Related Experiment Video
Updated: May 26, 2026
06:45
Automated Joint Space Detection Improves Bone Segmentation Accuracy
Published on: November 28, 2025
Articularis genus: an anatomic and MRI study in cadavers
Stephanie J Woodley1, Christopher P Latimer, Grant R Meikle
1Department of Anatomy, Otago School of Medical Sciences, University of Otago, P.O. Box 913, Dunedin 9054, New Zealand. stephanie.woodley@anatomy.otago.ac.nz
The Journal of Bone and Joint Surgery. American Volume
|January 6, 2012
Summary
The articularis genus muscle
Area of Science:
- Anatomy
- Kinesiology
- Biomedical Imaging
Background:
- The articularis genus muscle's association with the knee joint and suprapatellar bursa is poorly understood.
- Its precise form and function remain unclear, necessitating further investigation.
Purpose of the Study:
- To define the detailed morphology of the articularis genus muscle.
- To elucidate its anatomical relationship with the suprapatellar bursa.
Main Methods:
- Investigated twenty-two human lower limbs (eleven donors) using magnetic resonance imaging (MRI) and dissection.
- Recorded muscle bundle number, length, cross-sectional area, attachment sites, and fascicle orientation.
- Utilized immunohistochemical analysis to determine muscle fiber types.
Main Results:
- The articularis genus consists of multiple muscle bundles originating from the distal femur with varied attachment sites on the suprapatellar bursa and knee capsule.
- Dissection revealed an average of seven bundles, significantly more than the four observed on MRI.
- The muscle exhibits mixed fiber types, with a variable proportion of type-I fibers.
Conclusions:
- The articularis genus displays complex and variable anatomy, challenging its identification on MRI, especially differentiating it from the vastus intermedius.
- Its anatomical complexity and association with the knee suggest it may be an overlooked cause of anterior knee pain.
Related Concept Videos
01:17Gross Anatomy of Bone
The two main features of a long bone are the diaphysis and the epiphysis.
The diaphysis is the tubular shaft that runs between the proximal and distal ends of the bone. The walls of the diaphysis are composed of dense and hard compact bone made of numerous osteons — the functional unit of the compact bone. The hollow region in the diaphysis is called the medullary cavity, which harbors the bone marrow. In infants and children, this marrow cavity is filled with red marrow, whereas in adults, it...
The diaphysis is the tubular shaft that runs between the proximal and distal ends of the bone. The walls of the diaphysis are composed of dense and hard compact bone made of numerous osteons — the functional unit of the compact bone. The hollow region in the diaphysis is called the medullary cavity, which harbors the bone marrow. In infants and children, this marrow cavity is filled with red marrow, whereas in adults, it...
01:26Joints
Joints, also called articulations or articular surfaces, are points at which ligaments or other tissues connect adjacent bones. Joints permit movement and stability, and can be classified based on their structure or function.
Structural joint classifications are based on the material that makes up the joint as well as whether or not the joint contains a space between the bones. Joints are structurally classified as fibrous, cartilaginous, or synovial.
Fibrous Joints Are Immovable
The bones of a...
Structural joint classifications are based on the material that makes up the joint as well as whether or not the joint contains a space between the bones. Joints are structurally classified as fibrous, cartilaginous, or synovial.
Fibrous Joints Are Immovable
The bones of a...
01:09Functional Classification of Joints
Functional Classification of Joints
The functional classification of joints is determined by the amount of mobility between the adjacent bones. Joints are functionally classified as a synarthrosis or immobile joint, an amphiarthrosis or slightly moveable joint, or as a diarthrosis, a freely moveable joint. Fibrous and cartilaginous joints can be functionally classified as either synarthroses or amphiarthroses, whereas all synovial joints are classified as diarthroses.
Synarthrosis
An immobile...
The functional classification of joints is determined by the amount of mobility between the adjacent bones. Joints are functionally classified as a synarthrosis or immobile joint, an amphiarthrosis or slightly moveable joint, or as a diarthrosis, a freely moveable joint. Fibrous and cartilaginous joints can be functionally classified as either synarthroses or amphiarthroses, whereas all synovial joints are classified as diarthroses.
Synarthrosis
An immobile...
01:17Structural Joints: Cartilaginous Joints
As the name indicates, at a cartilaginous joint, the adjacent bones are united by cartilage, a tough but flexible type of connective tissue. Unlike synovial joints, these types of joints lack a joint cavity and involve bones joined together by either hyaline cartilage or fibrocartilage.
There are two types of cartilaginous joints:
Synchondrosis
A synchondrosis ("joined by cartilage") is a cartilaginous joint where bones are connected by hyaline cartilage. Synchondrosis may be temporary or...
There are two types of cartilaginous joints:
Synchondrosis
A synchondrosis ("joined by cartilage") is a cartilaginous joint where bones are connected by hyaline cartilage. Synchondrosis may be temporary or...
01:09Bones of the Upper Limb: Radius
The radius is longer of the two bones that make up the human antebrachium or forearm. At the proximal end, the radius articulates with the capitulum of the humerus and the radial notch of the ulna to form the elbow joint. At the distal end, the radius articulates with the ulna via the ulnar notch, forming the distal radioulnar joint. Distally, the radius also attaches to the carpal wrist bones (scaphoid and lunate) to form the radiocarpal joint.
The radius has a nail-shaped head, and a short...
The radius has a nail-shaped head, and a short...
01:13Microscopic Anatomy of Skeletal Muscles
Skeletal muscle cells, also called muscle fibers, are distinctly elongated, multi-nucleated, slender biological units. They are packed with specialized structures designed to facilitate their primary function, which is contraction.
The muscle sarcolemma is a plasma membrane enclosing each muscle cell that conducts electrical signals called action potentials. The sarcolemma extends into the cell to form T-tubules, ensuring the neural impulses are uniformly distributed across the entire muscle...
The muscle sarcolemma is a plasma membrane enclosing each muscle cell that conducts electrical signals called action potentials. The sarcolemma extends into the cell to form T-tubules, ensuring the neural impulses are uniformly distributed across the entire muscle...