Joints of Extremities

 

Learnig & Test Objectives

  1. Classification of joints.
  2. Joints mobility and range of motion.
  3. Structural composition of joints.
  4. Ligaments attachments.
  5. Identifying structures on radiographs and constructing an illustrating schemes of the listed required figures. 

Description of the test

The test is held by the general rules of written tests (see Continuous Testing – Organisation).

Clinical notes

Osteoarthrosis is a degenerative joint disease that has a predilection for the large weight bearing joints. The most commonly affected joints are the hip (coxarthrosis), knee (gonarthrosis), shoulder (omarthrosis) and vertebral column (spondylarthrosis).  

Arthritis is an inflammatory disease that can affect any of the joints of the human body. 

Loose bodies / joint mice (mus intraarticularis) are small pieces of cartilage or bone that have broken off from the articular surface and are freely moving in the joint cavity. They typically occur in osteoarthritis and osteochondrosis dissecans. Loose bodies can prevent the joint from moving, causing joint restriction. 

Bursitis is a term used for painful inflammation of synovial bursa that is not caused by infection nor an autoimunne process. It may originate after long-term overloading, high pressure or after injury. 

Violent impacts transferred from the upper limb lead more often to a fracture of the clavicle than to a dislocation of the sternoclavicular joint, because of firmness of the articular capsule and ligaments. 

Due to its small articular fossa and large articular head, the shoulder joint is frequently dislocated. An anterior inferior shoulder dislocation is the most frequent type of shoulder dislocation, occuring in more than 90 % of cases. 

The anular ligament of the radius is not fully developed in children until the age of 5 to 6. Under weight of the forearm, a subluxation of the humeroradial joint can occur. This condition is termed painful pronation (pronatio dolorosa).

Developmental dysplasia of the hip (DDH) is a congenital deformity of the hip joint which, if not treated, causes orthopaedic problems throughout life. It is characterised by a misshapen acetabulum and/or head and neck of the femur. This causes a misalignment of the ‘bone-to-bone’ contact between the articular head and fossa. All newborns are screened for DDH after birth with a specialised examination that includes ultrasound.

Total hip replacement (endoprosthesis) is an orthopaedic procedure that replaces the articular head and fossa of the hip joint with an artificial prosthesis. Severely damaged hips are indicated for this operation, such as occur in osteoarthrosis or after injuries.

The unhappy triad is a term given to concomitant damage to the anterior cruciate ligament, medial meniscus and tibial collateral ligament. 

The menisci, anterior cruciate ligament and collateral ligaments are the most predisposed structures of the knee to be injured. The anterior cruciate ligament is injured ten times more frequently than the posterior cruciate ligament.

The tibiofibular syndesmosis is a very firm synarthrosis. A trauma to the leg is much more likely to cause dislocation of the ankle than rupture of the tibiofibular syndesmosis. 

Injuries of the collateral ligaments of the ankle represent some of the most frequent types of sport injuries. The medial collateral ligament is firmer than the lateral and so is injured less often. A sprained ankle, the most common type of ankle injury, is caused by a tear in the anterior inferior talofibular ligament.

Exarticulation of the distal part of the foot can be performed along the Chopart's or Lisfranc's joint lines.

Hallux valgus is a deformity of the big toe characterised by a lateral deviation of the big toe towards the other toes. It can occur secondarily due to a varus deformity of the 1st metarsal or to degenerative changes of the 1st metatarsophalangeal joint.

Pes transversoplanus is a type of flat foot caused by the collapse of the transverse arch of the foot.

 

Other interesting notes

Abbreviations of some joints:
SC – sternoclavicular joint
AC – acromioclavicular joint
GH – glenohumeral joint
PIP –proximal interphalangeal joint
DIP – distal interphalangeal joint
SI – sacroiliac joint

It is best to fix joints in the middle position when treating fractures, unless the type of injury needs a special type of fixation.

Fornix humeri is a fibrous arch above the shoulder joint shaped by the coracoacromial ligament. Abduction of the arm greater than 90° is limited by the greater tubercle coming into contact with the fornix humeri. The arm can only be abducted further by concomitant external rotation of the scapula. 

The shoulder is a collective term for:
1 The glenohumeral joint
2 The acromioclavicular joint
3 The sternoclavicular joint
4 The functional connection between the scapula and thorax (‘scapulothoracic joint’)
Movements of the shoulder are facilitated by movements at these four connections.

The inferior pubic ligament (ligamentum pubicum inferius), is so strong that it can hold the two pubic bones together in the absence of the pubic symphysis.

The iliofemoral ligament is short at birth but gains length during life. It is the strongest ligament in the human body. In newborns it keeps the thighs in a typical position (flexion, abduction and external rotation).

The key to Chopart's joint (clavis articulationis tarsi transversae) is a clinical term for the bifurcated ligament.

 

Pictures to draw

Scheme of the joints of the hand, anterior view.

Superior view of a transverse section of the knee joint (fibrous capsule, synovial membrane, ligaments, menisci).

Scheme of the joints of the foot, superior view (including functional joints).

 

Radiographical images

Radiographs of the bones and joints of the upper extremity

Radiographs of the bones and joints of the lower extremity

Created: 22. 10. 2016 / Upraveno: / Odpovědná osoba: MUDr. Azzat Al-Redouan