The line of resetion

17 17 My Approh to Femoroetulr Impingement does not prllel the x-ry em, nd thus, it is esy to go stry relying solely on fl uorosopy. We fi nd fl uorosopy most helpful in ssessing the posterior limit of the resetion. Sometimes the lterl spet of the m lesion strts to dispper underneth the posterior etulr rim. Fluorosopy n e helpful to mke sure tht dequte proximl resetion hs een performed. In some ses, rie fl y repplying trtion my e helpful to fully ess this posterior limit. Intropertive rnge of motion is not sustitute for omplete visuliztion of the norml one. Our gol is, gin, to remove the norml one nd rerete the norml onvity. One this hs een omplished, it is unlikely tht greter resetion would e of more ene fi t. It is lso unler how well pssive rnge of motion of n nesthetized ptient with joint distended with fl uid equtes with how the ptient s hip funtions in vivo. Post-op Rehilittion The reovery strtegy depends on the extent of pthology tht is enountered t the time of rthrosopy nd wht is done to ddress it. For simple lrl deridement nd reontouring of the etulr rim, the ptient is llowed to weight er s tolerted, with n emphsis on rnge of motion nd joint stiliztion. If the lrum is re fi xed, then preutions re neessry to protet the repir site during the erly heling phse. This inludes proteted weight ering nd voiding extremes of fl exion nd externl rottion for the fi rst 4 weeks. Among ptients requiring seond-look rthrosopi proedure, rrely is filure of lrl repir found to e prolem. Thus, our reh strtegy proteting the repir site my still e too onservtive when we need to emphsize prevention of dhesions, ut we re still reful not to e too ggressive. Reshping of the femorl hed/nek juntion neessittes some preutions. Frture of the femorl nek is n unlikely, ut potentilly serious, omplition. Full weight ering is llowed, ut ruthes re used to void wkwrd twisting movements during the fi rst 4 weeks. One full motor ontrol hs een regined, the joint is dequtely proteted for light tivities. If osteopeni is present, then these preutions eome more impertive, espeilly in postmenopusl women nd ny ptient over the ge of 55. Full ony remodeling tkes 3 months, during whih time, some preutions re neessry to void high impt or torsionl fores. If mirofrture is performed, strit proteted weight ering is ontinued for 2 months to optimize the erly mturtion of the fi rortilginous heling response. During this time, gentle rnge of motion is emphsized to stimulte the heling proess. 231 At 3 months, spei fi preutions re lifted, nd funtionl progression is llowed. The rte t whih the individuls dvne is vrile nd my require nother 1 3 months for full tivities. Athletes re generlly dvised tht return to sports following surgil orretion of FAI n tke 4 6 months. Results We h ve p u l i s h e d t wo s t u d i e s r e p o r t i n g t h e o u t o m e s o f our erliest experiene in rthrosopi mngement of FAI [ 17, 18 ]. I n s t u d y o f o u r fi r s t o n s e u t ive p t i e n t s w i t h minimum 2-yer follow-up, the medin improvement ws 21.5 points using the modi fi ed Hrris hip sore with 79% good nd exellent results [ 17 ]. N i n e t y - t wo p e r e n t h d grde III or grde IV etulr rtiulr dmge, inluding 18 ptients who underwent mirofrture with medin improvement of 21 points. Twenty-three ptients hd onomitnt rtiulr dmge to the femorl hed demonstrting slightly lesser improvement of 17 points. No ptient required onversion to totl hip rthroplsty, lthough six underwent susequent rthrosopi proedure for reurrent or persistent symptoms. There were three omplitions: trnsient neurprxi of the pudendl nerve nd the lterl femorl utneous nerve, oth of whih resolved uneventfully, nd one mild se of heterotopi ossi fi tion within the psule whih did not prelude suessful outome. In nother study of our fi rst 200 onseutive thletes with minimum 1-yer follow-up, the medin improvement ws 24 points. Eighty-nine perent hd grde III or grde IV rtiulr dmge with 49 undergoing mirofrture nd demonstrting medin improvement of 26 points [ 18 ]. Tw e n t y perent hd onomitnt rtiulr dmge to the femorl hed nd demonstrted lesser improvement of 16 points. Overll, 90% returned to sport (95% professionl, 85% ollegite). There were fi ve trnsient neurprxis tht resolved. One thlete ws onverted to totl hip rthroplsty nd four underwent repet rthrosopy. T h e r e s u l t s o f o u r e r l i e s t ex p e r i e n e s s e e m g o o d, eve n though most of these inluded lrl deridements. As we hve reognized the heling pity of the lrum nd suessful tehniques for repir, the mjority of ptients now undergo lrl repir or re fi xtion. As evidened y the work of others, it does pper tht this my provide even more fvorle results [ 19, 20 ]. O u r o s e r v t i o n h s e e n tht high mjority of ptients hve grde III or grde IV rtiulr dmge to the etulum y the time rthrosopi intervention is undertken. Despite the severity of dmge, our results re still good. This indites tht grde III nd grde IV dmge is not ontrindition to the proedure, ut it lso indites tht we re intervening lte in the

18 232 J.W.T. Byrd Fig Viewing lterlly, underneth the re of the lterl psulotomy, the lterl synovil fold ( rrows ) is identi fi ed long the lterl se of the nek, representing the rthrosopi lndmrks of the lterl retinulr vessels. (All rights re retined y Dr. Byrd) Fig The right hip is viewed from the nterolterl portl. ( ) The m lesion is identi fi ed, overed in fi rortilge ( sterisk ). ( ) An rthrosopi urette is used to denude the norml one. ( ) The re to e exised hs een fully exposed. The soft tissue preprtion ids in preisely de fi ning the mrgins to e exised. (All rights re retined y Dr. Byrd) Fig The rthrosope is in the more distl (nterolterl) portl with the instrumenttion pled from the proximl portl. ( ) Bony resetion is egun t the rtiulr mrgin. ( ) The resetion is then rried distlly, rereting the norml onve reltionship. (All rights re retined y Dr. Byrd)

19 17 My Approh to Femoroetulr Impingement 233 Fig The rthrosope is now in the proximl portl with the instrumenttion introdued distlly. ( ) The line of resetion is ontinued long the nterior rtiulr order of the ump. ( ) The reontouring is ompleted. (All rights re retined y Dr. Byrd) Fig The rthrosope hs een returned to the distl portl for fi nl survey, ( ) viewing medilly; ( ) viewing lterlly; ( ) on fi rming preservtion of the lterl retinulr vessels ( rrows ). (All rights re retined y Dr. Byrd)

20 234 J.W.T. Byrd d Fig ( ) Dunn view of the pelvis of n elite level femle hurdler with symptomti m lesion ( rrow ) in her left led leg ssoited with dysplsi (CD ngle 20 ). ( ) Viewing the left hip from the nterolterl portl, smll psulotomy hs een mde onneting the nterior nd nterolterl portls, exposing the femorl hed ( FH ). An rthrosopi knife is used to rete vertil T-lim to the psulotomy to expose the m lesion. ( ) The m lesion hs een orreted ( sterisk ) rereting the norml onvity of the hed/nek juntion. ( d ) Sme view with the vertil lim of the psulotomy repproximted with interrupted rided sorle sutures. (All rights re retined y Dr. Byrd) d i s e s e o u r s e. T h u s, w e n e e d t o lern how to detet nd properly selet ptients for erlier intervention. Of ourse, we would not reommend surgery in someone who is symptomti, ut ptients who re minimlly symptomti should e eduted on wrning signs of progressive dmge tht might neessitte protive pproh. Mirofrture is perhps n imperfet solution for full-thikness rtiulr loss, ut our results hve still een quite fvorle. With FAI, the rtiulr surfe of the femorl hed tends to remin well preserved until very lte in the disese ourse. Our oservtion is tht one the femorl surfe strts to fil, the results, lthough fvorle, re not s good. In ft, for ses with mixed fi ndings of impingement nd dysplsi, the rthrosopi fi ndings my id in determining the prinipl ulprit. With impingement, the femorl surfe will remin well preserved despite dvned etulr hnges while, with dysplsi, rtiulr erosion is more eqully distriuted to oth surfes. Among thletes, 95% returned to sport t the professionl level nd 85% t the ollegite level. It is unlikely tht this differene indites tht we were doing etter surgil proedure mong the professionl thletes ut indites the relity tht there re numerous other ftors eyond just the surgil proedure itself tht n in fl uene suessful outomes. Our very low rte of onversion to

21 17 My Approh to Femoroetulr Impingement totl hip rthroplsty seems to indite tht we re doing good jo properly seleting ptients who re potentilly ndidtes for rthrosopi orretion of FAI, ut our modest reopertion rte indites tht we ould lso e doing etter jo with the tehnil spets of the proedure. We onur with others tht grde III Tonnis hnges re ontrindition to surgil orretion of FAI. However, grde II hnges re less ler. By de fi nition, severe m lesion ful fi lls the riteri for grde II Tonnis. Mny ptients with grde II hnges do well while others do not. In our opinion, this re fl ets tht grde II Tonnis enompsses rod spetrum of disese nd re fl ets the indequies of plin rdiogrphy to urtely re fl et the extent of intrrtiulr pthology. Conlusions Most ses of FAI n e mnged with rthrosopi surgery. This n e tehnilly hllenging proedure, ut these hllenges re lessened y methodil, systemti pproh to essing the joint nd ddressing the pthology. Severe protrusio nd ses tht require perietulr or proximl femorl osteotomy represent ontrinditions. The fvorle spet of the rthrosopi pproh is its less invsive nture, voiding the prolems of open surgery, hospitliztion, nd rehilittion. However, rthrosopy exposes the ptient to risks not ssoited with the open proedure. The iggest onerns re prolems ssoited with trtion, itrogeni injury to the joint, or less well-exeuted orretion of the ony ntomy. These prolems re entuted in stiffer hips. There re further steps tht n e tken to ddress these dded hllenges nd thoughtful, experiened pproh in weighing the ene fi ts of rthrosopy over n open proedure is required. Referenes 1. Vulpius O, Stöffel A. Orthopädishe Opertionslehre. Stuttgrt: F. Enke; Smith-Petersen MN. Tretment of mlum oxe senilis, old slipped upper femorl epiphysis, intrpelvi protrusion of the etulum, 235 nd ox pln y mens of etuloplsty. J Bone Joint Surg Am. 1936;18: Heymn CH, Herndon CH. Slipped femorl epiphysis with severe displement: onservtive opertive tretment. J Bone Joint Surg Am. 1957;39: Greu GJ. Surgil tretment of ox pln. J Bone Joint Surg Br. 1964;46: Myers SR, Eijer H, Gnz R. Anterior femoroetulr impingement fter perietulr osteotomy. Clin Orthop. 1999;363: Gnz R, Prvizi J, Bek M, Leunig M, Notzli H, Sieenrok KA. Femoroetulr impingement: use for osteorthritis of the hip. Clin Orthop. 2003;417: Lvigne M, Prvizi J, Bek M, Sieenrok KA, Gnz R, Leunig M. Anterior femoroetulr impingement: prt I. Tehniques of joint preserving surgery. Clin Orthop. 2004;418: Bek M, Leunig M, Prvizi J, Boutier V, Wyss D, Gnz R. Anterior femoroetulr impingement: prt II. Midterm results of surgil tretment. Clin Orthop. 2004;418: Prvizi J, Leunig M, Gnz R. Femoroetulr impingement. J Am Ad Orthop Surg. 2007;15(9): Clohisy JC, Crlisle JC, Trousdle R, et l. Rdiogrphi evlution of the hip hs limited reliility. Clin Orthop Relt Res. 2009;467: Meyer DC, Bek M, Ellis T, Gnz R, Leunig M. Comprison of six rdiogrphi projetions to ssess femorl hed/nek spheriity. Clin Orthop. 2006;445: Byrd JWT, Jones KS. Dignosti ury of linil ssessment, MRI, gdolinium MRI, nd intrrtiulr injetion in hip rthrosopy ptients. Am J Sports Med. 2004;32(7): Byrd JWT. The supine pproh. In: Byrd JWT, editor. Opertive hip rthrosopy. 2nd ed. New York: Springer; p Byrd JWT. Hip rthrosopy y the supine pproh. Instr Course Let. 2006;55: Kelly BT, Weilnd DE, Shenker ML, et l. Arthrosopi lrl repir in the hip: surgil tehnique nd review of the literture. Arthrosopy. 2005;21(12): Byrd JWT, Jones KS. Arthrosopi femoroplsty in the mngement of m-type femoroetulr impingement. Clin Orthop Relt Res. 2009;467: Epu 2008 De Byrd JWT, Jones KS. Arthrosopi mngement of femoroetulr impingement with minimum two-yer follow-up. Arthrosopy. 2011;27(10): Epu 2011 Aug Byrd JWT, Jones KS. Arthrosopi mngement of femoroetulr impingement (FAI) in thletes. Am J Sports Med. 2011;39: Lrson CM, Givens MR. Arthrosopi deridement versus re fi xtion of the etulr lrum ssoited with femoroetulr impingement. Arthrosopy. 2009;25(4): Philippon MJ, Briggs KK, Yen Y-M, Kuppersmith DA. Outomes following hip rthrosopy for femoroetulr impingement with ssoited hondrolrl dysfuntion. J Bone Joint Surg Br. 2008; 91-B:16 23.