Treating Perthes disease in children up to 5 years old leads to best results

Whether treated conservatively or surgically, most had excellent or good 25-year outcomes.

Children with onset of Perthes disease before 5 years old achieved the best radiographic results at long-term follow-up. This was the case whether patients were treated surgically or conservatively, according to Italian investigators who followed patients an average of 25 years.

"We didn't find any statistically significant correlation between the initial severity according to Catterall [classification] and the kind of treatment and the radiographical result according to Stulberg," Daniele Lazzara, MD, said at the 8th European Federation of National Associations of Orthopaedics and Traumatology Congress.

Osteotomies vs. casts

Clinicians saw the patients (121 hips) between 1963 and 1989 at the Orthopaedic and Traumatologic Center in Florence. They followed 41 hips for 25 years average (age range, 16 to 38 years).

Investigators originally managed 19 patients (20 hips) surgically using femoral valgus and derotational osteotomies or pelvic osteotomies. Twenty patients (21 hips) underwent nonoperative management — pelvi-podalic casts and no weight-bearing.

There were 19 boys in each group.

During the paper's discussion period, Lazzara said appropriate operative management of Perthes disease is still an open issue, but for his operative cases he usually performs a femoral osteotomy.

Predicting factor

Of the patients with onset of Perthes disease before 5 years old, most improved based on their Stulberg 1 and 2 radiographic evaluations at long-term follow-up, which included 86% of conservatively treated and 70% of operated patients, Lazzara said.

"In this series, the most important predicting factor was the age at onset of the disease," he said.

To arrive at the Stulberg scores, investigators used radiographs to evaluate such factors as femoral head size and neck length, acetabular slope based on Sharp's angle, and the percentage of femoral head covered by the acetabulum.

According to the original Catterall classification, 48% of the conservative group (6 cases) were class 1, 52% were class 3 (7 cases), and four patients each were class 2 or 4. Of the surgically managed patients, 40% were Catterall class 1 or 2 and 60% were class 3 or 4, "so they were worse cases," Lazzara noted.

Of the 23 Catterall class 3 or 4 cases, if the child was younger than 5 years old at the outset (11 cases), he or she developed into Stulberg 1 and 2 regardless of how they were treated, he said. In patients older than 5 years, six each were Stulberg class 1 and 2 or class 3 and 4 at final follow-up.

Investigators used the Harris hip score for their clinical evaluations. Both groups had similar clinical results: excellent and good, 86%; and fair or poor, 14%, Lazzara said.

For more information:
Daniele Lazzara, MD, can be reached at First Orthopaedic Clinic of the University of Florence, Largo P. Palagi, 1, Florence, Italy 50139. +39-55-7948074; e-mail: ortosec@unifi.it.
Lazzara D, DiMuria G, Marcucci M, Trombetta A. Perthes disease: A comparison between conservative and surgical treatment after an average follow-up period of 25 years. #F712. Presented at the 8th European Federation of National Associations of Orthopaedics and Traumatology Congress. May 11-15, 2007. Florence.