The saddle nose deformity results from a disruption in the nose’s integral support mechanisms. Reconstructive surgeons must not only reestablish facial aesthetic contours but also rebuild the nose’s structural framework while preserving or restoring nasal function. The causes and the classification of saddle nose deformities are reviewed, and the preferred techniques of correction and reconstruction are illustrated.
Collapse of the middle vault in relation to the tip and dorsum results in a characteristic saddle nose deformity, which presents significant reconstructive challenges. First recognized in the midnineteenth century as resulting from nasal septal perforations, the saddle nose involves a complex interplay of middle vault support structures (primarily the septum and upper lateral cartilages) and their junctions with the bony dorsum and lower lateral cartilages. Understanding of the pathophysiologic process producing the saddle nose deformity permits effective surgical intervention to reverse the mechanical forces responsible for middle vault collapse and to camouflage its associated cosmetic deformity.
The structural support of the nose
Nasal structural integrity is maintained by a network of bony and cartilaginous structures connected to each other by dense fibrous tissue and lined internally by a flexible mucoperichondrium. Considered from the viewpoint of a mechanical construction, the nasal foundation or skeletal base consists of the nasal bones, bony septum, pyriform aperture, and the nasal floor. The septal cartilage firmly interlocks with the nasal bones and bony septum to form a “support wall” for the middle vault and the nasal tip. The upper lateral cartilages that make up the “roof” of the middle vault articulate firmly with this support wall and are primarily supported by this wall, although they receive secondary support from their articulations with the nasal bones and lower lateral cartilages. Similarly, despite collaboration from multiple forces as described by Tardy and colleagues, nasal tip projection relies ultimately on the septal support wall. Although the inherent strength of the upper lateral cartilages and tip may temporarily prevent collapse of the middle vault or roof, an inherent weakness or injury to the septal support wall results in progressive collapse of the middle vault and deformity of distal tip structures. The roof eventually falls in. Critics of this analogy argue that the entirety of this septal cartilage is not necessary to ensure its function. Technically, a door may be placed in a support wall; however, the door must be buttressed on either side and across its top by more substantial columns and beams to ensure structural integrity. Similarly, a 1-cm L-shaped strut of septal cartilage can support the middle vault and tip only if its inherent mechanical properties can resist injury, gravity, and the ravages of time.
The cartilaginous septum’s support of the middle vault and tip helps to define the cross-sectional areas critical for adequate nasal breathing. The internal nasal valve bounded by the junction of the upper lateral cartilages with the septum regulates nasal airflow. Accordingly, small changes in this angle result in significant perturbations of airflow. Loss of septal support may also influence the function of the external nasal valve by altering the relationships among the columella, soft triangle, and nasal ala. Progressive weakening of the septal support wall results not only in a cosmetic saddle nose deformity but also in a corresponding loss of nasal function.
Definition
The saddle nose deformity results from a depression caused by a decrease in the structural support of the cartilaginous or bony framework deep to the nasal soft tissue envelope. The septum’s articulation with the upper lateral cartilages of the nose and its contribution to tip support through the medial crura of the lower lateral cartilages play an integral part in the cause of the deformity and its correction. Clinicians may use the septal support test to indirectly gauge the strength and stability of the septum by applying force directly to the supratip area. Progressive loss of septal integrity results in a characteristic saddle nose deformity, with depression and splaying of the middle vault, loss of support and overrotation of the tip, decreased vertical projection, retraction of the columella, and widening of the nasal base. Functionally, the internal and external nasal valves are affected, leading to significant difficulties in breathing ( Fig. 1 ).
Definition
The saddle nose deformity results from a depression caused by a decrease in the structural support of the cartilaginous or bony framework deep to the nasal soft tissue envelope. The septum’s articulation with the upper lateral cartilages of the nose and its contribution to tip support through the medial crura of the lower lateral cartilages play an integral part in the cause of the deformity and its correction. Clinicians may use the septal support test to indirectly gauge the strength and stability of the septum by applying force directly to the supratip area. Progressive loss of septal integrity results in a characteristic saddle nose deformity, with depression and splaying of the middle vault, loss of support and overrotation of the tip, decreased vertical projection, retraction of the columella, and widening of the nasal base. Functionally, the internal and external nasal valves are affected, leading to significant difficulties in breathing ( Fig. 1 ).
Etiology
Various pathologic conditions can lead to a saddle nose deformity, but trauma and prior surgical procedures account for most causes in the reported literature. Nasal trauma may result in mechanical disruption of the septum or in hematoma formation leading to necrosis of the cartilaginous septum and loss of support. Surgical disruption of septal attachments to the nasal floor, bony septum, and nasal bones, and injudicious resection of the septal cartilage may result in a saddling of the nasal dorsum, although such effects may be delayed for months or years following the procedure. Destruction of the septal mucoperichondrium and subsequent perforation of the septum by prolonged topical use of such vasoconstrictive agents as cocaine and oxymetazoline also commonly result in saddle nose deformities.
Although the cause of a saddle nose deformity may appear evident from the patient’s history, a thorough serologic evaluation, CT, and nasal biopsy are required to exclude conditions such as Wegener’s granulomatosis, sarcoid, Crohn’s disease, and relapsing polychondritis. Such illnesses usually result in damage to the septal and middle vault cartilages and involve the bone to a lesser extent. Directed nasal biopsy permits evaluation for neoplastic processes such as inverted papillomas and squamous cell carcinomas in which direct growth of the lesion is locally destructive. Before the popularization of septorhinoplasty, infectious processes were the most frequent cause of saddle nose deformity and included syphilis, leprosy, and septal abscesses.
Classification
Numerous classification systems describe the manifestations of a saddle nose deformity. In 1949, Seltzer introduced the system of Joseph, categorizing saddle nose deformities into three types. Type I deformities involved depressions of the middle vault without a loss of the structural support or overlying skin. When a loss of structural support occurred, but no change in nasal length was observed, the deformity was categorized as a type II deformity. Type III deformities required complex reconstructions due to loss of nasal length and support.
Tardy and colleagues also proposed a three-tier classification. Mild deformities included those with a depression of the supratip greater than 1 to 2 mm relative to the tip but no loss of structural integrity. Moderate cases revealed a loss of the quadrangular cartilage, dorsal height, and columellar retraction, whereas severe cases also included major septal deformities and nasal twisting.
Daniel and Brenner introduced a more detailed classification system in 2006 that classified saddle nose deformities into six different types based on clinical findings and pathophysiologic processes. Such a categorization allows a more detailed analysis for reconstructive planning ( Fig. 2 ).
Type 0 Deformity: Pseudosaddle
Also termed the pseudosaddle, a type 0 deformity represents a relative depression of the cartilaginous dorsum relative to the bony dorsum. Such depressions may arise naturally or as a result of overresection of the cartilaginous middle vault or overaugmentation of the bony dorsum. Although relatively low, the septal support wall remains solid and the septal support test is always negative ( Fig. 3 ).
Type I Deformity: Minor—Cosmetic Concealment
A type I deformity exhibits some minor decrease in septal support, but demonstrates greater supratip depression and columellar retraction. As in a type 0 deformity, the process leading to weakening of the septum has ceased. Augmentation of the dorsum and the columella with soft tissue such as fascia or diced cartilage can effectively restore nasal balance ( Fig. 4 ).
Type II Deformity: Moderate—Cartilage Vault Restoration
With progressive weakening of the septal support wall, a type II deformity results. The cartilaginous middle vault begins to collapse and the columella retracts as the nose is “saddled from below.” A loss of tip support is concurrently present. Complaints of nasal obstruction secondary to internal nasal valve collapse are common. The reconstruction of the septal support wall and reconstitution of its relationships to the upper and lower lateral cartilage are required to restore nasal valve function and the dorsal contour ( Fig. 5 ).
Type III Deformity: Major—Composite Reconstruction
A type III deformity results in obvious flattening and depression of the middle vault. Damage to the septal support wall such as a nasal septal perforation or disarticulation from the nasal foundation drops the septal dorsum and its attached roof, which splays as the upper lateral cartilages are held up only by their articulation with the nasal bones. The nasal tip begins to rotate upward as the columella retrudes and caudal septal support is lost. Reconstruction must first address the loss of integrity by the septal support wall. Following the re-establishment of a stable support wall, the upper lateral and lower lateral cartilages often require further bolstering to maintain the compromised internal and external nasal valve. The dorsal contour can be effectively restored only after this new structure is established ( Fig. 6 ).
Type IV Deformity: Structural Reconstruction
A type IV deformity often precludes re-establishment of a normal septal support wall due to a large septal deformity and a concomitant defect in the bony vault. The middle vault is depressed and splayed, altering the configuration of the internal nasal valve. Columellar retrusion coupled with overrotation and deprojection of the nasal tip results in a short nose. The ala are consequently splayed so that the alar base is widened and the external nasal valve is compromised. An associated loss and contracture of the nasal lining complicates reconstructive efforts. Functional obstruction results from a multitude of defects including septal perforation, internal valve collapse, external valve collapse, and compromised nasal mucosal function ( Fig. 7 ).
Type V Deformity: Catastrophic—Major Reconstrcution
Daniel described type V deformities as “catastrophic” defects requiring total reconstruction of the internal lining of the nose and the bony and cartilaginous nasal vault. Tissues adjacent to the nose are also affected and require attention. Typically, a large flap such as a paramedian forehead flap is required to cover any new framework that is laid down ( Fig. 8 ).
Reconstructive materials
Alloplasts
Nasal augmentation with alloplastic materials such as leather and ivory was advocated as early as the nineteenth century. Ideally, a nontoxic and nonallergenic alloplastic material would be easy to sculpt and sterilize and would resist resorption and rejection. Rigid plastics gave some early hope for alloplastic grafting. They were well tolerated in the body and were nonimmunogenic, but if they became infected, they were subject to extrusion. Furthermore, their hard surface was difficult to mold and gave the nose a hard consistency that could shift with trauma.
Due to their inert biologic properties, silicone implants remain widely used in dorsal augmentation, especially in Asia. A fibrous capsule surrounds these smooth implants that do not integrate with the adjacent tissue and are therefore prone to shifting and buckling ( Fig. 9 ). Proponents of these implants refer to their ease of use and, if revision is necessary, their ease of removal. Tham and colleagues retrospectively analyzed 355 patients in which silicone implants were used for nasal augmentation and concluded that silicone was effective, economical, and safe for surgical correction of the Asian nose with its thicker soft tissue envelope. It is unfortunate that follow-up averaged just over 4 months and removal or replacement of the implant was necessary in 7.8% of patients. Longer-term studies have also reported higher extrusion and infection rates ( Fig. 10 ).
