A systematic review and meta-analysis of the pronator quadratus repair following volar plating of distal radius fractures

BACKGROUND: Distal radius fracture (DRF) is the most common upper extremity fracture that requires surgery. Operative treatment with a volar locking plate has proved to be the treatment of choice for unstable fractures. However, no consensus has been reached about the benefits of pronator quadratus (PQ) repair after volar plate fixation of DRF in terms of patient-reported outcome measures, pronation strength, and wrist mobility. METHODS: We searched the PubMed, Embase, Cochrane Central, and China National Knowledge Infrastructure (CNKI) databases up to March 13, 2020, and included randomized-controlled, non-randomized controlled, or case-control cohort studies that compared cases with and without PQ repair after volar plate fixation of DRF. We used a random-effects model to pool effect sizes, which were expressed as standardized mean differences (SMDs) and 95% confidence intervals. The primary outcomes included Disabilities of the Arm, Shoulder, and Hand scores and pronation strength. The secondary outcomes included the SMDs in pain scale score, wrist mobility, and grip strength. The outcomes measured were assessed for publication bias by using a funnel plot and the Egger regression test. RESULTS: Five randomized controlled studies and six retrospective case-control studies were included in the meta-analysis. We found no significant difference in primary and secondary outcomes at a minimum of 6-month follow-up. In a subgroup analysis, the pronation strength in the PQ repair group for AO type B DRFs (SMD = − 0.94; 95% CI, − 1.54 to − 0.34; p < 0.01) favored PQ repair, whereas that in the PQ repair group for non-AO type B DRFs (SMD = 0.39; 95% CI, 0.07–0.70; p = 0.02) favored no PQ repair. DISCUSSION: We found no functional benefit of PQ repair after volar plate fixation of DRF on the basis of the present evidence. However, PQ muscle repair showed different effects on pronation strength in different groups of DRFs. Future studies are needed to confirm the relationship between PQ repair and pronation strength among different patterns of DRF. REGISTRATION: This study was registered in the PROSPERO registry under registration ID No. CRD42020188343. LEVEL OF EVIDENCE: Therapeutic III