THE HUMAN SKELETON

INTRODUCTION ;
                 
 Bony and cartilaginous framework of the  body consititutes the skeleton.

                                                                                                                Anterior view
HOMOLOGOUS PART OF THE LIMB

Upper Limb it include
1.Shoulder girdle
2.Shoulder Joint
3.Arm With Humerus
4.Elbow Joint
5.Forearm Radius and Ulna
6.Wrist Joint
7.Hand With
 (a) Carpus
 (b) Metacarpus
 (c) 5 Digits

                                                                                  Posterior View

Lower Limb
1.Hip Girdle
2.Hip Joint
3.Thigh With Femer
4.Knee Joint
5.Leg With Tibia and Fibula
6.Ankle Joint
7.Foot With
 (a) Tarsus
 (b) Metatarsus
 (c) 5 Digits



The Skeleton divided in to two :


 ENDOSKELETON : - It is located internally in body.in human anatomy the term skeleton usually means endoskeleton


 EXOSKELETON    : - In human beings the exoskeleton is very rudimentary being  represented by nails & enamel of teeth only.



NUMBER OF BONES : 206

Upper Limb-----------------64
Lower Limb-----------------62
Vertebrae--------------------33
Skull--------------------------29
(Facial Bones - 14, Cranial - 14, hyoid bone - 1)
Ribs---------------------------24
Sternum------------------------1

CLASSIFICATION OF BONES : BASED ON

A.ACCORDING TO POSITION

(1) Axial        : Bones Forming the axis of the body.

                         Eg. Skull, Ribs, Sturnum, Vertirae

 (2) Appendicular : Bones forming the skeleton of the limbs

B. ACCORDING TO SHAPE AND SIZE

(1) Long bone          : present in upper limb and lower limb

(2) Short long bone : They are miniature in size,

                                   eg. Metacarpal & Metarsal and Phalanges

(3) Short bone         : they are small and cuboidal in shape.

                                    eg. Carpal & Tarsal bone.

(4) Flat bone           : They are expanded & protect the vital struct.
                                   eg. Scapula,Sternum, Ribs, Pareital  & Frontal bones.                       

(5) Irregular Bone  : Irregular in out line.

                                   eg. this include Vertebrae,  some skull bones.

(6) Pnumatic bone  : Flat or irregular bone possessing a hollow space within there body which                                              contains air, eg. Ethmoide, Maxilla, Mastoid part of temporal bone.

(7) Sesamoid Bone   : it means seed like, eg: Patella, Pisiform Bone,

(8) Warmian Bones  : Sutural bones. These are found along the sutures,

                                     Can be mistaken for fractures.

C. ACCORDING TO GROSS STRUCTURE :-

(1) Compact (lamellar) bone   - Outer cortical part of long bone which is hard.

(2) Spongy (cancellous) bone - The part of bone which is less hard.

(3) Diploic bone  - Consist of inner & outer tables of compact bone.with an intervening porous layer which is occupied by a spongy substance consisting of bone marrow and diploic veins.

D. ACCORDING TO DEVELOPMENT : -

(1) Membranous (Ectochondral) bones - Which develop in membrane.

(2) Cartilaginous (Endocondral) bones - Which develop in cartilage