Should We Repair the Pronator Quadratus in a Distal Radius Fracture with an Ulnar Styloid Base Fracture? A Biomechanical Study

The Outcome of under 10 mm Single-Incision Surgery Using a Non-Specialized Volar Plate in Distal Radius Fractures: A Retrospective Comparative Study

BACKGROUND

The distal radius fracture is a common orthopedic injury. We aimed to share the surgical steps and investigate the outcomes of treating distal radius fractures with wounds ≤10 mm using a globally accessible locking plate.

METHODS

We collected 46 patients who underwent surgery via a <10 mm wound, with a control group consisting of 40 patients who underwent conventional procedures. Both groups were treated using the same volar plate. We compared the radiographic reduction quality, including volar tilt angle, radial inclination angle, and ulna variance. Additionally, clinical outcomes, such as pain assessed using VAS, Q-Dash score, and PRWE, were evaluated. Patient satisfaction with the wound was also analyzed. The follow-up time for the clinical outcomes was 24.2 ± 13.47 months.

RESULTS

There were no differences in the quality of reduction in parameters such as the volar tilt angle (p = 0.762), radial inclination angle (p = 0.986), and ulna variance (p = 0.166). Both groups exhibited comparable results in pain VAS (p = 0.684), Q-Dash score (p = 0.08), and PRWE (p = 0.134). The ≤10 mm incision group displayed an increase in satisfaction with the wound (p < 0.001).

CONCLUSIONS

Treating distal radius fractures with a <10 mm wound using a non-specialized locking plate is a feasible approach. It does not compromise the quality of fracture reduction or functional scores and improves wound satisfaction.

MRI-Related Risk Factors for Distal Radioulnar Joint Instability

OBJECTIVE

Instability of the dorsal radioulnar ligament (DRUL) is caused by multiple factors from bony and soft tissue structures. Studies of DRUJ instability based on MRI have rarely been reported. This study aims to investigate related instability factors in the distal radioulnar joint (DRUJ) after trauma based on MRI imaging.

METHODS

The MRI imaging was performed on 121 post-traumatic patients with or without DRUJ instability from April 2021 to April 2022. All patients demonstrated pain or attenuated wrist ligamentous tissue quality with physical examination. The interesting variables, including age, sex, the distal radioulnar transverse shape, the triangular fibrocartilage complex (TFCC), DRUL, the volar radioulnar ligament (VRUL), distal interosseus membrane (DIOM), the extensor carpi ulnaris (ECU), and pronator quadratus (PQ), were analyzed using univariable and multivariable logistic regression model. The different variables were compared in radar plots and bar chart.

RESULTS

An average age of 121 patients was 42.16 ± 16.07 years. The 50.4% DRUJ instability existed in all patients and the distal oblique bundle (DOB) presented in 20.7% of patients. The TFCC (p = 0.03), present DIOM (p = 0.001), and PQ (p = 0.006) were identified to be significant in final multivariable logistic model. The percentage of patients with ligament injuries were general higher in DRUJ instability group. The patients with absent DIOM had a higher rate in DRUJ instability, TFCC, and ECU injury. There was higher stability in shape of C-type, intact TFCC, and present DIOM.

CONCLUSION

DRUJ instability is closely associated with TFCC, DIOM, and PQ. It could provide a potential for early detection of potential instability risk and taking necessary preventive measures.

Does access through the pronator quadratus influence pronation strength in palmar plate fixation of distal radius fractures in elderly patients?

INTRODUCTION

Palmar plate fixation of the distal radius fracture involves dissecting the pronator quadratus (PQ). This is regardless of whether the approach is radial or ulnar to the flexor carpi radialis (FCR) tendon. It is not yet clear whether and to what extent this dissection leads to a functional loss of pronation or pronation strength. The aim of this study was to investigate the functional recovery of pronation and pronation strength after dissection of the PQ without suturing.

MATERIALS AND METHODS

From October 2010 to November 2011, patients aged over 65 with fracture were prospectively enrolled in this study. Fracture stabilisation was performed via the FCR approach without suturing the PQ. Follow-up examinations took place 8 weeks and 12 months postoperatively, and pronation and supination strength were analysed by means of an especially developed measuring device.

RESULTS

212 patients were initially screened and 107 were enrolled. The range of motion compared to the healthy opposite side was Ext/Flex 75/66% 8 weeks postoperatively. Pronation was 97% with a pronation strength of 59%. After 1 year, the scores improved to Ext/Flex 83/80%. Pronation recovered to 99% and pronation strength to 78%.

CONCLUSION

The present study can show a recovery of pronation as well as pronation strength in a large patient population. At the same time, the pronation strength is still significantly lower 1 year after the operation than on the opposing healthy side. As the pronation strength recovers as the grip strength and is at all times on a par with the supination strength, we believe that we can continue to refrain from re-fixating the pronator quadratus.

Does pronator quadratus repair affect functional outcome following volar plate fixation of distal radius fractures? A systematic review and meta-analysis

Introduction

The study aimed to evaluate the efficacy of pronator quadratus (PQ) repair versus no repair following volar plate fixation of distal radius fractures.

Methods

A comprehensive search was performed in PubMed, CNKI, EMBASE, Web of Science, Ovid, and Cochrane Library databases. All randomized controlled trials comparing PQ repair with no repair in distal radius fractures before January 2023 were included. Two investigators independently screened eligible articles, assessed the study quality, and extracted data from included studies. Continuous variables used standardized mean difference and 95% confidence interval as efficacy statistics. The meta-analysis was performed using the Revman 5.4 software.

Results

A total of 430 patients in 7 RCT studies were included in this meta-analysis, of which 218 underwent PQ repair, while 212 patients underwent no repair. The results of the meta-analysis displayed statistically significant differences in grip strength (short-term), pronation angle (short-term), and pronation strength (short- and long-term) between the two groups. No significant difference in other outcomes was found between the two treatment arms.

Discussion

The repair of PQ may further increase grip strength and pronation function in the short-term and enhance long-term pronator muscle strength compared to no repair. However, due to the small number of articles included in the study, the above conclusions need to be verified by a larger sample and multi-center clinical study.

Residual stability of the distal radioulnar joint following ulnar styloid fracture: influence of the remnant distal radioulnar ligaments

Clinical studies suggest that even untreated basal ulnar styloid fractures may not affect patient outcomes. This may be due to the remaining parts of the distal radioulnar ligament still attached providing sufficient residual stability of the distal radioulnar joint. We tested this hypothesis in a biomechanical cadaveric model. Dorsopalmar translation of the distal radioulnar joint and forearm rotation were measured. Seventeen specimens were tested after a simulated ulnar styloid fracture including the fovea, followed by transection of the remaining palmar (n = 9) or dorsal (n = 8) portions of the distal radioulnar ligament and finally with all remnants transected. Rotation and translation both increased significantly after the final transection compared with the foveal fracture. The increase in translation was larger after transection of the dorsal remnants. We conclude that in an ulnar styloid fracture including the fovea, some ligament components are still attached to the ulnar head, giving residual stability to the distal radioulnar joint.

Role of Pronator Quadratus Repair in Volar Locking Plate Treatment of Distal Radius Fractures

Distal radius fractures are the most common type of upper extremity fractures, and their incidence is increasing. There has been a rise in the surgical treatment of distal radius fractures, primarily with volar locking plate fixation. Although this procedure is commonly done among orthopaedic surgeons, the role of pronator quadratus repair after fixation remains controversial. The pronator quadratus serves as a secondary forearm pronator and a dynamic stabilizer of the distal radioulnar joint. Aside from a functional role, repair of the pronator quadratus has been proposed to serve as a biologic barrier between the volar locking plate and the flexor tendons to minimize tendon irritation. In this narrative review, we discuss the current treatment trends, the surgical approach for volar locking plate treatment of distal radius fractures, and the anatomy and function of the pronator quadratus. We discuss the case for and against the repair of the pronator quadratus, both for function and prevention of flexor tendon irritation and rupture. The preponderance of high-level evidence demonstrates no benefit to pronator quadratus repair for pain relief or function. The current evidence does not conclusively support or refute pronator quadratus repair as a biologic barrier from the flexor tendons.