Quadriceps contracture (QC) is reported in dogs mainly as a complication of trauma or parasitic infection. QC causes progressive hind limb deviation, muscular hypotrophy and degenerative joint disease and, in puppies, bone hypoplasia. The aim of this clinical case series is to describe the radiographic and computed tomographic (CT) changes in hind limb ossification centres in thirteen 55 to 57-days-old Doberman Pinscher related littermates induced by QC after repeated intramuscular injections. The presence, size, and shape of ossification centres of affected and unaffected hind limbs were compared. Affected limbs were hyperextended and externally rotated, with genu recurvatum and proximo-medial patellar luxation. QC had no influence on the time of appearance of ossification centres however, it was associated with femoral head flattening, hip subluxation, flattening of the femoral distal epiphysis. The tibial plateau was tilted caudoproximally-craniodistally and wedged into the growth plate. Thirty-two out of fifty-five ossification centres (including diaphyseal and epiphyseal centres, such as femoral head and tibial plateau) were significantly smaller in affected limbs (p < 0.05). Lack of weight-bearing could account for the smaller size of ossification centres in affected tarsi and metatarsi. Progressive limb hyperextension and external rotation might have induced gradual loading withdrawal on the medial aspect of the foot justifying the reduced size observed only for the medial ossification centres of the digits of affected limbs. To the best of our knowledge, this is the first study describing CT findings of hind limb ossification centre changes in puppies with QC contracture.

据报道，狗股四头肌挛缩症（QC）主要是外伤或寄生虫感染的并发症。QC会导致进行性后肢偏斜，肌肉萎缩和关节退行性疾病，以及幼犬的骨骼发育不全。本临床病例系列的目的是描述在反复肌肉内注射后，由QC诱导的13至55至57天大的与Doberman Pinscher相关的同窝出生的后肢骨化中心的射线照相和计算机断层扫描（CT）变化。比较受影响和未受影响的后肢骨化中心的存在，大小和形状。受累肢体过度伸展并向外旋转，并弯曲膝和近中pa骨脱位。QC对骨化中心的出现时间没有影响，但是它与股骨头扁平，髋关节半脱位，股骨远端骨physi扁平化有关。胫骨平台被颅顶近颅倾斜，并楔入生长板。在患肢中，有55个骨化中心中的32个（包括骨干和骨phy中心，例如股骨头和胫骨平台）明显较小（p <0.05）。负重的缺乏可能导致受影响的骨和meta骨的骨化中心变小。进行性肢体过度伸展和外旋可能导致脚内侧逐渐逐渐减负，证明只有在患肢的手指内侧骨化中心才观察到大小减小。据我们所知，这是第一项描述QC挛缩幼犬后肢骨化中心改变的CT表现的研究。