Steadman Philippon Research Institute, Vail, Colorado, USA.
Santa Monica Orthopaedic Group, Santa Monica, California, USA.
Am J Sports Med. 2019 Feb;47(2):501-507. doi: 10.1177/0363546517743734. Epub 2017 Dec 18.
The cause of spontaneous osteonecrosis of the knee (SONK) and postarthroscopic osteonecrosis of the knee is unknown, and the mechanisms involved have been poorly characterized.
HYPOTHESIS/PURPOSE: The purpose of this study was to perform a detailed systematic review of the literature to examine proposed etiological mechanisms for SONK in order to establish an improved understanding of the processes involved. We hypothesized that the etiology of SONK would be multifactorial.
Systematic review.
A systematic review of the literature was performed by searching PubMed, Medline, Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials. Inclusion criteria were all original research articles presented in the English language that reported on the suspected etiology of SONK. Reviews, case reports with fewer than 3 patients, cost-effectiveness studies, technical reports, editorial articles, surveys, special topics, letters to the editor, personal correspondence, and studies that only proposed factors for the progression of SONK were excluded.
After a comprehensive review of 255 articles, 26 articles were included for final analysis. Twenty-one (80.7%) of 26 articles implicated the role of the meniscus in the development of SONK, in an association with either meniscal tears or its development after meniscectomy. The medial meniscus and posterior meniscal root tears were implicated more frequently. All 4 studies incorporating histological findings supported the insufficiency fracture hypothesis as a pathological basis of SONK.
Physicians should be cognizant of the high prevalence of medial meniscus root tears in patients with SONK. Meniscectomy and meniscal tears, particularly of the medial meniscus posterior root, increase contact pressures and create an environment from which insufficiency fractures can emanate. We believe the term SONK is a misrepresentation of the etiology and pathogenesis of the condition and should be replaced with subchondral insufficiency fractures of the knee. Further elucidation of the etiology is required.
膝关节自发性骨坏死（SONK）和膝关节关节镜检查后骨坏死的病因尚不清楚，其涉及的机制也尚未得到充分描述。
假设/目的：本研究旨在对文献进行详细的系统回顾，以检查 SONK 的拟议病因学机制，从而更好地了解所涉及的过程。我们假设 SONK 的病因是多因素的。
系统评价。
通过搜索 PubMed、Medline、Cochrane 系统评价数据库和 Cochrane 对照试验中心注册库，对文献进行系统评价。纳入标准为所有以英文发表的报告 SONK 疑似病因的原始研究文章。排除综述、少于 3 例的病例报告、成本效益研究、技术报告、社论文章、调查、专题、给编辑的信、个人通信以及仅提出 SONK 进展因素的研究。
经过对 255 篇文章的全面回顾，有 26 篇文章被纳入最终分析。26 篇文章中有 21 篇（80.7%）认为半月板在 SONK 的发展中起作用，与半月板撕裂或半月板切除后的发展有关。内侧半月板和后半月板根部撕裂更为常见。所有 4 项纳入组织学发现的研究都支持不完整性骨折假说作为 SONK 的病理基础。
医生应该意识到 SONK 患者中内侧半月板根部撕裂的高发生率。半月板切除术和半月板撕裂，特别是内侧半月板后根部，会增加接触压力，并产生不完整性骨折的环境。我们认为，SONK 这一术语是对该疾病病因和发病机制的错误表述，应该用膝关节软骨下不完整性骨折来代替。需要进一步阐明病因。
