title: Rotational fluoroscopy assists in detection of intra-articular screw penetration during volar plating of the distal radius.
abstract: OBJECTIVE
  Intra-articular screw penetration is one complication of volar plate fixation of distal radius fractures. This study was designed to determine the most commonly used imaging techniques and views during volar plating of distal radius fractures and to evaluate surgeons' ability to detect intra-articular screw placement on static fluoroscopic images and rotational fluoroscopy.
  
  
  METHODS
  Active members of the American Society for Surgery of the Hand were polled regarding preferred imaging techniques (fluoroscopic vs cassette radiographs) and views (rotational fluoroscopy or static orthogonal/anatomic tilt/semipronated imaging) during volar plating of distal radius fractures. After the survey, volar locking plates were applied to 30 cadaveric distal radiuses. We intentionally penetrated a single screw into the radiocarpal joint in half of the specimens (15 arms) and intentionally did not penetrate the radiocarpal joint in the other half. Imaging (standard posteroanterior [PA] and lateral views, 11 degrees tilt PA and 22 degrees tilt lateral views, and two 360 degrees fluoroscopy movies) was performed using a custom jig. Five surgeons blinded to results reviewed randomized image sets evaluating for intra-articular screw placement. Receiver operating characteristic curves were constructed to compare the reliability of each fluoroscopic projection or movie.
  
  
  RESULTS
  Among 696 survey respondents, 606 exclusively used fluoroscopic imaging (without cassette radiographs) and over 450 preferred either tilt images or rotational fluoroscopy to detect intra-articular screw penetration. In our cadaveric model, rotational fluoroscopy provided the highest sensitivity (93%) and specificity (96%) for the detection of intra-articular screw penetration. Rotational fluoroscopy was significantly more reliable (p<.01) than most images (standard lateral, 11 degrees PA, 22 degrees lateral, paired PA/lateral) and trended strongly toward better reliability for all remaining images (standard PA [p=.07], paired 11 degrees PA/22 degrees lateral [p=.08], and 22 degrees tilt fluoroscopy movie [p=.11]).
  
  
  CONCLUSIONS
  Rotational fluoroscopy improves the surgeon's ability to detect intra-articular screw penetration during volar plating of the distal radius. No combination of imaging allowed detection of all intra-articular screws. A high level of suspicion for intra-articular screw penetration should be maintained during volar plating of distal radial fractures.
authors.affiliation: Department of Orthopaedic Surgery, University of Cincinnati College of Medicine, Cincinnati, OH, USA.
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Tweet
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Calfee
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Stern
mesh_terms: D001860:Bone Plates; D001863:Bone Screws / Q000009:adverse effects*; D002102:Cadaver; D016009:Chi-Square Distribution; D005471:Fluoroscopy / Q000379:methods*; D006801:Humans; D007431:Intraoperative Complications / Q000000981:diagnostic imaging*; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data; D012372:ROC Curve; D015641:Radiography, Interventional / Q000379:methods*; D011885:Radius Fractures / Q000000981:diagnostic imaging / Q000601:surgery*; D011795:Surveys and Questionnaires