Fig 1.
Schematic representation of labral tear grades in patients with hip dysplasia.
(A) The left hip joint from behind. (B) Arthroscopic view of the left hip through the anterolateral portal using a 70° arthroscope. (C) Grade 1: partial delamination or blistering of the labrum with minimal fraying at the CLJ. (D) Grade 2: labral tears with CLJ disruption, but no instability. (E) Grade 3: unstable labral tears with CLJ and CLR disruption, but no labral displacement. (F) Grade 4: unstable labral tears with CLJ and CLR disruption, which displaced the labrum laterally. (L, labrum; FH, femoral head; AC, acetabular cartilage).
Fig 2.
Arthroscopic findings and MRI features of grade 1 labral tears.
(A) Arthroscopy showing partial delamination with fraying at CLJ, with (B) MRI showing no definite labral pathology. (L, labrum; FH, femoral head; AC, acetabular cartilage).
Fig 3.
A grade 2 labral tear showing CLJ disruption but stable CLR.
(A) Arthroscopy showing a grade 2 labral tear. (B) MR arthrography showing a contrast material-filled defect at the labrochondral junction (arrow). (L, labrum; FH, femoral head; AC, acetabular cartilage).
Fig 4.
A grade 3 labral injury in a 26-year-old woman.
(A) Simple X-ray showing a definite dysplastic acetabular structure. (B) Sagittal hip MRI showing increased intrasubstance signal intensity and a contrast material-filled paralabral cyst at the chondrolabral junction. (C, D) Arthroscopy showing an unstable labrum between the chondrolabral junction (C) and the capsulolabral recess (D), without labral displacement. (L, labrum; FH, femoral head; AC, acetabular cartilage).
Fig 5.
A grade 4 labral injury in a 45-year-old woman.
(A) Simple X-ray showing joint space narrowing. (B). Coronal MRI image showing complete lateral displacement of the labrum (arrow). The patient underwent arthroscopy combined with PAO. (C) Follow-up X-ray at postoperative 3 years. (D, E) Arthroscopy showing labral displacement was shown as a bucket-handle tear. (F) Partial resection to remove an unstable degenerative labral tear. (L, labrum; FH, femoral head; AF, acetabular fossa; AC, acetabular cartilage; JC, joint capsule).
Table 1.
Arthroscopic classification of labral tears and numbers of patients with each type.
Table 2.
Relationships between patient baseline characteristics and labral tear grade.
Table 3.
Relationships between concomitant injuries and arthroscopically determined labral tear grades.
Table 4.
Relationships of preoperative and final postoperative modified Harris hip scores with labral tear grades.
Table 5.
Relationships of preoperative and final postoperative WOMAC scores with labral tear grades.
Table 6.
Relationships between preoperative and final postoperative Tönnis OA grades and labral tear grades.
Fig 6.
Photomicrograph of a fetal hip at term (left, reprinted with permission from M. Cashin et al.: Embryology of the acetabular labral-chondral complex. J Bone Joint Surg [Br] 2008;90-B:1019–24. Copyright 2008 Springer.) (A, acetabulum; B, femoral head; C, anterior labrum; D, intra-articular projection of the anterior labrum; E, posterior labrum; F, acetabular labral transition zone). Gross specimen of a labrum (right top), resected during total hip arthroplasty from a patient with hip dysplasia, and a schematic drawing of the acetabulum including it (L, labrum; AC, acetabular cartilage).