Within the shoulder complex there are 3 joints which synergistically work together to allow for movement which is needed for sporting and generic needs. The joint in the shoulder were exploring today is the Gleno-humeral joint. The Gleno-humeral joint is a ball and socket joint which allows for a large range of motion. In general, we use this joint everyday but underestimate its complexity and ability to produce the movement in which we need.Anatomy of the Gleno-humeral joint
The topographics of the gleno-humeral joint (GHJ) are: a humeral head, a fibrocartaliginous glenoid labrum (GL), glenoid cavity, ligaments and bursa’s. Overall, the fibrocartiliginous presence overlaying the glenoid rim adds joint stability to the GHJ due to an increase in the concavity-compression mechanism caused by the GL; therefore, causing a decrease in humeral head translation.
Amongst 10% of the patient population there have been three reported anatomical differentiations within the GHJ. Firstly, there are reports of a cord like middle gleno-humeral ligament with a nonexistent presence of anterior-superior labral tissue; this is commonly known as the Buford complex. Incidences of the Buford complex is said to be 2.5% within the military population.
Secondly, variations are sometimes seen with the size of the sub-labrum foreman and thirdly a variety of sub-labral recesses sizes. On the whole the Gleno-humeral joint is a complex joint which has a variety of rare anatomical differences between different people of the population. Therefore, treatments and rehabilitation strategies are always changing.The MAIN movements of the Gleno-humeral joint
Flexion Extension Medial rotation Lateral rotation Abduction Adduction Horizontal flexion Horizontal abductionPossible injuries to the joint
The shoulder is an extremely mobile joint which allows for a large range of motion. However, with a large range of motion comes the increase in likely hood of ascertaining an injury.
Commonly injuries to the shoulder occur in individuals who carry out daily overhead exercises on a regular basis (labourer). Moreover, in a sporting context damage to the shoulder joint commonly occurs from traumatic injuries to the area.In general, there are several types of injury which can occur at this specific joint:
Bankart Lesion SLAP Lesion Bicep tendinopathy Rotator Cuff Tendinopathy Multidirectional instability (caused by either or both ligament laxity and rotator cuff hypoplasia. Bursitis of one of the four bursa’s known within the typical population. (Above is only a few injuries which may happen to the gleno-humeral joint)
On the whole, the shoulder joint is a compact joint; however, it is highly susceptible to injuries due the mobility of the joint itself.References
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