The Journal of bone and joint surgery. American volume
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J Bone Joint Surg Am · Oct 2009
The hip-knee-ankle angle in children: reference values based on a full-length standing radiograph.
It is well recognized that the alignment of the lower limb changes during early childhood. The hip-knee-ankle angle is often referred to as the mechanical femoral-tibial angle and is measured on a full-length radiograph of the lower extremity. While several authors have independently reported consistent reference values for the hip-knee-ankle angle in adults, such values have not been well documented for children. The purpose of our study was to establish reference values for the hip-knee-ankle angle and assess the relationship between it and the anatomic femoral-tibial angle in children. ⋯ In our study sample, reference values for the hip-knee-ankle angle in children older than seven years of age approached those reported for adults in North America. Although this angle and the anatomic femoral-tibial angle in children younger than seven were distinct from those reported for the adult population, the difference between the two angular measurements remained essentially unaffected. The use of age-specific reference values for both the hip-knee-ankle and the anatomic femoral-tibial angle is recommended for children younger than seven years old.
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J Bone Joint Surg Am · Oct 2009
Comparative StudySurgical treatment of main thoracic scoliosis with thoracoscopic anterior instrumentation. Surgical technique.
The surgical outcomes in patients with scoliosis at two years following anterior thoracoscopic spinal instrumentation and fusion have been reported. The purpose of this study was to evaluate the results at five years. ⋯ Thoracoscopic anterior instrumentation for main thoracic idiopathic scoliosis results in five-year outcomes comparable with those reported previously for open anterior and posterior techniques. The radiographic findings, pulmonary function, and clinical measures remain stable between the two and five-year follow-up time points. Thoracoscopic instrumentation provides a viable alternative to treat spinal deformity; however, the risks of pseudarthrosis, hardware failure, and surgical revision should be considered along with the advantages of limited muscular dissection and improved scar appearance.
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J Bone Joint Surg Am · Oct 2009
Comparative StudyCervical disc arthroplasty compared with arthrodesis for the treatment of myelopathy. Surgical technique.
Although there have been case reports describing the use of cervical disc arthroplasty for the treatment of myelopathy, there is a concern that motion preservation may maintain microtrauma to the spinal cord, negatively affecting the clinical results. As we are not aware of any studies on the use of arthroplasty in this scenario, we performed a cross-sectional analysis of two large, prospective, randomized multicenter trials to evaluate the efficacy of cervical disc arthroplasty for the treatment of myelopathy. ⋯ We found that patients in both the arthroplasty and arthrodesis groups had improvement following surgery; furthermore, improvement was similar between the groups, with no worsening of myelopathy in the arthroplasty group. While the findings at two years postoperatively suggest that arthroplasty is equivalent to arthrodesis for the treatment of cervical myelopathy for a single-level abnormality localized to the disc space, the present study did not evaluate the treatment of retrovertebral compression as occurs in association with ossification of the posterior longitudinal ligament, and we cannot comment on the treatment of this condition.
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J Bone Joint Surg Am · Oct 2009
Comparative StudyTreatment of scaphoid waist nonunions with an avascular proximal pole and carpal collapse. Surgical technique.
Surgically, it is difficult to achieve union of a scaphoid nonunion that is associated with osteonecrosis of the proximal pole, and those with carpal collapse are especially difficult to treat. A variety of vascularized bone grafts can be used. The purpose of this study was to compare the effectiveness of two types of vascularized bone graft -- a distal radial pedicle graft and a free vascularized medial femoral condyle graft -- in the treatment of scaphoid waist nonunions associated with proximal pole osteonecrosis and carpal collapse. ⋯ A vascularized interposition graft from the medial femoral condyle is the recommended vascularized bone graft for the surgical treatment of scaphoid waist nonunion with avascularity of the proximal pole and carpal collapse.
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J Bone Joint Surg Am · Oct 2009
Biomechanical consequences of a tear of the posterior root of the medial meniscus. Surgical technique.
Tears of the posterior root of the medial meniscus are becoming increasingly recognized. They can cause rapidly progressive arthritis, yet their biomechanical effects are not understood. The goal of this study was to determine the effects of posterior root tears of the medial meniscus and their repairs on tibiofemoral joint contact pressure and kinematics. ⋯ This study demonstrated significant changes in contact pressure and knee joint kinematics due to a posterior root tear of the medial meniscus. Root repair was successful in restoring joint biomechanics to within normal conditions.