.10 Specific frctures Foot.10.2 1 Midfoot nd forefoot Frctures of the nviculr 919 1.1 Surgicl ntomy 919 1.2 Frcture ptterns nd tretment 919 2 Frctures of the cuoid 922 2.1 Surgicl ntomy 922 2.2 Frcture ptterns nd tretment 922 3 Trsomettrsl joint injuries 922 3.1 Surgicl ntomy 922 3.2 Frcture ptterns nd ssessment 924 3.3 Preopertive plnning 924 3.4 Opertive tretment 92 3.5 Postopertive tretment 928 3. Results 928 4 Mettrsl frctures 928 4.1 Principles 928 4.2 Tretment 928 4.2.1 Single-ry frctures 4.2.2 Multiple-ry frctures 4.2.3 Unstle nd intrrticulr frctures 4.2.4 Frctures of the proximl fifth mettrsl 5 Frctures of sesmoid ones 930 Biliogrphy 931 918 PFxM2_Section II.ind 918 9/19/11 3:11:18 PM
Authors.10.2 1 1.1 Hns Zwipp, Andrew K Snds, Kj Klue Midfoot nd forefoot Frctures of the nviculr Surgicl ntomy The nviculr is prt of the Choprt s joint, which is composed of the rticulr surfces of the tlr hed nd nviculr medilly nd of the distl clcneus nd cuoid lterlly. Biomechniclly, it is prt of the medil rch of the foot nd hs five rticultions: the tlr hed proximlly (tlonviculr joint); the three cuneiforms distlly (innominte joint); the cuoid lterlly (cuonviculr joint). The medil nd plntr spects of the nviculr re supported y soft tissues including the plntr clcneonviculr ligment (spring ligment), the medil clcneonviculr ligment (ligmentum neglectum), nd especilly y the insertion of the strongest of the five rms of the tiilis posterior tendon. Lterlly it is supported y the lterl clcneonviculr ligment nd the dorsl cuonviculr ligment. The dorsl joint cpsule is reinforced y the dorsl tlonviculr ligment, prts of the deltoid ligment, nd the neglected ligment. The qudrilterl prt of the nviculr is stilized y the nviculr rm of the ifurcte ligment nd the cuolterl nviculr ligment. Pthomechniclly, the tiilis posterior tendon my vulse the tuerosity in eversion trum, or it cn ecome entrpped in frcture disloctions mking reduction difficult. Becuse of its centrl position in the foot, injuries to the nviculr re often ssocited with injuries to the rest of the Choprt joint nd/or Lisfrnc joint. These must e excluded y clinicl nd x-ry exmintion nd CT scn. 1.2 Frcture ptterns nd tretment There re three types of injury: corticl vulsions, frctures of the tuerosity, nd frctures of the ody [1]. Stress frctures re occsionlly seen in thletes. Corticl vulsion frctures re the result of twisting injury rupturing the strong tlonviculr cpsule nd the most nterior fiers of the deltoid ligment; one frgment is vulsed. Tretment consists of short leg wlking cst for weeks. If the frgment includes more thn 20% of the rticulr surfce, or if there is significnt instility seen on stress-x-ry (Fig.10.2-1 c), it should e stilized with smll screws (Fig.10.2-1d f). Tuerosity frctures re cused y n eversion injury, with the tiilis posterior tendon pulled off the nviculr tuerosity. If seen together with crush frcture of the cuoid, this injury my indicte n occult disloction or suluxtion of the midtrsl joint. Without displcement, short leg wlking cst for weeks is the pproprite tretment. With displcement (> 2 mm), the frcture is reduced nd stilized with screw or smll tension nd wire (Fig.10.2 2). Body frctures re usully ssocited with other midtrsl injuries, which must e dignosed nd treted. Only nondisplced frctures re treted using well molded short leg cst for weeks. Displced frctures of the nviculr re treted opertively with screws, plte, or smll temporry externl fixtor. Bone defects in cse of crush frctures should e filled with n utogrft (Fig.10.2-3). Stress frctures usully need compression y two or three 4.0 mm cncellous one screws nd short leg wlking cst for weeks (Fig.10.2-4). 919 PFxM2_Section II.ind 919 9/19/11 3:11:18 PM
.10 Specific frctures Foot c d e Fig.10.2-1 f f Avulsion frcture of the nviculr. c Corticl vulsion frcture of the nviculr with significnt instility. d f The lrge intrrticulr frgment ws fixed with three 2.0 mm cortex screws. K-wires hve een used to stilize the Choprt joint nd the fixtion ws protected with n externl fixtor. 920 PFxM2_Section II.ind 920 9/19/11 3:11:20 PM
.10.2 Midfoot nd forefoot Fig.10.2-2 c Nviculr tu- erosity frcture. A nviculr tuerosity frcture s prt of complex triple frcture of the Choprt joint. c Lg screw fixtion of the nviculr t 5 months () nd 1 yer (c). c Fig.10.2-3 d Complex n- viculr frcture. A multifrgmentry nviculr ody frcture. ORIF with plting of the 3 prt ody frcture nd tension nd wiring of the tuerosity frcture. c d Finl fixtion. c d Fig.10.2-4 Lg screw fixtion of nviculr stress frcture. 921 PFxM2_Section II.ind 921 9/19/11 3:11:22 PM
.10 2 2.1 Specific frctures Foot Frctures of the cuoid Surgicl ntomy The cuoid is the lterl of the two midfoot ones nd is n essentil one of the lterl column of the foot. It rticultes proximlly with the clcneus (clcneocuoidl joint); medilly with the nviculr (cuonviculr joint); medilly with the lterl cuneiform (cuocuneiform joint); distlly with the ses of the fourth nd fifth mettrsl (cuomettrsl joint). 2.2 grft, nd plcing locked plte on the lterl cuoid protects ntomicl reconstruction of the joint nd effectively restores the lterl column length. Frcture ptterns nd tretment The most common significnt injury to the cuoid one occurs s result of the nutcrcker mechnism descried y Hermel nd Gershon-Cohen [2]: In duction injuries, the cuoid is crushed etween the clcneus nd mettrsls. This is comprle to the nutcrcker frcture of the nviculr in forced dduction injuries [3]. If there is miniml impction, nonopertive mngement with elow-knee cst for weeks is pproprite. However, if there is significnt loss of length or duction mllignment of the lterl column of the foot, it is likely tht the long-term outcome will e pin nd dysfunction in the clcneocuoid joint nd/or involvement of the fiulris longus tendon. Mngement should include erly ntomicl reconstruction of the joint surfces proximlly (Fig.10.2-5) nd/or distlly s well s restortion of the length of the lterl column y ORIF. In compression frctures of the cuoid one, the intct joint surfce of the clcneus proximlly or those of the fourth nd fifth mettrsl se re considered for use s mold. Using little distrctor for reduction, filling the defects with one 3 3.1 Trsomettrsl joint injuries Surgicl ntomy The Lisfrnc re, which descries the trnsition etween the forefoot nd midfoot, is formed y the rticultions of the mettrsls with the cuneiforms nd the cuoid. Proper lignment nd stility of this group of joints is crucil for norml foot function. The medil column of the midfoot includes the three cuneiforms nd the medil three mettrsls. This column is less moile thn the lterl column nd rther serves s structurl support. The inherent stility of the trsomettrsl joint is due to the one ntomy of the keystone-like se of the second mettrsl, nd to the strong ligments etween ech trsomettrsl joint. Generlly, plntr ligments re stronger, nd the Lisfrnc ligment is the lrgest nd strongest of ll. It origintes from the plntr spect of the medil cuneiform nd inserts on the plntr spect of the se of the second mettrsl nd is the only link etween the first nd second mettrsl. The Lisfrnc ligment locks the se of the second mettrsl in plce, further limiting motion nd providing stility to this keystone structure. The lterl column, mde up of the cuoid nd the lterl two mettrsls, is more moile thn the medil column in order 922 PFxM2_Section II.ind 922 9/19/11 3:11:22 PM
.10.2 Midfoot nd forefoot Fig.10.2-5 g Frcture of the cuoid. d Impction frcture of the cuoid with duction mllignment of the lterl column. e g Cuoid plte fixtion nd one grft t the 3-month follow-up. c e d f g 923 PFxM2_Section II.ind 923 9/19/11 3:11:24 PM
.10 Specific frctures Foot to llow wlking on uneven ground. This flexiility is necessry for proper foot function. Posttrumtic instility is etter tolerted here, ut stiffness cuses significnt prolems. In reconstructing the trsomettrsl joint, it is criticl to keep these ntomicl chrcteristics in mind. Perfect ntomicl reduction is crucil for excellent long-term results [4, 5]. 3.2 Frcture ptterns nd ssessment stress views mens instility. The AP view is est suited for evluting lterl displcement of the second mettrsl on the intermedite cuneiform. The lterl order of the first cuneiform should line up with the first mettrsl se. The lterl view helps to ssess ny dorsl displcement. The olique view is optiml for ssessing lignment of the third nd fourth mettrsls with the lterl cuneiform nd cuoid, respectively. The most significnt indictors of instility re the positions of the second nd fourth mettrsls (Fig.10.2-). Injuries to the midfoot ffecting the trsomettrsl or Lisfrnc joints cn e difficult to dignose nd tret. These injuries encompss wide spectrum, from simple sprins to grossly unstle disloctions. They cuse severe long-term moridity if not ppropritely treted. Up to 20% of such injuries go unrecognized s mny pper to reduce spontneously, lthough on closer exmintion they remin displced. As result, mny ptients re sent home with dignosis of foot sprin. Advnced imging techniques, such s CT or MRI, demonstrte the 3-D ntomy of the trsomettrsl joint complex nd my e helpful in ssessing ssocited injuries, such s frctures t the mettrsl ses. Untreted Lisfrnc injuries hve poor outcome. Thus, ny trumtic mechnism with significnt midfoot pin or swelling should rouse suspicion of possile Lisfrnc injury. As yet no system exists to id in determining tretment or predicting outcome. Lisfrnc injuries re clssified ccording to susequent instility ptterns [ 8]: homolterl (medil or lterl); divergent (prtil or complete) (Fig.10.2-7). 3.3 Cliniclly, these injuries re pinful during plption over the trsomettrsl joint. There is often dorsl midfoot swelling long with medil plntr ruising. If the ptient is le to stnd, he/she my hve pin with single lim heel rises. Comprtment syndrome is possile in cses with significnt swelling. If possile, stndrd weight ering x-rys of the foot should e otined (AP, lterl, nd 30 internl olique views). Stress views help to revel displcement in cses of spontneous reduction; however, they re pinful nd should e done under n nesthetic lock or sedtion. One should look for devitions of norml lignment etween ech mettrsl se nd its opposing trsl one. Any displcement > 2 mm on stndrd or Preopertive plnning Initil mngement of Lisfrnc injuries centers on the soft tissues. Elevtion of the foot to hert level (not higher) helps to decrese swelling, while voiding potentil lck of circultion to the injured extremity (pressure hed effect). Close monitoring for comprtment syndrome is dvised. The use of the foot pump hs een shown to speed up resolution of swelling ut is controversil especilly in light of possile comprtment syndrome. Stle injuries my occur s the result of seemingly innocuous ccidents, such s stumling off of cur. Stle injuries my e treted nonopertively with immoiliztion in short leg 924 PFxM2_Section II.ind 924 9/19/11 3:11:24 PM
.10.2 Midfoot nd forefoot c d c Fig.10.2- d Fig.10.2-7 c An AP x-ry tht demonstrtes loss of norml reltionship injuries. Descriptive clssifiction of trsomettrsl etween the second mettrsl nd the intermedite cunei- Divergent (complete). form. Medil divergent (incomplete). c Olique x-rys tht show norml left () nd n injured right c Complete lterl divergent. foot (c) with norml reltionship of the third nd fourth mettrsl to the lterl cuneiform nd cuoid. d A lterl x-ry tht shows dorsl displcement of the first mettrsl in reltion to the cuneiform. 925 PFxM2_Section II.ind 925 9/19/11 3:11:27 PM
.10 Specific frctures Foot cst (with the forefoot dducted), followed y postopertive oot, with progressive weight ering s tolerted fter 8 weeks. Usully, full weight ering should e delyed for 3 months. At 3 months, if free of pin, the ptient my fully er weight nd egin rehilittion. A cushioned insert with medil posting is used to support the rch. Any Lisfrnc joint with displcement of > 2 mm compred to norml joint position on plin, stress, or weight-ering x-rys is considered unstle, nd opertive tretment is indicted. It is impertive to tret these injuries erly nd ggressively. Emergency tretment includes closed reduction nd splinting to protect the soft tissues. Reduction is often difficult due to cpsule interposition, vulsion frgments, joint surfce impction, or interposition of the tendon of the tiilis nterior in the first interspce. The timing of surgery nd the plcement of the incision re determined y the soft tissues. Sutle injuries with miniml swelling should e treted lmost immeditely. Acute disloctions should e reduced within 4 hours s circultion to the forefoot cn e compromised. Significnt soft-tissue injury necessrily delys opertive tretment, the exception eing comprtment syndrome, where the definitive tretment my occur t the sme time s the decompression. Good imging of oth the injured foot nd the contrlterl foot is helpful for proper plnning. 3.4 Opertive tretment Although there is regionl vrition in pproches, the doule-incision dorsl pproch is preferred ecuse it llows excellent inspection nd reduction. The incisions re centered over the first nd fourth mettrsl nd the trsomettrsl joints, nd dissection continues stright down without under- mining. This protects the neurovsculr undle nd soft tissues etween the two incisions. Once t the periosteum, medil nd lterl dissection is llowed. The first trsomettrsl joint nd the medil hlf of the second trsomettrsl joint re pproched through the medil incision. The lterl hlf of the second trsomettrsl joint nd the third trsomettrsl joint re pproched through the lterl incision. The fourth nd fifth trsomettrsl joints usully reduce with the medil mettrsls. After incision nd exposure, the joint surfces must e freed of deris, cpsulr interposition, nd ny impediments to reduction. Screws should e solid with low profile hed nd lrge shft. The 3.5 mm cortex screw is preferred round the midfoot. Cnnulted screws should not e used in this re s they do not hve sufficient strength to resist the forces here. Screw heds must e countersunk to prevent dorsl corticl rekout s the hed engges (Fig.10.2-8). The se of the second mettrsl is reduced into its keystone position nd lg screw is plced from the medil cuneiform through the se of the second mettrsl. The first trsomettrsl joint is then reduced from the dorsl first mettrsl se to the medil cuneiform using lg screw. If second screw is needed, it is plced from the dorsl medil cuneiform to the plntr spect of the first mettrsl. The third trsomettrsl joint is then reduced nd stilized with lg screw from the third mettrsl into the intermedite or lterl cuneiform (Fig.10.2-9). Ech of these joints should e provisionlly fixed with 1. mm K-wires efore the screws re plced. The position should e checked with the imge intensifier. The lterl column is stilized using indirect reduction nd percutneous fixtion with K-wires. If primry fusion of the first three trsomettrsl joints is desired (s in the cse of purely ligmentous injuries), the rticulr crtilge should e ppropritely removed nd one grft should e plced. In lte cses, pes equinus contrcture 92 PFxM2_Section II.ind 92 9/19/11 3:11:27 PM
.10.2 Midfoot nd forefoot is often present. An Achilles tendon lengthening should e performed t the time of initil surgery s it is elieved tht coexisting pes equinus contrcture cuses undue stress cross the midfoot. This cn contriute to lte filure nd joint rthritis. Some dvocte reduction nd fixtion of smll frgments t the mettrsl ses efore definitive ORIF is performed. This cn e helpful in very unstle injury ptterns. Fig.10.2-8 Lterl () nd AP () view of the first mettrsl. A dorsl notch in the mettrsl shft will prevent the dorsl cortex the screw hed. The drill hole should e plced in the top of the notch. from splitting on screw insertion nd will reduce the prominence of Fig.10.2-9 d Reduction nd fixtion of Lisfrnc injury. Reduction nd initil screw plcement. c d c Medil column fixtion. d Lterl column fixtion with K-wires. 927 PFxM2_Section II.ind 927 9/19/11 3:11:29 PM
.10 3.5 Specific frctures Foot Postopertive tretment A short leg splint is used to initilly immoilize the injured foot. 2 weeks fter surgery the splint is exchnged for cst or postopertive oot. Weight ering progresses s tolerted fter pproximtely 8 weeks. Full weight ering is not llowed until 3 months postopertively. Ptients my multe without cst/rce when they cn do so pinlessly. A medil, cushioned rch support should e used to protect the foot. Lterl column K-wires should e removed t 8 weeks. First, second, nd third trsomettrsl joint screws my sty in permnently unless symptomtic. However, they should remin in plce for minimum of months. Hrdwre removl is prcticed differently y mny surgeons nd is not required routinely. 3. 4 4.1 Mettrsl frctures Principles The im of reconstruction fter frctures is the functionl lignment of the mettrsl heds with functionl moility of the mettrsophlngel joints. In this respect, ctive flexion of the mettrsophlngel joints is essentil for pinless git. Correct lignment of the mettrsl heds must include lignment in the horizontl plne s well s in the sgittl plne. The ltter lso depends upon moility of the corresponding trsomettrsl joint. Consequently, individul shortening or ngultion of the mettrsl must e voided. 4.2 Tretment 4.2.1 Single-ry frctures Results A direct correltion hs een found etween ntomicl reduction nd good x-ry or clinicl outcomes [4, 5]. Poorer outcomes hve een noted for purely ligmentous injuries [9]. For these resons, mny surgeons choose to primrily fuse the injured joints. If pes equinus contrcture is present, n Achilles tendon lengthening should e performed t the time of definitive surgery for this injury. The mjority of frctures re loclized on the first nd fifth ry. If the locl soft tissues do llow open reduction, fixtion with screws, or with plte nd screws permits immedite, functionl, postopertive tretment with prtil weight ering. The first ry is est fixed with plte 2.7 or 2.4. The fifth ry cn e treted nonopertively, if nondisplced, or opertively, if displced. If displced, the fifth ry is est fixed using plte 2.0 nd/or 2.0 mm screws (Fig.10.2-10). 4.2.2 Multiple-ry frctures In cses of multiple frctures situted proximl to the mettrsl heds, the intermettrsl ligment (first ry excepted) hs n importnt role in stiliztion. If the frctures re trnsverse, the mettrsls do not tend to shorten due to sher: Fixtion y mens of multiple intrmedullry K-wires my e very efficient. The wires must e inserted through the plntr side of the phlnx, thus trnsfixing nd holding the corresponding mettrsophlngel joint in n ntomicl position (Fig.10.2-11;.10.2-12). 928 PFxM2_Section II.ind 928 9/19/11 3:11:29 PM
.10.2 Fig.10.2-10 Midfoot nd forefoot Fifth mettrsl frcture treted with 2.0 mm lg screws. Mettrsl lignment with K-wires to prevent dor- Fig.10.2-12 sl displcement or ngultion of the distl frgment. The wire must with K-wires. Fig.10.2-11 Second to fifth mettrsl frctures fixed trnsfix the mettrsophlngel joint to llow correct lignment of the mettrsl. 929 PFxM2_Section II.ind 929 9/19/11 3:11:30 PM
.10 4.2.3 Specific frctures Foot Unstle nd intrrticulr frctures In olique distl frctures, xil shortening is likely. In these cses s well s in ll other cses with n ovious risk of xil shortening or ngultion, open plte nd screw fixtion must e considered (Fig.10.2-13). The pproches cn e linked for the second nd third rys (intermettrsl longitudinl pproch). The fourth nd fifth mettrsls cn e fixed through the respective intermettrsl dorsl pproch s well. We do not dvocte trnsverse pproches. The first nd isolted fifth mettrsls re est fixed through longitudinl medil incision (on the upper edge of the ductor hllucis tendon nd longitudinl lterl incision (on the upper edge of the ductor digiti tendon). 4.2.4 Frctures of the proximl fifth mettrsl Intrrticulr frctures of the proximl fifth mettrsl re est treted nonopertively, even if the frcture is displced. Tretment is symptomtic, reducing pin while wlking with dequte mens such s cm wlker [10]. Extrrticulr, metphysel frctures, so-clled Jones frctures, undergo high locl strin due to the pull of the fiulris tertius muscle. Surgicl tretment y primry open reduction nd fixtion with plte nd 2.4 or 2.7 mm screws cn e considered. 5 Fig.10.2-13 Fixtion of unstle second nd third mettrsl frctures. Frctures of sesmoid ones These re rre frctures nd usully hel spontneously. In cse of persisting pin tht cn e ttriuted to such n injury, ORIF with one or two 1.5 mm screws my e indicted (Fig.10.2-14). Fig.10.2-14 Pinful lterl sesmoid frcture fixed with two 1.5 mm lg screws. 930 PFxM2_Section II.ind 930 9/19/11 3:11:31 PM
.10.2 Midfoot nd forefoot Biliogrphy [1] wipp H, Bumgrt F, Cronier P, et l (2004) Integrl clssifiction Z of injuries (ICI) to the ones, joints, nd ligments ppliction to injuries of the foot. Injury; 35(Suppl 2):3 9. [2] Hermel MB, Gershon-Cohen J (1953) The nutcrcker of the cuoid y indirect violence. Rdiology; 0():850 854. [3] Zwipp H (1994) [Surgery of the foot.] 1st ed. Wien New York: SpringerVerlg. [4] Richter M, Wippermn B, Krettek C, et l (2001) Frctures nd frcture disloctions of the midfoot: occurrence, cuses nd long-term results. Foot Ankle Int; 22(5):392 398. [5] Kuo RS, Tejwni NC, DiGiovnni CW, et l (2000) Outcome fter open reduction nd internl fixtion of Lisfrnc joint injuries. J Bone Joint Surg Am; 82(11):109 118. [] Hrdcstle PH, Reschuer R, Kutsch-Lisserg E, et l (1982) Injuries to the trsomettrsl joint. Incidence, clssifiction nd tretment. J Bone Joint Surg Br; 4(3):349 35. [7] Arntz CT, Hnsen ST Jr (1987) Disloctions nd frcture disloctions of the trsomettrsl joints. Orthop Clin North Am; 18(1):105 114. [8] Myerson MS, Fisher RT, Burgess AR, et l (198) Frcture disloctions of the trsomettrsl joints: end results correlted with pthology nd tretment. Foot Ankle; (5):225 242. [9] Mulier T, Reynders P, Dereymekr G, et l (2002) Severe Lisfrnc injuries: primry rthrodesis or ORIF? Foot Ankle Int; 23(10):902 905. [10] Dmeron TB Jr (1995) Frctures of the proximl fifth mettrsl: selecting the est tretment option. J Am Acd Orthop Surg; 3(2):110 114. 931 PFxM2_Section II.ind 931 9/19/11 3:11:31 PM