Elbow your way into reporting paediatric elbow fractures A simple approach

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1 Pge 1 of 10 Elow your wy into reporting peditric elow frctures A simple pproch Authors: Trcy Kilorn 1 Hlvni Moodley 1 Stewrt Mers 1 Affilitions: 1 Red Cross Wr Memoril Children s Hospitl, Cpe Town, South Afric Correspondence to: Trcy Kilorn Emil: trcykilorn@gmil.com Postl ddress: Red Cross Wr Memoril Children s Hospitl, Klipfontein Rod, Cpe Town 7700, South Afric Dtes: Received: 02 June 2015 Accepted: 11 Aug Pulished: 18 Dec How to cite this rticle: Kilorn T, Moodley, H, Mers, S. Elow your wy into reporting peditric elow frctures A simple pproch. S Afr J Rd. 2015;19(2): Art. #881, 10 pges /sjr.v19i2.881 Copyright: The Authors. Licensee: AOSIS OpenJournls. This work is licensed under the Cretive Commons Attriution License. The evlution of X-rys of the peditric elow in the setting of trum is chllenging. The difficulty rises from the complex developmentl ntomy of the elow, with its multiple ossifiction centres nd the differences in the pttern of injuries etween dults nd children. It is essentil to evlute the rdiogrphs systemticlly. This review will provide n overview of the developmentl ntomy, the rnge of soft tissue nd skeletl findings, nd demonstrte tips nd pitflls in rdiogrphic interprettion in peditric elow trum. Introduction Peditric elow trum is common. Rdiogrphic dignosis of the vrious frcture types is criticl due to the overlpping clinicl presenttions nd to void misdignosis tht cn result in growth disturnces. A systemtic pproch to reporting, supported y n understnding of the ge-dependent vrition in developmentl ntomy of the elow, is indispensle to the rdiologist in tckling these chllenging injuries. We now discuss prcticl nd simple guide to post-trumtic peditric elow rdiogrphic reporting. A systemtic pproch to reporting Reporting checklist 1 1. Techniclly dequte film (AP nd lterl). 2. Soft tissue swelling nd joint effusion (ft pds). 3. Alignment nterior humerl nd rdiocpitellr lines. 4. Ossifiction centres (CRITOL). 5. Visile frcture of distl humerus. 6. Visile frcture of rdius or uln. 7. No visile frcture ut positive ft pd follow up in 7 10 dys. Step 1 Evlute rdiogrphic technique Initil rdiogrphic interprettion consists of the nteroposterior (AP) nd lterl projections. The AP should e performed with the elow in full extension nd the forerm supinted (Figure 1). For the true lterl projection, the elow should e flexed 90 degrees with the forerm supinted (Figure 2). The cssette should e centred on the elow joint with its long xis prllel to the forerm. In n optiml lterl projection, the posterior suprcondylr ridges of the humerus re superimposed nd the olecrnon process is viewed in profile (Figure 3). Rdiogrphic lndmrks re unrelile nd significnt pthology cn e oscured in suoptiml lterl projection. The internl olique view is useful in the demonstrtion of lterl condyle frctures nd in ssessing the degree of displcement. 2 The routine use of comprtive views is not recommended s it comes t considerle cost of rdition exposure to the child. 3 In ddition, severl studies hve shown tht the routine use of comprtive views ws predominnt choice of inexperienced clinicins, did not lter ptient mngement in the mjority of cses nd therefore could not e justified. 4,5,6,7 Red online: Scn this QR code with your smrt phone or moile device to red online. Step 2 Look for soft tissue swelling nd joint effusion Loclised soft tissue swelling either over the medil or the lterl spects of the elow should rise suspicion of medil epicondylr or lterl condylr frcture. The elow ft pds re situted externl to the synovium. On true lterl rdiogrph with 90 degrees of flexion the norml nterior ft pd is within the coronoid foss nd is seen s rdiolucent line prllel to the nterior humerl cortex; the posterior ft pd is pressed deep into the olecrnon foss y the triceps tendon nd the nconeus muscle nd is invisile. 8 Distention

2 Pge 2 of 10 they do stress tht these investigtions did not significntly lter mngement.10,11. The stndrd protocol for suspected occult frctures in most institutions remins posterior elow splinting with follow-up rdiogrphs t 7 10 dys. Step 3 Evlute lignment The nterior humerl nd rdio-cpitellr lines should e used to guge elow lignment. FIGURE 1: Positioning for the nteroposterior (AP) projection. The elow should e in contct with nd in the middle of the cssette in full extension with the forerm supinted. FIGURE 2: Positioning for the lterl projection. The elow should e flexed t 90 degrees with the forerm supinted nd thum superior. The nterior humerl line is drwn long the nterior cortex of the humerus nd should isect the middle third of the cpitellum. Since the line evlutes the reltive positions of two prts of the sme one, mllignment indictes frcture in most cses, posterior displcement of the cpitellum in suprcondylr frcture. This sign relies on dequte ossifiction of the cpitellum nd therefore is relile in children over the ge of 4 yers only.12 In younger children when the cpitellr ossifiction centre is still smll, the nterior humerl line my not pss through the ossified portion (Figure 4). The rdiocpitellr line evlutes the reltionship of the proximl rdius to the cpitellum on ll views. If the integrity of this line is compromised, then disloction should e suspected (Figure 5). of structurlly intct joint cuses displcement of the ft pds the posterior ft pd moves posterior nd superior nd ecomes visile; the nterior ft pd ecomes more sil-like (Figure 3). A flse negtive ft pd sign my occur in poor positioning, in cpsulr rupture or in the setting of significnt extrcpsulr normlity.8 Approximtely 70% 90% of children with n elow effusion will hve visile frcture; however, there is wide dete in the literture out the presence of rdiogrphiclly occult frctures in the setting of joint effusion t presenttion rdiogrphic follow-up y Donnelly et l reported 54% of ptients showing heling frctures.9 More recent studies looking t MRI nd MDCT show occult frctures in the mjority of ptients, lthough FIGURE 4: () Norml nterior humerl line in 4 yer old psses through the middle third of the cpitellum (lck line). () Anterior humerl line in 6 month old child with will not pss through the middle third of the prtilly ossified cpitellum (lck line). FIGURE 3: () Good qulity lterl projection with the posterior suprcondylr ridges superimposed nd olecrnon in profile. Note the norml nterior ft pd lying prllel to the nterior humerl shft (rrow). () Lterl projection in ptient with rdil neck frcture showing posterior ft pd (long rrow) nd displced nterior ft pd (short rrow). FIGURE 5: () Norml rdiocpitellr line (lck line). () Displced rdiocpitellr line tht does not intersect the cpitellum in rdil disloction (lck line).

3 Pge 3 of 10 Step 4 Identify ossifiction centres Although ossifiction of the elow is complex, this knowledge is essentil to ll prctitioners involved in the evlution of peditric trum. The ossifiction ppers erlier in girls thn in oys nd there is wide vrition etween individuls of the sme sex. In oys, with the exception of the cpitellum, n verge dely of two yers is seen when compred to girls nd there re lso differences etween popultion groups.13,14,15 The sequence of ppernce of the six centres of secondry ossifiction is mostly predictle (Tle 1) nd is est rememered y using the cronym CRITOL (Figure 6). It should e noted tht there re no specific reference dt out the timing nd sequence of ossifiction in South Africn children, nd previous study showed differences in the sequence of ossifiction in Chinese children when compred to the reported stndrds.14 Step 5 Look for distl humerl frctures ) Suprcondylr frcture (50% 70%) (Digrm 1) TABLE 1: Ossifiction centres.13,14,15 Ossifiction centre Averge ge girls (rnge) Averge ge oys (rnge) Appernce Cpitellum 3 12 months 3 12 months Single smooth centre Rdil 5 y ( y) 5 y ( y) Ovl then flttened Internl (medil) epicondyle 5 y ( y) 7 y ( y) Single 9 y (6 11 y) 10.5 y ( y) Two or more, frgmented nd cn project into joint Olecrnon 9 y ( y) 11 y ( y) Biprtite, irregulr nd sclerotic Lterl epicondyle 10 y ( y) 12 y (8 14 y) Single or multiple Trochle C pitellum None I nt. epicondyle R dil hed O lecrnon T rochle L t. epicondyle DIAGRAM 1 Birth 3m 5y 5 7y y 9 11y 10 12y FIGURE 6: Timeline of the ppernce of ossifiction centres. T!PS Lterl view most helpful look for posterior ft pd. Anterior humerl line norml in 94% cses (Figure 7). Bumnn s ngle predicts vrus deformity. c d FIGURE 7: Type 1 suprcondylr frcture on () AP nd () lterl (rrow) with positive posterior ft pd nd intct posterior cortex. Note with the incompletely ossified cpitellum tht one cnnot use the nterior humerl line to ssess lignment. (c) Type 2 suprcondylr frcture showing posteriorly displced frgment s evidenced y norml nterior humerl line (lck line), lthough frcture is visile, posterior cortex is intct(white rrow) nd positive posterior ft pd. (d) Type 3 suprcondylr frcture with displced frgment (rrow), discontinuous nterior humerl line (lck line) nd posterior ft pd.

4 Pge 4 of 10 Mlunion cuses vrus normlity, the severity of which is mesured on the true AP projection y the Bumnn ngle, which uses rdiogrphiclly identifile lndmrks to compre the heled with the norml elow (Figure 8). Although primrily cosmetic deformity, it my cuse pin nd lte development of posterolterl elow instility, which cn e corrected with vlgus osteotomy. Not to e missed look like Non-ccidentl injury (NAI) FIGURE 9: () AP nd () Lterl views in one-month-old with swollen elow who died soon fter dmission. Note the mrked soft tissue swelling, the presence of posterior ft pd nd the ucket hndle metphysel frcture. Multiple dditionl frctures were identified t post mortem. FIGURE 8: Bumnn s ngle (shown) is formed y the intersection of line drwn perpendiculr to the humerl shft nd line long the physis of the lterl condyle. A norml Bumnn s ngle within the peditric popultion rnges from degrees. It is importnt to compre ngles etween the norml nd norml side, difference of more thn 5 degrees predicts possile vrus deformity. Non-moile infnt. History will e suspicious. Bucket hndle or corner frcture of distl humerus. Requires full skeletl survey.

5 Pge 5 of 10 ) Lterl condyle 10% 15% (Digrm 2) c) Medil epicondyle 10% (Digrm 3) DIAGRAM 2 Second most common frcture, so look crefully. Lterl soft tissue swelling is the clue on AP view. Corticl rech is posterior on lterl view. Need to document mount of displcement. Internl olique view helpful (Figure 10). DIAGRAM 3 Displcement est seen on AP view. Look for medil soft tissue swelling. Alwys confirm norml position in child >6 yers. If no epicondyle seen, look for entrpment in the joint (Figure 11). c FIGURE 10: () Undisplced right lterl condyle frcture (long rrow). Note lterl soft tissue swelling (short rrow). () Displced right lterl condyle frcture (rrow). (c) Internl olique showing left lterl condyle frcture tht ws suspected ut not visile on the AP projection.

6 Pge 6 of 10 c d e FIGURE 11: () Right medil epicondyle frcture (long rrow) with miniml displcement treted conservtively. Note the striking medil soft tissue swelling (short rrow). () AP nd (c) lterl projections of six-yer-old. The rdiocpitellr line is roken (lck line), in keeping with disloction. Medil soft tissue swelling nd sence of the norml medil epicondyle (white rrow) in child of this ge should prompt creful evlution for n entrpped epicondyle within the joint (white nd lck rrow). (d) Post reduction imge of the sme child s ( nd ), showing rdiocpitellr lignment (lck line) nd relocted medil epicondyle (lck rrow). (e) AP of right elow in nine-yer-old the ossifiction centre of the trochle is normlly positioned (T); the medil epicondyle is not seen (short rrow) s it lies trpped within the joint (white nd lck rrow).

7 Pge 7 of 10 d) Medil condyle (<1%) (Digrm 4) e) Lterl epicondyle (<1%) (Digrm 5) DIAGRAM 4 Look for medil soft tissue swelling. Uncommon. Often difficult to differentite from medil epicondyle frcture. My e difficult to see extent; externl olique projection helpful (Figure 12). DIAGRAM 5 Very rre! Mke sure you re not looking t lterl condyle frcture insted. Only ossifies fter 11 yers. Lterl soft tissue swelling my e only finding. Internl olique projection my e helpful ( Figure 13). 16 FIGURE 12: Left medil condyle frcture in 4 yer old. Note the medil soft tissue swelling (short rrow) nd the sutle frcture line involving the medil condyle (long rrow). FIGURE 13: A 12-yer-old with direct low to elow. Note the lterl soft tissue swelling nd liner frcture through the lterl epicondyle (rrow).

8 Pge 8 of 10 f) Intercondylr <1% (Digrm 6) DIAGRAM 7 DIAGRAM 6 Often misdignosed s suprcondylr frcture. Look for sgittl component tht splits medil nd lterl condyles nd extends to rticulr surfce ( Figure 14). Rdius nd uln not ligned with humerus on lterl. NB: Rdiocpitellr line is mintined; cf. disloction (Figure 15). FIGURE 14: Intercondylr frcture tht extends sgittlly to the rticulr surfce (lck nd white rrow) splitting the medil nd lterl condyles (white rrows). g) Trnscondylr (trnsphysel) <1% (Digrm 7) Mimics posterior disloction. FIGURE 15: () Lterl projection in neonte with swollen elow shows mrked soft tissue swelling. Uln nd rdius pper posteromedilly displced (rrow). () AP projection with line drwn long rdil shft tht intersects with expected position of the cpitellum excluding disloction nd implying trnscondylr frcture.

9 Pge 9 of 10 TABLE 2: Summry of peditric elow frcture/disloctions. 1,15 Frcture type Prevlence Ages (yrs) Mechnism of injury Clssifiction Mngement Tips nd pitflls Suprcondylr 50% 70% 3 10 Fll on n outstretched hnd hyperextension (95%) Lterl condyle 10% 15% 6 10 Vrus force pplied to extended elow while forerm supinted. Medil condyle <1% 8 14 Fll onto flexed elow or outstretched rm Lterl epicondyle Rre 9 15 Owing to trction on extensor mechnism. In older child, due to direct low Medil epicondyle 10% 7 15 Vlgus stress vulsing epicondyle y forerm flexor prontor tendons. Cn e frctured y direct force Intercondylr/ <1% 9 13 Flexion or extension T-condylr/Y-condylr injury Trnsphysel/ trnscondylr <1% <2 Birth trum, fll on outstretched hnd, NAI Olecrnon 4% 7% Fll on outstretched hnd or direct trum Proximlrdius (hed nd neck) 4% 5% Fll on outstretched hnd Elow disloction 3% 5% Fll on outstretched hnd, forerm supinted, elow fully extended/prtilly flexed According to Grtlnd: Type 1 Non-displced Type 2 Distl frgment posteriorly displced, posterior cortex retined, cts s hinge Type 3 Circumferentil corticl rech, displced frgment. Type 1 Incomplete; frcture does not trverse epiphysis. Non = displced Type 2 Complete ut not displced Type 3 Complete with displced/ rotted frgment. Cn e Slter-Hrris Type 2, 3 or 4 Bsed on loction nd displcement usully Slter-Hrris Type 4 Slter-Hrris Type 3 or 4 Type 1 Splint/cst Type 2/3 Closed reduction nd percutneous pinning Non-displced Posterior splinting Displced > 2 mm Open reduction nd percutneous pinning Undisplced conservtive. Displced or unstle pinning Undisplced conservtive. Displced fixtion nd immoilistion <5 mm displcement conservtive mngement. >5 mm institutionl specific. Incrcerted frgments open reduction nd screw fixtion when closed reduction fils to extrude frgment from joint Opertive Best identified on lterl. 25% re sutle, common cuse of occult frcture. Associted with ipsilterl distl rdil frcture. Type 3 mlunion nd neurovsculr complictions Frcture line usully rely visile. Since frcture is through crtilge, it is difficult to know extent (MRI cn ssist). Internl olique view helpful. NB to document displcement. Suspected non-displced frctures do seril rdiogrphs to see cllus formtion Often confused with medil epicondyle frcture. Not relted to disloction. Usully unstle Usully seen in setting of other injuries. Comment on displcement nd rottion. Does not contriute to growth discrepncy Older children thn SC/LC. Entrpment est seen on lterl. Usully no joint effusion. 50% ssocited with posterior elow disloctions. If equivocl or unossified, needs evlution with MRI Uncommon prior to skeletl mturity. Often misdignosed s suprcondylr, lterl/ medil condylr frctures Slter-Hrris Type 1 Conservtive mngement Cn e misdignosed s posteromedil disloction. NB: Rdiocpitellr lignment is norml. Hs high index of suspicion for NAI Usully Slter-Hrris Type 2. Slter-Hrris Type 1 cn occur, ut uncommon O Brien Clssifiction 1 < 30 degrees ngultion. 2 ngulted degrees. 3 > 60 degrees Non- or minimlly displced (mjority) cst immoilistion Displced screw fixtion/tension nd constructs Uncomplicted posterolterl disloction closed reduction. Entrpped medil epicondylr frgment open surgicl reduction my e necessry Ossifies t 10 y nd fused y 18 y. Biprtite/eccentric, irregulrly or diffusely sclerotic olecrnon ossifiction centre do comprison lterl view if unsure. NB: 14 77% ssocited rdil neck frcture, lterl or medil condylr frcture or rdil hed disloction Olique views my disclose sutle frctures Posterior disloction of rdius nd uln with typicl lterl displcement is most common Associted frcture in 64% of posterior disloctions (medil epicondyle/ condyles/rdil neck)

10 Pge 10 of 10 Step 6 Look for rdil nd/or ulnr frctures. ) Olecrnon frcture 4% 7% Norml ossifiction centre my e frgmented. Look for soft tissue swelling. Look for ssocited frctures of medil nd lterl condyles nd rdil neck. Look for elow disloction (Figure 16). Conclusion A systemtic pproch to peditric elow reporting in the post-trumtic setting is n sset for everydy rdiologicl prctice. Knowledge of the developmentl ntomy of the elow underscored y n understnding of common mimics nd pitflls is fundmentl. Acknowledgements Competing interests The uthors declre tht they hve no finncil or personl reltionships which my hve inppropritely influenced them in writing this rticle. Author s contriution FIGURE 16: () Soft tissue swelling overlying the olecrnon, which hs sutle undisplced frcture (rrow). () Olecrnon frcture (rrow) in the setting of disloction. Note the interrupted rdiocpitellr line (lck line). ) Proximl rdil frcture 4% 5% Neck more common thn hed. Posterior ft pd is clue. Olique views re helpful. In rdil disloction, look for ssocited uln frcture (Figure 17). FIGURE 17: () Lterl nd () olique imges of four-yer-old with rdil neck frcture (rrows). (c) A five-yer-old with rdil disloction (note interrupted rdiocpitellr line) nd proximl ulnr frcture. c T.K. (Red Cross Wr Memoril Children s Hospitl) Written text nd legends. Grphics. H.M. (Red Cross Wr Memoril Children s Hospitl) - Digrms, figures, dt collection. S.M. (Red Cross Wr Memoril Children s Hospitl) Fct checking, editing, figures nd legends. References 1. Iyer RS, Thp MM, Khnn PC, Chew FS. Peditric one imging: Imging elow trum in children A review of cute nd chronic injuries. AJR. 2012;198: PMID: , 2. Song KS, Kng CH, Min BW, Be KC, Cho CH. Internl olique rdiogrphs for dignosis of nondisplced or minimlly displced lterl condylr frctures of the humerus in children. J Bone Joint Surg Am. 2007;89(1): PMID: , 3. Johnson KL, Bche E. In Peditric skeletl trum Techniques nd pplictions. Berlin Heidelerg New York: Springer; Chcon D, Kissoon N, Brown T, Glpin R. Use of comprison rdiogrphs in the dignosis of trumtic injuries of the elow. Ann Emerg Med. 1992;21 (8): PMID: , 5. Kissoon N, Glpin R, Gyle M, Chcon D, Brown T. Evlution of the role of comprison rdiogrphs in the dignosis of trumtic elow injuries. J Peditr Orthop. 1995;15(4): PMID: Rickett AB, Finly DB. An udit of comprtive views in elow trum in children. Br J Rdiol. 1993;66(782): PMID: , org/ / Dowling S, Frion K, Clifford T. Comprison views to dignose elow injuries in children: A survey of Cndin non-peditric emergency physicins. Cn J Emerg Med. 2005;7(4): PMID: Goswmi GK. The ft pd sign. Rdiology. 2002;222: org/ /rdiol Donnelly LF, Klostermeier TT, Klostermn LA. Trumtic elow effusions in peditric ptients: Are occult frctures the rule? AJR. 1998;171: PMID: , Mjor NM, Crwford ST. Elow effusions in trum in dults nd children: Is there n occult frcture? AJR. 2002;178: PMID: Chpmn V, Grottku B, Alright M, Elini A, Hlpern E, Jrmillo D. MDCT of the elow in peditric ptients with posttrumtic elow effusion. AJR. 2006;187: PMID: , Hermn MJ, Bordmn MJ, Hoover JR, Chfetz RS. Reltionship of the nterior humerl line to the cpitellr ossific nucleus: Vriility with ge. J Bone Joint Surg Am. 2009;91(9): PMID: , JBJS.H Ptel B, Reed M, Ptel S. Gender-specific pttern differences of the ossifiction centres in the peditric elow. Peditr Rdiol. 2009;39: PMID: , Cheng JC, Wing-Mn K, Shen WY, et l. A new look t the sequentil development of elow-ossifiction centres in children. J Peditr Orthop. 1998;18(2): PMID: Bety JH, Ksser JR. Rockwood nd Wilkins frctures in children. 6th ed. Lippincott Willims & Wilkins; 2006.