Volar versus combined dorsal and volar plate fixation of complex intraarticular distal radius fractures with small dorsoulnar fragment - a biomechanical study

Size and fixation options of dorsoulnar fragments in distal radius fractures

PURPOSE

This study aimed to investigate the influence of size and fixation options of dorsoulnar fragments on the clinical outcomes of distal radius fractures (DRFs).

METHODS

This retrospective analysis was performed on 94 patients with DFR accompanied by dorsoulnar fragments, spanning the period from October 2018 to November 2022. Mean follow-up was 15.5 (range, 12-20) months. Patients were divided into small- (<5 %, n = 28), middle- (5-15 %, n = 50), and large- (>15 %, n = 16) sized groups according to articular involvement of dorsoulnar fragments determined by three-dimensional (3D) computed tomography (CT) modeling. Subdivision also took place for the presence of postoperative fragment displacement (>2 mm) and fixation methods including volar locking plate (VLP), VLP combined with dorsal hollow compression screw (VDS), and VLP combined with dorsal low-profile mini plate (VDP). The radiographic parameters (volar tilt, radial inclination, and radial height) and functional outcome measures of wrist range of motion, wrist function (DASH, PRWE), and wrist pain (VAS) were evaluated and compared between groups.

RESULTS

Fracture healing was observed in all patients at final follow-up. No instances of dorsoulnar fragment displacement were observed in patients undergoing VDS and VDP treatment and the incidence of the dorsoulnar fragment displacement was 35 % (n = 8) in small-sized group, 21 % (n = 7) in middle-sized group, and 7 % (n = 1) in large-sized group when patients were treated with VLP. In small-sized group, no significant differences were found between patients with and without dorsoulnar fragment displacement in dorsiflexion restriction (10.6 ± 2.8°, 9.1 ± 2.3°, P = 0.159), pronosupination restriction (9.6 ± 2.1°, 8.6 ± 1.7°, P = 0.188), DASH (11.5 ± 4.1, 10.7 ± 3.2, P = 0.562), PRWE (11.9 ± 4.2, 10.6 ± 3.6, P = 0.425), and VAS (1.1 ± 1.1, 0.9 ± 1.0, P = 0.528). In middle-sized combined with large-sized group, the functional outcome measures of dorsiflexion restriction (12.5 ± 3.7°, 9.8 ± 2.9°, P = 0.022), DASH (14.6 ± 5.2, 11.4 ± 3.7, P = 0.030), and PRWE (15.0 ± 4.5, 11.3 ± 3.9, P = 0.016) were superior in patients without dorsoulnar fragment displacement. In patients treated with VLPs, no significant differences were found in dorsiflexion restriction (9.8 ± 2.5°, 10.8 ± 3.5°, 9.4 ± 2.5°, P = 0.299), pronosupination restriction (9.2 ± 1.9°, 10.1 ± 2.8°, 8.9 ± 1.5°, P = 0.200), DASH (11.1 ± 3.5, 12.9 ± 4.3, 11.1 ± 3.6, P = 0.162), PRWE (11.1 ± 3.9, 12.8 ± 4.2, 10.8 ± 3.9, P = 0.188), and VAS (1.0 ± 1.0, 1.4 ± 1.1, 0.9 ± 0.9, P = 0.151) between small-sized, middle-sized, and large-sized groups. In middle-sized group, no significant differences were found in dorsiflexion restriction (10.8 ± 3.5°, 9.4 ± 2.2°, 9.4 ± 2.4°, P = 0.316); pronosupination restriction (10.1 ± 2.8°, 8.8 ± 1.9°, 9.0 ± 2.5°, P = 0.314), DASH (12.9 ± 4.3, 10.3 ± 3.7, 10.5 ± 3.7, P = 0.133), PRWE (12.8 ± 4.2, 10.4 ± 3.8, 10.6 ± 4.1, P = 0.199), and VAS (1.4 ± 1.1, 0.8 ± 0.7, 1.0 ± 1.1, P = 0.201) between subgroups of VLP, VDS, and VDP. No significant differences were found in radiographic parameters between all groups compared.

CONCLUSION

This study indicated that the strict reduction and fixation of a dorsoulnar fragment might be not essential when its articular involvement was less than 5 %. The volar locking plate (VLP) fixation was commonly effective in treating distal radius fractures accompanied by a dorsoulnar fragment involving over 15 % of the articular surface. Additionally, the use of an additional dorsal hollow compression screw or a dorsal low-profile mini plate can get good wrist function in the early-term follow-up when the dorsoulnar fragment involve 5-15 % of the articular surface.

Management of complex wrist fractures with volar and dorsal locked (double-locked) K-lock

This article is a technical note to outline a novel technique of fixation in complex, comminuted distal radius fractures using a double-locked K-wire construct using a new implant called K-lock. In these (AO) C-type fractures, with significant dorsal comminution, it is often difficult to attain stable and secure fixation of the dorsal rim fragments, especially the dorsal lunate fossa fragment. This often results in patients being treated by temporary spanning devices or asking to have a restricted use of the hand during a given period to avoid loss of position. If dorsal plating is necessary, because of the severity of the comminution, a double-locked K-wire (locked in both the dorsal and volar plates) offers a fixation option and may create a significantly stronger construct and allow confident early mobilization. The K-lock was recently launched by Newclip Technics as an adjunct to the Xpert Wrist 2.4 set as a fragment-specific fixation option. The wire has less chance of displacing or fracturing the fragment and has a smooth surface compared with a screw; this wire would be safer close to the joint in severe distal intra-articular comminution. Of the 9 cases performed so far (as is our usual practice), despite the complexity of the fractures, none were immobilized postoperatively and all started hand therapy in the first week. Most were driving by 2 weeks and returned to light work at 4 weeks and heavy work or sports at 6 to 8 weeks. This principle of fixation may also be extended to other fractures where dual plating is used.

Volar Locking Plate Compared With Combined Plating of AO Type C Distal Radius Fractures: A Randomized Controlled Study of 150 Cases

PURPOSE

The optimal way to stabilize intra-articular distal radius fractures is unclear despite recent advances in surgical management. Volar plating is the most common treatment but may not be sufficient for more complex intra-articular AO type C fractures. The purpose of this randomized controlled study was to evaluate the radiographic and clinical outcomes following surgical treatment of AO type C distal radius fractures, comparing volar with combined plating.

METHODS

In this study, 150 patients were randomized to volar locking plate (n = 75) or combined plating (n = 75) following a distal radius fracture AO type C. The 1-year follow-up included radiographic outcome (Batra score), visual analog scale pain score, hand grip strength, wrist range of motion, Patient-Rated Wrist Evaluation score, and Quick Disabilities of the Arm, Shoulder, and Hand score.

RESULTS

Overall, 147 patients (median age 61 years) completed the 1-year follow-up (73 patients with volar plate and 74 with combined plating). No difference was found in radiographic outcome between the treatment groups. The volar plate group had significantly better Patient-Rated Wrist Evaluation scores, Quick Disabilities of the Arm, Shoulder, and Hand scores, hand grip strength, visual analog scale scores during activity, and flexion, extension, ulnar and radial deviation than the combined plate group. Hardware removal was performed in 10% in the volar plate group and in 31% in the combined plate group. There was no postoperative infection in the volar plate group but 3 cases in the combined plate group.

CONCLUSIONS

In patients with complex AO type C intra-articular fractures, volar and combined plating yielded the same radiographic result. The differences in Patient-Rated Wrist Evaluation and Quick Disabilities of the Arm, Shoulder, and Hand scores between the groups did not reach the thresholds for minimal clinically important differences, suggesting similar clinical outcome. The combined plating group had a considerably higher frequency of hardware removal and postoperative infections.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic I.