A STUDY ON GOETHE’S OSSICLES IN ADULT HUMAN SKULLS
Int J Pharma Bio Sci 2019 July; 10(3): (B) 181-185Original research articleAnatomyInternational journal of pharma and bio sciencesISSN0975-6299A STUDY ON GOETHE’S OSSICLES IN ADULT HUMAN SKULLSPRIYA.G*Professor and head, Department of anatomy, RVS Dental college and hospital, Kumarankottam campus,Kannampalayam, Sulur, Coimbatore – 641402, Tamil Nadu, India.ABSTRACTThe interparietal part of squamous occipital bone which lies above the highest nuchal line gets ossifiedfrom two centers one on each side. The failure of fusion of ossification centers in this region leads to thedevelopment of interparietal bones or Goethe’s ossicles. These bones are rare in occurrence comparedto the sutural bones in the human skull. The aim of the present study was to observe the variation in theoccurrence of the interparietal bone and the findings were correlated with its ossification. The study wascarried out in 25 adult dried human skulls collected from the Department of Anatomy at RVS DentalCollege and hospital, Coimbatore. The skulls were examined to determine the presence of interparietalbone and if so, any variations in the same. If the interparietal bone was found with variation, it was taggedand separated. Using digitalized camera, those skulls were photographed and studied. Out of 25 skulls,two skulls showed variations, one skull had a large central plate with a small lateral plate. In another skull,a central plate and a left lateral plate of interparietal bone of equal size were observed. These variationsmay be due to non fusion of the ossification centres in the interparietal part of the occipital bone. Thesenonfused plates of bones or ossicles may give a false appearance of fracture in radiological image.Therefore, anatomical knowledge of Goethe’s ossicles in the human skull is useful in the clinical practicefor correct interpretation of skull radiographs to avoid diagnostic errors.KEYWORDS: Interparietal bone, Sutural bone, Lambdoid suture, Transverse suture, Inca bonePRIYA.G *Professor and head, Department of anatomy, RVS Dental college andhospital, Kumarankottam campus, Kannampalayam, Sulur,Coimbatore – 641402, Tamil Nadu, India.Corresponding authorReceived on: 29-05-2019Revised and Accepted on: 18-07-2019DOI: 5Creative commons version 4.0This article can be downloaded from www.ijpbs.netB-181
Int J Pharma Bio Sci 2019 July; 10(3): (B) 181-1857INTRODUCTIONThe interparietal bone is also known as Inca bone or Osincae or Goethe’s ossicles. This bone is present in thesquamous part of the occipital bone. The squamous partof occipital bone consists of two parts, supraoccipitaland interparietal. The interparietal portion may remainseparated from the supraoccipital by a suture calledsuturamendoza and it is then known as the interparietalbone or inca bone. Therefore the true interparietal boneis triangular in shape, bounded by lambdoid and1transverse suture (suturamendoza) .The interparietalbone is considered to be migrated from the parietals oflower animals during evolution to become part of the2occipital bone in man . It was previously known as os3incae, os interparietal or Goethe’s ossicles . Inca boneresembles the triangular architectural monument designof Inca tribes. Inca bones were supposed to be presentin inca tribes in South Andes-America 1200-1597 AD.The members of the royal family of Inca tribe had crownlike configuration on their head. Hence these ossicles4have been known as inca . Embryologically, thesquamous part of the occipital bone above the highestnuchal lines develops into a fibrous membrane and it isossified from two centres. This part of the bone mayremain separate as the interparietal bone. Below thehighest nuchal lines, the squamous part is preformed in5the cartilage and it ossifies from two centres . The uppermembranous part which lies above the highest nuchalline is called the interparietal part. The lowercartilaginous part which extends from the posteriormargin of the foramen magnum up to the highest nuchal6line is called the supraoccipital part . Srivastava (1992)described that the membranous part of occipital bone isossified by three pairs of centres. The first pair ofcentres lies between the superior and highest nuchallines and forms the intermediate segment. The secondpair of centres lies above the highest nuchal lines, oneon each side of the midline and form the lateral plate.The third pair forms the medial plate of the interparietalbone. The intermediate segment never separates fromthe cartilaginous supraoccipital part. The centres andtheir nuclei in the membranous part of the occipital boneabove the supraoccipital part were paired centres. Thendmedial and lateral nuclei of the 2 pair centres will formrdthe lateral plate; upper and lower nuclei of the 3 pair ofcentres will form the medial plate. The two medial platesare separated by the median fissure. The intermediatesegment is separated from the lateral plate by the lateralfissure (Fig.1). Thus, the interparietal bone is formedby the lateral and medial plates together. Failure offusion between these centres or their nuclei with eachother and the supraoccipital part may give rise tovarious anomalies in the interparietal region. Thevariations found in the present study will be explainedbased on srivastava’s description of ossification centres.MATERIALS AND METHODSA total of 25 dried human adult skulls were taken fromthe Department of Anatomy at RVS Dental College andhospital, Coimbatore. The skulls were randomlyselected of unknown age and sex. The broken or partlydamaged skulls were excluded from the study. Onlyclearly demarcated occipital bones were included in thestudy. The skulls were examined for the presence ofinterparietal bones. If the interparietal bone was found, itwas separated from the group. A number tag is tied andkept for the study to avoid confusion. Using digitizedcamera, the tagged skulls were photographed andstudied.RESULTSOut of 25 skulls examined, two skulls showedinterparietal bone. In skull-I, a large central plate with asmall lateral plate of interparietal bone whichaccompanied the latter along its left side. The shape ofthe large central plate was triangular. It more or lessresembled the features of true interparietal bone(srivastava 1992). It was bounded along its apex and onright side by lambdoid suture, left side by vertical sutureand base by a transverse suture. The transverse sutureextends between the lambdoid sutures transversely justabove the external occipital protuberance and superiornuchal line. The vertical suture extends from thelambdoid suture to the transverse suture. The shape ofthe smaller lateral plate of interparietal bone lying on theleft side was also triangular. Its boundaries are mediallyby vertical suture, laterally by lambdoid suture and thebase by transverse suture. In the same skull, numeroussutural or wormian bones were observed in thelambdoid suture. This skull also showed a sutural bonein the sagittal suture above the lambda (Fig.2).In skullII, a central plate and a left lateral plate of interparietalbone of equal size was observed. (Fig.3).This article can be downloaded from www.ijpbs.netB-182
Int J Pharma Bio Sci 2019 July; 10(3): (B) 181-185Figure 1.A schematic diagram of the ossification centres of membranous part of the occipital bone above thendSupraoccipital bone (SO), I- Intermediate segment( ), II-2 pair of centres with medial andrdlateral nuclei( ), III- 3 pair of centres with upper and lower nuclei(x), SNL –Superior nuchal line,HNL – Highest nuchal line, LbS – Lambdoid suture, Lb- Lambda.Figure 2Squamous part of occipital bone shows CIP- Central interparietal bone, LLIP- Left lateralinterparietal bone, TrS-Transverse suture, VrS- Vertical suture, W- Wormian bone,SgS- Sagittal suture,WSgS- Wormian bone in sagittal suture.Figure 3Squamous part of occipital bone shows CIP- Central interparietal bone,LLIP- Left lateral interparietal boneThis article can be downloaded from www.ijpbs.netB-183
Int J Pharma Bio Sci 2019 July; 10(3): (B) 181-185DISCUSSIONThe squamous part of the occipital bone consists of twoparts, supraoccipital and interparietal. These two partsfused to form squamous part of the occipital bone.Sometimes the interparietal part, may remain separatedfrom the supraoccipital by a suture. It is then called thetrue interparietal or inca bone which is bounded bylambdoid suture and suturamendoza (transverseoccipital suture). The occurrence of inca or Goethe’sossicles is rare in humans, In a study of 620 humanskulls, Srivastava found complete separate interparietalbone in 3 skulls with an incident of 0.8%. He found thesuture between the interparietal and supraoccipital parts2cm above the external occipital protuberance and 0.4cm above the superior nuchal line near the lambdoidsuture. He stated that when the interparietal bonedevelops as a separate bone, the suture between it andthe rest of the occipital bone lies at the highest nuchalline. The observations in the present study correlateswith this finding that the interparietal bone found wasseparated from the supraoccipital part by a transversesuture which was along the highest nuchal line. But asmall fragment of bone on the left side was not fusedwith the rest of the bone and so this interparietal bone isnot a true interparietal bone. Though it resembled thecharacteristic features of true interparietal bone (asdescribed by srivastava), a small segment on the leftlateral side remained separate and it couldn’t fulfill therule of true interparietal bone which was a rare finding ofthis study. Similarly according to Srivastava, themembranous portion of the squamous part of occipitalbone develops from three pairs of centres. The first pairof centre forms the intermediate segment which formsthe portion of bone between superior and highest nuchallines and always fuses with the cartilaginoussupraoccipital part. The second and third pair of centersforms the interparietal bone which lies above the highestnuchal line. The second pair forms the lateral plate andthe third pair forms the medial plate. Each centerconsists of a pair of nuclei. He also stated that thebones found in the region of the lambda, lambdoidsuture and sagittal suture, outside the limits of theinterparietal area are sutural or wormian bones, whichdevelop from their own separate ossification centres.The interparietal bone observed in the present study isinterpreted with ossification centres explained bySrivastava. In skull I, there was a large central piece ofinterparietal bone separated by a transverse suture fromthe intermediate segment which lies at the highestnuchal line. In this skull, it seems that the central pieceis formed by the union of upper and lower nuclei of therd3 pair centres and medial nuclei of the 2nd pair centresbut failed to fuse with the first pair centre which formsthe intermediate segment. The small left lateral platendappears to be formed by lateral nuclei of the 2 paircentres which remained separate as they failed to fusewith the rest of the bones. The sutural bones found inthe region of the lambda, lambdoid suture and sagittalsuture which lies outside the limits of the interparietalarea might have developed from their own separateossification centres. In skull II, the interparietal areashowed two independent bones – a central piece and aleft lateral piece. It appears that the central piece isrdformed by the fusion of the 3 pair of centres and thendleft lateral piece by the lateral nuclei of the 2 pair ofcentres which have remained separate. The right lateralndnuclei and the medial nuclei of the 2 pair of centreshave fused with each other and with the supraoccipital7part . Malhotra et al reported a single large interparietalbone with large number of wormian bones in the region8of lambdoid suture . Keith stated that a separate singleinterparietal bone in man is an extremely rare anomaly.He observed that phylogenetically, the interparietalsfuse with the parietals in marsupials, ruminants andungulates, while in rodents, they fuse both with occipitaland parietal bone. In primates and carnivores as in man,they fuse with occipital. But sometimes as a variant in9.man, the interparietal is seen as a separate boneNikolova et al reported os incae central (central piece)and os incae lateral sinistrum (lateral piece) in Bulgarianpopulation. They stated that the lower border of theinterparietal bone or at least one section of it should beat the level of the highest nuchal line or slightly above it10. Hanihara and Ishida classified about five differenttypes of os incae.According to their classification, theinterparietal bone found in the present study falls under11type II and III inca bones . A recent study in thepopulation of south coastal area of Andhra Pradesh inIndia, has reported the presence of interparietal bones12in 8(9.5%) skulls out of 84 skulls . Neeru Goyal et alfound interparietal bone on the right side (dextraasymmetric bipartite occipital bone) in 2 cases out of13150 skulls . Yucel et al reported os incae lateralsinistrum and they stated that it may be due to failure ofndfusion of lateral nucleus of the 2 pair with the rest of14the interparietal bone . In the present study, theinterparietal bones are found in 2 skulls out of 25 skullswhich may not be an appropriate percentage ofincidences due to small sample size. Goethe’s ossiclesmay give a false appearance of fracture onroentgenographs.Suchbonesmayleadtocomplications during burr-hole surgeries and theirextensions may lead to continuation of fracture lines.Due to clinical implication, the documentation ofpresence and number of fragments of ossicles isessential though it is a common variation in theinterparietal region.CONCLUSIONIt is concluded that the interparietal bones can appear invarious forms and shapes depending on the failure offusion of ossification centres and their nuclei in theinterparietal region. Knowledge of Goethe’s ossicles inthe human skull may be useful in the clinical practice forcorrect interpretation of skull radiographs to avoiddiagnostic errors, procedures like craniotomy and fortheir future reference.CONFLICT OF INTERESTConflict of interest declared noneThis article can be downloaded from www.ijpbs.netB-184
Int J Pharma Bio Sci 2019 July; 10(3): (B) 181-1858.REFERENCES1.2.3.4.5.6.7.Yogesh A, Pandit S, Joshi M, Trivedi G, MaratheR. Inca - interparietal bones in neurocranium ofhuman skulls in central India. J Neurosci inivasan SU and JK. Interparietal (Inca) bone: acase report. Int J Anat Var. 2011;4:90–2.Available from: etal-inca-bone-a-case-report.htmlWilliams, P.L., Bannister, L.H., Berry, M.M.,Collins, P., Dyson M. Gray’s anatomy. 38th ed.London: Churchill Livingstone; 1995. 583–606 ReferenceID 950471Earle T, Moseley ME. The Incas and TheirAncestors: The Archaeology of Peru. /10.2307/2804246Standring S. Grays anatomy. The anatomicalbasis of clinical practice. 39th ed. Elsevier,Churchill livingstone; 2006. 465 p.AK D. Essentials of human anatomy head & neck.5th ed. Current Books International; 2013. 9 p.HC S. Ossification of the membranous portion ofthe squamous part of the occipital bone in man. JAnat. 1992;180(Pt 2):219. Available 1259666/9.10.11.12.13.14.Malhotra VK, Tewari PS, Pandey SN, Tewari SP.Interparietal bone. Cells Tissues doi.org/10.1159/000144953Keith.A. Human embryology and morphology. 6thed. London: Edward Arnold; 1948. 212–24 p.Nikolova S, Toneva D, Yordanov Y, Lazarov N.Variations in the squamous part of the occipitalbone in medieval and contemporary cranial seriesfrom Bulgaria. Folia Morphol (Warsz) //dx.doi.org/10.5603/fm.2014.0055Hanihara T, Ishida H. Os incae: variation infrequency in major human population groups. JAnat. 2001;198(2):137–52. Available 20137.xBhanu PS SK. Interparietal and pre-interparietalbones in the population of south coastal AndhraPradesh, India. Folia Morphol. .viamedica.pl/folia morphologica/article/view/19300GoyAl N, GuptA M AggaB. A study of theinterparietal bones. J Clin Diagn 7f135266f2.pdf? ga 272Yücel F, Eğilmez H AZ. A study on theinterparietal bone in man. Turkish J Med Sci.1998;28(5):505–10.This article can be downloaded from www.ijpbs.netB-185
Int J Pharma Bio Sci 2019 July; 10(3): (B) 181-185 Original research article This article can be downloaded from www.ijpbs.net B-181 Anatomy International journal of pharma and b
Goethe-Zertifikat A1 Goethe-Zertifikat A2 Goethe-Zertifikat B1 Goethe Zertifikat B2 Goethe Zertifikat C1 Goethe Zertifikat C2 Goethe Institut Start Deutsch 1(SD 1) Fit in Deutsch 1 (Fit 1) Start Deutsch 2 (SD2) Fit in Deutsch 2 (Fit 2) BULATS 49-59 punts* ZDfB (Zertifikat Deutsch für den Beruf) ZDf
GOETHE-ZERTIFIKAT A2 exam for adults and the GOETHE-ZERTIFIKAT A2 FIT IN DEUTSCH exam for young learners are an integral part of the Goethe-Institut’s most-up-to-date version of the Exam Guidelines. Die Prüfungen GOETHE-ZERTIFIKAT A2 und GOETHE-ZERTIFIK
Zertifikat A2 Goethe-Zertifikat B1 Goethe-Zertifikat B2. Goethe-Zertifikat C1. Goethe-Zertifikat C2 Großes Deutsches Sprachdiplom (GDS) Start Deutsch 2 (SD 2) Zertifikat Deutsch (ZD) Fit in Deutsch 1 (Fit 1) Fit in Deutsch 2 (Fit 2) Goethe-Zertifikat
Prüngstraining Goethe-Zertifikat C1 Übungsbuch, mit Audio CD Berlin : Cornelsen Verlag Goethe-Zertifikat C2 Fit fürs Goethe-Zertifikat C2 : Großes Deutsches Sprachdiplom mit Audio CD Linda Fromme; Julia Guess Ismaning : Hueber, 2012 Mit Erfolg zum Goethe-Zertifikat C2: G
Sep 01, 2018 · GOETHE-ZERTIFIKAT A1: START DEUTSCH 1 GOETHE-ZERTIFIKAT A2 GOETHEGOETHE-ZERTIFIKAT B1 GOETHEGOETHE-ZERTIFIKAT B2 (bis 31.07.2019) GOETHE-ZERTIFIKAT B2 (modular, ab 01.01.2019 an ausgewählten Prüfungszentren, ab 01.08.2019 weltweit) wide)GOETHE-ZERTIFIKAT
Goethe’s Theory of Colours Jung was familiar with Goethe’s influential Theory of Colours (1810), included in the poet’s scientific writings. He cited Eckermann’s Conversations with Goethe, which contain numerous discussions on Goethe’s colour theories, in his dissertation, and quoted Goethe’s
DIE PRÜFUNGEN DES GOETHE-INSTITUTS THE EXAMS OF THE GOETHE-INSTITUT PRÜFUNGSORDNUNG EXAM GUIDELINES Stand: 1. September 2020 Last updated: September 1, 2020
Institució/Organisme A1 A2 B1 B2 C1 C2 Goethe Institut Goethe Goethe-Zertifikat A1: Start Deutsch 1(SD 1) Fit in Deusch 1 (Fit 1) -Zertifikat A2: Start Deutsch 2 (SD2) Fit in Deutsch 2 (Fit 2) BULATS 20-39 punts Zertifikat B1 BULATS 49-59 punts Goethe Zertifikat B2 ZDfB (Zertifikat Deutsch für den Beruf)
