Deep Cervical Fascia: in situObservation
Ming Zhang, MB, MMed, PhD
Department of Anatomy, University of Otago, P.O.Box913, 270 Great King Street, Dunedin 9054, New Zealand, Phone: +64 3 4797378, Fax: +64 3 4797254, email:
BACKGROUND In classical anatomic terms, cervical fascia includes superficial and deep cervical fascia. The deep cervical fascia is further divided into 3 layers: investing, pretracheal and prevertebral fasciae. However, “the cervical fasciae appear in a new form under the pen of each author who attempts to describe them" [1838; Malgaigne]. Such ambiguities are mainly due to the fact that fascia is traditionally viewed “as aggregations of connective tissue that are visible for the unaided eye to detect, allowing it to be dissected gross anatomically” and dissection is the main method of visualizing the fascia. The aim of this project was to systematically investigate the in situ3-dimensional architecture of the deep fascia in neck.
METHODS The necks of 13 cadavers were examined using a combination of sheet plastination and confocal microscopy techniques developed in our laboratory and compared to 9 processed by dissection. The sheet plastination technique preserves and fixes the cellular constituents of tissue in situ by removing lipids and water and replacing them with a curable polymer resin. Thin slices of tissue can then be examined by optical and confocal microscopy.
RESULTS We found that there was no anatomical demarcation between the superficial and deep cervical fasciae. Some layered fascial structures, such as the investing cervical fascia, described in previous studies were created by our dissection procedure and not seen in the plastination studies. We also found that the fascia-like structures examined in our study were closely associated with a muscular structure. For instance, the so-called investing cervical fascia was either the part of the aponeurosis of the platysma or the epimysium of the sternocleidomastoid and trapezius muscles (Figure 1). The nuchal ligament was either the decussated tendinous fibers of the trapezius or the epimysium of the deep posterior cervical muscles (Figure 2). Those muscular-origin fascia-like structures were often merged with the periosteum and dural mater (Figure 3).
CONCLUSIONS At different places, the cervical fascia presented as different types of the muscle-tendon-fascia-periosteum complex. The clinical puzzle that injection of local anaesthetics either in the subcutaneous tissue or under the investing fascia can provide a similarly effective cervical plexus block is explained by our novel finding that there is no so-called investing layer of the deep cervical fascia, thus the injection superficial or deep to the investing cervical fascia is in fact into the same area,The configuration of connective tissue in the cervical region is much more complicated than previously thought. The sub-regional connective tissue architecture warrants further investigation.