Topic :Pelvis and Medico legal importance Presenter : Dr. Soreingam Ragui Moderator : Prof. H. Nabachandra
INTRODUCTION• The hip bone ossifies from 3 primary and five sec centres.• The primary centres appear at :• 2nd month IUL : Ilium• 4th month IUL : ischium• 5th month IUL : pubis• At birth the hip bone is ossified, except for three cartilaginous part the iliac crest,the Y – shaped cartilage and a strip along the inferior margin of the bone including the ischial tuberosity.
The pelvis is the region of the bodysurrounded by the pelvic bones and theinferior elements of the vertebral column.• The bony pelvis if formed by four bone.• right and left pelvic bones ( In front and lat)• The sacrum and coccyx ( Behind )• Four joints : two sacroiliac jnts, pubic symphysis ,sacrococcygeal jnt.
• Terms• Pelvic inlet• pelvic inlet is an oblique plane, making an angle of 50 to 60 deg with the horizontal.• Post : Sacral promontory.• Ant : upper margin of pubic symphysis.• On each side : Linea terminalis.• Pelvic outlet• Ant : inferior pubic ligament• Post : coccyx• On each side : Ischiopubic Rami
• Pelvic inlet• Ant post diameter : upper border of symphysis to sacral promontory• Transverse diameter : Widest part of the pelvic brim• Oblique diameter : iliopubic imminence to opp sacrio iliac joint.
• Pelvic index ( Turner ) = a-p or conjugate diam X 100• max trans diam• Three types :• Platypellic = X to 89.9 ( trans oval )• Mesatipellic = 90 to 94.9 ( Rounded )• Dolichopellic = 95 to X ( long oval )• Greulish and thomas :• Four types• 1) Dolichopellic = ap or conj dia more than max trans diam• 2 ) mesatipellic = max tranv dia is equal or exceeds it by no more• than 1 cm.• 3) brachypellic = trans dia exceeds conj dia by 1.1 to 2.9• 4) platypellic = trans dia exceeds conj by 3 cm
• MEDICOLEGAL IMPORTANCE OF PELVIS• Identification• 1) Sex determination.• a) qualitative• b) quantitative• 2) Age determination.• a) anti mortem : Study of ossification of bone.• b) postmortem : Morphology of the symphyseal surface
SEX DETERMINATION1) Qualitative methodBy the study of morphological differences
TRAIT MALE FEMALEPELVIS AS A WHOLE massive,marked muscle site Less massive,smoothSYMPHYSIS higher lowerSUBPUBIC ANGLE V shaped,sharpe angle U shaped,divergent obtuseOBTURATOR FORAMEN Large, often ovoid Small ,traingularACETABULUM Large, tends to direct laterally Small, tend to direct anterolaterrallyGREATER SCIATIC NOTCH Small,close and deep Larger,wider and swallowerISCHIO PUPIC RAMI Slightly everted Strongly evertedSACRIO ILIAC ARTICULATION large Small , obliquePREAURICULAR SULCUS Not frequent More frequent,better developedILIUM High tend to be vertical Low,leterally divergentSACRUM Longer,narower,with more Shorted and broader,with evenly distributed tendency to marked curve at curvature,often 5+segment S1-2 and S3-4,5 seg rulePELVIC BRIM Hearth shaped Circular,ellepticalTRUE PELVIS Relatively smaller Oblique, swallow and spacious
SEX DETERMINATION• Quantitative method• By measuring certain parameters
• Quantitative approach :( INDEX )• Sciatic notch index : width of notch X 100 M=4 to 5• Depth of notch F=5 to 6•• Washburn ischiopubic index :pubic lngth X100,M=73-94• ischial length F=91-115• Coporobasal sacral index:brth of 1st sacrl vertebraX100• brth of base of sacrum• M: 46.2 F:54.3•
AGE DETERMINATION ( POST MORTEM )• By observing the change in the symphyseal surface of the pubic symphysis.
• Age determination : the pubic symphysis is probably the best single criterion in deternmining age in third to fifth decade.• four major contribution are available• 1) Todd. (1923)• 2) Brooks . (1955)• 3) Mckern and Steward (1957)• 4) Suchey and Brooks (1990)
phase Sym surfac Ossific nod Ventral mar Dorsal mar extrimitiesI- (18 to 19 ) Rugged horz none none none No definition grove,fur,ridgeII- (20 to 21 ) Grove filing May appear Ventral sur begins No definition dorsaly n behnd on symp sur bevel beginsIII- ( 22 to 24 ) Ridge n furrow Present Bevel more More difinit No definition progr going almost const prononce dorsal plateauIV- (25 to26 ) Rapidly going present Bevel greatly Complete Lower increased dorsal plateau commencingV- (27 to 30 ) Little change maybe Beginning of Completely Lower cleare vent border defined Upper formingVI- (30 to 35) Granular maybe Vent border Defined Increse define appearnce retain complte upper ,lowerVII- (35 to 40) Texture maybe complete defined Carry on finer,activity dimVIII-(39 to 44) Smooth,no rim maybe No lipping No lipping Oval outline +IX – (44 to 55) Rim present Maybe Iregular No lipping Carry lippedX – (50+) Erosion and BROKEN ----------------- --DOWN-------- ------- erratic ossifi
Female MalePhase mean S.D. 95% range mean S.D. 95% range I 19.4 2.6 < 24 18.5 2.1 < 23 II 25.0 4.9 19-40 23.4 3.6 19-34 III 30.7 8.1 21-53 28.7 6.5 21-46 IV 38.2 10.9 26-70 35.2 9.4 23-57 V 48.1 14.6 25-83 45.6 10.4 27-66 VI 60.0 12.4 > 42 61.2 12.2 > 34
• Comparision:• Todd found no race or sex differences• Steward felt child bearing may be a factor in causing certain symphyseal change and concluded that assesement of age in female by this methods cannot be as accurate as in males .
AGE DETERMINATION (ANTE MORTEM )• by observing the appearance and fusion of the ossification centres with the help of a plain x ray
Bone fusion Galstaun Fleckers Davies and (bengalis) (Australian ) parsons F M F M (Englander s)Crest of illium 17-19 19-20 15-16 18 23Ischium and 8.5 8.5 7 9 28pubisIschial 20 20 20tuberosity
• Conclusion• Pelvic bone is the most important bone for sex determination and also age determination ( in 3rd and 4th decade).• Therefore a meticulous study of the pelvic bone is required in cases where the identity of the person is not know or when the determination of age is required by law enforcing agencies.
• BROOKS, S. (1955). "Skeletal Age at Death: The Reliability of Cranial and Pubic Age Indicators", AJPA 13:567-597.• BROOKS, S and J SUCHEY (1990). Skeletal age determination base on the Os Pubis: A Comparison of the Acsádi-Nemeskéri and Suchey-Brooks Methods." Human Evolution, 5:227-227-238.• TODD, T (1920). "Age Changes in the Pubic Bones, I: The White Male Pubis", AJPA 3: 285-334.• Reddy ,KSN .”the essentian of forensic medicine and toxicology “ 23 edt , 71• Pillay, VV “text book of forensic medicine and toxicology “ 16 edt , 55• Mathiharan,K and amrit k “Modi’s medical jurisprudence and toxicology “ 23 edt , 289