199 Use of A 3D Hand-Held Scanner to Capture Trochlear Groove Shape, A Proof-of-Concept Study

Introduction Trochleoplasty is a surgical procedure used to treat patellar instability through modifying the trochlear groove. Analysis of the groove with a hand-held scanner would enable accurate real time planning and facilitate tailor made correction. We aimed to measure trochlear depth, sulcus angle, trochlear facet ratio, trochlear angle and lateral trochlear inclination angle and establish inter- and intra-rater reliability for each knee model. Method The trochlear groove of the knee models was scanned by two investigators and 3D reference models created. These were surface matched and custom software along with Excel was utilised to determine the desired parameters. Intraclass correlation coefficient (ICC) was used for test-retest reliability and to determine which parameter results, for each model, showed the best reproducibility. Results There was good inter-observer reliability - trochlear depth (1.0 mm), sulcus angle (2.7°), trochlear angle (4.0°) and lateral trochlear inclination angle (4.0°), except in the trochlear facet ratio (32.0%) of one knee model. With outliers removed ICC was good-excellent in (46.7%) of measurements, with trochlear depth showing the best reproducibility. Conclusions This feasibility study showed that the hand-held scanner in conjunction with supporting software can measure trochlear parameters in a controlled environment and justifies extending research into its use in trochleoplasty.

Joint hemorrhage accelerates cartilage degeneration in a rat immobilized knee model

Background Joint hemorrhage is caused by trauma, ligament reconstruction surgery, and bleeding disorders such as hemophilia. Recurrence of hemorrhage in the joint space induces hemosiderotic synovitis and oxidative stress, resulting in both articular cartilage degeneration and arthropathy. Joint immobilization is a common treatment option for articular fractures accompanied by joint hemorrhage. Although joint hemorrhage has negative effects on the articular cartilage, there is no consensus on whether a reduction in joint hemorrhage would effectively prevent articular cartilage degeneration. The purpose of this study was to investigate the effect of joint hemorrhage combined with joint immobilization on articular cartilage degeneration in a rat immobilized knee model. Methods The knee joints of adult male rats were immobilized at the flexion using an internal fixator from 3 days to 8 weeks. The rats were randomly divided into the following groups: immobilized blood injection (Im-B) and immobilized-normal saline injection (Im-NS) groups. The cartilage was evaluated in two areas (contact and non-contact areas). The cartilage was used to assess chondrocyte count, Modified Mankin score, and cartilage thickness. The total RNA was extracted from the cartilage in both areas, and the expression of metalloproteinase (MMP)-8, MMP-13, interleukin (IL)-1β, and tumor necrosis factor (TNF)-α was measured by quantitative real-time polymerase chain reaction. Results The number of chondrocytes in the Im-B group significantly decreased in both areas, compared with that in the Im-NS group. Modified Mankin score from 4 to 8 weeks of the Im-B group was significantly higher than that of the Im-NS group only in the contact area. The expression of MMP-8 and MMP-13 from 2 to 4 weeks and TNF-α from 2 to 8 weeks significantly increased in the Im-B group compared with those in the Im-NS group, but there was no significant difference in IL-1β expression. Conclusions The results showed that joint hemorrhage exacerbated immobilization-induced articular cartilage degeneration. Drainage of a joint hemorrhage or avoidance of loading may help prevent cartilage degeneration during joint immobilization with a hemorrhage.

Joint hemorrhage accelerates cartilage degeneration in a rat immobilized knee model

Background: Joint hemorrhage is caused by trauma, ligament reconstruction surgery, and bleeding disorders such as hemophilia. Recurrence of hemorrhage in the joint space induces hemosiderotic synovitis and oxidative stress, resulting in both articular cartilage degeneration and arthropathy. Joint immobilization is a common treatment option for articular fractures accompanied by joint hemorrhage. Although joint hemorrhage has negative effects on the articular cartilage, there is no consensus on whether a reduction in joint hemorrhage would effectively prevent articular cartilage degeneration. The purpose of this study was to investigate the effect of joint hemorrhage combined with joint immobilization on articular cartilage degeneration in a rat immobilized knee model.Methods: The knee joints of adult male rats were immobilized at the flexion using an internal fixator from 3 days to 8 weeks. The rats were randomly divided into the following groups: immobilized blood injection (Im-B) and immobilized-normal saline injection (Im-NS) groups. The cartilage was evaluated in two areas (contact and non-contact areas). The cartilage was used to assess chondrocyte count, Modified Mankin score, and cartilage thickness. The total RNA was extracted from the cartilage in both areas, and the expression of metalloproteinase (MMP)-8, MMP-13, interleukin (IL)-1β, and tumor necrosis factor (TNF)-α was measured by quantitative real-time polymerase chain reaction.Results: The number of chondrocytes in the Im-B group significantly decreased in both areas, compared with that in the Im-NS group. Modified Mankin score from 4–8 weeks of the Im-B group was significantly higher than that of the Im-NS group only in the contact area. The expression of MMP-8 and MMP-13 from 2 to 4 weeks and TNF-α from 2 to 8 weeks significantly increased in the Im-B group compared with those in the Im-NS group, but there was no significant difference in IL-1β expression.Conclusions: The results showed that joint hemorrhage exacerbated immobilization-induced articular cartilage degeneration. Drainage of a joint hemorrhage or avoidance of loading may help prevent cartilage degeneration during joint immobilization with a hemorrhage.