Summary

Distal tibial tubercle osteotomy in open-wedge high tibial osteotomy may represent a patellofemoral-sparing procedure

Abstract

Background

Open-wedge high tibial osteotomy (OWHTO) is classically performed with an ascending osteotomy behind the tibial tuberosity (TT), however, known to affect the patella height, respectively the patellofemoral joint. Alternatively, the osteotomy behind the TT can be performed in a descending way, probably less affecting the patellofemoral joint. This study compares the radiological results of ascending TT (AT-) and descending TT (DT-) OWHTO.

Methods

All patients who underwent AT-OWHTO or DT-OWHTO between October 2014 to December 2022 were included. Coronal and sagittal alignment measurements, patella height and tibial tuberosity-trochlear groove distance (TTTG) were measured preoperatively and at 4.5 and 12 months postoperatively.

Results

A total of 106 knees (55 right, 51 left) from 103 patients (20 females, 83 males) were included, with 48 AT- and 58 DT-OWHTO. Caton-Deschamps index (CDI) changed significantly in AT-OWHTO (preoperatively 0.8 ± 0.1, postoperatively 0.7 ± 0.1, p < 0.001), and remained stable in DT-OWHTO (pre- and postoperatively 0.8 ± 0.1, p = n.s.). TTTG significantly changed in AT-OWHTO (preoperatively 12.6 ± 5.4 mm, postoperatively 14.9 ± 4.6 mm, p < 0.001), and remained stable in DT-OWHTO (preoperatively 13.9 ± 5.4 mm, postoperatively 13.3 ± 5.0 mm, p = n.s.).

Conclusion

A significant decrease of the patella height and a significant increase of the TTTG can be observed in AT-OWHTO, whereas these parameters remain stable in DT-OWHTO. This may indicate DT-OWHTO to be a patellofemoral-sparing procedure, probably be preferable in patients with concomitant patellofemoral degeneration.