BONE GRAFTS USED IN NASAL

RECONSTRUCTION

Presenter – Dr. Pulkit Agarwal

INTRODUCTION

Nasal surgery involves a wide spectrum of procedures ranging from cosmetic rhinoplasty to total nasal reconstruction.

Reconstruction of the nasal skeletal framework is frequently necessary in patients like with congenital or traumatic deformities.

This support is best obtained using bone or cartilage.

HISTORY

VON WALTER (1821) – Autogenous Bone Graft Autogenous corticocancellous bone grafts to

reconstruct lost parts of the maxillofacial skeleton.

These grafts can be used to augment the severely atrophic edentulous alveolar ridges, to reconstruct alveolar defects in cleft palate patients, or to bridge defects that are the result of ablative surgery or trauma.

Autogenous bone grafts, when adequately fixed, usually adapt to the recipient site and incorporate well into the defects.

A layer of connective tissue will cover the grafts while from the interface between the recipient bone and the graft revascularization takes place ultimately leading to the formation of new bone.

Fresh autografts contain surviving cells and inductive proteins, which can stimulate osteogenesis.

Autogenous grafts considered best as : Nonimmunogenic Partially retains its viability immediately after

transplantation

WHY ALTERNATIVES ????

Limited availability The sometimes unpredictable resorption The need for a second operation site The time consuming procedure Donor site morbidity The quantity of bone available Increased costs of hospitalization

MECHANISMS OF BONE GRAFT HEALING

Many factors influence healing process, which may also be considered as a kind of bone regeneration.

Factors like : Bone metabolism Changes in hormonal balance External influences that are present for a prolonged

time. Revascularization is mandatory for graft healing as

newly formed blood vessels enable nutrients and humoral substances to be brought into the graft.

MECHANISMS OF BONE HEALING

If revascularization is successful new bone is formed around the transformed osteocytes at the margins of the graft and the old bone is slowly replaced.

This process is called ‘Creeping Substitution’

WHICH TYPE OF BONE IS SUPERIOR ???

Cancellous bone – Easy capillary penetration. Cortical bone – Volumetric maintainence. So Corticocancellous bone is best. Differences in healing between several

corticocancellous donor sites are related to the 3D osseous architecture ( The Cortical / Cancellous ratio)

TYPES OF GRAFT MATERIAL Per definition there are five types of grafts, i.e.

1. Autografts

2. Isografts

3. Allografts

4. Alloplasts

5. XenograftsThe term autograft refers to tissue transplanted from

one site to another within the same individual.

It can be cortical, cancellous or corticocancellous.

Most common sites for corticocancellous grafts are Typical donor sites are rib, iliac crest, fibula or radius, elbow, mastoid whereas oral sites include chin, retromolar area and mandibular body.

Allografts are obtained from cadavers or living individuals from the same species. In human medicine they can be obtained from tissue banks (KÜBLER 1997).

There are three types of bone allograft available:

Fresh or fresh-frozen bone

Freeze-dried bone allograft (FDBA)

Demineralized Freeze Dried Bone Allograft (DFDBA)

The most commonly used allograft is DFDBA. Demineralized bone matrix minimises antigenicity. Because allografts are not osteogenic, bone formation

takes longer and results in less volume compared to autogenous grafts .

They revascularize quickly but the risk of an antigen transmission, especially in a high vascular area as the facial skeleton, increases the risk of rejection of the graft.

So in oral and maxillofacial area demineralized bone grafts can be used after irradiation.

Alloplasts are synthetic materials consisting of biological inert substances. (eg Tricalciumphosphate and Hydroxyapatite, Bovine Bone Mineral (BBM), Coralline, Active glass ceramics).

Xenografts are composed of tissue taken from another species (i.e. from an animal source, usually bovine).

The term ‘composite graft’ refers to grafts that are composed of materials from different origins, usually autogenous bone mixed with other materials

CHARACTERISTICS OF THE IDEAL GRAFT MATERIAL

Nonimmunogenic The shape and size of material is stable over time. The material is reasonably malleable to carve or mold

into the desired shape. The material does not cause discoloration or

transillumination of the intervening tissue. The material is pliable. The material is easily obtainable. An adequate supply of the material is available. Minimum donor site morbidity

Aetiology of Saddle Nose

deformity which may necessiate

Bone grafting for augmentati

on

BONE GRAFTS USED FOR NASAL RECONSTRUCTION

NASAL BONE : Small pieces of nasal bone may be removed during the

course of traditional rhinoplasty and can be re implanted as a graft.

A particularly good use for this bone is as a graft to bone gaps at the lateral osteotomies.

HIP BONE GRAFTS : Less popular as bone tends to shrink (due to lack of

density of bone which inturn is helpful in carving it). Other problem being painful donor site.

CALVARIAL BONE GRAFTS : Very Dense Used most commonly for nasal reconstruction. The skull is formed from two layers of bone which are

separated by a type of marrow. The outer layer may be removed and used for grafting. It is possible to cause a fracture of the skull and there

is a remote chance of damage to the underlying brain. Not recommended after 50 yrs age as outer layer fuses

with inner due to disappearance of marrow.

RIB BONE : Commonly used. Hard outer cortical layer used for grafting.

Problems include : Ribs are curved. Painful donor site Scar on chest.

OLECRANON BONE GRAFT : The bone is not particularly dense but the small

quantity that would be harvested is likely to persist in the nose longer than a block of very porous (cancellous) bone from within the hip bone.

This scar and minor bone deformity at the elbow are very acceptable.

RADIAL BONE GRAFT :

BONE GRAFT FROM THE JAWS :

If small amount of bone required. Ramus Graft – from area of wisdom tooth. Tuberosity graft – from the posterior part of the upper

jaw behind the last molars. Chin Grafts Bone is harvested and placed immediately to the

required site where it is secured into place using small screws, which will be removed at a later date.

Can be done under LA or intravenous sedation.

TIBIAL BONE GRAFT Tibial bone graft is often used for sinus lift procedures

rather than nasal augmentation. One can expect some discomfort at the surgical site for

a period of days or sometimes a week or two, though walking is not restricted.

This surgery can be done as an outpatient at a surgical facility.

MASTOID BONE GRAFT Provides adequate autologous bone in most cases of

primary or revision rhinoplasty. The donor site carries low morbidity and a well

camouflaged scar. It is easily accessible.

SADDLE NOSE DEFORMITY RECONSTRUCTION WITH A SPLIT

CALVARIAL BONE L-SHAPED STRUT SURGICAL TECHNIQUE : HARVESTING AND FASHIONING OF GRAFT : Scalp incision is made along the superior rim of the temporalis

muscle in the nondominant temporoparietal region. A trifurcated incision is then created, extending the incision

inferiorly within the hairline to the preauricular sulcus. Dissection in the subgaleal plane is performed, and the

periosteum is incised 1.5 cm inferior to the scalp incision. The periosteum is then elevated off the calvarial bone in this

region. A 6-mm round cutting bur is used to circumferentially isolate a piece of outer table cortex.

Drilling is continued down to the level of the diploic bone. A curved sagittal saw and curved osteotome are used to lift the outer cortex free from the intact calvarium.

Bone wax is applied as necessary for hemostasis. The periosteum is then closed using polyglactin 910 (Vicryl) sutures, and the scalp is closed using subdermal 4-0 polyglactin 910 sutures and 4-0 chromic locking skin sutures.

A suction drain is placed in the subgaleal layer and is removed on postoperative day 1. The bone graft is divided into 2 pieces that are used to construct a dorsal onlay graft and columellar strut. The dimensions of each are based on the ideal nasal length and projection.5,6 The dorsal piece is contoured using 3- and 4-mm coarse and fine diamond burs to recreate the concavity of the natural dorsum.

The cortical side is placed superficially, and the cancellous side is placed deep.

The cephalic- most portion of the dorsal piece is thinned and beveled to enable a smooth transition with the patient’s intact bony nasal bridge. In addition, the dorsal piece is beveled laterally to prevent a noticeable ridge.

The 2 pieces are fastened together using a 1-mm titanium screw, in contrast to previously described tongue-in-groove techniques. The L-shaped strut is then ready for implantation

PLACEMENT OF THE L-SHAPED STRUT

The nasal skeleton is exposed using an external rhinoplasty approach through an inverted-V columellar incision with intravestibular marginal incisions.

Dissection is carried cephalically to the nasal dorsum. A small portion of the nasal root is filed down to enable smoother placement of the dorsal portion of the L-shaped strut.

This also creates a “raw” bony surface for direct bone-to bone contact, which hypothetically would enhance osseous integration and fusion of the bone graft.

The medial crura of the lower lateral cartilages are separated to enable placement of the caudal portion of the graft into a secure pocket. In a manner akin to the placement of a columellar strut, the bone graft is placed into a secure pocket between the medial crura.

The base of the L shaped strut rests on the pre maxilla and is secured with a transcrural suture. Once the L-shaped strut is positioned in place, the lower lateral cartilages are advanced over the caudal portion and vertex of the L-shaped strut using intradomal sutures.

Two wire-pass drill holes are made in the dorsal bone to place anchoring sutures to fix the lower lateral cartilages in position and maintain the midline position of the graft. The skin and soft-tissue nasal envelope is then closed.

CREATION OF OSTEOTOMIES  If osteotomies are necessary, a No. 11 blade is used to

create stab incisions in the cheek-nose junction bilaterally to access the lateral rim of the bony nasal pyramid.

Medial and lateral osteotomies are then created near the nasal bone midline and the nasofacial groove, respectively.

DRESSING  Contour taping is placed immediately after closure to shape

the external structure of the nose. A 1-piece standard porous cast (ThermaSplint; Whitehall Manufacturing, City of Industry, California) is placed superficial to the tape. The cast and tape are removed 1 week postoperatively.

RADIAL BONE GRAFT FOR SEPTAL CORRECTION

  Anaesthesia preferred – GA. After local anaesthetic infiltration the nasal structures were

exposed through an open rhinoplasty approach. Following hump resection, the septum was dissected

subperichondrially and resected leaving a 0.8 to 1-cm dorsal and caudal L-strut.

Deviated caudal segment of the septal cartilage was straightened medialized and secured to the periosteum of the anterior nasal spine.

Radial bone graft was accessed from the lateral antecubital region, and bone graft was harvested from the lateral side of radial bone.

Radial bone is triangular in cross section. The anterior and posterior surfaces of the radius are generally smooth, whereas an oval roughening for the attachment of pronator teres marks approximatelly the middle of the lateral surface of the radius.

Bone graft was harvested a segment (about 5×1 cm) located between the insertion of the pronator teres and the brachioradialis muscles.

Lateral antecubital nerve, flexor and extensor muscles were protected during bone graft harvesting procedure.

Bone graft was thinned by bone filing and shaped in the form of a L-strut as "key in the keyhole pattern”.

The dorsal strut was placed by tongue in groove technique on the anterior nasal spine. L-strut frame was sutured under the upper lateral cartilage remnants and between the domes of two lower lateral cartilages to hide palpable edges and secure it in place.

Lateral and median osteotomies were also performed if bony pyramid was also deviated.

Any residual irregularities on the dorsum were camouflaged with Erol's Turkish delight. 

Tipplasty was performed if necessary. Following closure, nasal packing and plaster cast were applied. A plaster cast was also applied on the forearm and removed 1 week later.

The packing and the nasal splint were removed at 4th and 7th days, respectively.

OLECRANON BONE GRAFTSURGICAL PROCEDURE FOR GRAFT REMOVAL The non-dominant forearm was chosen for removal of the

olecranon bone graft. The proximal third of the posterior face was infiltrated followed

by a longitudinal incision and dissection of the planes. The cortex of the olecranon was measured according to the nasal

defect for repair and the graft was removed with a bone saw or a simple chisel.

Upon removal, the olecranon was placed in a container with saline solution and the donor area was covered with bone wax.

Synthesis was carried out by planes, with absorbable sutures and of skin with 4.0 nylon intradermal threads.

Finally, the limb was covered with a crepe bandage. A tourniquet was not necessary. The graft was transferred into the recipient area with external anchoring with micropore tape for 21 days; rigid fixation was not used.

Possible graft resorption was monitored by anthropometric measurements of the nose with photographic documentation and graft radiological control.

Patients reported temporary paresthesia in the forearm scar (donor area), with a complete recovery within 1 year.

The olecranon bone graft proved to be a good option for primary or secondary rhinoplasty for the treatment of “saddle-back” nose. Long-term resorption or morbidity of the donor area has not been observed so far. This procedure ensures satisfactory, predictable, and long-lasting aesthetic results

AUGMENTATION OF NASAL TIP PROJECTION USING THE INFERIOR TURBINATE

GRAFT HARVEST AND PREPARATION Inferior partial turbinectomy is performed in standard fashion,

following decongestion. After careful infracture with a freer elevator, a right-angled scissor

is used to resect the anterior head or two-thirds of the turbinate, including bone and soft tissue. After careful extraction from the nose, the soft tissue covering the turbinate bone is removed using iris scissors or a No. 15 blade, taking care to avoid trauma to the turbinate bone.

The size of the implant will vary depending on the patient's degree of bony inferior turbinate hypertrophy. The graft is then shaped using a Mayo scissor. Hemostasis of the cut end of the turbinate is achieved using suction electrocautery.

PLACEMENT Placement of the graft can be done either Endonasally or using

an open approach. If an endonasal approach is used, it is important for the surgeon

to carry the marginal incision almost to the medial crural footplate and then to dissect the lower lateral cartilage free along its length.

This allows direct placement of the strut, which will not bend significantly, and minimizes the risk of fracturing the implant. The marginal and transfixion sutures are closed with 4-0 chromic gut.

The nose is then taped and cast in standard fashion. A stabilizing suture can be placed in a septal-columellar fashion. Because driving a needle through the implant risks fracture, place the suture just posterior to the implant in the membranous septum.

Recent AdvanceMASTOID BONE A NEW GRAFT MATERIAL IN

RHINOPLASTY

The mastoid bone graft provides adequate autologous bone in most cases of primary or revision rhinoplasty.

The donor site carries low morbidity and a well camouflaged scar.

It is easily accessible especially for the otolaryngologist who is accustomed to operating on the mastoid bone

Referemces :Scott Brown 7th Edition

Barone CM, Jimenez DF and Goodrich JT (2008).

Exorbitism. In: Goodrich JT (ed.), Neurosurgical

Operative Atlas. Paediatric Neurosurgery, 2nd edn. New York: Thieme, pp. 76-82.

Chait LA, Becker H and Cort A (1980). The versatile costal osteochondral graft in nasal reconstruction.

Br J Plast Surg, 33(2): 179-184.

David DJ and Moore MH (1989). Cantilever nasal bone grafting with miniscrew fixation. Plast Reconstr Surg, 83(4): 728-732.

Farina R and Villano JB (1971). Follow-up of bone grafts to the nose. Plast Reconstr Surg, 48(3):251-255.

Gewalli F, Berlanga F, Ortiz-Monasterio F and Holmström H (2008). Nasomaxillary reconstruction in Binder Syndrome: bone versus cartilage grafts. A long-term intercenter comparison between Sweden and Mexico. J Craniofac Surg, 19(5): 1225-1236.

External Rhinoplasty The elephant trunk incision, the trans columellar incision,

The decortication technique, the external approach and open or external rhinoplasty.

INDICATIONS Congenital deformities, such as the cleft lip nose Extensive revision surgery Severe nasal trauma Elaborate reduction and augmentation procedures Marked tip deformities The need for extra tip rotation The correction of extreme overprojection Situations where assessment of the exact pathology is

difficult.

PRINCIPLES OF EXTERNAL RHINOPLASTY

Conservation of the structural support of the nose by exposing the pathology and allowing open access for corrective surgical manoeuvres. Correct incision placement and meticulous wound closure are essential. Lower and upper lateral cartilages together with the bony dorsum can be exposed to the nasofrontal angle in their undisturbed positions.By dividing the upper laterals from the quadrilateral cartilage, the whole of the septum is accessible from the cephalic as well as the caudal aspect.

Other benefits include Binocular vision Use of both hands Control of bleeding with diathermy Precise placement and suturing of struts, Battens and shield grafts A very useful teaching tool. It is important to appreciate that whilst the major tip support mechanisms are respected in the external approach, the disruption of the skin soft tissue envelope from the lower lateral cartilages and the division of the medial intercrural ligamentous fibrous tissue leads to loss of some of the minor tip support mechanisms, and therefore some tip ptosis should be anticipated in all cases.

SURGICAL TECHNIQUE

Incisions

The broken trans columellar incision is most commonly used and variations include the step, gullwing and inverted 'V' configurations.The mid-columella incision should be situated above the level of the medial crural footplates to ensure adequate support, thus preventing a depressed scar The vertical columellar parts of the marginal incisions are then placed 1.5-2 mm inside the vestibule and joined by careful undermining with scissors of the columella skin.

SURGICAL TECHNIQUE

Dissection of the soft tissue envelope

This starts in the subperichondrial plane in the domal area. It can be helpful to vertically incise the perichondrium at the caudal end of the cartilaginous vault in the midline, after which subperichondrial dissection can proceed from medial to lateral and in a cephalic direction. Dissection of the soft tissue of the bony pyramid in a subperiosteal plane should start 2-3 mm parallel to and above the caudal end of both nasal bones. In the case of grafting procedures for augmentation, care should be taken that the overlying soft tissue has sufficient viability.

SURGICAL TECHNIQUE

Blanching of the skin over an augmentation graft is a warning sign which should not be neglected. A slight reduction of the graft size will prevent possible skin necrosis.

A Meticulous closure of incision is done following completion of surgery.