AC Joint Stabilisation Info Evidence Consent

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Pathoanatomy and Mechanism

• Injury to the acromioclavicular joint results in progressive disruption of ligamentous support, beginning with the capsular ligaments and progressing to the coracoclavicular ligaments [6].
• The mechanism of injury is usually direct trauma resulting from a fall on the point of the shoulder [6].
• Indirect injuries to the acromioclavicular joint are rare [6].

Clinical Evaluation

• Higher grade acromioclavicular injuries result in prominence of the distal clavicle [6].
• Localized bruising, swelling, and tenderness are present in acute acromioclavicular injuries [6].
• The sternoclavicular joint should be evaluated for swelling, deformity, and tenderness during physical examination [6].
• Range of motion and rotator cuff strength are typically normal in chronic injuries but may be limited in acute injuries secondary to pain [6].
• The ability to reduce the deformity with manual pressure can help differentiate nonsurgical versus surgical treatment for higher grade injuries [6].
• Horizontal plane translation of the distal clavicle should be assessed manually and compared with the opposite shoulder [6].
• A complete neurologic examination of the upper extremity should be performed to rule out brachial plexus injuries [6].
• Scapular motion should be carefully assessed as scapular dyskinesis can be seen with this type of injury [6].

Imaging

• Plain radiographs for acromioclavicular joint evaluation include an AP view of the clavicle, a caudal tilt view, and an axillary view [6].
• The axillary view is needed to rule out posterior translation of the distal clavicle [6].
• In a normal axillary view, the anterior aspect of the clavicle should lie in the same plane as the anterior aspect of the acromion [6].
• Normal coracoclavicular distance between the superior aspect of the coracoid and the inferior clavicle should be between 11 to 13 mm [6].
• Fracture of the base of the coracoid process should be ruled out because it can result in superior displacement of the clavicle with an intact CC distance, creating a functionally equivalent AC joint separation [6].
• A Zanca view, defined as a modified, underpenetrated AP view with a cephalic tilt of 10° to 15°, gives excellent detail of the distal clavicle [6].
• Weighted views include bilateral AP views with a weight tied to the wrists in relaxed standing [6].
• Weighted views help distinguish between type II and type III separations but are rarely indicated and often are not clinically helpful [6].

Classification

• Rockwood Type I injury is characterized by AC ligament sprain, intact CC ligaments, and a normal CC distance on radiographs [6].
• Rockwood Type II injury is characterized by AC ligament rupture, sprained but intact CC ligaments, and a normal CC distance on radiographs [6].
• Rockwood Type III injury is characterized by disruption of the AC and CC ligaments, increased CC distance, superior displacement of the clavicle of up to 100% of the clavicle width, and a reducible deformity [6].
• A modification of type III injuries has been proposed consisting of type IIIA (horizontally stable) and type IIIB (horizontally unstable) [6].
• Rockwood Type IV injury is characterized by disruption of the AC and CC ligaments with posterior displacement of the clavicle, increased CC distance, distal clavicle herniation into or through the deltotrapezial fascia, and a non-reducible deformity [6].
• Rockwood Type V injury is characterized by disruption of the AC and CC ligaments with greater than 100% displacement of the clavicle superiorly, markedly increased CC distance, and a deformity usually not reducible because of herniation through the deltotrapezial fascia [6].
• Rockwood Type VI injury is characterized by disruption of the AC and CC ligaments with inferior clavicle displacement, resulting in the distal clavicle lying under the acromion or coracoid process [6].

Treatment Indications

• Nonsurgical treatment is recommended for type I and II acromioclavicular injuries [6].
• The recommended treatment for type III injuries is controversial and depends on patient age and activity level [6].
• Surgery is indicated for most acute type IV, V, and VI separations [6].
• Surgery can be performed acutely in selected type III separations in younger, physically active patients, manual laborers, patients with cosmetic concerns, or those with chronic injuries who have persistent symptoms [6].
• Surgery is often recommended for patients with type IIIB (horizontally unstable) separations [6].

Operative Techniques

• The triple anatomical technique is a safe, reproducible, and effective method for restoring acromioclavicular joint stability [1].
• The “suture staple” augmentation for AC/CC reconstruction is a safe, reproducible, and quickly accomplished technique aimed to decrease loss of fixation and failure in higher-risk patients [2].
• Clinical studies are needed to show whether additive ACJ fixation in addition to the all-endoscopic double cerclage EndoButton CC stabilization technique is beneficial [3].
• Reconstruction with iliac crest autograft of the distal clavicle and acromioclavicular-coracoclavicular reconstruction offers a reliable source of bone autograft in the setting of chronic AC joint injuries, posterior displacement of the distal clavicle, and about 20 mm of distal clavicle bone deficiency [4].
• In acute high-grade ACD with a Bigliani type II acromion, Standard CHP, 3D-CHP, and SB approaches produced broadly comparable 24-month functional outcomes and radiographic maintenance [5].

Anatomy & Pathophysiology

Ligamentous Anatomy and Stability

• The horizontal plane stability of the clavicle is provided by the AC ligaments, specifically the posterior and superior portions [12].
• Injury to the AC joint results in progressive disruption of the ligamentous support, beginning with the capsular ligaments and progressing to the CC ligaments [6].
• The extent of injury to the AC and coracoclavicular (CC) ligaments, as well as the amount and direction of clavicle displacement, often determines the severity of AC joint separation [15].

Pathomechanics and Classification

• Type I AC joint injuries involve AC ligament sprain without injury to the CC ligaments, with no AC joint widening or clavicular displacement [11].
• Type II AC joint injuries consist of complete rupture of the AC ligament, CC ligament sprain, widening of the AC joint, and an increase in the CC distance by less than 25% compared with the contralateral shoulder [11].
• Type III AC joint injuries involve disruption of the AC and CC ligaments, widening of the AC joint, and an increase in the CC distance by 25% to 100% compared with the contralateral shoulder [11].
• Type IV AC joint separation is diagnosed when the distal clavicle is displaced posteriorly into the trapezius muscle [11].
• Type V AC joint injury involves disruption of the AC and CC ligaments with a CC distance increased by more than 100% compared with the contralateral shoulder due to disruption of the deltotrapezial fascia [11].
• Type VI AC joint injury is rare and involves inferior displacement of the clavicle into the subcoracoid space [11].
• The Rockwood classification was initially classified into types I, II, and III in 1963 and later expanded in 1984 to include types IV, V, and VI [11].

Radiographic Anatomy and Normal Values

• The normal coracoclavicular distance on an AP radiograph should be between 11 to 13 mm [6].
• The normal CC distance on an AP radiograph should be less than 11 to 13 mm [12].
• The axillary view is needed to rule out posterior translation of the distal clavicle, where the anterior aspect of the clavicle should lie in the same plane as the anterior aspect of the acromion [6].
• A Zanca view is a modified, underpenetrated AP view with a cephalic tilt of 10° to 15° that gives excellent detail of the distal clavicle [6].
• Fracture of the base of the coracoid process can result in superior displacement of the clavicle but an intact CC distance, creating a functionally equivalent AC joint separation [6].

Degenerative Pathophysiology

• Osteoarthritis of the AC joint is more common with advanced age following degeneration of the intra-articular disk, with arthritic deterioration starting in early middle age [12].
• Previous low-grade AC joint separations can result in painful arthritis [12].
• Distal clavicle osteolysis involves localized hyperemia of the distal clavicle resulting in inflammation, bone resorption, microfractures, and secondary arthritis of the AC joint [12].
• Bone and joint edema on MRI correlate with AC joint pain [12].

Classification

Historical Development

• AC joint injuries were initially classified into types I, II, and III in 1963 [11].
• The classification was expanded in 1984 to include types IV, V, and VI [11].
• The classification relies on comparative radiographs of the contralateral shoulder to determine each type [11].

Type I

• Type I injury involves AC ligament sprain without injury to the CC ligaments [6, 11].
• Type I injury presents with no AC joint widening or clavicular displacement [11].
• Radiographs for Type I show a normal CC distance [6].
• The deltotrapezial fascia is intact in Type I injuries [11].

Type II

• Type II injury consists of complete rupture of the AC ligament and sprained but intact CC ligaments [6, 11].
• Type II injury presents with widening of the AC joint [11].
• The CC distance is increased by less than 25% compared with the contralateral shoulder in Type II injuries [11].
• Radiographs for Type II show a normal CC distance [6].
• The deltotrapezial fascia is intact in Type II injuries [11].
• The AC joint deformity is reducible in Type II injuries [11].

Type III

• Type III injury involves disruption of both the AC and CC ligaments [6, 11].
• Type III injury presents with widening of the AC joint [11].
• The CC distance is increased 25% to 100% compared with the contralateral shoulder in Type III injuries [11].
• Type III injuries are characterized by superior displacement of the clavicle of up to 100% of the clavicle width [6].
• The deltotrapezial fascia is disrupted in Type III injuries [11].
• The AC joint deformity is reducible in Type III injuries [6, 11].

Type IV

• Type IV injury involves disruption of the AC and CC ligaments with posterior displacement of the clavicle [6, 11].
• In Type IV injuries, the distal clavicle is displaced posteriorly into the trapezius muscle [11].
• The distal clavicle is herniated into or through the deltotrapezial fascia in Type IV injuries [6].
• The deltotrapezial fascia is disrupted in Type IV injuries [11].
• The AC joint deformity is not reducible in Type IV injuries [6, 11].

Type V

• Type V injury involves disruption of the AC and CC ligaments with greater than 100% displacement of the clavicle superiorly [6].
• The CC distance is increased by more than 100% compared with the contralateral shoulder in Type V injuries [11].
• Type V injury is similar to type III, except the CC distance is increased by more than 100% compared with the contralateral shoulder because of disruption of the deltotrapezial fascia [11].
• Tenting of the overlying skin can result in Type V injuries [11].
• The deltotrapezial fascia is disrupted in Type V injuries [11].
• The AC joint deformity is usually not reducible in Type V injuries because of herniation through the deltotrapezial fascia [6].

Type VI

• Type VI injury involves disruption of the AC and CC ligaments with inferior clavicle displacement [6, 11].
• In Type VI injuries, the distal clavicle lies under the acromion or coracoid process [6].
• Type VI injury involves inferior displacement of the clavicle into the subcoracoid space [11].
• The CC ligaments are intact in Type VI injuries [11].
• The deltotrapezial fascia is disrupted in Type VI injuries [11].
• The radiographic CC distance is decreased in Type VI injuries [11].
• The AC joint deformity is not reducible in Type VI injuries [11].

Clinical Presentation

Mechanism and Pathoanatomy

• The mechanism of injury for AC joint separation is usually direct trauma resulting from a fall on the point of the shoulder [6].
• Indirect injuries to the AC joint are rare [6].
• Injury results in progressive disruption of the ligamentous support of the AC joint, beginning with the capsular ligaments and progressing to the CC ligaments [6].

Physical Examination

• Higher grade AC joint injuries result in prominence of the distal clavicle [6].
• Localized bruising, swelling, and tenderness are present in acute AC joint injuries [6].
• The sternoclavicular joint should be evaluated for swelling, deformity, and tenderness [6].
• Range of motion and rotator cuff strength are typically normal in chronic AC joint injuries but may be limited in acute injuries secondary to pain [6].

Imaging

• Plain radiographs for AC joint evaluation include an AP view of the clavicle, a caudal tilt view, and an axillary view [6].
• The anterior aspect of the clavicle should lie in the same plane as the anterior aspect of the acromion [6].
• Fracture of the base of the coracoid process should be ruled out as it can result in superior displacement of the clavicle with an intact CC distance, creating a functionally equivalent AC joint separation [6].
• Weighted views include bilateral AP views with a weight tied to the wrists in relaxed standing and help distinguish between type II and type III separations [6].
• Weighted views are rarely indicated and often are not clinically helpful [6].

Classification

• Type I AC joint injury involves AC ligament sprain with intact CC ligaments and normal radiographic CC distance [6, 11].
• Type II AC joint injury involves AC ligament rupture with sprained but intact CC ligaments and normal radiographic CC distance [6].
• Type II AC joint injury is characterized by an increase in the CC distance by less than 25% compared with the contralateral shoulder [11].
• Type III AC joint injury involves disruption of the AC and CC ligaments with increased CC distance and superior displacement of the clavicle of up to 100% of the clavicle width [6].
• Type III AC joint injury is characterized by an increase in the CC distance by 25% to 100% compared with the contralateral shoulder [11].
• The deformity in Type III AC joint injury is reducible [6, 11].
• A modification of type III injuries has been proposed consisting of type IIIA (horizontally stable) and type IIB (horizontally unstable) [6].
• Type IV AC joint injury involves disruption of the AC and CC ligaments with posterior displacement of the clavicle into or through the deltotrapezial fascia [6].
• The deformity in Type IV AC joint injury is not reducible [6].
• Type V AC joint injury involves disruption of the AC and CC ligaments with greater than 100% displacement of the clavicle superiorly and a markedly increased CC distance [6].
• Type V AC joint injury is characterized by an increase in the CC distance by more than 100% compared with the contralateral shoulder due to disruption of the deltotrapezial fascia [11].
• Tenting of the overlying skin can result in Type V AC joint injury [11].
• The deformity in Type V AC joint injury is usually not reducible because of herniation through the deltotrapezial fascia [6].
• Type VI AC joint injury involves disruption of the AC and CC ligaments with inferior clavicle displacement where the distal clavicle lies under the acromion or coracoid process [6].
• Type VI AC joint injury is rare [6].

Investigations

Physical Examination

• The sternoclavicular joint should be evaluated for swelling, deformity, and tenderness during the physical examination of the AC joint [6].
• The ability to reduce the deformity with manual pressure can help differentiate nonsurgical versus surgical treatment for higher grade AC joint injuries [6].
• Scapular motion should be carefully assessed as scapular dyskinesis can be seen with AC joint injury [6].

Imaging

• On the axillary view, the anterior aspect of the clavicle should lie in the same plane as the anterior aspect of the acromion [6].
• The normal coracoclavicular distance between the superior aspect of the coracoid and the inferior clavicle should be between 11 to 13 mm [6].
• Fracture of the base of the coracoid process should be ruled out on imaging as it can result in superior displacement of the clavicle with an intact CC distance, creating a functionally equivalent AC joint separation [6].

Classification

• Type I AC joint injury involves AC ligament sprain with intact CC ligaments and a normal CC distance on radiographs [6].
• Type II AC joint injury involves AC ligament rupture with sprained but intact CC ligaments and a normal CC distance on radiographs [6].
• Type III AC joint injury involves disruption of the AC and CC ligaments, increased CC distance, superior displacement of the clavicle of up to 100% of the clavicle width, and a reducible deformity [6].
• Type IV AC joint injury involves disruption of the AC and CC ligaments with posterior displacement of the clavicle, increased CC distance, distal clavicle herniation into or through the deltotrapezial fascia, and a non-reducible deformity [6].
• Type V AC joint injury involves disruption of the AC and CC ligaments with greater than 100% displacement of the clavicle superiorly, markedly increased CC distance, and a deformity that is usually not reducible because of herniation through the deltotrapezial fascia [6].
• Type VI AC joint injury involves disruption of the AC and CC ligaments with inferior clavicle displacement, resulting in the distal clavicle lying under the acromion or coracoid process [6].
• Type I injury involves AC ligament sprain without injury to the CC ligaments, no AC joint widening, and no clavicular displacement [11].
• Type II injury consists of complete rupture of the AC ligament, CC ligament sprain, widening of the AC joint, and an increase in the CC distance by less than 25% compared with the contralateral shoulder [11].
• Type III injury involves disruption of the AC and CC ligaments, widening of the AC joint, and an increase in the CC distance by 25% to 100% compared with the contralateral shoulder [11].
• Type IV injury is diagnosed when the distal clavicle is displaced posteriorly into the trapezius muscle [11].
• Type V injury involves disruption of the deltotrapezial fascia, an increase in the CC distance by more than 100% compared with the contralateral shoulder, and potential tenting of the overlying skin [11].

Treatment

Non-Operative Management

• Nonsurgical treatment is recommended for type I and II acromioclavicular joint injuries [6].
• Nonsurgical management of type I and II injuries involves sling immobilization followed by gradual active range of motion exercises, stretching, and strengthening as tolerated [6].
• Most patients with type I or II injuries regain full shoulder function within 4 to 6 weeks [6].
• Patients with type I or II injuries are at increased risk for painful acromioclavicular joint arthritis [6].
• Between 30% and 50% of young, very active patients with type I or II injuries will have mild to moderate residual pain at the acromioclavicular joint [6].
• The arm sling is usually used for approximately 1 week in type I injuries and for 2 to 3 weeks in type II acromioclavicular joint separations [13].
• Strengthening exercises are started after full range of motion is obtained in the nonsurgical management of type I and II injuries [13].
• Patients should refrain from returning to contact sports or heavy lifting for approximately 2 to 3 months until restoration of full, painless shoulder range of motion [13].
• No evidence supports early surgical management for type I or type II acromioclavicular joint separations [13].
• Retrospective studies have reported persistent symptoms in up to 40% to 50% of patients at 1, 6, and 10 years after type I or II injury [13].
• In one study, 27% of patients with type I or II injuries underwent surgical intervention at a mean of 26 months after injury [13].
• The initial management of type III acromioclavicular joint separations is controversial in the literature and clinical practice [13].
• A 2007 survey of 664 members and residency directors from the American Orthopaedic Society for Sports Medicine found that 86.3% preferred an initial trial of nonsurgical management of uncomplicated type III acromioclavicular joint injuries [13].
• A 2018 systematic review and meta-analysis of 5 randomized controlled trials and 14 cohort studies involving 954 patients found no difference between surgical and nonsurgical groups in terms of functional outcome scores for type III injuries [13].
• In the 2018 systematic review and meta-analysis, patients in the nonsurgical group had a faster return to work and sports, although with an inferior cosmetic appearance [13].
• A recent prospective randomized clinical trial comparing surgical and nonsurgical management of acute type III and IV acromioclavicular joint separations found no statistical differences in validated outcome scores at 1 year follow-up [13].
• In the recent prospective randomized clinical trial, there were similar rates of return to preinjury sporting activity and faster recovery in the nonsurgical group [13].
• Five patients (16%) in the nonsurgical group of the recent prospective randomized clinical trial required surgery for persistent symptoms at a mean of 8.7 months [13].
• Nonsurgical treatment likely results in substantial residual pain and limited function for type IV, V, and VI injuries, though outcomes studies are limited [6].

Surgical Indications

• Surgical treatment is recommended for most patients with type IV, V, and VI acromioclavicular joint injuries [6].
• Surgical management is usually indicated for type IV and V acromioclavicular joint separations given the high likelihood of persistent shoulder pain, dysfunction, and substantial deformity [13].
• Early surgical repair of type III acromioclavicular joint injuries with or without augmentation seems to result in better patient satisfaction and clinical outcomes compared with delayed reconstruction [13].
• A 2016 systematic review found superior functional outcomes in the early surgical group compared with delayed surgery for complete acromioclavicular joint dislocation involving mostly type III injuries [13].
• Partial dislocations or redislocations were found in 26% of cases in the early treatment group compared with 38.1% of cases in the delayed group in the 2016 systematic review [13].
• The rates of complication were 12.5% in the early surgical group and 17.7% in the delayed surgical group, although the differences did not reach statistical significance [13].

Operative Techniques

• The "suture staple" augmentation for acromioclavicular and coracoclavicular reconstruction is a safe, reproducible, and quickly accomplished technique aimed to decrease loss of fixation and failure in higher-risk patients [2].
• Clinical studies are needed to show whether additive acromioclavicular joint fixation in addition to the all-endoscopic double cerclage EndoButton coracoclavicular stabilization technique is beneficial [3].
• The described technique for distal clavicle insufficiency offers a reliable source of bone autograft in the setting of chronic acromioclavicular joint injuries, posterior displacement of the distal clavicle, and about 20 mm of distal clavicle bone deficiency [4].
• In acute high-grade acromioclavicular dislocation with a Bigliani type II acromion, standard hook plate, 3D-planned pre-bent hook plate, and suture-button approaches produced broadly comparable 24-month functional outcomes and radiographic maintenance [5].
• Acute fixation within 3 to 4 weeks of injury of high-grade acromioclavicular joint separations can be successfully performed with various fixation options and without the use of tendon graft [12].
• Delayed reconstruction of acromioclavicular joint separations requires biologic augmentation, either ligament transfer or tendon grafting, in addition to coracoclavicular stabilization [12].
• Anatomic acromioclavicular joint reconstructions are biomechanically superior to nonanatomic techniques, such as the Weaver-Dunn procedure [12].
• The overall methodological quality of the 50 most cited original studies on acromioclavicular joint reconstruction was moderate, highlighting the need for higher-level evidence [10].

Postoperative Rehabilitation

• Patients undergoing arthroscopically assisted acromioclavicular joint reconstruction are kept in sling immobilization for 6 weeks to limit gravity forces placed on the operative construct [14].
• Hand, wrist, and elbow range of motion exercises, as well as pendulum exercises, are initiated immediately postoperatively after arthroscopically assisted acromioclavicular joint reconstruction [14].
• Physical therapy is begun at 4 weeks with gentle shoulder passive range of motion exercises after arthroscopically assisted acromioclavicular joint reconstruction [14].
• Unrestricted active motion is begun at 6 weeks after arthroscopically assisted acromioclavicular joint reconstruction [14].
• Strengthening exercises are initiated at 10 to 12 weeks after arthroscopically assisted acromioclavicular joint reconstruction [14].
• Acute rehabilitation for distal clavicle excision (zero to 7 days postoperative) includes sling, ice, and pendulum exercises [12].
• Subacute rehabilitation for distal clavicle excision (1 to 6 weeks postoperative) involves gradually increasing shoulder range of motion, gentle passive stretching, and reducing sling use as pain permits [12].
• Heavy lifting or strengthening exercises are avoided during the subacute phase (1 to 6 weeks) of rehabilitation after distal clavicle excision [12].
• Late recovery for distal clavicle excision (more than 6 weeks) includes full shoulder range of motion, stretching, and initiation of rotator cuff, scapular stabilizer, and deltoid strengthening [12].
• Heavy weight lifting and return to full activities are tolerated in the late recovery phase (more than 6 weeks) after distal clavicle excision [12].
• Residual pain or soreness can persist for 3 to 4 months after distal clavicle excision and can be aggravated by heavy lifting [12].

Complications

• Complications associated with nonsurgical management of acromioclavicular joint separations include persistent pain, crepitus, deformity, swelling at the acromioclavicular joint, late arthrosis, and persistent instability [17].
• Osteolysis of the distal clavicle has been reported as a complication of nonsurgical management [17].
• Subacromial erosion can occur with the use of a hook plate [17].
• Implant failure and migration, resulting in vascular or neurologic injuries, have been reported [17].
• Kirschner wires and pins are not advised for acromioclavicular joint fixation [17].
• Aseptic foreign body reaction and erosion of the coracoid or clavicle have been reported with the use of synthetic suture loops [17].
• Intrasubstance failure of synthetic grafts has been reported [17].
• Early or late fractures of the clavicle or coracoid process have been reported, especially with surgical techniques that involve tunnels through the coracoid and/or clavicle [17].
• Painful implants related to the hook plate or coracoclavicular screw usually require a second procedure for implant removal [17].
• Ossification of the coracoclavicular space has been reported as a complication following surgery [17].
• Loss of acromioclavicular joint reduction, persistent pain, and instability can potentially complicate surgical outcomes [17].
• Neurologic injuries are rare but can involve nerve root injuries secondary to traction during surgery, direct injury to the suprascapular nerve resulting from aggressive dissection during reconstruction, or injury to the brachial plexus with techniques that pass grafts or suture loops under the coracoid process [17].
• Adhesive capsulitis, osteomyelitis of the acromioclavicular joint, and upper extremity deep vein thrombosis have been reported as complications [17].

Complications

• Surgical treatment of type III acromioclavicular joint separations resulted in an increase in complications compared to nonsurgical treatment [6].
• In a systematic review comparing early and delayed surgical intervention for complete AC joint dislocation, the rate of complications was 12.5% in the early surgical group [13].
• In a systematic review comparing early and delayed surgical intervention for complete AC joint dislocation, the rate of complications was 17.7% in the delayed surgical group [13].
• The difference in complication rates between early and delayed surgical groups for complete AC joint dislocation did not reach statistical significance [13].
• Patients treated nonsurgically for type I and II AC joint injuries are at increased risk for painful AC joint arthritis [6].
• Between 30% and 50% of young, very active patients with type I or II AC joint injuries will have mild to moderate residual pain at the AC joint [6].
• Retrospective studies have reported persistent symptoms in up to 40% to 50% of patients at 1, 6, and 10 years after type I or II AC joint injury [13].
• In a prospective randomized clinical trial of acute type III and IV AC joint separations, five patients (16%) in the nonsurgical group required surgery for persistent symptoms at a mean of 8.7 months [13].
• Partial dislocations or redislocations were found in 26% of cases in the early surgical treatment group for complete AC joint dislocation [13].
• Partial dislocations or redislocations were found in 38.1% of cases in the delayed surgical treatment group for complete AC joint dislocation [13].
• The "suture staple" augmentation technique for AC/CC reconstruction is aimed to decrease loss of fixation and failure in higher-risk patients [2].

Recovery

• The triple anatomical technique for acromioclavicular joint reconstruction is a safe, reproducible, and effective method for restoring acromioclavicular joint stability [1].
• The described technique for distal clavicle insufficiency offers a reliable source of bone autograft in the setting of chronic AC joint injuries, posterior displacement of the distal clavicle, and about 20 mm of distal clavicle bone deficiency [4].
• The investigation established the methodological feasibility of using DSX combined with patient-specific CT models to quantify in vivo ligament behavior during functional shoulder motion [8].

Key Evidence

• [L5] The triple anatomical technique is a safe, reproducible, and effective method for restoring acromioclavicular joint stability. [1] (10.1016/j.eats.2025.103595)
• [L5] Overall, the “suture staple” augmentation for AC/CC reconstruction is a safe, reproducible, and quickly accomplished technique aimed to decrease loss of fixation and failure in higher-risk patients. [2] (10.1016/j.eats.2024.103226)
• [Paper] Clinical studies need to show whether additive ACJ fixation in addition to the all-endoscopic double cerclage EndoButton CC stabilization technique is in fact beneficial. [3] (10.1016/j.eats.2024.103038)
• [L4] The described technique offers a reliable source of bone autograft in the setting of chronic AC joint injuries, posterior displacement of the distal clavicle, and about 20 mm of distal clavicle bone deficiency. [4] (10.1016/j.eats.2025.103496)
• [L3] In acute high-grade ACD with a Bigliani type II acromion, Standard CHP, 3D-CHP, and SB approaches produced broadly comparable 24-month functional outcomes and radiographic maintenance. [5] (10.1186/s12891-026-09778-x)
• [L3] This investigation established the methodological feasibility of using DSX combined with patient-specific CT models to quantify in vivo ligament behavior during functional shoulder motion. [8] (10.1177/23259671251408739)
• [Paper] The overall methodological quality was moderate, highlighting the need for higher-level evidence. [10] (10.1177/23259671251408764)

References

[1] The Triple Anatomical Technique for Acromioclavicular Joint Reconstruction: A True Anatomical Reconstruction Technique Using Synthetic Ligaments With Acromioclavicular Ligament Reconstruction. Arthroscopy Techniques. 2025. DOI: 10.1016/j.eats.2025.103595

[2] Acromioclavicular Joint Reconstruction With Acromioclavicular Ligament Augmentation Using a Knotless, All‐Suture Anchor Construct. Arthroscopy Techniques. 2024. DOI: 10.1016/j.eats.2024.103226

[3] All‐Endoscopic Treatment of Acute Acromioclavicular Joint Dislocation: Coracoclavicular Double Cerclage EndoButton Technique and Acromioclavicular Stabilization Using the Coracoacromial Ligament. Arthroscopy Techniques. 2024. DOI: 10.1016/j.eats.2024.103038

[4] Distal Clavicle Insufficiency: Reconstruction With Iliac Crest Autograft of the Distal Clavicle and Acromioclavicular‐Coracoclavicular Reconstruction. Arthroscopy Techniques. 2025. DOI: 10.1016/j.eats.2025.103496

[5] Early clinical outcomes of standard and 3D-planned pre-bent hook plates versus suture-button fixation for acute Rockwood IIIB–V acromioclavicular dislocation with a Bigliani type II acromion: a retrospective cohort study. BMC Musculoskeletal Disorders. 2026. DOI: 10.1186/s12891-026-09778-x

[6] Aaos Comprehensive Orthopaedic Review 3. Disorders of the Acromioclavicular Joint > II. Traumatic Conditions of the AC Joint.

[8] Preliminary In Vivo Evaluation of Coracoclavicular Ligament Mechanics During Shoulder Elevation After Acromioclavicular Joint Reconstruction. Orthopaedic Journal of Sports Medicine. 2026. DOI: 10.1177/23259671251408739

[10] The 50 Most Cited Original Studies on Acromioclavicular Joint Reconstruction: A Bibliometric and Study-Quality Analysis. Orthopaedic Journal of Sports Medicine. 2026. DOI: 10.1177/23259671251408764

[11] Orthopaedic Knowledge Update Sports Medicine 6. Disorders of the Acromioclavicular Joint, Sternoclavicular Joint, and Clavicle > AC Joint Injuries > Classification.

[12] Aaos Comprehensive Orthopaedic Review 3. Disorders of the Acromioclavicular Joint > III. Atraumatic and Degenerative Conditions of the AC Joint.

[13] Orthopaedic Knowledge Update Sports Medicine 6. Disorders of the Acromioclavicular Joint, Sternoclavicular Joint, and Clavicle > AC Joint Injuries > Management.

[14] Campbell S Operative Orthopaedics 4 Volume Set. ARTHROSCOPIC REPAIR OF POSTERIOR HUMERAL AVULSION OF THE GLENOHUMERAL LIGAMENT > ARTHROSCOPICALLY ASSISTED AC JOINT RECONSTRUCTION > TECHNIQUE 52.28.

[15] Orthopaedic Knowledge Update Sports Medicine 6. Disorders of the Acromioclavicular Joint, Sternoclavicular Joint, and Clavicle > AC Joint Injuries.

[17] Orthopaedic Knowledge Update Sports Medicine 6. Disorders of the Acromioclavicular Joint, Sternoclavicular Joint, and Clavicle > AC Joint Injuries > Complications.