Cemented Femoral Stem Loosening of Hip Arthroplasty: Ten-year Radiographic Analysis
WY Wong, WCS Chan, PY Chu, KW Ng, PK Hui, MK Yuen
Hong Kong J Radiol 2013;16:41-9
DOI: 10.12809/hkjr1312155
Objective: To review the radiological features of femoral stem loosening of cemented hip arthroplasty on plain radiographs and to determine their usefulness.
Methods:Between January 2002 and December 2011, 21 patients who had undergone revision of hip arthroplasty in a regional hospital in Hong Kong with cemented femoral stem loosening were retrospectively studied with respect to plain radiography indicating stem loosening. Thirty-three patients who had hip arthroplasty with cemented femoral stems between January 2004 and December 2007, without clinical suspicion of stem loosening, were included as controls. Statistical analysis was performed on the six specific radiological features: (1) osteolysis (non-linear radiolucency of >5 mm), (2) increased cement-bone interface of >2 mm, (3) radiolucent line between stem and cement at superolateral part of stem of >2 mm (subsidence), (4) radiolucent line between stem and cement in all Gruen zones of >1 mm, (5) sclerosis and thickening of bone at level of stem tip, and (6) inadequate cementation (grade C or D according to Barrack et al or cement thickness of <2 mm in any Gruen zone).
Results:Of the six radiological features, increased cement-bone interface, subsidence, and inadequate cementation were indicative of cemented femoral stem loosening, respective adjusted odds ratios being 17.4 (p = 0.003), 10.3 (p = 0.026), and 7.5 (p = 0.040). Inter-rater consistency was highest for subsidence and increased cement-bone interface (with kappa values of 0.60 and 0.56, respectively).
Conclusions:Features of increased cement-bone interface, subsidence, and inadequate cementation on plain radiographs are the strongest indicators of cemented femoral stem loosening.
中文摘要
髖關節置換術後骨水泥型股骨柄假體的鬆動：分析十年病例的放射學研究
王慧瑜、陳煥章、朱炳容、吳家榮、許炳權、袁銘強
目的：回顧髖關節置換術中水泥股骨柄鬆動在X綫平片的放射學特徵，以及探討這些特徵是否有 用。
方法：回顧研究從2002年1月至2011年12月期間於香港一所分區醫院中，21名曾進行髖關節置換術而出現水泥股骨柄鬆動的X綫平片。對照組是2004年1月至2007年12月期間進行水泥股骨柄髖關節置換 術但無股骨柄鬆動可疑性的33名病人。並按以下六項具體的放射性特徵進行統計分析：（1）骨溶解 （多於5毫米的非線性透射）、（2）水泥–骨界面增寬多於2毫米、（3）股骨柄上外側假體與水泥 間的透亮帶多於2毫米（下沉）、（4）在所有Gruen分區內股骨柄假體與水泥的透亮帶多於1毫米、 （5）股骨柄尖端骨質硬化及增厚及（6）膠結不足（按Barrack分級為C或D級，或在任何Gruen分區 內水泥厚度少於2毫米）。
結果：六項放射學特徵中，水泥–骨界面增寬、假體下沉及膠結不足均提示水泥股骨柄假體有鬆 動，校正後比數比分別為17.4（p = 0.003）、10.3（p = 0.026）及7.5（p = 0.040）。其中假體下沉和 水泥–骨界面增寬兩項特徵的評估者間一致性為最高（kappa值分別為0.60和0.56)。
結論：本研究發現X線平片中水泥–骨界面增寬、假體下沉及膠結不足為提示水泥股骨柄假體鬆動 的最有效指徵。