Trabecular metal Modular tibial tray knees has better functional outcome than monoblock tibial tray knees: study

Total knee arthroplasty is one of the significantly evolving procedures with different knee designs available in the market. The continued development of these prosthesis resulted in improvement of the implant survivorship and patient satisfaction.

Safa Abulhail conducted an RCT-based meta-analysis aimed to compare two designs of total knee replacement: the conventional modular and the monoblock trabecular metal tibial trays. The article has been published in "international orthopedics" journal.

The meta-analysis was performed by a literature review according to the PRISMA guidelines. A detailed search of the English literature was done using the PubMed, Medline, CINAHL, Cochrane, Embase, and Google Scholar databases. Only randomized control trials were included in the analysis after ensuring homogeneity. Extracted outcome measures were Knee Society score, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, survivorship, complication rate, and radiostereographic analysis(RSA).

Key findings of the study were:

• Seven randomized control trials with 635 patients were eligible for analysis after they met the inclusion criteria.

• 312 patients received monoblock tibias, and the other 323 patients received modular tibial trays during their total knee arthroplasty surgeries.

• There were statistically significant superiority of the modular knees in the functional Knee Society and WOMAC scores at five years (P=0.003 and 0.05, respectively).

• The modular design was also more stable on RSA at two years (P<0.0001).

The authors concluded that – "Modular and monoblock tibial trays are viable options for TKA with almost equivalent survivorship and complication rates over five years. However, the modular tibial trays were significantly more stable, with lower maximal total point motion at two years; they also had significantly better functional outcomes at two to five years. Further long-term, high-quality studies are required to determine the superiority of either design."

Further reading:

Trabecular metal monoblock versus modular tibial trays in total knee arthroplasty: meta analysis of randomized control trials

Safa Abulhail, Shamsi Hameed et al

International Orthopaedics (2022) 46:2509–2516https://doi.org/10.1007/s00264-022-05553-4