காறை எலும்பின் வெளிமுனைக் கரைவு (Distal Clavicle Osteolysis) தகவல் In-depth

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.

Overview

Diagnosis and Differential Diagnosis

• Clinical signs and symptoms for atraumatic distal clavicular osteolysis are not distinguishable from other shoulder pathologies [1].
• Post-traumatic osteolysis of the distal clavicle should be considered if there is persistent pain after a shoulder injury and bony lesions or instabilities have been excluded [3].
• Non-traumatic osteolysis of the acromial end of the clavicle should be considered in cases of shoulder pain in athletes [4].
• Pre-existing distal clavicle stress fracture or osteolysis must be ruled out before performing the arthroscopic Mumford procedure [17].

Etiology and Risk Factors

• Propionibacterium acnes has been identified as a mediator of distal clavicular osteolysis in a reported case [2].
• Subacromial osteolysis can occur following hook plate fixation for acromioclavicular dislocation [9].
• The risk of subacromial osteolysis following hook plate fixation is minimized by removing the implant within 5.5 months and preventing severe osteolysis by removing it no more than 11.9 months after placement [12].
• Maintaining the acromion-hook angle at 10 degrees or less is recommended to minimize the risk of subacromial osteolysis following hook plate fixation [12].

Surgical Management

• Resection of the distal end of the clavicle resulted in relief of symptoms in nineteen patients with osteolysis, with all but five able to continue sports activities and weight-training [7].
• The combination of distal clavicle resection and antibiotics halted osteolysis in a patient with Propionibacterium acnes–mediated distal clavicular osteolysis, who remained symptom-free at 10 months after surgery [2].
• Arthroscopic distal clavicle excision results in statistically and clinically significant improvements in range of motion and patient-reported outcome measures in carefully selected patients with isolated acromioclavicular joint pathology [5].
• Patients undergoing arthroscopic distal clavicle excision through the direct approach can expect a faster return to activities while obtaining similar long-term outcomes compared with the open procedure [6].
• Both the direct superior approach and the indirect subacromial approach to arthroscopic distal clavicle resection result in successful clinical outcomes with clinically insignificant differences at final follow-up [13].
• Arthroscopic and open distal clavicle excisions both provide significant pain reduction at 1 year with no significant difference in outcome measures between groups, except for VAS pain score improvement [14].
• Open and arthroscopic distal clavicle excision are both effective surgeries to treat recalcitrant acromioclavicular joint pain, providing similarly good to excellent results regarding patient satisfaction and shoulder function at intermediate-term follow-up [22].
• Less residual pain was found using the arthroscopic technique compared to the open technique for distal clavicle excision [22].
• Limited distal clavicle excision of patients with acromioclavicular joint osteoarthritis resistant to conservative treatment reduced pain and improved shoulder function at midterm follow-up [10].
• Coracoclavicular ligament reconstruction is an effective surgical approach for decreasing the incidence of subacromial osteolysis following hook plate fixation [9].
• Dewar's procedure and lateral clavicle resection could be a reliable treatment of chronic acromioclavicular joint separation [19].

Surgical Technique and Biomechanics

• Portal placement is paramount in facilitating surgery and avoiding injury to adjacent extra-articular structures regardless of the technique chosen for distal clavicle resection [8].
• A well-performed distal clavicle excision will likely perform better than a poorly performed one, regardless of whether an open or arthroscopic approach is chosen [16].
• Intraoperative use of ultrasound and cannulated dilators allows surgeons to perform distal clavicle excisions in a more efficient, reproducible, and safer manner [23].
• The supraspinatus fossa portal technique provides a technical option for distal clavicle resection when the patient is in the lateral decubitus position, allowing convenient removal of the posterior edge of the distal clavicle to prevent impingement [24].
• A 5 mm resection of the distal clavicle guaranteed no bone-to-bone abutment in a cadaver model [18].

Contraindications and Limitations

• Distal clavicle resection in patients with rotator cuff tears did not result in better clinical outcome scores or shoulder range of motion and was not associated with a lower risk of reoperation [11].
• Routine distal clavicle excision is not absolutely necessary, even in patients with symptomatic acromioclavicular joint osteoarthritis [15].

Anatomy & Pathophysiology

Bony Anatomy

• The clavicle is the only long bone to ossify by intramembranous ossification [35].
• The clavicle serves as the primary stabilizer between the axial skeleton via the sternoclavicular joint and the appendicular skeleton via the acromioclavicular joint [35].
• The clavicle forms a unique S-shaped curve on the axial view [35].
• The distal clavicle is flat in the AP plane [35].
• The primary blood supply to the clavicle is periosteal, with no nutrient blood supply [35].
• The clavicle is subcutaneous, and its muscular envelope includes the platysma, pectoralis major, deltoid, and some of the strap muscles of the neck [35].
• In the transverse plane, the clavicle resembles an italic S [47].
• The greater radius of curvature occurs at the medial curve of the clavicle, which is anteriorly convex [47].
• The smaller lateral curve of the clavicle is posteriorly convex [47].
• The bone is somewhat rounded in its midsection and medially and relatively flat laterally [47].
• The medial end of the clavicle has a 30% incidence of a rhomboid fossa on its inferior surface where the costoclavicular ligaments insert [47].
• The medial end of the clavicle has a 2.5% incidence of an actual articular surface facing inferiorly toward the first rib [47].
• The middle portion of the clavicle contains the subclavian groove where the subclavius muscle has a fleshy insertion [47].
• The lateral portion of the clavicle has the coracoclavicular process when present [47].
• The conoid ligament attaches to the clavicle at the conoid tubercle [47].
• The trapezoid ligament attaches at the trapezoid line, which lies in an anteroposterior direction just lateral to the conoid tubercle [47].
• The distance from the lateral edge of the clavicle to the medial edge of the conoid tubercle is approximately 45 mm in male and female specimens [47].
• The distance from the lateral edge of the clavicle to the center of the trapezoid tuberosity is approximately 25 mm in male and female specimens [47].
• The trapezius inserts on the posterosuperior surface of the distal end of the clavicle [47].
• The subclavius muscle has a fleshy insertion on the inferior surface of the middle third of the clavicle [47].
• The deltoid originates on the anterior portion of the inner surface of the lateral curve of the clavicle [47].
• The pectoralis major originates from the anterior portion of the medial two-thirds of the clavicle [47].
• The sternocleidomastoid largely originates on the posterior portion of the middle third of the clavicle [47].
• The sternohyoid originates on the clavicle just medial to the origin of the sternocleidomastoid [47].
• The medial anterior curve of the clavicle is an accommodation for the subclavian vein and artery and brachial plexus [47].
• The clavicle is one of the first bones to ossify, beginning from two primary ossification centers (medial and lateral) by 5 to 6 weeks of gestation [46].
• By 7 to 8 weeks of gestation, the clavicle has already assumed its overall contour and “S” shape [46].
• Most growth of the clavicle (80%) occurs from the medial physis [46].
• The lateral epiphysis of the clavicle forms and fuses at around 18 to 19 years of age [46].
• The medial epiphysis of the clavicle is the last in the body to ossify, at the age of 18 to 20 years [46].
• The medial epiphysis of the clavicle is the last to complete ossification, at the age of 23 to 25 years [46].

Ligaments and Soft Tissue

• The coracoclavicular ligaments consist of the conoid (medial) and trapezoid (lateral) components [35].
• The coracoclavicular ligaments are the primary stabilizers to superior (vertical) translation of the distal clavicle [35].
• The superior shoulder suspensory complex is a bone–soft-tissue ring that provides a stable connection of the glenoid and scapula to the clavicle [35].
• The superior shoulder suspensory complex is composed of four bony landmarks: distal clavicle, acromion, coracoid process, and glenoid neck [35].
• The superior shoulder suspensory complex includes the supporting ligamentous complexes of the acromioclavicular joint and the coracoclavicular ligaments [35].
• The supraclavicular nerves originate from cervical roots C3 and C4 and exit from a common trunk behind the posterior border of the sternocleidomastoid muscle [53].
• There are typically three major branches of the supraclavicular nerves (anterior, middle, and posterior) that cross the clavicle superficially from medial to lateral [53].
• The subclavian vein runs directly below the subclavius muscle and above the first rib [53].
• The subclavian artery and brachial plexus lie more posteriorly than the subclavian vein, separated from the vein and clavicle by the scalenus anterior muscle medially [53].
• The brachial plexus is closest to the clavicle in its midportion [53].
• The subclavian vessels are closest to the clavicle at the medial end, with the vein directly apposed to the posterior cortex of the medial clavicle in some cases [53].
• In the middle third of the clavicle, the subclavian artery and vein are a mean of 17 mm and 13 mm from the clavicle, respectively [53].
• In the middle third of the clavicle, the subclavian artery and vein are located at an approximate angle of 60 degrees to the horizontal [53].
• Laterally, the subclavian artery and vein are a mean of 63 mm and 76 mm from the clavicle, respectively [53].
• The pectoralis major muscle originates from the clavicular shaft anteroinferiorly [51].
• The sternocleidomastoid originates superiorly on the medial clavicle [51].
• The pectoralis origin merges with the origin of the anterior deltoid laterally [51].
• The trapezius insertion blends superiorly with the deltoid origin at the lateral margin of the clavicle [51].
• The subclavius muscle inserts on the undersurface of the clavicle and serves as a soft tissue buffer in the subclavicular space superior to the brachial plexus and subclavian vessels [51].
• The platysma usually envelopes the anterior and superior aspects of the clavicle and runs in the subcutaneous tissues [51].
• Anterosuperiorly, the pectoralis major muscle and fascia envelope the medial 60% of the clavicle [51].
• Anterosuperiorly, the lateral 40% of the clavicle is covered by the deltoid muscle and its fascia [51].
• Posterosuperiorly, the trapezius muscle attaches to the clavicle [51].

Pathophysiology

• Distal clavicular osteolysis is a well-known cause of shoulder pain in adults [25].
• Patients with distal clavicular osteolysis present with isolated pain at the distal clavicle and acromioclavicular joint that tends to worsen with activity [25].
• There are two forms of distal clavicular osteolysis: posttraumatic and atraumatic [25].
• Posttraumatic distal clavicular osteolysis is caused by a direct traumatic injury [25].
• Atraumatic distal clavicular osteolysis is attributable to repetitive stress [25].
• In adults, the most common risk factor for stress-induced distal clavicular osteolysis is weightlifting [25].
• Clinical signs and symptoms for atraumatic distal clavicular osteolysis were not distinguishable from other shoulder pathologies [1].
• It is important to consider the possibility of post-traumatic osteolysis of the distal clavicle if there is persistent pain after a shoulder injury and bony lesions or instabilities have been excluded [3].
• Non-traumatic osteolysis of the acromial end of the clavicle should be considered in cases of pain in the shoulder in athletes [4].
• Radiographic findings for distal clavicular osteolysis may range from mild osteopenia to overt osteolysis [25].
• The bilateral Zanca view is especially helpful for diagnosing distal clavicular osteolysis as it profiles the acromioclavicular joint and allows for comparison with the contralateral side [25].
• MRI characteristics of distal clavicular osteolysis include distal clavicular bone marrow edema that is out of proportion to the edema at the acromion [25].
• MRI characteristics of distal clavicular osteolysis include subchondral cystic change [25].
• In advanced cases of distal clavicular osteolysis, periostitis may be observed at the distal clavicle [25].
• The combination of distal clavicle resection and antibiotics halted osteolysis in a case of Propionibacterium acnes–mediated distal clavicular osteolysis [2].
• The patient in the Propionibacterium acnes–mediated distal clavicular osteolysis case remained symptom free at 10 months after surgery [2].
• Distal clavicle excision is a widely accepted surgical treatment for symptomatic acromioclavicular joint pathology, including osteoarthritis, post-traumatic degeneration, and osteolysis [43].
• Mechanisms of failure following distal clavicle excision include inadequate resection, excessive bone removal resulting in instability, unrecognized concomitant pathology, and iatrogenic disruption of the coracoclavicular ligaments [43].
• The reported incidence of reoperation following distal clavicle excision ranges from 4% to 10% [43].
• A direct blow on the point of the shoulder is the commonest reported mechanism of injury that produces a midshaft fracture of the clavicle [50].
• As the shoulder girdle is subjected to compression force directed from laterally, the main strut maintaining position is the clavicle and its articulations [50].
• Failure of the shoulder girdle under lateral compression can occur at the acromioclavicular articulation, in the clavicle, or at the sternoclavicular joint [50].
• Most (85%) clavicle fractures occur in the midshaft of the bone where the bone is narrowest and enveloping soft tissue structures are most scarce [50].
• The direction of the initial deforming force, and both gravitational and muscular forces on the clavicle result in the typical deformity seen after fracture, with the distal fragment being translated inferiorly, anteriorly, and medially (shortened), and rotated anteriorly [50].
• Simple falls from a standing height are unlikely to produce a displaced fracture in a healthy young person but can result in injury in elderly, osteoporotic individuals [50].
• Fractures resulting from trivial mechanisms in elderly, osteoporotic individuals are typically seen in the distal third of the clavicle [50].
• The most common mechanism of injury in clavicle fractures is a direct blow to the shoulder, whether following a fall or because of direct trauma [56].
• Less commonly, a fall on an outstretched hand can result in a clavicle fracture [56].
• Clavicle fractures are rarely open, despite being caused by high-energy trauma [56].
• Type III lateral third clavicle fractures are intra-articular fractures through the acromioclavicular joint with intact coracoclavicular ligaments [56].
• Type III lateral third clavicle fractures are usually stable but can result in the development of acromioclavicular joint arthritis [56].
• The clavicle is not as important as the scapula in terms of muscle origin but still serves as the attachment site of several large muscles [51].
• Muscle attachment plays a significant role in the deformity which results after fracture, with the medial clavicular fragment elevated by the unopposed pull of the sternocleidomastoid muscle [51].
• The distal clavicular fragment is held inferiorly by the deltoid and medially by the pectoralis major after fracture [51].

Classification

• Distal clavicular osteolysis is classified into two forms: posttraumatic distal clavicular osteolysis caused by direct traumatic injury, and atraumatic distal clavicular osteolysis attributable to repetitive stress [25].
• The bilateral Zanca view is helpful for diagnosing distal clavicular osteolysis as it profiles the acromioclavicular joint and allows for comparison with the contralateral side [25].
• MRI characteristics of distal clavicular osteolysis include distal clavicular bone marrow edema that is out of proportion to the edema at the acromion, as well as subchondral cystic change [25].
• In advanced cases of distal clavicular osteolysis, periostitis may be observed at the distal clavicle on MRI [25].

Clinical Presentation

• There are two forms of distal clavicular osteolysis: posttraumatic distal clavicular osteolysis caused by a direct traumatic injury, and atraumatic distal clavicular osteolysis attributable to repetitive stress [25, 59].

Investigations

• A high index of suspicion is needed to diagnose bone osteolysis following acromioclavicular joint reconstruction using synthetic ligament early before irretrievable bone loss occurs [21].
• Special care must be taken to properly identify the acromioclavicular joint and rule out pre-existing distal clavicle stress fracture or osteolysis before performing the arthroscopic Mumford procedure [17].
• The cross-sectional A-frame morphology of the superior cortex of the distal clavicle provides a reproducible landmark that is eliminated approximately 1.0 cm medial to the distal, lateral end of the clavicle, which can be used intraoperatively to determine when adequate resection has been completed [31].
• Inaccurate resection from lack of depth perception and inadequate visualization has been reported in distal clavicle excision [20].
• The use of a fluoroscopic Kirschner wire guide for distal clavicle excision allows for increased confidence and accuracy of complete distal clavicle excision [20].
• The use of a fluoroscopic Kirschner wire guide for distal clavicle excision reduces the likelihood of over-resection injury due to a visual and mechanical reference point [20].
• The use of a fluoroscopic Kirschner wire guide for distal clavicle excision improves visualization and depth perception of the resection [20].
• Subacromial decompression is necessary with the indirect approach when using a fluoroscopic Kirschner wire guide for distal clavicle excision [20].
• K-wire placement into the clavicle can be dangerous if the surgeon is inexperienced with the technique [20].
• Additional radiation burden is necessary for accurate and safe K-wire placement during distal clavicle excision [20].

Treatment

Non-Operative

• Activity modification, NSAIDs, and physical therapy are first-line treatments for distal clavicular osteolysis [25].
• Intra-articular injection of lidocaine and corticosteroids into the acromioclavicular joint is both diagnostic and therapeutic for distal clavicular osteolysis [25].
• Nonoperative treatment with injections, medication, and physical therapy is a good option for in-season athletes with distal clavicular osteolysis [25].

Operative

• Distal clavicle resection is the definitive operative treatment for distal clavicular osteolysis that fails nonoperative management [25].
• Resection of the distal end of the clavicle resulted in relief of symptoms in 19 patients with osteolysis in male athletes [7].
• Following distal clavicle resection for osteolysis in male athletes, all but five of 19 patients were able to continue sports activities and weight-training [7].
• In carefully selected patients with isolated acromioclavicular joint pathology, arthroscopic distal clavicle excision results in statistically and clinically significant improvements in range of motion and patient-reported outcome measures [5].
• Arthroscopic distal clavicle excision provides a faster return to activities compared with open procedure while obtaining similar long-term outcomes for acromioclavicular joint pathology [6].
• Open and arthroscopic distal clavicle excision provide similarly good to excellent results regarding patient satisfaction and shoulder function at intermediate-term follow-up for recalcitrant acromioclavicular joint pain [22].
• Less residual pain was found using the arthroscopic technique compared to open distal clavicle excision [22].
• Both the direct superior approach and the indirect subacromial approach to arthroscopic distal clavicle resection result in successful clinical outcome with clinically insignificant difference at final follow-up [13].
• Limited distal clavicle excision for acromioclavicular joint osteoarthritis resistant to conservative treatment reduced pain and improved shoulder function at midterm follow-up [10].
• The combination of distal clavicle resection and antibiotics halted osteolysis in a patient with Propionibacterium acnes–mediated distal clavicular osteolysis, with the patient remaining symptom-free at 10 months after surgery [2].
• Removing the implant within 5.5 months minimizes osteolysis risk and no more than 11.9 months prevents severe osteolysis following hook plate fixation for acromioclavicular dislocation [12].
• Maintaining the acromion-hook angle at 10 degrees or less is recommended to prevent severe osteolysis following hook plate fixation [12].

Surgical Technique and Considerations

• Resection should be limited to the distal clavicle because there is typically minimal arthrosis on the acromial cartilage surface in younger patients with distal clavicular osteolysis [25].
• A 5 mm resection guaranteed no bone-to-bone abutment in a cadaver model of distal clavicle excision [18].
• A 5-mm distal clavicle resection guaranteed no abutment but decreased joint stiffness in a cadaveric model [27].
• Portal placement remains paramount in facilitating surgery and avoiding injury to adjacent extra-articular structures regardless of the technique chosen for distal clavicle resection [8].
• A fluoroscopic Kirschner wire guide allows for increased confidence and accuracy of complete distal clavicle excision [20].
• A fluoroscopic Kirschner wire guide reduces the likelihood of over-resection injury due to a visual and mechanical reference point [20].
• Subacromial decompression is necessary with the indirect approach for arthroscopic distal clavicle excision using a fluoroscopic K-wire guide [20].
• Additional radiation burden is necessary for accurate and safe K-wire placement in arthroscopic distal clavicle excision using a fluoroscopic guide [20].

Complications

Diagnostic and Preoperative Considerations

• Post-traumatic osteolysis of the distal clavicle should be considered if persistent pain remains after a shoulder injury and bony lesions or instabilities have been excluded [3].

Surgical Complications and Technical Risks

• Portal placement is paramount in both facilitating surgery and avoiding injury to adjacent extra-articular structures during distal clavicle resection [8].
• Distal clavicle fracture is a reported complication of arthroscopic distal clavicle resection [17].
• Acromioclavicular dislocation is a reported complication following arthroscopic distal clavicle resection [8].
• Inaccurate resection due to lack of depth perception and inadequate visualization has been reported as a complication of distal clavicle excision [20].
• Subacromial decompression is necessary with the indirect approach to arthroscopic distal clavicle excision [20].
• Potential complications related to the graft remain to be addressed in coracoid process transfer and distal clavicle resection for chronic acromioclavicular separation [19].

Iatrogenic Osteolysis from Hardware

• Hook plate fixation for acromioclavicular joint separations presents with a high rate of acromial osteolysis [29].
• Prolonged implant retention and higher-grade fracture types significantly increase the risk of subacromial osteolysis following hook plate fixation [33].
• Removing the implant within 5.5 months minimizes osteolysis risk and no more than 11.9 months prevents severe osteolysis following hook plate fixation [12].

Failure Modes and Revision Surgery

• Inadequate resection is a described mechanism of failure leading to persistent symptoms after distal clavicle excision [43].
• Excessive bone removal resulting in instability is a described mechanism of failure leading to persistent symptoms after distal clavicle excision [43].
• Unrecognized concomitant pathology is a described mechanism of failure leading to persistent symptoms after distal clavicle excision [43].
• Iatrogenic disruption of the coracoclavicular ligaments is a described mechanism of failure leading to persistent symptoms after distal clavicle excision [43].
• A subset of patients experience persistent pain, residual instability, or functional limitation following primary distal clavicle excision that requires additional surgical intervention [43].

Recovery

• Patients undergoing arthroscopic distal clavicle excision via the direct approach can expect a faster return to activities compared with the open procedure while obtaining similar long-term outcomes [6].
• Resection of the distal end of the clavicle resulted in relief of symptoms in nineteen patients, with all but five able to continue sports activities and weight-training [7].
• Open and arthroscopic distal clavicle excision provide similarly good to excellent results regarding patient satisfaction and shoulder function at intermediate-term follow-up, though less residual pain was found using the arthroscopic technique [22].
• Both the direct superior approach and the indirect subacromial approach to arthroscopic distal clavicle resection result in successful clinical outcomes with clinically insignificant difference at final follow-up [13].
• A 5-mm distal clavicle resection guaranteed no bone-to-bone abutment in a cadaver model [18].
• The anterior-posterior load to clinical failure of the acromioclavicular joint after 5 mm of resection from the distal clavicle and medial acromion is significantly greater than 1 cm of the resected distal clavicle alone [28].
• Intact acromioclavicular ligaments protect coracoclavicular reconstruction by decreasing the in situ graft force [30].

Key Evidence

• [L4] Clinical signs and symptoms for atraumatic distal clavicular osteolysis (ADCO) were not distinguishable from other shoulder pathologies. [1] (10.1177/17585732261479715)
• [Case_report] The combination of distal clavicle resection and antibiotics halted the osteolysis, and the patient has remained symptom free at 10 months after surgery. [2] (10.1016/j.jse.2015.03.004)
• [L4] It is important to consider the possibility of post-traumatic osteolysis of the distal clavicle if there is persistent pain after a shoulder injury, and bony lesions or instabilities have been excluded. [3] (10.1007/bf00573456)
• [L4] Non-traumatic osteolysis of the acromial end of the clavicle should be borne in mind in cases of pain in the shoulder in athletes. [4] (10.1016/0020-1383(87)90010-6)
• [L4] In carefully selected patients with isolated ACJ pathology, arthroscopic distal clavicle excision results in statistically and clinically significant improvements in range of motion and patient-reported outcome measures. [5] (10.1016/j.jseint.2023.07.014)
• [L3] Among patients undergoing distal clavicle excision for acromioclavicular joint pathology, those having an arthroscopic procedure, specifically through the direct approach, can expect a faster return to activities while obtaining similar long-term outcomes compared with the open procedure. [6] (10.1016/j.arthro.2009.12.007)
• [L4] Resection of the distal end of the clavicle resulted in relief of symptoms in the nineteen patients who were followed, with all but five able to continue sports activities and weight-training. [7] (10.2106/00004623-198365030-00028)
• [Case_report] Regardless of the technique chosen for distal clavicle resection, portal placement remains paramount in both facilitating surgery and avoiding injury to adjacent extra-articular structures. [8] (10.1016/j.jse.2010.08.032)
• [L1] The current analysis suggests coracoclavicular ligament reconstruction as an effective surgical approach for decreasing the incidence of subacromial osteolysis. [9] (10.1016/j.jse.2024.03.018)
• [L4] Limited distal clavicle excision of patients with AC joint osteoarthritis resistant to conservative treatment reduced pain and improved shoulder function at midterm follow-up. [10] (10.1016/j.otsr.2016.01.008)
• [L1] Distal clavicle resection in patients with rotator cuff tears did not result in better clinical outcome scores or shoulder ROM and was not associated with a lower risk of reoperation. [11] (10.1097/corr.0000000000000424)
• [L3] The authors recommend removing the implant within 5.5 months to minimize osteolysis risk and no more than 11.9 months to prevent severe osteolysis, while maintaining the acromion-hook angle at 10 degrees or less. [12] (10.1016/j.jse.2024.09.027)
• [L2] Both the direct superior approach and the indirect subacromial approach to the arthroscopic distal clavicle resection result in successful clinical outcome with clinically insignificant difference at final follow-up. [13] (10.1177/0363546506294855)
• [L1] Arthroscopic and open distal clavicle excisions both provide significant pain reduction at 1 year with no significant difference in outcome measures between groups, except for VAS pain score improvement. [14] (10.1016/j.jse.2006.10.006)
• [L2] Routine distal clavicle excision is not absolutely necessary, even in patients with symptomatic ACJ osteoarthritis. [15] (10.1007/s00167-020-06098-y)
• [L5] A well-performed distal clavicle excision will likely perform better than a poorly performed one, regardless of whether an open or arthroscopic approach is chosen. [16] (10.1016/j.arthro.2018.03.004)
• [L4] Special care must be taken to properly identify the AC joint and rule out pre-existing distal clavicle stress fracture or osteolysis before performing the arthroscopic Mumford procedure. [17] (10.1016/j.arthro.2009.02.008)
• [Abstract] Although distal clavicle excision with 2.5 mm of bone was successful in many specimens, a 5 mm resection guaranteed no bone-to-bone abutment. [18] (10.1016/j.jse.2007.02.105)
• [L4] Although potential complications related to the graft still need to be addressed, Dewar's procedure and lateral clavicle resection could be a reliable treatment of chronic AC joint separation. [19] (10.1016/j.jseint.2022.09.012)
• [Paper] [20] (10.1016/j.eats.2020.10.010)
• [L4] A high index of suspicion is needed to diagnose such complications early before irretrievable bone loss to osteolysis. [21] (10.1111/sae.12035)
• [L3] Open and arthroscopic distal clavicle excision are both effective surgeries to treat recalcitrant acromioclavicular joint pain, providing similarly good to excellent results regarding patient satisfaction and shoulder function at intermediate-term follow-up, though less residual pain was found using the arthroscopic technique. [22] (10.1177/0363546511419633)
• [L5] The technique will allow surgeons to perform distal clavicle excisions in a more efficient, reproducible and safer manner. [23] (10.1016/j.eats.2024.103331)
• [Paper] The introduction of this technique provides a special technical option for distal clavicle resection when the patient is in the lateral decubitus position, allowing convenient removal of the posterior edge of the distal clavicle to prevent impingement. [24] (10.1016/j.eats.2020.08.040)
• [L5] A 5-mm distal clavicle resection guaranteed no abutment but decreased joint stiffness. [27] (10.1016/j.arthro.2007.07.004)
• [L5] This cadaveric study demonstrates that the anterior-posterior load to clinical failure of the AC joint after 5 mm of resection from the distal clavicle and medial acromion is significantly greater than 1 cm of the resected distal clavicle alone. [28] (10.1177/0363546512469873)
• [L3] Although in HP group no implant failure occurred, major disadvantages are initial overcorrection and acromial osteolysis, both of which have no influence on final functional results. [29] (10.1007/s00402-011-1399-x)
• [L5] Intact acromioclavicular ligaments protect the coracoclavicular reconstruction by decreasing the in situ graft force. [30] (10.1177/0363546510374447)
• [L5] The cross-sectional A-frame morphology of the superior cortex of the distal clavicle provides a reproducible landmark that is eliminated approximately 1.0 cm medial to the distal, lateral end of the clavicle, which can be used intraoperatively to determine when adequate resection has been completed. [31] (10.1016/j.jse.2021.10.013)
• [L3] Prolonged implant retention and higher-grade fracture types significantly increase the risk of subacromial osteolysis (SAO). [33] (10.1186/s12891-026-09516-3)
• [L4] [43] (10.1016/j.jse.2026.08.016)

References

[1] Risk factors and management of atraumatic distal clavicular osteolysis: A scoping review. Shoulder & Elbow. 2026. DOI: 10.1177/17585732261479715

[2] Propionibacterium acnes–mediated distal clavicular osteolysis: a case report. Journal of Shoulder and Elbow Surgery. 2015. DOI: 10.1016/j.jse.2015.03.004

[3] Post-traumatic osteolysis of the distal clavicle. Archives of Orthopaedic and Trauma Surgery. 1996. DOI: 10.1007/bf00573456

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