The Weinstein-Ponseti Approach for Open Reduction in Teratologic Hip Dislocation
Teratologic hip dislocation is associated with very marked and advanced changes in the hip joint at the time of birth, with the hip in a fixed dislocated position. Teratologic hip dislocation is a rare deformity, with a reported incidence of 0.03 to 0.04 per 1,000 births. It is an atypical dislocation compared with most of the typical dislocations that occur in patients with developmental dysplasia of the hip associated with chromosomal abnormalities and other severe malformations.
Management of a teratologic hip dislocation is more difficult than management of a typical hip dislocation. The hips are firmly dislocated, stiff, and irreducible. The anatomic changes associated with teratologic hip dislocation are more severe than those associated with developmental dysplasia of the hip in patients of the same age. A paucity of information exists in the literature on the management of teratologic hip dislocation. Some studies report that bilateral dislocation should not be manged. We believe that these hips should be reduced to restore near-normal hip mechanics and decrease the risk of later pain and stiffness.
This video details the anteromedial approach to the hip first described by Weinstein and Ponseti. This approach has been used at the Iowa University Children's Hospital since the late 1970s. More than 200 patients with a congenital hip dislocation have been successfully treated via this approach, with more than 90% reporting fair to excellent results. The Weinstein-Ponseti anteromedial approach to reduce persistent hip dislocation was first described in 1979 as a variation of the Ludloff medial approach. This medial approach actually is more of an anterior approach performed through an anteromedial incision, in which the hip is approached in the interval between the pectineus muscle and the femoral neurovascular bundle. We propose this approach for patients with a teratologic hip dislocation because it affords an excellent view of the surgical field, is simpler and safer compared with other approaches, and is associated with a short learning curve. We have used arthroscopy to afford a better view of the surgical field.
This video discusses the case presentation of a preterm newborn (gestational age, 28 1/7 weeks) with a teratologic hip dislocation who has multiple congenital anomalies, abnormal facies, pericardial effusion, an echogenic bowel, a large liver, and clubfeet. The patient has multiple excessive skin folds, causing the anatomic landmarks to not be visible. The hip is frankly dislocated and was not reducible via closed procedures. The procedure is performed with the patient in the supine position. The hip is flexed to approximately 70° in unforced abduction, the neurovascular bundle is identified, and the superior and inferior borders of the adductus longus are palpated. The incision extends from the inferior border of the adductor longus to just inferior to the femoral neurovascular bundle in the groin crease. The adductor longus is isolated and sectioned. The anterior branch of the obturator nerve is identified as it crosses the adductor brevis muscle.
The interval between the pectineus muscle and the femoral neurovascular bundle is identified and bluntly dissected. Care must be taken during this dissection to avoid medial femoral circumflex artery injury. Retraction on the femoral neurovascular bundle must be gentle to avoid injury to the femoral vein, which is located directly under the retractor and the remainder of the neurovascular bundle. The iliopsoas tendon can be palpated just distal to the medial femoral circumflex artery. This is facilitated by externally rotating the leg until the lesser trochanter is easily palpable in the surgical field.
The iliopsoas tendon is isolated with the use of a curved hemostat and sectioned sharply with the use of a No. 15 blade at the insertion on the lesser trochanter. With gentle retraction on the femoral neurovascular bundle superiorly and on the pectineus muscle inferiorly, the hip joint capsule is isolated with blunt dissection. A small incision is made in the anteromedial hip joint capsule parallel to the anterior acetabular margin. The ligamentum teres can now be visualized. Using dissecting scissors in the interval between the ligamentum teres and the anteromedial joint capsule, the capsule is incised sharply and the ligamentum teres is excised sharply. The acetabulum can now be completely visualized. After the head is reduced, stability is assessed via intraoperative fluoroscopy. After the head is reduced and closure is complete, a cast is applied in the human position.
The advantages of this approach include direct access to obstacles to reduction, avoidance of damage to the iliac apophysis and the abductor muscles, minimal blood loss, the need for a single surgical session for management of both hips, and a cosmetically acceptable scar.