Osteoarthritis of hip in orthoapedics.pptx

Osteoarthritis of hip in orthopedics for undergraduate and post graduate teaching

1. Osteoarthritis of hip

2. Osteoarthritis of unknown cause that affects one or more joints usually is designated primary (idiopathic) osteoarthritis osteoarthritis in which a preexisting cause such as coxa plana or congenital subluxation of the hip is evident is called secondary osteoarthritis . In the hip, osteoarthritis is most often secondary, brought on by an anatomical deformity that causes loading on an area of the joint in excess of that tolerated by normal articular cartilage and subchondral bone. osteoarthritis of the hip may be prevented if the predisposing deformity can be corrected before the onset of degenerative changes

3. end stage of these two types of osteoarthritis may be the same , the rate of degeneration slower and less predictable in primary arthritis, which may remain stationary for a considerable period and may improve without treatment . Treatment of primary osteoarthritis usually is nonsurgical as long as possible . secondary osteoarthritis, when pain and destruction begin , progression usually is relentless , and nonsurgical methods usually are futile

4. Operations for osteoarthritis can be divided into two groups : (1) operations that preserve the patient's own hip joint a. excision of osteophytes and curettage and packing of acetabular cysts b. proximal femoral or periacetabular osteotomy , and c. hanging hip operation (muscle release ) (2) operations that reconstruct the hip joint (a) arthrodesis (b) prosthetic femoral head replacement ( hemiarthroplasty ), ( c) resurfacing arthroplasty , and ( d) total hip arthroplasty .

5. Before the onset of osteoarthritis , if normal or near-normal function of the hip can be maintained, reconstructive osteotomy can prevent or delay the development of osteoarthritis . If mild or moderate osteoarthritis is present, a salvage osteotomy can improve function and may delay the need for total hip arthroplasty .

6. Therapeutic Intervention in Hip Disease. Factors Reconstructive Osteotomy Salvage Osteotomy Age Generally <25 years Generally <50 years (some biological plasticity remains) Symptoms Minimal (but progressive) Moderate to severe Motion Near-normal >60 degrees flexion Function Near-normal Fair to poor Pathoanatomy No irreversible changes Irreversible changes Radiography Congruent but malaligned surfaces Cartilage narrowing or incongruity or both Prognosis if untreated Poor Poor

7. Goals of treatment goal- reconstructive osteotomies , femoral or pelvic, is to a.restore as nearly normal anatomy as possible , b.returning joint pressures and loading patterns to normal . Reconstructive osteotomies generally are indicated in younger patients (<30 years old) if the shape of the articular surfaces is relatively normal, and the primary problem is malalignment . 2 . goals-salvage osteotomies are to relieve pain and improve function enough to delay the need for total hip arthroplasty , especially in active patients <50yrs.

8. Evaluation Radiographic evaluation a standing anteroposterior view and a “false profile” view. This latter view is a true lateral view made with the patient standing, the pelvis turned 25 degrees toward the beam, and the ipsilateral foot and knee and the radiographic film perpendicular to the beam

9. Pauwels - radiographs of the hip be made with the joint a. in maximal adduction and b. maximal abduction. studied carefully to determine in which of the two positions the femoral head fits better in the acetabulum . If it fits better with the hip in abduction , an adduction ( varus ) osteotomy , in which a wedge of bone with its base medial is removed from the trochanteric area if the head fits better in the acetabulum with the hip in adduction , an abduction ( valgus ) osteotomy , in which a wedge of bone with its base lateral is removed, is appropriate . - Three-dimensional CT

10. Varus osteostomy Designed to elevate the greater trochanter and move it laterally while moving the abductor and psoas muscles medially, to restore joint congruity and decrease muscle forces around the hip INDICATIONS 1.for patients with a spherical femoral head 2. little or no acetabular dysplasia (a center-edge angle of at least 15 to 20 degrees), 3.signs of lateral overloading 4.a valgus neck-shaft angle of more than 135 degrees. Varus osteotomy with medial displacement of the femoral shaft relaxes the abductor, psoas , and adductor muscles; unloads the hip joint; and increases the weight bearing surface. Most authors recommend medial displacement of 10 to 15 mm to keep the ipsilateral knee centered under the femoral head and to maintain the mechanical axis of the leg. DISADVANTAGES A.shortens the limb to some degree, creates a Trendelenburg gait that may persist for months after surgery. B.increases the prominence of the greater trochanter . Limb shortening can be minimized by making a smaller medial osteotomy and transposing it to the lateral side .

11. Varus osteotomy increases weight bearing area of femoral head while relaxing all three important muscle groups around hip joint

12. Three types of wedges cut for varus osteotomy . A, Original technique of Pauwels with proximal osteotomy made transversely at distal end of greater trochanter . This type of osteotomy makes it more difficult to correct rotation and to use right-angled blade plate . B , Original Müller technique of excision of wide wedge based medially with distal osteotomy cut transversely across shaft at just above level of lesser trochanter . C , Later technique of Müller using small half wedge cut medially and transposed laterally

13. VALGUS OSTEOTOMY transfer the center of hip rotation medially from the superior aspect of the acetabulum to increase joint congruity and the weight bearing area of the femoral head . Osteotomy of the greater trochanter often is performed with valgus femoral osteotomy to move the greater trochanter laterally . INDICATIONS patients younger than 40 years old with unilateral involvement good preoperative range of motion, and a mechanical (secondary) cause. CONTRAINDICATION preoperative flexion of less than 60 degrees as a relative contraindication to valgus osteotomy

14. Valgus osteotomy increases weight bearing area of femoral head but does not produce muscle relaxation . Muscle relaxation can be obtained by tenotomy of iliopsoas and adductor muscles.

15. Osteotomy - PAIN RELIEF in an obvious increase in the width of the joint space and in disappearance of cystic and sclerotic areas from the femoral head and acetabulum .

16. FIXATION all osteotomies be fixed with rigid internal fixation, ADVANTAGES (1) The fragments are maintained in proper position (2) the danger of limitation of motion of the hip and knee is greatly decreased (3) the patient can be allowed out of bed early; and ( 4) pulmonary, urological, and other medical complications are decreased . A device frequently used for rigid internal fixation of intertrochanteric osteotomies is the ASIF, or right-angled, blade plate

17. PROBLEMS ENCOUNTERED Nonunion an incidence of 20% . CAUSES 1.displacing the distal fragment too far medially is the most common cause of nonunion; the incidence increased sharply when displacement approached or exceeded 60% of the diameter of the shaft . 2. Fixing the osteotomy in too much of a varus position also is considered a cause. Limiting displacement to 50%, producing an angle between the neck and shaft of at least 140 degrees (unless the osteotomy is a varus one), and using the compression device of Müller are advised.