Question
click below
click below
Question
Normal Size Small Size show me how
OCS Shoulder
Anatomy Questions
Question | Answer |
---|---|
What does the superior GH ligament restrain? | inferior translations of the humeral head when the arm is in an adducted position at the side. |
What does the middle GH ligament restrain? | anterior humeral translation with the arm in mid range of abduction up to about 45 degrees. It wil also limit ER with the arm at the side. |
What does the interior GH ligament restrain? | With ER and abduction: limits anterior translation, with IR it limits posterior translation. |
What are the proportions of true GH motion to scapulothoracic motion? | '2 to 1'. So for 180 full movement 120 is GH and 60 is scapular motion. |
What are the 3 force couples at the 'shoulder'? | 1. Deltoid/Rotator cuff 2. Upper trap/serratus andterior 3. anterior and posterior rotator cuff |
Describe the Deltoid/Rotator Cuff force couple function. | The angle of the deltoid tends to create a vertical force on the humerus. This force is offset by the horizontal force of the rotator cuff and therefore preventing impingement and allowing for stability and maximal movement of the GH. |
Describe the upper trap/serratus anterior force couple function. | The forces applied to the scapula by these two muscles assists to provide upward rotation of the scapula during shoulder elevation. |
Describe the anterior and posterior rotator cuff force couple function. | These muscles assist to create inferior dynamic stability and 'concavity' compression. They depress the humeral head and decrease liklihood of impingement. |
What is the Kibler classification system? | Describes 3 primary scapular conditions named for the portion of the scapula that is most pronounced or visible when viewed during examination. |
What is inferior angle scapular dysfunction? | the inferior border is very prominent as a result of anterior tipping of the scapula. Commonly seen with rotator cuff impingement. |
What is medial border scapular dysfunction? | the medial border is posteriorly displaced. This occurs with IR of the scapula and is seen in patients with GH joint instability. Often a component of subluxation/dislocation. |
What is superior scapular dysfunction? | early and excessive superior scapular elevation during arm elevation. Typically results from rotator cuff weakness and force couple imbalances. |
What are 3 examples of impingement tests? | Neer, Hawkins, and Yocum |
Describe a Bankart lesion | labral detachment that occurs between 2 o'clock and 6 o'clock on a right shoulder and 6-10 on the left. |
Describe a SLAP lesion | labral detachment at occurs between 10 o'clock and 2 o'clock. |
Describe a Hill-Sachs lesion | This occurs as the posterior head is impacted on the anterior gleniod when the shoulder is dislocated anteriorly. Seen as a 'divot' on X-Ray. |
Describe a reverse Hill-Sachs lesion | this occurs as the anterior humeral head impacts the posterior glenoid fossa when the shoulder is dislocated posteriorly. |
Describe Primary Compressive Disease | Primary impingement. The rotator cuff tendons are compressed between the humeral head and the acromion. |
Describe Secondary Compressive Disease | Secondary impingement. Impingement resulting from underlying instability of the GH. Increased translation of the humeral head pinches the biceps and rotator cuff. |
Describe Posterior Impingement. | With 90 abduction and 90 ER the supraspinatus and infraspinatus tendons rotate posteriorly and the tendons rub on the posterior-superior glenoid lip. |
Position for supraspinatus MMT | 90 degrees of elevation in the scapular plane (45 degrees of horizontal adduction from the coronal plane) |
Position for infraspinatus MMT | 0 elevation and 45 of IR from neutral. |
Position for teres minor MMT | 90 abduction in the scapular plane at 90 of ER. |
Position for sub-scapularis MMT | Hand behind back (gerber lift off position) |