Vind Tobias Dahl, Jørgensen Peter Bo, Vainorius Dovydas, Jakobsen Stig Storgaard, Søballe Kjeld, Stilling Maiken
Department of Orthopaedics, Aarhus University Hospital, Palle Juul-Jensens Boulevard 165, 8200, Aarhus, Denmark.
Aarhus University, Aarhus, Denmark.
Arch Orthop Trauma Surg. 2023 Feb;143(2):1071-1080. doi: 10.1007/s00402-021-04307-y. Epub 2022 Feb 3.
The Exeter short stem (ESS) is 25 mm shorter than the standard length v40 Exeter stem (Stryker) and intended for a narrow femoral diaphysis. The purpose of the study was to evaluate the migration pattern of the cemented ESS.
In a prospective single-center cohort study, 23 patients (21 female) mean age 78 (range 70-89) with hip osteoarthritis and Dorr Type A femurs were included. Preoperative DXA was used to group patients into normal (> - 1) and low (< - 1) T-score. Components were the collarless polished double-tapered Exeter short stem type N°1 L125. Patients were followed for 2 years with model-based RSA (stem migration), regular hip radiographs (stem position and cementation quality), Oxford Hip Score (OHS) and VAS pain.
At 2-year follow-up, the stems subsided 1.48 mm (CI 95% 1.69; 1.26) and retroverted 0.45° (CI 95% 0.01; 0.88). From 12 to 24 months, stem subsidence was 0.18 mm (CI 95% 0.1; 0.25) (p = 0.001) and retroversion was - 0.04° (CI 95% - 0.27; 0.18) (p = 0.70). T-score and stem subsidence correlated (rho = 0.48; p = 0.025) and patients with normal T-score (n = 7) had 0.42 mm (CI 95% - 0.01; 0.85) less subsidence as compared to patients with low T-score (n = 15) (p = 0.054). Stems in varus position (n = 9) subsided 1.7 mm (CI 95% 1.35; 2.05) compared to 1.33 mm (CI 95% 1.05; 1.60) for stems in neutral position (n = 13) (p = 0.07). Postoperative cementation quality did not influence 2-year stem migration. OHS improved to 40.7 (CI 95% 36.8; 44.7) and VAS pain at rest and activity decreased to 5 mm and 10 mm, respectively (p < 0.001).
The 2-year migration pattern of the cemented ESS was similar to reports for the cemented standard length Exeter stem. Low preoperative T-score and varus stem-position showed a tendency for higher stem migration and should be studied as risk factors for failure in larger studies of cemented polished stems.
埃克塞特短柄（ESS）比标准长度的v40埃克塞特柄（史赛克公司）短25毫米，适用于股骨干狭窄的情况。本研究的目的是评估骨水泥型ESS的移位模式。
在一项前瞻性单中心队列研究中，纳入了23例髋骨关节炎患者（21例女性），平均年龄78岁（范围70 - 89岁），股骨为多氏A型。术前采用双能X线吸收法（DXA）将患者分为T值正常（> -1）和T值低（< -1）两组。植入部件为无领抛光双锥度埃克塞特短柄N°1 L125型。对患者进行了为期2年的基于模型的放射学立体测量分析（RSA，用于柄的移位）、常规髋关节X线片检查（柄的位置和骨水泥质量）、牛津髋关节评分（OHS）以及视觉模拟评分法（VAS）疼痛评分。
在2年随访时，柄下沉1.48毫米（95%置信区间1.69；1.26），后倾0.45°（95%置信区间0.01；0.88）。在12至24个月期间，柄下沉0.18毫米（95%置信区间0.1；0.25）（p = 0.001），后倾为 -0.04°（95%置信区间 -0.27；0.18）（p = 0.70）。T值与柄下沉相关（rho = 0.48；p = 0.025），T值正常的患者（n = 7）比T值低的患者（n = 15）下沉少0.42毫米（95%置信区间 -0.01；0.85）（p = 0.054）。内翻位的柄（n = 9）下沉1.7毫米（95%置信区间1.35；2.05），而中立位的柄（n = 13）下沉1.33毫米（95%置信区间1.05；1.60）（p = 0.07）。术后骨水泥质量不影响柄2年的移位。OHS改善至40.7（95%置信区间36.8；44.7），静息和活动时的VAS疼痛分别降至5毫米和10毫米（p < 0.001）。
骨水泥型ESS的2年移位模式与骨水泥型标准长度埃克塞特柄的报道相似。术前T值低和柄处于内翻位显示出柄移位较高的趋势，应在更大规模的骨水泥抛光柄研究中作为失败的风险因素进行研究。
