title: Proprioception 3 years after shoulder arthroplasty in 3D motion analysis: a prospective study.
abstract: BACKGROUND
  This prospective study evaluated the development of proprioception over the course of 3 years after shoulder arthroplasty.
  
  
  METHODS
  Twenty-one patients were enrolled who underwent total shoulder arthroplasty (n = 10) or hemiarthroplasty (HEMI) (n = 11) for shoulder osteoarthritis. All patients were examined 1 day before the operation, 6 months and 3 years after surgery in a motion analysis study with an active angle-reproduction (AAR) test.
  
  
  RESULTS
  Overall proprioception measured by the AAR deteriorated significantly 3 years after surgery [from 6.6° (SD 3.1) to 10.3° (SD 5.7); p = 0.017] and was significantly worse than in the control group [10.3° (SD 5.7) vs. 7.8° (SD 2.3); p = 0.030). In the HEMI subgroup, 3 years after shoulder replacement, there is a significant deterioration of proprioception at 30° of external rotation [from 3.1° (SD 3.5) to 12.8° (SD 10.7); p = 0.031]. On average, in the TSA subgroup proprioception deteriorated from 7.1° (SD 3.1) to 8.6° (SD 1.4) and in the HEMI subgroup from 6.1° (SD 2.1) to 12.4° (SD 8.3). The comparison of postoperative impairment of proprioception between the TSA and HEMI subgroup showed significantly worse proprioception for the HEMI subgroup at 30° of external rotation [9.8° (SD 10.1) vs. 1.6° (SD 6.3) in the TSA group; p = 0.046].
  
  
  CONCLUSIONS
  In conclusion, proprioception that was measured by an AAR test remained unchanged or deteriorated 3 years after shoulder arthroplasty. The postoperative deterioration of proprioception was more distinctive in HEMI than in TSA group.
authors.affiliation: Department of Orthopedics, Trauma Surgery and Paraplegiology, University of Heidelberg, Schlierbacher Landstraße 200a, Heidelberg, Germany. michael.maier@med.uni-heidelberg.de
authors.forename: Michael W
authors.initials: MW
authors.lastname: Maier
authors.forename: Mirjam
authors.initials: M
authors.lastname: Niklasch
authors.forename: Thomas
authors.initials: T
authors.lastname: Dreher
authors.forename: Sebastian I
authors.initials: SI
authors.lastname: Wolf
authors.forename: Felix
authors.initials: F
authors.lastname: Zeifang
authors.forename: Markus
authors.initials: M
authors.lastname: Loew
authors.forename: Philip
authors.initials: P
authors.lastname: Kasten
mesh_terms: D000368:Aged; D019643:Arthroplasty, Replacement / Q000534:rehabilitation*; D016022:Case-Control Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000534:rehabilitation / Q000601:surgery*; D011434:Proprioception; D011446:Prospective Studies; D020127:Recovery of Function; D012785:Shoulder Joint / Q000503:physiopathology* / Q000601:surgery; D016896:Treatment Outcome