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远端锁骨切除术（Mumford 手术）

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A Mumford procedure (distal clavicle excision) removes the small worn outer tip of the collarbone to ease shoulder pain at the AC joint. What the keyhole operation involves and what recovery looks like.

Updated Oct 2026
锁骨外侧端与肩胛骨相接处的示意图。
锁骨的外侧端，位于肩锁关节处。 Kieran Hirpara 4.0

本页面由机器翻译，尚未经临床医生审核。英文版本为权威版本。

为何建议进行此手术

Mater Private Hospital Rockhampton 的上肢外科医生 Kieran Hirpara 医生会从适合您病情的最微创方案开始。患者通常由其全科医生（GP）转诊至我们的诊所；如果理疗师建议您就诊，您仍需获得全科医生的转诊才能符合 Medicare 报销资格。我们的评估包括您的病史、体格检查以及必要时的影像学检查，用以弄清是什么引起了您的疼痛。对于这类长期存在的关节磨损，我们通常先尝试非手术治疗，例如调整活动和物理治疗；当这些措施未能带来足够改善时，才会考虑手术。

此手术会从锁骨外侧端切除一小块骨头，位于锁骨与肩部顶端相接的关节处。它适用于疼痛来自该关节磨损，或因反复举重物导致骨质破坏的患者，并且只在维持关节稳定的韧带完好时才进行。切除这一小块骨头后，粗糙的骨面就不再相互摩擦。目标是减轻疼痛，让肩部活动更自如；此手术的微创和开放两种方式在术后1年时都能显著减轻疼痛。

术前

您的外科医生会利用您已经做过的影像检查来规划手术，例如肩部的X光、MRI或超声检查。这些影像能清楚显示关节，并有助于决定需要切除多少骨骼。手术当天，您需要在手术前七小时停止进食和饮水。我们要求七小时而不是六小时，以便在手术室排程进度提前时，可以将您的手术提前。您的外科医生会告诉您哪些常规药物需要停用，哪些需要继续服用。请随身携带一份您服用的所有药物的书面清单。请安排他人在术后开车送您回家。请穿着宽松、舒适且易于穿脱的衣物。如果您有其他健康状况，可能需要进行血液检查或由麻醉师进行评估。

手术当天

您将抵达医院的手术入院单元，在此办理入院手续并进行术前准备。麻醉师将在术前与您会面，并详细说明这两部分麻醉方案。本手术在全身麻醉联合区域神经阻滞下进行。随后，您将被带入手术室进行手术。

您将在复苏区苏醒，护士会在那里监护您，直至麻醉消退。待您情况平稳后，根据手术类型及恢复情况，您将被转入病房或回家。

手术内容

这是一种微创手术。您的外科医生会在肩部周围做几个小切口，包括后侧至少一个，并借助置入关节内的小摄像头进行操作。摄像头会把关节显示在屏幕上，因此无需做大切口来观察关节。

通过这些小切口，您的外科医生会从锁骨外侧端切除约 5 mm 的骨头。这足以让关节处粗糙、磨损的骨面不再相互摩擦。您的外科医生会小心地控制切除的骨量，既足以缓解疼痛，又能保护维持关节稳定的韧带和关节囊。保护这些结构很重要，因为切除过多的骨骼可能使锁骨变得不稳定。

小切口以缝线缝合，并在上面覆盖敷料。这块敷料您需要保留约 10 天。

术后

大多数患者在此手术后需在医院过一晚，但部分患者可能当天即可回家。请安排人在您回家后的最初 24 小时内陪同您。最初一两天您会感到疼痛；我们会给您药物以保持舒适，而且由于神经阻滞，肩部可能会麻木一段时间。神经阻滞后最初 24 小时内出现麻木和无力是预料之中的。如果在神经阻滞消退后（约 24 小时），您的手臂、手或手指仍然没有感觉或无法活动，请致电诊所。您的手臂将佩戴简易吊带以提供舒适感；进行锻炼和清洗时需取下吊带。我们会将敷料保留约 10 天；除非我们告知您，否则请勿在此之前自行拆除。我们会在复诊时为您更换或拆除敷料。

恢复

最初一两天，您的肩部会感到酸痛，并可能有肿胀感。我们给您的止痛药能让您保持舒适，神经阻滞带来的麻木在开始时也有帮助。让手臂有支撑地休息，并轻柔地进行锻炼，通常能缓解不适。大多数人发现，在最初两周左右，酸痛会稳步减轻。

您的手臂会佩戴一个简易吊带以提供舒适感。在进行锻炼和清洗时，您需要取下吊带，物理治疗师会告诉您先从哪些动作开始。这些动作从轻柔开始，随着疼痛减轻逐步加强。一旦您感觉稳当，就可以在家中用手做一些轻松的事情，例如吃饭或写字。请避免提任何重物，也不要忍痛硬撑。

随着活动能力恢复，日常活动会变得更容易。穿衣、举手过头以及向手术侧侧卧睡觉都会逐渐改善。在早期，用额外的枕头垫高上身睡觉可能会更舒适。一旦外科医生允许您驾驶（通常在六周复查时），您就可以重新开车；请参阅上肢手术后驾驶了解更多详情。办公室工作和轻松的日常事务通常在 2 至 6 周内恢复，而体育运动或健身房训练等较重的活动需要更长时间，为 3 至 6 个月。

每个人的愈合速度不同，因此您的时间表可能有所不同。您的外科医生和物理治疗师会在每次复诊时为您提供指导。

可能出现的问题

大多数患者恢复良好，但偶尔也可能出现问题。您的外科医生和医疗团队会密切监测您的状况，以便尽早发现任何问题。

有时术后疼痛会持续存在。这是此手术最常见的问题。如果切除的骨骼略多或略少，或者有一小块骨头重新长出来，就可能出现这种情况。如果您的肩部仍像以前那样酸痛，或者在一段时间的缓解之后疼痛复发，请在下次复诊时提出。有时需要再次手术来解决。

切除过多的骨骼可能导致另一种问题。维持锁骨稳定的韧带和关节囊可能受到干扰，使关节松动或不稳定。您可能会注意到锁骨好像在移位或发出咔哒声，或者在活动手臂时感觉关节不牢靠。如果关节在手术前就已经松动，这种风险会更大。不稳定的关节可能需要再次手术来重建韧带。如果关节感觉松动或以新的方式移动，请在下次复诊时告诉您的外科医生。

其他问题并不常见，但值得了解。这些包括感染、僵硬、骨折、关节自发融合，以及一种称为复杂区域疼痛综合征的持续性疼痛病症。需要留意的感染迹象包括发热、伤口周围发红扩散，或伤口渗出液体或脓液。如果您注意到其中任何一种，请当日致电诊所。尽管服用了止痛药，疼痛仍持续加重，也需要当日致电诊所。微创手术后关节脱位的情况也有报道。如果在撞击或跌倒后，您的肩部突然形状改变、向前下垂，或感觉非常疼痛且不稳定，请立即联系诊所。

本页上的并发症表列出了典型的发生率，如果您想了解具体数据，可以参考该表。

何时联系我们

大多数问题只要您告诉我们，就能被及早发现。如果您出现发热、伤口周围发红扩散，或伤口渗出液体或脓液，请当日致电诊所。如果尽管服用了止痛药，疼痛仍持续加重，也请当日致电诊所。如果您的小腿出现肿胀或疼痛，或出现呼吸急促或胸痛，请前往急诊科。这些可能是血栓的征兆。如果您的手指或手变得苍白、发冷、发白、发青或发黑，也请前往急诊科。如果在神经阻滞消退后（约 24 小时），您的手臂、手或手指仍然没有感觉或无法活动，请致电诊所。如果无法联系到诊所，请前往离您最近的急诊科。

在哪里阅读更多关于该疾病的资料

本页介绍的是手术本身。它所治疗的两种疾病各有自己的页面，分别介绍了证据显示手术在何时有效、何时无效：关节磨损在肩锁关节骨关节炎页面上有介绍，而举重者型（即锁骨末端发生溶解破坏）则在锁骨远端骨溶解页面上有介绍。

Reviewed by Dr Kieran Hirpara · 7 August 2026.

Want the clinical detail? Read the clinician version.

Talk to your treating clinician for advice specific to you.

For an appointment with the CQ Hand + Upper Limb team, ask your GP about a referral or visit www.cqupperlimb.com.

Evidence & references

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

  • Simple excision of the outer end of the clavicle has yielded satisfactory results in patients with complete dislocation and subluxation of the acromioclavicular joint, with no residual upward displacement disturbing the patients [2].
  • Excision of the outer end of the clavicle is preferred for old dislocations, while open reduction and internal fixation are not recommended due to complications and poor functional results [16].
  • Open distal clavicle resection yields good to excellent results in properly selected patients and does not create significant subjective or objective weakness [3].
  • In appropriately selected patients, open or arthroscopic distal clavicle resection is necessary to relieve symptoms of painful conditions of the acromioclavicular joint [7].
  • Arthroscopic distal clavicle resection has provided more 'good or excellent' results than the open procedure, but is comprised of low-level evidence [6].
  • 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 [8].
  • 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 [9].
  • 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 [5].
  • 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 [18].
  • 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 [19].
  • Incomplete excision and regrowth of the distal clavicle are the most common causes of revision [12].
  • Regeneration of the excised portion of clavicle occurs frequently and may produce an unacceptable result, and may be more likely to occur in the younger patient population [13].
  • Horizontal instability of the clavicle is evident with distal clavicle resection of greater than 10 mm [15].
  • 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 [17].
  • Routine distal clavicle resection in the setting of rotator cuff repair does not result in improved outcomes for patients with no difference being observed at 24 months post surgery [11].
  • A records review found that 10 of 894 (1.1%) rotator cuff repairs underwent subsequent distal clavicle resection [40].
  • 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 [1].
  • The use of intraoperative ultrasound and cannulated dilators allows surgeons to perform distal clavicle excisions in a more efficient, reproducible and safer manner [4].
  • A novel anterior portal technique for arthroscopic distal clavicle excision yields a safe corridor for placement of instruments in a reliable manner that does not disrupt the important stabilizers of the glenohumeral or AC joints [20].
  • Clavicular reconstruction may be the treatment of choice in patients with excess resection of the clavicle [14].

Anatomy & Pathophysiology

Bony Anatomy

  • The clavicle is the first bone to ossify, occurring at the fifth week of gestation [59].
  • The clavicle is the only long bone to ossify by intramembranous ossification [59, 65].
  • The medial (sternal) epiphysis of the clavicle is the last ossification center to fuse, occurring at age 20 to 25 years [59].
  • The primary blood supply to the clavicle is periosteal, and no nutrient artery is present [59, 65].
  • The distal clavicle is flat in the anteroposterior plane [65].
  • The scapula has only one true diarthrodial articulation, the acromioclavicular joint [59].
  • The acromion has three ossification centers: the metacromion (base), the mesoacromion (middle), and the preacromion (tip) [59].
  • Failure of fusion of the acromial ossification centers results in os acromiale [59].
  • The coracoid process serves as an attachment site for the coracoacromial ligament, coracoclavicular ligaments, conjoined tendon, and pectoralis minor muscle [70].

Ligaments and Joint Structures

  • The acromioclavicular joint is a small diarthrodial joint with an interposed fibrocartilaginous disk [59].
  • The acromioclavicular joint is a planar diarthroidal joint that couples scapular and sternoclavicular motion [32].
  • A fibrocartilaginous load-bearing disk cushions the high contact stress of the acromioclavicular joint when load is placed across the small articular surface area [32].
  • The superior and posterior acromioclavicular ligaments are the primary stabilizers to anterior and posterior (horizontal) translation of the clavicle [59].
  • The coracoclavicular ligaments consist of the conoid (medial) and trapezoid (lateral) components [59, 65].
  • The coracoclavicular ligaments are the primary stabilizers to superior (vertical) translation of the distal clavicle [59, 65].
  • The trapezoid ligament is located approximately 25 mm from the acromioclavicular joint [70].
  • The conoid ligament is located approximately 45 mm from the acromioclavicular joint and is the stronger of the two coracoclavicular ligaments [70].
  • The superior shoulder suspensory complex is composed of the glenoid, coracoid process, coracoclavicular ligaments, distal clavicle, acromioclavicular joint, and acromion [59].
  • The superior shoulder suspensory complex provides a stable connection between the scapula and the axial skeleton [59].

Pathophysiology and Biomechanics

  • The acromioclavicular joint articulation helps provide a stable base for the glenohumeral joint to position the arm in space [32].
  • Distal clavicle resection does not address instability and may accentuate it when horizontal or vertical instability exists [23].
  • Distal clavicle resection must be reserved for patients in whom the coracoclavicular ligaments are intact and there is no concomitant instability [23].
  • Kinematic changes resulting from acromioclavicular joint dislocation could be a potential source of pain and dysfunction in the shoulder [87].
  • A combined injury of the acromioclavicular and coracoclavicular ligaments significantly alters glenohumeral kinematics during abduction [117].
  • Large kinematic differences exist between the intact state and a Rockwood V lesion during both humerothoracic and scapulothoracic movements [118, 126].
  • The distal clavicle has a wide range of motion during shoulder abduction, which does not support the concept of synchronous motion with the scapula [123].
  • The trapezoid and conoid ligaments have unique functions in normal shoulder kinematics due to their anatomic attachments [86].
  • Scapular and clavicular kinematics are affected in acromioclavicular separation models [89].
  • Type I and II acromioclavicular joint disruptions impair long-term shoulder function in about half of patients 10 years after injury [101].
  • The normal coracoclavicular distance measures approximately 1.1 to 1.3 cm [150].
  • Injury to the acromioclavicular ligaments in a type II injury causes an increase of 3.6 mm in anterior and 6.4 mm in posterior translation [150].

Classification

  • The Rockwood classification system groups similar diagnoses, provides prognostic information, and guides treatment options [147].
  • Studies have shown fair to moderate reliability in the use of the Rockwood classification for classification and surgical decision making [147].
  • The ISAKOS Upper Extremity Committee suggests adding grade IIIA and grade IIIB injuries to a modified Rockwood classification to distinguish between stable type III injuries and unstable grade III injuries with therapy-resistant scapular dysfunction and overriding clavicle [154].
  • In the Rockwood classification, type I is established when 0% to <10% superior displacement of the distal clavicle is found [144].
  • In the Rockwood classification, type II is present when the affected side differs by 10% to ≤25% superior displacement of the distal clavicle [144].
  • In the Rockwood classification, type III dislocation is defined as a coracoclavicular distance difference of >25% to ≤100% compared with the contralateral side [144].
  • In the Rockwood classification, a coracoclavicular distance difference of >100% compared with the contralateral side indicates a type V separation [144].
  • A new classification of AC joint instability defines Group 1 as having a coracoclavicular distance difference ≤30%, which includes all Rockwood type I, type II, and borderline low-grade type III patients [144].
  • A new classification of AC joint instability defines Group 2 as having a coracoclavicular distance difference >30%, which represents high-grade AC joint dislocations including all Rockwood type V patients and the majority of Rockwood type III patients [144].
  • The Rockwood type IV AC injury includes disruption of AC ligaments, disruption of coracoclavicular ligaments, and posterior translation of the clavicle [33].
  • Methods to diagnose both superior and posterior translation of the clavicle need further debate [34].
  • Fractures of the clavicle may be divided into three groups: Group I (middle third), Group II (distal to the coracoclavicular ligament), and Group III (proximal end) [24].
  • Neer classified fractures of the distal end of the clavicle into two types [24].
  • Robinson classified clavicular injuries and defined the lateral one-fifth of the clavicle as Type 3 [52].

Clinical Presentation

Indications and Selection

  • In appropriately selected patients, open or arthroscopic distal clavicle resection is necessary to relieve symptoms [7].
  • Distal clavicle excision must be reserved for patients in whom the coracoclavicular ligaments are intact and there is no concomitant instability [23].
  • When horizontal or vertical instability exists, results of distal clavicle excision are compromised because the technique does not address instability and may accentuate it [23].
  • Operation for acromioclavicular dislocation should be considered only in thin patients with a prominent clavicle, those doing heavy work, or those whose work requires frequent shoulder abduction and flexion [49].
  • For chronic symptomatic acromioclavicular injuries, partial claviculectomy is believed to be the best procedure, offering negligible morbidity and rapid return to function [35].
  • Clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis following acromioclavicular joint dislocation [22].
  • Simple excision of the outer end of the clavicle has yielded satisfactory results in patients with complete dislocation and subluxation, with no residual upward displacement disturbing the patients [2].
  • Routine distal clavicle resection in the setting of rotator cuff repair does not result in improved outcomes for patients, with no difference observed at 24 months post-surgery [11].

Diagnostic Considerations

  • There may be misdiagnosis due to associated or underlying superior labral detachment causing symptoms similar to those of acromioclavicular joint pathology [127].
  • Clinical examination and surgical treatment should address anatomic restoration of individual structures to optimize the mechanical capability of the claviscapular segment [25].

Investigations

Radiographic Evaluation

  • The Zanca view is a special radiographic view indicated for the acromioclavicular joint, performed as an AP with 10° cephalic tilt centered over the AC joint [83].
  • The Zanca view technique requires the patient to be supine and uses only one-half the voltage of a routine shoulder AP view to create a soft-tissue view [83].
  • Weighted stress radiographs significantly increase the measured elevation of the clavicle and the coracoclavicular distance compared to non-weighted views [155].
  • The normal coracoclavicular distance is 1.1 to 1.3 cm [83].
  • Methods to diagnose both superior and posterior translation of the clavicle require further debate [34].
  • Plain radiographs can observe arthritis, calcific tendinitis, and osteolysis of the distal clavicle [82].
  • The axillary view provides good visualization of the coracoid process, acromion, and distal clavicle [83].

Advanced Imaging

  • CT imaging is frequently used to evaluate fractures of the shoulder, assess for bony lesions in recurrent instability cases, or for preoperative templating for shoulder arthritis [82].
  • MRI is the modality of choice for evaluating the rotator cuff, biceps, and subacromial/subdeltoid bursa [82].
  • Ultrasonography is a low-cost alternative to MRI and arthrography for evaluating both skeletal and soft-tissue structures of the shoulder [82].
  • Ultrasonography can provide immediate, real-time visualization of the rotator cuff, biceps tendon, and calcific deposits [82].
  • Ultrasonography is highly operator dependent and is not as useful for evaluating labral tears or rotator cuff tears that are very small or larger than 3 cm [82].
  • Intraoperative ultrasound allows surgeons to safely identify and access the acromioclavicular joint for distal clavicle excision [4].
  • 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 [28].

Treatment

Indications and Contraindications

  • Distal clavicle resection is indicated for symptomatic acromioclavicular joint pathology in appropriately selected patients [7].
  • The procedure is reserved for patients with intact coracoclavicular ligaments and no concomitant instability [23].
  • Results are compromised when horizontal or vertical instability exists because the technique does not address instability and may accentuate it [23].
  • Clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis following dislocation [22].
  • Routine distal clavicle excision is not absolutely necessary, even in patients with symptomatic acromioclavicular joint osteoarthritis [136].

Outcomes and Efficacy

  • Simple excision of the outer end of the clavicle has yielded satisfactory results with no residual upward displacement disturbing the patients [2].
  • 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 [9].
  • 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 [19].

Surgical Technique and Landmarks

  • Portal placement remains paramount in both facilitating surgery and avoiding injury to adjacent extra-articular structures regardless of the technique chosen for distal clavicle resection [1].
  • Intraoperative use of ultrasound and cannulated dilators allows surgeons to perform distal clavicle excisions in a more efficient, reproducible and safer manner [4].
  • Beveling the inferior 20% to 25% of the clavicle to make it co-planar with the decompressed acromion is safe and is not an etiologic factor in acromioclavicular joint pain or instability for appropriate clinical indications [139].

Complications and Revision

  • A 5-mm distal clavicle resection guaranteed no abutment but decreased joint stiffness [29].
  • The early results of clavicular reconstruction after failure of partial excision of the lateral end of the clavicle are encouraging and may be the treatment of choice in patients with excess resection of the clavicle [14].

Complications

  • Incomplete excision and regrowth of the distal clavicle are the most common causes of revision surgery [12].
  • Regeneration of the excised portion of the clavicle occurs frequently and may produce an unacceptable result, with a higher likelihood in younger patients [13].
  • The most common complication of distal clavicle resection is persistent pain, which can result from over- or under-resection [140].
  • Incomplete resection can occur due to poor visualization [140].
  • Overexuberant resection of the clavicle or disruption of the acromioclavicular and coracoclavicular ligamentous system can result in iatrogenic instability of the acromioclavicular joint [140].
  • Posterior translation of the acromioclavicular joint is increased by 32% after a distal clavicle resection with an acromioclavicular capsular incision [140].
  • Posterior translation can be reduced to 13% if the distal clavicle resection is completed with a coracoacromial ligament augmentation procedure [140].
  • Postoperative iatrogenic instability may require revision surgery or coracoclavicular ligament reconstruction [140].
  • Other complications of distal clavicle resection include infection, stiffness, fracture, spontaneous fusion, and complex regional pain syndrome [140].
  • A 5-mm distal clavicle resection guaranteed no bone-to-bone abutment but decreased joint stiffness [29].
  • Distal clavicle excision with 2.5 mm of bone was successful in many specimens, whereas a 5 mm resection guaranteed no bone-to-bone abutment [17].
  • The high failure rate in patients with even subtle acromioclavicular instability is 42% [167].
  • When horizontal or vertical instability exists, results of distal clavicle resection are compromised because the technique does not address instability and may accentuate it [23].

Instability and Dislocation

  • Acromioclavicular dislocation can occur after arthroscopic distal clavicle resection [1].
  • Portal placement is paramount in avoiding injury to adjacent extra-articular structures during distal clavicle resection [1].
  • Distal clavicle resection should be reserved for patients with intact coracoclavicular ligaments and no concomitant instability [23].
  • Clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis following late loss of reduction [22].
  • Simple excision of the outer end of the clavicle yielded satisfactory results with no residual upward displacement disturbing patients [2].

Fractures and Bony Complications

  • Fracture of the distal clavicle or coracoid process after coracoclavicular ligament repair or reconstruction is a rare but serious complication that can occur independent of bone tunnels created during the index procedure [100].
  • Clavicle and coracoid fractures occurred in 1.9 out of 100 cases in a review of operative acromioclavicular joint separations in an active population [161].
  • Retaining the clavicular hook-plate indefinitely carries a potential risk of developing osteolysis and fracture around the implant [51].
  • Subacromial osteolysis is a complication associated with hook plate fixation for acromioclavicular dislocation [163].
  • Hook plates used for lateral clavicle fractures can have complications including rotator cuff tear, impingement pain, and need for removal [52].
  • Clavicular reconstruction after failure of partial excision of the lateral end of the clavicle has encouraging early results and may be the treatment of choice in patients with excess resection [14].

Infection and Other Complications

  • Older patients and females were more likely to experience postoperative complications requiring reoperations, including revision acromioclavicular joint reconstruction, distal clavicle excision, and irrigation and debridement [37].
  • The incidence of complications in operative acromioclavicular joint separations in an active population was 1.35 per 100 person-years [161].

Recovery

Outcomes and Functional Improvement

  • 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 ACJ pathology [18].
  • For chronic symptomatic injuries, partial claviculectomy is believed to be the best procedure, offering negligible morbidity and rapid return to function [35].
  • Clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis [22].
  • 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 [166].
  • Arthroscopic distal clavicle resection has provided more 'good or excellent' results than has the open procedure, but is comprised of low-level evidence [6].
  • Less residual pain was found using the arthroscopic technique compared to the open technique [166].

Return to Activity

  • More than 90% of patients manage to return to driving within 4 weeks and to work within 6 weeks following arthroscopic subacromial decompression and acromioclavicular joint excision [97].

Complications and Revision

  • Older patients and females were more likely to experience postoperative complications requiring reoperations, including revision ACJR, distal clavicle excision, and irrigation and debridement [37].

Key Evidence

  • [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. [1] (10.1016/j.jse.2010.08.032)
  • [L4] Open distal clavicle resection yields good to excellent results in properly selected patients and does not create significant subjective or objective weakness. [3] (10.1016/s1058-2746(10)80006-0)
  • [L5] The technique will allow surgeons to perform distal clavicle excisions in a more efficient, reproducible and safer manner. [4] (10.1016/j.eats.2024.103331)
  • [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. [5] (10.1016/j.arthro.2018.03.004)
  • [L3] Arthroscopic distal clavicle resection has provided more 'good or excellent' results than has the open procedure, but is comprised of low-level evidence. [6] (10.1097/blo.0b013e31802f5450)
  • [L5] In appropriately selected patients, open or arthroscopic distal clavicle resection is necessary to relieve symptoms. [7] (10.5435/00124635-199905000-00004)
  • [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. [8] (10.1016/j.jse.2006.10.006)
  • [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. [9] (10.1016/j.arthro.2009.12.007)
  • [L2] Routine distal clavicle resection in the setting of rotator cuff repair does not result in improved outcomes for patients with no difference being observed at 24 months post surgery. [11] (10.1177/1758573217741124)
  • [L4] Incomplete excision and regrowth of the distal clavicle are the most common causes of revision. [12] (10.1016/j.arthro.2009.06.010)
  • [L4] Regeneration of the excised portion of clavicle occurs frequently and may produce an unacceptable result, and may be more likely to occur in the younger patient population. [13] (10.1016/s1058-2746(05)80049-7)
  • [L4] The early results are encouraging and may be the treatment of choice in patients with excess resection of the clavicle. [14] (10.1016/s1058-2746(95)80128-6)
  • [L4] Horizontal instability of the clavicle is evident with distal clavicle resection of greater than 10 mm. [15] (10.1016/j.xrrt.2021.05.003)
  • [L4] Excision of the outer end of the clavicle is preferred for old dislocations, while open reduction and internal fixation are not recommended due to complications and poor functional results. [16] (10.2106/00004623-196345080-00024)
  • [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. [17] (10.1016/j.jse.2007.02.105)
  • [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. [18] (10.1016/j.jseint.2023.07.014)
  • [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. [19] (10.1177/0363546506294855)
  • [L4] The technique was validated using cadaveric dissection and yields a method of establishing the anterior portal for distal clavicle excision with a safe corridor for placement of instruments in a reliable manner that does not disrupt the important stabilizers of the glenohumeral or AC joints. [20] (10.1097/bte.0000000000000033)
  • [L3] Late loss of reduction was common, and clavicular resection reliably produced significant improvement in patients with persistent pain or posttraumatic arthritis. [22] (10.2106/00004623-198769070-00013)
  • [L5] [23] (10.5435/00124635-200904000-00002)
  • [L4] [24] (10.2106/00004623-196749040-00024)
  • [L5] Clinical examination and surgical treatment should address anatomic restoration of individual structures to optimize the mechanical capability of the claviscapular segment. [25] (10.5435/jaaos-d-24-00360)
  • [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. [28] (10.1016/j.jse.2021.10.013)
  • [L5] A 5-mm distal clavicle resection guaranteed no abutment but decreased joint stiffness. [29] (10.1016/j.arthro.2007.07.004)
  • [Paper] [32] (10.1097/bte.0000000000000044)
  • [L4] [33] (10.1016/j.arthro.2016.06.013)
  • [L4] Methods to diagnose both superior and posterior translation of the clavicle need further debate. [34] (10.1016/j.jseint.2019.11.006)
  • [L4] Older patients and females were more likely to experience postoperative complications requiring reoperations, including revision ACJR, distal clavicle excision, and irrigation and debridement. [37] (10.1007/s00167-016-4206-y)
  • [L3] This records review found that 10 of 894 (1.1%) rotator cuff repairs underwent subsequent distal clavicle resection. [40] (10.1177/2325967119844295)
  • [L1] Operation should be considered only in thin patients with a prominent clavicle, those doing heavy work, or those whose work requires frequent shoulder abduction and flexion. [49] (10.2106/00004623-198668040-00011)
  • [L5] Retaining the clavicular hook-plate indefinitely carries a potential risk of developing osteolysis and fracture around the implant. [51] (10.1016/j.injury.2004.08.010)
  • [L4] [52] (10.1177/1758573214536535)
  • [L5] The trapezoid and conoid ligaments have unique functions in normal shoulder kinematics because of their anatomic attachments. [86] (10.1016/j.arthro.2009.12.031)
  • [L5] The kinematic changes could be a potential source of pain and dysfunction in the shoulder with AC joint dislocation. [87] (10.1177/0363546512458571)
  • [L5] Scapular and clavicular kinematics were affected in AC separation models. [89] (10.1016/j.jse.2013.01.004)
  • [L3] The results obtained in the present study suggest that more than 90% of the patients manage to return to driving within 4 weeks and to work within 6 weeks following arthroscopic subacromial decompression and acromio-clavicular joint excision. [97] (10.1111/j.1758-5740.2010.00048.x)
  • [L4] Fracture of the distal clavicle or coracoid process after CC ligament repair or reconstruction is a rare but serious complication that can occur independent of bone tunnels created during the index procedure. [100] (10.1177/03635465211036713)
  • [L4] Type I and II acromioclavicular joint disruptions impair long-term shoulder function in about half of patients 10 years after injury. [101] (10.1177/0363546508319047)
  • [L5] A combined injury of the AC and CC ligaments significantly alters GH kinematics during abduction. [117] (10.1186/s12891-016-1330-2)
  • [L5] There are large kinematic differences between the intact state and a Rockwood V lesion not only during humerothoracic, but also during scapulothoracic movements. [118] (10.1016/j.jse.2022.01.096)
  • [L5] The distal clavicle had a wide range of motion during shoulder abduction, which did not support the concept of synchronous motion with the scapula. [123] (10.1016/j.arthro.2012.04.001)
  • [L5] Large kinematic differences were seen between the intact state and a Rockwood V lesion not only during humerothoracic movements but also during scapulothoracic movements in the cadaveric model. [126] (10.1177/03635465211053016)
  • [L4] The successful treatment of 15 patients by SLAP lesion repair after initial distal clavicle resection indicates that there may be misdiagnosis due to associated or underlying superior labral detachment causing similar symptoms. [127] (10.1016/s1058-2746(96)80319-3)
  • [L2] Routine distal clavicle excision is not absolutely necessary, even in patients with symptomatic ACJ osteoarthritis. [136] (10.1007/s00167-020-06098-y)
  • [L4] We conclude that for appropriate clinical indications, beveling the inferior 20% to 25% of the clavicle to make it co-planar with the decompressed acromion is safe and is not an etiologic factor in acromioclavicular joint pain or instability. [139] (10.1067/mse.2000.109560)
  • [L5] [140] (10.1177/0363546513485359)
  • [L1] [144] (10.1016/j.jse.2020.10.026)
  • [L5] The Rockwood classification system groups similar diagnoses, provides prognostic information, and guides treatment options, though studies have shown fair to moderate reliability in its use for classification and surgical decision making. [147] (10.1007/s11999-016-5079-6)
  • [L5] [150] (10.1016/j.jse.2010.10.030)
  • [L5] The ISAKOS Upper Extremity Committee suggests adding grade IIIA and grade IIIB injuries to a modified Rockwood classification to distinguish between stable type III injuries and unstable grade III injuries with therapy-resistant scapular dysfunction and overriding clavicle. [154] (10.1016/j.arthro.2013.11.005)
  • [L4] Weighted stress radiographs significantly increased the measured elevation of the clavicle and the coracoclavicular distance compared to non-weighted views. [155] (10.1016/j.jseint.2023.06.011)
  • [L3] This review demonstrated an incidence of 1.35 complications per 100 person-years, with clavicle and coracoid fractures occurring in 1.9 out of 100 cases. [161] (10.1177/2325967121s00330)
  • [L1] The current analysis suggests coracoclavicular ligament reconstruction as an effective surgical approach for decreasing the incidence of subacromial osteolysis. [163] (10.1016/j.jse.2024.03.018)
  • [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. [166] (10.1177/0363546511419633)
  • [L4] The high failure rate in patients with even subtle acromioclavicular instability (42%) suggests that in these cases formal stabilization with ligament reconstruction should be considered in addition to resection of the distal clavicle. [167] (10.1016/s1058-2746(10)80007-2)

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c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.