As compared to the open wedge high tibial osteotomy (OWHTO), hybrid closed wedge HTO (HCWHTO) provides more effective outcomes in managing patellofemoral joint congruity, findings of a recently performed retrospective study by the investigators of Yokosuka Municipal Hospital, Fukuoka University Faculty of Medicine, and Murup Hospital.

The analysis involved an evaluation of to 21 knees of17 patients and 36 knees of 31 patients who went through HCWHTO and OWHTO, respectively. Radiological outcomes comprised preoperative PF osteoarthritis (OA) grade, medial and lateral joint spaces of the PF joint, femoral patellar height index (FPHI), hip–knee–ankle angle (HKA), and congruence angle were estimated. The Oxford Knee Score (OKS) and the Knee injury and Osteoarthritis Outcome Score (KOOS) were considered as the clinical parameters. Outcome analyses compared the preoperative and final follow-up values for all procedure.

The patients treated with HCWHTO showed severe mean preoperative HKA and the degree of PF-OA as compared to the patients treated with OWHTO. HCWHTO significantly reduced the mean postoperative FPHI with proximalization of the patella, whereas OWHTO was unable to present notable changes. Also, significant improvements were noticed in lateral joint space and congruence angle with HCWHTO treatment. With OWHTO treatment, no notable difference was seen within the congruence angle, but lateral and medial joint spaces were significantly reduced. No difference was seen in OKS and KOOS between the groups.

Although, HCWHTO group found to have severe degrees of varus knee and PF-OA as compared to OWHTO, but led to improving PF joint congruity and shows similar mid-term clinical outcomes as of OWHTO.