On Wednesday, we discovered that the “Cinderella” of our hip flexors, the bi-articular sartorius, could be an over-looked cause of muscular pain at the anterior hip and medial knee.
Over and above an acute injury to the muscle, we should also consider how our postural and alignment habits contribute to sartorius-related pain and dysfunction.
Data from national surveys indicates that adult Americans spend 55% of their day in sedentary pursuits. This translates into more than 7 hours a day sitting for many of us, an activity (or lack thereof!) that has been linked to a 49% increase of death from all causes and a whopping 147% increase in the risk of having a cardiovascular event. As well as clearly having an effect at the metabolic level, sitting for seven or more hours a day certainly has an impact at the muscular level. Chair-sitting places the hips in 90 degrees of flexion, and spending a lot of our day in this position may shorten the muscles that connect the thigh to the trunk (psoas), the thigh to the pelvis (iliacus), and the sartorius as it works in the background to assist hip flexion. Considering that most of us also have the tendency to cross one leg over the other whilst sitting and we start to see side-to-side imbalances in sartorius muscle length.
Combine the lack of proper hip extension caused by shortened hip flexors with the inherent weakness in the muscles of the foot caused by poor footwear choices and a lack of ‘bare’ foot time, and even the time we spend out of sitting− standing, walking, and running− can lead to less than optimal loading patterns on certain joints and result in overuse injuries and pain.
If you are reading this, and feeling quite pleased with yourself as someone who has given up their chair and adopted a cross-legged position on the floor, then well-done for changing position, but consider again the actions of our forgotten hip flexor sartorius, that not only flexes the hip (and knee) but also laterally rotates and abducts the hip. Yes, that would be you, sitting with your legs crossed.
So to all your favourite hip flexor stretches, why not add ones that combine extension with adduction and internal rotation to specifically target the sartorius? To work on rehabilitating and strengthening a weak sartorius Half Happy Baby Mini Vini (as shown in the video below), will take your hip and knee through all the directions of movement required to correctly exercise your tailor’s muscle again and provide sartorius pain relief.
 Matthews CE, Chen KY, Freedson PS, et al. Amount of time spent in sedentary behaviors in the United States, 2003-2004. Am J Epidemiol 2008; 167:875-81.
 Wilmot EG, Edwardson CL, Achana FA, et al. Sedentary time in adults and the association with diabetes, cardiovascular disease and death: systematic review and meta-analysis. Diabetologia (2012) 55:2895–2905