We conducted a retrospective analysis of 47 patients and compared two techniques: open reduction and closed reduction, following internal fixation. To the best of our knowledge, this is the first study that compares the two techniques in complex femoral diaphyseal fractures, AO/OTA type-32C. Open reduction achieved a better anatomical reduction and improved bone union in complex femoral diaphyseal fractures.
The rate of nonunion after IMN of femoral shaft fractures ranges from 1–20% [16]. Delayed union or nonunion after IMN is more frequent in complex fractures [16]. In our study, the overall rate of union was 81.39% at 12 postoperative months, corresponding to the rate in the previous study. Additionally, early intervention with dynamization or secondary bone grafting for the management of delayed union is helpful in facilitating bone union.
Some disadvantages of the open technique have also been described, which include higher complication rates, increased infection rates, and decreased union rates [17]. Traditionally, closed reduction is said to preserve the soft tissue integrity and blood supply, leading to satisfactory prognoses [2, 18–20]. However, several studies have shown that open reduction has similar to superior outcomes [6, 21–23]. In our study, the open reduction group had a shorter time to union (7.39 vs. 9.18 months, p = 0.025) and significantly better strength of union in the early postoperative stage. The open reduction group had a higher RUSF at 6 postoperative months (9.30 vs. 7.76, p = 0.02) and 9 postoperative months (10.80 vs. 9.94, p = 0.03); there was no statistical difference between the two groups at 12 postoperative months (11.19 vs. 11.41, p = 0.37).
Regarding adverse outcomes, the overall risk of nonunion or infection was different between the two groups in this study. The difference in the revision surgery rate was not significantly different between the groups. Besides, the revision surgery rate in the closed reduction group was slightly higher (19.23% vs. 23.52%, p = 0.964). Therefore, open reduction and IMN of femoral shaft fractures did not significantly disturb union processing or predispose to complications. These results suggested that preservation of soft tissue integrity in complex femoral diaphyseal fractures was limited, due to the compromised vascular bed and severe soft tissue injury following high-energy trauma in such cases.
We speculate that a properly executed open reduction technique may result in better postoperative outcomes than a poorly performed open reduction, which leads to a large gap with a great predisposition to complications. In our study, the rate of anatomical-to-small gaps in the open reduction group was 96.15%, which was higher than that in the closed reduction group (96.15% vs. 47.05%, p = 0.01). In addition, three out of four patients with complications in the closed reduction group had large gaps; furthermore, one patient had a femoral malrotation due to poor reduction and biomechanical abnormalities and required re-operation in the acute postoperative phase. The effect of the presence of a third fragment and residual gap has been investigated in several studies [6, 21, 22]. The residual gap persists after closed reduction [3, 4], indicating a worse bone environment from huge fragment diastasis, potential soft tissue interposition, and poor axial load-bearing ability [2, 3]. Furthermore, the excessive fragmentary motion between the large gap has a negative effect on callus formation [24, 25]. The vascular supply to the reversed fragments may be strangulated and become compromised in the setting of an altered morphology [6]. Hamahashi et al. concluded that among the risk factors of delayed union, displacement is the only risk factor that could be modified with intraoperative reduction [21]. Achieving a quality reduction, eliminating the third-fragment effect, and facilitating bone union are more likely with the open reduction technique than with closed reduction.
Primary bone grafting can be performed through the incisional wound and help to achieve a better quality of reduction. Although this issue is controversial, primary bone grafting for complex long bone diaphyseal fractures is recommended [26–28]. Among these orthobiologic agents of bone enhancement, the evidence supporting the use of bone grafts is strong, whereas the evidence for the use of demineralized bone matrix and synthetic ceramics is moderate [29, 30]. In our open reduction group, primary bone grafting with reamed intramedullary autografts was performed in all patients. In this study, the time to union was significantly shorter in the open reduction group than in the closed reduction group (7.39 vs. 9.18 months, p = 0.025), suggesting that open reduction may result in a better quality of reduction and enhance additional bone healing.
The difference in outcomes between closed and open nailing in femoral diaphyseal fractures is controversial [31–33]. Therefore, individualizing treatment will be a better approach. Syed et al. suggested that in cases where closed reduction is difficult, i.e., it cannot be achieved in 15 minutes, it is better to use open reduction [17]. From our study, open reduction may be beneficial in complex femoral diaphyseal fractures (AO/OTA type 32C), by restoring the anatomical gap and facilitating primary bone grafting.
The limitations to this study, including the relatively small sample size and the short follow-up duration, may have an impact on the outcomes and led to different conclusions. Additionally, only radiographic outcomes were presented. Further studies on clinical outcomes and radiographic findings are mandatory to confirm our findings.