I often hear the terminology open-packed and close-packed joint positions used in the clinic. In general, clinicians know to mobilize in the open-packed position and avoid manipulation in a close-packed position, but what else should we know about these terms? Is there any other clinical significance to the open v. close-packed positions? In this post I will review these 2 positions and discuss the clinical relevance of each.
How Should PT's Interpret Open vs Close-Packed Clinically?
As I mentioned above, it is important to start your joint assessment and treatment in the open-packed position. Since the joint has the most available room for movement, mobilizations are best tolerated in this position. For example, the open-packed position of the knee is 25 degrees of flexion. The close-packed position is full extension. At 25 degrees of flexion the knee is loose- one can assess varus and valgus ligament stress testing or check tibial IR/ER mobility in this position. Biomechanically, the knee is 'unlocked.' Following an injury, the body favors this position because there is space for swelling and other fluid to accumulate within the joint. As the patient's ROM improves, pain decreases, and the swelling subsides, the clinician can start to mobilize the joint in other positions of flexion and extension as needed.
Additionally, understanding the open and closed packed positions is essential when performing manipulations. We want to manipulate a joint in the open-packed position, but often times we cannot target a specific joint unless we lock out or close-pack the surrounding joints. For example, when performing a prone SIJ distraction manipulation, the hip needs to be placed in extension, abduction, and internal rotation. These three movements are the close-packed position of the hip joint. You must lock out the hip so you do not manipulate it when you are targeting the SIJ.
Each joint has a different open and close packed position and being able to quickly recall that position will make you a more efficient clinician. If you do not understand the open and close-packed positions of regional joints, the specificity of your techniques will decrease.