The Effect of Plate Design on the Flexor Pollicis Longus Tendon After Volar Locked Plating of Distal Radial Fractures

Abstract

Update This article was updated on October 7, 2019, because of a previous error. On page 1586, in the Abstract section entitled “Conclusions,” the sentence that had read “We found that the FPL volar locking plate and decreased volar tilt significantly reduced the plate-tendon contact area compared with the standard volar locking plate.” now reads “We found that the FPL volar locking plate and increased volar tilt significantly reduced the plate-tendon contact area compared with the standard volar locking plate.” An erratum has been published: J Bone Joint Surg Am. 2019 Nov 6;101(21):e119. Background: Injury to and rupture of the flexor pollicis longus (FPL) tendon are known complications after volar locking plate fixation for distal radial fractures. Recent investigations have demonstrated that plate positioning contributes to the risk of tendon rupture; however, the impact of plate design has yet to be established. The purpose of this study was to compare FPL tendon-to-plate distance, FPL tendon-plate contact, and sonographic changes in the FPL tendon for 2 volar locking plate designs (ADAPTIVE compared with FPL) using ultrasound examination. Methods: We identified patients who underwent distal radial fracture fixation by 2 fellowship-trained hand surgeons with either standard (ADAPTIVE) or FPL plates. Patients were matched by age, sex, and Soong grade. Enrolled patients returned for a research-related office visit for a clinical examination and bilateral wrist ultrasound. We measured plate-tendon distance, plate-tendon contact, sonographic changes in the FPL tendon, and postoperative radiographic parameters in the operatively treated wrist and the uninjured wrist. Results: Forty patients with Soong grade-1 or 2 plate prominence underwent bilateral wrist ultrasound examination; all of the patients had distal radial fracture fixation, 20 with the standard volar locking plate and 20 with the FPL volar locking plate. Similar proportions of patients with the FPL plate (65%) and those with the standard plate (79%) had plate-tendon contact (p = 0.48); however, the FPL volar locking plate group had significantly less of the FPL tendon in contact with the volar plate than the standard volar locking plate group at wrist extension at both 0° (p < 0.001) and 45° (p < 0.001). There was no difference (p = 0.5) in the proportion of patients with sonographic changes in the FPL tendon between the FPL volar locking plate group (25%) and the standard volar locking plate group (21%). The postoperative volar tilt was significantly lower in patients with FPL plate-tendon contact (p = 0.01) and correlated moderately with the percentage of FPL tendon-plate contact at 0° (r = −0.51; p < 0.001) and 45° (r = −0.53; p < 0.001). There were no cases of tendon rupture in the cohort. Conclusions: We found that the FPL volar locking plate and increased volar tilt significantly reduced the plate-tendon contact area compared with the standard volar locking plate. In our asymptomatic cohort, we were unable to find a difference in sonographic changes in the FPL tendon. Further studies are needed to determine the clinical importance of decreased tendon-plate contact area seen in modified volar locking plate designs. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of Levels of Evidence.

Complications after operatively treated distal radius fractures

“…Analogously, Stepan et al could show that by using such plates the contact area between the plate and the FPL tendon can be significantly reduced. However, the ultrasound examination detected no changes in the tendon between FPL and normal volar plating [85]. To date no long-term results are available to make definitive statements on a positive effect of the FPL plate regarding flexor tendon irritation or rupture.…”

Analysis of risk factors associated with flexor pollicis longus injury after volar plating of distal radius fractures

“…Fracture malreduction as a generally known risk factor for FPL rupture. 2 , 25–28 Orbay and Touhami 2 reported that flexor tendon problems can occur if fracture reduction is lost. Stepan et al.…”

“…Stepan et al. 25 found that postoperative volar tilt significantly reduced the likelihood and amount of FPL tendon–plate contact on ultrasound examination. Wurtzel et al.…”

“…Fracture malreduction as a generally known risk factor for FPL rupture. 2,[25][26][27][28] Orbay and Touhami 2 reported that flexor tendon problems can occur if fracture reduction is lost. Stepan et al 25 found that postoperative volar tilt significantly reduced the likelihood and amount of FPL tendon-plate contact on ultrasound examination.…”

“…2,[25][26][27][28] Orbay and Touhami 2 reported that flexor tendon problems can occur if fracture reduction is lost. Stepan et al 25 found that postoperative volar tilt significantly reduced the likelihood and amount of FPL tendon-plate contact on ultrasound examination. Wurtzel et al 28 also demonstrated that the volar tilt was a significant factor in determining the risk of contact between the FPL and the fixation plate.…”