Ramappa Manjunath, Port Andrew
James Cook University Hospital, Middlesbrough, UK.
J Med Case Rep. 2009 Feb 10;3:59. doi: 10.1186/1752-1947-3-59.
Knee pain is a complex problem that can occur after total knee arthroplasty. One cause of knee pain may be due to a retained osteophyte, but it is not clear if the retained osteophyte is sufficient explanation of the pain, as not all patients with retained osteophytes are symptomatic. In fact, the literature shows that excised osteophytes can also recur over a period of time, without any symptoms. Therefore a retained osteophyte alone is probably not sufficient to cause symptoms.
We present a case of intermittent medial knee pain occurring post-primary total knee arthroplasty, in a patient who underwent several investigations over a period of 5 years. Radiographs showed an osteophyte in the postero-medial femur along with slight tibial component overhang which was normal for that knee implant design. The symptoms eventually settled with excision of only the osteophyte, without altering the tibial component.
A retained osteophyte alone, or tibial component overhang alone, did not seem to cause significant symptoms in our patient whose symptoms completely settled with excision of the osteophyte alone, without changing the tibial component. Therefore, it seems that the combination of retained osteophyte and tibial component overhang (tibia-femoral component size mismatch) are detrimental and therefore best avoided. This report also emphasises the importance of meticulous osteophyte excision and avoiding tibial component overhang during knee arthroplasty.
膝关节疼痛是全膝关节置换术后可能出现的复杂问题。膝关节疼痛的一个原因可能是残留骨赘，但尚不清楚残留骨赘是否足以解释疼痛，因为并非所有有残留骨赘的患者都有症状。事实上，文献表明切除的骨赘也可能在一段时间后复发，且无任何症状。因此，仅残留骨赘可能不足以引起症状。
我们报告一例初次全膝关节置换术后出现间歇性膝关节内侧疼痛的病例，该患者在5年时间里接受了多项检查。X线片显示股骨后内侧有一个骨赘，以及胫骨部件轻微悬突，这对于该膝关节植入物设计来说是正常的。症状最终通过仅切除骨赘而得到缓解，未改变胫骨部件。
在我们的患者中，单独的残留骨赘或单独的胫骨部件悬突似乎并未引起明显症状，该患者的症状通过仅切除骨赘而完全缓解，未更换胫骨部件。因此，似乎残留骨赘和胫骨部件悬突（胫股部件尺寸不匹配）的组合是有害的，因此最好避免。本报告还强调了在膝关节置换术中细致切除骨赘和避免胫骨部件悬突的重要性。
