Las fracturas mandibulares son las fracturas faciales más frecuentes tras las fracturas nasales, y la contusión directa es la causa más habitual. La práctica deportiva es una de las principales causas de lesión maxilofacial, con gran variabilidad según el deporte practicado. Aunque existen diferentes publicaciones sobre el return-to-play en la fractura mandibular, no existe consenso claro al respecto.
Maxillary fractures are the most frequent facial fractures after nasal fractures. Direct concussion is the most frequent cause. Sport related maxillary fractures are frequent, and vary according to the discipline. Many articles have been published with return to practice recommendations, but no consensus has been reached.
Clinical case
We present the case of a 17-year-old male patient who presented at A/E as a result of a facial contusion while playing field hockey. The cause was direct contusion with a hockey stick. The patient had no relevant pathological history or drug allergies.
Physical examination revealed intense pain on palpation of both mandibular bodies, with a deficit on buccal opening. The patient was hemodynamically stable and breathing normally.
A simple X-ray was requested (Fig. 1) which revealed a complete fracture of the right mandibular ramus and a left parasymphyseal fracture. In the absence of emergency orthopantomography, a mandibular CT scan revealed a displaced fracture of the right mandibular angle, with subcutaneous emphysema (Fig. 2) and a non-displaced left parasymphyseal fracture.
Figure1. Full fracture of right mandibular ramus and left parasymphyseal fracture in a 17-year-old field hockey player with direct facial contusion.
Figure 2. Displaced fracture of the right mandibular angle, with subcutaneous emphysema, in a 17-year-old field hockey player with direct facial contusion.
Before the diagnosis of closed mandibular fracture, the patient was sent to the referral hospital, where he underwent open reduction with osteosynthesis plates. The patient resumed contactless sport after three weeks from the fracture and returned to regular contact sport at eight weeks, after evidence of radiological consolidation of the fracture. The patient used face protection during the remaining two months of competition.
Discussion
Mandibular fractures are the most frequent in facial traumatology, after nasal fractures, and are the subject of numerous consultations at Emergency Services.
A total of 17.9% of mandibular traumatisms are associated with other facial injuries and 12% present with dental lesions. The total proportion of maxillofacial fractures accompanied by a mandibular fracture amounts to 49%.1
Sport is one of the main causes of maxillofacial injury (the main cause being traffic accidents). A study in the Dutch population showed that football and field hockey were the sports where most maxillofacial injuries were recorded (although the bias of the most practiced sports in each country should be considered).2
Fracture can be caused by a direct mechanism (at the site of the trauma) or an indirect one (condylar fractures are very frequent in severe symphyseal trauma).
Mandibular fractures are usually localised in regions with weaknesses and where the bone structure has less anatomical resistance (e.g. the mandibular condyle); areas weakened by the presence of retained teeth, wisdom teeth, cysts, long dental roots, mandibular atrophy secondary to edentulism, or pathological history that has weakened the bone). In the child population, the weak points of the mandible are the region of the canine root, the second adult molar, and the neck of the condyle.2
The stability of mandibular fractures depends on their location and trajectory: at a mandibular angle, the fractures whose line follows an anteroinferior trajectory, i.e. downwards and forwards, are considered favourable horizontal fractures, as the fracture tends to stabilise due to the action of the anterior and posterior musculature (masseter and internal pterygoid muscle). In unfavourable vertical fractures the line runs from back to front and inwards.3
Clinical background
In general, they are usually characterised by a deformity of the mandibular arch and, consequently, malocclusion and facial asymmetry (fracture or bone dislocation).
The site of the fracture usually produces an area of painful swelling upon palpation and possible subcutaneous crepitation. It is advisable, as far as possible, to run a physical examination before the appearance of tissue swelling, oedema, ecchymosis or hematoma, since these will make it difficult to reach a correct assessment. Some fracture lines can even be manually mobilised, especially in atrophic jaws. In addition, there is sometimes a tearing of the mucosa and, very occasionally, the surrounding skin.
When there is compromise or a defect of both soft and hard tissue and vascular structures, the surgeon must restore the integrity of facial aesthetic units, tears, lacerations and tissue defects using complex surgical techniques with local or microvascularised flaps, which maintain facial aesthetics and functionality, and complement the treatment of the bone fracture.4
In function terms, altered or displaced occlusion is usually observed with compromised mandibular mobility. Those that affect the condyle or neck of the mandibular condyle are usually characterised by functional joint impotence (impossibility of opening or closing the mouth completely and correctly). Under normal conditions, the opening width of the joint is approximately 35-40 mm (taking the measurement between the edges of the upper and lower central incisors), below 30-35 mm being considered pathological. The oral opening depends on the temporomandibular joint, which, in the first instance makes a rotational movement and secondly slides the jaw forward. The latter movement, with the mouth closed, produces mandibular protrusion, which enables the patient to place the teeth of the lower arch anterior to those of the upper arch. Thus, in order to detect a mandibular fracture, it is very useful to ask the patient about any possible changes in occlusion as well as dental losses secondary to trauma.
Fractures located at any point along the course of the inferior alveolar nerve (mandibular body and angle), which may be affected, are manifested as paraesthesia, dysesthesia or anaesthesia of the lower lip and dental arch.
Fracture or dislocation of a tooth requires that the patient be sent to the dentist without delay, since even in cases of complete avulsion, and if a short time has elapsed (6-8 h), it is possible to replant the tooth successfully, especially in children. The tooth must ideally be preserved in serum, or in milk or saliva if not available.
It is important to emphasize the clinical characteristics of two pathological entities that often arise as differential diagnosis. Firstly, when a patient presents at A/E with mandibular opening and protrusion and is unable to close their mouth, this is usually the result of a jaw dislocation: i.e. the mandibular condyle has been displaced to in front of the tubercle, outside the glenoid cavity. Conversely, secondly, we must remember that the limitation of mandibular movements in the absence of any history of trauma may be secondary to rheumatoid arthritis, congenital bone abnormalities, osteoarthritis involving the temporomandibular joint, or muscle spasm, and anchylosis of soft or bony tissues. For this reason, the cause or precipitating factor of the change in occlusion is decisive for a good diagnosis. While a fracture occurs in pathological bones normally after trauma or simply by eating hard foods, a temporomandibular joint dislocation occurs after opening the mouth wide (yawn).
Radiological examination
If a mandibular fracture is suspected, on the basis of medical background and the clinical examination (facial asymmetry or functional alteration), the diagnosis should always be backed by imaging methods. An efficient radiological study will not only enable adequate diagnosis and treatment but will also enable us to evaluate the postoperative result more efficiently.
For the diagnosis of mandibular fractures, panoramic xray or orthopantomography provides a very good first general view, however in many emergency units such a test is not available. In these situations, simple x-ray imaging with AP projection (Fig. 1), Townes and left and right lateral oblique view usually enables visualisation of the fracture, however in case of apparently normal x-rays and high diagnostic suspicion, mandibular CT (computed tomography) scan should also be requested (Fig. 2). Computed tomography is the optimal study for visualisation of the jaw on all planes, especially the condyles. These are frequently displaced by the traction of the masticatory musculature and become out-of-plane, the reason why sometimes fractures at this level go unnoticed with conventional radiological tests.
NMR (nuclear magnetic resonance) is usually used in the case of suspected meniscal injury of the temporomandibular joint.
Emergency treatment
Jaw fractures are often seen as a further condition in polytraumatised patients where a vital compromise may coexist. The presence of craneo-encephalic trauma, vertebral fractures or spinal cord injuries, haemorrhages, airway obstruction, infections, chest or abdominal trauma, or long bone fractures are all associated life-threatening injuries and sometimes require resuscitation manoeuvres (ABCDE assessment). The airway must be checked and free of foreign bodies that obstruct it, such as broken or avulsed teeth, bone fragments, vomit, blood, or even the tongue retruded, to allow proper ventilation.
We must be able to distinguish whether the patient is breathing spontaneously, or if he has respiratory arrest or obstruction that requires artificial ventilation (orotracheal, nasotracheal or emergency tracheotomy). In addition, the patient should be hemodynamically stabilised and blood circulation should be ensured, for which we will have to control bleeding (ligation, pressure, tamponade), stabilise the fractures as much as possible to reduce volume losses, and maintain good blood pressure.
Mandibular fractures are painful and should be treated, as far as possible, urgently. If fracture reduction is deferred excessively, we run the risk of an organised hematoma that subsequently impedes correct reduction.5 In addition, certain unstable bifocal fractures may produce posterior traction of the mandibular symphysis/body and thus compromise the airway. Surgical treatment of the bone fracture site depends on its course and location and the patient’s history, however open reduction and stabilisation is usually performed with osteosynthesis material. Occasionally, treatment requires an intermaxillary block for a variable period of time. Wound flushing will be carried out for debridement and cleaning, and to minimise microbial contamination.
Due to the fact that many of these fractures are open (either to the skin or in the mouth) antibiotic treatment with amoxicillin / clavulanic, clindamycin or a first-generation cephalosporin should be given. Due to secondary soft tissue oedema, the use of corticosteroids as anti-inflammatory drugs is common (provided there are no medical contraindications or any contravention of anti-doping legislation).
Return to practice
The literature reflects the pressure exerted on sports doctors to return athletes as early as possible to play. However, there is little scientific evidence on the return to play in patients with facial fractures. This situation points to the need to formulate protocols based on scientific evidence for return to sport after facial trauma.
Different studies have shown that bone healing begins with an inflammatory reaction phase (at 5 days of fracture), followed by a bone callus formation phase (between 4 and 40 days after fracture), and finally a bone remodelling phase (25-50 days after fracture). Complete ossification of the fracture is verified by radiological tests.6,7
Based on these phases, we propose the following algorithm for return to play:
— Do not take physical exercise within 15 days of fracture reduction.
— Light practice with no physical contact between 15 and 30 days after treatment of the fracture.
— Normal practice with no contact between 31 and 40 days after fracture.
— Play with contact and real game from day 41, with facial protection.
It should be emphasized that this plan for return to play must be adapted individually, depending on the characteristics of the particular fracture, its location, the treatment applied and the stability achieved; the pathological and physiological background of the patient and the type and category of the sport practiced. In addition, the following guidelines should be considered:
— In combat sports, return to sport is not recommended until 3 months.8,9
— In patients with risk of new facial contusion, the removal of the osteosynthetic material (if not resorbable) should be considered when the bone at the fracture site has consolidated.
— Any player who returns to play prior to complete bone healing with radiological evidence should wear a protective mask.
The Fowel and Earl team reported return to play at 3 weeks of facial trauma, but there is still insufficient scientific evidence to support this reduction in time to return to play.7
Another factor that should be considered is psychological recovery. Players should regain confidence before returning to sport. A physically cured player may not be mentally recovered from the trauma caused by the injury, and this condition involves a greater risk of further injury. This situation has been described especially in baseball batters. Psychological recovery of facial fractures requires training and controlled situations, which enable the player to regain confidence. The collaboration of a sports psychologist may be necessary.10
Prevention
A review by Laskin found that over 100,000 sports-related injuries could be prevented annually using adequate head and face protection.11 Other studies have shown that the incidence of facial fractures has declined substantially since the introduction of compulsory use of helmets and face shields in certain sports.
In some contact sports the use of protective helmets is already widespread or obligatory (ice hockey and line hockey); in other sports they are only used in special situations (baseball batters or penalty-corner in field hockey). In other sports the use of protection is optional, although this has become generalised mainly in lower categories.12
Regarding mouth guards, their use has been shown to decrease mandibular fractures in field hockey players, and their use is increasingly widespread, although they are not mandatory.13
In 2011, the use of protective goggles was introduced in the US for lower-level hockey players. This has brought a decrease in the incidence of facial, orbicular and ocular injuries, although it is not proven that this decreases the incidence of contusions.14
Received 14 June 2016;
accepted 11 July 2016
* Corresponding author.
E-mail address: bernatdepablo@gmail.com (B. de Pablo Márquez).
