Risk of fracture of the acromion depends on size and orientation of acromial bone tunnels when performing acromioclavicular reconstruction

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.

Risk for Fracture with Acromioclavicular Joint Reconstruction and Strategies for Mitigation

Acromioclavicular (AC) joint injuries are a common cause of shoulder pain, especially among athletes. Surgical reconstruction of the AC joint can lead to complications such as fracture of the coracoid process, clavicle or acromion, which can negatively affect the patient's outcome. The purpose of this review is to discuss the risk factors for fractures associated with AC joint reconstruction, as well as the strategies that can be used to mitigate this risk. Risk factors for fractures include low mineral density, coracoid/clavicle drilling, larger holes in the coracoid, and the number of tunnels used for reconstruction.

Iatrogenic instability of the acromioclavicular joint leads to ongoing impairment of shoulder function even following secondary surgical stabilization

PURPOSE

Iatrogenic instability of the acromioclavicular joint (ACJ) following distal clavicle excision (DCE) represents an infrequent pathology. Revision surgery to restore ACJ stability and alleviate concomitant pain is challenging due to altered anatomic relationships. The purpose of this study was to evaluate the used salvage techniques and postoperative functional and radiological outcomes in retrospectively identify patients with a painful ACJ following DCE. We hypothesized that iatrogenic instability leads to ongoing impairment of shoulder function despite secondary surgical stabilization.

METHODS

9 patients with a painful ACJ after DCE (6 men, 3 women, 43.3 ± 9.4 years) were followed up at a minimum of 36 months after revision surgery. Besides range of motion (ROM), strength and function were evaluated with validated evaluation tools including the Constant score and the DASH score (Disability of the Arm, Shoulder and Hand questionnaire), specific AC Score (SACS), Nottingham Clavicle Score (NCS), Taft score and Acromioclavicular Joint Instability Score (AJI). Additionally, postoperative X-rays were compared to the unaffected side, measuring the coracoclavicular (CC) and acromioclavicular (AC) distance.

RESULTS

At follow-up survey (55.8 ± 18.8 months) all patients but one demonstrated clinical ACJ stability after arthroscopically assisted anatomical ACJ reconstruction with an autologous hamstring graft. Reconstruction techniques were dependent on the direction of instability. The functional results demonstrated moderate shoulder and ACJ scores with a Constant Score of 77.3 ± 15.4, DASH-score of 51.2 ± 23.4, SACS 32.6 ± 23.8, NCS 77.8 ± 14.2, AJI 75 ± 14.7 points and Taft Score 7.6 ± 3.4 points. All patients stated they would undergo the revision surgery again. Mean postoperative CC-distance (8.3 ± 2.8 mm) did not differ significantly from the contralateral side (8.5 ± 1.6 mm) (p > 0,05). However, the mean AC distance was significantly greater with 16.5 ± 5.8 mm compared to the contralateral side (3.5 ± 1.9 mm) (p = 0.012).

CONCLUSION

Symptomatic iatrogenic ACJ instability following DCE is rare. Arthroscopically assisted revision surgery with an autologous hamstring graft improved ACJ stability in eight out of nine cases (88.9%). However, the functional scores showed ongoing impairment of shoulder function and a relatively high overall complication rate (33.3%). Therefore, this study underlines the importance of precise preoperative indication and planning and, especially, the preservation of ACJ stability when performing AC joint resection procedures.

LEVEL OF EVIDENCE

Case series, LEVEL IV.

Current concepts in acromioclavicular joint (AC) instability - a proposed treatment algorithm for acute and chronic AC-joint surgery

BACKGROUND

There exists a vast number of surgical treatment options for acromioclavicular (AC) joint injuries, and the current literature has yet to determine an equivocally superior treatment. AC joint repair has a long history and dates back to the beginning of the twentieth century.

MAIN BODY

Since then, over 150 different techniques have been described, covering open and closed techniques. Low grade injuries such as Type I-II according to the modified Rockwood classification should be treated conservatively, while high-grade injuries (types IV-VI) may be indicated for operative treatment. However, controversy exists if operative treatment is superior to nonoperative treatment, especially in grade III injuries, as functional impairment due to scapular dyskinesia or chronic pain remains concerning following non-operative treatment. Patients with a stable AC joint without overriding of the clavicle and without significant scapular dysfunction (Type IIIA) may benefit from non-interventional approaches, in contrast to patients with overriding of the clavicle and therapy-resistant scapular dysfunction (Type IIIB). If these patients are considered non-responders to a conservative approach, an anatomic AC joint reconstruction using a hybrid technique should be considered. In chronic AC joint injuries, surgery is indicated after failed nonoperative treatment of 3 to 6 months. Anatomic AC joint reconstruction techniques along with biologic augmentation (e.g. Hybrid techniques, suture fixation) should be considered for chronic high-grade instabilities, accounting for the lack of intrinsic healing and scar-forming potential of the ligamentous tissue in the chronic setting. However, complication and clinical failure rates remain high, which may be a result of technical failures or persistent horizontal and rotational instability.

CONCLUSION

Future research should focus on addressing horizontal and rotational instability, to restore native physiological and biomechanical properties of the AC joint.

Acromiohumeral cerclage in reverse total shoulder arthroplasty for recurrent instability

BACKGROUND

Recurrent shoulder instability after reverse total shoulder arthroplasty (rTSA) presents a challenging clinical problem. A handful of cases have been reported describing stability achieved only after revision rTSA with cerclage augmentation. We describe an acromiohumeral cerclage technique, where the humeral component is fixed with a nonabsorbable, high-tensile suture tape looped through transosseous acromial drill tunnels as an augment to salvage shoulder stability.

METHODS

All patients treated with acromiohumeral cerclage in rTSA for instability between November 1, 2015, and February 1, 2020, with minimum 1-year follow-up were included. Demographic information, baseline preoperative and postoperative range of motion at most recent follow-up, American Shoulder and Elbow Surgeons (ASES) shoulder scores, and visual analog scale (VAS) scores were recorded and compared.

RESULTS

Ten patients, 4 female and 6 male, aged 64.3 ± 7.4 years (range, 53-77 years) with the mean postoperative follow-up of 23 months were included; 90% underwent surgery on the dominant side. Patients underwent an average of 2.1 ± 1.9 prior revisions (range, 0-7), over an average of 10.4 months (range, 0-72 months), before revision with suture cerclage augmentation was performed. All patients either had significant past shoulder history at other institutions and/or comorbidities that added significant complexity to their cases, with an average of 0.6 ± 0.9 (range, 0-3) prior other shoulder operations performed before their initial rTSA. The average decrease in VAS score among the 10 patients was 4.3 ± 2.7 (P < .05), ranging from 0 to 8 points. The average increase in ASES score was 51.3 ± 21 (P < .05), ranging from 13.3 to 69.9 points. The average increase in active forward elevation for 8 patients was 79° ± 39° (P = .0008), ranging from 40° to 160°. All patients have remained stable with well-positioned prostheses since their final operations with no recurrent dislocations or acromial complications. Two patients unable to travel for an office visit were contacted via phone and answered questions to obtain postoperative ASES and VAS scores.

CONCLUSION

Acromiohumeral cerclage suture augmentation in revision rTSA may be a useful, simple surgical strategy to employ with other revision and augmentation techniques to treat cases of recurrent, chronic instability, particularly in the setting of multiple revisions.

Evaluation and Management of the Contact Athlete's Shoulder

Shoulder injuries are common in contact athletes and vary in severity because of the required complex interplay of shoulder stability and range of motion for proper function. Pathology varies based on sport but most commonly includes shoulder instability, acromioclavicular injuries, traumatic rotator cuff tears, and brachial plexus injuries. Acute management ranges from reduction of shoulder dislocations to physical examination to determine the severity of injury. Appropriate radiographs should be obtained to evaluate for alignment and fracture, with magnetic resonance imaging commonly being necessary for accurate diagnosis and management. Treatments range from surgical stabilization in shoulder instability to repeat examinations and physical therapy. Return-to-play decision making can be complex with avoidance of reinjury and player safety being of utmost concern. Appropriate evaluation and treatment are vital because repeat injury can lead to long-term effects due to the relatively high effectsometimes seen in contact sports.

Grade III Acromioclavicular Separations Treated With Suspensory Fixation Techniques: A Systematic Review of Level I Through IV Studies

Purpose

To perform a systematic review comparing clinical outcomes, radiographic outcomes, and complication rates after acute (surgery ≤6 weeks from injury) versus chronic (surgery >6 weeks from injury) acromioclavicular joint reconstructions for grade III injuries using modern suspensory fixation techniques.

Methods

We performed a systematic review of the literature examining acute versus chronic surgical treatment of Rockwood grade III acromioclavicular joint separations using the Cochrane registry, MEDLINE database, and Embase database over the past 10 years according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) guidelines. The inclusion criteria included techniques using suspensory fixation, a minimum study size of 3 patients, a minimum follow-up period of 6 months, human studies, and English-language studies. The methodology of each study was evaluated using the Methodological Index for Non-randomized Studies (MINORS) tool for nonrandomized studies and the revised Cochrane risk-of-bias (RoB 2) tool for randomized controlled trials.

Results

The systematic review search yielded 20 studies with a total of 253 patients. There were 2 prospective randomized controlled trials, but most of the included studies were retrospective. On comparison of acute surgery (≤6 weeks) and chronic surgery (>6 weeks), individual studies reported a range of Constant scores of 84.4 to 98.2 and 80.8 to 94.1, respectively. The ranges of radiographic coracoclavicular distances reported at final follow-up also favored acute reconstructions, which showed improved reduction (9.2-15.7 mm and 11.7-18.6 mm, respectively). The reported complication rates ranged from 7% to 67% for acute reconstructions and from 0% to 30% for chronic reconstructions.

Conclusions

The ranges in the Constant score may favor acute reconstructions, but because of the heterogeneity in the surgical techniques in the literature, no definitive recommendations can be made regarding optimal timing.

Level of Evidence

Level IV, systematic review of Level I through IV studies.

Acromioclavicular joint reconstruction implants have differing ability to restore horizontal and vertical plane stability

PURPOSE

Persistent acromioclavicular joint (ACJ) instability following high grade injuries causes significant symptoms. The importance of horizontal plane stability is increasingly recognised. There is little evidence of the ability of current implant methods to restore native ACJ stability in the vertical and horizontal planes. The purpose of this work was to measure the ability of three implant reconstructions to restore native ACJ stability.

METHODS

Three groups of nine fresh-frozen shoulders each were mounted into a robotic testing system. The scapula was stationary and the robot displaced the clavicle to measure native anterior, posterior, superior and inferior (A, P, S, I) stability at 50 N force. The ACJ capsule, conoid and trapezoid ligaments were transected and the ACJ was reconstructed using one of three commercially available systems. Two systems (tape loop + screw and tape loop + button) wrapped a tape around the clavicle and coracoid, the third system (sutures + buttons) passed directly through tunnels in the clavicle and coracoid. The stabilities were remeasured. The data for A, P, S, I stability and ranges of A-P and S-I stability were analyzed by ANOVA and repeated-measures Student t tests with Bonferroni correction, to contrast each reconstruction stability versus the native ACJ data for that set of nine specimens, and examined contrasts among the reconstructions.

RESULTS

All three reconstructions restored the range of A-P stability to that of the native ACJ. However, the coracoid loop devices shifted the clavicle anteriorly. For S-I stability, only the sutures + buttons reconstruction did not differ significantly from native ligament restraint.

CONCLUSIONS

Only the sutures + buttons reconstruction, that passed directly through tunnels in the clavicle and coracoid, restored all stability measures (A, P, S, I) to the native values, while the tape implants wrapped around the bones anteriorised the clavicle. These findings show differing abilities among reconstructions to restore native stability in horizontal and vertical planes. (300 words).

Minimum 10-Year Outcomes After Revision Anatomic Coracoclavicular Ligament Reconstruction for Acromioclavicular Joint Instability

Background:

Revision surgery in cases of previously failed primary acromioclavicular (AC) joint stabilization remains challenging mainly because of anatomic alterations or technical difficulties. However, anatomic coracoclavicular ligament reconstruction (ACCR) has been shown to achieve encouraging biomechanical, clinical, and radiographic short-term to midterm results.

Purpose:

To evaluate the clinical and radiographic long-term outcomes of patients undergoing revision ACCR after failed operative treatment for type III through V AC joint injuries with a minimum 10-year follow-up.

Study Design:

Case series; Level of evidence, 4.

Methods:

A retrospective chart review was performed on prospectively collected data within an institutional shoulder registry. Patients who underwent revision ACCR for type III through V AC joint injuries between January 2003 and December 2009 were analyzed. Clinical outcome measures included the American Shoulder and Elbow Surgeons (ASES) score, Simple Shoulder Test (SST), and Single Assessment Numeric Evaluation (SANE). The coracoclavicular distance (CCD) was measured for radiographic analysis immediately postoperatively and at last postoperative follow-up.

Results:

A total of 8 patients with a mean age at the time of surgery of 44.6 ± 10.6 years and a mean follow-up of 135.0 ± 17.4 months (range, 120-167 months) were eligible for inclusion in the study. The time from initial AC joint stabilization until revision surgery was 10.2 ± 12.4 months (range, 0.5-36 months); 62.5% of the patients had undergone more than 2 previous AC joint surgical procedures. The ASES score improved from 43.9 ± 22.4 preoperatively to 80.6 ± 28.8 postoperatively (P = .012), the SST score improved from 4.4 ± 3.6 preoperatively to 11.0 ± 2.2 postoperatively (P = .017), and the SANE score improved from 31.4 ± 27.3 preoperatively to 86.9 ± 24.1 postoperatively (P = .018) at final follow-up. There was no significant difference in the CCD (P = .08) between the first (7.6 ± 3.0 mm) and final (10.6 ± 2.8 mm) radiographic follow-up (mean, 50.5 ± 32.7 months [range, 18-98 months]).

Conclusion:

Patients undergoing revision ACCR after failed operative treatment for type III through V AC joint injuries maintained significant improvement in clinical outcomes at a minimum 10-year follow-up.

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.

Treatment of acute high-grade acromioclavicular joint dislocation

Acromioclavicular (AC) joint dislocations account for about 9% of shoulder injuries. Among them, acute high-grade injury following high-energy trauma accounts for a large proportion of patients requiring surgical treatment. However, there is no gold standard procedure for operative treatment of acute high-grade AC joint injury, and several different procedures have been used for this purpose in clinical practice. This review article summarizes the most recent and relevant surgical options for acute high-grade AC joint dislocation patients and the outcomes of each treatment type.

Synthetic coracoclavicular ligament vs. coracoclavicular suspensory construct for treatment of acromioclavicular dislocation: a biomechanical study

BACKGROUND

A synthetic ligament (LockDown, Worcestershire, England) has become available to treat complete acromioclavicular dislocation with promising clinical results and potential benefit to avoid postoperative loss of reduction. We investigated the biomechanics of this synthetic ligament in a simulated immediate postoperative rehabilitation setting, hypothesizing that the synthetic ligament would demonstrate less superior coracoclavicular displacement to cyclic loading and higher ultimate load-to-failure values than a coracoclavicular suspensory construct.

METHODS

Seven matched-pair cadaveric shoulders (mean age at time of death, 79 years) were loaded cyclically and to failure. One specimen in each pair was randomly assigned to the synthetic ligament or coracoclavicular suspensory construct. Superiorly directed 70-N cyclic loading for 3000 cycles at 1.0 Hz was applied through the clavicle in a fixed scapula simulating physiologic states during immediate postoperative rehabilitation, followed by a load-to-failure test at 120 mm/min.

RESULTS

After 3000 cycles, the superior displacement of the clavicle in the synthetic ligament (9.2 ± 1.1 mm) was 225% greater than in the coracoclavicular suspensory construct (2.8 ± 0.4 mm, 95% confidence interval [CI] 3.4, 8.3; P < .001). Average stiffness of the synthetic ligament (32.8 N/mm) was 60% lower than that of the coracoclavicular suspensory construct (81.9 N/mm, 95% CI 43.3, 54.9; P < .001). Ultimate load-to-failure of the synthetic ligament was 23% (95% CI 37.9, 301.5; P = .016) lower than the coracoclavicular suspensory construct (580.5 ± 85.1 N and 750.2 ± 135.5 N, respectively).

CONCLUSION

In a simulated immediate postoperative cadaveric model, the synthetic ligament demonstrated poorer biomechanics than the coracoclavicular suspensory construct. These findings suggest that a coracoclavicular suspensory construct may be preferable to a synthetic ligament if early rehabilitation is intended.

The importance of biomechanical properties in revision acromioclavicular joint stabilization: a scoping review

PURPOSE

Treatment of failed primary reconstruction of the unstable acromioclavicular (AC) joint remains challenging for orthopaedic surgeons. When approaching revision cases, the reason for failure has to be precisely identified. The purpose of this manuscript was to perform a critical review of the literature regarding treatment options for failed AC joint stabilization techniques and to provide a treatment algorithm for salvage procedures.

METHODS

A thorough search included electronic databases for articles published up to April 15th, 2019. Inclusion criteria were set as (1) studies that reported on clinical outcomes following surgical or conservative treatment of AC joint dislocation; (2) studies reporting on failure or complications of primary treatment; (3) chronic instabilities caused by delayed or secondary treatment as well as (4) revision and salvage procedures.

RESULTS

The search strategy identified a total of 3269 citations. The final dataset comprised 84 studies published between 1954 and 2019. A total of 5605 patients (9.63% females) were involved with a mean age of 34.5 years. Overall, complication rates varied between 5 and 88.9% in patients with AC joint instability.

CONCLUSION

In the current literature, evidence for treatment of revision AC joint instability is still lacking, however, surgical treatment continues to evolve. The importance of failure analysis and clinically relevant algorithms were highlighted in this review. Adequately restoring native joint biomechanics is needed for ensuring an optimal healing environment that will translate into patient satisfaction and long-term stability.

LEVEL OF EVIDENCE

V.

A Modified Arthroscopic Technique of Gracilis Tendon Graft with Double Fixation System for Treatment of Type V Acromioclavicular Injuries: A Case Report

CASE

A 48-year-old male patient with a type V acromioclavicular injury with a 3-tendon acute cuff tear, anterior glenohumeral dislocation, and an axillary posttraumatic neuropathy is presented. The rotator cuff tear was sutured and an all-arthroscopic-modified coracoclavicular ligaments (CCLs) reconstruction technique was performed with a gracilis tendon graft and a double knotless suture fixation system.

CONCLUSIONS

An arthroscopic approach allows the surgeon to identify and treat associated glenohumeral lesions in type V acromioclavicular dislocations. In addition, the modified CCL reconstruction technique addresses effectively the AC instability.

Arthroscopic Coracoclavicular Fixation Technique Using Multiple All-Suture Anchors

Acromioclavicular (AC) joint dislocation is a common injury, particularly among active young individuals. Numerous surgical procedures for treating acute, high-grade AC joint dislocation have been reported. However, no standard surgical procedure that restores the normal kinematics of the AC joint is available. Among the available coracoclavicular (CC) fixation techniques, cortical button fixation was recently introduced, and it has had successful outcomes. Moreover, it is advantageous because it can be used in arthroscopic procedures. However, because of the limited number of fixation tools, a fundamental problem in terms of horizontal instability and gradual subsidence of cortical buttons has been observed, eventually leading to a threat to vertical stability. Therefore, we developed a unique CC fixation technique with multiple small tunnels using all-suture anchors, which may overcome potential complications caused by cortical buttons that require bone tunnels with relatively large diameters. This arthroscopic CC fixation technique was designed to achieve the ideal horizontal and vertical stability that may restore native AC kinematics.

Arthroscopic Coracoclavicular Fixation Using Multiple Low-Profile Devices in Acute Acromioclavicular Joint Dislocation

PURPOSE

To introduce an arthroscopically assisted coracoclavicular (CC) fixation technique using multiple low-profile devices to evaluate the clinical and radiologic outcomes in patients with acute high-grade acromioclavicular (AC) joint dislocation.

METHODS

Between July 2014 and September 2015, cases of AC joint dislocation that were treated with arthroscopic CC fixation using multiple low-profile devices with a minimum follow-up of 24 months were included. We measured the vertical coracoclavicular distance (CCD) on the anteroposterior view and the horizontal acromioclavicular distance on 3-dimensional computed tomography images to evaluate the changes in radiologic outcomes before and after surgery. We compared final radiologic outcomes between initial AC reduction groups based on hierarchical clustering. Clinical outcomes were evaluated using the Constant-Murley score.

RESULTS

We enrolled 27 patients in total, and the mean follow-up period was 27.2 months. The mean CCD of the injured shoulder was 13.68 ± 3.98 mm preoperatively and decreased to 5.72 ± 1.68 mm immediately postoperatively but increased to 7.32 ± 2.29 mm at last follow-up (P = .07). Horizontal displacement of the distal clavicle was 1.1 ± 1.0 mm immediately postoperatively but decreased to 0.9 ± 0.6 mm at last follow-up (P < .05). In particular, in the 2 groups that were determined using the hierarchical cluster analysis, patients with excellent recovery of the initial CCD (20 patients) showed less of an increase in the CCD at last follow-up than did those in the other group (7 patients) (P < .001). The Constant-Murley score was 93.5 ± 2.7 points on the injured side at last follow-up (P = .074).

CONCLUSIONS

Our CC fixation technique with multiple low-profile devices exhibited satisfactory clinical and radiologic outcomes. In particular, ensuring good initial recovery of the CCD and the precise placement and location of the AC joints was important in maintaining the proper AC position at the final follow-up.

LEVEL OF EVIDENCE

Level IV, case series.

Acromioclavicular joint dislocation: a Dog Bone button fixation alone versus Dog Bone button fixation augmented with acromioclavicular repair-a finite element analysis study

BACKGROUND

Suspension suture button fixation was frequently used to treat acromioclavicular joint (ACJ) dislocation. However, there were many studies reporting about complications and residual horizontal instability after fixation. Our study compared the stability of ACJ after fixation between coracoclavicular (CC) fixation alone and CC fixation combined with ACJ repair by using finite element analysis (FEA).

MATERIALS AND METHODS

A finite element model was created by using CT images from the normal shoulder. The model 1 was CC fixation with suture button alone, and the model 2 was CC fixation with suture button combined with ACJ repair. Three different forces (50, 100, 200 N) applied to the model in three planes; inferior, anterior and posterior direction load to the acromion. The von Mises stress of the implants and deformation at ACJs was recorded.

RESULTS

The ACJ repair in the model 2 could reduce the peak stress on the implant after applying the loading forces to the acromion which the ACJ repair could reduce the peak stress of the FiberWire at suture button about 90% when compared to model 1. And, the ACJ repair could reduce the deformation of the ACJ after applying the loading forces to the acromion in both vertical and horizontal planes.

CONCLUSION

This FEA supports that the high-grade injuries of the ACJ should be treated with CC fixation combined with ACJ repair because this technique provides excellent stability in both vertical and horizontal planes and reduces stress to the suture button.