ABSTRACT
Objective:To analyze the risk factors of avascular necrosis (AVN) after closed reduction and spcia casting in treating developmental dysplaisa of the hip (DDH).Methods:The patients with DDH who received closed reduction in our department from January 2016 to December 2017 were retrospectively reviewed. The inclusion criteria included aged at reduction ≥6 months, achieving successful reduction, having complete data with more than 2 years follow-up. A total of 48 cases with 54 hips were included in the present study. Among them, there were 2 males and 46 females, 41 unilateral hips and 13 bilateral hips. The mean age at closed reduction was 16.4±3.8 months (range 6-24 months). The mean follow-up duration was 2.9±1.8 years (range 2.3-4.1 years). Closed reduction was conducted under general anesthesia followed with a spcia cast immobilization. The abduction angle of the cast was recorded. The stability of reduction was evaluated by Ramsey safety zone. The maximum abduction and re-dislocation abduction were recorded. The quality of reduction was evaluated by the medial gap and femoral head coverage on intraoperative arthrography and post-reduction MRI. AVN was diagnosed according to Salter criteria. The risk factors of AVN were analyzed by univariate and binary logistic regression analysis.Results:AVN occurred in 12 hips (22.2%) of 54 hips. International Hip Dysplasia Institute (IHDI) grade and the difference between maximum abduction and cast abduction (Max-Cast abduction) were related to the occurrence of AVN in univariate analysis. The incidence of AVN in hips of IHDI grade 4 (42.9%, 9/21) was significantly higher than that in hips of IHDI grade 3 (9.7%, 3/31) (χ 2=6.007, P=0.018). However, the hips of IHDI grade 3 and 2 (0%, 0/2) presented a similar incidence of AVN (χ 2=0.000, P=1.000). The Max-Cast abduction was -0.7°±5.9° in the AVN group and 6.1°±7.6° in the AVN group ( t=2.125, P=0.038). Finally, IHDI grade ( OR=8.256, P=0.015) and Max-Cast abduction ( OR=0.832, P=0.047) were both independent factors of AVN in multivariate analysis. Conclusion:Most of the hips with AVN are IHDI grade 4 after closed reduction for DDH. The abduction angle in a spica cast could not be significantly related to the occurrence of AVN. However, the risk of AVN might be increased when the cast abduction is close to or beyond the maximum abduction. Safe abduction in the cast should be 5 to 10 degrees less than maximum abduction at least.
ABSTRACT
Objective:Comparing with the external fixator technique, investigate the clinical effect of fixator-assisted plating technique for treatment distal femoral valgus deformity in adolescent.Methods:A retrospective analysis of the relevant data of 22 patients (25 limbs) with acute correction of distal femoral valgus deformities from July 2015 to June 2019, according to the difference of the final fixation, they were divided two groups. The fixator-assisted plating group, including 8 patients (9 limbs), 5 boys and 3 girls, 5 left and 2 right, 1 bilateral, the physis were closed in 4 cases and opened in 4 cases, age 14.04±1.99 years (11.7-18 years). The external fixator group, including 14 patients (16 limbs), 6 boys and 8 girls, 8 left and 4 right, 2 bilateral, the physis were closed in 9 cases and opened in 5 cases, age 13.33±1.88 years (10.1-16.5 years). Measuring the mechanical axis deviation (MAD) and the mechanical lateral distal femur angle (mLDFA) in full length standing AP view X-ray of the lower limb pre and post operation. Recording the changed of limb length discrepancy (LLD) before and after surgery and the knee range of motion at 6 weeks, 3 months, 6 months and the last follow up post operation. The Kolcaba comfort status scale was used to evaluate the comfort of two groups at 2 weeks, 6 weeks, 3 months, 6 months and the last follow up. Meanwhile recorded the healing time of osteotomy sites and the complications.Results:The difference in general information between the two groups was not statistically significant. The fixator-assisted plating group followed up mean 26 months (range, 12-40 months), the healing time were 4.00±0.66 months, the mLDFA mean 73.33°±4.12° before surgery and 87.89°±1.69° after surgery and there was significant difference ( t=10.582, P<0.05). The external fixator group followed up mean 36 months (range, 22-42 months), the healing time were 4.00±0.66 months, the mLDFA mean 73.31°±3.95° before surgery and 87.31°±1.54° after surgery and there was significant difference ( t=14.118, P<0.05). The MAD were in the normal range in all patients after surgery, and there were no significant difference about healing time of the osteotomy sites and postoperative mLDFA between the two groups ( t=1.514, P=0.150; t=0.845, P=0.411). Comparing with the knee function, the fixator-assisted plating group was better at 6 weeks, 3 months, 6 months after surgery but there was no difference at the last follow up. Also, the fixator-assisted plating group felt more comfortable at 2 weeks, 6 weeks, 3 months, 6 months and there was no difference at the last follow up. All the patients with external fixator have mild pin sites infection and there were no obvious complications in patients with plate. Conclusion:The fixator-assisted plating technique can accurately correct the valgus deformity with satisfactory healing of the osteotomy in distal femoral compare with the external fixator technique, but the patients feel more comfortable and the knee joint function recovers faster and no risk of pin site infection, the clinical results was satisfactory with fewer complication.
ABSTRACT
Paraquat is a commonly used herbicide,which can cause acute poisoning due to misusage or suicide.The mortality of acute paraquat poisoning is high,the prognosis is poor,and there is no specific an-tidote for the poisoning.Most scholars believe that early blood purification is the first choice for the treatment of acute paraquat poisoning.However,there is not a unified standard about what kind of blood purification methods and the specific parameters should be taken for the different periods of paraquat poisoning.