Computer-aided Surgical Planning of Anterior Cruciate Ligament Reconstruction in MR Images

AbstractAnterior cruciate ligament (ACL) injury causes knee joint instability, and effects on sports performance. Therefore, ACL reconstruction is essential to keep their high performance. It is well known that the outcome of ACL reconstruction is strongly related to the placement and orientation of the bone tunnel. Therefore, optimization of tunnel drilling technique is an important factor to obtain satisfactory surgical results. Current procedure relies on arthroscopic evaluation and there is a risk of damaging arteries and ligaments during surgery. The damages may reduce the accuracy and reproducibility of ACL reconstruction. As a postoperative evaluation method, a quadrant method has been used to evaluate the placement and orientation of the bone tunnel in X-ray radiography. This study proposes a computer-aided surgical planning system for evaluating ACL insertion site and orientation using magnetic resonance (MR) images. We first introduce MR image based the quadrant method to determine the ACL insertion site for preoperative patients. It also evaluates the 3-D spatial relationship between the planning femoral drilling hole and arteries around the femoral condyle. This system has been applied to ACL injured patients, it may increase the accuracy and reproducibility of ACL bone tunnel, and it can evaluate a risk of damaging the surrounding arteries and ligaments

Persistent Hemarthrosis of the Knee after Arthroscopic Meniscal Repair

Introduction. In this case report, we report a patient with complicated with persistent hemarthrosis following arthroscopic meniscal repair. Case Presentation. A 41-year-old male patient presented with persistent swelling of the knee 6 months after arthroscopic meniscal repair and partial meniscectomy performed for lateral discoid meniscal tear. The initial surgery was performed at another hospital. Four months after the surgery, swelling of the knee was noted when he resumed running. At his initial visit to our hospital, intra-articular blood accumulation was revealed via joint aspiration. A second arthroscopic examination performed 7 months after the initial procedure showed healing of the meniscal repair site and synovial proliferation. The suture materials identified during the arthroscopy were removed. Histological examination of the resected synovial tissue showed inflammatory cell infiltration and neovascularization. In addition, a multinucleated giant cell was identified in the superficial layer. After the second arthroscopic surgery, the hemarthrosis did not recur, and the patient was able to resume running without symptom one and a half years post-surgery. Conclusion. Bleeding from the proliferated synovia at or near the periphery of the lateral meniscus was thought to be the cause of the hemarthrosis as a rare complication following arthroscopic meniscal repair

Three dimensional CT analysis of the change in rotational alignment in double level osteotomy after double level osteotomy performed for varus osteoarthritic knees

Purpose: To analyze the change in rotational alignment caused by double level osteotomy (DLO) based on comparative three-dimensional image analysis of pre- and postoperative CT images. Methods: Pre- and postoperative CT examination of the lower extremities were performed with informed consent for 39 consecutive knees undergoing DLO for varus knee deformity. The DLO procedure consisted of closed wedge distal femoral osteotomy (CWDFO) and open wedge high tibial osteotomy (OWHTO). Among those cases, 20 knees complicated with hinge fracture at the osteotomy site were excluded from the analysis to eliminate a confounding factor affecting the results. Consequently, data obtained from 19 knees were subjected to the study analysis while osteotomies with hinge fractures complications were excluded from the study. In the three-dimensional CT image analysis of axial plane images, femoral torsion (the angle between midline along the femoral neck axis and the tangent of the posterior edges of the medial/lateral femoral condyles) and tibial torsion (the angle between the tangent of the posterior edges of the medial/lateral tibial condyles and the transmalleolar axis) were measured. The torsion angle was measured in each of the femurs and the tibias on both pre- and postoperative CT axial images, and the change induced by the osteotomy was calculated and statistically(using Wilcoxon signed-rank test) compared. Results: The mean pre- and postoperative femoral torsion (anteversion) angles were 29.3° and 31.4° with a significant postoperative increase in internal rotation of the bony segment distal to the osteotomy(P = 0.002). On the tibial side, the mean pre- and postoperative torsion angles were 26.5° and 25.7°, indicating no significant postoperative change(P = 0.199)（NS）. Conclusions: This study showed that the DLO procedure (combining CWDFO and OWHTO) increased torsion (anteversion) of the femur by 2.1° on average while inducing no significant rotational change on the tibial side

Clinical outcome of meniscus repair for isolated meniscus tear in athletes

Objective: To examine the clinical and functional outcomes for a series of patients who underwent meniscal repair for isolated meniscal tears focusing the study population on athletes. Methods: This study represents a case series of 46 athletes who underwent repair of isolated meniscal lesions of the knee from 2010 to 2015. Cases of discoid meniscal lesions and combined ligament injuries were excluded. The mean age of the patients was 22.9 years ranging from 12 to 50 years. Arthroscopic inside-out repair was primarily a procedure of option. For repair of tears with degeneration and inferior vascularity, autogenous fibrin clot was implanted to the repair site for healing enhancement. The mean follow-up period of all patients was 19.8 ± 6.8 months (range; 12 months–33 months). Results: In total, 37 of 46 patients (80%) could go back to their original sports activities. During the follow-up period, re-tear was encountered in 4 of 46 knees (8.7%). No significant differences in clinical/functional outcomes and re-tear rate were detected between the medial and lateral meniscal repairs. Conclusion: In our expanded repair indication for isolated meniscus repair for athletes, the rate of satisfactory return to sports was 91.3% in total (88.9% for the medial meniscus group; 92.9% for the lateral meniscus group). During the follow-up period ranging from 12 to 33 months (mean, 19.8 months), re-tear of the repaired site was encountered in 4 of the 46 knees (8.7%)