Bagaria Vaibhav, Tiwari Anjali
Director and Consultant, Department of Orthopedic Surgery, Sir H N Reliance Foundation Hospital, Girgaum, Mumbai 400004, Maharashtra, India.
Research Analyst, Department of Orthopedic Surgery, Sir H N Reliance Foundation Hospital, Girgaum, Mumbai 400004, Maharashtra, India.
SICOT J. 2025;11:42. doi: 10.1051/sicotj/2025038. Epub 2025 Jul 23.
Severe varus knee osteoarthritis (OA) alters weight-bearing mechanics, leading to progressive stress concentration on the posteromedial tibial plateau. In select cases, this results in the development of a Posteromedial Varus Fatigue Fragment (PVFF), a chronic stress-related fracture that remains ununited and influences knee stability, surgical planning, and implant selection. This study aims to evaluate the incidence, radiographic detectability, and intraoperative significance of PVFF in patients undergoing total knee arthroplasty (TKA).
A retrospective analysis was conducted of 856 consecutive TKA cases performed by a single surgeon. Preoperative radiographs, intraoperative findings, and surgical modifications were assessed to determine the incidence and implications of PVFF. Correlation with varus severity and absence of ACL was done.
PVFF was detected intraoperatively in 17 of 856 cases (1.99%), but only 9 (53%) were visible on pre-op imaging." All PVFF cases exhibited varus alignment exceeding 15° and complete ACL deficiency. Intraoperatively, fragment removal resulted in an increased medial flexion gap, impacting gap balancing and necessitating adjustments in implant selection, including the use of tibial stems or augments in select cases.
PVFF is an underrecognized structural lesion for precision in severe varus knee OA, affecting tibial fixation, load distribution, and medial knee stability. Its presence requires careful intraoperative assessment, as fragment removal can alter gap balancing. Improved preoperative recognition and surgical planning are essential to optimize TKA outcomes in patients. Further prospective studies and biomechanical analyses are needed to better understand PVFF's long-term clinical implications and refine surgical strategies.
重度膝内翻骨关节炎（OA）会改变负重力学，导致胫骨后内侧平台出现渐进性应力集中。在某些情况下，这会导致后内侧内翻疲劳骨折块（PVFF）的形成，这是一种与慢性应力相关的骨折，一直未愈合，并影响膝关节稳定性、手术规划和植入物选择。本研究旨在评估全膝关节置换术（TKA）患者中PVFF的发生率、影像学可检测性及术中意义。
对由单一外科医生连续进行的856例TKA病例进行回顾性分析。评估术前X线片、术中发现及手术调整情况，以确定PVFF的发生率及影响。分析其与内翻严重程度及前交叉韧带缺失情况的相关性。
856例病例中有17例（1.99%）术中检测到PVFF，但术前影像学检查仅发现9例（53%）。所有PVFF病例均表现为内翻畸形超过15°且前交叉韧带完全缺失。术中，去除骨折块导致内侧屈曲间隙增加，影响间隙平衡，需要调整植入物选择，包括在某些情况下使用胫骨柄或垫块。
PVFF是重度膝内翻OA中一种未被充分认识的结构病变，影响胫骨固定、负荷分布及膝关节内侧稳定性。其存在需要术中仔细评估，因为去除骨折块会改变间隙平衡。改善术前识别和手术规划对于优化患者TKA结局至关重要。需要进一步的前瞻性研究和生物力学分析，以更好地理解PVFF的长期临床意义并完善手术策略。
