D ISTRACTION O STEOGENESIS Shelby Marks, Kijeon Choi, Taylor - PowerPoint PPT Presentation

D ISTRACTION O STEOGENESIS Shelby Marks, Kijeon Choi, Taylor Tebano, Stanley Gelin, and Sarah Bradner

L EARNING O BJECTIVES  To understand the advancement of bone elongation techniques that lead to modern day practice.  Be able to describe what distraction osteogenesis is and how it works.  Identify and compare the different distraction osteogenetic surgical processes to achieve skeletal reconstruction.  Understand the many causes/diseases for which distraction osteogenesis is used.  Recognize the complications and risks associated with the process and identify post-operative care.

D ISTRACTION O STEOGENESIS  Surgical reconstruction of skeletal deformities and lengthening of the long bones of the body  Procedure that moves 2 bone segments apart using an external saw and allows new bone in gap  Many FDA approved distraction devices

H ISTORY ‣ Skeletal traction was described as long ago as by Hippocrates (460-377 B.C.) when traction on long bones was performed by means of rubber straps ‣ Alessandro Codivilla (1861 -1912), Pioneer of bone elongation techniques ‣ Italian Surgeon ‣ Published 1905 case report of femoral extension using axial forces ‣ Introduced Limb lengthening techniques that had a high complication rate ‣ Popularized by Russian orthopedic surgeon Gavril Ilizarov

G AVRIL I LIZAROV – Gavriil Abramovich Ilizarov was born in Caucasus (former USSR) in 1921 – No formal schooling till age 11 – Lone physician in Kurgan, Serbia – Developed Ilizarov method – An external fixator to regenerate bone under tension – modular ring – Died July 24 1992 in Kurgan, Russia due to heart failure

R USSIAN ILIZAROV S CIENTIFIC C ENTER FOR R ESTORATIVE T RAUMATOLOGY AND O RTHOPAEDICS • Founded in 1971 in Kurgan, Serbia • Home to Ilizarov method • The first department in Russia for managing bone infection • Place where limb lengthening techniques were first devised and introduced into clinical practice.

H OW DOES IT WORK ?  Must be gradual too quick : fibrous union instead of osseointegration too slow: early bone union Steps: Surgeon makes ostectomy (break) in abnormal bone 1) and places distraction device. Allowed to start a few days of healing. Parent/ guardian turns a screw on distractor after 2) surgery at home to stretch healing tissue (stretch~1mm/day) Stretch regenerated tissue forms into new bone 3) over next 2 months After bone is formed at necessary length, device is 4) removed through a 2 nd surgery

C ELLULAR LEVEL :  Aka callus distraction  Inflammation: formation of blood clot and ingrowth of angiogenic elements  Soft callus: replacement of blood clot with granulation tissue and fibrocartilage  Hard Callus: granulation and fibrocartilage is is replaced with woven bone  Remodeling: woven bone is replaced with lamellar bone

T ECHNIQUES RIGID external device (RED) Frames surgery Intramedullary Nail -Albizzia -Guichet -FITbone -ISKD LRS

I. R IGID E XTERNAL D EVICE (RED)  Found to give reliable results, control bone movements  easy removal  Cranial halo (semicircular piece) encircles front of patients forehead and secured with pins. Pins touch but do not penetrate bone.  Cranial halo is attached to vertical graphite

E XTERNAL D EVICE Ex: Midface advancement - metal “halo” device and dental splint remain after operation during healing (10weeks) - 2 nd surgery removes halo & splint - caregiver turns twice a day - 1/8 th inch scar on lower eyelid but heals well

M IDFACE A DVANCEMENT  Make cut in bones of face at specific points  Loosen midface from rest of skull  Advance into correct position New advantages: -bone grafts from rib and skull are no longer needed with plates and screws -larger advances in midface are achievable -skin and muscles are now stretched too and do not fight to push back -duration of procedure is shorter

II. F RAMES S URGERY “I LIZAROV S URGERY ”  Oldest and most common method  Application of circular frame or external fixator  Most common 1) Ilizarov frame 2) Taylor Spatial frame

F RAME MAKE - UP  Frames are circular external fixators that surround limb  Consists of 4-6 rings made of stainless steel or carbon fiber  Thin wires and half pins are fixed to rings and pass through skin to bone Half pins: attached on one side of frame Wires: other side through bone and attached and held under tension Rods and struts: between rings for stability and adjustment

I NTRAMEDULLARY NAIL

A LBIZZIA - D R . G UICHET 1987  Internal telescopic nail with lengthening mechanism  Lengthening achieved by rotation  Rotation makes “click” noise  Click allows higher accuracy, patient knows how much they lengthened it  15 clicks~1 mm  Fully implantable nail allows for full weight bearing  4 inch gain  Small scar

G UICHET - ADVANCED A LBIZZIA (2009)  Improved method  Stronger steel makes it weight bearing  No longer “one size fits all”  Can accommodate different sized limbs

FIT BONE (F ULLY INTEGRATED TELESCOPIC BONE )  Nail is distraction device powered by internal engine  Engine activated by hand remote  Activates distraction by sending messages to receiver below skin

H OW DOES IT WORK ?  Similar function as car antenna  Fitbone elongation is propelled by gear  Inserted through “model entrance point”  Tiny scar

III. ISKD ( INTRAMEDULLARY S KELETAL K INETIC D ISTRACTOR )  Activated by polar movements through small rotation of bone segment being lengthened  Amount of length is determined pre-op and set at time of insertion  Allows 3’’ gain

IV. LRS ( LIMB RECONSTRUCTION SYSTEM )  Includes different clamps that slide on rigid rail and connected with distraction units  Relies on callus distraction  Stability by allowing different bone screw position in clamp along length of bone  Rail length pick depending on size of limb  Osteotite bone screws with hydroxyapetite coating

Distraction Osteogenesis for Congenital Deformities Types of Congenital Deformities:  limb lengthening  facial deformities  amputation at the elbow  correction of airway obstruction in micrognathia  Fibular hemimelia  Hemihypertrophy  Ollier � s disease

L IMB L ENGTHENING  Procedure:  a bone segment is surgically cute and a distraction device is used to slowly pull the two ends apart.  After the desired lengthening has been achieved, the bone consolidates until the lengthened gap has completely calcified.  Distraction phase and Consolidation Phase in distraction osteogenesis.  History: Discovered by Russian Orthopedic Gavril Ilizarov  Technique: external fixator  Today: minimally invasive techniques performed with internal distraction device

A MPUTATION AT THE ELBOW • Patients with short congenital amputations below the elbow often function as if they have had a disarticulation of the elbow • Patients had lengthening of stumps by the Ilizarov technique to improve fitting of prostheses

C ONGENITAL F ACIAL D EFORMITIES  Hemifacial Microsomia: a rare congenital disease characterized by facial asymmetry  Cleft palate: separation of the roof of the mouth that occurs in early development of fetus  Severe mandibular hypoplasia (small lower jaw): causes breathing problems includes conditions as:  Brachygnathia : abnormal shortness or recession of the lower jaw  Micrognathia : an abnormally small, lower jaw and chin.  Why?

Hemifacial Microsomia Distraction Process  Bimaxillary distraction osteogenesis allows correction of mandibular  asymmetry with simultaneous correction of the position of the maxilla Cleft Palate

C ORRECTION OF AIRWAY OBSTRUCTION  Micrognathia  Can use tracheostomy: May be life saving but is associated with complications and developmental problems  Alternative: internal mandibular distraction osteogenesis

F ACIAL D EFORMITIES  Treacher-Collins syndrome: a condition that affects the development of bones and other tissues in the face  Pierre-Robin Sequence: a group of disorders occurring together that includes a small, lower jaw, breathing problems, and a tongue that tends to ball up at the back of the mouth  Facial Injuries:  cause damage to the maxilla or mandible  most common condition for which distraction osteogenesis is performed

M AXILLOFACIAL D ISTRACTION O STEOGENESIS  Two Main Uses: 1. Congenital Craniofacial Defects 2. Facial injuries from trauma/ impact  Requires making bones longer

M AXILLOFACIAL DO P ROCESS  Bonus Question :  Why is it the hardest to grow bone in the face considering the current methods?

M AXILLOFACIAL DO  Bone movements must be carefully planned before a device is implanted  There are no devices that can change trajectory mid-course

M AXILLOFACIAL DO P ROCEDURES  Current Methods:  Future device goals  External and linear  Curvilinear devices (one dimension) (capable of moving bone in 3 dimensions)  Move bone continuously, not in increments of 1mm  Causes less pain, wouldn’t require patient compliance, might promote faster bone growth

D EVELOPMENTAL D EFORMITIES  Clavicle Lengthening  Reconstruction of forearm deformity  Foot deformities  Bow legs