The External, Musculoskeletal and Neuro-Anatomy of Sea Turtles
67
2.4.2.2 Respiratory Muscles
Two sheetlike respiratory muscles (testocoracoideus and testoscapularis), located
dorsally in the shoulder region, function with the posterior part of the rectus abdominus in changing body volume during ventilation. They are innervated by spinal
nerves.
2.4.2.3 Pelvic Muscles
The major posterior muscles include the puboischiofemoralis externus (a thigh
adductor, with parts that act as a protractor or retractor of the leg), the puboischiofemoralis internus, the pubotibialis, the flexor tibialis complex (thigh protractors), and
TABLE 2.2
Peripheral Nerve Innervations
Brachial Plexus Nerves
Muscle or Muscle Group
Superior brachial nerve
Tractor radii
Superficial radial nerve
Latissimus dorsi
Deep radial nerve
Latissimus dorsi, supracoracoideus,
testoscapularis
Supracoracoideus nerve
Supracoracoideus, pectoralis major, biceps
brachii (profundus and superficialis)
Subscapular nerve
Subscapularis
Axillary (deltoideus) nerve
Deltoideus (ventral parts), brachialis
Radial nerve
Latissimus dorsi, teres major, tractor radii,
triceps brachii (humeral head), respiratory
muscles
Ulnar nerve
Deltoideus (dorsal head), latissimus dorsi,
subscapularis, extensor radialis, medial flipper
muscles, extensors of digits
Median nerve
Coracobrachialis, flexor carpi ulnaris, flexors of
digits
Sacral Plexus Nerves
Crural nerve
Inguinal muscles, thigh protractors (triceps
femoris complex)
Femoral nerve
Puboischiofemoralis, dorsal hip muscles
Obturator nerve
Ventral hip muscles, caudi-ilioformoralis,
ischiotrochantericus, adductor femoris, flexor
tibialis (internus and externus), pubotibialis
complex
Ischiadicus nerve
Posterodorsal hip muscles
Sciatic nerve
Gastrocnemius, iliofemoralis, ventrolateral foot
extensors
Peroneal nerve
Triceps femoris (ambiens, femorotibialis,
iliotibialis), gastrocnemius, hind foot flexors
Tibial nerve
Flexor tibialis (internus and externus), ambiens,
pubotibialis, inguinal muscles, foot extensors
1123_C02.fm Page 67 Friday, November 15, 2002 11:16 AM
67
2.4.2.2 Respiratory Muscles
Two sheetlike respiratory muscles (testocoracoideus and testoscapularis), located
dorsally in the shoulder region, function with the posterior part of the rectus abdominus in changing body volume during ventilation. They are innervated by spinal
nerves.
2.4.2.3 Pelvic Muscles
The major posterior muscles include the puboischiofemoralis externus (a thigh
adductor, with parts that act as a protractor or retractor of the leg), the puboischiofemoralis internus, the pubotibialis, the flexor tibialis complex (thigh protractors), and
TABLE 2.2
Peripheral Nerve Innervations
Brachial Plexus Nerves
Muscle or Muscle Group
Superior brachial nerve
Tractor radii
Superficial radial nerve
Latissimus dorsi
Deep radial nerve
Latissimus dorsi, supracoracoideus,
testoscapularis
Supracoracoideus nerve
Supracoracoideus, pectoralis major, biceps
brachii (profundus and superficialis)
Subscapular nerve
Subscapularis
Axillary (deltoideus) nerve
Deltoideus (ventral parts), brachialis
Radial nerve
Latissimus dorsi, teres major, tractor radii,
triceps brachii (humeral head), respiratory
muscles
Ulnar nerve
Deltoideus (dorsal head), latissimus dorsi,
subscapularis, extensor radialis, medial flipper
muscles, extensors of digits
Median nerve
Coracobrachialis, flexor carpi ulnaris, flexors of
digits
Sacral Plexus Nerves
Crural nerve
Inguinal muscles, thigh protractors (triceps
femoris complex)
Femoral nerve
Puboischiofemoralis, dorsal hip muscles
Obturator nerve
Ventral hip muscles, caudi-ilioformoralis,
ischiotrochantericus, adductor femoris, flexor
tibialis (internus and externus), pubotibialis
complex
Ischiadicus nerve
Posterodorsal hip muscles
Sciatic nerve
Gastrocnemius, iliofemoralis, ventrolateral foot
extensors
Peroneal nerve
Triceps femoris (ambiens, femorotibialis,
iliotibialis), gastrocnemius, hind foot flexors
Tibial nerve
Flexor tibialis (internus and externus), ambiens,
pubotibialis, inguinal muscles, foot extensors
1123_C02.fm Page 67 Friday, November 15, 2002 11:16 AM