title: Clinical and Radiographic Outcomes of the Simpliciti Canal-Sparing Shoulder Arthroplasty System: A Prospective Two-Year Multicenter Study.
abstract: BACKGROUND
  Stemmed humeral components have been used since the 1950s; canal-sparing (also known as stemless) humeral components became commercially available in Europe in 2004. The Simpliciti total shoulder system (Wright Medical, formerly Tornier) is a press-fit, porous-coated, canal-sparing humeral implant that relies on metaphyseal fixation only. This prospective, single-arm, multicenter study was performed to evaluate the two-year clinical and radiographic results of the Simpliciti prosthesis in the U.S.
  
  
  METHODS
  One hundred and fifty-seven patients with glenohumeral arthritis were enrolled at fourteen U.S. sites between July 2011 and November 2012 in a U.S. Food and Drug Administration (FDA) Investigational Device Exemption (IDE)-approved protocol. Their range of motion, strength, pain level, Constant score, Simple Shoulder Test (SST) score, and American Shoulder and Elbow Surgeons (ASES) score were compared between the preoperative and two-year postoperative evaluations. Statistical analyses were performed with the Student t test with 95% confidence intervals. Radiographic evaluation was performed at two weeks and one and two years postoperatively.
  
  
  RESULTS
  One hundred and forty-nine of the 157 patients were followed for a minimum of two years. The mean age and sex-adjusted Constant, SST, and ASES scores improved from 56% preoperatively to 104% at two years (p < 0.0001), from 4 points preoperatively to 11 points at two years (p < 0.0001), and from 38 points preoperatively to 92 points at two years (p < 0.0001), respectively. The mean forward elevation improved from 103° ± 27° to 147° ± 24° (p < 0.0001) and the mean external rotation, from 31° ± 20° to 56° ± 15° (p < 0.0001). The mean strength in elevation, as recorded with a dynamometer, improved from 12.5 to 15.7 lb (5.7 to 7.1 kg) (p < 0.0001), and the mean pain level, as measured with a visual analog scale, decreased from 5.9 to 0.5 (p < 0.0001). There were three postoperative complications that resulted in revision surgery: infection, glenoid component loosening, and failure of a subscapularis repair. There was no evidence of migration, subsidence, osteolysis, or loosening of the humeral components or surviving glenoid components.
  
  
  CONCLUSIONS
  The study demonstrated good results at a minimum of two years following use of the Simpliciti canal-sparing humeral component. Clinical results including the range of motion and the Constant, SST, and ASES scores improved significantly, and radiographic analysis showed no signs of loosening, osteolysis, or subsidence of the humeral components or surviving glenoid components.
  
  
  METHODS
  Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
authors.affiliation: Aurora Medical Center-Grafton, Grafton, Wisconsin Sean.churchill@aurora.org.
authors.forename: R Sean
authors.initials: RS
authors.lastname: Churchill
authors.affiliation: Great Lakes Orthopaedic Center, Traverse City, Michigan.
authors.forename: Christopher
authors.initials: C
authors.lastname: Chuinard
authors.affiliation: Beaumont Health, Royal Oak, Michigan.
authors.forename: J Michael
authors.initials: JM
authors.lastname: Wiater
authors.affiliation: Department of Orthopaedics, Medical University of South Carolina, Charleston, South Carolina.
authors.forename: Richard
authors.initials: R
authors.lastname: Friedman
authors.affiliation: Sports and Orthopaedic Specialists, Edina, Minnesota.
authors.forename: Michael
authors.initials: M
authors.lastname: Freehill
authors.affiliation: Ortho & Neuro Center of the Cascades, Bend, Oregon.
authors.forename: Scott
authors.initials: S
authors.lastname: Jacobson
authors.affiliation: Knoxville Orthopaedic Clinic, Knoxville, Tennessee.
authors.forename: Edwin
authors.initials: E
authors.lastname: Spencer
authors.affiliation: Knoxville Orthopaedic Clinic, Knoxville, Tennessee.
authors.forename: G Brian
authors.initials: GB
authors.lastname: Holloway
authors.affiliation: Clinical Research Division, Bassett Healthcare Network Research Institute, Cooperstown, New York.
authors.forename: Jocelyn
authors.initials: J
authors.lastname: Wittstein
authors.affiliation: Clinical Research Division, Bassett Healthcare Network Research Institute, Cooperstown, New York.
authors.forename: Tally
authors.initials: T
authors.lastname: Lassiter
authors.affiliation: Missouri Orthopaedic Institute, Columbia, Missouri.
authors.forename: Matthew
authors.initials: M
authors.lastname: Smith
authors.affiliation: Department of Orthopaedics and Rehabilitation, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Theodore
authors.initials: T
authors.lastname: Blaine
authors.affiliation: Midwest Orthopedics at Rush, Rush University Medical Center, Chicago, Illinois.
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Nicholson
mesh_terms: D000328:Adult; D000368:Aged; D001168:Arthritis / Q000000981:diagnostic imaging / Q000601:surgery*; D019643:Arthroplasty, Replacement / Q000295:instrumentation* / Q000379:methods; D005260:Female; D006801:Humans; D007595:Joint Prosthesis; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography; D016059:Range of Motion, Articular; D012785:Shoulder Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D013223:Statistics as Topic; D016896:Treatment Outcome