Tallroth Kaj, Harilainen Arsi, Kerttula Liisa, Sayed Raafat
Department of Radiology, ORTON Orthopaedic Hospital, Helsinki, Finland.
Arch Orthop Trauma Surg. 2008 Jun;128(6):555-60. doi: 10.1007/s00402-007-0502-9. Epub 2007 Nov 20.
Osteoarthritis (OA) of the ankle with an unknown etiology (primary OA) is rare, whereas a secondary OA due to a known cause is not uncommon. OA of the knee can, when it progresses, change the alignment of the whole extremity including the ankle joint. Since we had observed in patients coming for OA knee surgery coexisting OA in the ankle joint, our objective of this study was to assess the prevalence of abnormal alignment and degenerative changes in the ankle joint and to determine if degenerative changes in the knee and ankle correlated. These aims were assessed retrospectively, utilizing mechanical axis (MA) radiographs of subjects with knee OA prior to surgery.
This retrospective study consisted of 104 patients who had undergone surgery of the knee due to OA. A musculoskeletal radiologist and an orthopedic surgeon reviewed in consensus the preoperative and postoperative MA radiographs. We analyzed and measured the tibiofemoral (TF) angle, the mediolateral tibial translation, the deviation of the MA, the tilt of the talocrural joint and the degree of OA in the knee and ankle.
The severity of OA of the TF joint correlated with the preoperative TF translation and moderately with the deviation of the MA and abnormal TF angle. Of the 104 patients, 30 showed coexisting OA of the ankle: the greater the tilt in the ankle, the more degenerative were the changes in the joint. The MA was corrected with surgery from a mean preoperative 5.4 degrees varus to a postoperative mean 1.2 degrees valgus, and the ankle tilt was changed significantly at the same time.
Ankle OA and tilt were not uncommon in our patients with knee OA. The assumption that associations may exist between knee and ankle OA and joint malalignment was confirmed.
病因不明的踝关节骨关节炎（原发性骨关节炎）较为罕见，而由已知病因引起的继发性骨关节炎并不少见。膝关节骨关节炎进展时，可改变包括踝关节在内的整个下肢的力线。由于我们在接受膝关节骨关节炎手术的患者中观察到踝关节同时存在骨关节炎，本研究的目的是评估踝关节异常力线和退变改变的患病率，并确定膝关节和踝关节的退变改变是否相关。这些目标通过回顾性分析膝关节骨关节炎患者术前的机械轴位（MA）X线片进行评估。
这项回顾性研究包括104例因骨关节炎接受膝关节手术的患者。一名肌肉骨骼放射科医生和一名骨科医生共同回顾了术前和术后的MA X线片。我们分析并测量了胫股（TF）角、胫骨内外侧平移、MA偏差、距小腿关节倾斜度以及膝关节和踝关节的骨关节炎程度。
TF关节骨关节炎的严重程度与术前TF平移相关，与MA偏差和异常TF角中度相关。在104例患者中，30例显示踝关节同时存在骨关节炎：踝关节倾斜度越大，关节退变改变越严重。手术使MA从术前平均内翻5.4度矫正为术后平均外翻1.2度，同时踝关节倾斜度也发生了显著变化。
在我们的膝关节骨关节炎患者中，踝关节骨关节炎和倾斜并不少见。膝关节和踝关节骨关节炎以及关节排列不齐之间可能存在关联这一假设得到了证实。
