Congenital knee dislocation: conservative management of a series of cases

Lucía Rodríguez-Noriega-Béjar, Unidad de Neonatología, Hospital Universitario Central de Asturias, Oviedo, España
Cristina Martínez-García, Unidad de Neonatología, Hospital Universitario Central de Asturias, Oviedo, España
Carmen Ornia-Fernández, Unidad de Neonatología, Hospital Universitario Central de Asturias, Oviedo, España
Andrea Cabeza-Antuña, Unidad de Neonatología, Hospital Universitario Central de Asturias, Oviedo, España
Mara Rodríguez-Ortiz, Unidad de Neonatología, Hospital Universitario Central de Asturias, Oviedo, España
Gonzalo Solís-Sánchez, Unidad de Neonatología, Hospital Universitario Central de Asturias, Oviedo, España

Background: Congenital knee dislocation (CKD) is a rare musculoskeletal anomaly characterized by hyperextension of the knee at birth. Its possible etiologies include mechanical factors, such as oligohydramnios or breech presentation, as well as genetic or neuromuscular abnormalities. The objective was to describe the incidence, clinical characteristics, management, and outcomes of CKD cases diagnosed in a neonatal unit in northern Spain over a 20-year period. Methods: We conducted an observational, descriptive, and retrospective study including all cases of congenital knee dislocation diagnosed between 2005 and 2024 (43,500 live births). Demographic, obstetric, clinical, therapeutic, and complication variables were analyzed based on medical records and diagnostic imaging. Results: Eight patients (11 affected knees) were identified, with an inci-dence of 0.02%. The mean gestational age was 37 weeks, and the mean birth weight was 2,435 grams. Seventy-five percent of patients were female, with bilateral involvement in 37.5% and a predominance of left-sided dislocation. Oligohydramnios was observed in 25% of cases and breech presentation in 37.5%. Developmental dysplasia of the hip was the most frequent comorbidity (37.5%). All patients were treated conservatively with serial casting, achieving favorable outcomes in six. One patient required prolonged orthotic management due to complex malformations, and another presented a mild limb-length discrepancy. Conclusions: Early diagnosis, typically through physical examination, is essential for a favorable prognosis. Conservative treatment is effective in most cases, while surgery should be reserved for refractory situations. The incidence observed was higher than previously reported, which may reflect methodological or population-based differences. Compre-hensive patient evaluation is crucial to identify associated anomalies and prevent long-term complications.

Keywords: Congenital knee dislocation. Oligohydramnios. Breech presentation. Developmental dysplasia of the hip. Pediatric orthopedics. Infant. Newborn.