Pituitary stalk interruption syndrome (PSIS) is a newly discovered rare endocrinological syndrome characterized by structrual defect of pituitary and multiple deficiencies of a series of hypothalamic hormones, and thus leading to a cluster of clinical symptoms. This review will illustrate the genetic pathogenic factors influence on embryonic development, and briefly introduce the current studies of Whole-Exome Sequencing on PSIS.

Objective:To compare treatment effect of the new multi-dimensional cross locking plate-II (MDC-LP-II) and locking compression plate (LCP) as additional plates in the treatment of nonunion after intramedullary nailing treatment of subtrochanteric fractures.Methods:A retrospective analysis was performed on 23 patients with nonunion after subtrochanteric fractures treated with intramedullary nails from January 2019 to January 2021. According to the type of additional plate, it was divided into MDC-LP-II group and LCP group. There were 12 patients in MDC-LP-II group, including 10 males and 2 females, with an age of 36.83±12.61 years, a body mass index (BMI) of 25.09±2.37 kg/m 2, the time from the last operation to this treatment was 12.25±2.93 months, the number of previous operations was 1.33±0.65, 5 cases of hypertrophic nonunion, 7 cases of atrophic nonunion, and the length of bone nonunion defect was 1.19±0.78 cm. In the LCP group, there were 11 cases, 9 males and 2 females, aged 30.55±8.85 years, BMI was 26.74±5.05 kg/m 2, a time of 12.82±4.40 months after the last operation, the number of previous operations was 1.36±0.96, 5 cases of hypertrophic nonunion, 6 cases of atrophic nonunion, and the length of bone nonunion defect was 1.20±0.57 cm. The incision length, additional plate length, number of screws, number of bicortical screws, intraoperative blood loss, blood transfusion, healing time of nonunion, Harris hip score, lower extremity functional scale (LEFS) and the medical outcomes study item short from health survey-36 (SF-36) were compared between the two groups. Results:All 23 patients were followed up. The follow-up time of MDC-LP-II group was 14.17±2.55 months, and that of LCP group was 14.45±3.75 months, with no significant difference ( t=0.22, P=0.834). In MDC-LP-II group, the incision length was 7.25±2.01 cm, the plate length was 9.25±0.62 cm, the number of screws was 7.17±0.94, the number of bicortical screws was 7.17±0.94, the intraoperative blood loss was 279.17±169.84 ml, and the blood transfusion was 166.67±187.05 ml. In LCP group, the incision length was 15.45±4.72 cm, the plate length was 15.51±2.38 cm, the number of screws was 5.09±0.95, the number of bicortical screws was 1.82±1.72, the intraoperative blood loss was 481.82±227.24 ml, and the blood transfusion was 685.45±299.95 ml. There were significant differences in incision length ( P<0.05), plate length ( P<0.05), number of screws ( P<0.05), number of bicortical screws ( P<0.05), intraoperative blood loss ( P<0.05), and blood transfusion volume ( P<0.05) between the two groups. The fracture healing rate was 100% in MDC-LP-II group and 64% in LCP group at 6 months after operation, and the difference was statistically significant ( P<0.05). At 12 months after operation, the healing rate of LCP group was 91%, and the difference was not statistically significant ( P=0.478). The Harris score 92.83±8.04 and LEFS 74.92±6.68 at the last follow-up in MDC-LP-II group and the Harris hip score 83.36±9.89 and LEFS 66.27±7.68 at the last follow-up in LCP group were significantly different between the two groups ( P<0.05). In terms of SF-36, scores of physical function, physical pain, general health status, vital vitality and mental health of MDC-LP-II group were higher than those of LCP group. No complications related to the use of MDC-LP-II or LCP fixation were observed in both groups. Conclusion:On the basis of preserving the original intramedullary nail, MDC-LP-II compared with LCP as additional plates in the rebuilding of nonunion after intramedullary nailing treatment of subtrochanteric fractures, it can effectively enhance the stability of the broken ends in a much smaller operating range, reduce the surgical trauma, protect the local blood supply and accelerate the healing of the broken end of the fracture. The patients who received MDC-LP-II treatment had better lower limb function recovery and quality of life.

Objective:To compare the anti-rotation stability between different modes of augmentative plating for femoral shaft nonunion after intramedullary nailing.Methods:Fifteen artificial synthetic femurs were used to create models of femoral shaft nonunion with rotational instability after intramedullary nailing. They were randomly divided into 3 groups ( n=5). Control group 1 was fixated with lateral locking compression plate (LCP), control group 2 with anterior LCP, and the experimental group with anterior multi-dimensional cross locking plate (MDC-LP). After fixation, all the groups were subjected to a torsional loading test, with the torsional loading starting from 0 N·m till 10 N·m and a loading speed of 6°/min. The 3 model groups were compared in terms of torsional angle and stiffness. Results:Under the torsion loading, the torsional angles for control group 1, control group 2 and the experimental group were 9.69°±0.34°, 7.15°±0.20° and 1.59°±0.02°, respectively, showing significant differences ( P=0.002); the torsional angle for the experi mental group was significantly smaller than that for control group 1 ( P<0.05). The torsion stiffness for control group 1, control group 2 and the experimental group was respectively 1.02 N·m/° ±0.04 N·m/°, 1.39 N·m/° ± 0.04 N·m/° and 6.16 N·m/° ± 0.06 N·m/°, showing significant differences ( P=14 886.140, P<0.001); there was a significant difference between any 2 groups ( P< 0.05). Conclusions:In the management of femoral shaft nonunion after intramedullary nailing, anterior augmentative plating can provide better anti-torsional stability than lateral augmentative plating, and MDC-LP can also provide better anti-torsional stability than a conventional LCP because it leads to bicortical fixation of the screws.