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A large posterior tibial slope (PTS) has been widely recognized as a potential risk factor in loosening and retear after anterior cruciate ligament reconstruction. Anterior closed-wedge osteotomy is an effective surgical approach to mitigate this risk factor but presents several disadvantages. We describe in this Technical Note an original PTS correction technique called the posterior open-wedge osteotomy. The posterior surface of the proximal tibia is exposed, and 2 K-wires are inserted anteroposteriorly as osteotomy guides, and one wire is inserted mediolaterally as a hinge blocker. The osteotomy is performed from the posterior side and advanced to the anterior side using a single-bladed reciprocating saw. The slope is corrected by opening the osteotomy plane posteriorly with a spreader. The correction is maintained by inserting the harvested fibula fragments into the open space, and the fixation is completed with a locking plate to ensure firm fixation and allow early rehabilitation. This procedure can be an effective solution for patients with various risk factors for retear of the anterior cruciate ligament graft, including abnormal PTS. [Display omitted] [ABSTRACT FROM AUTHOR]

Ultra-high molecular weight polyethylene sutures are used for repair and reconstruction of extra-articular ligaments in the knee, elbow, and ankle joints. In recent years, the use of these sutures has become popular in a suture augmentation technique and has been applied for use in the reconstruction of the anterior cruciate ligament, which is an intra-articular ligament. Although several surgical techniques have been described in Technical Notes, all reports have been for single-bundle reconstruction, and none have applied the technique to double-bundle reconstruction. This Technical Note provides a detailed description of an anatomical double-bundle anterior cruciate ligament reconstruction combined with the suture augmentation technique. [Display omitted] [ABSTRACT FROM AUTHOR]

To evaluate the initial safety of the combined use of ultra-high molecular weight polyethylene (UHMWPE) sutures for suture augmentation (SA) in a porcine ACL reconstruction model and examine whether the procedure can affect the anterior knee laxity and structural properties of the tendon graft itself, influence histological remodeling, and cause a foreign body-induced inflammation. Ten pigs were divided into SA and non-SA Groups to undergo ACL reconstruction using an autologous semitendinosus tendon with and without SA, respectively. At 12 weeks postoperatively, the tibial fixation of the grafted tendon and SA was removed, and the anterior knee laxity and structural characteristics of the grafted tendon were evaluated for mechanical testing. Histological evaluation, including the ligament tissue maturation index (LTMI) score and the presence or absence of foreign-body reaction, was evaluated. There was no significant difference in anterior laxity between the two groups (SA Group, 1.19 ± 0.78 mm; non-SA Group, 1.08 ± 0.42 mm; P = 1). There were no significant differences in maximum load failure, yield strength, stiffness, elongation at failure, and the LTMI score between the two groups (P = 0.31, 1, 1, 1, and 0.24, respectively). All grafted tendons showed no foreign-body reactions. Suture augmentation did not have significant effect on the anterior knee laxity and the structural properties of the grafted tendon, interfere with histological remodeling, or cause foreign body-induced reactions. The results of our study may lay the foundation for further clinical studies to verify the usefulness of ACL reconstruction with SA. [ABSTRACT FROM AUTHOR]

The menisci have a poor intrinsic healing capability. Biological augmentation is used to promote meniscal healing in conjunction with suture techniques as the result of their poor healing rate. A fibrin clot (FC) is a well-known treatment option for meniscal injuries that are difficult to heal. Several methods for delivering FCs to target sites have been reported; however, all available methods have drawbacks such as unstable delivery, low maneuverability, and/or clot sizes that are too large. We use a dedicated device to efficiently deliver FCs of a suitable size for the tear. In this method, an FC formed to a size of 5 mm is stored and delivered in a thin syringe with a built-in plunger. This method enables an accurate delivery of a suitably sized FC to the desired location and fixes FCs to the tear site when used in combination with conventional suture methods. In this report, we will succinctly describe how to make and deliver an FC using the aforementioned device with a step-by-step instructional technique and an illustrative video. [Display omitted] [ABSTRACT FROM AUTHOR]

Recent studies on the detailed anatomy of the medial patellar stabilizer have revealed that the medial patellofemoral ligament (MPFL) not only attaches to the patella but also has fibers that attach to the quadriceps muscle, known as the medial quadriceps tendon femoral ligament (MQTFL). Reconstruction of the medial stabilizer for patellar dislocation that includes both the MPFL and MQTFL may achieve better anatomical and physiological correction. In this Technical Note, we will describe a simultaneous reconstruction technique of the MPFL and MQTFL for patellar dislocation using an artificial ligament. [Display omitted] [ABSTRACT FROM AUTHOR]

Anterior cruciate ligament (ACL) remnant preservation techniques have been recently introduced for covering the graft with remnant to improve the clinical results of ACL reconstruction. Several theoretical advantages exist for this technique; however, clinical results remain inconsistent and controversial. We have focused on the biomechanical function of the remnant and have been performing a new remnant-preserving reconstruction procedure that augments the graft with residual remnant. Preserving the structure and continuity of good-quality remnants may help maintain the early postoperative stress on the tendon graft, thereby providing a positive effect on remodeling. Although our concept is significantly different from previously reported remnant preservation techniques and has several pitfalls, the surgical technique that we outline in this report is simple and does not require specialized equipment. The procedure will also work more advantageously in preserving the residual mechanoreceptors in the remnant. We believe that this method can be a procedure with better results for patients with remnants that are in good condition. [ABSTRACT FROM AUTHOR]

Purpose: To assess (1) if 6 anatomic landmarks (ALs) could be arthroscopically confirmed with remnant preservation and (2) if creating tibial tunnels using these landmarks reduces individual variation and improves reproducibility in double-bundle anterior cruciate ligament (ACL) reconstruction.Methods: We retrospectively reviewed data of patients who chronologically underwent double-bundle ACL reconstruction by either referencing the footprint after remnant dissection (non-AL group) or subsequently with the ALs (AL group). Using operative videos, 3 independent observers judged whether they could confirm 6 ALs (medial intercondylar ridge, medial and lateral intercondylar tubercles, anterior horn of lateral meniscus, Parsons' knob, and L-shaped ridge) in 20 patients randomly selected from the AL group. We then compared tunnel positions between the 2 groups, measured from the anterior and medial borders of the proximal tibia and expressed as percentage of the total depth and width of the proximal tibia using 3-dimensional computed tomography.Results: One hundred four patients (non-AL group, n = 54; AL group, n = 50) were included. All 6 ALs were arthroscopically confirmed in most cases (89.7% to 100%). The mean percentages of the anteroposterior (AP) depth for anteromedial (AM) tunnel, mediolateral (ML) width for AM tunnel, AP depth for posterolateral (PL) tunnel, and ML width for PL tunnel, respectively, were 27.8% ± 6.6%, 46.7% ± 2.8%, 41.4% ± 7.3%, and 46.1% ± 2.6% for the non-AL group and 30.7% ± 4.5%, 45.7% ± 2.2%, 45.2% ± 4.5%, and 46.9% ± 2.1% for the AL group, revealing significantly less variation in the AL group compared with the non-AL group, excluding the ML width of the PL tunnel (P = .007, .046, .002, .209, respectively).Conclusions: Six landmarks could be reliably confirmed in cases with remnant preservation, and creating tibial tunnels using these landmarks were reproducible and resulted in less individual variation.Level Of Evidence: Level III, retrospective comparative study. [ABSTRACT FROM AUTHOR]

The linear penetration rates for ceramic femoral heads on conventional and highly cross-linked polyethylene were measured and compared with radiographs taken in the standing and supine position taken three weeks postoperatively and at final follow-up. Seventy-five patients (83 hips) with conventional polyethylene (group-1) and two hundred and seventy five patients (300 hips) with highly cross-linked polyethylene (group-2) were studied. Follow-up periods were 14.5 years in group-1 and 8.6 years in group-2. The average penetration rates in group-1 were 0.17 mm/year in supine position and 0.18 mm/year in standing position ( P < 0.05). On the other hand, the rates in group-2 were 0.03 mm/year and 0.04 mm/year respectively ( P < 0.05). Although there were statistical differences between groups, 0.01 mm differences are probably not clinically relevant. [ABSTRACT FROM AUTHOR]

Background: Aiming to construct an osteochondral-like structure, the combination of a β-tricalcium phosphate (βTCP) block with a scaffold-free sheet formed using mesenchymal stem cells (MSCs) was investigated. Methods: Human bone marrow MSCs in a cell culture insert that was set in a 24-well plate were cultivated using a chondrogenic medium containing dexamethasone, IGF-1, and TGFβ3 for 3 weeks during which a cylindrical βTCP block was put on the sheet at day 1, and the cell sheet construct was harvested. In other experiments, at day 14, the construct was put on a cell sheet that was prepared the day before and cultivated for 3 weeks. Results: The addition of a βTCP block resulted in a combined osteochondral-like construct and comparable staining intensity by Alcian blue, while the expression levels of the aggrecan and type II collagen genes decreased a little. During the culture with the βTCP block, the expression levels of the aggrecan gene increased monotonically. The increase in the inoculum cell number from 1.86 to 3.72 × 10 cells resulted in marked increases in the thickness of cell sheet parts in the βTCP block and expression levels of the aggrecan and type II collagen genes, while the thickness of cell sheet parts on the βTCP block scarcely changed. On the other hand, the addition of a cell sheet that was prepared a day before to the construct at day 14 resulted in the marked increase in thickness of the cell sheet part on the βTCP block, while the thickness of that in the βTCP block did not increase. Conclusion: A combined osteochondral-like structure was produced by putting a βTCP block on the sheet of MSC. The thickness of the cell sheet parts in and on the βTCP block could be increased by the increase in inoculum cell number and by providing an additional cell sheet, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Fourteen hips in 14 patients (all female; average age, 64 years) with severe bone defects due to developmental dysplasia of the hip or migration of the socket were treated with hydroxyapatite block with impacted morselized bone graft in conjunction with a cemented socket. All patients were followed clinically in a prospective fashion, and radiographs were analyzed retrospectively. One initial patient had 17-year follow-up, whereas the remaining 13 patients had follow-up between 4 and 6.5 years. No acetabular components were revised, including the socket of a 17-year postoperative case that remains rigidly fixed and supported by the graft and hydroxyapatite block with only mild polyethylene wear and minor osteolysis. Osteointegration and good clinical outcome were achieved in all cases by reconstruction with this technique in total hip arthroplasty. [Copyright &y& Elsevier]

Abstract: To examine how fibroblast growth factor-2 (FGF-2) affects the BMP signaling pathway during bone morphogenetic protein-2 (BMP-2)-induced ectopic bone formation, we implanted type I collagen disks containing constant amounts of BMP-2 (5 μg) and varying amounts of FGF-2 onto the back muscles of adult male mice. We then performed histological analyses and histomorphometry, and measured bone mineral density and radiopaque area on the discs 1, 2, and 3 weeks after implantation. We also determined the expression profiles of several genes involved in bone formation and the BMP signaling pathway in the muscle that had been adjacent to the implanted disc and in muscle-derived primary culture cells that had similarly been treated with a constant concentration of BMP-2 and a varying concentration of FGF-2. In the presence of a constant amount of BMP-2, we confirmed that low doses of FGF-2 increased ectopic bone formation in vivo and high doses inhibited bone formation. Northern and/or Western blots of recovered muscle from the in vivo experiment and treated muscle-derived primary culture cells from the in vitro experiment revealed that low doses of FGF-2, but not high doses, increased the expression BMP receptor (BMPR)-1B, phosphorylated Smad1, Noggin, and Osteocalcin. Our results indicate that low-dose FGF-2 may facilitate BMP-2-induced ectopic bone formation by altering the expression of BMPRs on the surface of bone forming progenitor cells. They also indicate that the inhibitory effect of high-dose FGF-2 is not mediated via increased expression of the BMP inhibitor Noggin. [Copyright &y& Elsevier]

Because various biomechanical studies and clinical results have shown the effectiveness of an anatomical approach for anterior cruciate ligament (ACL) reconstruction, this approach has become gradually commonplace to improve postoperative performance. Standard tunnel positioning methods with accuracy, reproducibility, and adaptability to varied concepts are essential for the success of anatomical ACL reconstruction. However, there were no standard tibial tunnel positioning methods to satisfy these conditions. This technical note reports our tibial tunnel positioning technique using bony and/or anatomical landmarks for anatomical ACL reconstruction. [ABSTRACT FROM AUTHOR]