title: Clinical and radiologic outcomes of pyrocarbon radial head prosthesis: midterm results.
abstract: BACKGROUND
  The modular pyrocarbon (MoPyC) radial head prosthesis (Tornier, Saint-Ismier, France) is a monoblock modular radial head prosthesis. This study assessed midterm outcomes after implantation of the prosthesis.
  
  
  METHODS
  A retrospective study was conducted of a consecutive cohort of 65 patients who underwent radial head replacement with the MoPyC prosthesis from January 2006 to April 2013. Indications were fractures, early or late failures from orthopedic or fixation treatments, and revisions after another implant. Patients were observed for >2 years for range of motion, pain, and stability; function by the Mayo Elbow Performance Score (total score, 100) and grip strength were assessed. Quality of stem implantation, bone resorption around the neck, and periprosthetic lucency were noted and quantified on radiographs. Capitellum shape and density as well as humeroulnar aspect (river delta sign) were evaluated. Complications and revision procedures were noted.
  
  
  RESULTS
  We evaluated 52 of 65 patients (mean follow-up, 46 ± 20 months; range, 24-108). The Mayo Elbow Performance Score was 96 ± 7; pain score, 42 ± 7/45; and motion score, 18 ± 2/20. Function and stability were excellent. Radiology revealed 92% of patients with cortical resorption around the neck without mechanical failure. Bone resorption was mostly anterior and lateral; it resolved within the first year and thereafter was stable. Eight patients underwent revision surgery for stiffness. No implant failures were noted.
  
  
  CONCLUSIONS
  Results of the MoPyC radial head prosthesis appear to be satisfactory. Bone resorption around the neck (stress shielding) is frequent and stable after 1 year and does not impair stem fixation. The MoPyC prosthesis appears to be a reliable solution for replacing the radial head.
authors.affiliation: Department of Orthopaedics and Sports Traumatology, Hôpital de l'Archet 2, Université de Nice-Sophia-Antipolis (UNSA), Nice, France.
authors.forename: Marc-Olivier
authors.initials: MO
authors.lastname: Gauci
authors.affiliation: Department of Orthopaedics, Clinique Saint Jean, Cagnes-sur-Mer, France. Electronic address: mnx.winter@gmail.com.
authors.forename: Matthias
authors.initials: M
authors.lastname: Winter
authors.affiliation: Department of Reconstructive and Hand Surgery, Hôpital Saint Roch, Université de Nice-Sophia-Antipolis (UNSA), Nice, France.
authors.forename: Christian
authors.initials: C
authors.lastname: Dumontier
authors.affiliation: Department of Orthopaedics and Sports Traumatology, Hôpital de l'Archet 2, Université de Nice-Sophia-Antipolis (UNSA), Nice, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Bronsard
authors.affiliation: Department of Hand Surgery, Clinique Clémentville, Montpellier, France.
authors.forename: Yves
authors.initials: Y
authors.lastname: Allieu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000009:adverse effects; D001862:Bone Resorption / Q000000981:diagnostic imaging; D002244:Carbon; D004551:Elbow Joint / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D058569:Elbow Prosthesis / Q000009:adverse effects; D005260:Female; D018737:Hand Strength; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D011884:Radius / Q000601:surgery*; D016059:Range of Motion, Articular; D012086:Reoperation; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: C009139:pyrolytic carbon; D002244:Carbon
keywords: Elbow prosthesis; elbow dislocation; osteolysis; pyrocarbon implant; radial head fractures