2025 ISAKOS Congress in Munich, Germany

2025 ISAKOS Biennial Congress ePoster

 

Comparison Of Clinical Outcomes Between High Tibial Osteotomy And Total Knee Arthroplasty In Older Patients With Severe Osteoarthritis

Kodai Hamaoka, MD, Sapporo, Hokkaido JAPAN
Shinichiro Okimura, MD, PhD, Sapporo, Hokkaido JAPAN
Kazushi Horita, MD, Sapporo, Japan JAPAN
Yasutoshi Ikeda, MD,PhD, Sapporo JAPAN
Yohei Okada, MD,PhD, Sapporo City JAPAN
Tomoaki Kamiya, MD, Sapporo, Hokkaido JAPAN
Atsushi Teramoto, MD, PhD, Sapporo, Hokkaido JAPAN

Department of Orthopaedic Surgery, Sapporo Medical University School of Medicine, Sapporo, Hokkaido, JAPAN

FDA Status Cleared

Summary

The knee injury and osteoarthritis outcome score pain scores after total knee arthroplasty were superior to those after high tibial osteotomy in early older patients with severe osteoarthritis.

ePosters will be available shortly before Congress

Abstract

Background

The clinical outcomes of high tibial osteotomy (HTO) in older patients remain controversial. No study has evaluated the clinical outcomes of HTO compared with total knee arthroplasty (TKA) in early older patients with severe osteoarthritis (OA), leaving the results unclear. In this study, we aimed to compare the clinical outcomes of HTO and TKA in early older patients with severe OA. We hypothesised that satisfactory clinical outcomes could not be attained with HTO in early elderly patients with severe OA.

Methods

In this retrospective study, patients who underwent HTO and TKA for medial knee osteoarthritis were assigned to the HTO and TKA groups, respectively. The inclusion criteria were (1) age 65–74 years (early older), (2) Kellgren–Lawrence grade 4, and (3) a minimum post-operative 2-year follow-up. The exclusion criteria were (1) inflammatory arthritis, (2) symptomatic OA in the lateral compartment, (3) history of ligament surgery, and (4) revision cases. Radiographic data was assessed preoperatively. Femoral tibial angle (FTA), medial proximal tibial angle (MPTA), mechanical lateral distal femoral angle (mLDFA), percentage of the mechanical axis were evaluated as radiographic outcome. Clinical outcomes were assessed using the knee injury and osteoarthritis outcome score (KOOS), minimal clinically important difference (MCID), and patient-acceptable symptom state (PASS) achievement rate for the KOOS subscales at the final follow-up. The t-test, paired t-test, and chi-squared test were used, with

Significance

level of 0.05. Statistical power calculations were performed using G*Power version 3.1.9.6 (Düsseldorf, Germany), with the significance level set at 0.05, effect size of 0.8, and power of 0.8. The minimum sample size required for the study was 70.

Results

The HTO and TKA groups comprised 35 and 40 patients, respectively. The median ages were 69.1 and 71.1 years in the HTO and TKA groups, respectively. Two patients underwent revision osteotomy for lateral hinge fracture. Conversion to TKA after HTO was performed in three patients in the HTO group. Significant differences were observed in the preoperative radiographic parameters in FTA, MPTA, and mLDFA between the two groups. Preoperatively, no significant difference was observed in any of the KOOS subscales between the groups. However, at the final follow-up, the median KOOS pain scores were significantly better in the TKA group (83.3) than in the HTO group (73.4) (p=0.03). No significant differences were observed in the MCID and PASS achievement rates for the KOOS subscales.

Conclusion

The pivotal finding of this study is that the KOOS pain scores after TKA were superior to those after HTO in early older patients with severe OA at a mean follow-up of 54 months. No significant differences were observed in the MCID and PASS achievement rate for all KOOS subscales between the two groups, although three patients in the HTO group underwent conversion to TKA. Our findings suggest that HTO should be limited in older patients with severe OA.