A randomized controlled clinical and radiological trial about outcomes of navigation-assisted TKA compared to conventional TKA: long-term follow-up

PURPOSE

Well balanced knees with good alignment are essential for a well-functioning TKA with long survival of its implants. This prospective randomized study comparing navigation-assisted TKA and conventional TKA reported the clinical and radiological outcomes at a follow-up of 9 years. The purpose of this study was to compare the clinical and radiological outcomes for patients who underwent navigation-assisted TKA or conventional TKA after long-term follow-up.

METHODS

A total of 80 patients (88 knees) were available for physical and radiological examination 9 years after TKA. Clinical outcomes were evaluated using HSS, WOMAC, and KS function and pain scores. And radiological outcomes of the component loosening and its survivorship during 9-year follow-up were also evaluated.

RESULTS

There were no significant differences in the field of clinical outcomes between the two groups. In terms of radiological outcomes, the navigation group had fewer alignment outliers (7.3 vs 20 %, p = 0.006). Although the clinical outcomes showed no differences between the two groups, the survival rate was slightly better in the navigation group than in the conventional group without statistical significance (best-case scenario 100 vs 95.3 %, n.s., worst-case scenario 95.6 vs 88.4 %, n.s.).

CONCLUSION

Navigation-assisted TKA produced better alignment outcomes and better survival rates than conventional instruments although some of the differences were not statistically significant.

LEVEL OF EVIDENCE

I.

Single-Stage Corrective Osteotomies for Multiple Angular Deformities Around the Knee Joint with Patellar Instability in a Patient with Multiple Epiphyseal Dysplasia: A Case Report

CASE

It is rare to find a case report on combined recurvatum and valgus deformity of the knee with associated patellar instability due to a depressed lateral tibial plateau in a young adult with multiple epiphyseal dysplasia. We treated such a patient with single-stage osseous and soft-tissue procedures and achieved a stable, well-aligned, pain-free, and mobile joint.

CONCLUSION

Patellar instability with genu recurvatum and genu valgum leading to reduced range of motion of the knee in multiple epiphyseal dysplasia shows mechanical and functional improvement following single-stage surgical intervention, thereby improving quality of life.

Induction of metallothionein in a human trophoblast cell line by cadmium and zinc

The induction of metallothionein (MT) in a cell line derived from a malignant trophoblastic tumor (JAr cells) was demonstrated using the Cd/heme radioassay following exposure to Cd or Zn. Cd at an optimal concentration of 1 microM produced a 30-fold increase in MT following a 24 hr incubation. Induction by Cd was both time and dose dependent, with a significant increase in MT noted as early as 3 hr, with levels continuing to increase up to 24 hr. Zn was also quite effective in inducing MT synthesis in this cell line. Exposure to 80 microM Zn for 24 hr produced a 70-fold increase in MT. Although Cd was a more potent inducer of MT, exposure to Zn resulted in a greater magnitude of induction. The magnitude of MT induction in JAr cells was much greater than that seen in cultured trophoblasts from term chorion laeve. The degree of induction seen in this cell line makes it an interesting model for the study of MT's role in trophoblast function. MT induction in trophoblasts may reflect a protective mechanism against heavy metal toxicity and/or an integral aspect of normal zinc homeostasis.