A bipolar clavicle separation is defined as a simultaneous dislocation of the ipsilateral sternoclavicular joint (SCJ) and acromioclavicular joint (ACJ). This rare injury pattern is usually the result of a high-energy mechanism, such as a motor vehicle collision or fall from height. While there are several treatment options such as screw fixation, sutures, or plate fixations, there is no single standard approach for this infrequent injury. We describe a unique case of bipolar clavicle dislocation, specifically an anteriorly displaced SCJ and posteriorly displaced ACJ, treated with a novel surgical technique—a TightRope technique (Arthex®) and semitendinosus allograft.
Usually resulting from high-energy trauma, bipolar clavicle dislocations, also known as “floating” clavicles, occur when the clavicle simultaneously dislocates from the acromioclavicular joint (ACJ) and the sternoclavicular joint (SCJ) [
A 37-year-old right-hand-dominant male without any pertinent medical comorbidities presented to our orthopaedic department with left shoulder pain and a prominence of his sternoclavicular joint four months after being struck by a car while riding his bicycle. He was initially managed conservatively with a sling and denied any neurovascular issues. On subsequent follow-up, imaging revealed a malunion of an anteriorly displaced SCJ fracture dislocation and a Rockwood type IV acromioclavicular separation (Figures
(a, b) Plain radiographs demonstrating anterior dislocation of the sternoclavicular joint as well as a posterior acromioclavicular dislocation.
Axial CT scan demonstrating anteriorly displaced fracture dislocation of the SC joint.
(a, b) 3D reconstructions demonstrating anterior fracture dislocation of the SC joint.
Intraoperatively, the patient was placed upright in the beach-chair position. The Rockwood type IV acromioclavicular separation was addressed first by starting laterally with a vertical incision over the ACJ. The posteriorly dislocated clavicle was identified and carefully mobilized from the surrounding trapezius and reduced to a reasonable position confirmed by fluoroscopy. Next, the surgical incision was then carried horizontally across the clavicle to the SCJ and the manubrium. Careful dissection revealed a fibrous union between the SCJ and the medial end of the clavicle, which was anteriorly dislocated. Following resection of the fibrous tissue, the medial edge of the clavicle was partially resected to facilitate reduction back to the residual physeal scar. For maintenance of reduction, we reconstructed the anterior sternoclavicular ligament by using a semitendinosus allograft fashioned in a figure-of-eight type weave between the manubrium and clavicle. After completion of this step, the ACJ reduction was performed by passing a TightRope (Arthex®) from the lateral clavicle through the coracoid base under fluoroscopic guidance. Once the TightRope (Arthex®) was fully engaged, our fixation was deemed stable, and the surgical incision was closed in a sequential fashion.
The patient had no perioperative complications and was discharged from the hospital without issues. He was briefly immobilized for two weeks and then started range-of-motion training followed by strengthening. At his last six-month follow-up visit, the patient was very satisfied with his functional and clinical outcome. He reported minimal pain and only some stiffness with abduction of his shoulder. Overall, the patient maintained reduction and returned to working and recreational activities (Figures
(a, b) Plain radiographs demonstrating well-aligned acromioclavicular and sternoclavicular joints without hardware complication.
Bipolar clavicle dislocations, also known as traumatic “floating clavicles,” are rare with fewer than 30 documented cases [
The exact mechanism of bipolar clavicle dislocations remains uncertain; however, some authors have proposed multidirectional forces as a cause. Maruyama et al. suggested that the first rib plays a vital role in the pathophysiology of this injury, in which it acts as a pivot rotational point for the clavicle [
Understanding the forces at play is critical for management; however, there is no ideal treatment protocol for bipolar clavicle dislocations. Approaches have ranged from observation, isolated surgical treatment of the ACJ, to operative fixation of both ACJ and SCJ. In their series of 26 patients, Okano et al. reported that operative management yielded superior outcomes compared to purely conservative treatment. A significant percentage of these operative patients failed initial conservative management due to pain and decreased functional status, [
Our patient’s injury pattern was an anterior fracture dislocation of the SCJ and a Rockwood type IV ACJ separation. Studies have only reported a total of four cases with this particular type of injury pattern and discussed various surgical methods, such as surgical hook plates, that led to favorable results [
We present a rare case of a bipolar clavicle dislocation, and optimal treatment for these injuries remains controversial. The current study described the first successful treatment using a semitendinosus allograft to reconstruct the SCJ and an Arthex® TightRope to maintain the ACJ reduction.
Verbal informed consent was obtained from the patient(s) for their anonymized information to be published in this article.
We do not have any proprietary interests in the materials described in the manuscript. The authors declare that there is no conflict of interest regarding the publication of this paper.