4Notes Scapula

Introduction to the Scapula

  • Also known as the shoulder blade.

  • Flat and irregularly shaped, resembling a shovel.

Primary Bony Landmarks of the Scapula

Borders

  • Medial Border (Vertebral Border)

    • Closest to the vertical column.

  • Lateral Border (Axillary Border)

    • Located on the lateral side and near the armpit.

Fossae

  • Subscapular Fossa

    • Located on the deep surface against the ribs, also called the costal surface.

    • Home to the subscapularis muscle, which arises from this fossa.

  • Supraspinous Fossa

    • Situated above the spine of the scapula.

    • Contains the supraspinatus muscle.

  • Infraspinous Fossa

    • Located below the spine of the scapula.

    • Houses the infraspinatus muscle.

Special Structures

  • Acromion

    • The highest point of the shoulder, derived from Greek words "akron" (highest) and "omus" (shoulder).

    • Articulates with the clavicle to form the acromioclavicular joint (AC joint), a synovial plane joint crucial for shoulder movement.

  • Spine of the Scapula

    • A spiny ridge along the back, where muscles like the trapezius and deltoid attach to support scapula movement.

Glenoid Cavity

  • Glenoid Cavity (Glenoid Fossa)

    • A shallow socket on the lateral surface that articulates with the head of the humerus, forming a ball-and-socket joint.

  • Supraglenoid Tubercle

    • Bony prominence above the glenoid cavity for muscle attachment, specifically for the long head of the biceps brachii.

  • Infraglenoid Tubercle

    • Located below the glenoid cavity, serves as the attachment for the long head of the triceps brachii.

Coracoid Process

  • Recognized for its crow's beak shape (Greek: coracoid).

  • Important for muscle attachment (pec minor, short head of biceps, coracobrachialis).

  • Located below the lateral third of the clavicle, acts as a palpable landmark.

Suprascapular Notch

  • Notch on the top of the scapula, associated with the suprascapular ligament.

  • Contains the suprascapular artery (above the ligament) and suprascapular nerve (through the foramen).

Importance of Learning about the Scapula

  • Understanding scapular anatomy is crucial for:

    • Identifying muscle attachments and movements.

    • Recognizing the relationship between the scapula and arm movement.

    • Providing insights into shoulder injuries and conditions.