Investigation of causal relationships between cortical structure and osteoporosis using two-sample Mendelian randomization.

The mutual interaction between bone characteristics and brain had been reported previously, yet whether the cortical structure has any relevance to osteoporosis is questionable. Therefore, we applied a two-sample bidirectional Mendelian randomization analysis to investigate this relationship. We utilized the bone mineral density measurements of femoral neck (n = 32,735) and lumbar spine (n = 28,498) and data on osteoporosis (7300 cases and 358,014 controls). The global surficial area and thickness and 34 specific functional regions of 51,665 patients were screened by magnetic resonance imaging. For the primary estimate, we utilized the inverse-variance weighted method. The Mendelian randomization-Egger intercept test, MR-PRESSO, Cochran's Q test, and "leave-one-out" sensitivity analysis were conducted to assess heterogeneity and pleiotropy. We observed suggestive associations between decreased thickness in the precentral region (OR = 0.034, P = 0.003) and increased chance of having osteoporosis. The results also revealed suggestive causality of decreased bone mineral density in femoral neck to declined total cortical surface area (ß = 1400.230 mm2, P = 0.003), as well as the vulnerability to osteoporosis and reduced thickness in the Parstriangularis region (ß = -0.006 mm, P = 0.002). Our study supports that the brain and skeleton exhibit bidirectional crosstalk, indicating the presence of a mutual brain-bone interaction.

[Descending branch of anterior lateral malleolar artery based anterograde island flaps for reconstruction of foot and ankle defects].

OBJECTIVE: To explore surgical method and clinical effects of descending branch of the anterior lateral malleolar artery based anterograde island flap for repairing foot and ankle wounds. METHODS: Nine patients with skin defects of foot and ankle repaired by descending branch of the anterior lateral malleolar artery based anterograde island flap were studied from June 2015 to January 2017, including 6 males and 3 females aged from 32 to 63 years old. The wound were located on foot and ankle and associated with exposure of bone, tendon, blood vessels or nerves. The surface of wound located on foot in 6 patients, and 3 patients in ankle joint. The area of defect ranged from 1.5 cm×2.0 cm to 6.0 cm×13.0 cm, and the area of flap ranged from 2.0 cm×3.0 cm to 7.0 cm×15.0 cm. The donor site was skin grafted with split-thickness skin from abdomen. Appearance, texture, condition of donor site of island flaps after operation were observed, satisfied degree of clinical effects were evaluated by ZHANG Hao's evaluation, and AOFAS score were used to evaluate function. RESULTS: Circulations of flaps in 9 cases were stable without blockage, and healed well at 2 weeks after operation. All patients were followed up from 2 to 18 months with an average of(8.0±2.3) months. All flap were survived at stage I, pedicles looked smooth and tidy, no cat-ear formed, the texture of flap was soft with satisfied appearance, the color was near to surrounding skin. The surface of wound were tidy after skin graft of donor sites without scar hypertrophy. Nine patients got satisfied results according to ZHANG Hao's evaluation, and AOFAS score was excellent. CONCLUSIONS: Descending branch of the anterior lateral malleolar artery based anterograde island flap for repairing foot and ankle wounds, which has advantages of protect main vessel, thin flap, is a simple and effective method.

[Percutaneous fixation for the treatment of un-displaced scaphoid fractures with herbert cannulated screws through volar approach].

OBJECTIVE: To summarize the experience of percutaneous fixation of scaphoid fractures with Herbert screws through volar approach, and provide a reliable and efficient treatment method for scaphoid fractures. METHODS: From April 2008 to September 2012,15 patients with scaphoid fractures were treated by percutaneous fixation with Herbert cannulated screws through volar approach including 14 males and 1 female with an average age of 35 years ranging from 25 to 45 years old. Among them, 10 cases were on left side and 5 cases were on right side. Durations from injury to operation ranged from 3 to 10 days with an average of 5 days. All these cases were identified as B2 type according to the Herbert classification based on X-ray and CT scan. In order to assess the function of wrist, all patients were calculated according to Krimmer's score postoperatively. RESULTS: The follow-up period were from 5 to 18 months with an average of 10 months. At 3 months after operation,X-ray was re-checked every month. All the patients achieved bone union with a mean time of 10 weeks (ranged from 7 to 14 weeks) postoperatively. According to Krimmer's score, 14 cases gained 100 scores as perfect and one case got 90 scores as good. The small volar incision of all patients were union at the first period. No operation complications such as infection and nonunion occurred. CONCLUSION: Percutaneous fixation with Herbert cannulated screws through volar approach is a reliable and efficient treatment method for scaphoid fractures with small invasion, high bone union rate, and fewer complications.