How To Study Bone

Hello future Dr.

I am Pawan nagar from TCML Team. In this article we will try to understand, How can we easily understand the bones (Side determination, external features, and attachment) and remember them for a long time.

Here we are giving a superficial idea to study bone and if you want to study each bone in detail visit our youtube channel The Charsi of Medical Literature / TCML and make bone chart from TCML videos.

If you want to bones notes/charts (each bone one chart explanation) download TCML mobile app (Available on the play store and it is free for all users)

OVERVIEW:

Here we covered each bone into below three points-

1. Side determination: Right and Left Side.
2. External features: Tubercle, Tuberosity, Sulcus, Border, Surface, Process, Fossa etc.
3. Attachment: Muscles, Ligaments, Aponeurosis etc.

1. Side determination:

Bone side determination is a very confusing point for students.

Many students are confused in this as to why it is the right side bone and why it is the left side bone.

And At this point, we will try to give answers to all confusion regarding the side determination of the bone.

At first, take the bone in your hand and find the below structure into the bone that is given below in three points.

A. Upper and lower end: If we identify which structure are present on upper and lower end of the bone, we can easily understand and differentiate right and left side of bone.

(Only for long Bones Humerus, Radius, Ulna, Femur, Tibia, and Fibula bone)

eg 1. Greater and lesser tubercles (Not Trochanter) are present on the upper end of the humerus bone. (See Figure- 1)

eg 2. The upper end of the radius bone is disc-shaped or round. (See Figure- 3)

eg 3. C- shape trochlear notch is present on the upper end of the ulna bone. (See Figure- 2)

Concavity of trochlear notch are present on the anterior side.

eg 4. Greater and Lesser trochanter (Not Tubercle) are present on the upper end of the femur bone.

g 5. Tibial tuberosity are present on anterior side of upper end of tibia bone.

eg 6. The malleolar fossa is present on the medial surface of the lower end of the fibula bone.

B. Lateral and Medial side: (Same as upper and lower end)

If we identify which structure are present on lateral and medial side of the bone, we can easily understand and differentiate right and left side of bone.

● The rounded head of the humerus bone (form shoulder joint) is present on medial side.

● Radius bone: below we are talking about the medial and lateral sides of the radius bone

The medial border of the radius bone (Interosseous border) are sharp.

Radial tuberosity of radius bone present on the medial side

Styloid processes of the radius bone are present on the lateral side of the lower end of the radius bone.

● Ulna bone:
The lateral border of the ulna bone (The interosseous border) are sharp.

C- shape trochlear notch is present on the upper end of the ulna bone. (Concavity of trochlear notch are present on the anterior side)

● The rounded head of the femur bone (form Hip joint) is present on medial side.

● for tibia bone:
A fibular notch is present on the lateral side of the upper end of the tibia bone.

On the medial side of the lower end of the tibia bone, medial malleolus is present.

● The malleolar fossa is present on the medial surface of the lower end of the fibula bone.

C. Anterior and Posterior side: (Same as upper and lower end)

If we identify which structure are present on anterior and posterior side of the bone, we can easily understand and differentiate right and left side of bone.

● for humerus bone

Coronoid fossa (for the coronoid process of ulna bone) and Radial fossa (for the rounded head of radius bone) are present on the anterior side of the lower end of humorous bone.

Olecranon fossa (for the olecranon process of ulna bone) are present on the posterior side of the lower end of humorous bone.

● for femur bone

The intertrochanteric crest is present on the posterior side of the upper end of the femur bone.

Intertrochanteric lines are present on the anterior side of the upper end of the femur bone.

Intercondylar fossa is present on the posterior side of the lower end of the femur bone.

● The tibial tuberosity is present on the anterior side of the upper end of the Tibia bone.

● The malleolar fossa is present on the posteroinferior side of the medial surface of the lower end of the fibula bone.

After Overall discussion

Humerus Side determination:
1. Upper and Lower end:
Greater and lesser tubercles (Not Trochanter) are present on the upper end of the humerus bone.

2. Lateral and Medial side:
The rounded head of the humerus bone (form Shoulder joint) is present on medial side.

3. Anterior and Posterior side:
Coronoid fossa (for the coronoid process of ulna bone) and Radial fossa (for the rounded head of radius bone) are present on the anterior side of the lower end of humerus bone.

Olecranon fossa (for the olecranon process of ulna bone) are present on the posterior side of the lower end of the humerus bone.

Radius bone side determination: Explained above in point 1 (side determination)
Upper and lower end-
Lateral and medial side
The anterior and posterior side

Ulna bone side determination: Explained above in point 1 (side determination)
Upper and lower end
Lateral and medial side
The anterior and posterior side

Femur bone side determination: Explain in point 1 (side determination)
Upper and lower end
Lateral and medial side
The anterior and posterior side

Tibia bone side determination: Explained above in point 1 (side determination)
Upper and lower end
Lateral and medial side
The anterior and posterior side

Fibula bone side determination: Explained above in point 1 (side determination)
Upper and lower end
Lateral and medial side
The anterior and posterior side

2. External Features:

External features means what structure we see in bones from outside. For example- Tubercle, Tuberosity, Border, Surface, Sulcus, Groove, Fossa, Notch, Condyle, and Process etc.

After studying bone external features we can easily understand the attachment (Point 3) of the bones.

We study bone external features into below three parts- Upper end, Shaft, and Lower end

To understand this point (Point 2), we have given some examples below. (Here only upper end external features are given)

● Humerus Bone: Humerus upper end have following external features: Head, Neck, Greater tubercle, Lesser tubercle, Bicipital Groove or Intertubercular line.

● Radius Bone: Radius upper end have following external features: Head, Neck, and Radial tuberosity.

● Ulna Bone: Ulna upper end have following external features: Coronoid process, Olecranon process, Trochlear notch, and radial notch.

Femur Bone: Femur upper end have following external features: Head, Neck, Greater trochanter, Lesser trochanter, intertrochanteric line, and intertrochanteric crest.

● Tibia Bone: Tibia upper end have following external Features: Medial condyle, Lateral condyle, intercondylar area, and tibial tuberosity.

● Fibula Bone: upper end have following external Features: Head, Styloid process, and Neck.

3. Attachment:

After studying external features (Point 2) we can easily understand attachment of bones, because muscles and ligaments are attach on it.

We have given some examples below.

● Humerus Bone:
On Greater Tubercle- Three muscles are attached (Supra Spinatous muscle, Infra spinatous muscle, Teres minor muscle)

On Lesser Tubercle- One muscle are attached (Subscapularis muscle)

● Radius Bone: On Radial tuberosity: Biceps brachii muscle are attached.

● Ulna Bone:
On Olecranon process: Triceps brachii muscle are attached.
On Coronoid process: Annular ligament, Brachialis muscle, Supinator muscle are attached.

Femur Bone:
On greater trochanter: Piriformis, Gluteus minimus, Gluteus medius, Obturator externus, Obturator internus, Superior gemellus, Inferior gemellus muscle are attached.

On lesser trochanter: Posas major, and iliacus muscle are attached.

● Tibia Bone:
On Tibia tuberosity: Ligamentum patellae are attached
On Lateral condyle: ilio tibial tract are attached

● Fibula Bone:
On head: Biceps femoris muscle are attached