4.2 Bones of the Head, Face, Neck, Arms, Hands, Legs and Feet

Bones of the Head, Face, Neck and Limbs

Exam Focus: The exam asks for identification, not clinical depth. Memorise the 8 cranial and 14 facial bone counts, the occipital and parietal bones as haircutting reference points, the mandible as the only movable skull bone, and the hand and foot counts of 27 and 26. Ulna equals little finger, radius equals thumb is the reliable mnemonic.

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1. Osteology: Skeletal Framework of the Head, Face, and Neck

Osteology is the scientific study of the anatomy, structure, and diseases of bones. An adult human skeleton comprises 206 bones, which provide structural support, protect vital organs, act as mechanical levers for muscle attachments, store calcium and minerals, and produce blood cells within the bone marrow.

                     SKELETON OF THE HEAD (SKULL)
                   ┌──────────────┴──────────────┐
                   ▼                             ▼
            CRANIUM (8 Bones)             FACE (14 Bones)
       ┌───────────┴───────────┐      ┌──────────┴──────────┐
       │ 1 Occipital           │      │ 2 Nasal             │
       │ 2 Parietal            │      │ 2 Lacrimal          │
       │ 1 Frontal             │      │ 2 Zygomatic (Malar) │
       │ 2 Temporal            │      │ 2 Maxillae          │
       │ 1 Ethmoid             │      │ 1 Mandible          │
       │ 1 Sphenoid            │      │ 2 Turbinal          │
       └───────────────────────┘      │ 1 Vomer             │
                                      │ 2 Palatine          │
                                      └─────────────────────┘

The 8 Cranial Bones (Enclosing & Protecting the Brain)

1. Occipital Bone (1): Forms the back and base of the cranium. Contains the foramen magnum through which the spinal cord connects to the brainstem. The external occipital protuberance is a prominent bony landmark used when sectioning hair for haircuts and determining the occipital reference point.
2. Parietal Bones (2): Form the crown (vertex), upper sides, and roof of the cranium. They join together at the sagittal suture and meet the frontal bone at the coronal suture.
3. Frontal Bone (1): Forms the forehead, the superior margins of the eye orbits, and the anterior cranial floor.
4. Temporal Bones (2): Form the lower sides of the head in the ear region, housing the internal ear structures and acoustic meatus. Each temporal bone features the zygomatic process and the mastoid process located just behind the earlobe.
5. Ethmoid Bone (1): A light, delicate, spongy bone positioned between the two eye sockets; forms part of the anterior cranial base, the medial orbital walls, and the superior nasal septum.
6. Sphenoid Bone (1): A complex, bat-shaped or butterfly-shaped bone that spans the floor of the cranium, joining and locking all other cranial bones together.

The 14 Facial Bones (Providing Facial Framework)

1. Nasal Bones (2): Small, oblong bones placed side-by-side that form the bridge of the nose.
2. Lacrimal Bones (2): The smallest and most fragile bones of the face; situated at the anterior medial wall of each eye orbit (near the tear ducts).
3. Zygomatic Bones / Malar Bones (2): Form the prominence of the cheeks (cheekbones) and the lateral orbital floor; crucial reference points for contouring makeup application.
4. Maxillae (2): The two upper jawbones fused at the midline; form the upper jaw, the roof of the mouth (hard palate), the anterior floor of the eye orbits, and sides of the nasal cavity. House the upper dental arch.
5. Mandible (1): The lower jawbone; the largest, strongest, and only movable bone of the entire facial skeleton. Houses the lower dental arch and articulates with the temporal bones at the temporomandibular joint (TMJ).
6. Turbinal Bones / Inferior Nasal Conchae (2): Thin, curved, spongy bone layers projecting along the outer lateral walls of the nasal cavity.
7. Vomer (1): A single, flat, thin trapezoidal bone forming the posterior and inferior portion of the nasal septum.
8. Palatine Bones (2): L-shaped bones located at the back of the nasal cavity; form the posterior hard palate of the oral cavity and the floor of the nasal cavity.

Bones of the Neck, Chest, and Shoulder Girdle

• Hyoid Bone (1): A unique U-shaped bone situated at the base of the tongue in the anterior neck; it does not articulate directly with any other bone and supports tongue muscles and swallowing.
• Cervical Vertebrae (7): The 7 topmost vertebrae of the vertebral column forming the flexible skeletal structure of the neck ($C_1$ to $C_7$). $C_1$ is the Atlas (supports the skull) and $C_2$ is the Axis (allows head rotation).
• Clavicle (Collarbone): Slender S-shaped bone extending horizontally across the anterior shoulder girdle connecting the sternum to the scapula.
• Scapula (Shoulder Blade): Large, flat, triangular bone positioned on the posterior thoracic wall (one on each side of the upper back).
• Thorax / Chest Framework: Consists of the Sternum (breastbone), 12 pairs of Ribs, and 12 Thoracic Vertebrae, protecting the heart and lungs.

2. Bones of the Arm and Hand

Manicuring includes hand and arm massage, and 19 NYCRR § 162.4 lists "Manipulations of the Hand, Arm, Leg and Foot" as a nail care topic. Massage that follows skeletal and muscular structure is both safer and more effective.

Total: 27 bones in each hand. The mnemonic that survives exam pressure is 8 + 5 + 14 = 27.

3. Bones of the Leg and Foot

Pedicuring includes lower leg and foot massage, and the diabetic-client precautions in Chapter 12 depend on knowing this structure.

Total: 26 bones in each foot — 7 + 5 + 14 = 26. Note the pattern: the hand has one extra bone because it has eight carpals to the foot's seven tarsals.

4. Why This Matters in Service

• Haircutting reference points. The parietal ridge, occipital bone and apex are named after the underlying skull anatomy, and Chapter 8 uses them to locate every guideline. The occipital bone is found by resting a comb flat against the nape: the point where the comb leaves the head is the occipital.
• Facial massage and contouring. The zygomatic (malar) bones define the cheekbones that Chapter 13's contouring section highlights, and the mandible defines the jawline.
• Pressure and comfort. Massage over the calcaneus, patella or the bony prominence of the tibia should be light; effective massage pressure belongs over muscle, not directly over bone.
• Client safety. A client with a healing fracture, recent surgery, or joint replacement in a limb is not a candidate for vigorous hand, arm, leg or foot manipulation. As always, diagnosis is outside the licence: the correct action is to modify or decline the massage element and continue the cosmetic service.