orthopedic

What is the Pavlik Harness Used for?

A: The Pavlik harness is often used as the initial treatment of hip dysplasia in infants, also know as developmental dysplasia of the hip (DDH).[1]

What is the Pavlik Harness?

It is a soft dynamic brace that maintains the hip in flexion (knee up towards the head) and abduction (knee away from the centerline). This position maintains the proper position of the femoral head and allows for “tightening up” of the ligamentous structures as well as for stimulation of normal formation and deepening of the hip socket.[2]

Congenital Hip Dislocations…

True dislocation of the hips occurs in about 1 in 1,000 births although as many as 1 in 100 may have clicky hips. When screening was initiated the incidence was found to be about 3 times that previously suspected, suggesting that 2 in 3 recover spontaneously. As we do not know which 2 in 3 these are and the implications for the third that does not recover are serious, it is wise to treat all. Some early work, published in 1962, suggested that 1 in 60 had unstable hips at birth, 60% of these became stable by 1 month and 88% by 2 months, leaving just 1 baby in 500 with unstable hips after 2 months. Neonatal screening for CDH has been national policy in the UK since 1969.

Risk Factors…

• There are racial differences. In the USA it is found that native Americans andLaplanders have a high incidence whilst Chinese and African Americans have a low incidence.
• Positive family history of the condition increases the risk in a manner suggestive of multifactorial inheritance.
• About 80 to 85% are female.
• About 60% of cases are first-born, compared with about 40% of all babies.
• Breech presentation increases the risk of CDH. The extended breech position in which knees are extended is a higher risk than with knees flexed. Elective caesarian section reduces the risk compared with vaginal breech delivery but it remains higher than after a cephalic presentation.
• Restriction of movement as with oligohydramnios increases the risk.
• It is commoner with neuromuscular disorders, such as cerebral palsy, meningomyelocele and arthrogryposis.
• The left hip is dislocated more often than the right. This is thought to be due to the common position of the baby’s left hip against the mother’s sacrum, restricting movement.
• In cultures that use swaddling of babies, forcing the hips into extension and adduction, it is more common.[3]

The Pavlik Harness…

The Pavlik harness should be placed such that the chest strap is at the nipple line with 2 finger-breadths of space between the chest and strap. The anterior strap is at the midaxillary line and should be set such that the hips are flexed to 100-110°. Excessive hip flexion can lead to femoral nerve compression and inferior dislocations. Quadriceps function should be determined at all clinic visits. The posterior abduction strap should be at the level of the child’s scapula and adjusted to allow for comfortable abduction. This should prevent the hips from adducting to the extent that the hips dislocate. Excessive abduction should be avoided because of concern regarding the development of avascular necrosis. Fitting should then be checked clinically within the first week and then weekly thereafter. Carefully monitoring the patient to ensure the harness fits and the hips are reduced is important.

Ultrasonography…

Ultrasonography is an excellent means of documenting the reduction of the hip in the Pavlik harness and should be performed early in the course of treatment (Suzuki, 1993). If the hip is posteriorly subluxed, then the Pavlik harness therapy should be discontinued. Using the Pavlik harness for guided reduction, which occurs when the hip does not completely reduce initially but is pointed towards the triradiate cartilage, is controversial.[4]

The US Preventative Service Task Force (USPSTF)…

The U.S. Preventive Services Task Force (USPSTF) recently concluded that evidence is insufficient to recommend routine screening for DDH in infants as a means to prevent adverse outcomes. Evidence shows that screening leads to earlier identification of DDH; however, the USPSTF concluded that 60 to 80 percent of the newborn hips identified by physical examination and more than 90 percent identified by ultrasonography as abnormal or as suspicious for DDH resolve spontaneously and require no intervention.

The long-term results of Pavlik harness treatment (e.g., nonoperative treatment) show a 95 percent success rate for acetabular dysplasia and subluxation.22,23 The success rate drops to 80 percent for frank dislocation.[5]

References:

1. Ramsey PL, Lasser S, MacEwen GD. Congenital dislocation of the hip. Use of the Pavlik harness in the child during the first six months of life. J Bone Joint Surg Am. 1976Oct;58(7):1000-4.
2. http://www.massgeneral.org/ortho/Hip_Dysplasia.htm.
3. http://www.patient.co.uk/showdoc/40024965/
4. http://www.emedicine.com/orthoped/topic456.htm.
5. http://www.aafp.org/afp/20061015/1310.html