RHD can occur under various conditions and RHD in children requires prompt intervention. The main approaches used in children include closed reduction with casting and open reduction and internal fixation. Delayed or inadequate treatment in children may lead to complications such as pain, nonunion, loss of full range of motion or enlargement of the proximal end of the radius [
32]. In patients with annular ligament contraction into the joint space or those who suffered re-dislocation caused by an external force, stretching the ligament by manipulative reduction or other non-operative management is very difficult. In this study, chronic RHD children that failed closed reduction via manipulative reduction were enrolled to receive annular ligament reconstruction by suture anchor. Such studies in children are very few and more data is required to understand the best approaches for treatment in children. Therefore, we studied the clinical efficacy of suture anchor for reconstruction of annular ligament in children with RHD. Our study results showed that all patientsshowed excellent recovery with respect to pain and elbow function, suggesting that suture anchors for reconstruction of annular ligament may be highly effective in the treatment of children with chronic RHD or in children who failed closed reduction via manipulative reduction. Earlier studies reported that the material for construction is mostly palmaris longus tendon and triceps aponeurosis, and the procedure is accomplished by drilling tunnels in the ulna, bypassing around the radial neck after threading the construction materials through the bone tunnel [
32,
33]. Notably, reconstruction of annular ligament can also be achieved by palmaris longus tendon autograft, which is passed around the radial neck first and then through a bony tunnel to be sutured to itself [
17]. However, this surgical method is too complicated and requires ensuring that the longer graft can pass through the narrow ulnar tunnel, which could lead to ulna fracture [
34]. In this study, we used suture anchors to reconstruct annular ligament in children with RHD. A significant advantage of our approach is that the annular ligament reconstruction by suture anchorminimizes the risk of overcorrection of ulna in radial head [
35]. In addition, the small surgical incision of this technique may reduce stripping of the surrounding tissue and limit surgical trauma, resulting in better recovery of the ligament and wound (
http://d.wanfangdata.com.cn/Periodical_xdkf201009024.aspx). The anchors, with two long and absorbable sutures, weave the tendon around the ligament to strengthen the repair of the ligament, preventing re-dislocation of radial head [
36]. Previous studies suggested that the use of suture anchors save surgical time and minimize the size of surgical incision, compared to the tendon palmaris longus approach [
37,
38]. In addition, the fixation is highly effective in preventing re-dislocation of radial head, with fewer related complications [
39,
40]. Consistent with this, our study also demonstrates fewer post-operative complications. The radial head can remain in its original position to allow the growth of fibrous tissue around the sutures, even if the tendon graft fails. Additionally, the sutures cannot prevent the growth of radial head since they are absorbable [
25].
On the other hand, repeated dislocation and subluxation can have a huge impact on the articular surface and joint capsule, causing severe complications [
41]. Our results indicate that reconstruction of annular ligament is critical for the stability and maintenance of the reduction of radial head because annular ligament was accessed at the incision safely, with shorter operative time, and annular ligament is thick and sturdy with tough internal fixation and low-risk of re-dislocation [
6]. Due to the unique function of annular ligament in preventing RHD during rotation of forearms, radius spins inside the annular ligament against the ulna and allows axis rotation [
16]. Additionally, without the involvement of annular ligament when spinning, radial head will carry the translational motion, which is associated with the risk of leaving the proximal radio ulnar joint and anterolateral dislocation [
42]. Metallic anchors are associated with loosening, migration and chondral injury, and orthopedic surgeons are increasingly using bioabsorbable anchors to solve this issue [
25]. Bioabsorbable suture anchors are safe and mechanically stable implants, allowing arthroscopic surgeons to secure soft tissue to the bone in and around the shoulder [
25].
The current study has several limitations. First, the small sample size may limit statistical accuracy and universal application. In this study, only 20 children with RHD were recruited and the clinical efficacy of annular ligament reconstruction by suture anchor on RHD might be influenced by random variation. Second, the midterm follow-up and the potential lack of power to detect the complication rates may also influence the short-term and long-term clinical efficacy of annular ligament reconstruction by suture anchor on RHD. Thus, prospective studies and long-term follow-up is needed to further confirm whether suture anchor represents the optimal treatment for isolated old radial head dislocation.