Orthopaedic manifestations of Proteus syndrome in a child with literature update

Abstract

Background: Proteus syndrome is a rare developmental disorder of unknown aetiology. It is a disorder characterized by postnatal overgrowth affecting multiple tissues. Proteus syndrome is most frequently manifested in skeletal changes. As manifestations of Proteus syndrome are highly variable, and many are found in other overgrowth syndromes, and due to inconsistent application of diagnostic criteria, the literature has more reports of patients misdiagnosed than correctly diagnosed. The purpose of this study is to report the clinical and radiographic patterns of affection of the musculoskeletal system in Proteus syndrome in the light of the proposed diagnostic criteria and cases reported in the literature.

Methods: The clinical and radiographic musculoskeletal characteristics of a child with Proteus syndrome are illustrated along with a literature update. The orthopaedic manifestations in our patient are correlated to cases and proposed diagnostic criteria reported in the literature.

Results: The study of the presented case and review of available literature show that there tends to be a highly characteristic pattern of skeletal abnormalities in Proteus syndrome.

Conclusion: The rarity of Proteus syndrome and the variability of signs make the diagnosis challenging. Clinical and radiographic examinations are important contributors to the diagnosis. The clinical utility of the reported cases is significantly dependent on consistent application of diagnostic criteria that augment diagnostic accuracy. The present case reinforces the need for supplementary musculoskeletal imaging modalities to be implemented in the diagnosis of Proteus syndrome.

Keywords: Musculoskeletal; Overgrowth syndromes; Rare bone disease.

Graphical abstract

Fig. 1

(A, B, C): A five year old boy with Proteus syndrome. Note the generalized overgrowth, upper and lower limb length discrepancy, localized limb distortion of the left knee (A), postural flexion deformity of the left knee (B), and mild dorsal scoliotic deformity (C).

Fig. 2

Limb length discrepancy was mostly femoral.

Fig. 3

Plain radiographs of the left knee, lateral view. Note the increased soft tissue shadow (white arrows) and para patellar hyperostosis (black arrows).

Fig. 4

(A, B): Macrodactyly of the left index and thumb. Note the finger distortion (A), and retained shape and contour of the enlarged bones of the first and second ray (B).

Fig. 5

(A, B): Anteroposterior radiographs of both knees (A) pelvis and both hips (B) demonstrating left para patellar hyperostosis. Note the relatively normal contour of the involved bones around the knees and hips.

Fig. 6

(A, B): Anteroposterior view (A) and lateral view (B) of the dorsal spine. Note the presence of abnormal vertebrae in both views and mild scoliotic curve to the left (A) and distorted sagittal alignment (B).