Objective To provide accurate bone tunnel positioning reference for clinical individual anterior cruciate ligament (ACL) reconstruction by three-dimensional (3D) reconstruction of femoral and tibial original footprint of ACL.Methods Forty volunteers were selected for this study,including 20 males and 20 females,and aged 18 to 35 years old.3D CT scanning images of knee data were obtained.3D bone models of knee and footprint of ACL were reconstructed.On the 3D reconstruction models,the shape and position of original footprint of ACL were displayed.Statistical significance was compared for their difference.Results Femoral original footprint of ACL,long axis of footprint,distances to the distal margin of the articular cartilage (DDCM),distances to the posterior margin of the articular cartilage (DPCM),double bundle center distance,and tibial original footprint short axis of ACL were significantly different between genders (P ＜ 0.05).However,no significant difference was found between genders for tibial original footprint long axis of ACL (P ＞ 0.05).Conclusions The insertion mark shape and nature position of footprint of ACL could be observed by 3D reconstruction using CT scan images.

Objective: To analyze the clinical characteristics and treatment of pseudohypoparathyroidism(PHP) in children and to increase clinicians′understanding of this disorder. Methods: From January 2008 to November 2018, a total of 14 PHP patients at our hospital were retrospectively analyzed, as regarding the clinical manifestation, laboratory examination and imaging data.The patients were further divided into two groups according to onset age: group A(under 1 year) and group B(over or equal to 1 year). The laboratory findings were compared between the two groups. Results: Of the 14 patients(10 boys and 4 girls), the median age of onset was 12 years(range: 1 day to 16 years). Epilepsy is one of the most common manifestations of PHP.Laboratory findings include hypocalcemia(1.06-2.18mmol/L), hyperphosphatemia(2.1-3.5 mmol/L), and elevated concentrations of PTH(105.6-733.0 pg/ml). PTH levels were significantly lower in the group A than in group B(Z=2.07, P=0.042). Five patients were found to have calcifications in bilateral basal ganglia and cerebral parenchyma by head CT.All the patients were improved after treatment, which included calcium gluconate injection to control tetany, calcium supplement combined with vitamin D and/or calcitriol orally. Conclusion For children who presented frequent hypocalcemia tetany and calcifications in head CT, serum calcium, phosphorus, PTH levels should be further investigated to make a correct diagnosis.Calcium supplement combined with vitamin D or its metabolites is an effective therapy for PHP children.