Takaki Sanada

Remnant-Preserving Anterior Cruciate Ligament Reconstruction Using a Three-Dimensional Fluoroscopic Navigation System

Introduction Recently, remnant-preserving anterior cruciate ligament (ACL) reconstruction has been increasingly performed to achieve revascularization, cell proliferation, and recovery of high-quality proprioception. However, poor arthroscopic visualization makes accurate socket placement during remnant-preserving ACL reconstruction difficult. This study describes a surgical technique used to create an anatomical femoral socket with a three-dimensional (3D) fluoroscopy based navigation system during technically demanding remnant-preserving ACL reconstruction. Surgical Technique After a reference frame was attached to the femur, an intraoperative image of the distal femur was obtained, transferred to the navigation system and reconstructed into a 3D image. A navigation computer helped the surgeon visualize the entire lateral wall of the femoral notch and lateral intercondylar ridge, even when the remnant of the ruptured ACL impeded arthroscopic visualization of the bone surface. When a guide was placed, the virtual femoral tunnel overlapped the reconstructed 3D image in real time; therefore, only minimal soft tissue debridement was required. Materials and Methods We treated 47 patients with remnant-preserving ACL reconstruction using this system. The center of the femoral socket aperture was calculated according to the quadrant technique using 3D computed tomography imaging. Results The femoral socket locations were considered to be an anatomical footprint in accordance with previous cadaveric studies. Conclusions The 3D fluoroscopy-based navigation can assist surgeons in creating anatomical femoral sockets during remnant-preserving ACL reconstruction.

Iliotibial band irritation caused by the EndoButton after anatomic double-bundle anterior cruciate ligament reconstruction: report of two cases.

Two patients underwent arthroscopic anatomic double-bundle anterior cruciate ligament (ACL) reconstruction using the EndoButton for femoral fixation. The femoral tunnels were created by the inside-out technique through a far anteromedial portal. The patients postoperatively developed moderate lateral knee pain without instability. At the second-look arthroscopic evaluation, the two EndoButtons were removed. Both patients were completely asymptomatic several months after implant removal, implying that the EndoButtons caused the mechanical irritation in the iliotibial band. This is the first report describing removal of EndoButtons because of pain caused by friction with the iliotibial band. In anatomic ACL reconstruction, if the femoral tunnel exit is positioned near the lateral femoral epicondyle, care should be taken to prevent iliotibial band friction syndrome that could result because of the EndoButton.

An additional reference axis improves femoral rotation alignment in image-free computer navigation assisted total knee arthroplasty.

Few studies have demonstrated improvement in accuracy of rotational alignment using image-free navigation systems mainly due to the inconsistent registration of anatomical landmarks. We have used an image-free navigation for total knee arthroplasty, which adopts the average algorithm between two reference axes (transepicondylar axis and axis perpendicular to the Whiteside axis) for femoral component rotation control. We hypothesized that addition of another axis (condylar twisting axis measured on a preoperative radiograph) would improve the accuracy. One group using the average algorithm (double-axis group) was compared with the other group using another axis to confirm the accuracy of the average algorithm (triple-axis group). Femoral components were more accurately implanted for rotational alignment in the triple-axis group (ideal: triple-axis group 100%, double-axis group 82%, P<0.05).

Secure fixation of femoral bone plug with a suspensory button in anatomical anterior cruciate ligament reconstruction with bone-patellar tendon-bone graft.

PURPOSE the efficacy and safety of using a suspensory button for femoral fixation in anatomical anterior cruciate ligament (ACL) reconstruction with bone-patellar tendon-bone (BPTB) graft have not been established. The purpose of the current study was to evaluate bone plug integration onto the femoral socket and migration of the bone plug and the EndoButton (EB) (Smith & Nephew, Andover, MA, USA) after rectangular tunnel ACL reconstruction with BPTB autograft. METHODS thirty-four patients who underwent anatomical rectangular ACL reconstruction with BPTB graft using EB for femoral fixation and in whom three-dimensional (3D) computed tomography (CT) was performed one week and one year after surgery were included in this study. Bone plug integration onto the femoral socket, bone plug migration, soft tissue interposition, EB migration and EB rotation were evaluated on 3D CT. The clinical outcome was also assessed and correlated with the imaging outcomes. RESULTS the bone plug was integrated onto the femoral socket in all cases. The incidence of bone plug migration, soft tissue interposition, EB migration and EB rotation was 15, 15, 9 and 56%, respectively. No significant association was observed between the imaging outcomes. The postoperative mean Lysholm score was 97.1 ± 5.0 points. The postoperative side-to-side difference, evaluated using a KT-2000 arthrometer, averaged 0.5 ± 1.3 mm. There were no complications associated with EB use. Imaging outcomes did not affect the postoperative KT side-to-side difference. CONCLUSIONS the EB is considered a reliable device for femoral fixation in anatomical rectangular tunnel ACL reconstruction with BPTB autograft. LEVEL OF EVIDENCE Level IV, therapeutic case series.

Twice cutting method reduces tibial cutting error in unicompartmental knee arthroplasty

BACKGROUND Bone cutting error can be one of the causes of malalignment in unicompartmental knee arthroplasty (UKA). The amount of cutting error in total knee arthroplasty has been reported. However, none have investigated cutting error in UKA. The purpose of this study was to reveal the amount of cutting error in UKA when open cutting guide was used and clarify whether cutting the tibia horizontally twice using the same cutting guide reduced the cutting errors in UKA. METHODS We measured the alignment of the tibial cutting guides, the first-cut cutting surfaces and the second cut cutting surfaces using the navigation system in 50 UKAs. Cutting error was defined as the angular difference between the cutting guide and cutting surface. RESULTS The mean absolute first-cut cutting error was 1.9° (1.1° varus) in the coronal plane and 1.1° (0.6° anterior slope) in the sagittal plane, whereas the mean absolute second-cut cutting error was 1.1° (0.6° varus) in the coronal plane and 1.1° (0.4° anterior slope) in the sagittal plane. Cutting the tibia horizontally twice reduced the cutting errors in the coronal plane significantly (P<0.05). CONCLUSION Our study demonstrated that in UKA, cutting the tibia horizontally twice using the same cutting guide reduced cutting error in the coronal plane.

Gravity Equinus Position to Control the Tendon Length of Reversed Free Tendon Flap Reconstruction for Chronic Achilles Tendon Rupture

Abstract Repair of chronic Achilles tendon rupture is a surgical challenge. We describe the use of a free turndown tendon flap augmentation raised from the proximal gastrocnemius aponeurosis. To control optimal tension or the reconstructed Achilles tendon length, we used an original method by referring to the gravity planter flexion ankle angle of the contralateral limb. Key aspects of the technique are described. A retrospective analysis of the short‐term outcomes achieved in a case series (n = 56) is presented. The postoperative anthropometric findings are also presented to indicate the successful outcomes achieved with this technique. &NA; Level of Clinical Evidence: 4

Myositis ossificans after navigated knee surgery: A report of two cases and literature review

Computer-assisted surgery is now a common procedure in the field of orthopedics. We present two patients who developed myositis ossificans, a rare complication after navigated knee surgery. Due to careful follow-up and conservative treatment, surgical excision was avoided in both patients with good clinical results. Development of myositis ossificans after navigated knee surgery should be considered in cases of thigh pain and restricted range of motion of the knee.

Missed Medial Malleolar Fracture Associated With Achilles Tendon Rupture: A Case Report and Literature Review

A 45-year-old man sustained an Achilles tendon rupture while playing futsal. A concomitant medial malleolar fracture was not diagnosed until the patient underwent an operation for Achilles tendon repair. A routine postoperative radiograph showed a minimally displaced medial malleolar fracture. Conservative treatment was chosen for the fracture. The function of the Achilles tendon recovered well, and the fracture was united. A medial malleolar fracture can be missed when an Achilles tendon rupture occurs simultaneously. Thus, surgeons should consider the possibility of medial malleolar fracture associated with an Achilles tendon rupture.