Morphometry, histochemistry, and innervation of cervical shoulder muscles in the cat

Abstract

Morphometric and histochemical methods were used to estimate the force‐developing capabilities and fiber‐type contents of four muscle complexes (rhomboideus, levator scapulae, trapezius, and sternomastoideus) that link the shoulder girdle to the skull and cervical vertebrae. Each complex contained at least two member muscles that were distinctive architecturally and often had specialized innervation patterns. Trapezius and sternocleidomastoideus were innervated by both cranial nerve XI and cervical spinal nerves. Glycogen depletion of trapezius suggested that the nerves derived from cervical roots might be entirely sensory. Muscles within each complex varied in physiological cross‐sectional area from less than 0.1 cm2 to greater than 1 cm2. They showed differences in fiber‐type composition that suggested specialized roles for different behaviors. The morphometric features of the cervical shoulder muscles suggest that they have considerable potential to produce head movements and should be incorporated into feline head‐movement models. J. Morphol. 239:255–269, 1999. © 1999 Wiley‐Liss, Inc.

Origin of the Roots of the Accessory Nerve in the Goitred Gazelle and Tuj Sheep

“…The results of this study on the course, branches and distribution of the accessory nerves in the goitred gazelle and Tuj sheep were similar to those of other species in reports that mentioned the presence of both the cranial and spinal origins of the accessory nerve (Miller, 1964;Holomanova et al, 1972Holomanova et al, , 1984Pospieszny, 1984, Richmond et al, 1999.…”

“…The findings in both species studied here clearly indicated that both the spinal and cranial roots of the accessory nerve are present and prominent. Although the numbers of the spinal and cranial roots differ slightly, not only in the same animal but also between the species observed, the origin, course, branches and distribution of the accessory nerve are largely in accordance with what has been reported in the literature (Miller, 1964;Holomanova et al, 1972Holomanova et al, , 1984Pospieszny, 1984;Richmond et al, 1999), except for some mammals, including camel, giraffe and lama, that possess no spinal roots (Lesbre, 1903;Kanan, 1969;Cui-Sheng and Xie, 1998). The results are thought to be of some significance since the two models used in this study were very different and represented rare animals, even though they were mostly in line with previous literature reports.…”

“…Several textbooks (Miller, 1964;Sisson and Grossman, 1964;Dursun, 2000) and literature reports amply document the gross origin and course of the accessory nerve only in domestic animals such as equines (Tecirlioglu, 1983), ruminants (Pospieszny, 1984) and canines (Holomanova et al, 1972(Holomanova et al, , 1984Richmond et al, 1999), along with some other laboratory animals including rabbits (Kitamura et al, 1989). Recent gross structural studies, on the other hand, have focused particularly on a variety of wild species other than domestic ones.…”

Structural and functional anatomy of the neck musculature of the dog (Canis familiaris)

“…In this study, specimens were dissected immediately following euthanasia, as opposed to dissection of embalmed cadavers, and thus the entire dissection process was completed within 5–7 h from the time of death; as a result rigor mortis had only a minor effect on fascicle length measurements. Another advantage of fresh cadaver dissection was the fact that all muscles comprising the canine neck could be studied, including those which adhere closely to the vertebrae and were consequently ignored in previous studies (Kamibayashi & Richmond, 1998; Richmond et al. 1999, 2001).…”

“…This was due to the fact that these muscles were architecturally complex and closely adhered to the vertebrae. Other researchers have faced similar problems, and have stated that these muscles are so complex that they defy analysis by dissection (Kamibayashi & Richmond, 1998; Richmond et al. 1999, 2001).…”