A Study of the Decision Status for the Lateral Retinacular Release based on Lateral Patellar Tilt Angle in Total Knee Arthroplasty: Related with Tourniquet Effect

ABSTRACT

PURPOSE: The pattern of patellar tracking is changed depending upon whether a tourniquet is operating or not. This study was performed to suggest the criteria of lateral retinacular release(LRR) in total knee arthroplasty(TKA) based on the lateral patellar tilt angle(LPTA). MATERIALS AND METHODS: In study 1, the LPTA was compared in 24 bilateral TKAs, one side was required LRR and performed LRR, but not required and not done LRR on the other side according to the patellar tracking status in deflating tourniquet. In the second prospective study, we performed LRR one side and not the other side intentionally in all 11 patients' knees(22 knees) those who were same situations that the patellar tracking was not good under the condition of operating tourniquet but tracking was improved after deflation of tourniquet. We compared LPTA in both studies with paired t-test of SPSS 11.0. RESULTS: The LPTA was average 4.86 degrees on the side of performed LRR and 4.83 degrees on the other side in 24 patients. There was no significant difference of LPTA between them(p=0.952) in study 1. And the LPTA was average 5.18 degrees on the side of underwent LRR based on the condition of operating tourniquet, 5.45 degree on other not LRR side knee. There were also no significant difference between them(p=0.829) in study 2. CONCLUSION: The incidence of LRR will be reduced with no detrimental effect on lateral patellar tilt angle when making decision of LRR based on the patellar tracking status in deflating tourniquet.