title: Radiographic evaluation of early periprosthetic femoral bone contrast and prosthetic stem alignment after uncemented and cemented total hip replacement in dogs.
abstract: OBJECTIVE
  To radiographically evaluate periprosthetic femoral bone contrast and assess alignment of the prosthetic stem after uncemented and cemented total hip replacement (THR).
  
  
  METHODS
  Prospective clinical study.
  
  
  METHODS
  Dogs (n = 15).
  
  
  METHODS
  Dogs were classified into uncemented (n = 8) and cemented (n = 7) THR groups. Radiographs were analyzed using image processing software to evaluate femoral bone contrast (gray scale value, GV) for each and combined modified Gruen zone(s) immediately and 4 months after THR. Modified Gruen zones were classified into 5 zones to analyze retrospectively the regional radiographic GV of the femur around uncemented and cemented prosthetic stem. Alignment of prosthetic stem was assessed immediately and 4 months postoperatively. Variables were compared by use of 2-tailed t-test, with P < .05 considered significant.
  
  
  RESULTS
  Zone 1 showed significant decrease in the mean bone GV 4 months after uncemented THR. No differences in zones 1-5 after 4 months of cemented THR. Combined zones showed significant decrease in overall mean bone GV 4 months after uncemented THR. No changes were observed 4 months after cemented THR. Number of limbs with varus-aligned femoral stem markedly increased after 4 months of uncemented THR.
  
  
  CONCLUSIONS
  Regional bone contrast and prosthetic stem alignment vary with the design of THR.
authors.affiliation: Department of Surgery, Faculty of Veterinary Medicine, Cairo University, Giza, Egypt.
authors.forename: Ayman A
authors.initials: AA
authors.lastname: Mostafa
authors.forename: Svenja
authors.initials: S
authors.lastname: Drüen
authors.forename: Ingo
authors.initials: I
authors.lastname: Nolte
authors.forename: Patrick
authors.initials: P
authors.lastname: Wefstaedt
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D019644:Arthroplasty, Replacement, Hip / Q000662:veterinary*; D001843:Bone Cements; D015519:Bone Density / Q000502:physiology; D004285:Dogs; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging*; D006622:Hip Prosthesis / Q000662:veterinary*; D008297:Male; D011859:Radiography
chemical_list: D001843:Bone Cements