The Pronator Quadratus Muscle After Volar Plating: Ultrasound Evaluation of Anatomical Changes Correlated to Patient-Reported Clinical Outcome

Abstract

Background: Repair of the pronator quadratus (PQ) muscle with sutures has been reported durable after volar plating of distal radius fractures (DRF). It is unclear how the muscle reacts if not repaired and if a retracted muscle correlates to worse functional outcome or complications. In this study, we use ultrasound to investigate the anatomy of the PQ muscle after volar plating with PQ repair or nonrepair and correlate the ultrasound findings with patient-reported outcome. Methods: Participants were recruited from a clinical trial where they were randomly allocated to repair or nonrepair of the PQ muscle after volar plating of DRF. The participants and radiologist were blinded to group allocation. Ultrasound imaging of both fractured and contralateral wrists was performed 3 months after surgery. Ultrasound measurements included the difference in length of PQ muscle between the injured and uninjured side, retraction of PQ muscle, and tendon complications. The length and number of retractions were correlated to complications and Patient-Rated Wrist Evaluation (PRWE). Results: The mean difference of the difference in length measurements was 4.4 mm in the nonrepair group and 2.7 mm in the repair group with a mean difference between groups of 1.7 mm. This was statically significant; however, there were no clinical or statistical differences in complication rate or PRWE between the two groups. Conclusion: The PQ length was significantly shorter and the number of retractions significantly larger without repair of the PQ muscle; however, neither length nor retraction correlated significantly with complication rate or PRWE.

Evaluation of sparing the pronator quadratus for volar plating of distal radius fractures: a retrospective clinical study

“…It was previously believed that the PQ muscle was less critical, and that the anterior rotator function was limited; however, this is not the case. Jesper Sonntag et al [ 41 ] concluded in a study that with or without repair of the PQ muscle after incision, ultrasound results showed that both were shorter than the healthy side. Still, the shortening was more significant in the unrepaired group.…”

Evaluation of sparing the pronator quadratus for volar plating of distal radius fractures: a retrospective clinical study

“…It was previously believed that the PQ muscle was less critical, and that the anterior rotator function was limited; however, this is not the case. Jesper Sonntag et al [43] concluded in a study that with or without repair of the PQ muscle after incision, ultrasound results showed that both were shorter than the healthy side. Still, the shortening was more signi cant in the unrepaired group.…”

Ultrasound-directed reduction of distal radius fractures in adults: a systematic review

“…Three studies showed statistically non-significant(p>0.05) increased manipulation success rate in the US assisted DRF reductions, [11,15,26]. Bozkurt et al, [40] showed a 97.5% success rate in US group but no number was available for the control arm. Esmailian et al, [41] showed a slightly lower rate of 94.2 % compared to 94.8% in the control group.…”

“…USA, [15,30], Canada, [26,29], Japan, [11], Iran, [17,28] and Turkey, [40]. All studies included adult population except for two studies, [15,16] which also included children but did not give a separate data for them, with the age range of 3-95 years.…”