The performance of cruciate-retaining implants for primary total knee arthroplasty in valgus deformed knees: A systematic review.

BACKGROUND

Valgus deformity of the knee comprises upwards of 15 % of the deformities in primary total knee arthroplasty (TKA) patients. 1,2 The two implants most commonly used in valgus deformed knees are posterior stabilizing (PS) and cruciate-retaining (CR) implants. CR implants may offer a more advantageous construct due to the retention of the PCL for proprioception and less bony resection compared to PS implants. The purpose of this systematic review is to aggregate findings for cruciate-retaining implants used in primary TKA with valgus deformed knees.

METHODS

In compliance with PRISMA guidelines, databases were queried for CR TKA studies which met the inclusion criteria. Cochrane ROBINS-I and the GRADE framework assessed bias and quality respectively.

RESULTS

There was a statistically significant (p < 0.001) difference between preoperative and postoperative valgus deformity as measured by tibiofemoral angle. The all-cause revision rate was 8.3 % in our sample of 710 total knee arthroplasties.

CONCLUSION

This review of the literature demonstrates that, although scarcely reported, cruciate-retaining implants used in primary total knee arthroplasties in valgus deformed knees provide satisfactory outcomes such as arc of motion and knee score. Our results demonstrate a significant increase in all-cause revision when using CR implants for valgus deformed knee. For this reason, further investigations should be conducted to evaluate modes of failure in this specific patient population.

LEVEL OF EVIDENCE: IV systematic review.