title: Impact of scapular notching on clinical outcomes after reverse total shoulder arthroplasty: an analysis of 476 shoulders.
abstract: BACKGROUND
  Scapular notching is a complication unique to reverse total shoulder arthroplasty (rTSA), although its clinical implications are unclear and remains controversial.
  
  
  METHODS
  We retrospectively reviewed rTSA patients of a single implant design in 476 shoulders with a minimum 2-year clinical and radiographic follow-up. Clinical measures included active range of motion and American Shoulder and Elbow Surgeons scores, in addition to one or more of the Constant score, Shoulder Pain and Disability Index, Simple Shoulder Test (SST), and University of California, Los Angeles Shoulder Rating Scale. Complications and rates of humeral radiolucencies were also recorded.
  
  
  RESULTS
  Scapular notching was observed in 10.1% (48 of 476) of rTSAs and was associated with a longer clinical follow-up, lower body weight, lower body mass index, and when the operative side was the nondominant extremity. Patients with scapular notching had significantly lower postoperative scores on the Shoulder Pain and Disability Index, Constant, Simple Shoulder Test, and University of California, Los Angeles, Shoulder Rating Scale compared with patients without scapular notching. Patients with scapular notching also had significantly lower active abduction, significantly less strength, and trended toward significantly less active forward flexion (P = .0527). Finally, patients with scapular notching had a significantly higher complication rate and trended toward a significantly higher rate of humeral radiolucent lines (P = .0896) than patients without scapular notching.
  
  
  CONCLUSIONS
  This large-scale outcome study demonstrates that patients with scapular notching have significantly poorer clinical outcomes, significantly less strength and active range of motion, and a significantly higher complication rate than patients without scapular notching. Longer-term follow-up is necessary to confirm that these statistical observations in the short-term will result in greater clinically meaningful differences over time.
authors.affiliation: Department of Orthopaedic Surgery, Hospital for Joint Diseases, New York University, Langone Medical Center, New York, NY, USA.
authors.forename: Brent
authors.initials: B
authors.lastname: Mollon
authors.affiliation: Department of Orthopaedic Surgery, Hospital for Joint Diseases, New York University, Langone Medical Center, New York, NY, USA.
authors.forename: Siddharth A
authors.initials: SA
authors.lastname: Mahure
authors.affiliation: Exactech, Inc., Gainesville, FL, USA.
authors.forename: Christopher P
authors.initials: CP
authors.lastname: Roche
authors.affiliation: Department of Orthopaedic Surgery, Hospital for Joint Diseases, New York University, Langone Medical Center, New York, NY, USA. Electronic address: joseph.zuckerman@nyumc.org.
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Zuckerman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000072228:Arthroplasty, Replacement, Shoulder / Q000009:adverse effects* / Q000379:methods; D015992:Body Mass Index; D001835:Body Weight; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D053580:Muscle Strength; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology*; D011859:Radiography; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D012540:Scapula / Q000000981:diagnostic imaging / Q000293:injuries*; D012785:Shoulder Joint / Q000503:physiopathology; D020069:Shoulder Pain / Q000209:etiology; D016896:Treatment Outcome
keywords: Scapular notching; arthroplasty; clinical outcomes; complications; rTSA; retrospective