Anatomy of the bursae of the pelvis
Bursa are synovial filled cavities, anatomically designed to decrease pressure, mechanical friction and cushion sliding interfaces between associated structures. Occurring between bony prominences and the surrounding soft tissue, bursa can often become pathologically enlarged and inflamed. This results in pain and dysfunction which commonly mimics internal derangement and myotendinous disorders. Due to the complexity of the pelvic complex, there are about 20 currently characterized bursae. The authors of the present study sought to consolidate our current anatomical knowledge on the location of each bursa with respect to muscle action around the hip: flexion, extension, abduction and external rotation.
When considering hip flexion, the iliopsoas bursa is the largest bursa of the body and lies beneath the tendinous portion of the iliopsoas, lateral to pectineus muscle and medial to the ASIS. Reducing the friction of the tendon as it travels over the pelvic brim between the ASIS and illiopectineal eminence, dysfunction often presents as anterior hip pain with walking or leg crossing.
The subgluteus bursa, commonly known as the greater trochanteric bursa, is the most frequently affected bursa of the pelvis. Located between the posterior facet of the greater trochanter and gluteus maximus tendon, symptomatology includes reproducible pain with palpation, difficulty lying on affected side and with climbing stairs. The ischiogluteal bursa inconsistently lies between the gluteus maximus and ischial tuberosity. Contraction of the glute while in a seated position can reproduce signs of dysfunction. Ischial bursitis is an adventitious bursa that can develop between the hamstring origin and ischial tuberosity. Most commonly associated with tendinopathy, symptoms include chronic deep radiating pain down the posterior thigh.
Within the lateral hip compartment, the gluteofemoral bursa lies deep to the iliotibial band and TFL distal to the greater trochanteric bursa where the fibers of the gluteus maximus insert. The subgluteus medius bursa lies deep to the associated tendon at the superior aspect of the lateral facet, and the subgluteus minimus bursa lies beneath the minimus tendon at the anterior facet. Both are often present with chronic lateral hip pain, similar to the other bursae of the lateral hip compartment.
When considering the external rotators of the hip, the ischiofemoral bursa is an abnormal bursa that may become prominent between the quadratus femoris and ischium of the lesser trochanter. Symptoms of bursitis often present with deep hip and groin pain, with occasional snapping. Obturator internus bursitis is an affliction of the associated bursa lying between the internus muscle and ischium, which can be diagnosed by deep palpation. Obturator externus bursitis on the other hand, is located between its tendon and the ischiofemoral capsular ligaments.
As the authors point out, a general localized understanding of the pelvic bursa anatomy can aid clinicians in making efficient effective diagnosis of complex pain conditions of the pelvis.
> From: Friendman et al., Clin Imaging 41 (2017) 37-41(Epub ahead of print). All rights reserved to Elsevier Ltd. Click here for the online summary.