1.1 Epidemiology

In adults, between 2.6 and 5% of all fractures involve the clavicle. The middle third of the clavicle is involved in more than 66% of these injuries, followed by lateral third fracture in approximately 25%, and medial third fracture in 3%. A bimodal distribution exists with fractures occurring more often in male patients younger than 30 years and a smaller peak for patients older than 70 years [2].

1.2 Special characteristics

The goals of treatment for clavicle fractures include reduction of pain and restoration of shoulder function. Nonoperative treatment remains the mainstay of treatment in most fractures. This consists of sling treatment in the acute period, followed by early range-of-motion and strengthening exercises as the pain subsides, generally after 2–6 weeks. The use of a figure-of-eight bandage should be discouraged, as it offers no benefits and can be complicated by axillary pressure sores and higher rates of nonunion [3].

2.1 Case history and physical examination

Clavicular fractures result from falls with direct impact on the point of the shoulder, typically from outdoor sporting activities in younger patients and simple falls in older patients. It is crucial to determine the mechanism of injury. High-energy falls can be associated with injuries to the head and chest, whereas fractures after minimal trauma may result from a pathological fracture. Traction-type injuries require early and careful exclusion of scapulothoracic dissociation, neurological and vascular injuries. Clinically, patients exhibit swelling and ecchymosis, with deformity and tenderness localized to the fracture site ( Fig 6.1.2-1a ). Soft-tissue tenting should be noted as this may produce skin necrosis and ulceration ( Fig 6.1.2-1b ).

2.2 Imaging

Most clavicular fractures are diagnosed on a simple AP view ( Fig 6.1.2-2a ). A 20° cephalic tilt view eliminates the overlap of the thoracic cage. These x-rays should be taken with the patient upright to better demonstrate fracture displacement ( Fig 6.1.2-2b ). Weight-bearing stress views can help to assess the integrity of the coracoclavicular ligaments in lateral injuries involving the distal clavicle or acromioclavicular joint. Computed tomography is indicated in complex shoulder girdle injuries, and also improves visualization of the medial end of the clavicle and sternoclavicular joint when injuries are suspected at this site. Chest x-rays are useful to exclude associated chest injuries, assess for shortening by comparing with the contralateral clavicle, and exclude scapulothoracic dissociation.

4.1 AO/OTA Fracture and Dislocation Classification

The clavicle is designated as bone 15. It has three locations: 15.1 (proximal [medial]), 15.2 (diaphyseal), and 15.3 (distal [lateral]). The proximal (medial) and distal (lateral) end segments are divided into types A (extraarticular), B (partial articular), and C (complete articular). The diaphyseal segment is divided into types A (simple), B (wedge), and C (multifragmentary). However, the AO/OTA Fracture and Dislocation Classification presently has limited therapeutic and prognostic value, as it does not take into account the degree of displacement of the fracture.

4.2 Other key classification systems

The Allman classification is based on the location of the fracture (I: middle third, II: lateral third, III: medial third) [4]. Neer [5] specifically classified lateral third fractures, emphasizing the importance of the coracoclavicular (CC) ligaments: type I occurs distal to the CC ligaments with minimal displacement of the medial fragment; type II involves the CC ligaments and results in superior displacement of the medial fragment; type III extends into the acromioclavicular joint, with intact CC ligaments. Craig [6] combined the Allman and Neer classification systems and added subgroups for pediatric and multifragmentary fractures to the medial and lateral groups.

The Edinburgh Classification is a comprehensive system developed by Robinson [2] after analyzing 1,000 clavicle fractures. It is the first system to classify shaft fractures according to their displacement and degree of comminution. Type 1 fractures involve the medial end, type 2 the shaft fractures, and type 3 the lateral end. The shaft fractures are divided into types A and B, depending on their presence or lack of cortical contact. Type 2A fractures are further subdivided into undisplaced (type 2A1) and angulated (type 2A2), while type 2B fractures are subdivided into simple or wedge (type 2B1) and multifragmentary (type 2B2). The medial and lateral end fractures are subdivided into subgroups 1 and 2 depending on the involvement of the adjacent joint.

5.1 Shaft fractures

There is controversy regarding the surgical indications in acutely displaced shaft fractures. The traditional belief that most midshaft fractures heal without functional deficit has been called into question by several prospective studies [7–11], which reported higher nonunion and symptomatic malunion rates (15–20%), lower functional scores as well as residual weakness with nonoperative treatment. Other studies [2] have suggested that specific fracture types with displacement of more than a clavicular width or significant comminution are at risk for poorer outcomes. A retrospective series [12] of 52 nonoperatively treated patients showed that initial shortening of 2 cm or more was predictive for nonunion and poorer results.

On the other hand, the surgical group is associated with a higher complication and reoperative rate, largely due to hardware-associated problems. Some [13] have therefore cautioned against overtreatment of all displaced midshaft clavicular fractures. With the current lack of consensus regarding which displaced fracture should receive surgical treatment, adequate counseling concerning the risks involved and expected outcomes is crucial.

5.2 Lateral-end fractures

Most fractures involving the distal clavicle are undisplaced and extraarticular. These generally progress to uncomplicated healing. Displaced fractures are associated with a high rate of nonunion (approximately 30%). However, data from several small studies suggest that radiographic nonunion does not always result in clinically important symptoms. It is therefore recommended that surgical treatment for displaced distal clavicular fracture be undertaken on a case-by-case basis [14].

5.3 Medial-end fractures

These fractures are usually managed nonoperatively unless significant posterior displacement produces mediastinal compromise.

6.1 Timing of surgery

Where there is an absolute indication for surgery, it should be undertaken without delay. For relative indications, delaying surgery beyond 2–3 weeks may impair the ease of fracture reduction, especially when closed reduction and fixation with percutaneous techniques is planned.

6.2 Implant selection

Fixation of the clavicle can be achieved using either intramedullary or extramedullary devices. Historically, intramedullary nailing of shaft fractures typically utilized stiff-threaded pins but was associated with a small but significant rate of severe complications due to pin migration into the thoracic cavity. More recently, titanium elastic nails inserted from a medial entry point have been used for simple mid-shaft fractures ( Fig 6.1.2-4 ). These implants cannot be locked although newer devices with this facility have recently become available [15].

The implants most commonly used for plating were the dynamic compression or reconstruction plates 3.5. The use of reconstruction plates facilitates contouring of the implants to the challenging shape of the clavicle ( Fig 6.1.2-5 ). However, they are susceptible to deformation, which can lead to malunion or implant failure. Anatomically precontoured locking compression plates (LCP) have been developed for the clavicle, but it is vital to appreciate the great variability in the shape of the clavicle and the need for further intra-operative contouring to avoid hardware prominence. Locking head screws are an option for use in lateral fractures with a short-end segment and in elderly patients with osteoporotic bone. Biomechanical studies [16] have shown locked plate fixation to be superior although clinical studies are still limited. A 2.7 mm screw or even 2.4 or 2.0 mm screws allow lag screw fixation of smaller, intermediate fragments to achieve anatomical reduction and fixation with absolute stability.

For displaced lateral-end fractures, precontoured anatomical plates have been introduced to allow insertion of more locking screws into the distal fragment. For fractures where the distal fragment is too small to provide reasonable screw purchase, clavicular hook plates have an offset lateral hook to engage the posterior aspect of the acromion. Techniques derived from the surgical treatment of acromioclavicular joint dislocations, such as coracoclavicular screws, suture and sling techniques, or suture tightropes can provide useful adjuncts to the primary fixation or serve as the primary reconstruction.