Fractures

Fig. 10.1

Robinson classification of clavicle fractures

The Robinson Classification system further has been used to identify risk factors for non-union ([10], Fig. 10.2). Age, sex, degree of displacement and comminution were all associated with non-union. From these relative risks, a calculation tool was produced, in an attempt to predict the risk of non-union.

../images/473070_1_En_10_Chapter/473070_1_En_10_Fig2_HTML.png — Fig. 10.2

Prognostic index for union in mid-shaft clavicle fractures

Prognostic index = [−0.85 × (1 if displaced or 0 if undisplaced)] + [−0.36 × (1 if female or 0 if male)] + [−0.37 × (1 if comminuted fracture or 0 if noncomminuted fracture)] + [−0.01 × (age of patient in years)].

For example, a sixty-year-old woman with a displaced, comminuted diaphyseal fracture (Prognostic Index −2.18) has an approximately 75% projected probability that the fracture will be un-united at 12 weeks and a 45% probability of non-union at 24 weeks; whereas a patient with a prognostic index of −1.05 (for example, a 20-year-old man with a displaced but noncomminuted fracture) has a 40% probability that the fracture will remain un-united at 12 weeks and only a 7.5% probability of non-union at 24 weeks. This suggests that earlier surgery might be beneficial for patients with a lower prognostic index.

10.5 Management

10.5.1 Midshaft (Robinson Type 2)

Undisplaced midshaft fractures (type 2A) can be treated conservatively. They usually unite and patients return to excellent levels of function. Management of the displaced fracture, however, remains controversial. Historic evidence that the majority of fractures heal and patients are satisfied with their outcomes has been challenged with more recent studies suggesting that the non-union rate may be higher and that poorer outcomes may be present with conservatively treated displaced fractures.

10.5.2 Non-operative Treatment

The broad arm sling is the most frequently used non-operative treatment. It has better patient satisfaction scores but identical functional outcomes when compared to the figure of eight bandage [11]. The latter also has a higher rate of non-union. It is important to note that neither sling type can reduce a displaced, shortened fracture and hence will always result in a degree of malunion.

The sling is used for comfort only. As function returns and pain recedes it can be discarded. This normally signifies bone healing and a return to activities.

10.5.3 Primary Operative Treatment

The Canadian Orthopaedic Trauma Association reported the results of a multicentre, randomised, controlled trial for conservative versus operative management for displaced midshaft clavicle fractures. They concluded that operative intervention resulted in better outcomes at all-time points with lower non-union rates [12]. However, a meta-analysis, by the same authors, assessing six randomised controlled studies totaling 412 patients, whilst concluding the superiority of operative over non-operative management, found no significant evidence that the long term functional outcome in the operated group was superior to the non-operative group [1]. A similar large multi-centre UK trial [13] demonstrated that open reduction and internal fixation reduced the rates of non-union in displaced midshaft fractures when compared with non-operative treatment, and that this was associated with better functional outcomes. However, their principal conclusion was that the improved outcome scores resulted largely from the prevention of the non-union, which resulted in much poorer function. There was little functional difference between the groups of surgically and conservatively managed fractures that went on to union. The authors also highlighted the higher complication rates and the greater expense with surgical intervention.

A Cochrane review in 2013 stated that there was limited evidence from RCTs on the relative effectiveness of surgical versus conservative treatment for acute middle-third clavicle fractures [14]. Their conclusions were that treatment should be chosen on an individual basis, after careful consideration of the relative benefits and risks of each modality. It is clear also that patients need to be included in the discussion to explore their expectations and demands.

Our current practice is for undisplaced fractures to be treated conservatively with broad arm sling, and clinical review with radiographs to ensure no further displacement, and progression to union. Displaced fractures are treated on an individual basis. In our practice we attempt to assess the likelihood and impact of a subsequent non-union principally in those patients with clinical or radiological shortening of more than 2 cm and usually with the typical “ptotic” appearance of the shoulder. This group of young, active patients, especially those who plan to return to high-level athletic activities or occupations involving repetitive lifting or overhead activity, are likely to benefit from early surgery in terms of speed of recovery and predictability of outcome. Any intervention should be performed by an experienced surgeon to minimise the risk of complications.

10.5.4 Open Reduction and Internal Fixation

Plate fixation is the most common surgical intervention. Care is taken to preserve the supraclavicular nerve and its branches. Current modern implant technology has allowed the development of anatomically contoured specific clavicle fracture plates with dynamic compression locking screws. These allow anatomical restoration of the bony anatomy, whilst being less prominent and hence reducing the requirement for plate removal. The plates are typically placed on the superior surface of the clavicle, which has been shown to be biomechanically beneficial [15] and requires minimal soft tissue detachment. Lag screw techniques can be used to provide compression and to stabilise butterfly fragments in Type 2B1 and 2B2 injury patterns (Fig. 10.3). Anterior plating can also be utilized and proponents highlight that this approach reduces plate prominence and the need for subsequent removal.

../images/473070_1_En_10_Chapter/473070_1_En_10_Fig3_HTML.jpg — Fig. 10.3

Open reduction and internal fixation of a 2B1 clavicle fracture

Care must be taken to protect the structures in the subclavicular region, as overzealous drilling and tapping could compromise inferior structures. Post-operatively radiographs are obtained and a neurovascular assessment of the limb is performed and documented. A poly sling is applied for comfort and simple pendular exercises are commenced. Most athletes can return to training between 3–6 weeks and competition between 6–12 weeks. Non-union following careful fixation is rare.

10.5.5 Intramedullary Fixation (IM Fixation)

IM techniques have the advantages of using smaller incisions, less dissection and soft tissue stripping, relative protection of the supraclavicular nerves and potentially shorter operating times. Historical techniques using pins or modified nails have had serious reported complications, such as intra-thoracic migration and damage to the underlying structures. These were rigid devices inserted from the lateral fragment. Elastic titanium nails have become increasingly popular for the fixation of many long-bone fractures, particularly in children. They work by providing a three-point fixation in the medulla of the bone and are not prone to the problems of previous nails and pins. It is a relative stability construct that heals by callus. This can be rapid and there is evidence that it is useful in athletes, who seek an early return to sport [16]. There is increasing evidence for their use in clavicular fractures. However, the nails are unable to be statically locked, which results in the implant being axially and rotationally less stable. Therefore, the construct is significantly weaker than plate fixation. In our practice, we use IM fixation in longitudinally stable fractures (simple, displaced, midshaft, Type 2B1), in athletes and adolescents, giving good functional and cosmetic results. The nail tends to be removed at around three-six months.

Our technique involves the use of an antegrade titanium elastic nail. The fracture site is opened via a small incision over the fracture site. The fracture is then reduced under direct vision to confirm longitudinal stability. The nail is then passed retrograde into the medial fragment and out of the anteromedial cortex. The fracture is then reduced and the nail passed antegrade into the distal fragment under fluoroscopic control. The wire is cut short and the wounds closed (Fig. 10.4a–c). The post-operative rehabilitation is the same as for plate fixation.

../images/473070_1_En_10_Chapter/473070_1_En_10_Fig4_HTML.png — Fig. 10.4.

(a) Preoperative film of displaced mid-shaft fracture. (b) 6-weeks post-operation. (c) After removal of nail at 6 months

10.6 Complications of Clavicle Fracture Management

10.6.1 Non-union

Historically, the rate of non-union of clavicle fractures was felt to be low but increasingly the rate has been shown to be more significant. In a large meta-analysis of all series of displaced mid-shaft clavicle fractures between 1975 and 2005, the non-union rate in non-operatively treated fractures was 15.1% compared with just 2.2% in those that were operatively treated [17]. Increasing age, female sex, shortening of greater than 2 cm, complete fracture displacement, smoking history and comminution are considered risk factors. The Robinson calculator in the classification section can be useful in trying to identify those at higher risk of non-union.

Non-unions present with pain, clicking, weakness and restriction of movement. The end result can be a significant reduction in function, affecting work, sport and daily activities. The diagnosis is clinical with radiological confirmation, either with plain radiographs or computed tomography.

In the presence of a symptomatic non-union, our preferred option is an open approach with plate fixation. In hypertrophic non-unions there is normally a failure of mechanical stability leading to a level of movement that precludes conversion of soft callus to hard callus. Rigid fixation should create an environment to promote bone union. In atrophic non-unions then there potentially exists a failure of biology and stability may be causal. Therefore, rigid fixation and biological stimulation is required, either by the process of judet decortication, drilling the medullary canals or bone grafting. The results of plate fixation are reliable and union rates post-surgery are high, and the complication rate is low [18, 19].

10.6.2 Malunion

Clavicular malunions were believed to be of cosmetic interest but functionally they were well tolerated [20, 21]. However, with the advent of patient reported outcome measures it is becoming increasingly apparent that this is not always the case. Symptoms of pain, loss of strength, rapid fatigability as well as cosmetic concerns have all been noted in the literature [22–24].

The shortening and rotational deformity that occurs with a malunion may lead to a number of biomechanical changes. The shortening of the clavicular lever arm of the shoulder leads to relative protraction of the scapula. This may lead to changes in the orientation of the glenoid and reciprocal winging of the scapula. The shortening of the clavicle may also have an effect on the muscle function around the shoulder. The muscle tension can be decreased and balance of the forces around the shoulder altered leading to weakness and decrease in endurance, with patients undergoing fatigue earlier [23, 25]. This may lead to functional problems, particular with overhead activities. It has also been suggested by Hill et al. [22] that an established malunion of the clavicle would lead to abnormal loading at the acromioclavicular and sternoclavicular joint. This, in turn, may lead to symptomatic arthrosis, early pain and decreased patient satisfaction.

Documentation of neurovascular problems and thoracic outlet syndrome has also been recorded following clavicle malunion. This can be due to bony encroachment on the neural structures by callus or fracture fragments. Again, these symptoms can be more profound in the overhead athlete [26].

Symptomatic malunion is uncommon, however if it does occur, the treatment algorithm follows a familiar course with non-operative treatments being utilised first. Patients may benefit from physiotherapy to improve muscle balance and power. However, for those who do not improve with therapy and lifestyle modification then surgery should be considered.

Surgery for malunions involves thorough pre-operative planning, with CT imaging being used to assess the plane for an osteotomy, which is typically in the original fracture plane. The set up for the procedure is similar to a primary approach, the malunion is exposed and a low-energy osteotomy performed. The medullary canals are opened with a drill to promote bony union following fixation and the fracture is reduced with careful attention to re-establishing original length and rotation. Plate fixation is used in a compression mode to create a rigid environment for direct bony healing. The literature suggests that corrective osteotomies can improve the symptoms from a malunion [27, 28].

10.6.3 Lateral-Third Fractures

Lateral fractures of the distal clavicle occur in roughly one quarter of clavicle fractures. They are associated more with the elderly and females, and the mechanism is usually a simple fall. The majority of fractures occur around the coracoclavicular ligament complex and displacement occurs if this is defunctioned. The displaced lateral clavicle fracture has a very high rate of non-union (Fig. 10.5a) and consideration should be given to early fixation to stabilise the coracoclavicular complex (Fig. 10.5b). Surgery can be challenging due to the small quantity of bone stock. Non-displaced injuries, where the ligament complex integrity is maintained, can be managed non-operatively. The non-union rate is relatively high, at roughly a third. However, of these, only a third are symptomatic. Robinson et al. suggested a conservative approach to these injuries, using a sling. In cases of soft tissue compromise or a floating shoulder, a more aggressive surgical approach should be considered.