There continues to be a plethora of research and dialogue on the femoral acetabular impingements (FAI), the intra-articular impingements. But we must not forget about the extra-articular impingements about the hip. A common one we see is the Ischiofemoral variety whereby the quadratus femoris muscle gets pinched between the ischial tuberosity and the femur. We wrote about it, see the link below. This one gets mistake for proximal hamstring tendonopathies by some we suspect. We suspect, however this is pure speculation, that the two most common are #1 and #3.
This article outlines some of the common extra-articular impingement syndromes:
1) Ischiofemoral impingement: as we discuss in our article
"2) Subspine impingement: mechanical conflict occurs between an enlarged or malorientated anterior inferior iliac spine and the distal anterior femoral neck.
3) Iliopsoas impingement: mechanical conflict occurs between the iliopsoas muscle and the labrum, resulting in distinct anterior labral pathology.
4) Deep gluteal syndrome: pain occurs in the buttock due to the entrapment of the sciatic nerve in the deep gluteal space.
5) Pectineofoveal impingement: pain occurs when the medial synovial fold impinges against overlying soft tissue, primarily the zona orbicularis. "
Current concepts in the diagnosis and management of extra-articular hip impingement syndromes. Nakano N1, Yip G1, Khanduja V2.
Int Orthop. 2017 Jul;41(7):1321-1328. doi: 10.1007/s00264-017-3431-4. Epub 2017 Apr 11.