title: Monobloc radial head prostheses in complex elbow injuries: results after primary and secondary implantation.
abstract: OBJECTIVE
  Dislocations of components, loosening of the stem, overstuffing and removal in up to 24 % of common radial head prostheses (RHP) after implantation in complex elbow injuries signal the need for improvement. The latest biomechanical evidence shows advantages for monopolar designs. Clinical results after primary and secondary implantation of the newly designed press-fit monobloc monopolar RHP in cases of complex elbow injury are evaluated.
  
  
  METHODS
  Twenty-nine patients [median age 60 years (29-86)] were followed up retrospectively for a median of 25 months (7-54) post-operatively. Subjective parameters, the Mayo Elbow Performance Score (MEPS), the Broberg and Morrey score (BMS), latest radiographs and complications were evaluated.
  
  
  RESULTS
  MEPS and BMS averaged 87.2 ± 12.9 and 81.1 ± 11.9 points, respectively. No case of implant loosening was observed; the RHP had to be removed in one case (3 %). The overall complication and revision rate was higher after secondary (53 %) than after primary (19 %) implantation.
  
  
  CONCLUSIONS
  Satisfactory clinical results and low short-term removal rates emphasise the practicality of monobloc monopolar RHP. Differentiated treatment of complex elbow fracture-dislocations is compulsory to avoid the need for secondary RHP implantation which carries a higher complication rate.
authors.affiliation: Klinik für Unfall- und Wiederherstellungschirurgie, Diakoniekrankenhaus Friederikenstift gGmbH, Hanover, Germany. christoph.katthagen@ddh-gruppe.de
authors.forename: Jan Christoph
authors.initials: JC
authors.lastname: Katthagen
authors.forename: Gunnar
authors.initials: G
authors.lastname: Jensen
authors.forename: Helmut
authors.initials: H
authors.lastname: Lill
authors.forename: Christine
authors.initials: C
authors.lastname: Voigt
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D057929:Arthroplasty, Replacement, Elbow / Q000295:instrumentation / Q000379:methods*; D001696:Biomechanical Phenomena; D004551:Elbow Joint / Q000503:physiopathology / Q000601:surgery*; D058569:Elbow Prosthesis; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D004204:Joint Dislocations; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011884:Radius; D012086:Reoperation; D012189:Retrospective Studies; D016896:Treatment Outcome; D000092464:Elbow Injuries