Temporomandibular Joint (TMJ) <ul><li>Combination of a hinge and gliding joint </li></ul><ul><li>Reinforced by 3 major extrinsic ligaments </li></ul><ul><li>Only synovial joint in skull </li></ul><ul><li>Depression/elevation </li></ul><ul><li>Protraction/retraction </li></ul><ul><li>Lateral movements </li></ul>
The temporomandibular joint is formed by the mandibular condyle and the mandibular fossa of the temporal bone. It is supported by ligaments.
An articular disc separates the bones within the joint capsule. The movement of this disc may create clicking or popping sounds.
The TMJ allows depression/elevation, protraction/retraction, and lateral rotary movements.
Mouth splints can prevent teeth grinding which can lead to TMJ syndrome
Close-up of mouth splint used to prevent TMJ syndrome
ACCORDING TO THE CLINICAL VIEW IN YOUR TEXT, TMJ DISORDER CAN CAUSE WIDESPREAD DISTRIBUTION OF PAIN IN THE HEAD. WHY? A SPREAD OF INFLAMMATORY CHEMICALS VIA THE LYMPHATIC SYSTEM B AVASCULAR NECROSIS C AUTOIMMUNE DISEASE D PSYCHOSOMATIC PAIN FROM OCCIPITAL LOBE OF THE CEREBRUM E IRRITATION OF THE TRIGEMINAL NERVE
The intervertebral discs form an amphiarthrotic symphysis between one vertebral body and the next. The articulation between the articular processes form amphiarthotic synovial gliding (planar) joints .
The combined effect of slight movement between all the gliding joints is considerable movement of the spine.
The sternoclavicular joint is formed where the clavicle articulates with the manubrium. Depending on the reference source it is a either a diarthrotic synovial gliding joint OR a diarthrotic synovial saddle joint .
Sternoclavicular joint has an articular disc .
Mike Bond putting great stress on his sternoclavicular joints
Rotator cuff (musculotendinous cuff) is formed by tendons of the infraspinatus, subscapularis, supraspinatus, and teres major. It is weak inferiorly.
The coracohumeral ligament, glenohumeral ligaments, and the transverse humeral ligament all help stabilize the glenohumeral joint.
There are numerous bursae and tendon sheaths associated with the shoulder (glenohumeral) joint.
WHICH OF THE FOLLOWING IS A CORRECT STATEMENT? A GLENOHUMERAL DISLOCATIONS (LUXATIONS) INITIALLY OCCUR SUPERIORLY AND THEN THE HUMERAL HEAD SHIFTS POSTERIORLY. B THE LIGAMENTUM NUCHAE CONNECTS TO THE VERTEBRA PROMINENS C THE FIBROCARTILAGE PADS BETWEEN VERTEBRAL BODIES FORM SYNCHONDROSES D THE ARTICULATION BETWEEN VERTEBRAL ARTICULAR PROCESSES ARE BIAXIAL SYMPHYSES E. THE MUSCULOTENDINOUS CUFF IS FORMED BY INTEROSSEOUS MEMBRANE
The humeroulnar joint ( between trochlea and trochlear notch) is a hinge joint. The humeroradial joint ( between capitulum and radial head) is considered by some to be a gliding joint. Anterior view
A fibrocartilage acetabular labrum deepens the concavity of the acetabulum and helps stabilize the coxal (acetabulofemoral) joint
Strong ligaments, a strong joint capsule, and powerful muscles help to stabilize the acetabulofemoral joint
The retinacular fibers support the joint capsule and contain arteries that supply most of the blood to the neck and head of the femur The ligament of the head of the femur (ligamentum teres) contains a small artery that supplies some of the blood to the head of the femur.
Fracture of the neck of the femur Read about fracture of the femoral neck in the clinical view in the text
The quadriceps femoris tendon inserts onto the patella, which is embedded in this tendon The patellar ligament extends inferiorly from the patella and attaches to the tibial tuberosity
The tibiofemoral joint is stabilized by the lateral (fibular) collateral ligament and by the medial (tibial) collateral ligament . The LCL is NOT attached to the meniscus. Right knee, anterior view
In varus displacement of the knee (hyperadduction of the lower leg), the distal segment (lower leg) is abnormally deviated medially. This is normally prevented by the lateral (fibular) collateral ligament .
The tibiofemoral joint is stabilized by the lateral (fibular) collateral ligament and by the medial (tibial) collateral ligament . Right knee, anterior view
In valgus displacement of the knee (hyperabduction of the lower leg), the knee is driven medially while the lower leg is deviated laterally. This is normally prevented by the medial (tibial) collateral ligament.
attached The medial collateral ligament is attached to the medial meniscus . This means if the MCL tears the medical meniscus also tears. Right knee, anterior view
The medial meniscus and the lateral meniscus are made of fibrocartilage and help stabilize the knee and act as cushions. Note the MCL is attached to the medial meniscus. attached Right knee, anterior view
The menisci help to pad and stabilize the knee
More deeply the tibiofemoral joint is stabilized by the posterior cruciate ligament and by the anterior cruciate ligament .
Note that the posterior cruciate ligament is tight (taut) when the tibiofemoral joint is flexed while the anterior cruciate ligament is tight (taut) when the tibiofemoral joint is extended . Most knee injuries occur when the knee is extended (anterior cruciate ligament is tight) so it is commonly ruptured (ruptured ACL) by hyperextension or lateral displacement when leg is extended. ACL tight PCL tight
Humans are bipedal animals. An important aspect in walking and standing is the ability to “lock” the knees . This is possible because at full extension the tibia rotates laterally so as to tighten the ACL and squeeze the meniscus between the tibia and femur. This mechanism permits a person to stand for long periods without using or tiring the muscles of the leg.
The tibiofemoral joint (knee) is very vulnerable to injury. Read the clinical view in the text.
Valgus deviation of the knee (hyperabduction of lower leg))
Valgus stress to the knee (hyperabduction of the lower leg) can rupture the MCL, the medial meniscus, and, if enough displacement occurs, the ACL and the PCL. (medial)
An allograft replacement of the ACL uses materials from another person (cadaver)
An autograft replacement uses your own tissues, such as the middle portion of the patellar ligament
An autograft replacement can also use a portion of your hamstring tendons. They are removed, braided, and used to replace the ACL.
There are numerous bursae associated with the knee. Two of them are shown here.
WHICH OF THE FOLLOWING WOULD BE INJURED IN THE KNEE BY HYPERABDUCTION OF THE LOWER LEG (VALGUS DEVIATION)? A MENISCUS B LATERAL COLLATERAL LIGAMENT C PATELLAR LIGAMENT D RUPTURED RETINACULAR FIBERS E ALL OF THE ABOVE
Read about the different types of arthritis in the clinical view in your text.
WHICH OF THE FOLLOWING IS ASSOCIATED WITH RHEUMATOID ARTHRITIS? A SUPPRESSION BY DIFFERENT HLA PROTEINS B URIC ACID CRYSTALS ACCUMULATING IN SYNOVIAL FLUID C OVEREXERCISE OR ADVANCING AGE D MOST COMMON TYPE OF ARTHRITIS E COMMONLY TREATED WITH SYNGENETIC GRAFTS OR XENOGRAFTS