Background
Sternoclavicular joint (SCJ) infectious arthritis is an unusual disease accounting for 1% of all bone and joint infections [
1]. Treatment of SCJ infection is difficult because of the close proximity of major vascular structures and lack of substantial overlying soft tissues [
2]. Surgery may be performed when conservative treatment fails. Surgical options include incision and drainage, curettage, and/or SCJ resection [
2‐
5]. These procedures require debridement of the structures stabilizing the SCJ, such as the anterior or posterior SCJ ligaments as well as costoclavicular and interclavicular ligaments, with relatively frequent involvement of the first and even second rib [
6].
Most patients with SCJ instability complain of discomfort, clicking, and pain because the joint is often dislocated [
7‐
9]. Therefore, an increasing number of surgeons consider it important to restore the joint stability to improve upper extremity function, resulting in the development of other methods such as tendon autograft and resection arthroplasty for SCJ instability [
8‐
11]. A standardized treatment for SCJ infection has not been established. This study proposes a three-stage procedure of debridement, bone transportation (BT), and tendon autografting to restore the clavicular length and SCJ stability. This procedure was utilized in six patients with infectious arthritis. Soft tissue reconstruction was combined with BT following SCJ resection. The study provides novel insights into the management of SCJ infectious arthritis.
Discussion
In the current study, a three-stage procedure with BT was used to treat six patients with SCJ infectious arthritis. The infection was controlled and the wound healed after the SCJ debridement. Following the BT, the clavicle length was restored using distraction osteogenesis. The six patients then underwent tendon autograft reconstruction of the SCJ without internal fixation. The mean follow-up was 16 months. It was found that only three patients were positive for oxacillin-sensitive S. aureus preoperatively. This indicates that the SCJ infection might be caused by other organisms. More experiments would be needed to elucidate the etiology. The DASH scores decreased and the Constant scores improved remarkably after the surgery. All the patients were satisfied with the therapeutic effect. No complications occurred postoperatively. These results suggest that the three-stage procedure with BT is effective and safe for treating patients with SCJ infectious arthritis.
An increasing number of studies have recommended several techniques for SCJ reconstruction, such as the figure-of-eight technique [
13], tendon of the sternocleidomastoid muscle grafting [
14], and sternocleidomastoid tendon grafting [
15]. For patients with SCJ infection, SCJ debridement should be conducted first. SCJ reconstruction can then be after the infection is controlled and the wound has healed.
There is currently on consensus on the best option for SCJ infectious arthritis. Song et al. found that simple incision, drainage, and debridement were ineffective, with possible recurrence of the infection [
2]. Another method capable of eradicating bone infection has been proposed for treating long bone infections, which includes wide debridement and placement of an antibiotic-loaded cement spacer followed by cancellous bone grafting during a second-stage operation [
16‐
18]. However, this method is unsuitable for SCJ infection because the extent of movement in the joint would hamper bone union between the cancellous graft placed in the gap and the proximal clavicle. Another problem is the difficulty of obtaining stable fixation between the cancellous graft and the proximal clavicle. These problems have been solved successfully in the present study. Mechanical stretching employed in the BT approach stimulates new bone formation in the gap between the gradually distracted fragments, and the gap is filled. BT is a safe technique for gradually restoring the bone to its original length. It uses the principles of distraction osteogenesis, as described by Ilizarov [
19]. To our knowledge, the present study presents the first successful implementation of the BT technique for treating SCJ infection. Bone healing was achieved in all the patients after the removal of the external fixator without the need for internal fixation or bone grafting. Moreover, neither the gross strength nor the ROM was limited on the affected side. All the patients returned to full activity without limitations.
The three-stage procedure with BT combined debridement, BT, and tendon autografting. Tendon autografting was the third treatment stage in the present study. Bak et al. have reported that mini-open SCJ reconstruction using a tendon autograft can markedly improve the shoulder function of most patients with symptomatic anterior SCJ instability, although 68% of patients complained of donor-site morbidity, and 40% still had some discomfort at follow-up [
8]. In contrast, the DASH scores decreased and Constant scores improved remarkably after the three-stage procedure with BT. Furthermore, a satisfactory therapeutic effect was achieved in every patient. These findings indicate that the three-stage treatment with BT may be more effective and safer than SCJ reconstruction using a tendon autograft in patients with SCJ infectious arthritis.
In the study of Sewell and colleagues, the mean gradual clavicular length gained with distraction was 31 mm (15–41 mm), which corresponded to an average of 24.7% of the overall bone length. According to the literature, distraction exceeding 25% of the overall bone length may require additional plate fixation to consolidate the union [
20]. In our study, the resected clavicular length (mean 35 mm) was greater than that in the report of Sewel et al. However, the osteotomy site was not augmented with a plate and a bone graft, avoiding the risk and disadvantages with using an internal fixator.
A previous study has reported that three patients who underwent distraction at a rate of 1 mm/day required augmentation with a clavicular plate after fixator removal to prevent deformation and fracture of the regenerated bone [
20]. A relatively slow distraction might allow the regeneration of more blood vessels and periosteal cells in the gap created, thereby preventing the surrounding soft tissue from entering the gap. In the present study, the rate of distraction was 0.75 mm/day, and we did not encounter any problems that would require augmentation with a plate or a bone graft.
Although no complications occurred in the six patients in this study, the three-stage procedure of debridement, BT, and tendon autografting may cause some adverse effects, such as thoracic aorta injury and nerve injury. The important organs surrounding the SCJ are at risk of injury as well. Therefore, much attention should be paid to avoid complications when conducting the three-stage surgery.
The present study has several strengths. Firstly, it presents a novel approach wherein a combination of soft tissue reconstruction and BT is used after resection of the SCJ. Secondly, it suggests that distraction osteogenesis can be used not only in long bone defects but also in short and thin bone defects, in particular, in the case of the clavicle. The study also has some limitations. This method requires that the patients wear an external fixator for about half a year, which can cause inconveniences. Moreover, the number of patients was small, and a control group without lengthening was not employed. DASH and Constant scores were not measured prior to the second procedure (BT) to determine whether improvements were due to the three-stage procedure or simply the excision. Additionally, some recall bias might exist in both the clinical and functional data that we collected. Further studies will address these issues and validate the findings of this study.