2017 ISAKOS Biennial Congress ePoster #1517

 

Effect of Concomitant Lateral Retinacular Release on Patellofemoral Alignment Following Opening Wedge High Tibial Osteotomy

Kazuhiro Murayama, MD, Nishinomiya, Hyogo JAPAN
Hiroshi Nakayama, MD, Nishinomiya, Hyogo JAPAN
Tomoya Iseki, MD. PhD., Nishinomiya, Hyogo JAPAN
Ryo Kanto, MD, Nishinomiya, Hyogo JAPAN
Tomohiko Murakami, MD, Osaka JAPAN
Shinichi Yoshiya, MD, Nishinomiya, Hyogo, Hyogo JAPAN
Shuhei Otsuki, MD, PhD, Takatsuki, Osaka JAPAN

Hyogo College of Medicine., Nishinomiya, Hyogo, JAPAN

FDA Status Cleared

Summary

Patellofemoral malalignment including patella baja is one of the complications after opening wedge high tibial osteotomy. This study compared the patellofemoral alignment following opening wedge high tibial osteotomy with and without concomitant lateral retinacular release. Radiological evaluation showed that lateral patellar tilt and shift could be corrected by concomitant lateral release.

Abstract

Purpose

Patellofemoral malalignment including patella baja is one of the complications after opening wedge high tibial osteotomy (OWHTO). This complication can be associated with functional problems such as decreased range of motion, impaired extensor strength due to reduced lever arm, anterior knee pain, and patellofemoral osteoarthritis as a sequel to joint overload. The purpose of this study was to examine whether the concomitant arthroscopic lateral retinacular release (LR) during OWHTO procedure can reduce the incidence of postoperative patellofemoral malalignment and associated patellofemoral problems.

Method

The study population comprised of 19 knees undergoing OWHTO with LR and 18 knees with OWHTO without LR as a control group. The patient characteristics in the control group was matched to those in the OWHTO/LR group except for age. The opening height at the osteotomy was more than 10 mm in all included patients. As for the radiographic evaluation, bilateral standing long leg view with hips, knees and ankles; weight-bearing anterior-posterior and true lateral views of the knee; and skyline view were obtained for evaluation in the preoperative period and at one year after surgery. Postoperative rehabilitation was same in these two groups.
Radiological parameters for patellofemoral alignment evaluated in this study were patella tilting angle (PTA), patella lateral shift (PLS), Insall-Salvati index (ISI), Modified Insall-Salvati index (M-ISI), Caton-Deschamps index (CDI), Blackburne-Peel index (BPI), tibial posterior slope (TS) and patellar-femur joint distance (Lateral side; L-PFD and Medial side; M-PFD). Differences between the groups and between the pre- and postoperative results were statistically analyzed using the Student t-test.
[Result] Comparison of pre- and postoperative radiological parameters in OWHTO with LR group demonstrated significant reduction in BPI, PTA, and PLS values and significant increase in ISI (p<0.05), while no significant postoperative changes were observed for CDI, TS, PFD values. In the OWHTO without LR group, CDI value was significantly reduced after surgery (p<0.05), while no significant postoperative changes were demonstrated for the remaining parameters.

Discussion

In both groups, postoperative patella baja was observed; however, significant reductions in PTA and PLS observed after OWHTO with LR may indicate that concomitant LR can improve the mechanical environment at the patellofemoral joint leading to prevention of postoperative osteoarthritic progression. Although not statistically proven, there was an increase in lateral PFD with a decrease in medial PFD following OWHTO with LR, while such tendency was not observed for knees with OWHTO alone. These findings seem to show additional potential advantages of concomitant LR with improvement in patellofemoral spatial relationship.

Conclusion

Arthroscopic LR concomitant with OWHTO can help improve the patellofemoral alignment as evidenced by reduction in lateral patellar tilt and shift after surgery.