Accuracy of Implant Placement Utilizing Customized Patient Instrumentation in Total Knee Arthroplasty

Customized patient instrumentation (CPI) combines preoperative planning with customized cutting jigs to position and align implants during total knee arthroplasty (TKA). We compared postoperative implant alignment of patients undergoing surgery with CPI to traditional TKA instrumentation for accuracy of implant placement. Twenty-five consecutive TKAs using CPI were analyzed. Preoperative CT scans of the lower extremities were segmented using a computer program. Limb alignment and mechanical axis were computed. Virtual implantation of computer-aided design models was done. Postoperative coronal and sagittal view radiographs were obtained. Using 3D image-matching software, relative positions of femoral and tibial implants were determined. Twenty-five TKAs implanted using traditional instrumentation were also analyzed. For CPI, difference in alignment from the preoperative plan was calculated. In the CPI group, the mean absolute difference between the planned and actual femoral placements was 0.67° in the coronal plane and 1.2° in the sagittal plane. For tibial alignment, the mean absolute difference was 0.9° in the coronal plane and 1.3° in the sagittal plane. For traditional instrumentation, difference from ideal placement for the femur was 1.5° in the coronal plane and 2.3° in the sagittal plane. For the tibia, the difference was 1.8° in the coronal plane. CPI achieved accurate implant positioning and was superior to traditional TKA instrumentation

Anterior cruciate ligament reconstruction in a patient who has received systemic steroids for autoimmune disease

Background: An anterior cruciate ligament (ACL) reconstruction has become more common and the surgical morbidity has decreased, it has been performed not only in younger people to play sports but also middle-aged people, with satisfactory results. Therefore, some patients might have comorbidities for which they take medicines. Especially the medicines, such as systemic steroids, might influence the reconstructed ligament strength and durability. Case report: A 49-year-old woman who was taking oral steroids for autoimmune hepatitis suffered a spontaneous ACL injury. She complained of unstable symptoms in the knee despite initial conservative treatment. Then, she was treated operatively with autologous hamstring tendon grafts. Three years postoperatively, her knee remained stable with 1.8 mm side-to-side difference on a Kneelax arthrometer and with 1.6 mm on anterior stress radiographs. There was no rerupture or instability. Conclusion: The patient who had received systemic steroids for a long time recovered satisfactorily after the operation, with achievement of knee stability and possibility to prevent degenerative change in the knee joint. ACL reconstruction should be considered even in patients with such medication

Tibial sagittal and rotational alignment reduce patellofemoral stresses in posterior stabilized total knee arthroplasty

Abstract Patellofemoral joint complications remain an important issue in total knee arthroplasty. We compared the patellofemoral contact status between cruciate-retaining and posterior-stabilized designs with varying degrees of tibial sagittal and rotational alignment using a computer simulation to ensure proper alignments in total knee arthroplasty. Knee kinematics, patellofemoral contact force and quadriceps force were computed using a musculoskeletal modeling program (LifeMOD/KneeSIM 2010; LifeModeler, Inc., San Clemente, California) during a weight-bearing deep knee bend. Two different posterior tibial slope (PTS)s (3° and 7°) and five different tibial tray rotational alignments (neutral, internal 5° and 10°, and external 5° and 10°) were simulated. Patellofemoral contact area and stresses were next computed using finite element analysis. The patellofemoral contact force for the posterior-stabilized design was substantially lower than the cruciate-retaining design after post-cam contact because of increasing femoral roll-back. Neutral rotational alignment of the tibial component resulted in smaller differences in patellofemoral contact stresses between cruciate-retaining and posterior-stabilized designs for PTSs of 3° or 7°. However, the patellar contact stresses in the cruciate-retaining design were greater than those in posterior-stabilized design at 120° of knee flexion with PTS of 3° combined with internal rotation of the tibial component. Our study provides biomechanical evidence implicating lower PTSs combined with internal malrotation of the tibial component and the resultant increase in patellofemoral stresses as a potential source of anterior knee pain in cruciate-retaining design

Metatarsalgia After Hallux Valgus Correction is Associated with Relative First Metatarsal Length

Category: Midfoot/Forefoot Introduction/Purpose: Metatarsalgia of the lesser metatarsal heads are frequently associated with hallux valgus. The aim of this study was to evaluate how the relative length and the position of the first metatarsal head influences the prognosis of metatarsalgia and plantar callosities beneath the lessor metatarsal heads. Methods: A retrospective analysis of the clinical data and radiographs of 102 cases was performed at a mean follow-up period of 16 months after biplane interlocking osteotomies. Clinical evaluation was made using the Japanese Society for Surgery of the Foot (JSSF) hallux scale. Radiological evaluation was made with standard weight-bearing AP radiographs, and the hallux valgus angle (HVA), inter-metatarsal 1-2 angle (IMA), distal metatarsal articular angulation (DMAA), and the sesamoid position were evaluated. Relative first metatarsal length (RML) was determined according to Nilsonne/Morton’s technique. Results: The mean preoperative HVA decreased from 37 to 3 degrees, and the mean IMA from 17 to 4 degrees. The mean JSSF- hallux score improved from 56 to 96 points. The mean preoperative area of plantar callosities decreased from 3.1 to 1.5 mm2. Sixty percent of metatarsalgia improved, and 85% of painless callosities disappeared postoperatively. Among radiological parameters, postoperative RML was most significantly associated with JSSF score (P < .0001) and the presence of postoperative metatarsalgia (P < .0001). ROC analysis revealed that the RML cut-off point was -3 mm for avoiding metatarsalgia, with an area under the curve of 0.884, a specificity of 88%, and a sensitivity of 85%. Conclusion: Preservation of RML during first metatarsal osteotomy is important to prevent postoperative metatarsalgia

Anatomic Reconstruction of Lateral Ankle Ligaments and Both Peroneus Tendons After Open Fracture Dislocation of the Ankle: A Case Report

Extensive soft tissue defects of the ankle are an uncommon but challenging problem that require a combination of reconstructive options. We report the case of a complex injury involving the skin, lateral ankle ligaments, and peroneal tendons that were anatomically reconstructed. A 15-year-old girl was injured in an automobile accident resulting in extensive soft tissue defects and marked instability of her right ankle. The lower two-thirds of the anterior talofibular ligament (ATFL) had segmental defects, and calcaneofibular ligament (CFL) was completely torn, and both peroneal longus and brevis tendons were severely damaged. Initial debridement was performed on the day on injury. Two weeks after injury, the ATFL and CFL were reconstructed using a semitendinosus autograft and suture tape augmentation. Both peroneal tendons were reconstructed using a gracilis autograft. The skin defect (10 × 10 cm) was covered with an anterolateral thigh flap. After removing a short leg cast at 3 weeks postoperatively, the patient started range of motion exercises without using any brace. Weightbearing was allowed at 4 weeks. At the 24-month follow-up examination, she had returned to her preoperative level of work and sports activities

Distal Tibial Tuberosity Arc Osteotomy in Open-Wedge Proximal Tibial Osteotomy to Prevent Patella Infra

Open-wedge high tibial osteotomy is considered to be an effective surgical intervention for medial compartmental knee osteoarthritis. However, patella infra, which has been reported to be a result of tuberosity distalization after open-wedge high tibial osteotomy, changes the native patellofemoral biomechanics. This could raise abnormal patellofemoral contact stresses, which might be the trigger of patellofemoral arthrosis. To minimize the reduction in patellar height, we have developed a technique called open-wedge distal tuberosity tibial osteotomy. The benefits of this technique include increased bone-to-bone contact of the distal tuberosity cut surface after correction by cutting an arc osteotomy around the hinge position, which is the center of rotation. This technique also provides cortical support at the anterior osteotomy site without additional bone defect and, therefore, may be advantageous against weight-bearing stress on the osteotomy site. In all, open-wedge distal tuberosity tibial osteotomy could potentially be a unique open-wedge osteotomy that eliminates the risk for postoperative patellofemoral osteoarthritis and also could theoretically encourage rapid healing of the osteotomy, which could lead to early return to full physical activity