J Wrist Surg 2015; 04 - A032
DOI: 10.1055/s-0035-1567924

Evaluation of Radiographic Alignment, Function and Complications of a New Variable-Angle Locking Volar Distal Radius Plate—A Prospective Multicenter Case Series

Teun Teunis MD1, Alexander Joeris MD2, Daniel Rikli MD3, Jesse Jupiter MD1
  • 1Orthopaedic Hand and Upper Extremity Service, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
  • 2AO Clinical Investigation and Documentation, Davos, Switzerland
  • 3Traumatologie und Unfallchirurgie, Universitaetsspital Basel, Basel, Switzerland

Background: Volar locking plates help to obtain anatomic reduction with stable fixation in distal radius fractures. To evaluate the performance of a new variable-angle locking volar distal radius plate (VA LCP), we assessed change in alignment 1 year after surgery. Secondary aims include (1) comparing single versus double distal screw rows; (2) assessing functional outcomes and adverse events; and (3) comparing gap and step-off measured on radiographs and computed tomography (CT) scans.

Methods: The study cohort comprised 73 patients with a mean age of 61 years (range 25–88 years). Sixty-six patients (90%) were available at 1 year. We obtained fracture radiographs and CT scans pre- and postoperatively and at 12 months. Radial height, ulnarward inclination, ulnar variance, palmar tilt, gap and step-off, scapholunate angle, teardrop angle, and anteroposterior distance were measured. At the same time we determined grip strength, wrist range of motion, disability, and quality of life.

Results: The largest change on radiographs (> 1°) was seen in scapholunate angle (n = 43, 66%) and teardrop angle (n = 34, 52%). Other measurements were relatively stable; only one patient (1.5%) had >3° loss of palmar tilt or > 3-mm increase in lateral gap. On computed tomography scans only four patients had > 3-mm change in alignment. There was no difference between one and two distal screw rows. Gap measured on posteroanterior radiographs and frontal CT scans correlated best (r = 0.33, p < 0.001). Range of motion increased to 90% and grip strength to 87% of the opposite side. Disproportionate pain and disability (i.e., complex regional pain syndrome) was the most common complication (n = 6).

Conclusions Other than in scapholunate and teardrop angles, we found only limited change in radiological measures 1 year after volar plate fixation. Our new VA LCP seems to offer stable alignment, good function, and limited complications. Future studies could assess the effect of loss of reduction on function and quality of life.

Level of Evidence Therapeutic level IV.

Keywords

Distal radius - Fractures - Volar locking plate - Alignment