Background: Patellar instability is a common problem in Down syndrome patients since their childhood. Several treatment have been proposed, but relapses are frequent and not all surgeries are suitable for growing patients. The aim of the present study is to evaluate the clinical and radiographic outcomes of a modified Roux-Goldthwait technique, for the management of patellar instability in children with Down syndrome at minimum 5-year followup.
Materials and Methods: 19 patients (23 knees) affected by Down syndrome surgically treated for patellar dislocation, between 2000 and 2012 were included in this study. The mean age of patients was 9.5 years (range 3.7 - 15 years) and had a Dugdale Grade III, IV, and V patellar dislocation. Trochlear groove dysplasia was present in 15 patients. Each patient was clinically evaluated considering relapse rate, pre- and postoperative range of motion (ROM), Kujala score, and modified Lysholm score. Radiographic examination was performed on standard X-ray considering patellar height, trochlear angle, and patellofemoral congruence angle.
Results: The mean followup was 134 months (range 62-206 months). No case of relapse of dislocation was registered with an improved ROM (significant for knee extension, P < 0.05). The Kujala score showed significant improvement from a mean preoperative value of 39 ± 6.3 to a mean postoperative value of 92.7 ± 3.4 (P < 0.05) at final followup such as the modified Lysholm score (from mean preoperative 55.6 ± 6.3 to mean postoperative of 94.2 ± 2.6). Radiographs performed at latest followup showed a tendency to normalization of all the parameters considered, with a restored patellofemoral congruence and trochlear groove shape and without signs of osteoarthritis.
Conclusion: The present study showed that the Roux-Goldthwait procedure is a valid surgical option for the treatment of patellar dislocation in children with Down syndrome.