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Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)
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Orthopedics 5th year, 5th lecture (Dr. Omar Barawi)

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The lecture has been given on Oct. 30th, 2010 by Dr. Omar Barawi.

The lecture has been given on Oct. 30th, 2010 by Dr. Omar Barawi.

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  • 1. BONE-GRAFTS   Bone-grafts are both osteoinductive and osteoconductive,  i.e. they are able to stimulate osteogenesis, and they also  provide linkage across defects and a scaffold upon which new  bone can form. Osteogenesis is brought about partly by the  activity of cells surviving on the surface of the graft, but mainly  by the stimulation of osteoprogenitor cells in the host bed - an  effect that is due to the presence of bone morphogenetic  protein in the graft matrix. Cancellous grafts are more rapidly  incorporated into host bone than cortical grafts, but  sometimes the greater strength of cortical bone is needed to  provide structural integrity. 
  • 2.  TYPES:  1- Autografts (autogenous grafts)  In these, bone is transferred from one place to another in the same  individual. This is the most commonly used form of bone-grafting, but it  depends on there being sufficient donor bone of the sort required and a  recipient site with a clean vascular bed. Most of the transplanted bone  dies, but it continues to act as a scaffold, which is gradually replaced by a  process of creeping substitution.  Cancellous Autografts can be obtained  from the thicker portions of the ilium, the greater trochanter, the  proximal metaphysis of the tibia, the lower radius, the olecranon, or from  an excised femoral head. Cortical grafts can harvested from any  convenient long bone or from the iliac crest; they usually need to be fixed  with screws, sometimes reinforced by a plate, and can be placed on the  host bone, or inlaid, or slid along the long axis of the bone.       The ideal vascularised autograft is one with an intact blood supply.  Bone is transferred complete with its blood vessels, which are  anastomosed to vessels at the recipient site. The technique is difficult and  time consuming, requiring microsurgical skill. Available donor sites  include the iliac crest (complete with one of the circumflex arteries), the  fibula (with the peroneal artery) and the radial shaft. Vascularized grafts  remain completely viable and become incorporated by a process  analogous to fracture healing. 
  • 3. 2- Allografts (homografts) With these, bone is transferred from one individual (alive  or dead) to another of the same species. The bone is  harvested and stored until needed. The method is  particularly useful when large defects have to be filled.    Fresh allografts, though dead, are not immunologically  inert. They induce an inflammatory response in the host  and this may lead to rejection. However, the antigenicity  can be reduced by freezing or freeze-drying, or by ionizing  radiation. The process of incorporation (when it occurs) is  similar to that with auto grafts but slower and less  -complete. Demineralization is another way of reducing  antigenicity and it may also enhance the osteoinductive  properties of the graft. 
  • 4. Allografts are plentiful and can be stored for long periods.  However, sterility must be ensured. This can be done by  exposure to ethylene oxide or by ionizing radiation, but  their physical properties and potential for osteoinduction  may be altered by doses that are high graft must then be  harvested under sterile conditions and the donor must be  cleared for  (A)malignancy, (B)venereal disease,  (C)hepatitis and (D)human immunodeficiency virus  (HIV). 
  • 5. Other types of graft 3- Xenografts are obtained from another mammalian species, such as  pigs or cows. After treatment for antigenicity, they should,  theoretically, behave like allografts, but in practice they  are much less effective unless host marrow is added to the  graft.  4-  'Artificial bone‘  made of hydroxyapatite composites can be used in the  same way to fill a cavity or bridge a small gap. Bioactive  bone cements (injectable calcium phosphate preparations)  offer a simple alternative, e.g. for replacing bone loss in  metaphyseal fractures. 
  • 6. Applications  Cancellous grafts are used for filling cavities,  augmenting healing and promoting arthrodesis.  Cortical or corticocancellous grafts are needed where  bone has been lost as a result of trauma or has been  removed because it contained a tumour. When  reinforced by metallic implants, large gaps can be  filled.         Vascularized grafts tend to be used only in  exceptional circumstances, such as treating large  bone defects. 
  • 7. DISTRACTION HISTOGENESIS AND LIMB RECONSTRUCTION   Present-day limb reconstruction is founded on the  principle that new-bone formation is stimulated in  response to gradual increases in tension. This was  originally discovered by Gavril Ilizarov in Russia and the  application of this principle to bone reconstruction is  widely referred to as the Ilizarov method. 
  • 8. Distraction histogenesis  Callotasis   Callus distraction, or callotasis, is perhaps the single most  important application of the tension-stress principle. It is used  for limb lengthening or the filling of large defects in bone,  through either bone transport or other strategies. The basis of  the technique is to produce a careful fracture through the bone,  followed by a short wait (5-10 days) before the young callus is  gradually distracted by traction on the bone via a circular or  unilateral external fixator" Distraction proceeds at 1 mm a day,  with small (usually 0.25 mm) increments spaced out evenly. New  callus can be seen on the x-ray after 3 weeks; in optimum  conditions, it forms an even column in the gap between the bone  fragments (this is called the regenerate) . If the distraction rate is  too fast, or the osteotomy performed poorly, the regenerate may  be thin with an hourglass appearance; conversely,
  • 9. if distraction is too slow, it may appear bulbous or, worse  still, may consolidate prematurely, thereby preventing any  further lengthening. When the desired length is reached, a  second waiting period follows which allows the regenerate  callus to consolidate and harden. Weight-bearing is  permitted throughout this period. When cortices of even  thickness appear in the regenerate, the fixator can be  removed. Throughout treatment, physiotherapy is  important to preserve joint movement and avoid  contractures. Patients should be warned that bone  lengthening takes months rather than weeks and carries a  risk of complications, such as pin-track infection,  angulatory deformity, re-fracture and non-union. Ilizarov  techniques should be employed only by surgeons who  have undergone training in this method. 
  • 10. Chondrodiatasis   In children, bone lengthening can be achieved by  distracting the physis (growth plate). No osteotomy is  needed and the distraction rate is slower, usually 0.25 mm  twice daily. Although a wide, even column of regenerate is  usually seen, the fate of the physis is sealed: it frequently  closes after the process, and for this reason the technique  is best reserved for children close to the end of growth. 
  • 11. Bone transport   The principle of callotasis is used not only for limb  lengthening bur also as a means of treating non-union  and filling defects in bone. Bone transport allows a  defect (or gap) to be filled in gradually creating a  'floating' segment of bone through corticotomy either  proximal or distal to the defect, and slowly moving  the isolated segment of bone across the gap. As the  segment is transported from the corticotomy site to  the new docking site, leaves a trail of regenerate new  bone behind it. An external fixator provides stability  during this process. 
  • 12. DEFORMITIES OF THE FOOT   The normal position of the foot is plantigrade - i.e.  when the patient stands, the sole is at right angles to  the leg. Equinus (like a horse's foot) means .that the  hindfoot is fixed in plantarflexion (pointing  downwards), Plantaris looks similar, but the ankle is  neutral and only the forefoot is plantarflexed.  Calcaneus is fixed dorsiflexion at the ankle. A  dorsiflexion deformity in the mid-foot produces a  rocker-bottom foot.     
  • 13. Normally the medial border of the foot, even when weight-bearing, forms a longitudinal arch. The arrangement of the metatarsals also produces an anterior or transverse arch in the forefoot. Flattening of the longitudinal arch is referred to as a planus deformity or flat-foot; and a dropped metatarsal arch as anterior flat-foot. An excessively high arch produces a cavus deformity.  Common deformities of the toes are lateral deviation of the big toe (hallux valgus), proximal interphalangeal flexion of one of the lesser toes (hammer-toe) and flexion of both interphalangeal joints of several toes (claw-toes).
  • 14. CONGENITAL TALIPES EQUINOVARUS (IDIOPATHIC CLUB-FOOT)  In this deformity the heel is in equinus (pointing downwards), the entire hindfoot in varus (tilted towards the midline) and the mid-foot and forefoot adducted and supinated (twisted medially and the sole turned upwards). It is relatively common; the incidence is 1 or 2 per 1000 birth and boys are affected twice as often as girls. The condition is bilateral in one-third of cases. Similar deformities are seen in neurological disorders e.g., myelomeningocele, and in arthrogryposis.  The skin and soft tissues of the calf and the medial side of the foot are short and underdeveloped. If the condition is not corrected early, secondary growth changes occur in the bones and these are permanent. Even with treatment, the foot is liable to be short and the calf may remain thin.
  • 15. Clinical features  The deformity is usually obvious at birth; the foot is both turned and twisted inwards so that the sole faces posteromedially. The heel is usually small and high, and deep creases appear posteriorly and medially. In a normal baby the foot can be dorsiflexed and everted until the toes almost touch the front of the leg. In club-foot this manoeuvre meets with varying degrees of resistance and in severe cases the deformity is fixed.  The infant must always be examined for associated disorders such as congenital hip dislocation and spina bifida.  X-rays The tarsal bones are incompletely ossified at this age and the anatomy is therefore difficult to define. However, the shape and position of the tarsal ossific centres are helpful in assessing progress after treatment.
  • 16. Treatment   The aim of treatment is to produce and maintain a  plantigrade, supple foot that will function well. There are  several methods of treatment, but relapse is common,  especially in babies with associated neuromuscular  disorders.    Conservative treatment  Treatment should begin early, preferably within a day or two  of birth. This consists of repeated manipulation and adhesive  strapping or application of plaster-of-Paris casts, which will  maintain the correction. If adhesive strapping is used,  parent, are taught how to do the manipulation and they can  then carry out gentle stretches on a regular basis with the  strapping still in place. Treatment is supervised by a  physiotherapist, who alters the strapping as correction is  gradually obtained. Plaster-of-Paris casting requires serial  changes and manipulations in a clinic setting. Sometimes  surgical release of the Achilles tendon is needed to complete  the correction. 
  • 17. Operative treatment Resistant cases will need surgery. The objectives are  (a) the complete release of joint tethers (capsular  and ligamentous contractures and fibrotic bands)  and (b) lengthening of tendons so that the foot can  be positioned normally without undue tension. A  detailed knowledge of the pathological anatomy is a  sine qua non. After operative correction, the foot is  immobilized in its corrected position in a plaster  cast. Kirschner wires are sometimes inserted across  the intertarsal and ankle joints to augment the hold.  The wires and cast are removed at 6-8 weeks, after  which hobble boots (Dennis Browne) or a  customized orthosis are used to maintain the 
  • 18. LATE OR RELAPSED CLUB-FOOT   Late presenters often have severe deformities with  secondary bony changes, and the relapsed club-foot  is complicated by scarring from previous surgery. A  revision .of the soft-tissue releases may be  considered; this can be combined with shortening  of the lateral side of the foot by calcaneocuboid  fusion or cuboid enucleation (Dilwyn Evans).  Alternatively, gradual correction by means of a  circular external fixator (the Ilizarov method) has  proved effective in treating difficult relapsed cases  and severe deformities; the early results are  encouraging.  

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