Infraspinatus Tendon Injection

Chronic tendinopathy

Cause and findings:
• Overuse
• Pain in deltoid area
• Painful: resisted lateral rotation arc on active abduction

Equipment:
Equipment:
Syringe - 2ml
Needle - 23G 1.25 inches (30mm) blue
Kenalog 40 - 20 mg
Lidocaine - 1.5 ml 2%
Total volume - 2 ml

Anatomy:
The infraspinatus and teres minor tendons insert together into the middle and lower facets on the posterior aspect of the greater tuberosity of the humerus. Placing the arm in 90° of flexion, full adduction and lateral rotation brings the tendons out from under the thickest portion of the deltoid and puts them under tension. The tendons run obliquely upwards and laterally and are, together, approximately three fingers wide at the teno-osseous insertion.

Technique:
• Patient sits or lies with supported arm flexed to right angle and held in full adduction and lateral rotation
• Identify posterior angle of acromion. Tendon insertion now lies 45° inferior and lateral in direct line with lateral epicondyle of the elbow
• Insert needle at mid-point of tendon at insertion. Pass through tendon and touch bone
• Pepper solution perpendicularly in two rows up and down into tenoosseous junction

Aftercare:
Relative rest is advised for up to 2 weeks. A progressive exercise and postural correction regime is begun when symptom-free.

Alternative approaches:
Usually a painful arc is present which indicates that the lesion lies at the tenoosseous junction. Occasionally there is no arc, when the lesion lies more in the body of the tendon. In this case, the needle is inserted more medially where there is often an area of tenderness. The same technique is applied. This lesion might occur in conjunction with subacromial bursitis. If there is a possibility of a double lesion, inject the bursa first and the tendon later if symptoms persist.