A 12-year-old boy presented to the orthopaedic clinic with reduced mobility secondary to bilateral lower limb swelling and severe episodic knee pain. He was noted to have bleeding gums and his examination revealed ecchymosis of both lower limbs. He proceeded to have x-rays and MRI scans of both limbs.
MRI scan shows low signal regions on the T1-weighted images which are parallel to the endplates within the distal femoral and proximal tibial metaphysis, which are similarly seen in the proximal fibula [Fig. 2]. Matching areas of increased signal on STIR sequence through the tibial shaft and ankle joint metaphysis are seen[Fig. 3 + Fig. 4]. High STIR signal can also be noted in the distal femur intercondylar notch with low signal on T1-weighted sequences [Fig. 5 + Fig. 6]. There are subperiosteal collections overlying the posterior aspect of distal femurs bilaterally [Fig. 7 + Fig. 8]. Features of myositis within the tibialis anterior muscle and subcutaneous oedema with high signal throughout the medial and lateral gastrocnemius muscles are seen [Fig. 9]. The high STIR sequences are reduced post-treatment, showing radiological improvement [Fig. 10A -11B].
Background
Scurvy is a clinical syndrome due to vitamin C deficiency (<11.4 µmol/L). Vitamin C is an essential co-factor required for the hydroxylation of proline and lysine and subsequent collagen synthesis. Its deficiency leads to the production of unstable pro-collagen chains predisposing to weakened bones and increased susceptibility to fractures.
In children, there are a number of risk factors associated with scurvy including malnutrition, malabsorption and neglect. Patients with neurodevelopment or psychiatric conditions are more likely to exhibit food selectivity [1,2]. Conditions that result in iron overload, such as thalassemia also deplete vitamin C causing scurvy [3].
Clinical Perspective
A thorough history including dietary habits and clinical suspicion is imperative to be able to diagnose scurvy. The early signs of scurvy are non-specific (fatigue, irritability and failure to thrive) with the classic symptoms of bleeding gums, ecchymosis, musculoskeletal pain and weakness presenting late. Severe prolonged deficiency can be life-threatening.
Imaging Perspective:
Radiological evidence of scurvy can be seen on plain radiographs of long bones, which are typically symmetrical and bilateral [4,5]:
MRI can detect early changes in scurvy. The commonest finding is diffuse multifocal decreased T1- weighted signal and increased T2-weighted signal within the bone marrow; with the metaphysis being the most affected. [6]
Outcome
The child was diagnosed with scurvy and was commenced on vitamin c replacement. His symptoms fully resolved. Overall, scurvy has an excellent prognosis.
Take-Home Message
Scurvy should be considered as a rare cause for limb and joint pain, particularly in high-risk children. It is important for radiologists to be aware of imaging findings found in scurvy and to appreciate the clinical context.
Vitamin C deficiency (Scurvy)
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Based on the provided bilateral lower extremity X-ray and knee MRI images, the following main features are noted:
Combining the patient’s condition (a 12-year-old male with symmetrical swelling of both lower limbs, recurrent knee pain, gum bleeding, and bruising) and the imaging findings suggestive of malnutrition-related bone changes and hemorrhagic signs, the following differential diagnoses are considered:
Taking into account the patient’s dietary history, gum bleeding, recurrent bruising, and the aforementioned metaphyseal bone changes and subperiosteal hemorrhage on imaging, the most likely diagnosis is scurvy (Scurvy).
Once symptoms improve and vitamin C supplementation takes effect, gradually introduce lower limb functional exercises focusing on protecting bones and joints. Refer to the FITT-VP principles:
Important note: During the early recovery phase, avoid strenuous running, jumping, or heavy weight-bearing activities to prevent provoking additional bleeding or bone injury.
This report is a reference analysis based on limited information and cannot replace in-person consultations or professional medical advice. All treatment and rehabilitation plans should be tailored to the patient’s actual condition and conducted under the guidance of qualified healthcare professionals.
Vitamin C deficiency (Scurvy)
