Suprapleural membrane and suprapleural bands

Abstract

The pleural cupola is covered by a distinct dome-shaped suprapleural membrane (Sibson's fascia) formed by a condensation of endothoracic fascia and continuous at its periphery with the more diffuse, loose endothoracic connective tissue lying between the ribs and the parietal pleura. This does not agree with the classic description of Sibson's fascia. It forms a discreet cervicothoracic cloison which can be readily separated from the pleura and adjacent mediastinal structures. Attaching to the membrane are the vertebromembranous, transversomembranous, and costomembranous bands which are formed by prevertebral fascia. In addition, the last two suprapleural bands receive contributions from the fibrous remains of the scalenus minimus muscle. The muscle was found to be present on one or both sides in 30 out of 64 bodies (46.8% ). The suprapleural membrane and bands can become hypertrophied and fibrous as a result of pathology in this cupola area of the lung. The bands have been implicated in certain clinical syndromes.

Nerves of the Upper Extremity

“…A scalenus minimus muscle (of Albinus, scalenus pleuralis, petit scalene, scalenus accessorius, scalenus anticus minor, Sibson's muscle), which originates on the seventh cervical transverse process and inserts on the inner margin of the first thoracic rib, passes anterior to the brachial plexus and posterior to the subclavian artery. This muscle may be present in 4-100% of specimens: 4% (Natsis et al 2013), 10% (Cordier and Devos 1938), 25% (Hafferl 1939), 30% (Daseler and Anson 1959), 33% (Boyd 1934), 34% (Telford and Mottershead 1948), 43% (Macalister 1864), 47% (Gaughran 1964), 54% (Stott 1928), 61% (Gage and Parnell 1947), 72% (Zuckerkandl 1894), or 100% (Le Double 1897). Accessory scalene muscles may also be interpreted as a scalenus minimus, which may artificially inflate the incidence (Paraskevas et al 2007).…”

“…91.3). There is much disagreement on the precise composition of these fascial attachments between the pleural apex and structures at the root of the neck, as summarized by Gaughran (1964) ( Fig. 91.4).…”

“…Common variations include passage of the fifth cervical nerve superficial to the anterior scalene (2% of specimens, Matejcik 2005; 3%, Natsis et al 2006;3%, Harry et al 1997) Source: Poirier and Charpy (1901). Source: Gaughran (1964). Reproduced with permission from John Wiley & Sons. or piercing the muscle (1% of specimens, Natsis et al 2006;13% Harry et al 1997), the upper trunk superficial to the anterior scalene (2% of specimens, Natsis et al 2006) or perforating the muscle (6% of specimens, Natsis et al 2006;15%, Harry et al 1997), and the fifth cervical and sixth cervical nerves independently perforating the muscle (6% of specimens, Harry et al 1997).…”