The hip joint is a Diarthroidal Joint whose unique anatomy enables it to be both extremely strong and amazingly flexible, so it can bear weight and allow for a wide range of movements. The primary function of the hip joint is to provide dynamic support to the weight of the body/trunk while facilitating force and load transmission from the axial skeleton to the lower extremities, allowing for ambulatory and mobility functions.
The hip is located where the head of the femur, or thighbone, fits into a rounded socket (Acetabulum)of the pelvis. This ball-and-socket construction allows for three distinct types of flexibility:
The shoulder joint is among the most flexible joints in your body. It is a ball-and-socket joint and is made up of three bones: the upper arm bone (humerus), shoulder blade (scapula), and collarbone (clavicle).
The ball at the top end of the arm bone fits into the small socket ‘glenoid’ of the shoulder blade to form the shoulder’s glenohumeral joint. This is surrounded by the soft tissue labrum. The articular cartilage which is a smooth, durable surface on the head of the arm bone, along with the thin inner lining synovium of the joint allows the smooth motion of the shoulder.
The shoulder joint also comprises a thin sheet of fibers called capsule that surrounds the shoulder joint, allowing a wide range of motion, yet provides stability. A rotator cuff is a group of muscles and tendons that attach your upper arm to your shoulder blade and is an integral part of the joint.
The rotator cuff covers the shoulder joint and joint capsule. The muscles attached to the rotator cuff enable one to move and rotate their arms in multiple directions such as front, above, to the side, and behind your body.
But with this flexibility, the shoulder also becomes vulnerable to instability and injury. Timely and proper diagnosis helps avoid severe repercussions later and treat the joint before the condition worsens. If the complication or ailment in the shoulder is quite serious, then the Joint Replacement Surgeon may go for open shoulder surgery instead of arthroscopy.
The elbow is the synovial joint between the upper and lower parts of the arm. It is the point of articulation of three bones: the humerus of the arm and the radius and the ulna of the forearm. These bones give rise to two joints: