Townsend Sarah, Kim Stanley E, Pozzi Antonio
Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida.
Department for Small Animal Surgery, Vetsuisse Faculty, University of Zurich, Zurich, Switzerland.
Vet Surg. 2017 Aug;46(6):803-811. doi: 10.1111/vsu.12666. Epub 2017 Apr 29.
To determine the influence of stem sizing and positioning with early subsidence and stem complications with cementless (BFX) total hip arthroplasty (THA).
Retrospective case series.
Fifty-five dogs; 58 THAs.
Eighty cobalt-chromium BFX THAs were reviewed, 58 met inclusion criteria. Implant size, positioning, and major complications within 12 months of surgery were recorded. Femoral canal flare (FCF), canal fill, stem angle, and subsidence at 3 months were measured from postoperative radiographs. Appropriateness of final stem size was assessed with digital templates. Odds ratios for associations were calculated.
Mean ± SD coronal canal fill (Fill ) was 75% ± 6, FCF was 2.0 ± 0.3, and subsidence was 1.7 mm ± 2.6. Stem angulation ranged from 7° varus to 6° valgus, and 7° cranial to 3° caudal. Appropriately sized stems (n = 45) had a mean Fill of 78%. Major stem complications occurred in 12% of THAs. Femora with subsidence > 3 mm were 45.3 times more likely to develop postoperative stem complications (P = .02). Stems with varus angulation ≥ 5° were 12.5 times more likely to sustain intraoperative fissures (P = .03). Stems considered undersized based on postoperative digital templating were 5.6 times more likely to develop stem complications (P = .04) and 5.7 times more likely to subside > 3 mm (P = .03).
Varus stem angulation should be avoided to prevent fissures. Canal fill is a poor indicator of optimal stem size and the current recommendation of >85% is unnecessarily high. Postoperative templating may be useful for assessing appropriateness of stem size.
确定在非骨水泥型（BFX）全髋关节置换术（THA）中，柄的尺寸和位置对早期下沉及柄相关并发症的影响。
回顾性病例系列研究。
55只犬；58例全髋关节置换术。
回顾了80例钴铬合金BFX全髋关节置换术，58例符合纳入标准。记录植入物尺寸、位置以及术后12个月内的主要并发症。从术后X线片测量股骨髁上峡部（FCF）、髓腔填充、柄角度以及3个月时的下沉情况。用数字模板评估最终柄尺寸的合适性。计算关联的优势比。
平均±标准差冠状面髓腔填充（Fill）为75%±6，FCF为2.0±0.3，下沉为1.7mm±2.6。柄角度范围从内翻7°到外翻6°，以及头倾7°到尾倾3°。尺寸合适的柄（n = 45）平均Fill为78%。12%的全髋关节置换术发生了主要柄并发症。下沉>3mm的股骨发生术后柄并发症的可能性高45.3倍（P = 0.02）。内翻角度≥5°的柄发生术中裂缝的可能性高12.5倍（P = 0.03）。根据术后数字模板判断为尺寸过小的柄发生柄并发症的可能性高5.6倍（P = 0.04），下沉>3mm的可能性高5.7倍（P = 0.03）。
应避免柄内翻角度以防止裂缝。髓腔填充不是最佳柄尺寸的良好指标，目前>85%的建议过高。术后模板可能有助于评估柄尺寸的合适性。
