Pericapsular Osteotomies of Pemberton and Dega

 

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DEFINITION

The Pemberton7 ( FIG 1) and Dega1, 2 ( FIG 2) osteotomies are performed for acetabular dysplasia that is either part of a developmental disorder or an acquired disorder due to muscle imbalance in neuromuscular conditions.

These are not reorienting procedures such as an innominate osteotomy but rather reshaping procedures that alter the geometry of the acetabulum and its volume.6, 11

They are used to increase anterior and lateral acetabular coverage.

 

 

ANATOMY

 

The acetabulum develops at the confluence of the growth centers of the ilium, ischium, and pubis.

 

Normal growth of the acetabulum requires not only that all of these growth centers remain open and function normally but also that the femoral head remains concentrically reduced and stable within the acetabulum.

 

If the growth centers are damaged, either from pathologic conditions or iatrogenically, or if the femoral head is not stable within the acetabulum, normal growth is unlikely to occur and hip dysplasia develops.

 

 

 

FIG 1 • Pemberton osteotomy depicted on a bone model viewed from anteriorly (A), from inside the pelvis medially (B), and from outside the pelvis laterally (C). The osteotomy starts at the AIIS and extends posteriorly following the insertion of the capsule. It then turns caudally and bisects the posterior column to the level of the triradiate cartilage. D. AP radiograph of a Pemberton osteotomy in a 2-year-old child.

 

PATHOGENESIS

 

Because of an abnormality in the growth centers of the acetabulum, abnormal periosteal growth, or abnormal positioning of the femoral head, the acetabulum does not develop properly.

 

Even with a concentric reduction of the femoral head, the prior period of abnormal growth may prevent the acetabulum from achieving a normal configuration at maturity. The older the child is at the time of reduction, the more likely an osteotomy will be necessary to normalize acetabular appearance.

 

NATURAL HISTORY

 

Many patients with acetabular dysplasia develop subluxation or dislocation of the femoral head. This can lead to early arthritis as an adult.

 

The degree of subluxation does not necessarily correlate with the time to onset of symptoms or the degree of arthritic changes.

 

PATIENT HISTORY AND PHYSICAL FINDINGS

 

Developmental hip dysplasia is a spectrum of pathology that can be diagnosed by physical examination in newborns and young infants if instability of the hip exists but may require ultrasonography or radiographs for diagnosis in cases of dysplasia without clinical instability.

 

 

P.895

 

 

 

 

FIG 2 • Dega osteotomy depicted on bone model viewed from anteriorly (A), from inside the pelvis medially (B), and from outside the pelvis laterally (C). As for the Pemberton, the Dega osteotomy starts at the AIIS and

extends posteriorly following the insertion of the capsule. However, it then stops about 1 cm from the sciatic notch on the lateral surface. The medial surface is cut just above the horizontal limb of the triradiate cartilage. The more of the medial surface that is left intact, the more lateral coverage the osteotomy provides. D. AP radiograph.

 

 

Risk factors include breech position, female, firstborn, and oligohydramnios. Developmental hip dysplasia is associated with other “packaging disorders.”

 

Patients with a history of hip dysplasia are typically followed with radiographs until adulthood to ensure normal acetabular development.

 

Asymptomatic older children without a prior history of developmental hip dysplasia may be diagnosed on incidental radiographs taken for other reasons in cases of mild dysplasia or by history or clinical examination in those children who become symptomatic.

 

Symptomatic patients will present in childhood with one or more features including hip pain, limp, limb length discrepancy, or asymmetric hip abduction, particularly those with underlying neuromuscular conditions.

 

 

Routine screening for hip dysplasia using radiographs is widely performed in neuromuscular conditions. Examinations and tests to perform include the following:

 

 

Ortolani test: Positive if a clunk is felt as a dislocated hip reduces. Barlow test: Positive if a clunk is felt as a reduced hip dislocates.

 

Hip abduction: In a normal hip, abduction should be more than 60 degrees and symmetric. This may be the only abnormal sign in infants. A difference of 10 degrees or more is significant.

 

Galeazzi sign: A difference in thigh length is a positive result. A positive Galeazzi sign can indicate a dislocated hip, a short femur, or a congenital hip deformity.

 

Abnormal skin folds can occur in normal children but may alert the pediatrician to an underlying hip problem. This finding is neither highly sensitive nor specific.

 

Limp with ambulation, Trendelenburg sign, or limp associated with limb length discrepancy may be the only abnormal sign in older children.

 

IMAGING AND OTHER DIAGNOSTIC STUDIES

 

Dynamic hip ultrasound can be used to detect hip dysplasia in very young infants (younger than 6 months of age).

 

Plain radiographs, including an anteroposterior (AP) view of the pelvis, frog lateral, and false-profile views, typically can be used to make the diagnosis in older children.

 

 

Radiographic parameters, including the acetabular index, lateral center-edge angle, anterior center-edge angle, the position of the sourcil, and the line of Shenton, should be evaluated (FIG 3).

 

 

Dislocation is defined by lack of contact between the acetabulum and femoral head. Subluxation is defined by a break in the line of Shenton.

 

Dysplasia is defined by a decrease in the lateral center-edge angle or an increased acetabular index on the AP pelvic radiograph or a decrease in the anterior center-edge angle on the false-profile view.

 

An AP pelvic radiograph taken with the legs abducted and internally rotated may show reduction of the femoral head implying that combined pelvic and femoral osteotomy would be expected to increase acetabular

coverage.

 

A computed tomography (CT) scan, particularly with three-dimensional (3-D) reconstruction can provide a more detailed evaluation of anterior and lateral coverage.

 

DIFFERENTIAL DIAGNOSIS

Slipped capital femoral epiphysis Legg-Calvé-Perthes disease Congenital coxa vara

Proximal femoral focal deficiency

 

 

NONOPERATIVE MANAGEMENT

 

Infants are typically treated with full-time braces, such as the Pavlik harness.

 

 

P.896

 

 

 

FIG 3 • A. Preoperative AP pelvic radiograph of a child with bilateral hip dislocations. B. Preoperative AP pelvic radiographs of a child with right hip dysplasia. This child underwent a closed reduction and adductor tenotomy at 12 months of age. The hip remains subluxated with persistent acetabular dysplasia and did not improve over a year of observation. Changes consistent with avascular necrosis are present in the right femoral epiphysis.

 

 

Young children can be treated with closed reduction and cast immobilization.

 

The initial treatment for primary acetabular dysplasia without hip instability or residual acetabular dysplasia following treatment for instability is observation.

 

 

As long as the acetabular index continues to improve and the hip remains concentrically reduced, observation can be continued.

 

If hip subluxation develops or the acetabular index fails to improve over a 12-month period, operative treatment is indicated.

 

Neuromuscular patients with a migration index less than 25% can be observed as long as their abduction

remains greater than 45 degrees. Patients with migration indexes over 50% generally will benefit from surgical treatment of their dysplasia, which can include a femoral or pelvic osteotomy.

 

SURGICAL MANAGEMENT

 

The Pemberton and Dega osteotomies are incomplete transiliac osteotomies used to treat acetabular dysplasia with anterior and lateral deficiencies.

 

They are used when more than 10 degrees of acetabular index correction is needed.

 

They are also used to increase femoral head coverage during open reduction in a patient with severe acetabular dysplasia.

 

Preoperative Planning

 

Hip and knee contractures should be carefully evaluated preoperatively so they can be addressed during the surgical procedure.

 

With neuromuscular patients, the femoral head may be deformed. An open capsulotomy to look at the articular cartilage may prove to be beneficial.

 

 

If there is significant articular cartilage damage, particularly laterally from the hip capsule, a resection arthroplasty may be indicated as opposed to a reduction.

 

The primary area of acetabular deficiency needs to be determined to plan the osteotomy.

 

The triradiate cartilage should be opened because the osteotomy hinges on this cartilage. Generally, this osteotomy can be performed up to about age 10 to 12 years. After this age, hinging is less likely to occur at the triradiate cartilage and moves significantly to the symphysis pubis, resulting in less reshaping and more reorienting of the acetabulum.

 

Hip mobility must be good, especially abduction and internal rotation.

 

A concentric reduction of the femoral head in the acetabulum before the osteotomy is an absolute prerequisite. This can be assessed preoperatively with an abduction internal rotation hip radiograph or can be assessed intraoperatively after an open reduction or varus proximal femoral osteotomy.

 

Positioning

 

Patients are positioned supine on a radiolucent table with a bump under the lumbosacral spine to provide about 30 degrees of elevation of the ipsilateral hip (FIG 4).

 

 

A fluoroscopic evaluation should be done at this time to ensure adequate radiographic visualization. The entire limb is prepared from the lower rib cage to midline.

Approach

 

A standard anterolateral approach using the interval between the tensor fascia lata and sartorius is used.

 

 

 

FIG 4 • Patient positioning. A bump is placed under the lumbosacral area, and the entire lower extremity is draped free.

 

 

P.897

 

 

 

TECHNIQUES

• Incision and Superficial Exposure for Both Osteotomies

  Two different skin incisions have been described. The choice is determined by the need for concomitant femoral osteotomy but is fundamentally surgeon preference.

  An anterolateral curvilinear incision starts 1 cm inferior and posterior to the anterior superior iliac spine (ASIS) extending distally over the greater trochanter down the proximal femur. This incision is only used when anterior open reduction and femoral osteotomy is included. It is expansile and provides excellent visualization for all aspects of an open reduction combined with pelvic and femoral osteotomy (TECH FIG 1A).

  Alternatively, a “bikini” oblique incision can be used, particularly if Dega or Pemberton osteotomy is done in isolation. This incision is more cosmetically appealing than the anterolateral curvilinear incision if the pelvic osteotomy is done in isolation. A separate additional lateral incision is used if femoral osteotomy is planned (TECH FIG 1B,C).

   

  TECH FIG 1 • Skin incisions. A. An anterolateral curvilinear incision starts 1 cm inferior and posterior to the ASIS extending distally over the greater trochanter down the proximal femur. B,C. The more limited

  bikini incision provides plenty of exposure for the pelvic osteotomy, leaves an unassuming scar, and can be combined with a lateral incision for concurrent femoral osteotomies.

   

   

  The skin incision is deepened to expose the iliac crest and the interval between the sartorius and tensor fascia lata.

   

  The deep fascia is incised just lateral to the tensor fascia lata muscle to avoid injury to the lateral femoral cutaneous nerve, and the sartorius muscle is released from its origin on the ASIS.

   

  The tensor-sartorius interval is deepened until the straight head of the rectus femoris is encountered at its origin on the anterior inferior iliac spine (AIIS). The straight head is generally released at its origin if concomitant anterior open reduction is done but can be left intact if only a pelvic osteotomy is done. If released, it is repaired during closure.

• Pemberton Osteotomy

Deep Exposure

 

The exposure is important in this osteotomy. Before any cuts are made, the surgeon should be able to clearly see the inner and outer portions of the iliac wing to the sciatic notch posteriorly and the entire hip capsule anteriorly.

 

The outer table of the ilium can be exposed either by splitting the iliac apophysis or by dissecting just below the apophysis, in which case, the apophysis is then taken off as an entire piece to minimize injury to this growth area.

 

The outer and inner tables are exposed in a subperiosteal fashion to the sciatic notch.

 

Chandler retractors are placed into the sciatic notch from medial and lateral to protect the neurovascular bundle (TECH FIG 2).

 

The reflected head of the rectus is then released and followed posteriorly. It acts as a guide to the border of the hip capsule.

Creating the Osteotomy

 

The first cut is made on the outer table starting 1 to 1.5 cm above the AIIS and extending posteriorly and parallel to the joint capsule.

 

About 0.5 to 1 cm from the sciatic notch, the osteotome should be turned and directed distally down the ischium to the level of the ischial limb of the triradiate cartilage (TECH FIG 3A).

 

The last portion of this cut is made in a blind fashion with fluoroscopic guidance, and care must be taken to avoid cutting into the sciatic notch, the hip joint, or the triradiate cartilage.

 

 

 

TECH FIG 2 • Deep exposure. The medial and lateral portions of the iliac wing have been exposed by splitting the apophysis. The Chandler retractors are in the sciatic notch. The capsule has been exposed. The direct head of the rectus is tagged with the suture.

 

 

The osteotome should remain midway between the capsular attachment and the sciatic notch, splitting the posterior column in half to the level of the triradiate cartilage.

 

The inner cut is started at the same point as the outer cut on the anterior surface, and the cut is generally at the same level as the outer cut running parallel to it (TECH FIG 3B).

 

P.898

 

 

 

TECH FIG 3 • A. Lateral wall cut. The Chandler retractor is in the sciatic notch and the osteotome is used to cut the lateral cortex. The cut has started between the ASIS and AIIS and is extending parallel to the joint.

The posterior portion of this osteotomy will be made in a blind fashion. B. Medial wall cut. The Chandler

retractor is in the sciatic notch, and the osteotome is used to cut the medial cortex. The cut has started at the same location as the lateral wall cut, between the ASIS and the AIIS, and is extending in the same direction as the lateral wall cut.

Osteotomy Variation

 

If more lateral coverage is needed, the inner cut is moved more distal and shortened to make a more oblique osteotomy.

 

This changes the fulcrum of rotation from straight posterior to more posteromedial, giving more lateral coverage as the fragment is levered downward (TECH FIG 4).

Separating the Bone

 

A special curved osteotome (TECH FIG 5A) is inserted into the osteotomy to connect the two cuts. This osteotome is advanced by hand.

 

Once the osteotome is at the level of the triradiate cartilage (TECH FIG 5B), the acetabular roof is gently levered down (TECH FIG 5C).

 

 

 

TECH FIG 4 • Variations in the Pemberton osteotomy. The inner and outer iliac wing cuts determine the amount of coverage based on their direction. A,B. If more anterior coverage is required, then the inner cut is more transverse. C,D. If more lateral coverage is required, then the osteotomy is inclined laterally and both cuts begin a little farther away from the capsule.

Graft Placement and Closure

 

Once the roof is in the desired position (usually an opening of 1 to 2 cm anteriorly), bone wedges are placed in the opening to hold the osteotomy open. Allograft or a wedge of the ASIS can be used.5

 

An autograft wedge of the ASIS can be harvested with a straight cut of the ilium (TECH FIG 6A).

 

The graft is usually placed from anterior to posterior. A gouge may be used to make a trough in the iliac wing and the acetabular fragment for the graft to rest in (TECH FIG 6B).

 

Internal fixation is usually not necessary.

 

 

The apophysis and muscles are then reattached with suture, and the skin is closed in routine fashion. A hip spica cast is then applied (TECH FIG 6C).

 

P.899

 

 

 

TECH FIG 5 • A. Pemberton osteotome. The special curved Pemberton osteotome is necessary to connect the inner and outer wall cuts and make the sharp posterior curve. B. Connecting the cuts. A special curved osteotome is necessary to make the sharp curve of the osteotomy posteriorly. The osteotome is advanced by hand, connecting the inner and outer wall cuts made previously. The osteotome is advanced to the level of the triradiate cartilage. The dotted line represents the ASIS autograft fragment that can be used to hold the osteotomy open. C. Levering down the osteotomy. The osteotomy is levered downward with the osteotome. A lamina spreader can also be used with caution. In this patient, a femoral shortening osteotomy and open reduction have been performed and sutures are in place allowing for a capsulorrhaphy once Pemberton osteotomy has been completed.

 

 

 

TECH FIG 6 • A. ASIS autograft bone wedge. An osteotome is used to harvest the ASIS autograft bone wedge. The height of the wedge is determined by the amount the osteotomy will be levered downward. B. Graft placement. An autograft bone wedge from the ASIS or an allograft wedge can be used. The graft is

inserted in an anterior to posterior direction and should be stable after it is impacted. Internal fixation is seldom necessary. C. AP postoperative pelvic radiograph of a left Pemberton osteotomy in a spica cast. An open reduction, capsulorrhaphy, and femoral shortening osteotomy have also been performed.

• Dega Osteotomy

Exposure

 

The abductor muscles are reflected off of the lateral cortex of the ilium just distal to the iliac apophysis. The apophysis itself is neither split nor taken off of the ilium in order to maintain normal apophyseal growth.

 

The outer table is exposed subperiosteally back to the sciatic notch. A blunt adult size Hohmann retractor is inserted into the notch laterally to provide visualization of the notch during the osteotomy.

 

Neither the muscles nor the periosteum is dissected off of the inner wall of the ilium. Their preservation is thought to aid in bone graft consolidation (TECH FIG 7).

 

 

P.900

 

 

 

TECH FIG 7 • Intraoperative photo of a right hip with the patient's head to the left showing complete exposure of the lateral ilium, Hohmann retractor in the notch posteriorly, guidewire at the superior aspect of the osteotomy, and x mark where osteotomy will end 1 cm in front of notch. It is essential to clearly see the notch during use of the chisel to make the bone cut and to lever open the osteotomy.

Creating the Osteotomy

 

A curvilinear osteotomy is performed on the outer wall starting just above the AIIS to end at a point 1 to

1.5 cm in front of the sciatic notch. The exact level of the osteotomy on the ilium is determined by the steepness of the acetabulum and is usually about 1 to 2 cm above the capsular insertion.

 

A guidewire is inserted at the most cephalad portion of the osteotomy directed to exit just above the horizontal limb of the triradiate cartilage. The guidewire is placed under radiographic guidance and adjusted as needed to end at the triradiate cartilage. A line is drawn on the ilium, based on the guidewire, and serves as the directional guide for the chisel as the osteotomy is made (TECH FIG 8A-D).

 

A straight 0.25- or 0.5-inch (0.64- or 1.3-cm) osteotome is used to cut the ilium obliquely medially and inferiorly in line with the guidewire to exit through the inner wall above the iliopubic and ilioischial limbs of the triradiate cartilage but leaving the sciatic notch and posterior one-third of the inner cortex intact to act as a fulcrum for rotation (TECH FIG 8E,F).

 

The cortex is levered down with a wide osteotome to provide the desired coverage. A small laminar

spreader is also useful for this maneuver (TECH FIG 8H-I).

 

The amount of lateral and anterior coverage is determined by how much of the medial inner cortical wall is left intact.

 

If more of the medial wall is left intact, then fulcrum of rotation will move more anterior and more lateral coverage will be obtained (TECH FIG 9A,B).

 

If more of the medial wall is cut, the fulcrum of rotation will move posteriorly and more anterior coverage will be obtained (TECH FIG 9C,D).

 

 

 

TECH FIG 8 • A-D. Guidewire placement. A. Intraoperative fluoroscopy image showing that initial placement of guidewire is too superior. B. The guidewire is redirected more obliquely to end at the correct point just above the triradiate cartilage. C. Another example of proper guidewire placement ending just above the triradiate cartilage. D. Guidewire placement and osteotomy mapping line on outer ilium. (This is the left hip and the patient's head is to the right.) The guidewire is always placed at the most cephalic point of the osteotomy and verified to be in the correct plane by C-arm fluoroscopy. The mapping line is then drawn off of the guidewire. A curvilinear osteotomy is performed on the outer wall starting just above the AIIS to a point 1 to 1.5 cm in front of the sciatic notch. E. Right hip with ½-inch osteotome in osteotomy plane. The guidewire is removed once the correct plane of the osteotomy has been created. The progression of the osteotomy is checked by fluoroscopy but can be visualized grossly. F. Intraoperative fluoroscopy showing correct orientation of the chisel prior to removal of the guidewire. (continued)

 

 

P.901

 

 

 

TECH FIG 8 • (continued) G. Right hip with osteotome levering open the osteotomy. Note the intact posterior sciatic notch at bottom of picture, which acts as a fulcrum for rotation and provides recoil for graft stability. H. Intraoperative fluoroscopic view showing osteotomy levered open by osteotome. I. Separate example of a small lamina spreader used to open the osteotomy.

Graft Placement and Closure

 

Triangular or trapezoidal bone wedges, either autogenous or allograft, are used to hold the osteotomy open. Autograft wedges are harvested from a concurrent femoral shortening osteotomy or from the iliac crest. When larger grafts are required, a freeze-dried fibular allograft works well (TECH FIG 10A-D).

 

The wedges are inserted in a manner that places the largest graft where the most coverage is desired. Smaller grafts are then added as needed to fill the defect (TECH FIG 10E-G).

 

 

 

TECH FIG 9 • 3-D CT preoperative reconstruction. Viewed from anterior oblique direction, the blue arrow denotes the direction of osteotomy so that the anterior end point of the osteotomy on the inner wall

leaves the posterior two-thirds of the inner cortex intact. Lateral coverage is optimized (A). Viewed from inner pelvis, the blue line denotes the amount of inner cortex that is cut when lateral coverage is emphasized (B); when more anterior coverage is desired, more of the inner cortex is cut. Green arrow points toward a more posterior end point on the anterior view (C); when viewed from the inner side, green line marks the extent of inner cortical cut when anterior coverage is emphasized (D).

 

 

The grafts are stable and internal fixation is not necessary because of the inherent recoil at the osteotomy site produced by the intact sciatic notch.

 

 

The apophysis and muscles are then reattached with suture, and the skin is closed in routine fashion. A hip spica cast is then applied.

 

P.902

 

 

 

TECH FIG 10 • Bone grafting. Triangular or trapezoidal pieces of autograft or allograft bone can be used as wedges. The size of the wedge depends on the amount the osteotomy is mobilized and the remaining gap left. Autograft bone wedges from a femoral shortening (A) or harvested from bicortical iliac crest (B,C) are used. D. In cases in which a substantial gap is created, freeze-dried fibular allograft cut into trapezoidal sections is helpful. The largest wedge is inserted in the area where the largest amount of coverage is desired. The grafts should be stable after they are impacted as long as the sciatic notch has not been violated. Internal fixation is not necessary. E-G. Examples of other grafts. E. Right hip with head at top showing three stable trapezoidal bicortical iliac crest grafts. F. Corresponding intraoperative fluoroscopic image of the grafts. G. Use of femoral autograft.

 

 

 

PEARLS AND PITFALLS

 

Inadequate exposure of sciatic notch

• For the Dega, if the sciatic notch is not exposed, a Hohmann retractor not inserted in the notch, and the osteotomy is not stopped at least 1 cm short of the notch, disruption can occur resulting in instability at the graft site and inability to reshape the acetabulum.

   

  Need lateral coverage

  • For the Dega, the osteotomy should be more of an oblique osteotomy starting higher on the ilium and the length of the inner wall cut should be much less than the length of the outer cut. This allows the osteotomy to rotate around a more medial fulcrum, giving more lateral coverage.

     

    Need anterior coverage

  • For the Pemberton, the inner and outer wall cuts should be on the same level and the two cuts should be about the same length. For the Dega osteotomy, the inner cut might be slightly shorter (no less than 75% of the length of the outer cut). These considerations allow either osteotomy to rotate around a more posterior fulcrum, giving more anterior coverage.

     

    Graft loosening

  • A gouge can be used to make a trough for the graft.

  • Pemberton: The stability of the graft is tested with a Kocher clamp. If it is unstable, then the osteotomy is secured with a temporary Kirschner wire. The Kirschner wire must remain extra-articular.

  • Dega: The largest graft is placed in the area that needs the most coverage. The outer cortex of the graft should be buried below the outer cortex of the ilium.

     

    Entry into the acetabulum

• Without careful fluoroscopic guidance, the osteotome can be directed into the acetabular cartilage, causing significant damage.

   

  Excessive anterior coverage

  • In a patient with prolonged subluxation or significant retroversion, the anterior coverage may subsequently leave the posterior acetabulum more unstable.

 

 

P.903

 

 

 

FIG 5 • Example of Dega osteotomy done in conjunction with anterior open reduction and femoral shortening in a toddler. A. Preoperative radiograph showing complete dislocation. B. Immediate postoperative radiograph following open reduction, femoral shortening, and Dega pelvic osteotomy. C. Three-year follow-up showing very satisfactory coverage.

 

POSTOPERATIVE CARE

 

Patients are almost exclusively treated with a hip spica cast for 6 to 12 weeks. If this is a staged procedure, the patient should be left in half of the spica cast while the second procedure is being done.

 

Radiographs are obtained to make sure graft displacement has not occurred.

 

Once good radiographic healing has been demonstrated, progressive weight bearing over 4 weeks can be started.

 

Children are followed until maturity to detect avascular necrosis and ensure adequate acetabular coverage.

 

Physical therapy is typically not needed to regain mobility after immobilization.

OUTCOMES

The Pemberton osteotomy provides excellent long-term acetabular correction in children, particularly those younger than age 4 years.3, 7, 8, 12, 13

The osteotomy has also been effective in patients with neuromuscular dysplasia.10

The Dega osteotomy has been successfully used in the treatment of developmental dysplasia of the hip and neuromuscular dysplasia (FIG 5).

Several studies have found excellent results in younger children (younger than age 6 years), with results in older children less reliable.4, 9

 

 

COMPLICATIONS

Stiffness

Subluxation or dislocation

Late recurrence of dysplasia either femoral or acetabular Closure of triradiate cartilage

Chondrolysis

Avascular necrosis of the femoral head

 

 

REFERENCES

1. Dega W. Osteotomis trans-iliakalna w leczeniu wrodzonej dysplazji biodra. Chir Narzadow Ruchu Ortho Pol 1974;39:601-613.

    

    

2. Dega W, Krol J, Polakowski L. Surgical treatment of congenital dislocation of the hip in children; a one-stage procedure. J Bone Joint Surg Am 1959;41-A(5):920-934.

    

    

3. Faciszewski T, Kiefer GN, Coleman SS. Pemberton osteotomy for residual acetabular dysplasia in children who have congenital dislocation of the hip. J Bone Joint Surg Am 1993;75(5):643-649.

    

    

4. Grudziak JS, Ward WT. Dega osteotomy for the treatment of congenital dysplasia of the hip. J Bone Joint Surg Am 2001;83-A(6): 845-854.

    

    

5. Kessler JI, Stevens PM, Smith JT, et al. Use of allografts in Pemberton osteotomies. J Pediatr Orthop 2001;21:468-473.

    

    

6. Ozgur AF, Aksoy MC, Kandemir U, et al. Does Dega osteotomy increase acetabular volume in developmental dysplasia of the hip? J Pediatr Orthop B 2006;15:83-86.

    

    

7. Pemberton PA. Pericapsular osteotomy of the ilium for the treatment of congenital subluxation and dislocation of the hip. J Bone Joint Surg Am 1965;47:65-86.

    

    

8. Pemberton PA. Pericapsular osteotomy of the ilium for the treatment of congenitally dislocated hip. Clin Orthop Relat Res 1974; (98):41-54.

    

    

9. Reichel H, Hein W. Dega acetabuloplasty combined with intertrochanteric osteotomies. Clin Orthop Relat Res 1996;(323): 234-242.

    

    

10. Shea KG, Coleman SS, Carroll K, et al. Pemberton pericapsular osteotomy to treat a dysplastic hip in cerebral palsy. J Bone Joint Surg Am 1997;79(9):1342-1351.

     

     

11. Slomczykowski M, Mackenzie WG, Stern G, et al. Acetabular volume. J Pediatr Orthop 1998;18:657-661.

     

     

12. Vedantam R, Capelli AM, Schoenecker PL. Pemberton osteotomy for the treatment of developmental dysplasia of the hip in older children. J Pediatr Orthop 1998;18:254-258.

     

     

13. Wada A, Fujii T, Takamura K, et al. Pemberton osteotomy for developmental dysplasia of the hip in older children. J Pediatr Orthop 2003;23:508-513.