This blog is a synopsis of the excellent review on the topic by Ludewig and Reynolds (2009). Assessment During shoulder flexion the scapula should upwardly rotate and posteriorly and externally rotate at the acromioclavicular joint (Fey et al 2007, van der Helm 1994). The clavicle elevates and increasingly retracts during shoulder flexion. For typical alterations in shoulder pathologies see (Ludewig and Reynolds 2009). Treatment Which muscles to strengthen? The serratus anterior is the only muscle that can produce all three desired scapula motions during shoulder flexion and abduction (Ludewig...