Tower S S, Beals R K, Duwelius P J
Division of Orthopedics and Rehabilitation, Oregon Health Sciences University, Portland.
J Orthop Trauma. 1993;7(6):552-7. doi: 10.1097/00005131-199312000-00011.
The Resonant Frequency (RF) of the tibia is proportional to its stiffness. As a fractured tibia heals, its RF should increase. The RF was serially determined in 74 fractured tibias (205 examinations). These were subdivided by fracture location and fixation. Fast Fourier transform software generates the RF from data obtained with an instrumented impactor and accelerometer. The RF was normalized by expressing it as a ratio of the intact tibia. This ratio is called the tibial stiffness index (TSI). A 20 point tibial fracture score (TFS) quantitated the clinical and radiographic signs of healing. For each group the paired TSI and TFS were compared by regression analysis. Except for those fractures limited to the proximal fourth of the tibia, the TSI was found to correlate significantly (p = 0.0001) with the TFS. Fractures without fixation and those with unlocked, unreamed tibial nails showed very significant correlation of TSI with TFS (p = 0.0001). RF analysis was not useful in fractures with locked or reamed tibial nails. Examination of tibia with external fixation showed significant correlation (p = 0.02) of the TSI with the TFS.
胫骨的共振频率（RF）与其刚度成正比。随着胫骨骨折愈合，其RF应增加。对74例胫骨骨折患者（共进行205次检查）连续测定RF。这些患者根据骨折部位和固定方式进行了细分。快速傅里叶变换软件根据用仪器化冲击器和加速度计获得的数据生成RF。通过将RF表示为完整胫骨的比率进行归一化处理。该比率称为胫骨刚度指数（TSI）。一个20分的胫骨骨折评分（TFS）对愈合的临床和影像学表现进行量化。对每组进行配对TSI和TFS的回归分析。除了那些仅限于胫骨近端四分之一的骨折外，发现TSI与TFS显著相关（p = 0.0001）。未固定的骨折以及使用未锁定、未扩髓胫骨钉的骨折显示TSI与TFS有非常显著的相关性（p = 0.0001）。RF分析对使用锁定或扩髓胫骨钉的骨折无用。对采用外固定的胫骨进行检查显示TSI与TFS有显著相关性（p = 0.02）。
