Is cementing technique the cause of early aseptic loosening of the tibial component in total knee arthroplasty? A report of 22 failed tibial components
Despite excellent results of bicondylar knee resurfacing when both the tibial and femoral components are cemented, loosening of the cemented tibial component (surface cementing) occurs in approximately 10% of the implants within a 4-year interval after the procedure. Based on our own experience, we want to report of early failed tibial components in 22 patients after a mean follow up of 51 months, necessitating a revision procedure. We analysed retrospectively 22 cases of failed tibial components in patients after a mean follow up of 51 months, necessitating a revision procedure. This raised the question of whether the cementing technique was implicated in the loosening. Every correlation between early loosening and clinically relevant covariates were investigated. All patients were evaluated for radiolucency and osteolytic lesions at the bone–cement interfaces by radiographic assessment according to Rossi et al. (a.p. view and lateral view divided into two zones). The mean radiographic cement penetration in anterior-posterior view was 1.2 mm (SD 0.8) in zone 1 and 1.6 mm (SD 0.9) in zone 2. The mean radiographic cement penetration in lateral view was 1.1 mm (SD 0.4) in zone 1 and 1.3 mm (SD 0.3) in zone 2. Osteolytic lesions were seen in all cases around the implant after a mean of 51 months. In all cases a revision procedure was done. Based on clinical presentation, haematological screening, joint aspiration (synovial fluid diagnostic, microbiological analyses) and histological evaluation of intraoperative samples an infection was excluded. The authors have a critical attitude toward a loosening rate of almost 10% as stated by the recent literature within the first 4 to 5 years and consider that a reduction of the loosening rate when using the full cementation technique /cementing the stem) will mean a greater benefit for patients than the possible advantage of a better bone stock in case of revision surgery. Apart from this aspect, the question of whether early aseptic loosening is still acceptable nowadays from the medical economic aspects also warrants discussion.
Orthopaedics, TKA, early failure, cementing technique