2017 ISAKOS Biennial Congress ePoster #1244

 

Effects of Suture and Tourniquet on Intraoperative Kinematics in Navigated Total Knee Arthroplasty

Masanori Tsubosaka, MD, Kobe, Hyogo JAPAN
Kazunari Ishida, MD, PhD, Kobe, Hyogo JAPAN
Hiroshi Sasaki, MD, PhD, Kobe JAPAN
Nao Shibanuma, MD, Kobe, Hyogo JAPAN
Ryosuke Kuroda, MD, PhD, Kobe, Hyogo JAPAN
Tomoyuki Matsumoto, MD, PhD, Kobe, Hyogo JAPAN

Kobe Kaisei Hospital, Kobe, Hyogo, JAPAN

FDA Status Not Applicable

Summary

We evaluated the suture and tourniquet effects on kinematics during TKA surgery and found that the intraoperative kinematics can effectively evaluate the postoperative passive kinematic conditions, thus, the assessment of intraoperative kinematics is useful to evaluate and improve the postoperative conditions, leading to improve the postoperative clinical outcomes after TKA.

Abstract

Purpose

The present study aimed to investigate the effects of suture on the joint capsule (1) and of tourniquet use (2) on intraoperative kinematics in computed tomography (CT)-based navigated total knee arthroplasty (TKA). It is hypothesized that the effects of suture and tourniquet on passive motion kinematics is minimal and the intraoperative kinematics at post-implantation is useful evaluation to be regarded as postoperative passive knee kinematics.

Materials And Methods

The study included 20 patients (18 female and 2 male patients) with varus-type knee osteoarthritis who underwent primary posterior-stabilized TKA. The operation was performed by one experienced surgeon with a medial parapatellar approach and the measured resection technique using a CT-based navigation system. All the surgeries were performed using air tourniquet (300mmHg) prior to skin incision. Intraoperative tibiofemoral kinematics from maximum extension up to maximum flexion were measured using the navigation. The timing of the measurements was as follows; measurement 1: before suture (tourniquet on), measurement 2: after suture (tourniquet on), and measurement 3: after tourniquet off. Measured items were i) knee joint gap, ii) tibiofemoral rotational angles, and iii) antero-posterior (AP) distance between femur and tibia. Knee joint gaps were defined as the distance between the cut bone surface of femur and tibia. Knee joint gaps were measured on the medial and lateral tibiofemoral joint at maximum extension and 90° of flexion, respectively. Tibiofemoral rotational angles were defined as the angle between the perpendicular line of the surgical epicondylar axis and Akagi‚Äôs line. AP distance was defined as the distance in the longitudinal direction between the distal end of femoral mechanical axis and the proximal end of tibial mechanical axis. These measured items were compared among the three measurements and statistically evaluated.

Results

At medial side, there was no significant difference among the three measurements in the extension gap, but measurement 1 showed significant larger flexion gap compared to the other two measurements (p < 0.05). On the other hand, at lateral side, there were no significant differences between the extension and flexion gaps in all measurements. The results with AP distance revealed that femur significantly positioned more anterior to tibia in measurement 1, compared to the other two groups at 10° and 20° of flexion (p < 0.05). There was no significant difference among the three measurements in the amount of tibiofemoral rotation angles.

Conclusion

We evaluated the suture and tourniquet effects on kinematics during TKA surgery. The femur positioned more anterior to tibia in mid-flexion from extension before suture. The medial flexion gap before suture was significantly larger than that after suture. There was no significant effect on the kinematics due to the tourniquet. These results suggested that the intraoperative kinematics can effectively evaluate the postoperative passive kinematic conditions, thus, the assessment of intraoperative kinematics is useful to evaluate and improve the postoperative conditions, leading to improve the postoperative clinical outcomes after TKA.