title: [APPLICATION AND EFFECTIVENESS OF BIOLOGICAL TYPE ACETABULAR CUP IN ADULT Crowe TYPE IV DEVELOPMENTAL DYSPLASIA OF THE HIP].
abstract: OBJECTIVE
  To investigate the application and effectiveness of the biological type acetabular cup(diameter < 44 mm) in adult Crowe type IV developmental dysplasia of the hip (DDH).
  
  
  METHODS
  Between April 2001 andAugust 2013, biological type acetabular cup was used in total hip arthroplasty for the treatment of Crowe type IV DDH in16 cases (20 hips). There were 3 males and 13 females, aged 31-69 years (mean, 49 years). Unilateral hip was involved in 12cases, and bilateral hips in 4 cases. The patients showed pain of the hip joint and inequality of lower limb (shortening ofaffected limb 1.8-6.0 cm in length, 3.5 cm on average). Acetabular deformity, the relationship and the severity of femoralhead dislocation were comfirmed on the X-ray films. The preoperative Harris score was 34.0 ± 6.9.
  
  
  RESULTS
  All patientsachieved healing of incision by first intention, with no complication of infection or neurovascular injury. Sixteen caseswere followed up 4-12 years (mean, 7.5 years). At 2 weeks after operation, dislocation occurred in 2 cases, and were fixedwith plaster for 3 weeks after reduction of the hip. Postoperative X-ray films showed complete reduction of femoral head;the average acetabular coverage of the cup of the weight-bearing area was 98.5% (range, 98.2%-99.1%). The cup from theRanawat triangle was 4.6-7.0 mm (mean, 5.8 mm) in medial shifting, and was 4.5-7.9 mm (mean, 6.2 mm) in elevation,it located at cup lateral surface area inside the iliopectineal line and the Kohler line (< 40%); the cup abduction angle was(45 ± 5)degrees, and the anteversion angle was (10 ± 5)degrees. The other patients had no prosthesis loosening except 1 patient havingextensive acetabular prosthesis loosening because of acetabular osteolysis at 12 years after operation. The hip Harris scorewas significantly improved to 85.0 ± 7.5 at 1 year after operation (t = 14.34, P = 0.01).
  
  
  CONCLUSIONS
  The acetabular grindingprocess to retain enough bone combined with a small cup of-biological prosthesis treating adult Crowe type IV DDH has theadvantages of satisfactory coverage and initial acetabular fixation, so good early and mid-term effectiveness can be obtained.
authors.forename: Ning
authors.initials: N
authors.lastname: Xu
authors.forename: Junying
authors.initials: J
authors.lastname: Sun
authors.forename: Xijiang
authors.initials: X
authors.lastname: Zhao
authors.forename: Tao
authors.initials: T
authors.lastname: Wang
mesh_terms: D000077:Acetabulum / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000601:surgery*; D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip; D001847:Bone Diseases; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery; D005270:Femur Head; D005500:Follow-Up Studies; D006618:Hip Dislocation, Congenital / Q000000981:diagnostic imaging / Q000601:surgery*; D006621:Hip Joint; D006622:Hip Prosthesis; D006801:Humans; D004204:Joint Dislocations; D007870:Leg Length Inequality / Q000503:physiopathology / Q000601:surgery*; D035002:Lower Extremity; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011475:Prosthesis Failure; D011859:Radiography; D020127:Recovery of Function; D016896:Treatment Outcome