Postoperative mechanical axis linked with patellofemoral degenerative progression after high tibial osteotomy
Among patients who underwent opening-wedge high tibial osteotomy, postoperative mechanical axis, which may be the result of overcorrection, was linked to patellofemoral degenerative progression.
Researchers identified 86 patients (total of 98 knees) who underwent hardware removal with second-look arthroscopy 21.4 months after opening-wedge high tibial osteotomy performed with first-look arthroscopy. The mean follow-up was 49.8 months. Investigators evaluated predictive factors for patellofemoral degeneration which included demographics, preoperative and postoperative mechanical axis of the lower limb, tibial slope and modified Blackburne-Peel ratio. Based on their patellofemoral degenerative progression from first to second arthroscopy, patients were categorized into either a progression or non-progression group. Clinical outcomes were compared between the groups.
Results showed the most significant factor for progressive change in the patellofemoral joint was the postoperative mechanical axis. There were 28 knees with patellofemoral degenerative progression. The mean postoperative Kujala score was lower in the progression group compared with the non-progression group (60.5 vs. 72.3). The KOOS scale scores were also lower in the progression group vs. the non-progression group, with the exception of the symptom subscale. The mean postoperative mechanical axis corrected in progression group compared with the non-progression group was -5.1° vs. -2.4°. – by Monica Jaramillo
Disclosure: The study was supported by a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, funded by the Ministry of Health and Welfare, Republic of Korea, grant number HI15C242.