Background
Given the recent advances in the surgical intervention of distal radius fractures [
1,
2], posttraumatic deformity that may lead to alternation of biomechanics of the wrist and function impairment in the hand and forearm [
3‐
5] is still common sequelae in late-diagnosed fractures [
6‐
8]. Loss of the normal volar tilt in the sagittal plane, decreased radial inclination in the frontal plane, and loss of radial height have been reported to be common deformities following extra-articular fractures [
8]. Numerous surgical modalities in treatment of acute fractures of the distal radius have been proposed. Among these, intramedullary nails and locking plates are currently available devices for osteosynthesis after reduction and fixation [
9‐
11]. Both systems adopt a locking mechanism, in which a thread of the screw locks into the threaded hole in the intramedullary nail or the plate to create a fixed-angle construct for securing the distal metaphysis fragment. The aim of this retrospective study was to describe our experience using open osteotomy, local bone grafting, and fracture stabilization with two different devices for treatment of posttraumatic deformity in late-diagnosed fractures of the distal radius. The results were compared for intramedullary nailing and plating osteosynthesis based on clinical outcomes, radiographic analysis, and surgical complications.
Discussion
Malalignment following distal radius fractures may result in altered wrist kinematics [
4,
5] and midcarpal instability [
15] with reduced motion range and grip strength [
16,
17] and eventually lead to unsatisfactory outcomes. Given that the axial shortening of the radius affects treatment outcome in healed extra-articular fractures, the loss of radial length should be a critical predictor [
18]. Therefore, the restoration of the anatomical alignment is the primary goal in treatment of posttraumatic deformity of the distal radius and rigid fixation is crucial to prevent secondary collapse and displacement. Fundamentally, the aim of the extra-articular osteotomy is to restore the volar tilt in the sagittal plane, radial inclination in the frontal plane and radial length [
13,
19]. Various techniques have been described [
20‐
22]. Open wedge osteotomy has been considered the preferable technique and can be performed in either a dorsal or palmar approach; however, the dorsal approach may compromise wrist flexion due to scarring and implant irritation [
23]. In our study, better wrist flexion and patient satisfaction were achieved in the intramedullary nail group (group A) using dorsal open wedge osteotomy and intramedullary fixation. While favorable results could be attributed to more effective osteotomy and less invasive surgical approach used in the nail group, larger sample size and control studies would be necessary to clarify the clinical relevance and functional impact of patient satisfaction and radiographic outcome.
Osteosynthesis with dorsal and/or volar plates allows accurate reduction and secure fixation by sufficient exposure and direct visualization. Criticisms have been raised regarding wide tissue dissection and tendon attrition with internal fixation plate [
24]. In our series, as many as 24% of cases in the plate group requested subsequent implant removal. The design of juxta-articular seating could be a potential weakness; however, this was the only locking plate available when we started the treatment protocol, and still commonly adopted currently because of simplicity in application. Implant-related soft tissue irritation was uncommon in our experience. A significantly higher incidence of implant-related complications may, at least partially account for the lower satisfaction in the plate group. Surgical complications of intramedullary nail fixation may include dorsal superficial radial sensory nerve injury and potentially suboptimal reduction due to inadequate surgical exposure [
25]. Higher percentage of transient paresthesia in the nail group should caution the surgeon to aim for a more meticulous soft tissue and to protect the nerve during surgical dissection.
While most authors agreed that intramedullary nails yielded comparable surgical outcomes in acute fractures of the distal radius [
23‐
30], only a few of studies indicated the application of intramedullary nails in malunion [
31,
32]. In 2 previous studies, the technique and effectiveness of an intramedullary nail combined with bone graft or graft substitute has been demonstrated for the correction of extra-articular malunions of the distal radius. However, there has been no comparison study for the 2 implants in distal radius malunions. Both plate and nail groups in our study exhibited encouraging functional outcomes. Radiographic analysis confirmed the efficacy in correction of all 3 parameters with a significantly better postoperative radial height and inclination in the intramedullary nail group. Although there has been no clear correlation between radiographic findings and functional end-results [
33], the values of the postoperative radiographic parameters achieved may be indicative of the quality of surgical realignment after corrective osteotomy. Since open wedge osteotomy instead of distraction osteotomy was performed in all our cases, we did not intentionally correct ulnar variance by lengthening the osteotomy gap. Therefore, our radiographic assessment did not include ulnar variance.
Several studies comparing intramedullary nail with a locking plate in the treatment of distal radius fractures are currently available in the literature [
28,
30,
34,
35]. All studies concluded that both devices achieved equally good functional outcomes; while a systemic review indicated that intramedullary nails facilitated favorable functional results with radiological and clinical parameters nearly equivalent to locking plates [
36]. These studies all focused on acute fractures; there has so far been no comparison study addressing distal radius malunion. We used eligibility criteria similar to those in a previous study [
32] to include all cases with nascent malunion of 4 weeks and more. The surgical technique used in deformity correction in nascent malunion was similar to that used in solid malunion, but could be achieved only through a mini-open incision [
12,
32]. A locally resected exuberant callus was used to fill the osteotomy gap in all cases. Recent studies have indicated there are no advantages from cortical and cancellous autografts in terms of radiographic and function results, provided sufficient reduction and stable fixation is achieved [
37,
38]. Nevertheless, more complex surgery would be necessary for complicated malunion with severe deformity and soft tissue contracture.
Our study encompasses all the limitations of a retrospective design by relying on medical records and operative notes for data collection. The surgical approach and fixation modality were empirically determined through the planning and experience of a single surgeon. The cases were not randomized and lacked a control group. Patient characteristics varied between two groups including age, sex, and dominant hand involvement; all those could be factors bias affecting the results while no significant difference. Despite being a cohort study including two surgical groups, the technique of open wedge osteotomy differed between the 2 groups as the use of an intramedullary implant required only soft tissue dissection limited to the exposed metaphysis.
Conclusion
Open-wedge osteotomy with either intramedullary nail or locking plate fixation is a feasible approach for deformity correction in late-diagnosed distal radius fractures. In the present study, both techniques yielded comparable functional and radiographic outcomes. However, the intramedullary nail seemed to facilitate restoration of radial height and inclination with better wrist flexion, less implant-related complications, and higher patient satisfaction. Considering the relative benefits of the surgical procedure, we recommend that both surgical modalities should be applied in nascent and solid malunions. Intraoperative nerve injury was found to be a critical concern, and surgeons should be cautioned when selecting suitable candidates and surgical approaches.