Waldenström classification: Better evaluation for the intervention time of scottish rite brace treatment in legg-calve-perthes disease

Objective: To evaluate the outcome of the scottish rite brace treatment by classifications and if so in what phase the optimal intervention time is. Methods: We retrospectively reviewed 43 patients (48 hips), aged from 5-15, who had LCPD and accepted scottish rite brace treatment between December 1996 and October 2012. Mean follow-up is 5.75 years (range, 2.58-14.08 years). The radiographic images of osteonecrosis were evaluated in our institution. We investigated the potential prediction of several classification systems by Kruskal-Wallis rank sum test and Nemenyitest, including Catterall Grouping, Herring Lateral Pillar Sign, Waldenström classificationand so on. Results: The clinical effective rate in modified Stulberg classification (type I & II) was 85.4% and the excellent rate (ER) was 56.3%. The children younger than eight years old showed an ER of 80% compared to 45.5% in the elder ones. The cases of Catteralltype I & II group presented an ER of 77.8% which was higher than that of III & IV type group (43.3%). In Herring classification, ER of type A group was 100%, ER of type B group was 62.5% and ER of type C group was 25%. In osteonecrosis phase, the patients were proved to be better with an ER of 56.5% than those patients in the fragmentation phase (0%) and reossification phase (77.8%) (P < 0.05). Among them, the differences between A and C were statistically significant in Haring classification (P < 0.05); the difference between osteonecrosis phase and the repair phase in Waldenstrom’ was not statistically significant (P > 0.05); but those two groups were significant different with fragmentation phase (P < 0.05). Conclusions: The scottish rite brace treatment used on particular phases of Perthes’s in children are advised to have a better outcome. The fragmentation and necrosis phase showed a worse result than reossification one. The optimal intervention times are tended to be the earlier phases in the disease progress according to Waldenström’s. Orthopedic surgeons can resort and refer to the optimal times mentioned above and make the most of scottish rite brace treatment, even if those indexes are required to be addressed infuture randomized trials.