Open Wedge High Tibial Osteotomy with Distal Tubercle Osteotomy Lessens Change in Patellar Position

Abstract

The purpose of this study was to investigate the change in patellar position after open wedge high tibial osteotomy (OWHTO) with distal tubercle osteotomy (DTO), comparing outcomes of conventional OWHTO in young adults with proximal tibia varus deformity but no arthritic manifestations. Thirty-three patients (mean age, 31.8 years) subjected to OWHTO/DTO were matched with 30 patients (mean age, 33.5 years) undergoing conventional OWHTO. Patellar position, as measured in pre- and postoperative standing lateral radiographs, was compared. Patellar height was assessed via Insall-Salvati ratio, modified Insall-Salvati ratio, Blackburne-Peel (BP) index, Caton-Deschamps (CD) index, and modified Miura-Kawamura index. Computed tomography was used to measure lateral patellar tilt and shift. In the OWHTO group, all patellar height indices decreased significantly following surgery. Although mean values of BP and CD indices decreased significantly in the OWHTO/DTO group, other determinants of patellar height showed no significant postoperative differences. Significant postoperative declines in average lateral patellar tilt were also evident in both groups, but pre- and postoperative lateral patellar shift did not differ significantly. OWHTO/DTO can be performed without significant changes in patellar height. The results obtained support that OWHTO/DTO is suitable for relatively young patients with proximal tibia vara but no arthritic change.

Patellar Height Is Not Altered When the Knee Axis Correction Is Less than 15 Degrees and Has Good Short-Term Clinical Outcome

“…For another reason, the change in tibial rotation after OWHTO may affect the LPT. 26 In our study, we also found that TT-TG distance showed a significant decrease after OWHTO. In our point of view, one possible explanation for this phenomenon is that the rotation of the distal tibia affects the TT-TG distance.…”

“…These researchers believed that BPI and CDI should not be relied upon in surgical procedures involving the proximal tibia, and they also noted that the MKI reflects a true reduction in patellar height because the measurement is based on femoral and not tibial reference. 23,26 We also did not observe a significant decrease in patellar height when using MKI for measurements. There was no change in patellar height following OWHTO using FPHI for measurements.…”

“…16,19 Recently, OWHTO below the tibial tuberosity has aroused attention and shown significant improvements in radiographic parameters and knee function without changes in patellar height or PTS. [22][23][24][25][26] An early study reported that this technique could lead to the potential for fracture of the tibial tubercle fragment. 45 Park et al also observed two tibial tuberosity fractures with this technique, and they noted that this condition is easily preventable with caution (i.e., leaving at least a 1 cm thickness on the proximal tuberosity fragment).…”

“…45 Park et al also observed two tibial tuberosity fractures with this technique, and they noted that this condition is easily preventable with caution (i.e., leaving at least a 1 cm thickness on the proximal tuberosity fragment). 26…”

“…17 Different surgical techniques also have different influences on patellar height, with some studies suggesting that OWHTO below the tibial tubercle does not affect patellar height. [22][23][24][25][26] Some studies also suggested that patellar height decreases significantly if the knee axis correction is greater than 15 degrees after OWHTO, and patellar tracking will also be seriously affected if the correction of knee axis exceeds 15 degrees. 14,27 Although many studies have reported a change in patellar position after OWHTO, most of these studies used the measurements based on tibial reference, and these measurements should not be relied upon in surgical procedure involving the proximal tibia.…”