injuries poisoning
How To Reduce Anterior Shoulder Dislocations Using External Rotation (Hennepin Technique)
Step by Step Description of the Hennepin Technique
Neurovascular examination Do a pre-procedure neurovascular examination of the affected arm, and repeat the examination after each reduction attempt. Generally, testing motor function is more reliable than testing sensation, partly because cutaneous nerve territories may overlap. Assess the following: Distal pulses, capillary refill, cool extremity (axillary artery) Light touch sensation of the lateral aspect of the upper arm (axillary nerve), thenar and hypothenar eminences (median and ulnar nerves), and dorsum of the 1st web space (radial nerve) Shoulder abduction against resistance, while feeling the deltoid muscle for contraction (axillary nerve): However, if this test worsens the patient's pain, omit it until after the shoulder has been reduced Thumb-index finger apposition ("OK" gesture) and finger flexion against resistance (median nerve) Finger abduction against resistance (ulnar nerve) Wrist and finger extension against resistance (radial nerve) Intra-articular analgesia If a cooperative patient chooses to try reduction without analgesia, only one such attempt should be made. To give intra-articular analgesia: The needle insertion site is about 2 cm inferior to the lateral edge of the acromion process (into the depression created by the absence of the humeral head). Swab the area with antiseptic solution, and allow the antiseptic solution to dry for at least 1 minute. Optional: Place a skin wheal of local anesthetic (≤1 mL) at the site. Insert the intra-articular needle perpendicular to the skin, apply back pressure on the syringe plunger, and advance the needle medially and slightly inferiorly about 2 cm. If any blood is aspirated from the joint,hold the needle hub motionless, switch to an empty syringe, aspirate all of the blood, and re-attach the anesthetic syringe. Inject 10 to 20 mL of anesthetic solution (eg, 1%lidocaine). Wait for analgesia to occur (up to 15 to 20 minutes) before proceeding. The practitioner adducts the dislocated arm with the elbow held at 90°. The arm is then externally rotated slowly (eg, over 5 to 10 min) to allow time for muscle spasms to resolve. Reduction commonly occurs at 70 to 110° of external rotation. Reduce the shoulder — Hennepin method Using one hand, hold the affected upper arm adducted against the patient's side. Using your other hand, gently hold the patient’s wrist, keeping the elbow flexed 90° and the forearm neutral (ie, thumb pointing cephalad). Instruct the patient to try to relax the arm as you guide it through the maneuver. Slowly and gently, rotate the arm externally, by applying minimal force to the volar surface of the wrist. Work as if you were guiding the arm through passive external rotation. Continue until the forearm is near the coronal plane (ie, 90° of external rotation). If the patient experiences pain or muscle spasm,pause momentarily and keep the arm motionless, so the patient can focus on relaxing and allowing muscle spasms to resolve. Reduction commonly occurs at 70 to 110° of external rotation and may take up to 5 or 10 minutes. Reduction is frequently subtle and may be difficult to identify (the perceptible "clunk" that occurs with more forceful reduction methods may be absent). If reduction is not achievedat this point, maintain the arm’s position and apply slow, gentle traction at the elbow (do not apply traction if a neurovascular injury is suspected). maintain the arm’s external rotation and gentle traction, and slowly abduct the arm to the overhead position while pushing the humeral head upward into the glenoid using your thumb in the axilla. (This is a variant of the Milch method ( Reference ), the steps of which are gentle full abduction, slight axial traction and external rotation, plus, if needed, upward pressure via thumb or fingers directly to the humeral head.) Restore the arm to the pre-reduction position (adducted, non-rotated). If reduction has failed to occur thus far, sometimes it will occur as the arm is rotated back internally. 