The patient was a 49-year-old woman with a history of: degenerative L5-S1 disk disease, who underwent total disk replacement with a prosthesis, and secondary facet syndrome. She was seen in the clinic due to back pain, which was secondary to mechanical disk disease. General analysis showed calcium 9.8mg/dl (8.5–10.5), phosphorus 3.2mg/dl (2.5–4.8), alkaline phosphatase 102U/l (35–104), intact PTH 22pg/ml (12–65) and vitamin D (25-0H) 57.50ng/ml (≥30).

A routine X-ray of the lumbar spine (Fig. 1) showed many small, well-defined, homogeneous, circular areas of increased bone density in the vertebral bodies and throughout the axial skeleton we observed similar foci, which therefore led us to ask for AP pelvic X-rays (Fig. 2) and a CT of the pelvis and lumbar spine (Figs. 3 and 4), which showed radiodense round or oval lesions on the femoral head, neck, and the trochanteric regions, with the presence of small areas of increased density in the pelvis and the vertebral bodies suggesting, as a first diagnosis, osteopoikilosis. No soft tissue component or fractures in the areas of the cortex were seen, nor was the presence of periosteal reactions observed.

Fig. 1.

X-ray of the lumbar spine showing numerous small, well-defined, homogeneous, circular, increased radiodensity foci in the vertebral bodies.

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Fig. 2.

X-ray of pelvis: showing round or oval radiodense lesions on the head, neck and intertrochanteric region of both femurs and pelvis.

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Fig. 3.

CT pelvis: small hyperdense areas in the sacrum and iliac bones, both <10mm without signs of malignancy.

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Fig. 4.

CT lumbar spine: small density areas of increased density in the vertebral bodies.

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To rule out other processes, a bone biopsy of the iliac crest bone was performed which was normal, with large, wide, trabeculae, and connecting to each other. X-ray images highly indicative of osteopoikilosis and the normality of laboratory investigations, including bone biopsy, led us to the diagnosis of osteopoikilosis.

Osteopoikilosis is a rare bone disease,2 with a prevalence of about one in 50000 patients3,4 consisting of a bone dysplasia with multiple radiodense foci located in the trabecular bone.5,6 It is more common in men and familial cases have been described, with autosomal dominant inheritance.5,6 It is described as a genetic mutation in the LEMD3 gene.4,7 It is clinically asymptomatic. The most common locations of occurrence seen are the carpal and metacarpal phalanges, the phalanges of the foot, metatarsals, tarsus, pelvis, femur, sacrum, humerus, and tibia. The involvement of the ribs, clavicles, spine, and skull is uncommon.5,8,9 Sometimes it may be associated with papular, yellowish or white, round or oval skin lesions, located on the lower back, buttocks, arms, and thighs, with certain symmetry (dermatolenticular disseminated fibrosis), something called the Buschke–Ollendorff syndrome or osteodermatopoikilosis.5 The diagnosis is radiological because the image is very indicative, characterized by foci of sclerosis, rarely over 10mm, without affecting cortical bone. Bone scans shows no pathological data, which is very useful in making the differential diagnosis with other osteocondensing lesions.5,9 Histologically, there is an increase in the number and thickness of the trabeculae of the spongy bone5,6,8 as in our case.

The differential diagnosis includes osteoblastic bone metastases, mastocytosis, tuberous sclerosis, striated osteopathy, melorheostosis, osteopetrosis, sclerosteosis, Erdheim–Chester disease or fluorosis.7,10

The authors declare no conflicts of interest.