Anatomy of the hip: correlation of coronal and sagittal cadaver cryomicrosections with magnetic resonance images

UCLA UCLA Previously Published Works Title Anatomy of the hip: correlation of coronal and sagittal cadaver cryomicrosections with magnetic resonance images. Permalink https://escholarship.org/uc/item/3vp19897 Journal Surgical and radiologic anatomy : SRA, 13(4) ISSN 0930-1038 Authors Bassett, LW Ullis, K Seeger, LL et al. Publication Date 1991 DOI 10.1007/bf01627762 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Surgical °2 Radiolog,c Anatomy Surg Radiol Anat (1991) 13 : 301-306 Journal of Clinical Anatomy © Springer-Verlag 1991 Radiological anatomy Anatomy of the hip: correlation of coronal and sagittal cadaver cryomicrosections with Magnetic Resonance Images LW Bassett 1, K Ullis 2, LL Seeger 1, and W Rauschning 3 Departments of Radiological Sciences 1 and UCLA Student Health Service 2 and Department of Pediatrics 2, UCLA School of Medicine, 10833 Le Conte Avenue, Los Angeles, CA 90024-1721, USA and the Department of Orthopedic Surgery 3, Academic University Hospital, Uppsala, Sweden S u m m a r y . Magnetic r e s o n a n c e imaging (MRI) is noninvasive and provides images with higher soft tissue contrast than possible with any other imaging modality. Unlike CT which depicts anatomy in the axial plane, MRI is capable of producing images in thin cross sections acquired directly in any plane, usually axial, coronal or sagittal planes. The use of diagnostic MR images is facilitated by an understanding of the detailed anatomy that is depicted. The purpose of this study was to identify anatomical structures in coronal and sagittal cryomicrosections of the hip region. Thin cryosections of the hips of fresh-frozen cadavers were obtained by a method developed by one of the authors (WR). These sections were matched with thin-section, high resolution MR images of a normal volunteer. The complex anatomy of the hip and its surrounding muscles, tendons and ligaments was exquisitely depicted on both the cadaver microcryosections and the matched MRT images. Offprint requests : LW Bassett Anatomie de ia hanche : correlation entre les microsections et les r~sultats de l'imagerie en r~sonance magn~tique R~sum~. L'imagerie en r6sonance magn6tique (IRM) est une technique non invasive qui permet d'obtenir des images des parties molles avec un contraste plus 61ev6 que toutes les autres techniques. A la diff6rence du scanner qui d6cfit l'anatomie dans le seul plan axial transverse, I'IRM est capable de donner des images en coupes fines obtenues directement dans n'importe quel plan : couramment dans les plan axial, transverse et sagittal. L'interpr6tation des images IRM est facilitde par la compr6hension de l'anatomie d6taill6e de la r6gion 6tudi6e. Le propos de ce travail est d'identitier les structures anatomiques dans des plans de coupes sagittales et coronales de la r6gion de l'articulation coxo-f6morale. Des coupes fines de pi~ces congel6es ont 6t6 obtenues ~ partir de douze cadavres selon une m6thode mise au point par l'un des auteurs (WR). Ces sections ont 6t6 compar6es avec des coupes IRM fines faites en haute r6solution chez un volontaire sain. L'anatomie c o m p l e x e de la hanche et des muscles qui l'entourent ainsi que des tendons et des ligaments est d6crite avec pr6cision sur les coupes anatomiques et les images IRM. Key words: Hip - - Anatomy - Cryomicrotomy - Magnetic resonance imaging Magnetic resonance imaging (MRI) has several advantages over other methods in the depiction of the anatomy of the musculoskeletal system [7, 9, 12, 16]. Cross-sectional anatomy of the hip joint in the axial plane has been correlated with CT images [4, 6, 8,13-15]. CT is capable of producing thin section images, with higher soft tissue contrast than conventional radiography. CT images, acquired directly in the axial plane, have proven useful in the evaluation of fractures around the hip joint [13]. Due to the different MR signal intensities of fat and bone marrow, j o i n t fluid, muscles, tendons and ligaments, and blood vessels, MR imaging provides 302 LW Bassett et al : Anatomy of the hip Table 1. Signal characteristics of muscul o s k e l e t a l t i s s u e s in T l - w e i g h t e d MR images Caract6ristiques des signaux des tissus de l'appareil musculo-squelettique en s6quence pond6r6e T1 Tissue Signal Characteristics Cortical bone Ligaments, tendons Fibrocartilage Normal fluid Muscle Hyaline cartilage Fat (including marrow) Void Void Void Low Intermediate Intermediate High higher soft-tissue contrast than CT (Table 1). As a result, MRI is proving useful in the evaluation of tumors, trauma and infection involving joints, muscles and tendons, and it is an extremely sensitive indicator of bone marrow abnormalities [1, 2, 5, 16, 17]. Unlike CT, thinsection MR images can be acquired directly in coronal, sagittal or any oblique planes, as well as in the axial plane. In order to better understand the anatomy of the hip in coronal and sagittal images, we acquired thinsection, high-resolution MR images of the hip of a normal volunteer and correlated the anatomy with matched cadaver cryomicrosections. Figs. 1-4 Figs 1-4 are coronal cryomicrosections and MR images arranged from anterior to posterior. 1 Coronal cryomicrosection (A) and matched MR image (B) at the level of the anterior aspect of femoral head. The femoral artery and its branches are filled with red pigment in the cadaver section and the bladder contains a dark blue pigment. In the MR image, the external iliac vessel is seen as a signal void and the thick fibrous capsule of the hip also has no signal. The cortical bone of the superior pubic ramus is a signal void but the bone marrow has a high signal intensity. The symphysis pubis is at the left side of the image. The muscles have intermediate signal intensity, and their locations can be identified although the borders of each muscle cannot always be defined in the MR image 2 Coronal cryomicrosection (A) and MR image (B) at the midportion of the femoral head and neck. The femoral head marrow has high signal intensity except at three localized regions: the fovea capitis, the horizontally oriented physeal scar (arrow), and the prominent trabeculae in the lines of stress. The medial aspect of the hip joint is identified by the acetabular tear drop. The profunda femoris a. can be seen in both the cryomicrnsection and the MR image. The musculotendinous junction of the gluteus minimus can be identified in the MR image where the signal intensity changes from an intermediate intensity to a signal void. The internal and external branches of the iliac artery are identified at the top of the MR image. The hyaline cartilage can be identified as an intermediate signal intensity structure lying between the signal void of the cortical and acetabular cortical bone 3 Coronal cryomicrosection (A) and MR image (B) at the level of the anterior aspect of the lesser trochanter. The course of the obturator externus m. and its tendon is seen, from its origin (on the margin of the obturator foramen) to its tendinous insertion (at the posterior aspect of the hip joint along the digital fossa of the femur). The gluteus minimus is seen with its tendon inserting on the greater trochanter 4 Coronal cryomicrosection (A) and MR image (B) at the most posterior aspect of the greater and lesser trochanter. Three of the muscles that insert on the posterior aspect of the greater trochanter, the piriformis, superior gamellus and inferior gamellus can be distinguished in both the cryomicrosection and the MR image Material and Methods The cryomicrosections were obtained using a method developed in Sweden by one of the authors (WR) [9, 11]. In order to aid in their identification, the arteries of fresh cadavers were injected with a red pigmented barium compound with pulsatile, hypersystemic pressure prior to freezing. This injection forced all blood into the venous sytem, slightly distending the veins. The b l a d d e r was i n j e c t e d with blue-tinted saline. The region of interest was resected with an oscillating band saw, embedded in a car- Les figures 1 h 4 sont des coupes coronales, elles sont class6es d'avant en arfi~re. Coupe anatomique : A, coupe IRM : B. 1 Coupe passant par le p61e ant6rieur de la t&e fdmorale. L'a. f6morale et ses branches sont color6es en rouges sur la coupe cadav6rique, la vessie est color6e en bleu fon~6. En IRM les vaisseaux iliaques externes sont repr6sent6s par un signal vide, l'6paisse capsule articulaire de l'articulation coxo-f6morale n'a pas, elle non plus de signal IRM. L'os cortical de la branche ilio-pubienne a un signal nul, la moelle osseuse par contre poss~de un signal 61ev6. La symphyse pubienne se situe ~ gauche de l'image, les muscles poss~dent un signal interm6diaire, il peuvent ~tre localis6s bien que leur limites ne soient par parfaitement d6finies en IRM 2 3 coupes passant par la portion moyenne de la t~te et du col f6moral. La moelle de la t~te f6morale poss6de un signal 61ev6 sauf dans trois r6gions pr6cises: la fossette du ligament rond, le reliquat du cartilage 6piphysaire (fldche) et les lignes de force de l'os spongieux. La face interne est identifi6e grace au sourcil cotyloidien. L'a. f6morale profonde est visible sur les deux coupes. La jonction musculo tendineuse du petit fessier peut ~tre identifi6e sur la coupe IRM par le changement de signal qui d'interm6diaire devient vide. Les branches interne et externes de ra. iliaque sont identifiables en haut de l'image IRM. Le cartilage hyalin est visible sous forme d'un signal interm6diaire situ6 entre le signal vide de la corticale de la t~te f6morale et l'os cortical ac6tabulaire 3 Coupes passant juste en avant du petit trochanter. On peut voir le trajet de l'obturateur externe et son tendon depuis son origine au foramen obtur6 jusqu'h son insertion darts la fossette digitale du f6mur 4 Coupes passant juste en arribre du grand et du petit trochanter. Trois des muscles qui s'ins~rent ~ la face post6rieure du grand trochanter peuvent ~tre vus : le piriforme, le jumeau sup6rieur et le jumeau inf6rieur LW Bassett et al : Anatomy of the hip 303 304 LW Bassett et al : Anatomy of the hip LW Bassett et al : Anatomy of the hip 305 b o x y m e t h y l c e l l u l o s e gel, a n d t h e n t r a n s f e r r e d to a h e a v y d u t y s l e d g e c r y o m i c r o t o m e for s e c t i o n i n g . T h e frozen specimens were cryoplaned at 2 0 to 4 0 m i c r o n intervals. A specially d e s i g n e d c a m e r a s t a n d w h i c h a t t a c h e d to t h e k n i f e h o l d e r p r o v i ded stable sequential photography of the surfaces of the cryoplaned s p e c i m e n . T h e size o f the c a d a v e r s p e c i m e n s w a s l i m i t e d b y the 16 c m b y 45 c m d i m e n s i o n s o f the e m b e d ding frame. MR images of a normal volunt e e r w e r e a c q u i r e d u s i n g a 0.3 T iron-core resistive magnet (Fonar, M e l v i l l e , N e w York). E a c h c o r o n a l a n d sagittal M R i m a g e h a d a 7 m m Figs. 5-8 Figures 5-8 are sagittal cryomicrosections and MR images arranged from medial to lateral 5 Sagittal cryomicrosection (A) and MR image (B) medial to the acetabulum, at the origin of the obturator internus on the ischial ramus. The external iliac a. is identified in the microcryosection by the red dye in its lumen and in the MR image by the tubular signal void of the rapidly flowing blood in its lumen 6 Sagittal cryosection (A) and MR image (B) at the level of the acetabular fossa. The femoral artery is visualized at the level of its bifurcation into deep and superficial branches. In the MR image, the two parts of the iliopsoas m., the psoas and iliacus muscles are clearly seen 7 Sagittal cryomicrosection (A) and MR image (B) at the midsection of the femoral head. The sartorius m. is seen most anteriorly. The anterior inferior iliac spine, site of origin of the rectus femoris is seen above the hip joint. The hyaline cartilage has intermediate to high signal intensity in the MR image. The thicker trabeculae of the femoral head are seen as low signal intensity structures within the high signal of the bone marrow 8 Sagittal cryomicrosection (A) and MR image (B) at the level of the femoral neck, near the greater trochanter. The distal aspects of the muscles and tendons of the piriformis, superior gemellus, inferior gemellus and obturator internus are identified near their insertions on the superior border of the greater trochanter Les figures 5 ~ 8 sont des coupes dans plan sagittal, elles sont classres d'arri~re en avant 5 La coupe passe par la partie interne de l'acrtabulum ~ rorigine de l'obturateur interne et de la branche ilio-pubienne. L'a. iliaque externe est identifire sur la coupe anatomique par la coloration rouge et sur I'IRM par un signal nul de forme tubulaire du au flux sanguin rapide 6 La coupe passe an niveau de la fossette acrtabulaire. L'a. frmorale est visualisre au niveau de sa bifurcation. Sur les images IRM les deux portions dum. iliopsoas sont bien individualisres 7 Coupe passant par le milieu de la t~te frmorale. Le m. couturier est le plus antrrieur. L'rpine iliaque antrro-infrrieure, site d'insertion du droit frmoral surplombe rarticulation coxofrmorale, le cartilage hya!in poss~de un signal intermrdiaire, les travres les plus 6paisses de la t~te frmorale sont vue sous forme d'un signal de faible intensit6 au sein du signal 61ev6 de la moelle osseuse 8 Coupe passant au niveau du col frmoral proche du grand trochanter. Les extr~mitrs distales des corps et des tendons des mm. piriforme, jumeau suprrieur et infrrieur ainsi que robturateur interne sont identifiables ~t proximit6 de leurs insertions au bord supdrieur du grand trochanter Key to abbreviations used in Figures. A acetabulum Ad adductor mm. AdM adductor magnus m. AIIS anterior inferior iliac spine AT acetabular tear drop B bladder C capsule of hip joint Ela external iliac a. Ely external iliac v. Elav external iliac a. and v. EO external oblique m. F fovea Fa femoral a. FN femoral neck G gemellus m.Ga gluteal a.Gav gluteal a. and v. GMd gluteus medius m.GMn gluteus minimus m. GMx gluteus maximus m. GT greater trnchanterGv gluteal v. H hamstring m. group HC hyaline cartilage I ilium llav Internal iliac a./v. Hv Internal iliac v. Iva Iliac v. and a. IG inferior gemellus m. 1Pt Iliopsoas tendon I 0 internal oblique m. Im iliacus m. 1P iliopsoas m. IPR inferior pubic ramus Is ischium L labrum LT Lesser trochanter It ligamentum teres OE obturator externus m. Ol obturator internus m. Olt obturator internus tendon Pi piriformis m. Pit piriformis tendon Pc pectineus m. PF profunda femoris a. QF quadratus femoris m. R rectus abdominus m. RF rectus femoris m. S sartorius m. Sc sacrum SG superior gemellus m. SI sacroiliac joint SP symphysis pubis SPR superior pubic ramus T trabeculae V vastus medialis mm. VL vastus lateralis m. t h i c k n e s s a n d w a s a c q u i r e d at 10 mm intervals using a relatively T1weighted pulse sequence (Spin Echo: 700 0.75 mm by 0.75 mm pixel size). T h e field o f v i e w for the MR images was 20 cm by 20 cm. Results F i g u r e s 1-4 s h o w the c o r o n a l cryomicrosections and matched MR i m a g e s , f r o m a n t e r i o r to p o s t e r i o r . F i g u r e s 5-8 s h o w the sagittal cryomicrosections and matched MR images, from medial to lateral. M R i m a g e s d e p i c t e d the n o r m a l anatomy of the hip with excellent d e t a i l . In p a r t i c u l a r , m u s c l e s a n d their tendinous insertions could be identified in coronal and sagittal planes. T h e M R a p p e a r a n c e o f the b o n y s t r u c t u r e s w a s as e x p e c t e d : cortical b o n e h a d n o s i g n a l ( b l a c k ) and the marrow had a very bright s i g n a l ( w h i t e ) o n this T l - w e i g h t e d p u l s e s e q u e n c e ( T a b l e 1). T h e h i p capsule, l i g a m e n t s a n d t e n d o n s h a d v e r y l o w to a b s e n t s i g n a l intensity, which allows for their differentiation from adjacent muscles, which have intermediate signal intensity. B l o o d v e s s e l s w e r e s e e n as s i g n a l v o i d d u e to the r a p i d f l o w i n g blood. Hyaline cartilage had intermediate to high signal intensity in the 306 images, allowing its differentiation from the adjacent cortical bone of the acetabulum and femoral head which was seen as a signal void. Discussion Today, one of the major clinical applications of the study of gross anatomy is the correlation with diagnostic images [4, 7-9, 11-15]. The study of anatomy has become more complex as new imaging modalities have created a need to evaluate high-resolution cross-sectional images performed in multiple planes. CT depicts anatomy directly in the axial plane, and the widespread use of CT has resulted in greater familiarity with cross-sectional anatomy in this plane. In addition to the axial plane, coronal and sagittal planes are frequently utilized for MRI, and MR images can be acquired directly in virtually any plane. The high soft-tissue contrast of MR images allows for the better distinction between soft-tissue structures such as bone marrow, joint fluid, and ligaments and tendons (Table 1). MRI can be a useful diagnostic tool for evaluation of abnormalities in the region of the hip joint, inclu- LW Bassett et al : Anatomy of the hip ding ischemic necrosis of the femoral head, tumors, infection, and injuries [1]. MRI has been shown to be useful in understanding the complex anatomy of the neonatal hip [3]. Hopefully, these matched cryomicrosections and MR images will be useful as an anatomical reference guide when evaluating the hip joint with diagnostic MR images. 8. 9. 10. 11. References 1. Bassett LW, Gold RH (1988) Magnetic resonance imaging of the musculoskeletal system: an overview. Clin Orthop 244 : 17-28 2. Beltran J, Noto AM, Herman LJ, Lubber LM (1987) Tendons: High-field-strength, surface coil MR imaging. Radiology 162 : 735-740 3. Bos CFA, Verbout AJ, Bloem JL, van Leeuwen MBM (1990) A correlative study of MR images and cryosections of the neonatal hip. Surg Radiol Anat 12 : 43-51 4. Clark JM, Haynor DR (1987) Anatomy of the abductor muscles of the hip as studied by computed tomography. J Bone Joint Surg [Am] 69 : 1021-1031 5. Demas BE, Heelan RT, Lane J, Marcove R, Hajdu S, Brennan MF (1988) Soft tissue sarcomas of the extremities: Comparison of MR and CT in determining the extent of disease. AJR 150 : 615-620 6. Harley JD, Mack LA, Winquist RA (1981) CT of acetabular fractures: comparison with conventional radiography. AJR 138 : 413-417 7. Holliday J, Saxon R, Lufkin RB, Rauschning W, Reicher M, Bassett L, Hanafee W, Barbaric Z, Sarti D, Glenn W Jr 12. 13. 14. 15. 16. 17. (1985) Anatomic correlations of magnetic resonance images with cadaver cryosections. Radiographics 5 : 887-921 Ledley RS, Huang HK, Mazziotta JC (1977) Cross-sectional anatomy--an atlas for computerized tomography. Williams & Wilkins, Baltimore Lufkin R, Rauschning W, Seeger L, Bassett L, Hanafee W (1987) Anatomic correlation of cadaver cryomicrotomy with magnetic resonance imaging. Surg Radiol Anat 9 : 299-302 Mink JH, Reicher MA, Crues JV III (1987) Magnetic Resonance Imaging of the knee. Raven Press, New York Rauschning W (1983) Computed tomography and cryomicrotomy of lumbar spine specimens: a new technique for multiplanar anatomic correlation. Spine 8 : 170-180 Reicher MA, Rauschning W, Gold RH, Bassett LW, Lufkin RB, Glenn W Jr (1985) High-resolution magnetic resonance imaging of the knee joint: normal anatomy. AJR 145 : 895-902 Rubenstein J, Kellam J, McGonigal D (1983) Cross-sectional anatomy of the adult bony acetabulum. J Can Assoc Radiol 34 : 16-18 Saks BJ (1986) Normal acetabular anatomy for acetabular fracture assessment: CT and plain film correlation. Radiology 159 : 139-145 Schilling JF, Wechsler RJ (1986) Computed tomographic anatomy of the buttock. Skeletal Radiol 15 : 613-618 Seeger LL, Ruszkowski JT, Bassett LW, Kay SP, Kahmann RD, Ellman H (1987) MR imaging of the normal shoulder: Anatomic correlation. AJR 148 : 83-91 Tang JS, Gold RH, Bassett LW, Seeger LL (1988) Musculoskeletal infection of the extremities; evaluation with MR imaging. Radiology 166:205-209 Received March 20, 1991/Accepted in final form September 9, 1991