Cementless tibial components have excellent implant survivorship with no cases of aseptic tibial loosening at 10 years follow up

The popularity of cementless total knee arthroplasty (TKA) is on the rise because of innovations in implant designs and surgical technique as well as the fact that greater than 50% of TKAs are performed in patients less than age 65 years. The 2021 American Joint Replacement Registry report indicates that 14% of all primary TKAs are cementless.

E. Gibon et al. conducted Randimized Control Trial with three arms at ‘Department of Orthopedic Surgery, Mayo Clinic, Rochester, Minnesota’ after approval from institutional review board and with specific written informed consent. This study has been awarded ‘John N. Insall Award’ at the 2023 Knee Society Awards.

389 primary TKAs were randomized: traditional modular cemented tibia (135); hybrid (cemented baseplate with uncemented pegs) monoblock tibia (128); and cementless monoblock tibia (126).

The inclusion criteria included patients aged 20 to 85 years, who underwent unilateral TKA for end-stage knee disease secondary to degenerative or post-traumatic arthritis. The exclusion criteria included patients younger than 20 years or older than 85 years, severe deformity with greater than 20º of varus, valgus, or fixed flexion deformity, history of infection, major musculoskeletal or neurological disorders, or disease that may adversely affect normal gait or weight-bearing, metastatic disease, any congenital, developmental, or other bone disease or previous knee surgery that may interfere with total knee success (eg, Paget’s disease, Charcot’s disease), severe osteoporosis or previous high tibial osteotomy, presence of previous prosthetic knee arthroplasty device, arthrodesis of the affected knee, and/or patients not undergoing patella resurfacing.

Implant survivorships, radiographs, and clinical outcomes were analyzed.

Key findings of the study were:

• Mean age at TKA was 68 years (range, 41 to 85), 46% were male, and mean body mass index was 32 (range, 21 to 59).

• The mean follow-up was 10 years.

• The 10-year survivorship free of any revision was similar between the hybrid monoblock and cementless monoblock groups at 96%, but lower (89%) for the traditional modular cemented tibia (P = .05).

• The traditional modular cemented tibia group had significantly more revisions for aseptic tibial loosening than the other 2 groups (7 versus 0%) at 10 years (P = .003).

• The traditional modular cemented tibia group had significantly more nonprogressive radiolucent lines than the hybrid and cementless monoblock groups (24, 12, and 9%, respectively).

• Clinical outcomes were similar and excellent between all 3 groups.

The authors concluded that - ‘Cementless and hybrid monoblock tibial components have excellent implant survivorship (96%) with no cases of aseptic tibial loosening to date. The traditional cemented modular tibial group had a 7% cumulative incidence of aseptic loosening at 10 years.’

Level of Evidence: Level I, Prospective Randomized Control Trial.

Further reading:

John N. Insall Award: Randomized Clinical Trial of Cementless Versus Cemented Tibial Components: Durable and Reliable at a Mean 10-Years Follow-Up

E. Gibon et al.

The Journal of Arthroplasty 38 (2023) S14-S20

https://doi.org/10.1016/j.arth.2023.03.015