|
|
|
|
TibiaGeneral features. The tibia is the medial and much the stronger of the two bones of the leg, and, excepting the femur, is the longest bone of the skeleton. It is prismoid in form, and possesses a shaft and two ends. Its lower end, though large, is smaller than the upper end, and on its medial side a stout process, termed the medial malleolus, projects downwards beyond the rest of the bone. The anterior border of the shaft forms a conspicuous sharp crest, which curves medially at the lower end towards the medial malleolus ; it is the most prominent of the three borders. The student should now be able to refer a given tibia to its correct side. The upper end of the tibia is expanded, especially in its transverse axis, to provide a good bearing surface for the lower end of the femur. It comprises two prominent masses, named the medial and lateral condyles, and a smaller projection, termed the tubercle of the tibia. The condyles project backwards a little, so as to overhang the upper part of the posterior surface of the shaft, and superiorly each is covered by an articular surface, the two being separated by an irregularly roughened intercondylar area. The medial condyle is the larger but does not project so much as the lateral condyle. Its upper articular surface (fig. 469), oval in outline, is concave in both diameters, and its lateral border projects upwards, deepening the concavity and covering an elevation, termed the medial intercondylar tubercle. The posterior surface of the condyle is marked, immediately below the articular margin, by a transverse roughened groove. Its medial and anterior aspects form a rough strip, separated from the anterior surface of the shaft by an inconspicuous ridge.
 The lateral condyle overhangs the shaft, especially at its posterolateral part, which bears on its inferior surface a small circular facet for articulation with the upper end of the fibula. The upper aspect (fig. 469) is covered by the articular surface for the lateral condyle of the femur. Nearly circular in outline, it is slightly hollowed in its central part, and its medial border projects upwards to cover an elevation, termed the lateral intercondylar tubercle. The posterior, lateral and anterior aspects of the condyle are rough. The anterior surfaces of the two condyles become continuous in front with a large triangular area, the apex of which is directed downwards and is formed by the tubercle of the tibia. The lateral edge of this area forms a sharp ridge which separates the lateral condyle from the lateral surface of the shaft. The intercondylar area (fig. 469) forms a roughened strip on the superior surface which intervenes between the articular surfaces of the two condyles. It is narrowest at its central part, where it is marked by an elevation, termed the intercondylar eminence. The lateral and medial parts of the eminence project slightly upwards, and constitute the lateral and medial intercondylar tubercles. Both behind and in front of the eminence the intercondylar area becomes wider, as the curved margins of the articular surfaces recede from each other. The tibial tubercle is placed at the upper end of the anterior border of the shaft, and at the truncated apex of the triangular area on the front of the bone where the anterior surfaces of the two condyles become continuous. It forms a low eminence, divided into a lower roughened and an upper smooth portion. The lower part can be felt through the skin, from which it is separated only by a bursa, termed the sub-cutaneous infrapatellar bursa ; the upper part gives attachment to the ligamentum patella. Particular features.-The articular surface of the medial condyle is oval in shape, with its long axis anteroposterior. It is related around its anterior, medial and posterior margins to the medial semilunar cartilage (medial meniscus)- and the area of contact is flattened. The imprint of the cartilage, which is widest behind and narrower at the medial side and in front, can often be recognized on the bone. The rest of the surface is concave, and its raised lateral margin covers the medial intercondylar tubercle. The articular surface of the lateral condyle is more nearly circular in shape. Like the medial articular surface it is related to, and bears the flattened imprint of, the corresponding semilunar cartilage. Elsewhere the surface is very slightly concave to adapt it to the surface of the corresponding femoral condyle. and its raised medial margin is continued on to the lateral aspect of the lateral intercondylar tubercle. The edges of the two articular surfaces are sharp except at the posterior part of the lateral surface, where the margin is smooth and rounded ; in this situation the tendon of the popliteus is intimately related to the bone. The anterior and lateral margins of the lateral surface and the anterior, medial and posterior margins of the medial surface give attachment to the coronary ligaments. The intercondylar area (fig. 470) is widest anteriorly. In its anteromedial part, just in front of the medial articular surface, it bears a slight depression which gives attachment to the anterior horn of the medial semilunar cartilage. Behind that depression a relatively smooth area affords attachment to the lower end of the anterior cruciate ligament. The anterior horn of the lateral semilunar cartilage is attached to the bone in front of the intercondylar eminence and lies lateral to the anterior cruciate ligament. The intercondylar eminence occupies the narrow central part of the area, and is surmounted by two tubercles, of which the medial is slightly the more prominent. The posterior slope of the eminence gives attachment to the posterior horn of the lateral semilunar cartilage, and behind that the intercondylar area inclines downwards and backwards. A depression behind the base of the medial intercondylar tubercle gives attachment to the posterior horn of the medial semilunar cartilage. The rest of the area is smooth and affords attachment to the lower end of the posterior cruciate ligament, as far back as the ridge to which the capsular ligament is attached. The groove on the posterior aspect of the medial condyle receives the insertion of the semimembranosus muscle ; its upper border receives the capsular, and its lower border the posterior and shorter fibers of the medial ligament of the knee-joint. The medial and anterior surfaces of the condyle, which are pitted by numerous vascular foramina, give attachment to the medial patellar retinaculum. The fibular facet on the lateral condyle is directed downwards and slightly backwards and laterally. Above and to its medial side the posterior aspect of the condyle is grooved by the tendon of the popliteus. but a bursa intervenes between the tendon and the bone. The lateral and anterior aspects of the condyle are separated from the lateral surface of the shaft by a sharp margin, which gives attachment to the deep fascia of the leg. An impression on the anterior surface, often well-marked though flattened affords attachment for the iliotibial tract. Near the fibulas facet the uppermost fibers of the extensor digitorum longus and peroneus longus arise from the lateral surface. The tibial tubercle is subcutaneous in its lower part only ; its upper part receives the attachment of the ligamentum patellae. The two areas are sometimes separated by a rough crest, which receives the superficial fibers of the ligament. Above the tubercle the bone is related to the deep surface of the ligament, but the deep infrapatellar bursa and some fabrofatty tissue intervene. The shaft of the tibia (figs. 471, 473) is triangular on section, and possesses medial, lateral and posterior surfaces, separated by anterior, interosseous and medial borders. It is thinnest at the junction of its middle and lower thirds, but expands considerably towards its upper and lower ends. The anterior border commences at the tibial tubercle and runs downwards to the medial malleolus. It is subcutaneous throughout its whole length, and, except in its lower fourth, where it is rounded and indistinct, forms a sharp crest, which is familiarly known as the 'shin bone.' It is not straight, but follows a slightly sinuous course and its lower fourth diverges towards the medial side. The interosseous border commences below and a little in front of the fibular facet on the lateral condyle and descends to reach the anterior border of the fibular notch, which marks the lateral aspect of the lower end of the tibia. In nearly the whole of its length it affords attachment to the interosseous membrane which connects the tibia to the fibula, As a rule it is poorly defined at its uppermost end, but is easily identified in the rest of its extent. The medial border commences below the anterior end of the groove on the medial condyle and runs downwards to the posterior margin of the medial malleolus. Its upper and lower fourths are rounded and ill-defined, but its middle third is sharper and can be recognized without difficulty.
 The medial surface is bounded in front by the anterior and behind by the medial border. It is broad and smooth, and is subcutaneous throughout its whole extent. The lateral surface, also broad and smooth, is placed between the anterior and the interosseous borders. In its upper three-fourths it is directed laterally and is slightly concave from before backwards. Its lower fourth is carried round on to the front of the bone, owing to the deviation of the anterior border to the medial side and the forward inclination of the lower part of the interosseous border. This part of the surface is somewhat convex forwards. The posterior surface is bounded by the interosseous and the medial borders, and is widest at its upper end, where it is crossed from above downwards and medially by an oblique, roughened ridge, termed the soleal line. The area below this line is subdivided into medial and lateral parts by a faint vertical line, which begins at or just below the middle of the soleal line and soon fades away. A prominent vascular groove marks the bone near the upper end of the vertical line and descends to enter the large nutrient foramen; it may be situated either on the lateral or on the medial side of the vertical line. Particular features.-The anterior border provides attachment for the deep fascia of the leg throughout its whole extent. Just above the medial malleolus it receives the medial end of the superior extensor retinaculum (transverse ligament of the leg). Above the soleal line the medial border gives attachment to subcutaneous the fascia covering the popliteus muscle and to the posterior fibers of the medial (tibial collateral) ligament of the knee-joint; below the soleal line it gives origin for a short distance to fibers of the soleus muscle and attachment to the fascia which covers the deep muscles of the leg. At its lower end it becomes continuous with the medial border of the groove which lodges the tendon of the tibialis posterior muscle. The interosseous border gives attachment to the interosseous membrane of the leg, except at its upper and lower ends. Its upper end is scarcely recognizable, and in this situation there is a large gap in the interosseous membrane for the passage of the anterior tibial vessels. Its lower end forms the anterior boundary of the fibular notch and gives attachment to the anterior inferior tibiofibular ligament.
 The medial surface is usually roughened close to the upper end of the medial border over an area nearly 5 cm. long and 1 cm. wide; this area gives attachment to the longer fibers of the medial (tibial collateral) ligament of the knee-joint. In front of this roughened area the surface provides insertion for the tendons of the sartorius, gracilis and semi tendinosus muscles, which rarely produce markings on the bone. The gracilis, above, and the semitendinosus, below and behind, are inserted immediately in front of the ligamentous area ; the sartorius is inserted into a somewhat curved line, which commences above and descends in front of the two other insertions. The rest of the surface is covered only by superficial fascia and skin, but the lower part is crossed obliquely by the long saphenous vein, as it ascends from in front of the medial malleolus. The lateral surface gives origin in its upper two-thirds, or less, to the tibialis anterior muscle. Its lower part is devoid of muscular attachments, but is crossed by the tendon of the tibialis anterior (which lies along the lateral side of the anterior border), the extensor hallucis longtus, the anterior tibial vessels and nerve (deep peroneal nerve), the extensor digitorum longus and peroneus tertius, in that order from the medial to the lateral side. The posterior surface gives insertion to the popliteus over the triangular area above the soleal line, with the exception of the area adjoining the fibular facet. The soleal line gives attachment to the strong fascia which covers the popliteus muscle, and to the soleus muscle, its covering fascia, and the fascia covering the deep muscles of the leg. The upper end of the line does not reach the interosseous border and is marked by a tubercle, which gives attachment to the medial end of the tendinous arch in the coleus. Lateral to that tubercle the posterior tibial vessels and nerve descend on the surface of the tibialis posterior. Below the soleal line, the vertical line separates the origin of the flexor digitorum longus on the medial side from the origin of the tibialis posterior (fig. 474). The lower fourth, more, of the posterior surface is devoid of muscular attachments, but is intimately related to the tendon of the tibialis posterior as it runs downwards and medially to reach the groove on the back of the medial malleolus. The flexor digitorum longus lies on the posterior surface of the tibialis posterior, crossing it obliquely from the medial to the lateral side, but the posterior tibial vessels and nerve and the flexor hallucis longus come into contact with the lateral part of this surface for a short distance above the lower end of the bone.
 The lower end of the tibia is greatly expanded, and its medial portion projects downwards beyond the rest of the bone to form the medial malleolus. It possesses anterior, medial, posterior, lateral and inferior surfaces. The anterior surface, is smooth and bulges forwards beyond the inferior surface, from which it is separated by a narrow groove. It is continuous above with the lateral surface of the shaft. The medial surface is also smooth and is continuous above with the medial surface of the shaft and below with the medial surface of the medial malleolus. It is subcutaneous and can easily be felt through the skin. The posterior surface is crossed at its medial end by a groove, which is usually conspicuous and can be traced down on to the posterior aspect of the medial malleolus. Elsewhere this aspect of the lower end is smooth and is continuous above with the posterior surface of the shaft. The Lateral surface is formed by a triangular notch, termed the fibular notch, which is intimately related to the lower end of the fibula. The anterior and posterior borders of the notch are salient and converge to meet above on the interosseous crest. The floor of the notch is roughened in its upper part for the attachment of the strong interosseous ligament which binds the lower ends of the two bones securely together. Its lower part is smooth and is sometimes covered with articular cartilage. The inferior surface is smooth for articulation with the body of the talus. Wider in front than behind, it is concave from before backwards and slightly convex from side to side. Medially it is uninterruptedly continuous with the articular surface of the medial malleolus.
 The medial malleolus is a strong pyramidal process, somewhat flattened from side to side. Its medial aspect is smooth and convex, and can easily be felt through the skin. Its lateral aspect is smooth and covered by a comma-shaped articular facet, which articulates with the medial side of the body of the talus. Its anterior aspect is rough, and its posterior aspect bears the lower end of the groove that marks the posterior surface of the lower end of the bone. The lower border of the malleolus is somewhat pointed in front, and behind that, it presents a depression for the attachment of the deltoid ligament of the ankle-joint. Particular features.-The anterior surface of the lower end is related to the tendons, vessels and nerve which lie on the lower part of the lateral surface of the shaft and have already been enumerated. The narrow groove adjoining the anterior border of the inferior surface gives attachment to the anterior and capsular ligaments of the anklejoint. The groove on the posterior surface lodges the tendon of the tibialis posterior, which usually separates the flexor digitorum longus tendon from the bone. More medially the posterior tibial vessels and nerve and the flexor hallucis longus tendon are in contact with this surface. The floor of the fibular notch, especially in its rough upper part, gives attachment to the interosseous tibiofbular ligament; its lower smooth part may be covered with articular cartilage. The anterior and posterior borders of the notch give attachment respectively to the anterior and posterior inferior tibiofibular ligaments. The medial malleolus is shorter than the lateral malleolus and is placed somewhat anterior to it. Its anterior aspect gives attachment to the anterior and capsular ligaments of the ankle-joint. Its posterior aspect is grooved by the tibialis posterior tendon, and the raised medial margin of the groove gives attachment to the flexor retinaculum (laciniate ligament). The upper end of the deltoid ligament is attached to the lower border of the malleolus, both to the pointed anterior part and to the depression behind it.
 Structure.--The structure of the tibia is like that of the other long bones. The compact wall of the shaft is thickest at the junction of the middle with the lower one-third of the bone. Ossification.-The tibia is ossified from three centers (figs. 472, 474, 475) : one for the shaft and one for each end. Ossification begins in the middle of the shaft about the seventh week of feotal life. The center for the upper end appears before or shortly after birth, and from it a thin tongue-shaped process extends downwards in front, to form the tubercle (fig. 475); the center for the lower end appears in the second year. The lower end joins the shaft about the eighteenth year; the upper about the twentieth year. Two additional centers occasionally exist, one for the tongue-shaped process which forms the tubercle, and one for the medial malleolus. |
 Gray's Anatomy 1. Embriology 2. Osteology  Vertebral Column
General Characteristics of a VertebraCervical VertebraThoracic VertebraLumbar VertebraSacral and Coccygeal VertebraVertebral Column as a WholeSternumRibsCostal CartilagesThorax Skull
Introduction Exterior SkullSuperior viewAnterior viewOrbitLateral viewPosterior viewInferior view Interior SkullIntroduction & Skull CapAnterior Cranial FossaMiddle Cranial FossaPosterior Cranial FossaNasal cavityMandibleHyoid Bone Cranial Bones
Occipital BoneSphenoid BoneTemporal BonesParietal BonesFrontal BoneEthmoid BoneInferior Nasal ConchaLacrimal BonesNasal BonesVomerSutural Bones Facial Bones
MaxillaPalatine BoneZygomatic BoneDifferences in Skull due to AgeSex Differences in Skull & Craniology Extremities
Extremities Upper Extremity BonesScapulaClavicleHumerusRadiusUlna HandSkeleton of the HandCarpalsMetacarpalsPhalanges of the HandOssification of bones of the Hand Lower Extremity BonesHip BonePelvisFemurPatellaTibiaFibula FootSkeleton of the FootTarsalsMetatarsalsPhalanges of the FootOssification of bones of the FootComparison of the Bones of the Hand and FootSesamoid Bones 3. Arthrology Trunk Articulations
Mandibular joint (temporomandibular joint) Vertebral Column ArticulationsJoints of the Vertebral BodiesJoints of the Vertebral ArchesSacrococcygeal JointAtlantoaxial Articulation (C1-C2)Vertebral Column with the CraniumCostovertebral ArticulationsSternocostal ArticulationsInterchondral ArticulationsSternal ArticulationsMechanism of the Thorax Upper Extremity Articulations
Sternoclavicular (SC) JointAcromioclavicular (AC) JointLigaments of the ScapulaShoulder Joint (glenohumeral – GH)Elbow JointRadioulnar JointsRadiocarpal Joints (wrist-joint)Intercarpal ArticulationsCarpometacarpal & Intermetacarpal ArticulationsMetacarpophalangeal ArticulationsInterphalangeal Joints Pelvis Articulations
Lower Extremity Articulations
Hip-joint (acetabulofemoral joint - AF)Knee jointTibiofibular JointsAnkle-joint (talocrural)Intertarsal ArticulationsTarsometatarsal & Intermetatarsal ArticulationsMetatarsophalangeal & Interphalangeal ArticulationsArches of the Foot 4. Myology Muscles of the Head
Muscles of the ScalpMuscles of the EyelidMuscles of the NoseMuscles of the MouthMuscles of Mastication Muscles of the Anterolateral Region of the NeckAnterolateral RegionSuperficial & Lateral Cervical MusclesSupra and Infrahyoid MusclesAnterior Vertebral MusclesLateral Vertebral Muscles Muscles of the Trunk
Deep Muscles of the BackSuboccipital MusclesMuscles of the ThoraxMechanism of RespirationMuscles and Fascia of the AbdomenMuscles and Fascia of the PelvisMuscles and Fascia of the PerineumMuscles of the Urogenital Region - MaleMuscles of the Urogenital Region - Female Muscles of the Upper Extremity
Muscles Connecting the Upper Extremity to the Vertebral ColumnMuscles Connecting the Upper Extremity to the Thoracic WallsMuscles and Fascia of the ShoulderMuscles and Fascia of the ArmMuscles and Fascia of the ForearmMuscles and Fascia of the Hand Muscles of the Lower Extremity
Muscles and Fascia of the Iliac Region Muscles and Fascia of the ThighAnterior Femoral MusclesMedial Femoral MusclesMuscles of the Gluteal RegionPosterior Femoral Muscles Muscles and Fascia of the LegAnterior Shin (crural) MusclesPosterior Crural MusclesLateral Crural MusclesFascia Around the AnkleMuscles and Fascia of the Foot 5. Angiology Thoracic Cavity
6. The Arteries Arteries of the Head and Neck
a) Common Carotid ArteryRelationsExternal Carotid Artery Triangles of the Neck Internal Carotid Arteryb) Arteries of the Brain Arteries of the Upper Extremity
Arteries of the Trunk
Descending Aorta Thoracic Aorta Abdominal Aorta Common Iliac Arteries Hypogastric Artery External Iliac Artery Arteries of the Lower Extremity
Femoral Artery Popliteal Fossa Popliteal Artery Anterior Tibial Artery Dorsalis Pedis ArteryPosterior Tibial Artery 7. The Veins Systemic Veins
Veins of the Heart Veins of the Head and NeckVeins of the Exterior of the Head and FaceVeins of the Neck Diploic Veins Veins of the Brain Venous Sinuses of the Dura Mater (Opthalmic and Emissary Veins)Veins of the Upper Extremity and Thorax Veins of the Lower Extremity, Abdomen, and Pelvis 8. The Lymphatic System 9. Neurology Brain or Encephalon
IntroductionHind-brain or RhombencephalonMid-brain or MesencephalonFore-brain or ProsencephalonComposition and Central Connections of the Spinal NervesComposition and Central Connections of the Spinal Nerves 2Pathways from the Brain to the Spinal CordMeninges of the Brain and Medulla Oblongata (Spinalis)Cerebrospinal Fluid Cranial Nerves
Introduction1. Olfactory Nerves2. Optic Nerve3. Oculomotor Nerve4. Trochlear Nerve5. Trigeminal Nerve6. Abducent Nerve7. Facial Nerve8. Acoustic Nerve9. Glossopharyngeal Nerve10. Vagus Nerve11. Accessory Nerve12. Hypoglossal Nerve Spinal Nerves
IntroductionPosterior DivisionsAnterior DivisionsThoracic NervesLumbosacral PlexusSacral and Coccygeal Nerves Sympathetic Nerves
IntroductionCephalic Portion of the Sympathetic SystemCervical Portion of the Sympathetic SystemThoracic Portion of the Sympathetic SystemAbdominal Portion of the Sympathetic SystemPelvic Portion of the Sympathetic SystemGreat Plexuses of the Sympathetic System 10. The Organs of the Senses and the Common Integument The Peripheral Organs of the Special Senses
a. The Organs of Tasteb. The Organ of Smellc. The Organ of Sight 1. The Tunics of the Eye 2. The Refracting Media 3. The Accessory Organs of the Eyed. The Organ of Hearing 1. The External Ear 2. The Middle Ear or Tympanic Cavity 3. The Auditory Ossicles 4. The Internal Ear or Labyrinthe. Peripheral Terminations of Nerves of General Sensations 11. Splanchnology The Respiratory Apparatus
The Respiratory Apparatus a. The Larynx b. The Trachea and Bronchi c. The Pleurae d. The Mediastinum e. The Lungs The Digestive Apparatus
The Digestive Apparatus a. The Mouth b. The Fauces c. The Pharynx d. The Esophagus e. The Abdomen f. The Stomach g. The Small Intestine h. The Large Intestine i. The Liver j. The Pancreas The Urogenital Apparatus
a. Development of the Urinary and Generative OrgansDevelopment of the Urinary and Generative Organs b. The Urinary Organs 1. The Kidneys 2. The Ureters 3. The Urinary Bladder 4. The Male Urethra 5. The Female Urethra c. The Male Genital Organs 1. The Testes and their Coverings 2. The Ductus Deferens 3. The Vesiculae Seminales 4. The Ejaculatory Ducts 5. The Penis 6. The Prostate 7. The Bulbourethral Glands d. The Female Genital OrgansThe Female Genital Organs 1. The Ovaries 2. The Uterine Tube 3. The Uterus 4. The Vagina 5. The External Organs 6. The Mammae The Ductless Glands
a. The Thyroid Glandb. The Parathyroid Glandsc. The Thymusd. The Hypophysis Cerebrie. The Pineal Bodyf. The Chromaphil and Cortical Systemsg. The Spleen 12. Surface Anatomy and Surface Markings Muscle Tables
Muscles of facial expressionMuscles of masticationEye movementPalatePharynxLarynxTongue musclesHyoid MusclesAnterior & Lateral NeckPrevertebralPosterior Neck MusclesSuperficial backDeep backShoulder musclesArm musclesAnterior ForearmPosterior ForearmHand musclesThoracic wallAnterior abdominal wallPosterior abdominal wallPelvic floor musclesGluteal regionPosterior thighAnterior thighMedial thighAnterior & lateral legPosterior legFoot Quizzes 1. Introduction
Anatomical TermsBody RegionsSkeleton IntroductionBones Hand-FootLandmarksJoint ClassificationsActionsMuscle ShapesMuscles Introduction 2. Head & Face
3. Neck
4. Torso
Trunk BonesAnterior TrunkTorso JointsAbdominal Muscles IntroductionBack Muscles IntroductionBack Muscles SuperficialBack Muscles DeepBack Muscles TransversospinalisVertebrae Detailed 5. Shoulder & Arm
6. Forearm, Wrist & Hand
BonesLigamentsAnterior Muscles IntroductionPosterior Muscles IntroductionThenar MusclesCentral Hand MusclesHypothenar Muscles 7. Hip, Thigh & Knee
8. Leg, Ankle & Foot
BonesLigamentsAnterior Leg MusclesLateral Leg MusclesPosterior leg SuperficialPosterior Leg DeepFoot Muscles
|