According to various publications, the incidence rate of post-traumatic nasal deformities varies from 9% to 62% [7] .

Defined as a displacement of nasal structures from the midline.

When assessing the deviated nose, it is important to determine the components involved in the external deviation. The deformity may involve the bony nose, the cartilaginous bridge, or both. Facial CT scans help us to determine the components involved, as illustrated in Figure 1 , which reflects a nasal deviation due to two components ( Figure 1 ) [8] .

The nose is divided into vertical thirds (upper, middle and lower) and each third is examined in relation to the midline [9] .

If the origin is bony, the projection of the nasal pyramid is deviated to the side opposite the trauma. The tip of the nose remains in place, and the septum follows the displacement of the bony canopy, resulting in an obtuse angle with a vertex opposite to the trauma.

If cartilaginous in origin, they are responsible for displacement of the lower two-thirds of the dorsum and the tip of the nose [10] .

Depressions, bumps and nasal width (either too wide or too narrow) can further complicate them.

They can be classified into three types: simple (rectilinear/globally deviated) illustrated by ( Figure 2 ); or complex “S” or “C” shaped illustrated by ( Figure 3 ) [11] .

A direct frontal impact to the nose produces a telescopic injury in which the bony segments widen or shift in both directions. Consequently, although there is usually limited deviation of the nose, there is often retro-displacement of the bony and cartilaginous dorsum with widening of the bony nasal pyramid. Figure 4 illustrates the compressed nose of our patient who suffered a frontal impact resulting in widening of the nasal pyramid with nasal saddle.

Typically, internal nasal examination shows a severely deformed and telescoped septum [8] .

This is a collapse of the middle arch in relation to the tip and dorsum. This depression is caused by a decrease in the structural support of the cartilaginous (lateral septum and cartilage) or bony (bony dorsum) framework at the level of the soft tissue envelope of the nose [12] .

Progressive loss of septal integrity results in a characteristic saddle-nose deformity, with depression and flaring of the middle arch, loss of support and overrotation of the tip, decreased vertical projection, columella retrogression and widening of the nasal base [13] .

Palpation of the nasal dorsum reveals a lack of resistance in its bony and cartilaginous parts.

In functional terms, the internal and external nasal valves are affected, leading to significant difficulties in breathing [14] .

A patient with a history of nasal trauma also has other associated mid-facial deformities. The patient is often unaware of the deformities, and focuses on the external nasal deformity and/or associated functional disturbances.

These deformities can include structural malposition of the midface (maxillary deviation, which can contribute to nasal base offset) and other problems such as pseudotelecanthus, enophthalmos, orbital malposition and frontocranial deformities [8] .

As shown in ( Figure 5 ), a patient with severe sequelae of facial trauma: telechathus and enphthalmos, maxillary recession, enophthalmos and telecanthus responsible for widening of the nasal root. The management of this patient must take into account all these deformities.

Because of these anomalies, the result of rhinoplasty may be unsatisfactory. Identification of these perinasal and periorbital deformities should be carried out preoperatively, and consideration given to simultaneous surgical repair.

The overall rate of nasal obstruction was 10.5% +/− 5.3%.

Nostril permeability is impaired by: stenosis resulting either from displacement of an unstable fracture, or imperfect reduction during original manipulation; mucous synechiae; septal damage in the form of dislocation and, more rarely, septal perforation; collapse of the internal nasal valves and/or lateral wall. Less frequently, instability of the external nasal valve can also lead to nasal obstruction [4] .

The clinical diagnosis of obstruction is sometimes difficult, as it is determined to some extent by the patient’s subjective feelings about all his or her activities.

Even the rudimentary but widely used sniff test can show large differences in the ease of air passage through the nose on consecutive examinations [15] .

CT scans allow analysis of the entire nasal cavity for posterior lesions.

Consequently, an assessment of functional deformity is essential.

A potential long-term complication following septal trauma is perforation of the nasal septum. Although septal perforations are often discovered during routine consultations, they can lead to symptoms such as nasal obstruction, nasal congestion, epistaxis, chronic purulent discharge or other nasal symptoms. The presence of a septal perforation can lead to chronic rhino-sinusitis [5] .

The overall diplopia rate is 3.1% [7] .

The overall rate of epiphora after nasal trauma is 3.1%.

Epiphora is the result of residual obstruction of the lacrimonasal duct.

Nasal obstructions are responsible for sinusitis or mucoceles, with the risk of oculo-orbital and/or endocranial infectious complications [5] .

The overall rate of olfactory disorders in patients with nasal bone fractures (with or without other fractures) is 37.7% +/− 11.3%.

No significant association was found between the type of fracture and the presence of olfactory disorders [7] .

A simultaneous alteration in taste has been reported.

Impaired olfaction can be explained by:

People with impaired olfactory function may be unable to detect important warning signs such as gas leaks, volatile chemical fumes and fires, and put themselves at increased risk of serious injury or death.

Facial appearance plays an important role in social cognition. Therefore, facial asymmetries in people with nasal deformities are likely a source of emotional and social distress [18] .

The often violent mechanism of the injury, the changes in appearance, the altered self-perception and self-confidence can have a significant impact on daily life. The main sequelae are [19] :

Symptoms last for more than 4 weeks, and can often last for years.

Psychological consequences are difficult to identify and may go unnoticed in a busy clinic, not least because surgeons focus their skills on immediately visible or “fixable” problems [20] .

The interview with the patient should provide information on:

Repairing deformations involves the following steps:

1) exhibition;

2) septal reconstruction;

3) hump removal;

4) osteotomies;

5) topping-up procedures;

6) appropriate internal and external splint.

We remove the hump after repairing the septum using the submucosal tunnels previously created.

The hump is removed extra-mucosally. We use a chisel or a rasp, depending on the amount of bone to be removed.

Extreme caution is required when removing the hump in cases of deviated nose due to skeletal asymmetry.

Resection of the hump takes place in two stages, involving the cartilaginous part and the bony part:

We consider that the ideal resection is made in a single block, encompassing part of the septum, triangular cartilage and proper nasal bones. The bone resection can be completed and regularized using a rasp.

If the hump is discrete or the nasal bones are short, we prefer to use only the rasp for bone resection.

Different reconstruction materials are used in rhinoplasty, we distinguish between [14] :

Alloplasts

Autografts

Homografts

Xenografts

Reconstruction options

An adequate nasal lining is essential for the survival of these grafts.

We treat persistent columellar retrogression by adding a columellar abutment.

Tip misalignments are corrected by advancing and suturing the medial ridge to the columellar abutment. When additional projection is required, tip grafts are used. Once the structural framework has been established and work on the tip performed, dorsal augmentation can be performed in a second stage. Fascia alone, cartilage or cartilage wrapped in fascia can be placed along the back to achieve the desired contour.

Collapse of the lateral nasal wall can be corrected with additional cartilage grafts designed to support the internal and external nasal valve.