Management of chronic unstable acromioclavicular joint injuries

Abstract

The acromioclavicular joint represents the link between the clavicle and the scapula, which is responsible for the synchronized dynamic of the shoulder girdle. Chronic acromioclavicular joint instability involves changes in the orientation of the scapula, which provokes cinematic alterations that might result in chronic pain. Several surgical strategies for the management of patients with chronic and symptomatic acromioclavicular joint instability have been described. The range of possibilities includes anatomical and non-anatomical techniques, open and arthroscopy-assisted procedures, and biological and synthetic grafts. Surgical management of chronic acromioclavicular joint instability should involve the reconstruction of the torn ligaments because it is accepted that from three weeks after the injury, these structures may lack healing potential. Here, we provide a review of the literature regarding the management of chronic acromioclavicular joint instability.

Level of evidence: Expert opinion, Level V.

Keywords: Anatomical ligament reconstruction; Arthroscopically assisted management; Chronic setting; Coracoclavicular ligaments; Scapular dyskinesis; Unstable acromioclavicular joint injuries.

Fig. 1

Superolateral intraoperative perspective of a left shoulder with a history of chronic ACJ dislocation, that was managed by means of a modified Weaver–Dunn procedure. a Visualization of the coracoacromial (CA) ligament previous to its transfer to the distal third of the clavicle. Sutures have already been passed through the bone tunnels. The most medial tunnel aimed to achieve coracoclavicular (CC) fixation. This suture was previously passed beneath the coracoid process. b Details of the final suture fixation. Sutures are passed through the bone tunnels created in the clavicle

Fig. 2

a Anterolateral perspective of a right shoulder positioned in the operating room, with a history of a chronic grade V ACJ injury. b Biceps-labrum complex viewed from the posterior portal. Notice the degenerative aspect of the biceps insertion, which indicates an associated glenohumeral injury

Fig. 3

a Semitendinous allograft after being sutured with a metal-core suture in both of its limbs. b Both limbs of the graft coming out of the clavicle once fixed in both tunnels with bio-tenodesis interference screws. The ZipTight is tied by threading the sliding suture in the washer. c AP X-ray of a right shoulder in which an anatomical reconstruction of CC ligaments with tendon allograft was performed in the chronic setting. Observe the trapezoid tunnel in the clavicle, lateral to the conoid tunnel in the clavicle, through which also passes the suspension device

Fig. 4

Reproduced with permission and copyright© of Arthroscopy Techniques, Elsevier. a The AC drilling guide is placed at the coracoid base with the sliding tube of the guide in the superior aspect of the clavicle, 4.5 cm medial to its lateral border (conoid native origin). A 2.4-mm K-wire is passed through the AC guide. b A cannulated 4.5- to 6-mm (depending on the graft diameter) drill is passed over the K-wire and comes out from the inferior aspect of the coracoid. c A shuttle 1-mm PDS suture is passed through the cannulated drill located in the trapezoid tunnel. The PDS is recovered with a grasper from the anterior portal. d Superior perspective of the clavicle in which both shuttle sutures are emerging from the tunnels. e The PDS that arises from the trapezoid tunnel in the clavicle is pulled out in a cranial direction to recover the limb of the graft that is going to surround the base of the coracoid at its lateral aspect, coming from its tunnel and then being directed laterally and superiorly, configuring the anatomical 'V' shape of the graft. f Once the graft has passed through both clavicle tunnels, the ZipTight is tied to the distal limb of the shuttle FiberWire that is still free in the conoid tunnel

Fig. 5

a Before the ZipTight is tensioned, the graft should be fixed in the clavicular portion of the conoid tunnel with a 4.5- to 5.5-mm (same diameter of the tunnel) bio-tenodesis interference screw. Reproduced with permission and copyright© of Arthroscopy Techniques, Elsevier. b Both limbs of the graft coming out of the clavicle when fixed in both tunnels with bio-tenodesis interference screws. The ZipTight is tied by threading the sliding suture in the washer. To avoid any harm to the sutures of the ZipTight with the screw, the graft should be placed in an intermediate position between the screw and the sutures. c The ZipTight has been tied by pulling alternatively on both limbs of the blue traction sutures in a cranial direction to make the washer go down until it touches the clavicle and self-locks, providing mechanical stabilization of the reconstruction. d Both limbs of the graft are crossed over each other and sutured to themselves. The remnant of the graft is sectioned and removed

Fig. 6

a Final arthroscopic view from the lateral portal. The graft is coming out of the coracoid tunnel, ascending toward the trapezoid tunnel in the clavicle. The flip of the ZipTight is supported in the inferior aspect of the coracoid. b Final anatomical 'V' configuration of the CC reconstruction, with the flip of the ZipTight supported in the inferior aspect of the coracoid and both limbs of the graft are crossed over each other and sutured to themselves. Reproduced with permission and copyright© of Arthroscopy Techniques, Elsevier

Fig. 7

a and b Posterior perspective of two patients performing shoulder forward flexion. Notice that the inferomedial border of the right scapula (red arrows) shows a prominence. These two patients had a history of chronic unstable ACJ injuries that were conservatively treated