Acromioclavicular Joint Reconstruction with Recessed Clavicular Implant Technique Guide

Anterior and coracoid base tunnel location combined with single -or double clavicular tunnel techniques using double-button fixation for coracoclavicular ligament reconstruction both restore horizontal stability. A biomechanical cadaver study

BACKGROUND

The placement of clavicle tunnels in coracoclavicular ligament reconstruction is well established, but the optimal position of the coracoid tunnel remains unclear. This study aimed to investigate how the coracoid tunnel's position affects horizontal stability during coracoclavicular ligament reconstruction using a double-button technique.

METHODS

Fifteen fresh frozen shoulder cadaver specimens were tested under various conditions: intact coracoclavicular ligaments, disrupted ligaments, and reconstructions with a single coracoid and clavicle tunnel or double clavicle tunnels. The coracoid tunnel was positioned at the coracoid base 1/9, and 1/5 anterior to the base. Specimens underwent displacement-controlled loading, with 2D motion analysis conducted on captured digital images using TEMA motion analysis.

FINDINGS

Mean displacement for intact coracoclavicular ligaments was 1.61 ± 0.92 mm, and 3.69 ± 1.09 mm for disrupted ligaments. For reconstructed conditions, displacements were as follows: Single-Tunnel Base (1.87 ± 0.64 mm), Single-Tunnel 1/9 (2.54 ± 1.13 mm), Single-Tunnel 1/5 (2.62 ± 1.17 mm), Double-Tunnel Base (1.25 ± 0.73 mm), Double-Tunnel 1/9 (2.03 ± 1.22 mm), and Double-Tunnel 1/5 (1.88 ± 1.20 mm). Differences among intact, reconstructed, and disrupted states were statistically significant (p = 0.01-0.0001), with all reconstruction techniques restoring horizontal displacement near the intact state.

INTERPRETATION

At point zero both single coracoid tunnel and single- and double-clavicle tunnel restored horizontal displacement to its intact state. Coracoid tunnel placement anterior to the base of the coracoid did not influence horizontal displacement but single coracoid at the coracoid base and single clavicle tunnel resulted in the most anatomic reconstruction. Single coracoid tunnel at the base and double-clavicle resulted in the most stable reconstruction.

Treatment of Acromioclavicular Joint Instability With a Tunnel-Free Reconstruction Technique

Acromioclavicular joint injuries are a common shoulder injury encountered by orthopaedic surgeons. Many different surgical techniques have been described for the operative treatment of these injuries with no single, clear gold standard technique on which surgeons agree. Among the most common complications after surgical management of acromioclavicular injuries are loss of reduction, infection, fracture of clavicle or coracoid, and need for reoperation. We propose an arthroscopic-assisted, tunnel-free surgical technique using a tibialis anterior allograft combined with a FiberTape Cerclage (Arthrex, Naples, FL) to manage both acute and chronic acromioclavicular joint injuries. No bony tunnels are drilled and no hardware is implanted, which should obviate the risk for subsequent bony failure through a fracture, nor require subsequent hardware removal. In addition, the combination of suspensory and allograft fixation should impart sufficient stability to maintain an adequate reduction even in the face of failure of one of the fixation methods.