Pubic Shears and Apparent Leg Length Discrepancies

00:00 So pubic shears are additional dysfunction that is not as frequent as the other innominate dysfunctions. Here, you’re going to have the ASIS and PSIS appearing relatively equal but a significant asymmetry at the pubic rami. So usually you'll have a superior or inferior asymmetry at the pubic rami. We are going to name the side of the positive standing flexion test the side of the dysfunction and so again pubic shears are not as common. Usually, there's severe pubic pain, may be related to some sort of trauma. I have seen these in sports athletes that have direct blow to the leg and to the region. You have your hip adductors and a lot of different muscles attaching to that region. Hyperextension of legs sometimes could kind of pull and injure the area or abdominal injuries because of its attachment to the pubic bone could cause issues there. Childbirth, because of the labor and delivery stress that is placed on the pelvis could potentially cause a pubic shear especially since mothers have the hormone relaxin. With the ligaments more relaxed, the pelvis tends to have more play in motion and movement. Sometimes severe infections could also irritate and cause issues and problems at the pubic region. Let’s take a closer look at apparent leg length discrepancies. So, any sort of asymmetry of the pelvis could potentially give us findings that look like the leg lengths are unequal. So, when we have a medial malleolus where the medial malleolus looks more inferior on one side compared to the other, it looks like an apparent leg lengthening. Certain causes include having an anterior innominate rotation and an inferior shear.

01:42 If we have a medial malleolus that looks more superior or apparent leg shortening causes include a posterior rotation or a superior shear. This is because the acetabulum on the innominate is located in the anteroinferior part and so when you have these motions and movements of the innominate, that could take the femur and the rest of the leg and move it accordingly. So, most of the time the rule of thumb is to remember the medial malleoli should follow the ASIS unless there is some sort of actual leg length discrepancy. So, let’s do another practice question here. We have a 25-year-old female comes in with complaints of back pain after falling when ice staking 2 days ago. On structural examination, you find a right positive standing flexion test, a right superior ASIS and a left inferior PSIS. What is your innominate somatic dysfunction diagnosis? So in this case, we have a right superior innominate shear. So looking at the information, we have a positive standing flexion test on the right side. So that is the side of the somatic dysfunction. So we're going to name everything for the right side. Using our hand models, we find a right superior ASIS and a left inferior PSIS. This causes us to have a right superior PSIS. So, both the ASIS and PSIS are superior on the right side at the side of dysfunction. So, that is the reason why we have a right superior innominate shear. So, this concludes our discussion on pelvic somatic dysfunction.

03:22 Hopefully, you have a better understanding now of the anatomy and the landmarks. You will be able to diagnose and treat somatic dysfunctions of the pelvis as it relates to your patients.