Implant migration and clinical outcomes with cemented vs cementless Motec cups in total trapeziometacarpal arthroplasty: a 10-year prospective RSA cohort study of 69 patients
Prospective cohort study finds comparable 10-year migration between cemented and cementless cups in thumb arthroplasty, indicating that early movement predicts implant revision.
Key Points
To evaluate 10-year cup migration, clinical outcomes, and revision rates of cementless versus cemented Motec cups in total trapeziometacarpal arthroplasty, and investigate early migration predictors of cup revision.
Prospective cohort study of 69 patients undergoing trapeziometacarpal arthroplasty with cementless titanium-screw cups (n = 22, 2009–2010) or cemented all-polyethylene cups (n = 47, 2011–2012).
Radiostereometric analysis (RSA) was performed at 3 weeks (baseline), 3 months, and 1, 2, 5, and 10 years to measure cup total translation alongside prospective monitoring of pain, grip strength, QuickDASH scores, and revisions.
At 10 years, mean cup total translation was 0.79 mm (SE 0.55) for cementless cups (n = 3) and 1.33 mm (SE 0.30) for cemented cups (n = 10), with cemented cups exhibiting 0.54 mm (95% CI -0.68 to 1.77) greater translation.
Revisions occurred in 10 of 22 cementless cups and 15 of 47 cemented cups primarily due to aseptic loosening, with revised cups showing significantly higher total translation than non-revised cups at 1 year for cementless (difference: 1.75 mm, 95% CI 0.45 to 3.05) and at 2 years for cemented (difference: 1.11 mm, 95% CI 0.30 to 1.93).
Increased pain during activity and higher QuickDASH scores were strongly associated with cup revision, whereas patients with retained cups at 10 years maintained high satisfaction and clinically meaningful improvements in pain, grip strength, and function.