title: [Analysis of Fit of the Ascension® PyroCarbon PIP Total Joint Component Heads].
abstract: BACKGROUND
  The Ascension pyroCarbon proximal interphalangeal (PIP) total joint is available in 4 different sizes, and ideally, the prosthesis head will be flush with the bone. Fit of the Ascension pyrocarbon PIP joint prosthesis has not yet been investigated.
  
  
  METHODS
  The components of the Ascension pyrocarbon PIP total joint were inserted in 287 phalanges of human cadaver specimens. The distances from the edge of the component head to the edge of the bone were electronically measured radially, ulnarly, dorsally and palmarly on radiographs in posterior-anterior and lateral views.
  
  
  RESULTS
  Only one finger had a precise fit of the heads of both, the proximal and corresponding distal component in relation to the bone. Only in 17 (5 proximal, 12 distal) prosthesis components the head did the bone fit on all sides. Overall, the proximal component head tends to be too large, while the distal component head tends to be too small.
  
  
  CONCLUSIONS
  With occasional exceptions, the proximal and distal component heads of the Ascension pyrocarbon PIP total joint do not accomodate the dimensions of finger phalanges.
authors.affiliation: Klinik und Poliklinik für Orthopädie und Unfallchirurgie, Universitätsklinikum zu Köln, Köln.
authors.forename: C
authors.initials: C
authors.lastname: Ries
authors.affiliation: Klinik und Poliklinik für Orthopädie und Unfallchirurgie, Universitätsklinikum zu Köln, Köln.
authors.forename: W
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Klinik und Poliklinik für Orthopädie und Unfallchirurgie, Universitätsklinikum zu Köln, Köln.
authors.forename: L P
authors.initials: LP
authors.lastname: Müller
authors.affiliation: Abteilung für Hand-, Ästhetische und Plastische Chirurgie, Elbe Klinikum Stade, Stade.
authors.forename: B
authors.initials: B
authors.lastname: Hohendorff
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000379:methods*; D002244:Carbon; D005260:Female; D005384:Finger Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011475:Prosthesis Failure; D017755:Prosthesis Fitting; D011859:Radiography
chemical_list: C009139:pyrolytic carbon; D002244:Carbon