title: Bipolar hip arthroplasty for avascular necrosis of femoral head in young adults.
abstract: BACKGROUND
  Bipolar hip arthroplasty (BHA) is one of the options for treatment of avascular necrosis (AVN) of the femoral head. Acetabular erosion and groin pain are the most allowing for gross motion between the common complications. We propose that these complications are secondary to improper acetabular preparation allowing for motion between the BHA head and the acetabulum.
  
  
  METHODS
  The current study retrospectively evaluated patients'records from case files and also called them for clinical and radiological followup. 96 hips with AVN of the femoral head treated with BHA were included in the study. All patients were males with a mean age of 42 years (range 30-59 years). In all cases, the acetabulum was gently reamed till it became uniformly concentric to achieve tight fitting trial cup. Clinical followup using Harris hip score (HHS) and radiological study for cup migration were done at followup.
  
  
  RESULTS
  The mean followup was 7.52 years (range 4-16 years). The HHS significantly improved from a preoperative value of 39.3 (range, 54-30) to a postoperative value of 89.12 (range 74-96). According to HHS grades, the final outcome was excellent in 52 hips, good in 28 and fair in 16 hips. Hip and groin pain was reported in four hips (5%), but did not limit activity. Subsidence (less than 5 mm) of the femoral component was seen in 8 cases. Subgroup analysis showed patients with Ficat Stage 3 having better range of motion, but similar HHS as compared to Ficat Stage 4 patients.
  
  
  CONCLUSIONS
  Bipolar hip arthroplasty (BHA) using tight fitting cup and acetabular reaming in AVN hip has a low incidence of groin pain, acetabular erosion and revision in midterm followup. Good outcome and mid term survival can be achieved irrespective of the Ficat Stage.
authors.affiliation: Department of Orthopaedic, Ruby Hall Clinic, Thane, Maharashtra, India.
authors.forename: Baldev
authors.initials: B
authors.lastname: Dudani
authors.affiliation: Department of Academic Research, Sancheti Institute of Orthopaedic and Rehabilitation, Thane, Maharashtra, India ; Department of Orthopaedic, Indian Orthopaedic Research Group, Thane, Maharashtra, India.
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Shyam
authors.affiliation: Department of Academic Research, Sancheti Institute of Orthopaedic and Rehabilitation, Thane, Maharashtra, India ; Department of Orthopaedic, Indian Orthopaedic Research Group, Thane, Maharashtra, India.
authors.forename: Pankush
authors.initials: P
authors.lastname: Arora
authors.affiliation: Department of Orthopaedic, Inlaks and Budhrani Hospital, Pune, Maharashtra, India.
authors.forename: Arjun
authors.initials: A
authors.lastname: Veigus
keywords: Femoral head; Femur head; acetabular reaming; arthroplasty; avascular necrosis; avascular necrosis of bone; bipolar hip arthroplasty; femoral head prosthesis; hip