Risk of patella baja after opening-wedge high tibial osteotomy

Abstract

Medial opening-wedge high tibial osteotomy (OWHTO) induces a lower patellar position, and the subsequent degree of patellar movement may not be predicted preoperatively. The purpose of this study was to clarify the relationship between preoperative and postoperative patellar height based on the correction angle of OWHTO and to create a formula to predict the appearance of patella baja following OWHTO. Materials and Methods: Seventy-five knees with varus knee osteoarthritis treated with OWHTO were included in this study. The Caton-Deschamps index was used to evaluate patellar height preoperatively and postoperatively, and the cutoff value for preoperative parameters was determined by a receiver operating characteristic curve to determine the risk ratio for postoperative patella baja. Results: The Caton-Deschamps index significantly decreased from 0.93 to 0.77 after OWHTO (p < 0.01). The OWHTO correction angle negatively correlated with the delta Caton-Deschamps index (r ¼ À0.44, p < 0.01), and a 1.7% decrease in the Caton-Deschamps index was shown with a 1 correction angle. Receiver operating characteristic curve analysis revealed that a Caton-Deschamps index of 0.8 was the cutoff for OWHTO; knees with a preoperative Caton-Deschamps index of < 0.8 tended to develop patella baja after OWHTO, with a risk ratio of 9.5 (95% confidence interval [4.3-20.7]). Conclusions: OWHTO can induce patella baja, and a 1.7% decrease in the Caton-Deschamps index was shown with a 1-correction angle. A preoperative Caton-Deschamps index < 0.8 should be considered a risk factor for postoperative patella baja.

The effect of distal tibial tuberosity high tibial osteotomy on postoperative patellar height and patellofemoral joint degeneration

“…In many studies, the correction angle of the weight-bearing line in OWHTO is considered to be related to the change in patella height and the deterioration of the patellofemoral joint. Otsuki et al [ 4 ] found that for every 1° increase in the correction angle, the CDI decreased by 1.7%, and CDI < 0.8 was a risk factor for the occurrence of a low patella after surgery. Yoon et al [ 2 ] conducted a cohort study of 135 patients who had undergone OWHTO with an average of 52 months of follow-up.…”

“…In addition, the patellofemoral joint on the sagittal plane is also influenced by the operation [2]. Several studies have shown that OWHTO causes patellar infera, increases patellofemoral joint pressure pain, increases the risk of patellofemoral OA progression, and makes it more difficult for total knee arthroplasty to be performed in the future [3][4][5][6][7][8]. Kim et al [8] reported the prevalence of the progression of patellofemoral OA to be 41.2% in the femoral trochlea and 21.9% in the patella articular surface after more than 2 years in 114 patients who underwent OWHTO.…”

The Effect of Distal Tibial Tuberosity High Tibial Osteotomy on Postoperative Patellar Height and Patellofemoral Joint Degeneration

“…In many studies, the correction angle of the weightbearing line in OWHTO is considered to be related to the change in patella height and the deterioration of the patellofemoral joint. Otsuki et al [4] found that for every 1° increase in the correction angle, the CDI decreased by 1.7%, and CDI < 0.8 was a risk factor for the occurrence of a low patella after surgery. Yoon [2] et al conducted a cohort study of 135 patients who had undergone OWHTO with an average of 52 months of follow-up.…”

“…In addition, the patellofemoral joint on the sagittal plane is also in uenced by the operation [2] . Several studies have shown that OWHTO causes patella infra, increases patellofemoral joint pressure pain, increases the risk of patellofemoral OA progression, and makes it more di cult for total knee arthroplasty to be performed in the future [3][4][5][6][7][8] . Kim et al [8] reported the prevalence of the progression of patellofemoral OA to be 41.2% in the femoral trochlea and 21.9% in the patella articular surface after more than 2 years in 114 patients who underwent OWHTO.…”

A Novel Rat Model of Patellofemoral Osteoarthritis Due to Patella Baja, or Low-Lying Patella

“…The pathogenesis of PFJOA is linked to abnormal patellar kinematics, which catalyzes its initiation. Patella baja is defined as a short patellar tendon and is often caused by complex regional pain syndrome [59], trauma, immobilization or surgical procedures such as an opening wedge high tibial osteotomy [60]. Patellar misalignment caused by patella baja changes the patellofemoral contact pressure, increasing the joint reactive forces on both the patella and trochlea.…”