System: Musculoskeletal

Flexor Pollicis Brevis

Flexor Pollicis Brevis The structure indicated is the flexor pollicis brevis muscle of the hand. The flexor pollicis brevis muscle is one of the intrinsic muscles of the hand that belongs to the thenar group. The thenar group of intrinsic hand muscles consist of three muscles: Abductor pollicis brevis Flexor pollicis brevis Opponens pollicis All the intrinsic muscles of the hand, except the thenar muscles and the lateral two lumbrical muscles are innervated by the deep branch of the ulnar nerve. The thenar muscles and the lateral two lumbrical muscles are innervated by the median nerve.  A useful mnemonic for …

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flexor pollicis brevis

First Lumbrical

First Lumbrical The structure indicated is the first lumbrical muscle of the hand. The lumbricals belong to the intrinsic group of muscles which act on the hand. The intrinsic muscles include the following muscles/groups: Thenar group (act on thumb) Hypothenar group (act on little finger) Adductor pollicis Lumbricals Interossesus muscles Palmaris brevis All the intrinsic muscles of the hand, except the thenar muscles and the lateral two lumbrical muscles are innervated by the deep branch of the ulnar nerve. The thenar muscles and the lateral two lumbrical muscles are innervated by the median nerve.  A useful mnemonic for remembering this …

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first lumbrical

Medial Cuneiform Bone

Medial Cuneiform Bone The structure indicated is the medial cuneiform bone of the foot. The foot contains three groups of bones: Tarsals Metatarsals Phalanges The medial cuneiform bone is one of seven tarsal bones. There are three groups of tarsal bones: Proximal group Intermediate group Distal group The medial cuneiform bone belongs to the distal group of tarsal bones. There are three cuneiform bones: Lateral cuneiform Intermediate cuneiform Medial cuneiform Anteriorly they articulate with the medial three metatarsals. Posteriorly they articulate with the navicular bone, and laterally they articulate with the cuboid bone. Learn more about the bones of the …

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medial cuneiform

Triquetral Bone

Triquetral Bone The structure indicated is the triquetral bone of the hand. There are three groups of bones in the hand: Carpal bones (8 in total) Metacarpal bones Phalanges The carpal bones are separated into two rows: Proximal row Distal row The triquetral bone is one of four bones in the proximal row of carpals (scaphoid, lunate, triquetral, pisiform). The triquetral bone is located medially in the hand and articulates with the pisiform bone, the hamate and lunate bones. On the medial aspect of the volar surface of the triquetral bone is a facet for articulation with the small pisiform …

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triquetral bone

Trapezoid Bone

Trapezoid Bone The structure indicated is the trapezoid bone of the hand. There are three groups of bones in the hand: Carpal bones (8 in total) Metacarpal bones Phalanges The carpal bones are separated into two rows: Proximal row Distal row The trapezoid bone is located in the distal row of carpal bones. There are four bones in the distal row: Trapezium Trapezoid Capitate Hamate It’s easy to confuse the location of the trapezoid with the adjacent and similarly named trapezium bone. A way to remember where the trapezium is located is that trapezi-UM rhymes with thUMB, and therefore articulates …

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trapezoid bone

Intermediate Cuneiform

Intermediate Cuneiform The structure indicated is the intermediate cuneiform bone of the foot. The foot contains three groups of bones: Tarsals Metatarsals Phalanges The intermediate cuneiform bone is one of seven tarsal bones. There are three groups of tarsal bones: Proximal group Intermediate group Distal group The intermediate cuneiform bone belongs to the distal group of tarsal bones. There are three cuneiform bones: Lateral cuneiform Intermediate cuneiform Medial cuneiform Anteriorly they articulate with the medial three metatarsals. Posteriorly they articulate with the navicular bone, and laterally they articulate with the cuboid bone. Learn more about the bones of the foot in …

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intermediate cuneiform

Opponens Digiti Minimi

Opponens Digiti Minimi The structure indicated is the opponens digiti minimi muscle. The opponens digiti minimi muscle is one of the intrinsic muscles of the hand that belongs to the hypothenar group. The hypothenar group of intrinsic hand muscles consist of three muscles: Abductor digiti minimi Opponens digiti minimi Flexor digit minimi brevis All the intrinsic muscles of the hand, except the thenar muscles and the lateral two lumbrical muscles are innervated by the deep branch of the ulnar nerve. The thenar muscles and the lateral two lumbrical muscles are innervated by the median nerve.  A useful mnemonic for remembering …

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opponens digiti minimi

Rectus Femoris

Rectus Femoris The structure indicated is the rectus femoris of the quadriceps group of thigh muscles. The rectus femoris is one of the muscles that makes up the quadriceps femoris, and is contained in the anterior compartment of the thigh. The muscles of the anterior compartment are all innervated by the femoral nerve and serve generally to extend the leg at the knee joint. The four muscles that make up the quadriceps femoris are the: Rectus femoris Vastus lateralis Vastus medialis Vastus intermedius In addition to the quadriceps muscles, the Sartorius muscle is also located in the anterior compartment together …

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rectus femoris

Lamina

Lamina The structure indicated is the lamina of the vertebra. The typical vertebra consists of the following features: Vertebral body Vertebral arch (neural arch) consisting of lamina and pedicle Spinous process Transverse process Vertebral foramen (collectively form vertebral canal) Superior and inferior articular processes Superior and inferior vertebral notches The vertebral arch is formed from two pedicles and two laminae. The pedicles attach on either side to the posterolateral aspects of the vertebral body and unite posteriorly with the laminae which complete the vertebral arch. The laminae provide attachment for the ligamentum flavum, which connect adjacent laminae along the length …

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lamina

Spinous Process of Vertebra

Spinous Process of Vertebra The structure indicated is the spinous process of the vertebra. The typical vertebra consists of the following features: Vertebral body Vertebral arch (neural arch) consisting of lamina and pedicle Spinous process Transverse process Vertebral foramen (collectively form vertebral canal) Superior and inferior articular processes Superior and inferior vertebral notches The vertebral arch extends posteriorly from the vertebral body, comprised of two pedicles which extend from the posterolateral aspects of the vertebral body to join the two laminae on either side which complete the vertebral arch and enclose the vertebral foramen. Projecting posteriorly in the midline from …

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spinous process