title: Lower Limbs Alignment in Patients with a Unilateral Completely Dislocated Hip.
abstract: BACKGROUND
  Severe hip osteoarthritis is known to lead to secondary osteoarthritis of the knee joint. It is not clear whether contracture or a leg length discrepancy is more important in determining the knee alignment.
  
  
  METHODS
  In this study, 48 hips in 48 patients with a unilateral completely dislocated hip (Crowe IV) were recruited. The patients were divided into two groups (Crowe IVa and IVb). The Crowe IVa group had completely dislocation with psudo-articulation, and the Crowe IVb group had completely dislocation without psudo-articulation. The lower limb alignment was divided into three patterns according to the femorotibial angle; varus (≥176 degrees), neutral(170 to 175 degrees) and valgus(≤169 degrees).
  
  
  RESULTS
  The combination of valgus alignment on the affected side and varus alignment on the unaffected side, so-called "windswept deformity" was observed in 12.5% of the patients; this included 18.2% and 7.7%, in the Crowe IVa and Crowe IVb groups, respectively. The valgus alignment on the unaffected side, namely "long leg arthropathy," was found to have occurred in 6.3% of the patients, including 13.6% of the patients in the Crowe IVa group; there were no cases of long "leg arthropathy" in the Crowe IVb group.
  
  
  CONCLUSIONS
  The lower limb alignment on the unaffected side had a tendency to be varus in the Crowe IV patients. The "windswept deformity" was observed in each of the groups; however, "long leg arthropathy" was only found in the Crowe IVa group.
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Nabeshima 5-1-1, Saga 849-8501, Japan.
authors.forename: Shinsuke
authors.initials: S
authors.lastname: Someya
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Nabeshima 5-1-1, Saga 849-8501, Japan.
authors.forename: Motoki
authors.initials: M
authors.lastname: Sonohata
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Nabeshima 5-1-1, Saga 849-8501, Japan.
authors.forename: Shuya
authors.initials: S
authors.lastname: Ide
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Nabeshima 5-1-1, Saga 849-8501, Japan.
authors.forename: Satomi
authors.initials: S
authors.lastname: Nagamine
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Nabeshima 5-1-1, Saga 849-8501, Japan.
authors.forename: Tomonori
authors.initials: T
authors.lastname: Tajima
authors.affiliation: Department of Orthopaedic Surgery, Faculty of Medicine, Saga University, Nabeshima 5-1-1, Saga 849-8501, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Mawatari
keywords: Completely dislocated hip; Contracture; Coxitis knee; Leg length discrepancy; Long leg arthropathy; Lower limb alignment; Windswept deformity