Medial placement of trapezoid tunnel leads to higher reduction loss in acute acromioclavicular joint dislocation treated with anatomic coracoclavicular fixation.

Aim: To analyze the association between clavicular tunnel positioning and postoperative reduction loss in patients with acute acromioclavicular (AC) joint dislocation treated with anatomic coracoclavicular (CC) fixation using double clavicular tunnels. Methods: A retrospective review of patients with AC joint dislocation, treated with anatomic CC fixation using double clavicular tunnels, was conducted. Patients with pre-operative, immediate post-operative, and final follow-up Zanca-view X-rays were included. On each X-ray, the obtained measures included: distance from lateral border of clavicle to trapezoid and conoid tunnels, distance between tunnels, clavicle length, and CC distance of affected and un-affected sides. Loss of reduction was calculated as CC distance difference between immediate and final post-operative X-rays. Association between reduction loss and tunnel positioning was analyzed. Results: Conoid, trapezoid and tunnel ratios were 24% ± 4, 15% ± 3, and 9% ± 2, respectively. Significant reduction loss was seen in 21(45.7%) patients. Significantly higher probabilities of reduction loss were associated with trapezoid tunnels placed medial to 24 mm (30.8% vs 65.0%, OR 4.2 (IC95%: 1.2-14.4), p: 0.024) or 15% of the clavicle length (32.1% vs 66.7%, OR 4.2 (IC 95%: 1.2-14.9), p: 0.025). Conclusions: Trapezoid tunnels placed medial to 24 mm or 15% medial to clavicle length could lead to higher probabilities of significant reduction loss. These findings support the importance of clavicular tunnels' proper placement for decreasing significant reduction loss.

Anatomic coracoclavicular ligament reconstruction with triple flip-buttons leads to good functional outcomes and low reduction loss: a case series.

BACKGROUND: The management of acromioclavicular (AC) joint dislocation remains controversial. Recently, anatomic coracoclavicular (CC) fixation with a double clavicular tunnel and three flip-buttons has shown promising results. This study aimed to evaluate functional and radiological outcomes in patients with high-grade AC joint dislocation treated with anatomic CC fixation using double clavicular tunnels and three flip-buttons. METHODS: A retrospective, unicentric study was performed. The study included patients with high-grade AC joint dislocation who underwent surgery with anatomic CC fixation using double clavicular tunnels and three flip-buttons. Demographic data were obtained from medical records. A functional evaluation using subjective shoulder value (SSV), visual analog scale (VAS), and disabilities of the arm, shoulder, and hand (DASH) questionnaires was performed, and an evaluation of preoperative and postoperative comparative Zanca view images was performed. Factors associated with functional outcomes and radiological AC reduction were analyzed. RESULTS: A total of 83 patients completed follow-up and were included in the analysis. The mean SSV, VAS, and DASH scores were 92.8, 0.8, and 6.4, respectively. Patients who had complications experienced significantly worse functional outcomes (DASH: P=0.037). Suboptimal final AC reduction was observed in nine patients (11.1%), and significantly more frequently in patients older than 40 years (P=0.031) and in surgeries performed more than 7 days after injury (P=0.034). There were two reoperations (2.4%). CONCLUSIONS: Anatomic CC fixation with a double clavicular tunnel and three flip-buttons leads to good functional outcomes, low complication rates, and high rates of optimal AC reduction. Level of Evidence: Level IV; Case series.