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Infraspinous fascia
Muscles on the dorsum of the scapula, and the triceps brachii. (Fascia not labeled, but infraspinatous visible near center.)
The infraspinatous fascia is a dense fibrous membrane, covering the infraspinatous muscle and fixed to the circumference of the infraspinatous fossa; it affords attachment, by its deep surface, to some fibers of that muscle. It is intimately attached to the deltoid fascia along the over-lapping border of the deltoideus.