2.1 History of present illness
An 18-year-old woman who suffered from left lower limb deformity and
thigh pain for > 10 years was admitted to our center.
Physical examination revealed lower limb discrepancy (−2.5 cm in left
leg), limping gait, left groin area tenderness, and restricted range of
motion in the left hip. Neither café-au-lait spots nor sexual precocity
was found. X-ray and computed tomography (CT) imaging showed severe coxa
varus in the left hip (femoral neck-shaft angle = 60°), varus alignment
of the femur, and shepherd cane deformity (Figure 1A). Single-photon
emission computed tomography (SPECT) demonstrated multiple osteolytic
lesions located in craniofacial bone, left femur and left tibia (Figure
1B). Preoperative electrocardiography and chest radiography showed no
positive findings. Polyostotic fibrous dysplasia was considered as the
primary diagnosis. For lower limb deformity correction, proximal femur
osteotomy and internal fixation of the left femur were performed after
detailed preoperative planning (Figure 2A). Total operation time was 117
min and intraoperative blood loss was 800 mL. Postoperative radiography
showed significant improvement of coxa varus and correction of the
shepherd’s crook deformity (femoral neck-shaft angle = 104°) (Figure
2B). Total fluid replacement volume was 1850 ml in the first 24 h after
surgery with restricted fluid infusion rate (40–60 drops /min).
Genetic testing of the
pathological bone tissue from the proximal left femur revealed mutation
of c.601C>T (Figure 3). The patient was finally diagnosed
with MAS according to previous studies5, 6. However,
on the morning of postoperative day 2, the patient suddenly complained
of chest pain, palpitation, and dyspnea without any known cause.