Kiapour Ata M, Fleming Braden C, Proffen Benedikt L, Murray Martha M
Sports Medicine Research Laboratory, Department of Orthopaedic Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Department of Orthopaedics, Warren Alpert Medical School of Brown University & Rhode Island Hospital, Providence, Rhode Island, USA.
Am J Sports Med. 2015 Jul;43(7):1623-31. doi: 10.1177/0363546515582024. Epub 2015 May 4.
The risk of anterior cruciate ligament (ACL) injury is 2 to 10 times greater in women than men. While the effect of sex on injury risk is well established, its effects on surgical outcomes remain controversial.
PURPOSE/HYPOTHESIS: To investigate whether the biomechanical outcomes of ACL reconstruction are affected by sex using an established porcine model that displays similar sex-specific differences in knee anatomy and ligament structural properties to humans. The hypothesis was that there will be sex differences in ACL reconstruction outcomes with regard to the graft structural properties, knee laxity, and cartilage damage.
Controlled laboratory study.
A total of 41 adolescent Yucatan minipigs (23 male, 18 female) underwent unilateral ACL transection and ACL reconstruction using sex-matched bone-patellar tendon-bone allografts (with or without additional bioenhancement). Graft biomechanical and histological properties, knee laxity, and cartilage damage were assessed after 15 weeks. A 2-factor analysis of variance was used to investigate the effect of sex on all the measured outcomes after adjusting for the treatment effect.
After 15 weeks of healing, female pigs had a significantly lower mean normalized graft yield load (by 18.5% ± 7.7%; P = .023) and linear stiffness (by 11.9% ± 5.6%; P = .043) compared with male pigs. Female pigs had significantly greater side-to-side differences in anteroposterior knee laxity at 30° (by 1.4 ± 0.6 mm; P = .028) and 90° (by 1.8 ± 0.8 mm; P = .032). Female pigs had a lower graft vascular density (by 0.8 ± 0.3 [analog scoring]; P = .021) with similar cellular and collagen-based histologic scores in both sexes (P > .6). Female pigs also had a significantly larger area of cartilage damage (by 43.3 ± 14.8 mm(2); P = .014) after conventional ACL reconstruction compared with their male counterparts.
Female pigs had significantly worse outcomes (ie, graft structural properties, knee laxity, and cartilage damage) compared with male pigs in this translational model after 15 weeks of healing.
These data suggest that further optimization of ACL injury treatments may be needed to accommodate each sex instead of using a "one fits all" approach to improve surgical outcomes, decrease incidence of reinjury, and decrease posttraumatic osteoarthritis risk after ACL reconstruction.
女性前交叉韧带（ACL）损伤的风险是男性的2至10倍。虽然性别对损伤风险的影响已得到充分证实，但其对手术结果的影响仍存在争议。
目的/假设：使用已建立的猪模型来研究ACL重建的生物力学结果是否受性别影响，该模型在膝关节解剖结构和韧带结构特性方面显示出与人类相似的性别特异性差异。假设是在移植物结构特性、膝关节松弛度和软骨损伤方面，ACL重建结果会存在性别差异。
对照实验室研究。
总共41只青春期尤卡坦小型猪（23只雄性，18只雌性）接受了单侧ACL横断，并使用性别匹配的骨 - 髌腱 - 骨同种异体移植物（有或没有额外的生物增强）进行ACL重建。15周后评估移植物的生物力学和组织学特性、膝关节松弛度和软骨损伤情况。在调整治疗效果后，使用双因素方差分析来研究性别对所有测量结果的影响。
愈合15周后，与雄性猪相比，雌性猪的平均归一化移植物屈服载荷显著更低（降低18.5%±7.7%；P = 0.023），线性刚度也显著更低（降低11.9%±5.6%；P = 0.043）。雌性猪在30°（差值为1.4±0.6毫米；P = 0.028）和90°（差值为1.8±0.8毫米；P = 0.032）时前后向膝关节松弛度的左右差异显著更大。雌性猪移植物血管密度更低（差值为0.8±0.3[模拟评分]；P = 0.021），而两性的细胞和基于胶原蛋白的组织学评分相似（P > 0.6）。与雄性猪相比，雌性猪在传统ACL重建后软骨损伤面积也显著更大（差值为43.3±14.8平方毫米；P = 0.014）。
在这个转化模型中，愈合15周后，与雄性猪相比，雌性猪的结果（即移植物结构特性、膝关节松弛度和软骨损伤）明显更差。
这些数据表明，可能需要进一步优化ACL损伤治疗方法，以适应不同性别，而不是采用“一刀切”的方法来改善手术结果、降低再损伤发生率以及降低ACL重建后创伤性骨关节炎的风险。
