AAHS ASPN ASRM - 2013 Annual Meeting - American Association ...

Mechanical Testing of Distal Radioulnar Instability Repair: Ligament Reconstruction vs Capsulorraphy
Institution where the work was prepared: Leonard M. Miller School of Medicine, University of Miami, Miami, FL, USA
Christopher J. Dy, BS, MD-Candidate; E. Anne Ouellette; Ali Malik; Veronica Diaz; Anna-Lena Makowski; Edward Milne; Andre Barreto; Loren Latta; Leonard M. Miller School
of Medicine, University of Miami
Introduction:
Instability of the distal radioulnar joint (DRUJ) presents a therapeutic challenge to physicians, with management varying according to the pathomechanics of
the lesion. Extensive injury to the TFCC, the major stabilizing structure of the DRUJ, is increasingly repaired via radioulnar ligament reconstruction. An alternative
procedure, a capsulorraphy, has been proposed and used by the investigative team with clinical and biomechanical success. This study is a comparison
of clinical and biomechanical stability following ligament reconstruction and capsulorraphy.
Methods:
Nine fresh-frozen cadaver arms were examined using fluoroscopy and biomechanical testing. Ulnocarpal instability was reproduced by manual division of the
dorsal and volar radioulnar ligaments, creating an ulnar-sided peripheral TFCC tear. The stability of the DRUJ was restored using the capsulorraphy in four
specimens and anatomic ligament reconstruction in five specimens. All limbs were evaluated in pre-repair and post-repair conditions. Change in radioulnar
stiffness was evaluated using the mechanical testing system.
Results:
Both repair techniques resulted in a statistically significant increase in stiffness (p0.2> 0.0="">0.0> 0.0="">0.0>
Medial-Lateral 0.3 ±="" 0.0 ±="" 0.0 ±=""
0.8="">0.3> 0.0="">0.0> 0.0="">0.0>
Proximal-Distal 0.3 ±="" 0.2 ±="" 0.2 ±=""
0.8="">0.3> 0.4="">0.2> 0.4="">0.2>
* significantly more angulation-rotation, p < 0.05
Conclusion:
In our cadaveric model, short arm casting was just as effective as thumb spica casting to prevent angulation of scaphoid fractures in the presence of thumb
extension and flexion.
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