Management of Acute Distal Radioulnar Joint Instability Following a Distal Radius Fracture: A Systematic Review and Meta-Analysis

Distal Radioulnar Joint Instability

SUMMARY

The distal radioulnar joint (DRUJ) is vital to the stability and function of the wrist and forearm. The osseous morphology is variable and provides little stability. A complex of confluent soft tissues is the primary stabilizer; however, the contribution of each component has yet to be elucidated. It has become increasingly clear that the anatomic fixation of distal radius fractures restores DRUJ stability, obviating the need for additional DRUJ stabilization. This review will describe the anatomy and biomechanics of the DRUJ and discuss injury patterns, treatments, and clinical results.

[Concomitant injuries of the wrist, distal ulna and distal radioulnar joint in distal radius fractures : Primary operative cotreatment vs. healing with no additional treatment]

Distal radius fractures are the most common fractures in adults and account for one quarter of all fractures, with increasing incidence. The number of patients and the requirement of an exact treatment are high. Continuous developments in diagnostic and operative possibilities enable in many cases a high-quality treatment with good clinical outcome; however, radius fractures rarely occur alone but in combination with additional fractures or ligamentous injuries. The frequency and extent of these injuries are not linked to the complexity of the primary injury. The aim is to recognize and correctly diagnose potential concomitant injuries. Many injuries do not need immediate treatment but heal without additional treatment after the radius has been treated. It is important to recognize those injuries which can cause severe complications if untreated; however, exactly this is often difficult. In many cases there is still no consensus if and how concomitant injuries should be treated. This article highlights the most frequent concomitant injuries in distal radius fractures with the possible advantages and disadvantages of cotreatment in order to facilitate decision making.

Analyzing the reduction quality of the distal radioulnar joint after closed K-wire transfixation in a cadaver model: is supination or neutral position superior?

INTRODUCTION

Distal radioulnar joint (DRUJ) instabilities are challenging and their optimal treatment is controversial. In special cases or when reconstruction of the stabilizing triangular fibrocartilage complex (TFCC) fails, K-wire transfixation can be performed. However, no consensus has been reached regarding the rotational position of the forearm in which this should be done. Therefore, it was investigated whether anatomical reduction would best be achieved by transfixation in neutral position or supination of the forearm.

MATERIALS AND METHODS

Twelve cadaveric upper limbs were examined before dissection of the DRUJ stabilizing ligaments and after closed transfixation in both positions by C-arm cone-beam CT. Whether this was first done in neutral position or in supination was randomized. The change in the radioulnar ratio (RR) in percentage points (%points) was analyzed using Student's t-test. RR was used since it is a common and sensitive method to evaluate DRUJ reduction, expressing the ulnar head's position in the sigmoid notch as a length ratio.

RESULTS

The analysis showed an increased change in RR in neutral position with 5.4 ± 9.7%points compared to fixation in supination with 0.2 ± 16.1%points, yet this was not statistically significant (p = 0.404).

CONCLUSIONS

Neither position leads to a superior reduction in general. However, the result was slightly closer to the anatomical position in supination. Thus, transfixation of the DRUJ should be performed in the position in which reduction could best be achieved and based on these data, that tends to be in supination. Further studies are necessary to validate these findings and to identify influential factors.

Concomitant ligament injuries can be left untreated during surgery of distal radial fractures

Instability of the distal radioulnar joint and scapholunate dissociation may cause pain, functional impairment and subsequent arthrosis. There is no consensus about whether these injuries should be treated acutely in patients undergoing surgery for distal radial fractures. We conducted a prospective cohort study to determine whether concomitant distal radioulnar joint instability or scapholunate dissociation negatively influence patient-related outcomes in these patients. The primary outcome was the patient-reported wrist/hand evaluation at 6 and 12 months after surgery. Out of 62 patients, 58% and 27% had intraoperative distal radioulnar joint instability and scapholunate dissociation, respectively. No significant differences were found in patient-reported scores at follow-up between patients with stable and unstable distal radioulnar joints, nor between patients with and without scapholunate dissociation. Sixty-three per cent of patients with an unstable distal radioulnar joint during surgery were stable on retesting after 6 months. Our study suggests that a wait-and-see policy in these patients therefore seems reasonable.Level of evidence: III.

Comparative Analysis of Treatment Outcomes: Modified Ulnar Gutter Slab vs. Sugar Tong Slab for Distal Radioulnar Joint Instability Following Triangular Fibrocartilage Complex Repair

The standard treatment for distal radioulnar joint (DRUJ) instability involves repairing the triangular fibrocartilage complex (TFCC) and immobilizing the joint with a sugar tong slab, but this can cause elbow stiffness. To address this, a modified ulnar gutter slab was designed to enhance elbow mobility during immobilization. A prospective randomized controlled trial was conducted on 23 DRUJ instability patients who underwent arthroscopic TFCC repair. Two post-operative splinting techniques were compared: the modified ulnar gutter slab and the sugar tong slab. The assessment included the Disabilities of Arm, Shoulder, and Hand (DASH) score; elbow, forearm, and wrist range of motion (ROM); post-operative DRUJ stability; and complications. DASH scores at 4 and 6 weeks were not significantly different. However, the modified ulnar gutter slab improved elbow extension range of motion at 4 weeks (extension lag: 20.0 vs. 6.5 in the sugar tong group) (p = 0.011). Post-operative DRUJ stability was comparable between the two groups. Notably, one patient in the sugar tong slab group experienced complex regional pain syndrome (CRPS). The modified ulnar gutter slab offers a post-operative alternative after TFCC repair. It effectively immobilizes forearm and wrist motion while enhancing elbow mobility, potentially reducing post-operative elbow stiffness.

A Stepwise Intraoperative Protocol to Minimize Complications after Volar Plating

Background  Although outcome of volar plating is generally good, care should be taken to avoid specific iatrogenic and preventable complications, with an incidence reporting averaging 15%. Flexor tendon rupture due to a prominent plate, extensor tendon rupture due to a dorsal protruding screw tips, cartilage lesions due to intra-articular screw placement, loss of reduction due to insufficient stability, and persisting ulnar pain with distal radioulnar joint instability due to unstable triangular fibrocartilaginous complex lesions or unstable ulnar styloid base fractures all have been described. Purpose  We believe that a majority of these complications can be prevented by meticulous assessment of several intraoperative parameters during volar plating. Therefore, we introduce the WRIST protocol, a stepwise easy-to-remember manual that combines multiple fluoroscopic measurements to guide intraoperative decision making. Conclusion  Large prospective studies of the "WRIST" protocol are needed for validation. But we believe that it may help surgeons to optimize surgical technique, functional and radiographic outcome, and prevent complications when treating distal radial fractures.

Stabilization of the Distal Radioulnar Joint with or without Triangular Fibrocartilage Complex Tear by an External Wrist Band Brace: A Cadaveric Study

The purpose of this study was to investigate whether a watch-shaped external wrist band brace improves distal radioulnar joint (DRUJ) stability. Seven fresh cadaveric arms were used. Using a customized testing system, volar and dorsal translation forces were applied to the radius externally while the ulna was fixed. The test was performed with the forearm in neutral, 60° pronated, and 60° supinated positions, once without the brace and once with the brace applied. In each condition, the amount of translation was measured. Then, the triangular fibrocartilage complex (TFCC) was detached from the ulnar styloid process and the fovea ulnaris, and the same tests were performed again. Detachment of the TFCC significantly increased volar and dorsal translations in all forearm rotations compared to the intact condition (p < 0.05), except for the pronated dorsal translation of the radius (p = 0.091). Brace application significantly reduced volar and dorsal translations in all forearm rotations both in intact specimens and in TFCC-detached specimens (p < 0.05), except for pronated volar and dorsal translations in TFCC-detached specimens (p = 0.101 and p = 0.131, respectively). With the brace applied, the TFCC-detached specimens showed no significant difference in volar or dorsal translation in all forearm rotations compared to the intact specimens (p > 0.05). The external wrist band brace improved DRUJ stability in both normal and TFCC-torn wrists and reduced the DRUJ instability caused by TFCC tear to a near-normal level.