Burwell R Geoffrey, Aujla Ranjit K, Grevitt Michael P, Randell Tabitha L, Dangerfield Peter H, Cole Ashley A, Kirby Alanah S, Polak Frances J, Pratt Roland K, Webb John K, Moulton Alan
Centre for Spinal Studies and Surgery, Nottingham University Hospitals Trust, Nottingham, UK.
Stud Health Technol Inform. 2012;176:188-94.
In girls with adolescent idiopathic scoliosis (AIS) the finding of abnormal extra-spinal bilateral skeletal length asymmetries in upper limbs, periapical ribs, and ilia begs the question whether these bilateral asymmetries are connected in some way with pathogenesis.
We investigated upper arm length (UAL) asymmetries in two groups of right-handed girls aged 11-18 years with right thoracic adolescent idiopathic scoliosis (RT-AIS, n=95) from preoperative and screening referrals (mean Cobb angle 46°) and healthy controls (n=240). Right and left UAL were measured with a Harpenden anthropometer of the Holtain equipment, Asymmetry was calculated as UAL difference, right minus left, in mm. Repeatability of the measurements was assessed as technical error of the measurement and coefficient of reliability.
In girls with RT-AIS, UAL asymmetry was greater than in healthy girls, regressed negatively with age and correlated significantly with Cobb angle and apical vertebral rotation. In healthy girls, UAL asymmetry was unrelated to age. Plotted against years after estimated menarcheal age, UAL asymmetry decreased significantly for girls with RT-AIS but not for healthy girls.
The apparent transience of the abnormal UAL asymmetry suggests it is not secondary to spinal deformity but pathogenetically associated with it. We suggest two hypotheses to account for these changes: (1) a transient asymmetry process with growth velocity; and (2) in the light of subsequent research, early skeletal overgrowth with catch-down growth affecting right but not left upper arm. The relation of the upper arm length asymmetry to the increased length of periapical left ribs reported for RT-AIS is unknown. Right upper arm length may provide a more simple model than arm span, for estimating linear skeletal overgrowth of girls with RT-AIS.
在青少年特发性脊柱侧凸（AIS）女孩中，上肢、根尖肋骨和髂骨出现异常的脊柱外双侧骨骼长度不对称，这引发了一个问题，即这些双侧不对称是否在某种程度上与发病机制有关。
我们调查了两组年龄在11 - 18岁的右利手女孩的上臂长度（UAL）不对称情况，一组是术前和筛查转诊的右胸青少年特发性脊柱侧凸（RT - AIS，n = 95）患者（平均Cobb角46°），另一组是健康对照者（n = 240）。使用霍尔坦设备的哈彭登人体测量仪测量左右UAL，不对称性以UAL差值（右减左，单位为mm）计算。测量的重复性通过测量技术误差和可靠性系数进行评估。
在RT - AIS女孩中，UAL不对称性大于健康女孩，与年龄呈负相关，且与Cobb角和顶椎旋转显著相关。在健康女孩中，UAL不对称性与年龄无关。以预计初潮年龄后的年份为横坐标绘制图表，RT - AIS女孩的UAL不对称性显著下降，而健康女孩则没有。
UAL异常不对称的明显短暂性表明它并非继发于脊柱畸形，而是在发病机制上与之相关。我们提出两个假说来解释这些变化：（1）与生长速度相关的短暂不对称过程；（2）根据后续研究，早期骨骼过度生长并伴有追赶性生长，影响右侧而非左侧上臂。RT - AIS患者根尖左侧肋骨长度增加与上臂长度不对称的关系尚不清楚。右上臂长度可能比臂展提供一个更简单的模型，用于估计RT - AIS女孩的线性骨骼过度生长情况。
