Human Anatomy & Physiology for Cosmetologists

Human Anatomy & Physiology for Cosmetologists

Cosmetology is rooted in the biological sciences. Every service performed in the salon—from a simple scalp massage or haircut to an intricate facial or pedicure—directly interacts with the anatomical structures of the human body. A thorough understanding of anatomy, physiology, and histology protects clients from physical injury, prevents muscle strain for the practitioner, and ensures professional, state-compliant results.

• Anatomy: The scientific study of the structures of the human body and the physical relationships among its parts.
• Physiology: The study of the functions and vital activities performed by those body structures.
• Histology (Microscopic Anatomy): The study of tiny structures found in living tissues, including skin, hair, and nails.

---

Osteology: The Skeletal Framework

Osteology is the scientific study of the anatomy, structure, and functions of bones. The adult human skeleton contains 206 bones that provide structural support, protect internal organs, serve as attachment sites for muscles, store essential minerals (such as calcium and phosphorus), and produce red and white blood cells within the bone marrow. For the Cosmetology State Board Exam, candidates must master the bones of the cranium, face, neck, shoulders, arms, hands, legs, and feet.

Bones of the Cranium

The skull is divided into the cranium (an oval, bony case that protects the brain) and the facial skeleton. The cranium consists of 8 bones:

1. Occipital Bone: Forms the back and base of the skull above the nape of the neck.
2. Parietal Bones (2): Form the sides and crown (top) of the cranium.
3. Frontal Bone: Forms the forehead.
4. Temporal Bones (2): Form the sides of the head in the ear region.
5. Ethmoid Bone: Light, spongy bone between the eye sockets that forms part of the nasal cavities.
6. Sphenoid Bone: Joins all of the bones of the cranium together, located behind the eye sockets.

Bones of the Face

The facial skeleton comprises 14 bones, but cosmetologists focus primarily on those involved in facial manipulations and makeup application:

• Nasal Bones (2): Form the bridge of the nose.
• Lacrimal Bones (2): Small, fragile bones located at the front inner wall of the eye sockets.
• Zygomatic Bones (2) (Malar bones): Form the prominence of the cheeks (cheekbones).
• Maxillae (2): Upper jawbones that assist in forming the orbit and roof of the mouth.
• Mandible: The lower jawbone; the largest and strongest bone of the face, forming the only movable joint in the skull.
• Turbinal Bones (2), Vomer, and Palatine Bones (2): Internal facial structures forming nasal passages and the hard palate.

Bones of the Neck, Chest, and Shoulders

• Hyoid Bone: U-shaped bone at the base of the tongue that supports tongue muscles.
• Cervical Vertebrae: The 7 bones of the top portion of the vertebral column located in the neck.
• Sternum (Breastbone): Flat bone forming the anterior ventral support of the ribs.
• Ribs: 12 pairs of bones forming the protective wall of the thorax.
• Clavicle (Collarbone): Connects the sternum to the scapula.
• Scapula (Shoulder Blade): Large, flat triangular bone of the shoulder.

Bones of the Arms and Hands

Manicuring services require exact knowledge of the upper extremities:

• Humerus: The upper and largest bone of the arm, extending from the elbow to the shoulder.
• Radius: The smaller bone on the thumb side of the forearm.
• Ulna: The larger bone on the little-finger side of the forearm, forming the point of the elbow.
• Carpus (Wrist): Flexible joint composed of 8 small, irregular bones held together by ligaments.
• Metacarpus (Palm): Consists of 5 long bones extending between the wrist and fingers.
• Phalanges (Digits): The bones of the fingers and thumb. Each hand contains 14 phalanges (3 per finger, 2 in the thumb).

Bones of the Legs and Feet

Pedicuring services involve the lower extremities:

• Femur: Heavy, long bone forming the thigh.
• Patella (Kneecap): Accessory bone forming the knee joint.
• Tibia: Larger of the two lower leg bones on the big-toe side; carries body weight.
• Fibula: Smaller lower leg bone on the little-toe side.
• Tarsus: Ankle region composed of 7 tarsal bones, including the talus (ankle bone) and calcaneus (heel bone).
• Metatarsus: Instep of the foot consisting of 5 long bones.
• Phalanges: The 14 bones of the toes (2 in the great toe, 3 in each remaining toe).

---

Myology: The Muscular System

Myology is the study of the structure, function, and diseases of muscles. Muscles make up over 40% of body weight and generate movement when stimulated. There are over 630 muscles in the human body, classified into three primary structural types:

1. Striated Muscles (Skeletal/Voluntary): Controlled by conscious will. Attached to bones and responsible for movement during facial treatments, manicures, and walking.
2. Non-Striated Muscles (Smooth/Involuntary): Function automatically without conscious thought. Located in internal organs such as the stomach, intestines, and blood vessels.
3. Cardiac Muscle: Involuntary, striated muscle found exclusively in the heart.

Parts of a Skeletal Muscle

Every skeletal muscle features three structural divisions:

• Origin: The fixed, immovable attachment of the muscle to a bone or non-movable structure.
• Belly: The middle, fleshy region of the muscle between the origin and insertion.
• Insertion: The movable attachment point of the muscle to a bone, skin, or another muscle.

CRITICAL MASSAGE RULE: Massage movements, electrical stimulation, and physical pressure must ALWAYS be directed from the INSERTION TO THE ORIGIN of the muscle. Massaging in reverse (origin to insertion) pulls against natural muscle attachment, causing tissue sagging and muscle damage.

Key Head, Scalp, and Facial Muscles

• Epicranius (Occipitofrontalis): Broad muscle covering the top of the skull, consisting of two parts:
  • Frontalis: Anterior portion that raises eyebrows, draws scalp forward, and causes horizontal forehead wrinkles.
  • Occipitalis: Posterior portion that draws the scalp backward.
• Epicranial Aponeurosis: Tendon connecting the frontalis and occipitalis.
• Orbicularis Oculi: Ring muscle around the eye socket; enables eye closure and winking.
• Corrugator Supercilii: Located beneath the frontalis; draws eyebrows down and inward, producing vertical forehead frown lines.
• Procerus: Covers the bridge of the nose; depresses eyebrows and causes transverse wrinkles across the nose bridge.
• Orbicularis Oris: Flat band around the upper and lower lips; compresses, contracts, puckers, and folds the lips.
• Zygomaticus Major and Minor: Muscles extending from zygomatic bone to mouth corners; elevate the lip for smiling.
• Masseter & Temporalis: Mastication (chewing) muscles that open and close the mandible.
• Platysma: Broad muscle extending from chest/shoulder to side of chin; depresses lower jaw and lip.
• Sternocleidomastoideus (SCM): Muscle of the neck extending from clavicle to temporal bone; rotates and depresses the head.

Arm and Hand Muscles

• Biceps: Front of upper arm; flexes elbow and supinates forearm.
• Triceps: Back of upper arm; extends forearm.
• Pronator: Turns hand inward so palm faces downward.
• Supinator: Turns hand outward so palm faces upward.
• Flexors: Wrist muscles that bend the wrist and draw fingers into a fist.
• Extensors: Wrist muscles that straighten the wrist, hand, and fingers.
• Abductors: Separate the fingers outward away from the middle finger.
• Adductors: Draw the fingers inward toward the middle finger.

---

Circulatory & Nervous System Highlights

• Nervous System: Controls and coordinates body activities. Cosmetologists interact with the Fifth Cranial Nerve (Trigeminal / Trifacial—chief sensory nerve of the face) and the Seventh Cranial Nerve (Facial nerve—chief motor nerve of the face).
• Circulatory System: Controls blood circulation. The common carotid arteries supply blood to the head, face, and neck, while the internal and external jugular veins return blood from the head back to the heart.

---

Anatomical Comparison Table