KINEMATIC CHAIN

The movement of one joint may require the motion over the proximal and distal joints, and sometimes it may not be required.

Two types of kinematic chains are present.

1. Closed kinematic chains (CKC)
2. Open kinematic chains (OKC)

Closed Kinematic Chain
In human body the joints are having interlink with each other, so the motion occurs in one particular joint causes motion over the other joints in predictable manner. In the closed kinematic chain the proximal and distal joint will be moving to produce the movement over one particular joint.

Example: (I) Performing the sit-ups and (2) performing the push-ups.

In the first example the hip joint flexion and the ankle joint dorsiflexion occurs to produce the flexion over the knee to go for the sitting posture. The proximal joint (hip) is moving towards the distal (ankle) joint but the distal joint is fixed without any movement.

In the second example the shoulder extension and wrist extension produce the elbow flexion to perform the push-ups. The shoulder joint moves towards the fixed wrist.

Open Kinematic Chain
The movement occurring independently and not in predictable manner. The distal joint moving and the proximal joint will be fixed with¬out any motion

Example:
a. In shoulder 90° flexion, performing the elbow flexion and extension movement
b. In standing posture, the leg is lifted from the ground and performing the knee flexion and extension movement.

Comments

Post a Comment

Popular posts from this blog

Physiotherapy: a first contact, autonomous, client-focused health profession in Canada

Background Physiotherapy is a first contact, autonomous, client-focused health profession dedicated to: • Improving and maintaining functional independence and physical performance, • Preventing and managing pain, physical impairments, disabilities and limits to participation; and • Promoting fitness, health a nd wellness. The heart of the physiotherapy profession is understanding how and why movement and function take place. Physiotherapists are independent and caring health professionals who seek to provide safe, quality client-centred physiotherapy through a commitment to service availability, accessibility and excellence. The profession continues to be shaped by scientific evidence and the education and competence of the physiotherapists delivering the services. Physiotherapy is grounded in the belief that, to be effective, its services must respond to the changing needs of populations. Primary Functions of physiotherapists Physiotherapists apply a collaborative and rea...
Read more

Bone Structure and Growth (Quick Review)

A. Bone is a living tissue that renews itself. B. Structure: Compact and Spongy i. Compact bone contains bone cells (osteocytes) in lacunae, which are tiny chambers arranged in concentric circles around Haversian canals. The canals contain blood vessels and nerves. ii. A matrix that has protein fibers of collagen and mineral deposits of calcium and phosphorus salts separates lacunae. iii. Spongy bone has bony bars and plates separated by irregular spaces. iv. Spongy bone is lighter than compact bone. v. Spaces in spongy bone are filled with red bone marrow. Located in hipbone and sternum of adult. vi. Bone marrow is where RBC's are made. vii. The cavity of long one has yellow bone marrow where fat is stored. viii. Bone covered by periosteum (outer membrane). ix. Osteocytes have canaliculi. A. Bone growth/constant renewal i. During prenatal development skeleton is made of cartilage. ii. Replaced by bone. Osteoblast (bone forming cell) does this. iii. Primary ost...
Read more

ACTIVE AND PASSIVE INSUFFICIENCY

In one joint muscle the movement may not be restricted by the proximal or distal joint motion. But it is not possible in the two or multi-joint muscles, the ROM may be changing depends on the proximal and distal joint movement. If the muscles are crossing more than one joint, there is possibility for active and passive insufficient said by Brunnstrom. Active ins ufficiency The muscle cannot go for further shortening while performing the activity around the joints, which the muscle crosses. It occurs to the agonists. Example: Flexor compartment muscles of the forearm. These muscles responsible for elbow flexion, MCP flexion PIP and DIP flexion. If the above said movements are done in the same sequence, the person feels difficult in flexing the MCP and finger after flexing the elbow and wrist, because the muscles are already shortened by the elbow and wrist flexion. So, further shortening is difficult, this is called as active insufficiency (Tenodesis). Passive Insu...
Read more