الفهرس 
Applied Surgical Anatomy of The AcetabulumOnly 14 pages are availabe for public view
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Abstract
Bone deficiency in the acetabulum can be encountered in primary and revision acetabular reconstruction. Primary deficiencies result from either an abnormality of growth or a condition that alters the shape of the acetabulum.(104)
Bone deficiencies encountered during revision arthroplasty continue to be the most common. Many classification schemes have been formulated to describe acetabular deficiencies. The most commonly used schemes are those that are easy to remember, easy to reproduce, and are most useful in guiding treatment options.
The deficient acetabulum requires reconstruction so that the acetabular component has adequate bony coverage and support. This is to restore anatomy and leg length and restore bone stock for future revisions.
Management of acetabular deficiency in total hip arthroplasty can be extremely challenging. A successful outcome requires good orientation about applied surgical anatomy of the acetabulum, careful preoperative planning, identification of complex defects, and stable reconstruction. Acetabular deficiencies are classified according to clinical radiographs, anticipated bone loss during removal of implants, and intraoperative assessment of host bone stock.(104)
Various techniques have been reported for reconstructing the deficient acetabulum at the time of total hip arthroplasty. The two most common techniques are reconstructing the acetabulum at the correct anatomical level in combination with grafting, and proximal placement of the cup (also called the high hip center) .(105)
Acetabular reconstruction is more reasonable as it allows early painless movement of the patient. It also restores the bone stock for future revisions if needed, corrects present deformity and restores limb length. On the other hands the high hip center technique is accompanied with limb length discrepancy, weak abductor muscles, increased incidence of dislocation, and a difficult revision surgery if needed.(105)
Management principles include the use of structural grafts in case of segmental defects, morcellized graft in case of cavitary defects, and combining structural and morcellized graft in case of combined cavitary and segmental defects in addition to ring reconstruction when needed.(106)
Despite the realtively short follow-up period about Porous tantalum, these modular components appear to provide apromising choice, with added advantage that they accept a variety of polyethylene liners. Porous tantalum showed excellent bone ingrowth and no change in position was noted.the healing and incorporation of allograft bone nearby the porous tantalum is remarkable.clinical results were good and radiological assessment showed excellent gap filling, bone apposition and incorporation of bone grafts.similar results have been reported in other studies using TM cups.(107)