Specific features of orthopedic pathology in neurofibromatosis type I patients of the Republic of Bashkortostan

Background Neurofibromatosis type 1 (NF-1) is a hereditary tumor syndrome characterized by cutaneous, subcutaneous and plexiform neurofibromas, optic nerve gliomas, cognitive disorders and can be associated with orthopedic pathology. Clinical manifestations of NF-1 include skeletal abnormalities requiring a specific approach to treatment of the tumor-like processes in the involved bones and joints.

The objective was to determine the frequency of orthopedic pathology and clinical manifestations of the disease in NF-1 patients seen in the Republic of Bashkortostan (RB) and make international comparisons.

Material and methods Outpatient records of patients with a clinical diagnosis of NF-I, the results of laboratory and  instrumentation studies were examined. A retrospective analysis of the frequency of  occurrence of the main clinical manifestations of NF-1 and orthopedic pathology was conducted. An interactive 2 × 2 contingency table was used for calculation of association statistics (Pearson χ² criterion) with the Yates correction for continuity developed by V.P. Leonov and four-field contingency tables were analyzed.

Results and discussion The incidence rate of NF-1 was 1:7407 by 2024 in the RB, which is 2.3 times less than the world average (1:3000 people). Associated malformations included scoliosis seen in 17.4 %, chest deformity observed in 5.3 %, pseudoarthrosis in 3 %, facial dysmorphism in 9 %, short stature in 13.8 % of patients. Osteoporosis, facial asymmetry and sphenoid wing dysplasia were not observed in NF-1 patients in the region. A statistically significant difference in the frequency of occurrence of orthopedic pathology was determined in patients with NF-1 from the RB using four-field contingency tables. A retrospective analysis showed a statistically lower incidence of orthopedic pathology in NF-1 patients of RB as compared to the world average which indicated the need to include orthopedic consultation in medical and economic standards for the timely detection of pathology and treatment.

Conclusion Analysis of orthopedic pathology in NF-1 patients from RB showed the occurrence of  chest deformity, scoliosis, short stature and pseudoarthrosis being comparable with world data. Skeletal anomalies, facial dysmorphism and macrocephaly were not common for NF-1 patients of RB. No cases of osteoporosis, facial  asymmetry and sphenoid wing dysplasia being characteristic of NF-1 patients were detected in  the  patients. Learning difficulties were more common for NF-1 patients with orthopedic pathology as compared to NF-1 patients of RB.

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