Major bone defects in the forearm caused by severe trauma is often with combined with composite soft tissue defects, and even blood supply disorders. Ischemic time is the main criterion to decide whether to preserve or amputate limbs. For severe open forearm injuries, limb preservation is superior than amputation. Daoutis et al. [16] have reported the functional outcomes of 47 patients with replantation and evaluated the outcomes using Chen criteria [15], concluding satisfactory functional outcomes in 37 of the 42 patients. In 2007, Sabapathy et al. [17] have shown the functional outcomes of 22 patients with replantation and concluded that replantation is a valuable procedure, and radical debridement, appropriate bone shortening and reduction of ischemic time are of great significance for the successful replantation. In 2017, Mattiassich et al. [18] have reported long-term results of upper limb replantation and concluded that long-term effects are possible. In this study, according to the criteria of Chen, 3 patients had a grade-I functional outcome, 14 patients had a grade-II functional outcome, and 1 patient had a grade-III functional outcome. Apart from the time of injury, segmental comminuted fractures during debridement can lead to bone loss in the radius and ulna. In consideration of the two factors, rescue is a major challenge [17] [19], and requires highly personalized therapeutic approaches.
OBF reconstruction procedure has been used as a rescue option for complex forearm instability due to various causes. There is no consensus on the indications for this operation. According to previous studies, this operation is used to treat forearm bone loss caused by congenital abnormalities, tumors and infections [5-9].To our knowledge, the study by Peterson et al. [6] had the largest sample size among previous studies. In total, 19 patients received OBF reconstruction between 1973 and 1991 (only 1 case was caused by acute trauma, the rest cases were due to tumor resection / congenital abnormalities, etc.). According to the Peterson scoring system designed by Peterson et al. (the Peterson scoring system is also used in our study), 37% cases were excellent, 32% cases were good, 26% cases were fair and 5% cases were poor. Allende et al. [8] reported a mean clinical score of 7.7 (the Peterson scoring system [6]), without cases of infection, nonunion or re-fracture. In our case series, except for 1 patient was somewhat satisfactory, the remaining 17 patients were subjectively satisfied with limb reconstruction, and no one was willing to accept amputation, even if the limb was short and disfigured. Based on the Peterson scoring system, the outcome was excellent for 3 patients, good for 13 patients, fair for 1 patient, and poor for 1 patient. Except for 1 patient who failed to resume their original physical work and could only performed daily activities, the rest 17 patients can resume their original physical work. Kim SY et al. [9] retrospective analysis of the clinical data of patients who underwent OBF surgery from 1994 to 2014.,All patients had union with a mean follow-up of 83.6 months (range, 16-218 months). The mean pain score was 3 (range, 0-8), of which 3 were painless (score 0). The mean Quick DASH score was 39 (range, 7-75), and 4 patients had good or excellent results according to the 10-point score system used by Peterson et al. All patients were satisfied with the result. Five of 8 had complications related to soft tissues that were residual from their prior injuries and surgeries. One patient had post healing fracture requiring revision fixation and 1 had a postoperative infection requiring parenteral antibiotics.Therefore, OBF reconstruction combined with DRUJF is an alternative method to preserve severe acute forearm injuries and provides therapeutic ideas.
Sauvé-Kapandji procedure refers to the DRUJF and distal ulnar segment osteotomy pseudoarthrosis to treat forearm rotation dysfunction caused by changes in the distal radioulnar joint (DRUJ). Sauvé-Kapandji procedure can relieve inferior ulnar radial arthritis or mismatch by fusing the DRUJ, resolve ulnar variability through segmental resection of the distal ulna, and restores the forearm rotation function through the formed pseudo joint [20]. Simple OBF reconstruction can generally cause wrist longitudinal instability, DRUJ instability and chronic pain [10]. Ota et al. [21] also consider that the wrist width loss after Sauvé-Kapandji procedure is associated with the aggravated carpal ulnar deviation, therefore, attention should be paid to maintaining the original wrist width to prevent progressive ulnar deviation of the wrist. OBF reconstruction was generally used alone. And we also found cases of distal radioulnar dislocation after simple OBF reconstruction (Figure 1). We later performed DURJF as a salvage procedure. In this study, the OBF reconstruction combined with DURJF was simultaneously performed, which can theoretically maintain the line of force in the wrist for a long time, prevent the ulnar deviation and palmar subluxation of the wrist, and decrease the number of operations.
High-energy trauma can often result in comminuted long bone fractures of forearm, major bone defects, combined with skin and soft tissue defects. The upper limb defects can cause limb length differences, deformities and dysfunction, leading to therapeutic difficulties in clinical practice [22]. How to effectively repair major bone defects of forearm has always been an orthopedic problem. The traditional simple bone grafting is prone to various degrees of bone resorption and infection due to a lack of blood supply and the long bone healing time [23]. Anastomotic fibula segment transplantation to repair major bone defect of forearm can easily damage the posterior tibial blood vessels and the common peroneal nerve under improper operation. Meanwhile, microsurgical techniques are required, with relatively high technical requirements. In addition, a large number of muscles are attached to the fibula, thus, excision of the fibula segment can cause relatively great damage to the donor site; and fibula transplantation could also cause knee and ankle joint instability [23]. Induced membrane technique (IMT) for major bone defects of forearm requires repeated surgeries, and second-stage bone grafting requires bone removal from the autologous sacrum, with risks of pain and infection in the bone removal area [24]. Bone extension technology for major bone defects of forearm requires the long-term wearing of external fixators, with potential risks of nail channel infection and second-stage stump non-union. Yildiz et al. [25] have reported that mental problems (including anxiety, depression and paranoia) might occur in patients received external fixators for over 8 months. OBF reconstruction for major bone defect of forearm can repair the composite tissue damage of forearm within one single operation, which could significantly shorten the therapeutic course compared with previous surgical approaches, and renders early rehabilitation training. OBF reconstruction combined with DRUJF could simultaneously improve the rotation function of the forearm, avoiding wrist joint instability. However, it has shortcomings, such as weak bearing strength. In this group of patients, the average grip strength of affected limb was 39 kg (ranging from 1.8 to 7.5 kg), and no re-fracture or internal fixation fracture occurred throughout the follow-up. The most critical part of the operation is the osteotomy of ulna and radius. The length of the osteotomy should be conducive to the repair of soft tissues, especially the repair of blood vessels, nerves and tendons. Moreover, incision decompression of the forearm fascia is additionally required for cases with completely separated forearm.
There are certain limitations in this study. Although all data were prospectively collected, this study was a retrospective one. A prospective study involving a large population and long-term follow-up is required to confirm our results. In addition, a lack of a control group and statistical analysis in this study is correlated with the retrospective nature of this rare surgical procedure. The strengths of this study include a relatively homogeneous group of patients who suffered traumatic major bone loss in the forearm, and OBF reconstructions consist of the proximal ulna and the distal radius. Compared with other studies using telephone follow-up, face-to-face survey follow-up is used in our study, which avoids inconsistency between clinical results and patient evaluation as much as possible. Moreover, all the surgical procedures are performed by the same senior surgeon. Another advantage is the long-term follow-up, especially regarding the results of patient evaluations, which ranges from 2 to 16 years. To the best of our knowledge, it is the first case report with the largest sample size of the emergency treatment using OBF reconstruction combined with DRUJF to treat major bone defects in the forearm caused by severe trauma.