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Orthopedic                                 Anatomy                Handout download:                http://www.oucom.ohiou....
Brachial PlexusTraumatic injury:• Terminal branches• Ventral rami  brachial  plexus  injuries                      From Ne...
Upper Brachial Plexus Injuries           Upper brachial• Increase in angle between neck &       plexus injuriesshoulder• T...
Upper Brachial Plexus Injury: Erb’s Palsy                             • Appearance: drooping, wasted shoulder; pronated   ...
Lower Brachial Plexus Injury: Klumpke’s Palsy                             • Much rarer than UBPIs and Erb’s Palsy         ...
Case Presentation                             A 5-year-old boy is brought to the pediatrician with                        ...
Congenital Muscular Torticollis head  tiltsipsilat.                           chin                          raised        ...
Sternocleidomastoid                             • Attachments: proximally,                                 mastoid proc. &...
Asymmetries Secondary to Congenital Muscular Torticollis    • Ipsilateral shortening and flattening of face; ipsilateral d...
“Pulled (Nursemaid’s) Elbow”                               • Very common in children under 4 (peak: ages 1–3)             ...
Subluxation of the         Radial Head       (“pulled elbow”)• Annular lig. joins radial head to ulna• Traction on pronate...
Why Subluxation in Pronation?               • Annular ligament restrains radial head, while               allowing axial r...
Interposition of the Annular Ligament                          • Extent of interposition of the annular ligament          ...
“Breaking News”          Self-Actuating Extendible Endoprothesis                                 • Reported in Nature (Jul...
ReferencesBayne, L. G., and B. L. Costas. 1990. Malformations of the upper limb, pp. 1091–    1128 in R. T. Morrissy (ed.)...
brief communicationsA self-extending paediatric leg implantThis device spares the need for surgical intervention by simula...
brief communications3. Scales, J. T., Sneath, R. S. & Wright, K. W. J. in Limb Salvage         591–599 (Springer, Berlin, ...
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Peds ortho-anatomy

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  1. 1. Orthopedic Anatomy Handout download: http://www.oucom.ohiou.edu/dbms-witmer/peds-rpac.htmLawrence M. Witmer, PhDDepartment of Biomedical SciencesCollege of Osteopathic MedicineOhio UniversityAthens, Ohio 45701witmer@exchange.oucom.ohiou.edu 20 September 2000
  2. 2. Brachial PlexusTraumatic injury:• Terminal branches• Ventral rami brachial plexus injuries From Netter 1997
  3. 3. Upper Brachial Plexus Injuries Upper brachial• Increase in angle between neck & plexus injuriesshoulder• Traction (stretching or avulsion) ofupper ventral rami (e.g., C5,C6)• Produces Erb’s PalsyLower Brachial Plexus Injuries• Excessive upward pull of limb• Traction (stretching or avulsion) of Lower brachiallower ventral rami (e.g., C8, T1) plexus injuries• Produces Klumpke’s Palsy“Obstetrical” or “Birth palsy”• Becoming increasingly rare• Categorized on basis of damage • Type I: Upper (C5,6), Erb’s • Type II: All (C5-T1), both palsies • Type III: Lower (C8, T1), Klumpke’s Palsy From Moore & Dalley (1999)
  4. 4. Upper Brachial Plexus Injury: Erb’s Palsy • Appearance: drooping, wasted shoulder; pronated and extended limb hangs limply (“waiter’s tip palsy”) • Loss of innervation to abductors, flexors,& medial rotators of shoulder and flexors & supinators of elbow • Loss of sensation to lateral aspect of upper extremityFrom Bayne & Costas (1990) From Netter 1997
  5. 5. Lower Brachial Plexus Injury: Klumpke’s Palsy • Much rarer than UBPIs and Erb’s Palsy • Loss of C8 & T1 results in major motor deficits in the muscles working the hand: “claw hand” • Loss of sensation to medial aspect of upper extremity“clawhand”From Moore & Dalley (1999) From Netter 1997
  6. 6. Case Presentation A 5-year-old boy is brought to the pediatrician with the complaint that since early childhood the right side of his neck has been twisted and deformed. Childbirth apparently had been prolonged and difficult and was a breech delivery. Within a few weeks, there was a spindle-shaped swelling on the right side of the neck that was tender on touch and on passive movement of the head. Over the next few months, the swelling and tenderness subsided. By the time the boy was about 1-year-old, the muscle on the right side of the neck appeared cordlike. Gradually the neck became stiff and deformed, as shown at left. The face was also asymmetrical.From Moore & Dalley (1999) Case modified from Cahill (1997)
  7. 7. Congenital Muscular Torticollis head tiltsipsilat. chin raised contralat. fibrous tissue “tumor”From Tachdjian (1990) Sternocleidomastoid (SCM)• Fibromatosis colli that develops in SCM probably prior to birth, although birth trauma (e.g., forceps) has also been implicated• 75% of cases on right side• SCM is transformed into a cordlike, nonfunctional muscle, distorting head and neck posture and altering growth of the face• Etiology is unclear: Arterial or venous obstruction? Intrauterine malposition?
  8. 8. Sternocleidomastoid • Attachments: proximally, mastoid proc. & occ. bone; distally, sternum & clavicle • Innervation: accessory n., C2,3 • Surgical concerns • nerves emerging from post. border (esp. accessory n.) • jugular veins • carotid A. & its branches • Bilateral contraction: flex the neck • pull chin toward sternum • in conjunction with neck extension: protrusion of the chin • Unilateral contraction: ipsilateral neck flexion and contralateral rotation of chin (as in torticollis)From Moore & Dalley (1999)
  9. 9. Asymmetries Secondary to Congenital Muscular Torticollis • Ipsilateral shortening and flattening of face; ipsilateral depression of eye & ear • Contralateral convex scoliosis in lower cervical and upper thoracic regions; compensatory ipsilateral convex scoliosis in middle & lower thoracic regionsPhoto from Tachdjian (1990)Photo from Tachdjian (1990)
  10. 10. “Pulled (Nursemaid’s) Elbow” • Very common in children under 4 (peak: ages 1–3) • More in common in boys; more common on left side • Sudden traction with elbow extended & forearm pronated presentation ouch treatmentFrom Netter 1987
  11. 11. Subluxation of the Radial Head (“pulled elbow”)• Annular lig. joins radial head to ulna• Traction on pronated forearm causes a distal tear in the annular ligament where it merges with the periosteum• Radial head “escapes” anteriorly• Annular ligament slides onto articular surface of radial head, between radial head & capitulum ann. lig.• Above the age of slides proximally entrapmentfive, tear does not of ann. lig.occur because of betweenthicker attachement of distal capitulum &annular ligament to tear radial headperiosteum From Slaby et al. 1994
  12. 12. Why Subluxation in Pronation? • Annular ligament restrains radial head, while allowing axial rotation of the radius • Steep & sharp lip anteriorly between radial head & neck—in supination, annular ligament cannot annular slip proximally over lipligament • Shallower lip laterally and posteriorly • During pronation, rotation of radius brings this shallow lip anteriorly, allowing proximal slip of ann. lig. if there is a transverse tear steep lip shallow lip anteriorly laterally & between posteriolyradial head between and neck radial head and neck From Netter 1997
  13. 13. Interposition of the Annular Ligament • Extent of interposition of the annular ligament within the joint determines course • If ligament does not extend beyond “equator” of radial head (B below), subluxation can be reduced by closed manipulation (passive supination) • If ligament extends beyond equator (A below), open (surgical) reduction may be required equatorFrom Slaby et al. 1994 From Salter & Zalta 1971
  14. 14. “Breaking News” Self-Actuating Extendible Endoprothesis • Reported in Nature (July 2000) by Kotz et al. • Prosthesis designed for children requiring knee replacement (due to malignant bone tumors) • Previous implants required repeated surgery to adjust for growth and to avoid leg-length discrepancy • New device does not require repeated surgery: it extends automatically with flexion of the knee From Kotz et al. 2000
  15. 15. ReferencesBayne, L. G., and B. L. Costas. 1990. Malformations of the upper limb, pp. 1091– 1128 in R. T. Morrissy (ed.), Lovell and Winter’s Pediatric Orthopaedics, Volume 2, 3rd Edition. Lippincott, Philadelphia.Cahill, D. R. 1997. Lachman’s Case Studies in Anatomy, 4th Ed. Oxford University Press, New YorkKotz, R. I., R. Windhager, M. Dominkus, B. Robioneck, and H. Müller-Daniels. 2000. A self-extending paediatric leg implant. Nature 406:143-144.Moore, K. L. and A. F. Dalley. 1999. Clinically Oriented Anatomy. Lippincott, Williams, & Wilkins, Baltimore.Netter, F. H. 1987. The CIBA Collection of Medical Illustrations, Volume 8: Musculoskeletal System. CIBA-Geigy, Summit.———. 1997. Atlas of Human Anatomy, 2nd. Ed. Novartis, East Hanover.Salter, R. B., and C. Zalta. 1971. Anatomic investigations of the mechanism of injury and pathologica anatomy of “pulled elbow” in young children. Clinical Orthopedics 77:141.Slaby, F. J., S. K. McCune, and R. W. Summers. 1994. Gross Anatomy in the Practice of Medicine. Lee & Febiger, Baltimore.Tachdjian, M. O. 1990. Pediatric Orthopedics, Volumes 1–4, 2nd Edition. W. B. Saunders, Philadelphia.Thompson, G. H. & P. V. Scoles. 1999. Bone and joint disorders, pp. 2055-2098 in Nelson’s Textbook of Pediatrics. Saunders, Philadelphia.
  16. 16. brief communicationsA self-extending paediatric leg implantThis device spares the need for surgical intervention by simulating natural limb growth.B iological regeneration of the extremi- ties can occur in some organisms (starfish, for example), but humansneed recourse to a mechanical solution.Growing children present a particular chal-lenge, and those who lose bone tissue fromthe knee after removal of a tumour need animplant that can not only provide stabilityfor the femur and allow motion of the kneejoint, but which also accommodates rapidgrowth. Here we describe a self-extendingleg implant (endoprosthesis) that can close-ly simulate natural growth and which hasworked successfully in paediatric patients.The energy needed for elongation of thisdevice is provided by the patients them-selves as a result of flexure of the knee joint,thereby reducing the number of operationsand the risk of infection associated withmanually extended implants. The outlook for patients with malignantbone tumours has historically been poor,but now increased sophistication in medicalimaging and adjuvant treatment has dra-matically improved survival. The success oflimb-sparing surgery has also stimulatedtechnological developments in designingand manufacturing endoprostheses torestore function to the damaged limb. Although bone implants have proved Figure 1 Function of the self-actuating extendible endoprosthesis (known as an intercondylar stepless-extension module). Flexure of theeffective in adults1,2, they cause a significant knee joint induces clockwise rotation of a switch unit (a). An angle of flexion of 100 degrees moves a gear wheel (b) via a carrier by 20limb-length discrepancy which precludes degrees; this positioning is held by a spring (c). Rotation of the gear wheel is translated to a threaded spindle (d), which in turn causes atheir use in growing children. Extendible movement of 0.056 mm in a telescopic sleeve higher up the leg (e). An 18-fold repetition of this movement causes an elongation of 1 mm.prostheses have been developed to matchthe growth of the opposite limb, but Despite their drawbacks, the application tissue grows, thereby allowing the kneefrequent surgery was necessary for elonga- of these earlier extendible implants proved more flexure and stimulating the elongationtion procedures, for aseptic loosening of the successful in 13 patients, with definitive mechanism. The number of surgical pro-growing bone, and to correct failure of the limb salvage and equal limb length after cedures needed for the flexion-controlledextension mechanism3–7. In a long-term growth was complete. These are compared device has been reduced (Table 1). A fur-follow-up of uncemented endoprostheses in Table 1 with two patients treated with the ther improvement for children under treat-implanted after tumour resection of the endoprosthesis, in which continuous auto- ment now is the introduction of a centrallower leg in 13 out of 44 children with matic elongation is brought about by camshaft into the implant (Fig. 1), whichgrowth arrest, the final clinical and radio- enforced knee bending9. allows the knee to bend painlessly beyondgraphic results matched those of similarly Overlengthening of the self-extendible the point of elongation (100-degree bend)treated adult patients8. Invasive methods prosthesis is prevented by the tension of the up to an angle of 140 degrees.involving manual, stepwise elongation of surrounding soft tissues, which increases Rainer I. Kotz*, Reinhard Windhager†,the implant also cause scar formation that after each elongation procedure (0.056 Martin Dominkus*, Bernd Robioneck‡,limits motion of the knee joint. mm) and is gradually decreased as the soft Holger Müller-Daniels‡ *Department of Orthopaedics, University ofTable 1 Comparative performance of manually and self-actuating extendible endoprostheses Vienna, Währinger Gürtel 18–20, A-1090 Vienna, Manual device Self-actuating device AustriaAge at resection of tumour (yr) 11.4 (7.3–16.1) 9.3 (6.5–12.1) e-mail: rainer.kotz@akh-wien.ac.atAge at implantation of module (yr) 12.8 (10–18) 12.9 (10.3–15.5) †Department of Orthopaedics, University of Graz,Deficit in leg length at implantation (mm) 12 (0–40) 48 ( 45– 51) Auenbruggerplatz 29, A-8036 Graz, AustriaTotal lengthening after implantation (mm) 84.8 (11–195) 157 (145–169) ‡Stryker Howmedica Osteonics,Step lengthening (mm) 50–100 mm, by surgery 0.138 mm d 1 Professor-Küntscher-Strasse 1-5,Number of operations* 10 (5–25) 7.5 (6–9) D-24232 Schönkirchen, GermanyFollow-up (months) 112.6 (70.6–158.1) 105.2 (100.7–109.7) 1. Chao, E. Y. S. & Sim, F. H. in Tumor Prostheses for Bone and Joint Reconstruction: Design and Application (eds Chao, E. Y. S.Fifteen cases (12 treated for osteosarcoma, 3 for primitive neuroectodermal tumour/Ewing’s tumours) are shown who have suffered growth arrest afterimplantation of either a manual (n 13) or a self-actuating (n 2) growing module. Mean values (and ranges) are shown. & Ivins, J. C.). 335–359 (Thieme, New York, 1983).*Includes surgical procedures for implantation complications. 2. Kotz, R., Ritschl, P. & Trachtenbrodt, J. Orthopedics 9, 1639–1652 (1986).NATURE | VOL 406 | 13 JULY 2000 | www.nature.com © 2000 Macmillan Magazines Ltd 143
  17. 17. brief communications3. Scales, J. T., Sneath, R. S. & Wright, K. W. J. in Limb Salvage 591–599 (Springer, Berlin, 1991). Paper chromatography and high-pres- in Musculoskeletal Oncology (ed. Enneking, W. F.) 52–60 6. Eckardt, J. J. et al. in Limb Salvage: Major Reconstructions in sure liquid chromatography of cyanogens (Churchill Livingstone, New York, 1987). Oncologic and Nontumoral Conditions (eds Langlais, F. &4. Lewis, M. M., Spires, W. P. Jr & Bloom, N. in Limb Salvage Tomeno, B.) 585–590 (Springer, Berlin, 1991). from H. sara and its host plant P. auriculata in Musculoskeletal Oncology (ed. Enneking, W. F.) 606–610 7. Schiller, C. et al. J. Bone Jt Surg. 77B, 608–614 (1995). were followed by specific enzyme tests, 1H- (Churchill Livingstone, New York, 1987). 8. Mittermeyer, F. et al. Clin. Orthoped. (submitted). and 13C-NMR analyses, and mass spec-5, Kotz, R., Schiller, C., Windhager, R. & Ritschl, P. in 9. Windhager, R., Robioneck, B., Bien, M., Müller, H. & troscopy. We compared spectral data from Limb Salvage: Major Reconstructions in Oncologic and Kotz, R. Medizinisch Orthopadische Technik 115, 152–154 Nontumoral Conditions (eds Langlais, F. & Tomeno, B.) (1995). these cyanogens and their tetramethyl- silane–ether derivatives with published spectra for cyanogens of Passifloraceae and related families1,4,5. The primary cyanogensInsect metabolism defence against specialist herbivores such as in P. auriculata were monoglycoside the larvae of Heliconius butterflies. We cyclopentenyl cyanogen, epivolkenin (90%),Preventing cyanide investigated how Heliconius butterfly larvae its diastereomer taraktophyllin (5%) and arelease from leaves process cyanogenic glycosides found in their Passiflora host, a diverse neotropical diglycoside cyclopentenyl cyanogen (5%). Of these, only epivolkenin was sequesteredO rganisms that produce hydrogen genus in which coevolution with Heliconius by H. sara (Fig. 1a). cyanide gas to protect themselves accounts for morphological innovation in We isolated a previously unknown against predators can do so by the some species3. metabolic derivative of epivolkenin, sarau-enzymatic breakdown of a class of com- We examined the fate of five classes of riculatin, from H. sara, which we identifiedpounds known as cyanogens (such as Passiflora cyanogens ingested by Heliconius as (1S, 4R)-1-( -D-glucopyranosyloxy)-4-cyanogenic glycosides)1,2. Here we show larvae by surveying the distribution of hydroxy-2-cyclopentene-1-thiol (Fig. 1b).how a neotropical butterfly, Heliconius sara, cyanogens found in 12 species of Passi- Sarauriculatin was present at a ratio of 1:2can avoid the harmful effects of the floraceae and 14 species of teneral adult with epivolkenin. This new compound wascyanogenic leaves of Passiflora auriculata Heliconius reared on specific hosts. We characterized as a cyclopentenyl cyanogenic(passion vine), on which its larvae feed extracted cyanogens from fresh Passiflo- glycoside that has undergone replacementexclusively. To our knowledge this is the raceae and butterflies and identified them of the nitrile group by a thiol, a metabolicfirst example of an insect that is able to using published procedures1,4,5. reaction that pre-empts the enzymaticmetabolize cyanogens and thereby prevent All butterflies contained aliphatic release of cyanide.the release of cyanide. The mechanistic cyanogens, irrespective of their presence in Conversion of nitrile groups is due todetails of this pathway might suggest new host plants, extending previous findings specific enzymatic action8,9, and conversionways to make cyanogenic crops more useful that these cyanogens are synthesized de of cyclopentenyl cyanogenic glycosideas a food source. novo by Heliconius 6. Most cyanogen classes nitriles to their amides occurs spontaneous- Many organisms, including humans, in hosts were not retained in the butterflies, ly in plant isolates, probably as a result ofpossess enzymes for detoxifying hydrogen nor excreted in larval frass. However, we mixing with enzymes during processing10.cyanide (HCN). Barriers against herbivory found monoglycoside cyclopentenyl cyano- In repeated tests, however, we found sarau-of cyanogenic plants may be more effective gens in all butterflies fed on Passiflora con- riculatin in butterfly but not in plant iso-as a result of the slow or inefficient detoxifi- taining these compounds. Acraea horta, a lates. We conclude that a unique enzymaticcation by the herbivore of HCN or of distant relative of Heliconius, is known to mechanism exists in H. sara for dealingbyproducts of the enzymatic breakdown of sequester a cyclopentenyl cyanogen from with cyanogenic glycosides.cyanogenic glycoside, which generate not Kiggelaria plants7, but we have now demon- Our results show that cyanogen seques-only HCN but also toxic aglycones upon strated cyanogen sequestration in Helico- tration in H. sara must be both selectiveingestion1. Nonetheless, cyanogenesis is no nius. and dynamic, because only one type of host cyanogen is sequestered and this is metabo- a b lized to release valuable nitrogen into the HO HO insect’s primary metabolism. A fuller O O understanding of this process should reveal HO HO O its importance in the nutrition of some HO OH HO O OH species of Heliconius, provide a new per- OH OH spective on Heliconius–Passiflora coevolu- NC H HS H tion, and suggest how agriculturallyFigure 1 Structures of sequestered cyanogen from H. sara. a, Epivolkenin, and b, the corresponding thiol derivative sarauriculatin important cyanogenic plants might be ren-(epivolkenin thiol). Spectral data for epivolkenin: (1S, 4R)-1-( -D-glucopyranosyloxy)-4-hydroxy-2-cyclopentene-1-carbonitrile 1H NMR dered safer and more nutritious for human(250 MHz, CD3OD): aglycone protons at 6.14 (dd, H-2), 6.27 (dd, H-3), 4.81 (m, H-4), 2.25 (dd, H-5A), 3.02 (dd, H-5B), 3J2,3 5.6 Hz, and animal consumption.4 J2,4 1.3 Hz, 3J3,4 2.0 Hz, 2J5A,5B 14.6 Hz, 3J4,5A 4.8 Hz, 3J4,5B 7.1 Hz, -D-glucopyranosyl protons at 4.62 (d, H-1 ), 3.22 Helene S. Engler*, Kevin C. Spencer†,(dd, H-2 ), 3.30–3.40 (m, H-3 , H-4 and H-5 ), 3.68 (dd, H-6 A), 3.86 (dd, H-6 B), 3J1 ,2 7.7 Hz, 2J6 A,6 B 12.0Hz, 3J5 ,6 A 5.5 Lawrence E. Gilbert*Hz, J5 ,6 B 2.0 Hz. C NMR (62.9 MHz, CD3OD): >48.2 (C-5), 62.9 (C-6 ), 75.0 (C-4), 82.3 (C-1), 101.2 (C-1 ), 132.1 and 143.3 2 13 *Section of Integrative Biology, School of Biological(C-2 and C-3), 120.6 (CN), 71.7, 75.0, 78.2 and 78.4 (remaining sugar resonances). NMR spectral data were identical for epivolkenin Sciences, University of Texas, Austin,from P. auriculata. Fast atom bombardment mass spectroscopy (MS (FAB)) m/z 287 [M]+, 286 [M-1]+, 269 [M-H20]+, 260 [M-HCN]+. Texas 78712, USAOptical rotation (D, 589 nm), [ ]25D,+41° (c, 0.0042 g ml 1, in methanol). NMR and optical rotation data were identical for an authentic e-mail: h.engler@mail.utexas.edusample of epivolkenin provided by J. W. Jaroszewski. Spectral data for sarauriculatin: (1S, 4R)-1-( -D-glucopyranosyloxy)-4-hydroxy-2- †Mayertorne Manor, Wendover Dean,cyclopentene-1-thiol. 1H NMR (500 MHz, CD3OD): aglycone protons at 5.96 (dd, H-2), 6.09 (dd, H-3), 4.80 (m, H-4), 1.97 (dd, H-5A), Buckinghamshire HP22 6QA, UK2.88 (dd, H-5B), 3J2,3 5.6 Hz, 4J2,4 1.3 Hz, 3J3,4 2.0 Hz, 2J5A,5B 13.9 Hz, 3J4,5A 4.6 Hz, 3J4,5B 7.3 Hz, -D-glucopyranosyl pro- 1. Spencer, K. C. in Chemical Mediation of Coevolution (ed.tons at 4.5 (d, H-1 ), 3.22 (dd, H-2 ), 3.30–3.40 (m, H-3 , H-4 and H-5 ), 3.68 (dd, H-6 A), 3.84 (dd, H-6 B), 3J1 ,2 = 7.7 Hz, 2J6’A,6’B = Spencer, K. C.) 167–240 (Academic, New York, 1988). 2. Jones, D. A. Phytochemistry 47 (suppl. 2), 155–162 (1998). 12.0 Hz, 3J5’,6’A = 5.5 Hz, 2J5’,6’B 2.0 Hz. 13C NMR (500 MHz, CD3OD): 45.4 (C-5), 62.5 (C-6 ), 75.8 (C-4), 93.3 (C-1), 99.4 (C-1 ), 3. Gilbert, L. E. Sci. Am. 247, 110–121 (1982).134.2 and 141.3 (C-2 and C-3), 71.5, 74.8, 77.8 and 78.0 (remaining sugar resonances). MS (FAB) m/z 294 [M]+, 293 [M-1]+, 276 4. Jaroszewski, J. W., Andersen, J. V. & Billeskov, I. Tetrahedron 43,[M-H20]+.1H and 13C NMR: proton and carbon nuclear magnetic resonance, respectively; chemical shifts are given in (p.p.m.) and 2349–2354 (1987).coupling constants J are expressed in Hertz (Hz). 5. Seigler, D. S. & Brinker, A. M. in Methods in Plant Biochemistry144 © 2000 Macmillan Magazines Ltd NATURE | VOL 406 | 13 JULY 2000 | www.nature.com
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