Congenital dislocation of the patella (CPD). Surgical treatment rationale and literature review

Case Report: We report a case of bilateral CDP associated with bilateral proximal radioulnar joint stiffness; the patient at the age of diagnosis was 11 years old and underwent a bilateral delayed surgical procedure; the 4-year follow-up results are satisfactory. Surgical treatment rationale and literature are reviewed. Introduction: Congenital dislocation of the patella (CDP) is a rare condition and its treatment is not well defined. In CDP, patella is dislocated on the lateral aspect of the distal femur, laterally from the trochlear groove, it cannot be reduced manually and it is almost always associated with genu valgum, lateral torsion of the proximal tibia, and flexion contracture of the knee. This condition is present at birth, but the clinical findings can be subtle at birth due to the size and character of the structures being examined; early diagnosis is essential, but it may be delayed to late childhood or adulthood. If CDP is not promptly treated, the disability increases during growth, so surgical correction should be planned as soon as the diagnosis is confirmed. Conclusion: Surgical correction for CDP is generally recommended, but there is no agreement in literature on the ideal treatment and in some cases, with mild impairment of the knee function, observation alone has been suggested. The decision about a surgical treatment can be difficult and depends on the degree of disability of the patient. Keywords: Congenital dislocation of the patella, bilateral congenital dislocation, patella, Z-plasty quadriceps muscle, lateral retinaculum release, lack of active knee extension.