Functional and Radiographic Outcomes of Intraoperatively Decreasing the Coracoclavicular Distance to 50% of the Unaffected Side in Stabilization of Acute Acromioclavicular Joint Injury: A Retrospective Evaluation

No correlation exists between coracoid tunnel widening and loss of reduction after arthroscopic acromioclavicular fixation using tightrope system

PURPOSE

To detect the widening of the tunnel of the coracoid process after arthroscopic fixation of acute acromioclavicular joint (ACJ) dislocation using the TightRope system and its correlation with loss of reduction and functional scores.

METHODS

From 2016 to 2018, a prospective study was performed on twenty-three patients with acute grade III-V ACJ dislocation. Arthroscopic TightRope repair of the ACJ was performed. Coracoid tunnel widening was measured by CT, and the coracoclavicular distance was measured on the radiographs immediately postoperatively and at 12 months. The Constant Shoulder Score, Oxford Shoulder Score, Nottingham Clavicle Score and Visual analog scale were used as outcome measures at 12 months.

RESULTS

The coracoid tunnel diameter to horizontal coracoid diameter ratio increased from 22.8 ± 3.7% immediately postoperatively to 38.5 ± 5.5% at 12 months (p < 0.001). The coracoclavicular (CC) distance showed an increase from a mean of 10.8 ± 1.7 mm to a mean of 11.8 ± 2.5 at 12 months (p < 0.001). There was no correlation between the increase in the coracoclavicular distance and the patients' functional clinical scores or coracoid tunnel widening.

CONCLUSION

Coracoid tunnel widening and radiological loss of reduction occur after arthroscopic fixation of acute ACJ dislocation with the TightRope system. However, they do not correlate with each other or with the functional scores of the patient.

LEVEL OF EVIDENCE

Level IV.

Acromioclavicular and coracoclavicular ligamentous insertion distances depend on the scapular tilt and decrease with anterior direction of the inferior scapula angle

PURPOSE

A variety of reconstruction techniques exist for the operative treatment of a ruptured acromioclavicular and coracoclavicular ligamentous complex. However, the complication rate remains high; between 5 and 89%. The intraoperative distance between the clavicle, acromion and coracoid is important for the refixation quality. In this study, the influence of scapular deflection on coracoclavicular and acromioclavicular distances was analysed.

METHODS

The ligamentous insertions of 24 fresh-frozen human scapulae were exposed. The coracoclavicular and acromioclavicular ligaments were referenced and captured in a rigid body system using a three-dimensional (3D) measurement arm. The inferior angle of the scapula was manually pulled into maximum anterior and posterior deflection, simulating a patient positioning with or without dorsal scapular support, respectively. Based on the rigid body system, the distances between the ligamentous insertions were calculated. Statistical evaluation was performed by setting the distances in anterior deflection to 100% and considering the other distances relative to this position.

RESULTS

The scapular deflection had a considerable impact on the distance between the ligamentous insertions. Concerning the conoid ligament, the mean distance was almost doubled when the inferior angle pointed posteriorly compared to anterior deflection (195.3 vs 100.0%; p = 0.028). The insertion of the acromioclavicular capsule also showed a significant association with the direction of deflection (posterior = 116.1% vs. anterior = 100%; p = 0.008).

CONCLUSION

Dorsal support shifting the inferior angle of the scapula anteriorly reduces the distance between the ligamentous insertions. Therefore, a patient position on a shoulder table with posterior support of the scapula is recommended to reliability reduce the acromioclavicular joint.

Comparing the Efficacy of Anatomical Locked Plate Fixation with Coracoclavicular Ligament Augmentation to Hook Plate Fixation in Treating Distal Clavicle Fractures

OBJECTIVE

Hook plate fixation is the traditional method for treating distal clavicle fractures. However, in recent years, locked plate applications have emerged as a promising treatment method. This study aimed to compare the short- and mid-term clinical efficacy of anatomical locked plate fixation with coracoclavicular ligament augmentation using anchor nails to that of hook plate fixation in treating distal clavicle fractures.

METHODS

This was a retrospective single-center cohort study investigating patients with distal clavicle fractures treated between January 2016 and February 2019 in Zhongnan Hospital of Wuhan University. Fifty-nine eligible patients who underwent either anatomical locked plate fixation with coracoclavicular ligament augmentation using anchor nails (LPF&CLA group; 20 patients) or clavicle hook plate fixation (CHPF group; 39 patients) were included. The visual analog scale (VAS) and Constant-Murley shoulder scores were used to assess shoulder function. In addition, the coracoclavicular distance between the affected and unaffected shoulders (ΔCC distance) was measured to assess the reduction. Patients were followed up at 3 months, 6 months, and 1 year postoperatively. The comparisons between the two groups were made using Student's t-test, chi-square test, or Fisher's exact test, if appropriate.

RESULTS

Preoperative VAS scores were similar in both groups. At 3- and 6-month follow-up, the VAS score was significantly higher in the CHPF group than in the LPF&CLA group. In contrast, the Constant-Murley shoulder score was significantly lower in the CHPF group than in the LPF&CLA group. When the hook plates were removed, there was no statistical difference in both VAS (0.2 ± 0.4 in LPF&CLA group vs. 0.5 ± 0.5 in CHPF group, p = 0.05) and Constant-Murley shoulder (96.1 ± 3.1 in LPF&CLA group vs. 93.8 ± 5.2 in CHPF group, p = 0.08) scores at the last follow-up. Postoperatively, the ΔCC distance was 2.37 ± 1.93 mm in the LPF&CLA group and -1.56 ± 1.34 mm in the CHPF group. One year after surgery, ΔCC distance increased to 3.96 ± 1.17 mm in the LPF&CLA group and to -0.89 ± 1.39 mm in the CHPF group.

CONCLUSION

For distal clavicle fractures in which the coracoclavicular ligament is disrupted, anatomical locked plate fixation with coracoclavicular ligament augmentation achieved better functional recovery and less pain than hook plate fixation at the 6-month follow-up. However, the hook plate provided better reduction throughout the follow-up period and shoulder pain could be relieved using removal surgery. Therefore, locked plates with coracoclavicular ligament augmentation favors post-surgery pain relief while harvesting similar functional outcomes to hook plate fixation.

Comparing the Anatomical Landmarks Versus the Coracoid-Based Landmarks Techniques for Coracoclavicular Stabilization After High-Grade Acromioclavicular Injury: A Biomechanical Study

BACKGROUND

In acute high-grade acromioclavicular (AC) joint injuries, the aim of treatment is robust reduction and stabilization of the joint. The anatomical landmarks method is most commonly used for stabilization, but loss of reduction often occurs because of the suture tunnels.

PURPOSE/HYPOTHESIS

The purpose was to evaluate and compare the stability of coracoclavicular (CC) stabilization using the anatomical landmarks and coracoid-based landmarks techniques in treating a high-grade AC joint injury. It was hypothesized that stabilization using coracoid-based landmarks would provide better stability.

STUDY DESIGN

Controlled laboratory study.

METHODS

Twenty fresh-frozen cadaveric shoulders (8 male and 2 female pairs) were randomized into 2 operative technique groups: 10 shoulders in the anatomical landmarks group and 10 shoulders in the coracoid-based landmarks group. The CC ligaments and AC capsule were cut at the midlevel, and CC stabilization and AC capsule repair were performed. For the anatomical landmarks technique, two 2.5-mm clavicular tunnels were created at 25 and 45 mm from the AC joint, while for the coracoid-based landmarks technique, two 2.5-mm clavicular tunnels were drilled using the medial and lateral borders of the coracoid base to choose the tunnel sites. Before injury creation and after stabilization, each shoulder underwent a loading force of 70 N in the superior and anteroposterior directions, and the displacement distance and stiffness were compared between the 2 techniques using the paired t test.

RESULTS

The mean difference in displacement before and after stabilization was higher in the anatomical landmarks technique than the coracoid-based landmarks technique (1.82 ± 3.52 vs -0.18 ± 4.78 mm in the superior direction and 7.47 ± 9.35 vs 1.76 ± 3.91 mm in the anteroposterior direction), but none of the differences in displacement or stiffness were statistically significant between the groups.

CONCLUSION

No significant biomechanical differences in displacement or stiffness were seen between the anatomical landmarks technique and the coracoid-based landmarks technique.

CLINICAL RELEVANCE

Either stabilization technique can be utilized for repair of the CC ligaments in an acute AC injury setting.

Using a Modified Kirschner Wire to Pass the First Suture Under the Coracoid Base in Coracoclavicular Stabilization

The acromioclavicular (AC) joint injury is a common shoulder injury in sports medicine. Combined coracoclavicular stabilization with AC capsule repair is 1 of 2 preferred treatments in acute high-grade AC joint injury. In East-Asian populations, the surgeon prefers to pass the first suture under the coracoid base, which is difficult using only basic surgical tools. We propose using a modified K-wire to pass the first suture under the coracoid base.