Michael Hackl1, Kilian Wegmann2, Christian Ries2, Tim Leschinger2, Klaus Josef Burkhart3, Lars Peter Müller2. 1. Center for Orthopedic and Trauma Surgery, University Medical Center, Cologne, Germany. Electronic address: michael.hackl@uk-koeln.de. 2. Center for Orthopedic and Trauma Surgery, University Medical Center, Cologne, Germany. 3. Clinic for Shoulder Surgery, Bad Neustadt/Saale, Germany.
Abstract
PURPOSE: To evaluate radiographic signs of posterolateral rotatory instability (PLRI) on magnetic resonance imaging (MRI). The goal was to establish objective radiographic criteria to aid in the diagnosis of PLRI. METHODS: The MRI scans of 60 patients were evaluated retrospectively. Two study groups were compared. Group 1 (n = 30) consisted of unstable elbows in which PLRI was confirmed by clinical examination and arthroscopy. Group 2 (stable; n = 30) served as the control group. Patients in group 2 had transient epicondylitis without clinical suspicion of instability. Joint incongruity was analyzed for sagittal views through the radial head and the coronoid tip and for coronal and axial views. Interobserver and intra-observer reliability were evaluated. RESULTS: In the sagittal view through the radial head, average radiocapitellar incongruity differed significantly between groups 1 and 2. In addition, mean ulnohumeral incongruity in an axial view through the motion axis of the distal humerus showed significant differences between groups. Sagittal views through the tip of the coronoid and coronal views did not reveal significant differences in patients with unstable elbows compared with the control group. CONCLUSIONS: The current study provides useful MRI criteria indicative of PLRI when combined with physical examination. Cutoff points of 1.2 mm for radiocapitellar incongruity (sagittal view) and 0.7 mm for axial ulnohumeral incongruity (axial view) are suitable to screen for PLRI. Radiocapitellar incongruity greater than 2 mm and axial ulnohumeral incongruity greater than 1 mm are highly suspicious of elbow instability. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.
PURPOSE: To evaluate radiographic signs of posterolateral rotatory instability (PLRI) on magnetic resonance imaging (MRI). The goal was to establish objective radiographic criteria to aid in the diagnosis of PLRI. METHODS: The MRI scans of 60 patients were evaluated retrospectively. Two study groups were compared. Group 1 (n = 30) consisted of unstable elbows in which PLRI was confirmed by clinical examination and arthroscopy. Group 2 (stable; n = 30) served as the control group. Patients in group 2 had transient epicondylitis without clinical suspicion of instability. Joint incongruity was analyzed for sagittal views through the radial head and the coronoid tip and for coronal and axial views. Interobserver and intra-observer reliability were evaluated. RESULTS: In the sagittal view through the radial head, average radiocapitellar incongruity differed significantly between groups 1 and 2. In addition, mean ulnohumeral incongruity in an axial view through the motion axis of the distal humerus showed significant differences between groups. Sagittal views through the tip of the coronoid and coronal views did not reveal significant differences in patients with unstable elbows compared with the control group. CONCLUSIONS: The current study provides useful MRI criteria indicative of PLRI when combined with physical examination. Cutoff points of 1.2 mm for radiocapitellar incongruity (sagittal view) and 0.7 mm for axial ulnohumeral incongruity (axial view) are suitable to screen for PLRI. Radiocapitellar incongruity greater than 2 mm and axial ulnohumeral incongruity greater than 1 mm are highly suspicious of elbow instability. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic IV.
Authors: Hyoung Seok Jung; Jae Sung Lee; In Hyeok Rhyou; Ho Won Lee; Min Jong Park Journal: Knee Surg Sports Traumatol Arthrosc Date: 2019-05-07 Impact factor: 4.342
Authors: Kay Schmidt-Horlohé; Alexander Klug; Manuel Weißenberger; Den Nis Wincheringer; Reinhard Hoffmann Journal: Orthopade Date: 2018-08 Impact factor: 1.087