Posterior + lateral neck muscles

Question 1

Layer 1: Upper trapezius

Answer 1

Attachments: external occipital protuberance + superior nuchal line –> ligamentum nuchae + lateral 1/3 of clavicle
Actions:
- Unilateral: head + neck extn, head + neck lateral flexion, contra head + neck rotn
- Bilateral: head extn

Question 2

Layer 2: Levator scapulae

Answer 2

Attachments: transverse processes of C1-C4 –> scapula (vertebral border from superior angle to the root of scapula spine)
Actions:
- Unilateral: neck extn, neck lateral flexion, ipsi neck rotn
- Bilateral: neck extn

Question 3

Layer 2: Splenius capitis

Answer 3

Attachments: spinous processes of C7-T4 + lower 1/2 ligamentum nuchae –> mastoid process + superior nuchal line
Actions:
- Unilateral: head + neck extn, head + neck lateral flexion, ipsi head + neck rotn
- Bilateral: head + neck extn

Question 4

Layer 2: Splenius cervicis

Answer 4

Attachments: spinous processes of T3-T6 –> transverse processes of C1-C3
Actions:
- Unilateral: neck extn, neck lateral flexion, ipsi neck rotn
- Bilateral: neck extn

Question 5

Layer 2: ES in the neck

Answer 5

Attachments: mastoid process (longissimus), transverse processes of C2-T6, articular processes of C4-C7, ~ angles of ribs 1-6 (iliocostalis)
Actions:
- Unilateral: head lateral flexion (longissimus), neck lateral flexion (iliocost./long.), ipsi head rotn (longissimus), ipsi neck rotn (iliocost./long.)
- Bilateral: head extn (longissimus), neck extn (all 3)

Question 6

Layer 3: Semispinalis capitis

Answer 6

Attachments: transverse processes of T1-T6, articular processes of C4-C7 –> occipital bone b/w superior + inferior nuchal lines
Actions:
- Unilateral: head + neck lateral flexion, contra head + neck rotn (most lateral fibres)
- Bilateral: head + neck extn

Question 7

Layer 4: Semispinalis cervicis

Answer 7

Attachments: transverse processes of T1-T6 –> spinous processes of C2-C6
Actions:
- Unilateral: neck (mid-cervical) extn, head + neck lateral flexion, contra neck rotn
- Bilateral: neck (mid-cervical) extn

Question 8

Layer 4: Suboccipitals - Rectus capitis posterior major / minor

Answer 8

Attachments: spinous process of axis –> inferior nuchal line (RCPMaj.), posterior tubercle of atlas –> inferior nuchal line (RCPMin.)
Actions:
- Unilateral: head extn, head lateral flexion, ipsi head rotn
- Bilateral: head extn

Question 9

Layer 4: Suboccipital group - Inferior + superior obliques

Answer 9

Attachments: spinous process of axis –> transverse process of atlas (IO), transverse process of atlas –> b/w superior + inferior nuchal line (SO)
Actions:
- Unilateral: head extn (SO), extn of atlas (IO), head lateral flexion (SO), ipsi head rotn (IO), contra head rotn (medial fibres of SO)

Question 10

Layers 5 + 6: Multifidus + rotatores

Answer 10

Attachments: transverse or articular processes of upper thoracic or lower cervical vertebra –> cervical spinous processes of 1-4 or 5 segments above (MF), transverse of a cervical vertebra –> lamina of vertebra above (rotatores)
Actions:
- Unilateral: neck extn (MF), neck lateral flexion (MF), contra neck rotn
- Bilateral: neck extn

Question 11

Ligamentum nuchae (Nuchal ligament)

Answer 11

• a large thick structure in the midline of the posterior neck comprising a:
  1. thick, flat raphe: extending from the non-bifid spinous process of C7 to the inion, continuous with the supraspinous ligament
  2. thin septum (wall): composed of fascia connecting the raphe to the bifid spinous processes (C2-C6) + the posterior tubercle of the atlas (C1)
  Functions:
• the raphe = formed by the aponeuroses of 4 neck muscles meeting in the midline (upper traps, splenius cap, rhomboid minor, serratus posterior superior) = ‘attach’ to ligamentum nuchae
• the septum: seperates the left + right side neck muscles, maintains an indirect contact b/w the superficial neck muscles + underlying spinous processes (sps)