title: The Artelon CMC spacer compared with tendon interposition arthroplasty.
abstract: OBJECTIVE
  The Artelon CMC spacer is designed for surgical treatment of osteoarthritis (OA) in the carpometacarpal joint of the thumb (CMC-I). Good results using this degradable device were previously presented in a pilot study. We now present results from a larger randomized, controlled, multicenter study.
  
  
  METHODS
  109 patients (94 females) with a mean age of 60 (42-83) years, suffering from painful CMC OA, were included in the study at 7 centers in Sweden. The patients were randomized to Artelon CMC spacer (test, n = 72) or tendon arthroplasty (control, n = 37) at a ratio of 2:1. Perceived pain was recorded on a visual analog scale (VAS) before treatment and after 3, 6, and 12 months, when measuring maximal tripod pinch strength (primary outcome measure). In addition, range of motion, radiographic findings, and functional testing were recorded pre- and postoperatively.
  
  
  RESULTS
  Swelling and pain were more common in the test group and 6 implants were removed because of such symptoms. 5 of these patients did not receive antibiotics preoperatively according to the study protocol. In a per-protocol analysis, i.e. patients without signs of concomitant OA in the scaphoid-trapezium-trapezoid (STT) joint and those in the test group who received antibiotics, the mean difference in tripod pinch strength increase, adjusted for baseline, was 1.4 kg in favor of the test group (not statistically significant). Statistically significant pain relief was achieved in both groups, with perceived pain gradually decreasing during the follow-up period. In the intention-to-treat analysis but not in the per-protocol analysis, significantly better pain relief (VAS) was obtained in the control group. Patient-perceived disability evaluated by the DASH questionnaire improved in both groups.
  
  
  CONCLUSIONS
  The Artelon CMC spacer did not show superior results compared to tendon interposition arthroplasty. Proper use of preoperative antibiotics and a thorough patient selection appear to be important for the results.
authors.affiliation: Department of Hand Surgery, Sahlgrenska University Hospital, Göteborg. anders.g.nilsson@vgregion.se
authors.forename: Anders
authors.initials: A
authors.lastname: Nilsson
authors.forename: Monica
authors.initials: M
authors.lastname: Wiig
authors.forename: Håkan
authors.initials: H
authors.lastname: Alnehill
authors.forename: Magnus
authors.initials: M
authors.lastname: Berggren
authors.forename: Sten
authors.initials: S
authors.lastname: Björnum
authors.forename: Mats
authors.initials: M
authors.lastname: Geijer
authors.forename: Philippe
authors.initials: P
authors.lastname: Kopylov
authors.forename: Christer
authors.initials: C
authors.lastname: Sollerman
mesh_terms: D020341:Absorbable Implants; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001178:Arthroplasty / Q000009:adverse effects / Q000379:methods; D052737:Carpometacarpal Joints / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007595:Joint Prosthesis; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000601:surgery*; D010147:Pain Measurement; D016059:Range of Motion, Articular; D011795:Surveys and Questionnaires; D013710:Tendons / Q000601:surgery*; D016896:Treatment Outcome