A limbus labrum is as an enlarged and deformed acetabular labrum, which covers the lateral margin of a subluxed femoral head.
Seen in children and young adults.
- hip pain and labral tears
- seen mainly in settings of developmental dysplasia of the hip (DDH) or Perthes disease
It is a proliferative fibrous-tissue response at the junction of the labrum and outer wall of the acetabulum. It develops in response to the chronic eversion of the labrum and abnormal non-physiological positioning of the hip.
The histological examination of excised tissue show reparative granulation, capillary proliferation, and organized thrombi within limbus.
- thickened, enlarged labrum with heterogeneous signal on both T1WI and T2WI (as opposed to normal labrum, which is hypointense on both T1WI and T2WI).
- additional findings of DDH and Perthes disease may be seen
- 1. Ponseti IV. Morphology of the acetabulum in congenital dislocation of the hip: gross, histological and roentgenographic studies. J Bone Joint Surg Am1978;60(5):586–599.
- 2. Vitale MG, Skaggs DL. Developmental dysplasia of the hip from six months to four years of age. J Am Acad Orthop Surg2001;9(6):401–411
- 3. Rosenbaum DG1, Servaes S1, Bogner EA1, Jaramillo D1, Mintz DN1. MR Imaging in Postreduction Assessment of Developmental Dysplasia of the Hip: Goals and Obstacles. Radiographics. 2016 May-Jun;36(3):840-54.