Arthroscopically assisted 2-bundle anatomical reduction of acute acromioclavicular joint separations

Outcomes of arthroscopic coracoclavicular management for acromioclavicular joint injuries: A systematic review

Introduction

Various surgical procedures for coracoclavicular (CC) ligament repair have been described for symptomatic acromioclavicular joint dislocations, with none emerging as a clear gold standard. There has been increased interest in arthroscopic approaches. This systematic review evaluates clinical outcomes after arthroscopic surgeries used to treat chronic and acute AC joint dislocations.

Methods

We searched three databases (PubMed, EMBASE, and OVID [MEDLINE]) from database inception to December 20, 2022. Studies were included if they met the following criteria: studies evaluating humans, English language studies, level of evidence I to IV, and studies investigating clinical outcomes in patients following arthroscopic surgery for coracoclavicular ligament reconstruction. Studies on open reconstruction techniques only were excluded. Primary outcomes included function/pain scores, coracoclavicular distances, complications, and revision rates.

Results

Fifty-two studies were included. In 33 studies, postoperative Constant-Murley scores ranged from 82.8 to 99 points. Postoperative VAS scores ranged from 0.3 to 4.1 in 16 studies. In 46 studies, revision rates ranged from 0 % to 44.4 %. We did not observe a difference in revision rates between chronic and acute cases (P = 0.268). Complications were more common in chronic than acute cases (25.5 % vs. 16.4 %; P < 0.001).

Conclusions

Arthroscopic surgery for chronic and acute CC ligament injuries exceeds the MCID and PASS for several outcomes, with low failure rates. Arthroscopic CC reconstruction is a safe and effective alternative for chronic AC joint dislocations.

Level of evidence

IV (Systematic Review of Level I-IV Studies).

Comparison of Double Endobutton and Clavicular Hook Plate in Acromioclavicular Joint Disruption: A Systematic Review and Meta-analysis

BACKGROUND

Acromioclavicular joint (ACJ) disruptions are corrected by surgery either with an endobutton or a hook plate. The results in the long term were found to be similar in many randomized controlled trials. This study aims to conduct a meta-analysis to evaluate the functional outcome and complications of double endo button versus clavicular hook plate (CHP) for ACJ disruption (Rockwood types III-VI).

MATERIALS AND METHODS

Two authors independently searched related articles from electronic databases (PubMed, Google Scholar, MEDLINE, SCOPUS, and Web of Science) till January 26, 2022. The data were extracted from the related articles and analyzed by Stata software. For bias calculation of each study, the Newcastle-Ottawa scale and the RevMan 5.4 software were used.

RESULTS

14 cohort studies, 2 randomized control trial studies, and 1 case-control study including patients were selected in this meta-analysis. The results of our study showed a significantly higher Constant-Murley Score (WMD 5.79, 95% confidence interval [CI] 2.23-9.36), Visual Analog Scale (WMD- 0.63, 95% CI [-0.79, -0.46]) and University of California at Los Angeles shoulder score (UCLA) scale (WMD 3.32, 95% CI [2.87, 3.77]) for double endobutton group. At the same time, some complications like implant failure were more common in the double endobutton group.

CONCLUSION

This meta-analysis shows better functional and clinical outcomes of shoulder joint for the treatment of acromioclavicular joint (ACJ) disruption cases (Rockwood types III-VI) with no need for secondary operation, unlike the CHP. Complications like subacromial erosion, ACJ arthrodesis, and infection rate are higher in the CHP group, whereas the chance of implant failure is higher in the double endobutton group.

Choice of Acromioclavicular Dislocation Treatment Should Not Be Influenced by Risk of Development of Acromioclavicular Osteoarthritis: A Systematic Review With Meta-Analysis

BACKGROUND

It is currently unknown to what degree surgical or nonoperative treatment of acromioclavicular (AC) dislocation influences the development of osteoarthritis (OA). The aim of this study was to evaluate AC OA after surgical and nonoperative treatment for AC dislocations, compare OA prevalence between treatment options, and compare OA prevalence between the injured and contralateral shoulder.

METHODS

Articles reporting on the prevalence of OA after surgical or nonoperative treatment of an AC dislocation with a minimal 2-year follow-up were included. AC OA presence was extracted for the injured and contralateral shoulder. Treatment categories were defined based on anatomical variation in the reattachment of ligaments: AC fixation, coracoclavicular (CC) fixation, AC and CC fixation, Bosworth screw synthetic graft, tendon graft, and conservative. Study quality was assessed using the Methodological Index for Non-Randomized Studies (MINORS) criteria.

RESULTS

Ninety-four articles were included for qualitative analysis, and 7 articles were included for meta-analysis (n = 3,812; follow-up = 2.0-24.2 years; mean age 37.6 ± 10.4 years). A total of 3,483 patients underwent surgical treatment, and 329 patients underwent conservative treatment. OA prevalence ranged from 6.7%-29.3% between 7 pooled treatment categories. Most included studies had a follow-up <10 years (94%) and OA prevalence increased with time, regardless of treatment option. There was no difference in OA prevalence between the injured and contralateral shoulder (p = 0.120). MINORS scores were varied, ranging from poor to very good.

CONCLUSION

The pooled AC OA prevalence of the 7 treatment categories ranged from 6.7% for the CC fixation surgical group to 29.3% for the conservative treatment group. However, the included studies were predominantly of low quality and had varying follow-up periods, with most having relatively short follow-up durations. No difference in AC OA prevalence was found between the injured and contralateral shoulder. Based on the available evidence, treatment choice for AC dislocation should not be influenced by the potential development of AC AO.

LEVEL OF EVIDENCE

Level IV. See Instructions for Authors for a complete description of levels of evidence.

Coracoclavicular and acromioclavicular ligament reconstruction with a double-bundle semitendinosus autograft and cortical buttons for chronic acromioclavicular joint dislocations: clinical and imaging outcomes

BACKGROUND

There are few clinical and radiographic studies of coracoclavicular (CC) ligament reconstruction in chronic acromioclavicular (AC) joint dislocation. Additionally, reported AC joint reduction rates vary.

HYPOTHESIS

Arthroscopically assisted double-bundle semitendinosus tendon autografts with CC and AC ligament reconstruction for AC joint reconstruction provide AC joint stability and improved function at the final visit.

METHODS

In this retrospective study of prospectively collected data, 21 patients surgically treated for chronic AC joint dislocation (Rockwood III-V) were assessed clinically and radiographically preoperatively, and at day 1, 3 months, 12 months, and at a final visit (>24 months) postoperatively. Clinical assessments included Constant and American Shoulder and Elbow Surgeons scores. The CC vertical distance (CCD) on the affected and unaffected sides [CCD ratio (%)] on the anterosuperior view were measured. AC joint vertical reduction loss was defined as an increase in the CCD ratio of >25%. Horizontal AC joint instability was evaluated on axillary views. Pearsons' correlation coefficients were generated to examine the relationships among postoperative clinical scores, CCD ratio, interval from injury to surgery, and age at the time of surgery.

RESULTS

Twenty-one shoulders in 21 patients (mean age, 40.0 years at the time of surgery; 16 men, 5 women) were evaluated with a mean 31.7-month follow-up period. The mean Constant scores, American Shoulder and Elbow Surgeons scores, and CCD ratios significantly improved from preoperatively to the final visit (57.4 ± 10.1, 49.1 ± 12.1, 101.6 ± 64.1 preoperatively; 89.6 ± 5.3, 96.5 ± 4.2, 9.9 ± 34.5 at the final visit, respectively [P < .001 for all]). Vertical AC and horizontal AC joint instability were observed in 4 shoulders (19.0%) and in 1 shoulder (4.8%), respectively. However, there was no significant correlation between the increase in CCD and clinical scores at the final visit (Constant score; r = 0.179, P = .438: American Shoulder and Elbow Surgeons score; r = -0.260, P = .256) or the interval from injury to surgery (r = 0.099, P = .669) or age at the time of surgery (r = 0.019, P = .935). No clinical complications were associated with clinical symptoms.

CONCLUSIONS

Patients who underwent the index procedure achieved significant improvement in shoulder function without complications related clinical symptom after a mean follow-up interval of 31.7 months. In contrast, the rates of total ACJ instability in the vertical and horizontal planes were unsatisfactory but compatible with those in previous studies.

Long-term clinical and radiographic outcomes of arthroscopic acromioclavicular stabilization for acute acromioclavicular joint dislocation

BACKGROUND

Standard open acromioclavicular (AC) stabilization is associated with increased postoperative complications including deltoid injury, infection, tunnel complications, loss of reduction, and wound/cosmetic concerns. Arthroscopy may offer superior visualization and advantages that limit these risks. The aim of this prospective non-randomized study is to evaluate advantages and long-term reliability of arthroscopic AC stabilization.

METHODS

Thirty-two patients with acute grade III, IV and V AC dislocations underwent arthroscopic AC reconstruction with long-term assessment by clinical AC examination, Simple Shoulder Test, American Shoulder and Elbow Surgeons scores, visual analog scale, Specific AC Score and Quick Disabilities of the Arm, Shoulder and Hand scores. Radiographs verified conservation of initial reduction and presence of coracoclavicular (CC) ossifications. Complications, revision rate, and satisfaction were assessed and compared to the literature.

RESULTS

Mean follow-up time was 67.6 months. All clinical outcome scores improved and differences were statistically significant (P<0.001). Initial postoperative radiographs consistently showed complete reduction. Two patients experienced relapse to grade II AC dislocation without clinical implications. In total, 71.8% showed CC ossifications without functional impairment, and in 31.3% concomitant injuries were observed. Reintervention rate was 9.4%, and 96.9% of patients were satisfied with procedure outcomes.

CONCLUSIONS

Arthroscopic stabilization for acute AC joint dislocations offers satisfactory clinical and radiographic outcomes, and our results show that the arthroscopic technique is reliable in the long run. We report better reduction in maintenance, fewer complications, and similar reoperation rates compared to other techniques. Level of evidence: III.

Current trends in surgical treatment of the acromioclavicular joint injuries in 2023: a review of the literature

Background

This article examines the wide range of surgical reconstruction options available for acromioclavicular (AC) joint injuries. However, the lack of consensus regarding the most suitable surgical techniques is attributed to the high and variable failure rates observed with current approaches.

Methods

This article presents a comprehensive overview of the current surgical principles and techniques used by renowned experts in the field of AC shoulder injury management.

Results

It emphasizes the significance of addressing horizontal and rotational instability in AC injuries and highlights the impact of impaired scapular biomechanics.

Conclusion

By exploring these emerging concepts and strategies, the article aims to lay the foundation for future studies aimed at improving treatment outcomes and patient management.

Quality and stability of reduction of operated acromioclavicular dislocation using dual acromioclavicular and coracoclavicular stabilization

INTRODUCTION

Dual stabilization is advocated in acute acromioclavicular dislocation (ACD), but has been little assessed.

OBJECTIVE

This preliminary study performed clinical and radiological assessment of dual acromioclavicular (AC) and coracoclavicular (CC) stabilization in acute ACD. The study hypothesis was that dual stabilization allows satisfactory reduction that remains stable over time.

MATERIALS AND METHODS

A button was used under endoscopy for CC stabilization. For AC stabilization, a short approach was used; the joint was cleansed then stabilized by an anchored tape between the acromion and the clavicle to promote ligament healing. Clinical assessment was based on a visual analog pain scale (VAS), joint range of motion and Quick-DASH and Constant scores. Radiological reduction was assessed on the ratio of CC distance between the operated and healthy sides on two views. MRI was used in follow-up to screen for ligament healing: thickening and continuity.

RESULTS

Thirty-five patients with stage 3-5 acute dislocation were included. At a minimum 24 months' follow-up, mean clinical scores were very satisfactory, with recovery of motion and pain relief. Radiography showed 94% stable reduction in both vertical and horizontal planes. MRI confirmed CC and AC ligament healing. Postoperative complications mainly comprised 4 cases of reduction loss (11%). One clavicle fracture occurred, at 6 months.

CONCLUSION

Dual AC-CC stabilization provided very good radiographic reduction in both horizontal and vertical planes. Functional results were very satisfactory, and complications were few, with some cases of reduction loss. These good results encourage us to continue with dual stabilization in acute ACD.

LEVEL OF EVIDENCE

II; prospective cohort.

A Self-Designed Endobutton Installation Device for Coracoclavicular Stabilization in Acute Rockwood Type III Acromioclavicular Joint Dislocation

OBJECTIVE

Endobutton technique could provide flexible coracoclavicular (CC) stabilization for acromioclavicular joint (ACJ) dislocation and achieved good clinical outcomes. However, the difficult part of this technique was placement of the Endobutton to the coracoid base. In this study, we designed an Endobutton installation device to place the Endobutton at the coracoid base. And we examined the clinical and radiographic outcomes of patients with acute Rockwood type III ACJ dislocation repaired with Endobutton using this device.

METHODS

We designed an Endobutton installation device to place the Endobutton at the coracoid base to achieve CC stabilization. We retrospectively reviewed 42 patients with acute Rockwood type III ACJ dislocation who underwent CC stabilization with Endobuttons placed either using this novel device (group I, n = 19) or the traditional technique (CC stabilization without using special device, group II, n = 23) from January 2015 to April 2020. The two groups were compared regarding the operative time, intraoperative blood loss, and clinical and radiologic outcomes at final follow-up. The operation-related complications were also evaluated. The Student's t test and the Mann-Whitney U-test were used to compare differences in continuous variables. Differences in categorical variables were assessed with either the Pearson's chi-squared test or Fisher's exact test.

RESULTS

Forty-two patients were clinically followed up for a minimum of 12 months. Compared with group II, group I had a significantly shorter mean operative time (56.05 ± 7.82 min vs. 65.87 ± 7.43 min, p < 0.01) and significantly lesser mean intraoperative blood loss (67.89 ± 14.75 mL vs. 94.78 ± 25.01 mL, p < 0.01). At final follow-up, there were no significant differences between the two groups in the visual analog scale score for pain, Oxford Shoulder Score, Disabilities of the Arm, Shoulder, and Hand score, and postoperative CC distance of the affected side. Loss of reduction occurred in four patients in group I and three patients in group II (p = 0.68); there were no other operation-related complications in either group.

CONCLUSIONS

The Endobutton installation device makes placement of the Endobutton at the coracoid base easier and achieves satisfactory clinical and radiologic outcomes without additional complications in acute Rockwood type III ACJ dislocation.

Arthroscopic Anatomic Knotless Coracoclavicular Ligament Repair Without Coracoid Drilling

Acromioclavicular joint injuries are common in young active patients. A wide variety of surgical techniques exist to address specific complications associated with surgery. Complications after surgery include loss of reduction, fracture of the clavicle or coracoid, failure of fixation, and prominent and symptomatic hardware. This technique aims to reduce these complications with an arthroscopic anatomic coracoclavicular ligament repair using knotless adjustable loop buttons with fifth-generation suture tape and no drilling of the coracoid.

Management of Acute High-Grade Acromioclavicular Joint Dislocations: Comparable Clinical and Radiological Outcomes After Bidirectional Arthroscopic-Assisted Stabilization With the Single Low-Profile Suture Button Technique Versus Double-Suture Button Technique

PURPOSE

To compare the 2-year clinical and radiological outcomes of an arthroscopic-assisted bidirectional stabilization procedure using a single low-profile (LPSB) or double-suture button (DSB) technique with additional percutaneous acromioclavicular (AC) cerclage fixation for patients with acute high-grade AC joint dislocation.

METHODS

This retrospective cohort study compared male patients aged between 18 and 56 years with acute high-grade AC joint dislocation fixed with either a LPSB or DSB technique. Patients were examined at least 24 months after surgery. Subjective Shoulder Value (SSV), Taft (TF), and Acromioclavicular Joint Instability (ACJI) scores were evaluated. Coracoclavicular difference, ossification, AC joint osteoarthritis, and dynamic posterior translation (DPT) were assessed on bilateral anteroposterior stress radiographs and modified Alexander views. The revision rate due to implant conflict and duration of surgery were reported. Group outcome differences were analyzed using standardized hypothesis tests.

RESULTS

28 patients aged 39.2 (LPSB) and 36.4 years (DSB) (P = .319; CI: -2.77-8.34) were eligible per cohort. The follow-up was 30.5 (LPSB) and 37.4 months (DSB) (P = .02; CI: -12.73-1.08). LPSB patients rated a significantly higher SSV (93.2% vs 81.9% [DSB]; P = .004). TF and ACJI scores were similar between the groups. Coracoclavicular difference markedly decreased from 12 mm to 3 mm for both cohorts (P < .001). Ossification was identified in over 85% in both cohorts (P = .160; CI -0.77-0.13) and osteoarthritis in 21.4% (LPSB) and 39.3% (DSB) (P = .150). Persistent DPT was found in around 30% for both cohorts (P = .561; CI -0.26-0.48). The revision rates were 0% (LPSB) and 7% (DSB) (P = .491). LPSB surgery was shorter (59.7 vs 71.5 mins [DSB]) (P = .011).

CONCLUSIONS

The results of the LPSB and DSB techniques with additional percutaneous AC cerclage fixation showed comparable outcomes with excellent clinical and satisfactory radiological results. The assessment of the subjective patient satisfaction was in favor of the LPSB technique and no postoperative revision event was observed following this procedure.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Clinical outcomes for grades III-V acromioclavicular dislocations favor double-button fixation compared to clavicle hook plate fixation: a systematic review and meta-analysis

INTRODUCTION

The purpose of this study was to perform a systematic review and meta-analysis of both randomized controlled and observational studies comparing double-button suture fixation to hook plate fixation for types III-IV acromioclavicular joint dislocation.

METHODS

Systematic review of Medline, Embase, Scopus, and Google Scholar, including all levels 1-3 studies from 2000 to 2022. Clinical outcome scores, range of motion, and complications were included. Risk of bias was assessed using the Cochrane Collaboration's ROB2 tool and ROBINs-I tool. MINORS and modified Coleman Methodology Score (CMS) were used to assess within study quality. The GRADE system was used to assess the overall quality of the body of evidence. Heterogeneity was assessed using χ2 and I2 statistics.

RESULTS

Fifteen studies were included. Three of the four included LOE II and eleven of the LOE III studies had a high risk of bias. Study quality was considered poor and fair for 67% by MINORS criteria and 93% for CMS criteria. The pooled estimate (SMD 0.662) for all clinical outcomes was statistically significant and in favor of button repair (p = 0.0001). The pooled estimate (SMD 0.662) for all VAS pain scores was statistically significant, again in favor of button repair (p = 0.001).

CONCLUSIONS

The results of this meta-analysis demonstrated significantly better outcomes of button repair for acute ACJ dislocations when compared to clavicle hook plate. Button repair is also associated with a 2.2 times lower risk for complications. However, risk of bias is high, and study quality within and between studies was low. These results, therefore, must be viewed with caution.

LEVEL OF EVIDENCE

Level III; systematic review and meta-analysis.

Minimally invasive reconstruction of acute acromioclavicular joint injuries using the TwinBridge button system

INTRODUCTION

Acute acromioclavicular joint (ACJ) injuries are among the most common shoulder injuries in active young adults. The most frequently used surgical treatments include the hook plate implantation and arthroscopic treatment using flip-button systems. The aim of this study was to evaluate the results of treating acute ACJ injuries using a new minimally invasive implant based on a flip-button system.

MATERIAL AND METHODS

From January 2016 to October 2019, a total of 20 patients with acute ACJ injuries (1 × Type III, 3 × Type IV, 16 × Type V) underwent surgery using the Twinbridge implant (Smith & Nephew). It is a prefabricated construct consisting of two Endobuttons connected with an UltraTape. One button is placed under the coracoid using a special aiming device and two buttons are placed on the clavicle. Preoperatively, 1 day postoperatively, 3 months and at least 1 year postoperatively, patients were clinically examined and bilateral stress view and axial radiographs were obtained. At final follow-up, the simple shoulder test (SST), Taft score, Constant score, and ACJ instability (ACJI) score were recorded and a side-to-side ratio of the coracoclavicular (CC) distance was calculated.

RESULTS

All 20 patients were contacted at final follow-up at a mean of 28 (min. 13, max 50) months. Six patients were not willing to come for a clinical and radiographic examination and were contacted via telephone. All six patients were free of complaints. Another two patients free of complaints refused radiographs at final follow-up. The patients presented a mean SST of 99.6% (20 patients, min. 91.7, max. 100), Taft score of 11.6/12 points (12 patients, min. 10, max. 12), ACJI of 85.5/90 points (12 patients, min. 78, max. 90), and a Constant score of 97.1 (14 patients, min. 81.0, max. 100) for the affected shoulder. Preoperative stress view images revealed a mean side-to-side difference of the CC distance with a ratio of 1:2.34 (min. 1:1.80, max. 1:3.33). At final follow-up, CC distance was calculated with a mean ratio of 1:1.12 (min. 1.1, max. 1:1.38). Axial images showed a proper position in all cases. A "perfect" radiological result was achieved in six patients (50%) with a side-to-side CC distance of less than 10% (ratio 1:1.1 or less). A Rockwood type II result was achieved in five patients (42%) with a distance of 10 to 25% (ratio 1.11-1.25). One (8%) presented with a Rockwood type III result with a difference of more than 25% (ratio 1:1.38) and was considered a radiological failure.

CONCLUSIONS

When used correctly, the Twinbridge implant offers good-to-excellent clinical and radiographic results using a minimally invasive surgical technique. Complication rate is comparable to other button-systems.

[Minimally Invasive Techniques for the Treatment of Acute and Chronic Acromioclavicular Joint Instabilities]

Acromioclavicular joint instabilities are one of the most common injuries of the shoulder girdle. Diagnostic measures include the vertical and horizontal components of instability. The main goals of treatment include pain reduction, joint stabilization, and return to physical activity. For operative treatment, there are numerous techniques available. Recently, minimally-invasive techniques were developed and showed equal results as with open approach. These procedures facilitate simultaneous treatment of concomitant shoulder lesions and reduce soft tissue trauma as well as the risk of infection. This article presents an overview of such minimally-invasive techniques for both acute and chronic instabilities. Both techniques address the aspect of horizontal instability, which was found to compromise clinical results. For an acute injury, we describe the use of a low-profile button system combined with an additional acromioclavicular cerclage. In the chronic setting with a bidirectional (vertical and horizontal) instability, a free tendon graft combined with a single TightRope augmentation is recommended.

Long-term Clinical Outcomes After TightRope Versus Hook Plate Fixation for Acute Acromioclavicular Joint Dislocation

Background

There is limited information regarding the long-term efficacy of techniques for surgical fixation after acromioclavicular (AC) joint dislocation.

Purpose

To evaluate the efficacy of hook plate (HP) and TightRope (TR) fixation for acute AC joint dislocations by comparing the long-term clinical and radiological patient outcomes.

Study Design

Cohort study, Level of evidence, 3.

Methods

This study retrospectively analyzed data from 61 patients with acute AC joint dislocation between July 2011 and November 2015. The patients were grouped according to surgical procedure: HP (n = 36) and TR (n = 25). Clinical outcomes at final follow-up were evaluated using the visual analog scale (VAS) for pain; the American Shoulder and Elbow Surgery score; the Korean Shoulder Score; and the University of California, Los Angeles (UCLA) shoulder score. Side-to-side coracoclavicular (CC) distance on radiographs, postoperative complications, and the rate of subacromial erosion in the HP group were also assessed between procedures.

Results

The mean follow-up period was 7.0 ± 1.0 years, and there were no significant differences in pain or outcome scores between the HP and TR groups (all P > .05). Forward flexion was better in the TR group (172.6° ± 5.6°) versus the HP group (166.0° ± 10.8°; P = .002). The percentages of patients with a difference in the side-to-side CC distance of <5 mm were 83.3% and 72.0% in the HP and TR groups, respectively (P = .288). Complications were found in 2 patients in the HP group and 1 in the TR group (P ≥ .999). Subacromial erosion was observed in 41.7% of patients after HP fixation, with no difference in VAS pain scores at the final follow-up in patients with versus without subacromial erosion (P = .719).

Conclusion

When comparing HP with TR fixation for the treatment of acute AC joint dislocations, there were no significant differences in functional outcome scores, final CC distance, or complications. Slightly better forward flexion was seen after TR fixation. Subacromial erosion occurred in 40% of patients after HP fixation, but this did not affect long-term VAS pain scores. Both surgical techniques are effective treatment options for AC joint dislocation.

Subject-specific computational modeling of acromioclavicular and coracoclavicular ligaments

BACKGROUND

Disruption of the acromioclavicular joint is a common injury. Despite the different surgical procedures described for treating this injury, complications such as loss of reduction and failure of fixation remain unacceptably high. We developed a computer model of the acromioclavicular joint to better understand the biomechanical contributions of the ligaments that are typically injured.

METHODS

Six fresh frozen human cadaveric shoulders were tested on an AMTI VIVO 6-degree of freedom test platform to measure force-displacement in inferior translation, anteroposterior translation, and internal rotation before and after sequentially transecting the coracoclavicular and acromioclavicular ligaments. These data were used to construct computer models of each specimen. Three-dimensional computed tomographic scans were used to generate a rigid-body dynamics model using the AnyBody Modeling System. The scapula and clavicle were connected by the acromioclavicular joint capsule, the conoid ligament, and the trapezoid ligament. Subject-specific ligament properties were calculated by matching computer predictions to experimental force-displacement data.

RESULTS

The calculated free lengths of the conoid, trapezoid, and acromioclavicular ligaments were 13.5 (±3.2), 11.8 (±2.4), and 11.0 (±2.7) mm, respectively. The calculated stiffnesses of the conoid, trapezoid, and acromioclavicular ligaments were 34.3 (±6.3), 28.4 (±3.2), and 33.8 (±8.2) N/mm, respectively. Root mean square deviation (RMSD) of predicted force-displacement curves relative to experimental force-displacement curves (during inferior and anteroposterior translation) was less than 1 mm. For validation of subject-specific models, after ligament properties were calculated, the RMSD of the predicted torque over 15° of internal rotation was 12% of maximum rotational torque (average for 6 specimens).

DISCUSSION AND CONCLUSION

Acromioclavicular disruption results in multidirectional instability, which requires careful consideration of the individual contributions of the injured ligaments. In addition, variations in patient anatomy can significantly affect the biomechanical stability of the reconstruction. Subject-specific models can enhance our understanding of the individual and collective biomechanical contributions of the injured soft tissues to the multiaxial stability of the acromioclavicular joint. These models may also be useful for analyzing and assessing biomechanical stability after various types of surgical reconstruction.

Acromioclavicular Joint Injuries in Sport

ABSTRACT

Sport-related shoulder injuries, including disruptions to the acromioclavicular joint (ACJ), are common. An ACJ injury is classified by the degree and direction of the clavicle displacement. Although the diagnosis can be made clinically, standard radiographic views are important to determine the severity of the ACJ disruption and assess for concurrent injuries. The majority of ACJ injuries can be managed nonoperatively; however, surgical treatment is indicated in some cases. Long-term outcomes are generally favorable for most ACJ injuries, and athletes generally return to sport without functional limitations. This article provides an in-depth discussion regarding all aspects of ACJ injuries, including clinically relevant anatomy, biomechanics, evaluation, treatment, and complications.

The Reliability of Acromioclavicular Joint Dislocation Classification Systems: A Comparison Between the Rockwood and Kraus Classifications

Background

The Rockwood system for the classification of acute acromioclavicular (AC) joint dislocations has been associated with a lack of reliability. A novel system has been proposed (Kraus classification) that is based on dynamic posterior translation of these injuries.

Purpose

To assess the interobserver and intraobserver reliability of the Rockwood and Kraus classification systems and also to examine the impact of surgeon experience on the assessments.

Study Design

Cohort study (diagnosis); Level of evidence, 3.

Methods

Included were 45 patients with acute AC joint injuries who underwent a radiographic examination using standard bilateral AP and modified Alexander views. For interobserver reliability, 6 shoulder surgeons (expert group) and 6 orthopaedic residents (novice group) reviewed the radiographs to classify injuries according to the Rockwood and Kraus classifications; for each categorization, the participants chose between nonoperative management and surgical treatment. The evaluation was repeated 6 weeks later to determine intraobserver reliability. Kappa (κ) coefficients and their 95% CIs were used to compare interobserver and intraobserver reliability for each classification system according to assessor experience. Statistical differences were considered significant when the upper and lower boundaries of the 95% CI did not overlap.

Results

The overall interobserver agreement for diagnosis (both novice and expert groups) was moderate (κ = 0.52 [95% CI, 0.51-0.54]) for the Rockwood classification and substantial (κ = 0.62 [95% CI, 0.53-0.65]) for the Kraus classification; however, no significant differences were observed between the κ values. The overall interobserver agreement for treatment selection was substantial when using both the Rockwood (κ = 0.78 [95% CI, 0.72-0.81]) and Kraus (κ = 0.77 [95% CI, 0.66-0.87]) classifications. The overall intraobserver agreement for diagnosis was substantial using both the Rockwood (κ = 0.65 [95% CI, 0.61-0.67]) and Kraus (κ = 0.73 [95% CI, 0.69-0.75]) classifications. There were no significant differences between the novice and expert groups on any of the evaluations.

Conclusion

The Kraus system was slightly more reliable than the Rockwood system for classifying AC joint injuries both between assessor groups and overall. The level of surgeon experience had no impact on the evaluations.

Surgical management of acute, high-grade acromioclavicular joint separations: a systematic review

Background

While a number of treatment options exist for repair of acute, high-grade acromioclavicular joint (ACJ) separation, none have emerged as the standard of care. The purpose of this study was to systematically review the literature on surgical treatment of acute, high-grade (Rockwood grades III-V) ACJ separations in order to compare outcomes between direct fixation and tendon graft ligament reconstruction.

Methods

A systematic review of the literature evaluating outcomes for acute ACJ separation treatment with direct fixation or free biologic tendon graft reconstruction was performed. The following databases were examined: the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, PubMed (1980-2021), and Embase (1980-2021). Studies were included if they reported a mean time to surgery as <6 weeks, contained >10 patients with a minimum 1-year follow-up, and reported clinical or radiographic outcomes.

Results

A total of 52 studies met the inclusion criteria. Seven studies reported outcomes following tendon graft ligament reconstruction (n = 128 patients). There were multiple methods of direct fixation. Thirty-three studies utilized suture button constructs (n = 1138), 16 studies used hook plates (n = 567), 2 studies used coracoclavicular screws (n = 94), 2 studies used suture fixation (n = 93), 2 studies used suture anchor (n = 55), 2 studies used suture cerclage fixation (n = 87), 1 used single multistrand titanium cable (n = 24), and 1 used K wire (n = 11). The mean follow-up Constant scores ranged from 77.5 to 97.1 in the fixation group compared to 90.3-96.6 in the tendon graft group. The mean visual analog scale scores ranged from 0 to 4.5 in the fixation group and 0.1-1 in the tendon graft group. Net CC distance ranged from 17.5 to 3.6 mm in the fixation group and 7.4-4 mm in the tendon graft group. The revision rates ranged from 0.0% to 18.18% in the direct fixation group and 5.88%-17% in the tendon graft group.

Conclusion

Direct fixation and tendon graft reconstruction for management of acute, high-grade ACJ separations have similar patient subjective and radiographic outcomes, as well as complication and revision rates at a minimum 1-year follow-up.

Arthroscopic-Assisted Double-Bundle Coracoclavicular Ligament Reconstruction Using Cortical Fixation Buttons With Suture Tape Provides Superior Vertical Stability Than the Single-Bundle Reconstruction for Acute Acromioclavicular Joint Dislocation

PURPOSE

This study aimed to compare clinical and radiologic outcomes between single- and double-bundle arthroscopic-assisted coracoclavicular (CC) ligament reconstruction using cortical fixation buttons with suture tapes for acute acromioclavicular (AC) joint dislocation.

METHODS

Patients who underwent arthroscopic-assisted CC ligament reconstruction using cortical fixation buttons with suture tapes for acute AC joint dislocation from July 2014 to March 2019 were identified. This study included patients treated for acute AC joint dislocation within 2 weeks after an injury, with a Rockwood classification of III or V and at least 2 years of follow-up. Patients were divided into 2 groups based on the reconstruction technique: group I (single-bundle technique) and group II (double-bundle technique). The clinical outcomes were compared using the American Shoulder Elbow Surgeons (ASES) score, Constant score, and visual analog scale for pain score between the 2 groups. On the plain radiograph, the CC interval ratio (CCIR) was measured to evaluate maintenance of CC interval fixation. Postoperative complications, including reduction failure, were also documented.

RESULTS

Fifty-eight patients (26 in group I, 32 in group II) were enrolled. There were no significant differences in CCIR between the 2 groups preoperatively and 3 months postoperatively. However, the CCIR of group I was significantly greater than that of group II 6 months postoperatively (group I: 160.5% ± 48.5%, group II: 125.4% ± 38.9% at 6 months postoperatively, P = .01; group I: 164.0% ± 57.3%, group II: 123.2% ± 35.9% at the last visit, P = .01). Despite radiologic differences, the clinical outcomes demonstrated no significant differences between 2 the groups (ASES score: 93.5 ± 5.2 in group I, 94.4 ± 4.5 in group II, P = .54; Constant score: 92.9 ± 5.3 in group I, 94.8 ± 4.3 in group II, P = .16). Reduction failure occurred in 4 patients (15.3%) in group I and in 1 patient (3.2%) in group II (P = .16).

CONCLUSIONS

Arthroscopic-assisted double-bundle CC ligament reconstruction using cortical fixation buttons with suture tapes provided superior vertical stability than the single-bundle technique.

LEVEL OF EVIDENCE

Level III, retrospective comparative study.

Acromioclavicular joint suture button repair leads to coracoclavicular tunnel widening

PURPOSE

Biomechanical evaluation of three different suture button devices used in acromioclavicular joint repair and analysis of their effect on post-testing tunnel widening.

METHODS

Eighteen human shoulder girdles were assigned into three groups with a similar mean bone mineral density. Three different single-tunnel acromioclavicular repair devices were tested: (1) AC TightRope^® with FiberWire; (2) AC Dog Bone^™ Button with FiberTape; (3) Low Profile AC Repair System. Biomechanical testing was performed simulating the complex movement of the distal clavicle as follows. A vertical load of 80 N was applied continuously. The rotation of the clavicle about its long axis was set at 10° anterior and 30° posterior for 2500 cycles at 0.25 Hz. The horizontal translation of the clavicle was set at 6 mm medial and 6 mm lateral for 10,000 cycles at 1 Hz. The coracoclavicular distance was measured before and after testing. After testing, each sample underwent micro-CT analysis. Following 3D reconstruction, the area of the bone tunnels was measured at five defined cross sections.

RESULTS

In TightRope^® and Dog Bone^™ groups, all samples completed testing, whereas in the Low Profile group, three out of six samples showed system failure. The mean absolute difference of coracoclavicular distance after testing was significantly greater in the Low Profile group compared to TightRope^® and Dog Bone^™ groups (4.3 ± 1.3 mm vs 1.9 ± 0.7 mm vs 1.9 ± 0.8 mm; p = 0.001). Micro-CT analysis of the specimens demonstrated significant tunnel widening in the inferior clavicular and superior coracoid regions in all three groups (p < 0.05).

CONCLUSION

Significant tunnel widening can be observed for all devices and is primarily found in the inferior parts of the clavicle and superior parts of the coracoid. The Low Profile AC Repair System showed inferior biomechanical properties compared to the AC TightRope^® and AC Dog Bone^™ devices. Therefore, clinicians should carefully select the type of acromioclavicular repair device used and need to consider tunnel widening as a complication.

Arthroscopic-Assisted Coracoclavicular Stabilization With Anchorless Transosseous Double-Row Acromioclavicular Ligament Complex Repair: The Acute Acromioclavicular Joint Dislocation

The current concept procedures in the acute acromioclavicular joint dislocation should be divided into 2 types of structure restoration: those that provide coracoclavicular stabilization, which affects the primary healing of the coracoclavicular ligaments by vertically stabilizing the clavicle and coracoid in their anatomical positions, and those that attempt to repair the superior acromioclavicular ligament complex, which controls both horizontal and rotational stabilization. The acute acromioclavicular joint dislocation clinical outcome will be achieved if you perform both procedures. It's difficult to stabilize the acromioclavicular joint in both vertical and horizontal planes, and most current techniques aren't always effective. In this Technical Note, we discuss an arthroscopic-assisted technique that reconstructs the coracoclavicular and acromioclavicular ligaments under image intensifier guidance to achieve bidirectional (vertical and horizontal) and rotational stability.

Clinical Outcomes of Arthroscopy-Assisted Modified Triple Endobutton Plate Fixation in Rockwood Type III Acute Acromioclavicular Joint Dislocation: A Retrospective Study

Objective

The common triple Endobutton plate (CTEP) fixation is a lengthy procedure that is associated with high failure rates. Therefore, we used arthroscopy to improve the Endobutton fixation method by shortening the duration of surgery and reducing operative complications. This study explored the safety and effectiveness of arthroscopy‐assisted modified triple Endobutton plate (MTEP) fixation in Rockwood type III managing acute acromioclavicular joint (ACJ) dislocation.

Methods

This was a retrospective single‐center study involving 73 patients with Rockwood type III acute ACJ dislocation treated between January 2016 and January 2021. The 73 patients were classified into three groups, the acromioclavicular hook plate (ACHP) group (22 cases), CTEP group (24 cases) and MTEP group (27 cases), based on the type of surgical treatment they received. Clinical outcome data from the patient records, including the Constant–Murley score (CMS), American Shoulder and Elbow Surgeons score (ASES) and University of California at Los Angeles shoulder rating scale score (UCLA), were retrospectively reviewed. The scores were assessed before surgery and at the third and twelfth month after surgery. The clavicle‐coracoid (CC) distance on the affected side was estimated from imaging scans taken before surgery, on the second day after surgery, and within the third and twelfth month after surgery. The student's t‐test was used to compare normally distributed data for independent samples, while homogeneity of variance test was used to compare normally distributed data among multiple groups. Non‐normally distributed data were compared using Mann–Whitney rank‐sum tests.

Results

There were no differences in age, gender, body mass index (BMI), dislocated side, trauma etiology, and duration of follow‐up among the three groups. There was also no significant difference in the duration of surgery between the ACHP and MTEP groups, although the duration in the two groups was shorter than in the CTEP group (P < 0.05). The duration of hospitalization for the MTEP group was significantly shorter than for the CTEP group which was in turn shorter than for the ACHP group (both P < 0.05). There was no significant difference in postoperative CMS, ASES, and UCLA scores between the CTEP and MTEP groups but the score for the two groups differed significantly from those of the ACHP group (all Ps < 0.05). In addition, there was no significant difference in CC distance among the three groups after surgery (P > 0.05).

Conclusion

Arthroscopic reconstruction of the coracoclavicular ligament using MTEP fixation to manage acute Rockwood type III ACJ dislocation is minimally invasive, and is associated with rapid functional recovery, few complications and satisfactory early clinical results.

Combination of Surgical Techniques Restores Multidirectional Biomechanical Stability of Acromioclavicular Joint

PURPOSE

To measure the multiaxial stability of the acromioclavicular joint before and after transection of the acromioclavicular capsule and coracoclavicular ligaments and after sequential repair of acromioclavicular and coracoclavicular ligaments.

METHODS

Biomechanical testing was performed on fresh-frozen human cadaveric shoulders (N = 6). Translational and rotational stability in the vertical and horizontal planes was measured in intact specimens, after transecting the acromioclavicular and coracoclavicular ligaments, and after sequentially performing the following procedures: single-bundle coracoclavicular repair (CCR), modified Weaver-Dunn procedure (WD), and acromioclavicular stabilization (ACS).

RESULTS

Resecting the acromioclavicular and coracoclavicular significantly reduced translational stiffness in the inferior and anteroposterior directions, as well as rotational stiffness about the vertical and anteroposterior axes. All 3 surgical procedures increased inferior translational stiffness relative to the intact condition (Intact: 38 ± 9 N/mm, CCR: 54 ± 23 N/mm (P = .03), CCR+WD 52 ± 20 N/mm (P = .07), CCR ± WD+ACS 50 ± 21 N/mm (P = .17)). However, the combination of CCR, modified WD, and ACS resulted in the greatest increase in stiffness in internal rotation (Intact: 12.5 ± 7.4 cNm/deg, CCR: 1.2 ± 1.1 cNm/deg, CCR+WD 7.2 ± 3.0 N∗m/deg [P = .023], CCR+WD+ACS 11.6 ± 4.9 cNm/deg [P = .055]).

CONCLUSIONS

The cumulative stability of CCR, WD reconstruction, and ACS appears to be additive. Our findings provide a biomechanical justification for combining all three techniques. Biomechanical studies assessing the performance of various acromioclavicular repairs and reconstructions should therefore incorporate multiaxial testing in their protocols.

CLINICAL RELEVANCE

Multiple points of fixation that provide multidirectional stability have the potential to improve clinical outcomes and reduce failure rates of acromioclavicular joint repair or stabilization.

Arthroscopically assisted single tunnel reconstruction for acute high-grade acromioclavicular joint dislocation with an additional acromioclavicular joint cerclage

PURPOSE

Purpose of this study was to demonstrate that a single tunnel reconstruction of high-grade acromioclavicular (AC) joint instabilities with implants of the second generation is sufficient for stabilisation, especially in combination with an AC cerclage.

METHODS

Patients with an acute AC-joint dislocation type Rockwood III-B and V were included. Besides clinical follow-up examination, radiographs were analysed. The functional outcome measures were Constant Score (CS), Taft score (TS), ACJI score and patient's satisfaction. Horizontal instability was evaluated by clinical examination and radiological with an Alexander view.

RESULTS

Thirty-five patients with a mean follow-up of 29 months were included. Ninety-seven per cent were satisfied with their result, with an average Subjective Shoulder Value of 90%. The CS averaged at 90 ± 10 points, TS at 11 ± 1 points and ACJI at 78 ± 18 points. Radiologically, 3 of 29 patients (10%) showed a persisting horizontal instability. The coracoclavicular (CC) distance improved from 22 preoperative to 10 mm postoperative, which was comparable to the contralateral side (10 mm, p = 0.103). At follow-up the CC distance increased to 13 mm (p = 0.0001).

CONCLUSION

AC-joint stabilisation with a single tunnel reconstruction using a second-generation implant results in good to excellent clinical results with high patient satisfaction. The additional AC augmentation improves stability in horizontal instable AC-joints and is recommended in all high-grade AC joint stabilisations. Nonetheless, reduction was slightly lost over time due to an elongation or suture failure of the coraco-clavicular fixation.

LEVEL OF EVIDENCE

IV.

Truly anatomic coracoclavicular ligament reconstruction with 2 EndoButton devices for acute Rockwood type V acromioclavicular joint dislocations: 5-year findings

BACKGROUND

To date, mid-term clinical and radiologic outcomes of treatment for acute Rockwood type V acromioclavicular (AC) joint dislocations using 2 EndoButton devices (Smith & Nephew, Andover, MA, USA) have not been reported in the literature.

METHODS

We reviewed 25 patients (15 men and 10 women) with acute AC joint separations who were treated with truly anatomic coracoclavicular ligament reconstruction using 2 EndoButton devices between May 2013 and October 2015. Clinical assessments consisted of the visual analog scale score and the Constant score. Radiologic evaluation was achieved by measuring the coracoclavicular distance and AC distance. Previously, this same patient cohort was reviewed after 2 years of follow-up using similar methods.

RESULTS

All 25 patients were available for mid-term follow-up 5 years after the operation. The mean duration of follow-up was 76 ± 7 months (range, 66-90 months). Of the patients, 23 (92%) continued to be satisfied or very satisfied with the treatment results. The visual analog scale score and Constant score improved significantly when compared with the baseline scores (0 ± 0 and 96 ± 3, respectively, at 5-year follow-up vs. 5 ± 1 and 45 ± 6, respectively, postoperatively) and remained essentially unchanged when compared with the 2-year follow-up data (0 ± 0 and 96 ± 3, respectively, at 5-year follow-up vs. 0 ± 1 and 95 ± 3, respectively, at 2-year follow-up). On the 5-year radiographs, 3 patients (12%) demonstrated loss of reduction and 5 patients (20%) had calcifications noted. There was, however, no significant difference in clinical outcomes or patient satisfaction when comparing patients with radiographically abnormal findings vs. patients with anatomic reduction.

CONCLUSION

Truly anatomic coracoclavicular ligament reconstruction using 2 EndoButton devices results in satisfactory functional outcomes at 5 years postoperatively. In contrast to baseline, all cases improved significantly.

Single tunnel technique versus coracoid sling technique for arthroscopic treatment of acute acromioclavicular joint dislocation

To evaluate and compare the efficacy of two techniques for the treatment of acute acromioclavicular joint dislocation, the charts of 60 patients diagnosed with acute Rockwood type IV and V acromioclavicular joint dislocation that undergone arthroscopic fixation procedure with single tunnel technique (N = 30, 30.7 ± 5.7 years old) or coracoid sling technique (N = 30, 30.1 ± 5.4 years old) fixation were retrospectively reviewed. The Visual Analog Scale pain score, Constant shoulder functionality score, Karlsson acromioclavicular joint score, the time of return to sports and activity, and plain radiographs of the affected shoulder at different time points of follow-up were recorded for a minimum of 2 years post-op. The majority of the patients recovered to their preoperative activity levels with few complications. The average postoperative acromioclavicular and coracoclavicular distances were significantly narrower than preoperative measurements in both groups without significant difference between the two groups at 2 years post-op (P < 0.05). The coracoid sling technique group had reduced operative time, shorter time of recovery of shoulder movements, higher Constant functionality scores and Karlsson acromioclavicular joint scores, and fewer complications than the single tunnel technique group at the last follow-up (P < 0.05). Therefore, coracoid sling technique achieved superior clinical outcomes with fewer complications compared to the traditional single tunnel technique in arthroscopic treatment of acute acromioclavicular joint dislocation.

Combination of Clavicular Hook Plate with Coracoacromial Ligament Transposition in Treatment of Acromioclavicular Joint Dislocation

OBJECTIVE

To evaluate the clinical efficacy of Arbeitsgemeinschaft für Osteosynthesefragen (AO) clavicular hook plate (CHP) combined with coracoacromial ligament transposition for Rockwood III-V dislocation of AC joint, providing an alternative choice for AC joint dislocation treatment.

METHODS

Twenty-five patients diagnosed with Rockwood III-V dislocation of acromioclavicular (AC) joint, including 18 males and seven females, aged 43.5 ± 2.4 years old on average, who had undergone open reduction and AO CHP in combination with coracoacromial (CC) ligament transposition between January 2010 and December 2015, were retrospectively analyzed. Among them, 17 cases were diagnosed as type III, five cases were type IV, and three cases were type V. The surgery mainly included three main steps: bone flap incision, drilling in the clavicle, and hook plate fixation and AC joint reposition. The treatment efficacy was evaluated through clinical examinations and imaging studies for the shoulder joint, including gross observation and measuring coracoid clavicle distance (CC-Dist) using orthophoria X-ray before and 1 year after the surgery, and University of California (UCLA) shoulder rating scale.

RESULTS

All the patients were followed up three to four times in 18 months (12-24 months) on average, and the UCLA rating results showed that there were 17 excellent cases (68%), five good cases (20%), and three fair cases (12%). The CC-Dist values after the surgery reduced to 9.7 ± 0.7 mm, which was significantly (P < 0.05) lower compared to that before the surgery (15.8 ± 1.6 mm). Most (88%) of the cases showed almost normal joint function and good anatomical arrangement of the acromioclavicular joint, without any secondary dislocation, and for them, 12 ± 2 weeks on average were needed to regain the normal function of shoulder joint movement.

CONCLUSION

Due to the stable fixation, fewer complications, and satisfactory therapeutic effect with great clinical value, the combination of AO CHP and CC ligament transposition is expected to be used for treating Rockwood III-V dislocation of AC joint.

A biomechanical in-vitro study on an alternative fixation technique of the pubic symphysis for open book injuries of the pelvis

PURPOSE

Implant failure rates remain high after plate fixation in pelvic ring injuries. The aim of this study was to compare an alternative fixation technique with suture-button devices and anterior plate fixation in partially stable open-book injuries.

MATERIAL AND METHODS

We acquired 16 human fresh frozen anatomic pelvic specimens. The sacrospinous, sacrotuberous, and anterior sacroiliac ligaments were bilaterally released, and the pubic symphysis transected to simulate a partially stable open-book (AO/OTA 61-B3.1) injury. The specimens were randomly assigned to the two fixation groups. In the first group two suture-button devices were placed in a criss-crossed position through the symphysis. In second group a six-hole plate with standard 3.5 unlocked bicortical screws was used for fixation. Biomechanical testing was performed on a servo-hydraulic apparatus simulating bilateral stance, as described by Hearn and Varga. Cyclic compression loading with a progressively increasing peak load (0.5 N/cycle) was applied until failure. The failure mode, the load and the number of cycles at failure and the proximal and distal distance of the symphysis during testing were compared.

RESULTS

There was no implant failure in either of the two groups. Failures occurred in nine pelvises (56.2%) at the fixation between the sacrum and the mounting jig and in seven pelvises (43.8%) in the sacroiliac joint. Neither the ultimate load nor the number of cycles at failure differed between the surgical techniques (p = 0.772; p = 0.788, respectively). In the suture button group the mean ultimate load was 874.5 N and the number of cycles at failure was 1907.9. In the plate group values were 826.1 N and 1805.6 cycles, respectively. No significant differences at proximal and distal diastasis of the symphysis were monitored during the whole loading process.

CONCLUSION

The fixation with suture button implants showed comparable results to anterior plate fixation in open-book injuries of the pelvis.

Failure of Acromioclavicular Joint Reconstruction Eight Weeks After Hook Plate Removal: A Case Report

A female patient who underwent successful reconstruction of an acute high-grade acromioclavicular (AC) joint separation with hook plate presented with failure of the reduction eight weeks after removal of the hardware. Surgeons and patients should be aware of the risk of late failure of acromioclavicular reconstruction after removal of the hook plate.

The Kite technique: a new all-arthroscopic technique for the treatment of acute acromioclavicular joint dislocation

PURPOSE

Although many open techniques have been developed, no all-arthroscopic technique has been introduced to reduce acute acromioclavicular joint dislocation (ACJD) and augment both coracoclavicular (CC) ligaments. The Kite technique is the first all arthroscopic technique with this aim.

METHODS

Forty-one consecutive patients [35M-6F; median: 29.2 years (range 23-36)] with acute type III and V acromioclavicular joint dislocation were treated with the Kite technique: it consists of positioning three titanium buttons connected by heavy sutures in an 8-strand configuration between clavicle and coracoid to restore the anatomy of CC ligaments. Patients were followed up for a median of 35 months (range 30-43 months).

RESULTS

Median operation time was 70.6 min (range 58-82), with no cases of intra-operative complications. At the final follow-up, the median post-operative Constant Score and SST were 94.1 (range 89-98) and 11.6 (range 10-12), respectively. At the final follow-up reduction maintenance was present in 39 patients; in one patient, signs of acromioclavicular joint dislocation recurrence were present 3 months post-op. In another patient, medial suture ruptures occurred 4 months after surgery with type II acromioclavicular joint dislocation recurrence but with scarce symptoms and full recovery to sport activity. Clavicle osteolysis was observed in four patients. Cosmetics of the arm were judged as excellent in 39/41. All patients, except two, were satisfied with the final result.

CONCLUSIONS

The kite technique is a safe and reproducible arthroscopic procedure to treat acute ACJD. In daily clinical practice, due to the excellent results and the low complication rate, this technique might be considered by surgeons when operative treatment of an acute acromioclavicular joint dislocation is planned.

LEVEL OF EVIDENCE

IV.

The prevalence of intraarticular associated lesions after acute acromioclavicular joint injuries is 20%. A systematic review and meta-analysis

PURPOSE

To synthesise the evidence on the prevalence of associated intraarticular lesions in subjects with acute acromioclavicular joint (ACJ) dislocations.

METHODS

A search in two electronic databases (PUMBMED and EMBASE) was performed from 1985 to 2019. Two independent reviewers selected studies that complied with the following inclusion criteria: (1) the study included data on surgically treated ACJ dislocation grade III-V in the Rockwood classification, (2) the ACJ injuries were acute (the surgery was performed less than 6 weeks after injury), (3) an arthroscopic evaluation of the glenohumeral joint was performed during surgery. The quality of the studies included was assessed using the tool of the Joanna Briggs Institute.

RESULTS

A total of 47 studies with acute ACJ injuries met the initial inclusion criteria. Of these, 21 studies (9 retrospective case series, 9 prospective case series and 3 retrospective cohort studies) presented data on associated intraarticular lesions amenable for use in the meta-analysis. The meta-analysed studies included a total of 860 subjects with acute ACJ dislocations with a male/female ratio of 6.5 and a mean age of 32 years. The meta-analysis showed a prevalence of associated intraarticular lesions in subjects with acute ACJ of 19.9% (95% confidence interval [CI] 14.0-26.4%; 21 studies, 860 analysed participants; P = 0.000; I²: 74.5% random-effects model; low risk of bias).

CONCLUSION

One in five subjects with surgically treated acute ACJ dislocations will have an associated intraarticular lesion that requires further intervention. The case for a customary arthroscopic evaluation of the joint, even when an open procedure is performed to deal with the ACJ dislocation, is strong. Level of evidence IV Trial registry Systematic review registration number: PROSPERO CRD42018090609.

Biologic and synthetic ligament reconstructions achieve better functional scores compared to osteosynthesis in the treatment of acute acromioclavicular joint dislocation

PURPOSE

To systematically review the outcomes of surgical treatments of acute acromioclavicular joint dislocation.

METHODS

Studies were identified by electronic databases (Ovid, PubMed). All studies reporting functional and radiological outcomes of surgical treatments of acute acromioclavicular joint dislocations were included. Following data were extracted: authors and year, study design, level of evidence, number of patients, age, classification of acromioclavicular joint dislocation, time to surgery, surgical technique, follow-up, clinical and imaging outcomes, complications, and failures. Descriptive statistics was used, when a data pooling was not possible. Comparable outcomes were pooled to generate summary outcomes reported as frequency-weighted values. Quality appraisal was assessed through the MINORS checklist.

RESULTS

One hundred and thirty-three studies were included for a total of 4473 shoulders. Mean age of participants was 36.9 years. Mean follow-up was 42.06 months. Arthroscopy showed better ASES (p < 0.0001) and lower VAS pain score (p = 0.0249) compared to an open approach. Biologic and synthetic reconstructions demonstrated better results over osteosynthesis techniques. Biologic techniques showed overall better Constant (p = 0.0001) and DASH (p = 0.0215) scores, while synthetic reconstruction showed better UCLA score (p = 0.0001). Among suture buttons, triple button showed overall better results in Constant (p = 0.0001) and VAS (p = 0.0001) scores, while better results in DASH score (p = 0.0003) were achieved by 2 double button techniques. Overall, the level of evidence was low.

CONCLUSION

Biological and synthetic reconstructions achieved better functional scores compared to osteosynthesis. Among suture buttons, the triple button showed better functional performance.

LEVEL OF EVIDENCE

IV.

Clinical outcomes of arthroscopic and navigation-assisted two tunnel technique for coracoclavicular ligament augmentation of acute acromioclavicular joint dislocations

Background

The purpose of this study was to present a navigated image-free augmentation technique for the acromioclavicular joint (ACJ) and coracoclavicular (CC) ligaments and to report the clinical and radiological outcomes.

Methods

From 2013 to 2018, 35 eligible patients were treated with our navigated image-free ACJ- and CC-augmentation technique. The average follow-up was 3 years. Follow-up evaluations included the Constant-Murley Score, subjective shoulder value, Taft score, and the acromioclavicular joint instability (ACJI) score. The patients’ quality of life was assessed using the EuroQol-5D (EQ-5D) questionnaire. In addition, in accordance with the instability criteria, radiographs were evaluated before surgery, after surgery, and during follow-up.

Results

Overall, 25 patients (71%) suffered an acute type V disruption, 5 (14%) had a type IV disruption, and 5 (14%) had an acute Rockwood type IIIb injury. The mean Constant-Murley Score was 90 (range: 56–100; p = 0.53) on the injured side, and the mean subjective shoulder value was 92% (range: 80–100%). The mean Taft and ACJI scores were 10 (range: 4–12) and 86 (range: 34–100), respectively and the mean EQ-5D was 86 (range: 2–100). The mean CC difference of the injured side was 4 mm (range: 1.9–9.1 mm) at follow-up, which was not significantly different than that of the healthy side (p = 0.06). No fractures in the area of the clavicle or the coracoid were reported.

Conclusions

The arthroscopic- and navigation-assisted treatment of high-grade ACJ injuries in an anatomical double-tunnel configuration yields similar clinical and radiological outcomes as the conventional technique using an aiming device. Precise positioning of the navigation system prevents multiple drillings, which avoids fractures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04406-2.

Comparison of the TightRope system versus hook plate in acute acromioclavicular joint dislocations: a retrospective analysis

This study compared the results of the minimally invasive coracoclavicular (CC) fixation with a single TightRope (MITR) procedure and the hook plate (HP) procedure for acute acromioclavicular (AC) joint dislocation treatment. Sixteen patients with a mean age of 44.9 ± 11 years were treated with the MITR procedure. Nineteen patients with a mean age of 40.2 ± 8.7 years were treated using the HP procedure. Clinical outcomes were evaluated with the Visual Analog Scale (VAS) for pain, Constant–Murley Score (CMS), and University of California at Los Angeles (UCLA) Shoulder score. Vertical displacement of the clavicle with reference to the height of the acromion was measured in standard anteroposterior radiographs. The mean follow-up was 27 months in the MITR group and 30 months in the HP group. No statistically significant differences were found between the MITR group and the HR group in terms of VAS score (0.4 ± 0.6 vs 0.7 ± 0.6, P = 0.138), UCLA Shoulder score (33.9 ± 2.5 vs 33.7 ± 1.5, P = 0.843), or CMS (95.7 ± 7.3 vs 93.7 ± 6.6, P = 0.400). No redislocation was identified in the HP group, while redislocation occurred in 1 of 16 (6.3%) patients in the MITR group. One patient in the HP group (5.3%) had acromial osteolysis, while no acromial osteolysis was found in the MITR group. No other adverse events, such as infections, tunnel widening, fractures, or implant-related complications, were observed. Both procedures provided satisfactory results. The HP procedure provided better reduction, while the MITR procedure provided a slightly lower tendency of pain. Long-term follow-up is needed to investigate the clinical outcomes and radiological outcomes of both groups.

Acromioclavicular joint separation treated with clavicular hook plate: a study of radiological and functional outcomes

INTRODUCTION

ACJ separation is a common shoulder injury. A variety of surgical techniques for high-grade ACJ separations have been described. A commonly used technique represents open reduction and fixation by a hook plate. Goal of the present study was to evaluate radiographic and functional outcome in patients with high-grade ACJ separations following surgical treatment with a hook plate before and after surgery as well as after hook plate removal.

MATERIALS AND METHODS

Patients undergoing surgery with a hook plate due to traumatic ACJ separation between 2012 and 2014 were included and examined during a follow-up control. Demographic and clinical data as well as radiographs pre- and postoperatively were evaluated. Additionally, range of motion, DASH Score and Constant-Murley Score (CMS) were analysed in a follow-up examination. Wilcoxon signed-rank test and Spearman's rank correlation were used for statistical analysis.

RESULTS

99 patients (88 m/11 w, 44 y) were included in the present study. 69 (64 m/5 w, 49 y) could be examined during long-term follow-up (38 month). After hook plate removal, the CCD increased significantly (13.7 ± 0.9 mm) compared to the hook plate in situ (9.9 ± 0.8 mm, p = 0.000001). 68% of all patients achieved a full range of motion post-operatively. Main limitations of range of motion affected external rotation as well as ante-/retroversion. Mean DASH Score was 5.6 ± 1 points and CMS 90.0 ± 1.4 points.

CONCLUSION

In contrast to a significant higher CCD after hook plate removal, nearly all patients achieved good to excellent functional results for DASH and CMS. This indicates that loss of reduction does not necessarily lead to poor functional outcome after ACJ separation surgery.

BiPOD arthroscopically assisted bidirectional stabilisation technique for high-grade acromioclavicular joint injury: two-year clinical and radiological outcomes

PURPOSE

The purpose of this study was to evaluate the intermediate-term clinical and radiological outcomes for acute, unstable acromioclavicular joint (ACJ) injuries treated with the arthroscopically assisted BiPOD stabilisation technique.

METHODS

Twenty-three patients who sustained acute, unstable ACJ injuries were included in this prospective study. We recorded demographics, injury classification, time to surgery, clinical scores, radiological outcomes and complications; each patient completed a minimum of 2 years post-operative observation.

RESULTS

Mean follow-up was 26 months (range, 24-34). Clinical outcomes scores demonstrated good 2-year results: relative Constant score, 97.9/100; ACJ Index, 89.4/100; Subjective Shoulder Value, 92.4/100 and Taft = 11.1/12. Final C-C distance showed a mean of 0.7 mm (SD ± 1.8 mm) at 2 years. Complication rate was 9%.

CONCLUSION

The BiPOD technique shows excellent, reliable intermediate-term results with a favourable complication rate compared to existing techniques; it provides a comprehensive surgical option for the stabilisation of acute ACJ injuries restoring both vertical and horizontal stability.

Treatment of acromioclavicular joint separations in Japan: a survey

Background

Treatment options for acromioclavicular joint (ACJ) separations are highly dependent on severity, as well as the patient’s background. Furthermore, some patients can be switched from conservative to surgical treatment. In this study, we conducted a mail-based questionnaire survey of members of the Japan Shoulder Society on the administration of treatments for ACJ separations.

Methods

A questionnaire survey with 5 categories was mailed to all 1655 members of the Japan Shoulder Society (including 59 councilors): initial treatment, whether surgery was performed, indications for surgery based on severity, switching from conservative to surgical treatment, and surgical methods.

Results

Altogether, 183 members, including 56 councilors, responded. Regarding the initial treatment, 17 respondents opted for treatment without immobilization or fixation and 166 opted for immobilization or fixation. Of the members, 11 opted for only conservative treatment whereas 172 chose surgery depending on the case; of the latter, 9 considered it for patients with a Rockwood classification of type 2 or higher; 120, for patients with type 3 or higher; and 172, for patients with types 4-6. Furthermore, 75 of 172 members had experience switching to surgical treatment during conservative treatment. For 64 of 172 members, the modified Cadenat method was the most common surgical method.

Conclusions

Only 11 members opted for conservative treatment of ACJ separations, and approximately 95% of physicians chose surgery. Furthermore, >70% of physicians considered surgery for an injury classified as type 3 or higher, and 37% of members performed the modified Cadenat method. However, the popularization of arthroscopic surgery may affect the selection of surgical methods in the future.

RR, Costa G, Verdalet I, Ezzeddine H, Rius X. Arthroscopically Assisted Comprehensive Double Cerclage Suture Fixation Technique for Acute Acromioclavicular Joint Separation

Acromioclavicular dislocations are some of the most frequently recorded and controversial injuries in the athletic population. These injuries have historically been a matter of disagreement between surgeons, particularly when it comes to the surgical technique used to treat them, its approach, or its timing. Consensus over the "gold standard" procedure to treat them is yet to be established. Even though numerous surgical techniques have already been described, the number of complications and loss of reduction remains a matter of concern for treating physicians. Here, we present an arthroscopically assisted coracoclavicular and horizontal acromioclavicular fixation technique in a modified figure-of-eight configuration using 2 strong FiberTape Cerclage sutures, with measurable tension, for the comprehensive treatment of acromioclavicular joint dislocations.

TightRope vs Clavicular Hook Plate for Rockwood III-V Acromioclavicular Dislocations: A Meta-Analysis

Objective

To assess and compare the clinical outcomes and complications of TightRope® fixation vs hook plate fixation for the treatment of Rockwood III‐VI Acromioclavicular joint (ACJ) dislocations.

Methods

Relevant studies were identified by searching PubMed, Embase, and Web of Science databases, from their inception to 12 April, 2019. The main outcomes of interest included Constant Score, University of California Los Angeles (UCLA) Shoulder Score, Visual Analogue Scale (VAS), coracoclavicular distance (CCD), and complications. Weight mean difference (WMD) with 95% confidence intervals (95% CIs) or risk ratio (RR) with 95% CIs was used to calculate the data.

Results

Four studies with a total of 179 patients were included in this study. Compared with hook plate, TightRope® fixation was associated with a significantly less VAS score for pain (WMD = ‐0.69, 95% CI: −1.10, −0.27; P = 0.001). However, there were no significant differences between the two surgical techniques in terms of Constant Score (WMD = 6.12, 95% CI: −3.84, 16.08; P = 0.229), UCLA (WMD = 7.96, 95% CI: −5.76, 21.68; P = 0.256), CCD (WMD = 0.24, 95% CI: −0.67, 1.15; P = 0.602), and complication rate.

Conclusion

Both TightRope® and hook plate techniques offered effective outcomes in relieving the pain of dislocation and improving function of ACJ. However, TightRope® fixation showed an advantage over hook plate in terms of postoperative pain. Further larger‐scale RCTs are needed to verify our findings.

Systematic review of the treatment of acromioclavicular joint disruption comparing number of tunnels and graft type

BACKGROUND

The management of high-grade acromioclavicular separations remains unclear. The surgical interventions have shifted to more anatomic, less invasive techniques. The purpose of this study was to systematically review the outcomes and complications of anatomic coracoclavicular ligament reconstruction using a tendon graft.

METHODS

Twenty-one studies (n = 460 patients) met the criteria for inclusion. A double clavicle tunnel tendon graft construct was used in 348 patients (75.7%), whereas a single clavicle tunnel technique was used in 112 patients (24.3%). No significant difference in loss of reduction was found between the 2 techniques. Of 460 patients, 96 (20.9%) demonstrated some form of radiographic displacement at the final follow-up. The overall complication rate was 21.3% (98 of 460), and a higher complication rate was found in the double clavicle tunnel technique (P < .001). The overall reoperation rate was 7.6% (37 of 460). The most common reason for reoperation was clavicle fracture (8 of 37). There was a statistically significant increase in reoperation when allograft was used (P = .003).

CONCLUSION

The results of this study suggest that despite newer techniques, approximately 20% of patients develop loss of reduction and/or experience a surgical complication. Attempts to minimize trauma to the clavicle and use autograft tendon may reduce the risk of reoperation.

Vertical and Rotational Stiffness of Coracoclavicular Ligament Reconstruction: A Biomechanical Study of 3 Different Techniques

PURPOSE

To compare the biomechanical stability of 3 different coracoclavicular reconstruction techniques under rotational and vertical loading using a cadaveric model.

METHODS

In total, 12 cadaveric shoulders were used for testing. The native state was first tested then followed by 3 different reconstruction configurations using suture tapes and cortical buttons: coracoid loop (CL), single-bundle (SB), and double-bundle (DB). Superior displacement was measured by cycling an inferiorly directed force of 70 N to the scapula. The rotational stiffness of the scapula was determined by cycling the scapula in rotational displacement control between 15° of internal and external rotation. The rotational stiffness of the clavicle was determined by rotating the clavicle around its long axis 20° anteriorly and 30° posteriorly in rotational displacement control. All measurements were captured over 10 cycles at a rate of 200 Hz.

RESULTS

Both the CL and SB techniques demonstrated significantly less internal scapular rotation stiffness. (intact: 19.70 ± 9.07 cNm/deg, CL: 3.70 ± 2.63 cNm/deg, SB:4.30 ± 2.66 cNm/deg, P <.001) External scapular rotation stiffness was significantly decreased in all techniques (intact: 17.70 ± 4.43 cNm/deg, CL: 3.30 ± 1.37 cNm/deg, SB: 4.50 ± 1.56 cNm/deg, DB: 4.67 ± 1.99 cNm/deg, P < .001). The CL and SB reconstructions were significantly less stiff with regards to posterior rotation of the clavicle (intact: 5.60 ± 1.80 cNm/deg, CL: 2.90 ± 1.10 cNm/deg, SB: 1.40 ± 0.65 cNm/deg, P < .001). Anterior rotation stiffness of the clavicle was significantly lower in all of the reconstructions (intact: 6.95 ± 1.90 cNm/deg, CL: 3.08 ± 0.84 cNm/deg, SB: 3.64 ± 0.93 cNm/deg, DB: 4.48 ± 1.21 cNm/deg, P < .001).

CONCLUSIONS

None of the described techniques provided equivalent rotational stability in all planes compared with the native state. DB reconstruction presented stiffness characteristics closest to the native state under cyclic loading during internal scapular and posterior clavicular rotation.

CLINICAL RELEVANCE

Additional procedures such as tendon grafting or acromioclavicular ligament reconstruction may be required to control rotational stability.

Recurrent acromioclavicular joint dislocation with an associated coracoid fracture following acromioclavicular joint reconstruction

Acromioclavicular joint injuries are common and account for up to 12% of all shoulder girdle injuries and have been reported as being as high as 50% in sports-related shoulder injuries. While the majority of acromioclavicular joint dislocations can be treated non-operatively, there are certain injury configurations, which can include high-grade dislocations in overhead athletes, where surgery may be indicated. The surgical management of acromioclavicular joint instability has moved towards recreating the action of the coracoclavicular ligaments by resuspending the clavicle on to the coracoid. Multiple techniques using high-strength sutures, synthetic ligaments, tendon allografts or autografts passed either around or through the coracoid process have been described. However, an unusual, but significant, complication associated with these techniques is an iatrogenic fracture of the coracoid process. We report the case of a patient with an iatrogenic coracoid fracture following two failed acromioclavicular joint resuspensory reconstructions using a synthetic ligament. This injury was successfully treated with an autologous hamstring graft reconstruction, initially protected with a hook plate.

Suture Button Versus Hook Plate for Acute Unstable Acromioclavicular Joint Dislocation: A Meta-analysis

BACKGROUND

Surgical treatment is indicated for unstable acromioclavicular (AC) joint dislocation. The hook plate (HP) technique is a commonly used treatment method, but the use of the suture button (SB) technique is increasing.

PURPOSE

To conduct a meta-analysis of clinical studies evaluating patient outcomes between the SB and HP techniques for acute unstable AC joint dislocation.

STUDY DESIGN

Meta-analysis.

METHODS

A literature search of the Embase, PubMed, and Cochrane Library databases was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Cohort studies and case-control studies comparing the SB and HP procedures for acute unstable AC joint dislocation were included. Statistical analysis was performed with RevMan (v 5.3.5).

RESULTS

Eight clinical studies that met the inclusion criteria were identified and included a total of 204 patients treated with the SB technique and 195 patients with the HP technique. Patients treated with the SB technique had a higher Constant score (mean difference [MD], 3.95; 95% CI, 1.20-6.70; P = .005) and a lower visual analog scale pain score (MD, -0.75; 95% CI, -1.12 to 0.37; P < .0001) when compared with the HP technique. No significant differences in operation time (MD, -0.38; 95% CI, -7.14 to 6.37; P = .91), coracoclavicular distance (MD, -0.07; 95% CI, -0.49 to 0.35; P = .75), complications (odds ratio, 0.59; 95% CI, 0.22-1.54; P = .28), and loss of reduction (odds ratio, 2.55; 95% CI, 0.66-9.83; P = .17) were found between the SB and HP techniques. The subgroup analysis showed that the arthroscopic SB technique resulted in a higher Constant score (MD, 6.75; 95% CI, 4.21-9.29; P < .00001) as compared with the HP technique, but no differences were observed between the open SB and HP techniques (MD, 0.69; 95% CI, -0.82 to 2.20; P = .37).

CONCLUSION

This meta-analysis demonstrated that the SB technique resulted in better functional outcomes and a reduced visual analog scale pain score when compared with the HP technique. However, for operation time, coracoclavicular distance, complications, and loss of reduction, there were no statistically significant differences between the techniques. Compared with the open procedure, arthroscopic SB may be superior for better functional outcomes.

Radiographic displacement of acute acromioclavicular joint dislocations fixed with AC TightRope

Background

The arthroscopic approach to acromioclavicular (AC) dislocation with methods such as AC TightRope fixation has reported radiographic failure rates between 18% and 50% with functional results graded as good or excellent. Our objective was to review the outcomes after arthroscopic fixation for acute AC joint dislocation using the TightRope device.

Methods

We reviewed the records of 52 patients, with a mean age of 31 years, who underwent arthroscopic fixation with the TightRope device for acute AC joint dislocation. Outcomes were evaluated using the Constant and University of California, Los Angeles scores. The coracoclavicular (CC) distance before and after surgery was compared by radiography.

Results

The mean follow-up period was 36.7 months (range, 6-65 months). Postoperatively, the mean Constant score was 97.13 and the mean University of California, Los Angeles score was 33.2. The CC distance was maintained in 73% of the patients, whereas partial loss of reduction occurred in 19.2% and failure of reduction occurred in 7.7%.

Conclusion

Arthroscopic fixation using the TightRope device for acute AC joint dislocation achieves satisfactory clinical outcomes. However, CC reconstruction appears to result in subluxation in cases with AC dislocation for a period of more than 10 days.

Repair of the entire superior acromioclavicular ligament complex best restores posterior translation and rotational stability

PURPOSE

The acromioclavicular ligament complex (ACLC) is the primary stabilizer against horizontal translation with the superior ACLC providing the main contribution. The purpose of this study was to evaluate the specific regional contributions in the superior half of ACLC, where the surgeon can easily access and repair or reconstruct, for posterior translational and rotational stability.

METHODS

The superior half of ACLC was divided into three regions; Region A (0°-60°): an anterior 1/3 region of the superior half of ACLC, Region B (60°-120°): a superior 1/3 region of the superior half of ACLC, and Region C (120°-180°): a posterior 1/3 region of the superior half of ACLC. Fifteen fresh-frozen cadaveric shoulders were used. Biomechanical testing was performed to evaluate the resistance force against passive posterior translation (10 mm) and the resistance torque against passive posterior rotation (20°) during the following the four conditions. (1) Stability was tested on all specimens in their intact condition (n = 15). (2) The ACLC was dissected and stability was tested (n = 15). (3) Specimens were randomly divided into three groups by regions of suturing. Stability was tested after suturing Region A, Region B, or Region C (n = 5 per group). (4) Stability was tested after suturing additional regions: Region A + B (0°-120°), Region B + C (60°-180°), or Region A + C (0°-60°, 120°-180°, n = 5 per group).

RESULTS

The translational force increased after suturing Region A when compared with dissected ACLC (P = 0.025). The force after suturing Region A + B was significantly higher compared to the dissected ACLC (P < 0.001). The rotational torque increased after suturing Region A or Region B compared with dissected ACLC (P = 0.020, P = 0.045, respectively). The torque after suturing the Region A + C was significantly higher compared to the dissected ACLC (P < 0.001).

CONCLUSION

The combined Region A + B contributed more to posterior translational stability than Region B + C or Region A + C. In contrast, combined Region A + C contributed more to posterior rotational stability than Region A + B or Region B + C. Based on these findings, surgical techniques restoring the entire superior ACLC are recommended to address both posterior translational and rotational stability of the AC joint.

Superior clavicle drilling points and fluoroscopic inclination for anatomic coracoclavicular ligament reconstruction: a cadaveric study

PURPOSE

This study aims to investigate the superior clavicle cortex drilling points and fluoroscopic inclination angles for anatomic tunnel drilling in coracoclavicular ligament reconstruction.

METHODS

Twelve cadaveric shoulders with a mean age of 55.9 ± 6.2 years were investigated. Two 2.0 mm Kirschner wires were inserted penetrating the footprint centers of conoid and trapezoid both on the clavicle and coracoid. The location of the Kirschner wires on the superior clavicle cortex was measured. Fluoroscopy was used to obtain three views of shoulder: an anteroposterior, lateral, and cortical ring sign view. Reproducible angles were then recorded.

RESULTS

The Kirschner wire penetrating the conoid was located 40.0 ± 3.9 mm from the distal end and 18.1 ± 3.0 mm from the anterior edge of the clavicle. For the trapezoid, the Kirschner wire was located 19.1 ± 3.6 mm from the distal end and 9.9 ± 3.9 mm from the anterior edge. On the anteroposterior view, the conoid was 11.1° ± 10.1° medially and trapezoid was 26.8° ± 11.8° laterally tilted to the glenohumeral joint line. On the lateral view, the conoid was 42.8° ± 15.1° and trapezoid was 15.5° ± 12.0° superiorly tilted to the scapular spine. On the cortical ring sign view, the conoid was 50.8° ± 12.9° and trapezoid was 14.2 °± 11.0° superiorly tilted to the scapular spine.

CONCLUSIONS

The superior clavicle cortex drilling points and fluoroscopic inclination angles for anatomic tunnel drilling in coracoclavicular ligament reconstruction were demonstrated. Arthroscopy-assisted anatomic coracoclavicular ligament reconstruction has increased in popularity, and these findings may facilitate a more anatomic approach to coracoclavicular ligament reconstruction.