Chapter 37: Neck Spaces and Fascial Planes

Introduction

The advent of advanced imaging and powerful antimicrobial therapy has allowed more deep neck space infections to be managed with medical therapy alone. However, detailed knowledge of the neck spaces and fascial planes is mandatory in order to predict patterns of spread and the possible effects on surrounding structures. In addition, detailed knowledge is required should surgical intervention prove necessary. The goal of surgery for deep neck space infections is to stop the progression of disease while preserving normal vital structures. With the rise of resistant organisms such as methicillin-resistant Staphylococcus aureus (MRSA), surgery will continue to remain a critical component in the management of deep neck space infections.

Anatomy

Triangles of the Neck

Anterior Cervical Triangle

1. Boundaries (Figure 37-1)

   1. Superior: mandible

   2. Anterior: midline

   3. Posterior: sternocleidomastoid

2. Subordinate triangles

   1. Submaxillary (digastric) triangle

      1. Superior: mandible

      2. Anterior: anterior belly of digastric

      3. Posterior: posterior belly of digastric

   2. Carotid triangle

      1. Superior: posterior belly of digastric

      2. Anterior: superior belly of omohyoid

      3. Posterior: sternocleidomastoid

   3. Muscular triangle

      1. Superior: superior belly of omohyoid

      2. Anterior: midline

      3. Posterior: sternocleidomastoid

   4. Submental (suprahyoid) triangle

      1. Superior: symphysis of mandible

      2. Inferior: hyoid bone

      3. Lateral: anterior belly of digastric

Posterior Cervical Triangle

1. Boundaries

   1. Anterior: sternocleidomastoid

   2. Posterior: trapezius

   3. Inferior: clavicle

2. Subordinate triangles

   1. Occipital triangle

      1. Anterior: sternocleidomastoid

      2. Posterior: trapezius

      3. Inferior: omohyoid

   2. Subclavian triangle

      1. Superior: omohyoid

      2. Inferior: clavicle

      3. Anterior: sternocleidomastoid

Fascial Planes of the Neck

Superficial Cervical Fascia

1. Envelopes (Figure 37-2)

   1. Platysma

   2. Muscles of facial expression

2. Boundaries

   1. Superior: zygomatic process

   2. Inferior: clavicle

3. Significance

   1. Main plane of resistance to deep neck spread of cellulitis

   2. Allows mobility of skin over deep neck structures

   3. Easily separated when raising neck flaps from deep cervical fascia in the subplatysmal potential space (adipose, sensory nerves, blood vessels)

Deep Cervical Fascia

1. Superficial layer (investing fascia)

   1. Envelopes

      1. Trapezius, sternocleidomastoid, strap muscles

      2. Submandibular and parotid glands

      3. Muscles of mastication: masseter, pterygoids, temporalis

   2. Boundaries

      1. Superior: mandible and zygoma

      2. Inferior: clavicle, acromion, spine of scapula

      3. Anterior: hyoid bone

      4. Posterior: mastoid process, superior nuchal line of cervical vertebrae

   3. Significance

      1. Outlines masticator space superiorly

      2. Forms stylomandibular ligament posteriorly (separates parapharyngeal and submandibular spaces)

      3. Splits ...