A comparative study on imaging parameters of Chevron combined with Akin osteotomy and Scarf combined with Akin osteotomy for the correction of hallux valgus in patients at different ages

Objective:To study the imaging parameters of Chevron combined with Akin and Scarf combined with Akin for the correction of hallux valgus in patients of different ages.Methods:Eighty patients(152 feet)with hallux valgus who underwent Chevron combined with Akin and Scarf combined with Akin in our hospital were randomly selected.The patients were divided into young and middle-aged groups.Measure the hallux valgus angles(HVA),distal metatarsal articular angle(DMAA)and intermetatarsal angles(IMA)with professional X-ray measurement software and then reseach the effect of two the operation methods.Results:Young group:Chevron combined with Akin and Scarf combined with Akin significantly improved HVA and IMA,the difference had statistical significance(P<0.05),but the improvement effect of the two groups was similar,and the difference had no statistical significance(P>0.05).The improvement effect of the two groups on DMAA in young patients was not significant,and the difference had no statistical significance(P>0.05);Middle-aged group:Chevron combined with Akin and Scarf combined with Akin also significantly improved HVA and IMA(P<0.05),but the improvement effect of the two groups was similar,and the difference had no statistical significance(P>0.05).Chevron combined with Akin significantly improved DMAA in middle-aged and elderly patients,and the difference had statistical significance(P<0.05).Scarf combined with Akin did not significantly improve DMAA in middle-aged and elderly patients,and the difference had no statistical significance(P<0.05).Conclusion:Both Chevron combined with Akin and Scarf combined with Akin are effective and widely used.Chevron combined with Akin was able to improve DMAA in middle-aged and elderly patients.Therefore,Chevron combined with Akin is recommended for middle-aged and elderly patients with hallux valgus.

Compressive Biomechanics of the Reptilian Intervertebral Joint

This study compared the pre-sacral intervertebral joints of the American alligator(Alligator mississippiensis)with those from specimens of Varanus.These two taxa were chosen because they have similar number of pre-sacral vertebrae and similar body weights;however,Varanus can move bipedally and has diarthrotic intervertebral joints,whereas Alligator has intervertebral discs and cannot move bipedally.This study consisted of three objectives:(1)to document the anatomy of the intervertebral joint,(2)to quantify the compressive biomechanics of the intervertebral joints and explore which features contributed to compression resistance,and(3)to quantify the impact of compression on the intervertebral foramen and spinal nerves in these two taxa.The experimental results revealed that the diarthrotic intervertebral joints of Varanus were significantly(4x)stiffer than the intervertebral disc of Alligator,and that a significant component of this increased stiffness arose from the facet joints.Compressing the intervertebral joints of the two taxa caused a reduction in foraminal area,but the magnitude of this reduction was not significantly different.We hypothesize that the main factor preventing spinal nerve impingement in Varanus during gravitational compression is the relatively small size of the spinal ganglion/nerve relative to the foraminal area.