EP3.26 Greater Trochanteric Enthesopathy with Abductor Tendon Tearing as A Novel Etiology of Coxa Saltans Externa

Abstract

External coxa saltans, or lateral snapping hip arises from the abnormal movement of the iliotibial band (ITB) over the greater trochanter. The ITB has two major muscular components: the tensor fascia lata and the gluteus maximus. Thickening of the posterior aspect of the ITB or the anterior aspect of the gluteus maximus as it traverses over the greater trochanter perpetuates the snapping phenomenon. Several open and endoscopic techniques have been described to successfully treat external coxa saltans, with release of the iliotibial band being the accepted treatment approach.

This case report presents a previously undescribed etiology of coxa saltans externa whereby trochanteric enthesopathy in the setting of chronic abductor tendinopathy and tendon tearing resulted in pathologic snapping of the iliotibial band over the enthesopathic prominences on the greater trochanter (Video 1). This novel etiology required a novel approach to address the pathologic snapping. Rather than iliotibial band release, the appropriate treatment in this case required resection of the trochanteric enthesopathy with abductor tendon repair followed by complete closure of the iliotibial band which resulted in the resolution of the patient’s symptoms (Figure 1, Video 2). Patient reported outcomes measures (pre/post) including HOOS, PROMIS pain interference, PROMIS physical function and global pain scores demonstrated significant improvement 33 months post-surgery.

Recognition of this unique etiology of external coxa saltans ensures the appropriate treatment is employed to address the underlying pathology. The ITB is an important stabilizer of the hip and the tensor fascia lata an important accessory abductor of the hip. Release of the iliotibial band in the setting of underlying abductor dysfunction could potentially lead to further dysfunction and ongoing mechanical symptoms. When patients present with external coxa saltans in the setting of underlying abductor dysfunction and trochanteric enthesopathy, consideration should be given to resection of the enthesophytes with abductor tendon repair as opposed to open or endoscopic ITB release alone.