Franck Florent, Ouanezar Hervé, Jacquel Alexandre, Pibarot Vincent, Wegrzyn Julien
Department of Orthopedic Surgery-Pavillon T, Hôpital Edouard Herriot, Hospices Civils de Lyon, 5, place d'Arsonval, 69437, Lyon, France.
INSERM UMR 1033, Université de Lyon, Lyon, France.
Int Orthop. 2018 May;42(5):1051-1060. doi: 10.1007/s00264-017-3630-z. Epub 2017 Sep 9.
The decision to resurface the patella during total knee arthroplasty (TKA) remains controversial. This prospective cohort study aimed to evaluate the outcome and survivorship of the native patella in computer-assisted TKA (CAS TKA) implanted for primary knee osteoarthritis, and to determine the predictive factors of secondary patellar resurfacing (SPR).
A prospective cohort of 273 cementless ultra-congruent mobile-bearing CAS TKA implanted without patellar resurfacing was included in our total joint registry. Patients were evaluated with the International Knee Society (IKS) and Hospital for Special Surgery Patellar (HSSP) scores. Radiographic evaluation was focused on the patellofemoral (PF) compartment to assess: the patellar dysplasia (Wiberg classification), PF osteoarthritis (Iwano classification), femoral trochlear dysplasia (femoral sulcus angle), patellar maltracking (patellar tilt and lateralization), and patella height (Blackburne-Peel ratio).
At a six-year median follow-up, the CAS TKA survivorship using SPR as end-point was 95% (range, 91-99%). The IKS and HSSP improved significantly after SPR (p = 0.001 and 0.004, respectively). No significant difference in the IKS and HSSP was detected between TKA with native patella and SPR-TKA at latest follow-up. Importantly, four pre-operative radiographic PF parameters were significantly associated with SPR: higher stages of patellar dysplasia and PF osteoarthritis, and higher sulcus angle and patellar lateralization (hazard ratios = 5.1 to 11.6, p = 0.009 to 0.04).
When preserving the native patella, surgeons should be aware of pre-operative PF radiographic parameters that could influence the outcome and survivorship of CAS TKA leading to SPR. Particularly, evidence of PF dysplasia, osteoarthritis and maltracking should be determined pre-operatively to resurface the patella at the time of TKA.
Therapeutic Level II (prospective cohort study).
全膝关节置换术（TKA）中是否对髌骨进行表面置换的决定仍存在争议。这项前瞻性队列研究旨在评估在计算机辅助全膝关节置换术（CAS TKA）中，为原发性膝关节骨关节炎植入的天然髌骨的结局和生存率，并确定二次髌骨表面置换（SPR）的预测因素。
我们的全关节登记处纳入了273例未进行髌骨表面置换的非骨水泥型超匹配活动平台CAS TKA的前瞻性队列。采用国际膝关节协会（IKS）和特种外科医院髌骨（HSSP）评分对患者进行评估。影像学评估集中在髌股（PF）关节腔，以评估：髌骨发育不良（Wiberg分类）、PF骨关节炎（Iwano分类）、股骨滑车发育不良（股骨沟角）、髌骨轨迹不良（髌骨倾斜和侧方移位）以及髌骨高度（Blackburne-Peel比率）。
在六年的中位随访期，以SPR为终点的CAS TKA生存率为95%（范围91%-99%）。SPR后IKS和HSSP显著改善（分别为p = 0.001和0.004）。在最新随访时，保留天然髌骨的TKA与SPR-TKA之间，IKS和HSSP未检测到显著差异。重要的是，四个术前影像学PF参数与SPR显著相关：更高阶段的髌骨发育不良和PF骨关节炎，以及更高的沟角和髌骨侧方移位（风险比=5.1至11.6，p = 0.009至0.04）。
在保留天然髌骨时，外科医生应了解可能影响CAS TKA导致SPR的结局和生存率的术前PF影像学参数。特别是，术前应确定PF发育不良、骨关节炎和轨迹不良的证据，以便在TKA时对髌骨进行表面置换。
治疗性二级（前瞻性队列研究）。
