In contrast to many other fractures, there are have been a number of randomized studies on treatment of distal radial fractures. However, no clear conclusions can be drawn from meta-analyses of all randomized radial fracture studies as summarized in the Cochrane report (
Handoll and Madhok 2003b) where 48 randomized trials and 25 different treatment options were compared in 3,371 patients. Also, in a major meta-analysis (
Margaliot et al. 2005) of 46 non-randomized studies with either external or internal fixation in 1,519 patients, no clear conclusion could be drawn. Finally, in addition to the lack of consensus regarding the older established methods, no randomized or high-quality prospective non-randomized studies have been carried out yet for the newest concepts. We believe that these new concepts, such as the TriMed system used in the present study or the increasingly popular volar angle-stable plates, improve the treatment of unstable distal radial fractures.
To our knowledge, 4 randomized studies have compared open reduction and internal fixation to closed or indirect reduction. In a recent study by
Leung et al. (2008), a better result was found for internal fixation with AO plates either dorsally or volarly compared to bridging external fixation with augmentation with Kirschner wires at the surgeon's discretion. The other 3 studies have reported either an absence of significant differences or a better functional outcome for external fixation (
Kapoor et al. 2000,
Grewal et al. 2005,
Kreder et al. 2005). Grewal and co-workers
(2005) also found a higher complication rate for internal fixation with a dorsal plate than for external fixation. Kapoor and co-workers
(2000) concluded that open reduction and internal fixation provide the best articular anatomy in highly comminuted fractures, although the best outcome was achieved with the external fixator.
Grewal et al. (2005) compared internal fixation using the dorsal Pi-plate with mini-open reduction and external fixation, and found a higher complication rate for the Pi-plate. A better grip strength was found in the mini-open group but there were no significant differences in ROM or DASH.
Kreder et al. (2005) randomized 179 patients between either a mini-open indirect reduction and K-wires/screws or a full arthrotomy with internal fixation. A better result was found for the indirect group, but a high rate of crossovers from the indirect group to the open group at the time of surgery was reported and many patients were lost to follow-up.
Higher rates of infection and hardware failure have been reported in patients treated with external fixation and higher rates of tendon complications with internal fixation (
Margaliot et al. 2005). Thus, in the literature as well as in our study, the patterns of complications differ between the methods and might help the orthopedic surgeon to decide whether to use external or internal fixation. We found a high rate of complications, but most were minor and transient. In the external fixation group, the rate of major complications such as redislocation requiring reoperation or complex regional pain syndrome was higher. Other studies have reported complication rates of 20% and 85% with external fixation (
Anderson et al. 2004,
Capo et al. 2006), most complications being minor.
The malunion rate is an important outcome variable when evaluating different surgical treatments, and should be included in the overall decision. In our study, 5 cases in the external fixation group and 1 case in the internal fixation group had loss of reduction and malunions requiring further surgery. 5 other patients in the C group and 2 in the O group had radiographic malunion only. The malunion rate found by
McQueen (1998), comparing non-bridging external fixation to bridging external fixation, was similar to ours: 14 in the 30 patients treated with bridging external fixator.
Regarding grip strength, which was the primary outcome in the power analysis, the group that was operated with internal fixation had a better result, maybe less surprising, at 7 weeks, but more important also at 12 months. Also, regarding forearm rotation, the results were better in the internal fixation (O) group at all follow-up visits. The absolute values of grip strength and range of motion in the present study were similar to those in other studies, both in the C group (
McQueen et al. 1996,
Harley et al. 2004,
Wright et al. 2005,
Atroshi et al. 2006) and in the O group, and in the latter case both comparing to the TriMed system (
Benson et al. 2006,
Schnall et al. 2006) or to the latest fixation trends of angle-stable volar plating (
Musgrave and Idler 2005,
Wright et al. 2005).
There may be different explanations for the increased range of motion and grip strength in the internal fixation group after 1 year of follow-up. The fractures in the O group might be better aligned at surgery and/or a better reduction may be maintained during the healing, leading to a better congruency of the joint. In the O group rehabilitation starts 3 weeks earlier, which could explain the early difference between the groups, both regarding range of motion and grip strength, as found in previous studies (
Kopylov et al. 1999). However, in the present study, this effect persisted throughout the whole of the first year. Also, regarding the subjective outcome there was a tendency for there to be a better outcome in the O group.
The median DASH values in our series (9 in the O group and 14 in the C group) are similar to the results in other studies reporting DASH scores, around 16 for the volar plate (
Musgrave and Idler 2005,
Wright et al. 2005), between 9 and 17 for the TriMed system (
Konrath and Bahler 2002,
Benson et al. 2006,
Gerostathopoulos et al. 2007), and between 7 and 17 for external fixation (
McQueen et al. 1996,
Harley et al. 2004,
Wright et al. 2005,
Atroshi et al. 2006). This subjective outcome in both groups must be considered favorable, bearing in mind that in our study internal and external fixation was compared in the most unstable distal radial fractures.
In this group of patients with primarily unstable fractures, there is no acceptable alternative to surgery. The two methods we compared will both give a good result with good DASH values, good grip strength, and good range of motion after a year. Overall, considering the subjective and objective results as well as the rate of major complications and the sick-leave, we believe that internal fixation gives a superior result and in our opinion it would be the method of choice; however, results for the external fixator are still acceptable. Which method to use to internally stabilize the fracture is still a matter for discussion and should be the subject of future randomized studies. With smaller and smaller differences between the 2 methods, better and more sensitive subjective outcome instruments will be required if the number of patients needed to show a difference is to be kept within reasonable numbers.