gms | German Medical Science

58. Kongress der Deutschen Gesellschaft für Handchirurgie

Deutsche Gesellschaft für Handchirurgie

12. - 14.10.2017, München

Patient-specific scaphoid replacement out of the 3D-printer – Idea and first pre-clinical results

Meeting Abstract

  • corresponding author presenting/speaker Philipp Honigmann - Kantonsspital Baselland, Handchirurgie, Liestal, Switzerland
  • Ralf Schumacher - Fachhoschule Nordwestschweiz, Hochschule für Life Sciences, Muttenz, Switzerland
  • Johannes Homa - Lithoz GmbH, Wien, Austria
  • Romy Marek - Fachhoschule Nordwestschweiz, Hochschule für Life Sciences, Muttenz, Switzerland
  • Franz Büttner - Kantonsspital Baselland, Radiologie, Liestal, Switzerland
  • Florian Thieringer - Universitätsspital Basel, Klinik für Mund-, Kiefer- und Gesichtschirurgie, Basel, Switzerland
  • Mathias Häfeli - Kantonsspital Baden, Handchirurgie, Baden, Switzerland

Deutsche Gesellschaft für Handchirurgie. 58. Kongress der Deutschen Gesellschaft für Handchirurgie. München, 12.-14.10.2017. Düsseldorf: German Medical Science GMS Publishing House; 2017. Doc17dgh059

doi: 10.3205/17dgh059, urn:nbn:de:0183-17dgh0596

Veröffentlicht: 10. Oktober 2017

© 2017 Honigmann et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objectives: In cases of non-preservable or -reconstructable scaphoid bone as after multifragmentary fracture, avascular necrosis or failed reconstruction after pseudoarthrosis, the treatment options are limited to partial wrist fusion ,proximal row carpectomy (PRC) or implantation of a place holder made of metal or pyrocarbon. All these options alter wrist biomechanics significantly and lead to reduced grip strength and mobility. Whereas arthrodesis exhibits the risk of non-union, radio-capitate degeneration may result in PRC over time. Used prosthesis act as place holders and do not prevent carpal collapse and are at risk to dislocate.

Methods: We hypothesized that a combination of a near anatomic scaphoid replacement with ligament suspension might overcome some of the disadvantages of current treatment options. We present a patient-specific scaphoid replacement with FCR-suspension to reconstruct the scapho-trapezial and scapho-lunate (SL) ligaments.

Based on CT generated DICOM-data a prosthesis of the scaphoid is 3D-printed. The original scaphoid is removed and replaced by the prosthesis. One distally based half of the FCR is harvested and pulled through a tunnel along the longitudinal axis of the prosthesis from distal-palmar to proximal-dorsal. It is then brought back to the palmar side through a sagittal drill hole in the lunate before it is sutured back to its origin. This suspends the prosthesis and reconstructs the dorsal and palmar aspects of the SL-ligament as well as the palmar scapho-trapezial ligaments.

Results: In a first series with two cadaver wrists one prosthesis made of titanium and one made of ceramics were implanted this way. We then took CT-scans of the wrist mounted on plastic splints in five predefined positions (neutral, max. flexion, extension, radial- and ulnar duction) to evaluate scaphoid-excursions. We also evaluated scaphoid-mobility under fluoroscopy to get an idea of the movements. Pre- and postoperative CT-scans and fluoroscopy were compared with each other. We found that the scaphoid prosthesis moved quite similar to the original scaphoid indicating that the suspension might help the prosthesis to move in a natural way and possibly prevent carpal collapse. Multi-cyclic testing with more specimens will be necessary to draw more reliable conclusions about these encouraging first results.

Conclusion: Patient specific scaphoid replacement could become an alternative treatment option in complex and non-salvageble scaphoid-pathologies.