Accuracy of robotic arm-assisted versus computed tomography-based navigation in total hip arthroplasty using the direct anterior approach: a retrospective study.

BACKGROUND: A robotic arm-assisted and a computed tomography (CT)- based navigation system have been reported to improve the accuracy of component positioning in total hip arthroplasty (THA). However, no study has compared robotic arm-assisted THA (rTHA) to CT-based navigated THA (nTHA) concerning accuracy of cup placement and acetabular fractures using the direct anterior approach (DAA). This study aimed to compare the accuracy of cup placement and the presence of intraoperative acetabular fractures between rTHA and nTHA using DAA in the supine position. METHODS: We retrospectively investigated 209 hips of 188 patients who underwent rTHA or nTHA using DAA (rTHA using the Mako system: 85 hips of 79 patients; nTHA: 124 hips of 109 patients). After propensity score matching for age and sex, each group consisted of 73 hips. We evaluated clinical and radiographic outcomes, comparing postoperative cup orientation and position, measured using a three-dimensional templating software, to preoperative CT planning. Additionally, we investigated the prevalence of occult acetabular fracture. RESULTS: Clinical outcomes were not significantly different between the groups at 1 year postoperatively. The mean absolute error of cup orientation was significantly smaller in the rTHA group than in nTHA (inclination: 1.4° ± 1.2° vs. 2.7° ± 2.2°, respectively; p = 0.0001, anteversion: 1.5° ± 1.3° vs. 2.2° ± 1.7°, respectively; p = 0.007). The cases within an absolute error of 5 degrees in both RI and RA were significantly higher in the rTHA (97.3%) than in nTHA group (82.2%) (p = 0.003). The absolute error of the cup position was not significantly different between the two groups. The prevalence of occult acetabular fracture did not differ significantly between the two groups (rTHA: n = 0 [0%] vs. nTHA: n = 1 [1.4%]). CONCLUSION: Cup placement using DAA in the supine position in rTHA was more accurate with fewer outliers compared to nTHA. Therefore, rTHA performed via DAA in a supine position would be useful for accurate cup placement.

Comparison of simultaneous versus staged bilateral total hip arthroplasty via the direct anterior approach: A propensity score matched analysis.

PURPOSE: It remains unclear whether simultaneous bilateral total hip arthroplasty (SimBTHA) or staged bilateral total hip arthroplasty (StaBTHA) is clinically superior. No study has compared these two procedures matching surgical approach and patient background. This study aimed to clarify the differences between SimBTHA using direct anterior approach (SimBTHA-DAA) and StaBTHA using the direct anterior approach (StaBTHA-DAA). METHODS: Patients who underwent THA between 2012 and 2020 were enrolled, resulting in a total of 1658 hips of 1388 patients. After propensity score matching for patient background, 204 hips of 102 patients (51 patients in each group) were examined. Clinical and radiographic outcomes, complications, intraoperative blood loss and blood transfusions (BT) were evaluated. In complications, we evaluated periprosthetic fractures, pulmonary embolism, deep venous thrombosis, surgical site infection and dislocation. RESULTS: At the final follow-up, clinical and radiographic outcomes and complications were not significantly different between the groups. Intraoperative blood loss was equivalent for SimBTHA and the sum in the first- and second-stage StaBTHA. The total-BT rate was significantly higher for SimBTHA-DAA than for StaBTHA-DAA (p < .0001). The allogeneic BT rate was significantly higher in SimBTHA-DAA in the supine position (32.3%) than in StaBTHA-DAA (8.3%) (p = .007). However, no patient who received autologous BT required allogeneic BT. CONCLUSIONS: Clinical and radiographic outcomes were equivalent between SimBTHA-DAA and StaBTHA-DAA. The allogeneic BT rate was significantly higher in SimBTHA-DAA than in StaBTHA-DAA. Autologous BT reduced the use of allogeneic BT in SimBTHA-DAA. Auto-BT may be useful for avoiding allo-BT in SimBTHA.

Repair of patellar tendon rupture after total knee arthroplasty using knotless suture bridge technique: a case report.

Few studies have reported on the use of knotless suture anchors to treat patellar tendon rupture from tibial tuberosity after total knee arthroplasty (TKA). We report a case of patellar tendon rupture in an 82-year-old female. She fell 8 weeks after bilateral TKA and presented with a patellar tendon rupture. A knotless suture anchor and a fully threaded Twist-In knotless anchor with flat-braided suture were used to repairing the patellar tendon. Complications related to the extension mechanism after TKA can lead to disastrous consequences. This surgical procedure is a safe and good treatment option to repair patellar tendon rupture after TKA.

Can accuracy with the iASSIST navigation be confirmed by assessment? A multi-center prospective randomized controlled trial with independent three-dimensional image assessment.

BACKGROUND: iASSIST is one of the novel accelerometer-based navigation systems for total knee arthroplasty (TKA). Although the accuracy of iASSIST compared with conventional instruments has been reported, such evaluations were performed on two-dimensional (2D) images (X-rays). This multi-center prospective randomized controlled trial aimed to assess component positioning between TKA with and without iASSIST by 3D image assessment, and to clarify whether the iASSIST provides any benefit with regard to alignment accuracy. METHODS: Eighty-three knees with primary knee osteoarthritis were enrolled in this study. iASSIST was used for distal femoral and proximal tibial resection in 42 knees (iA group) and a conventional guide was used in 41 knees (CONV group). At 6 months postoperatively, component alignment was evaluated with 3D images by the independent orthopaedic surgeons, and surgical parameters, range of motion and clinical outcomes were examined. RESULTS: The rate of knees who have the alignment within 3° of neutral compared with the iA group and CONV group were 92.9% (39/42) vs. 87.8% (36/41) for femur and 76.2% (32/42) vs. 56.1% (23/41) for tibia in the coronal plane, respectively, whereas in the sagittal plane, the rate was 85.7% (36/42) vs. 58.5% (24/41) for femur and 83.3% (35/42) vs. 78.0% (32/41) for tibia, respectively. Compared with the CONV group, the iA group had a significantly improved femoral alignment in the sagittal plane (P = 0.006). There were no clinical or patient-reported differences at 6 months postoperatively. CONCLUSIONS: The iASSIST provides technically high accuracy in femoral resection at TKA compared with a conventional procedure.

Effects of basic fibroblast growth factor on the repair of large osteochondral defects of articular cartilage in rabbits: dose-response effects and long-term outcomes.

Articular cartilage possesses a limited capacity for self-renewal. The regenerated tissue often resembles fibrocartilage-like tissue rather than hyaline cartilage, and degeneration of the articular surface eventually occurs. The purpose of this study was to investigate the effect of basic fibroblast growth factor (bFGF) on the healing of full-thickness articular cartilage defects. bFGF (0, 10, 50, 100, 250, 500, or 1000 ng) was mixed with collagen gel and implanted into full-thickness articular cartilage defects drilled into rabbit knees. The repaired tissue was examined grossly and histologically, and was evaluated with the use of a grading scale at 4, 12, 24, and 50 weeks. At 4 weeks, treatment with 100 ng of bFGF had greatly stimulated cartilage repair both grossly and histologically in comparison with untreated defects (those filled with plain collagen gel). The average total scores on the histological grading scale were significantly better for the defects treated with bFGF than for the untreated defects. These improvements were evident as long as 50 weeks postoperatively, although slight deterioration was noted in the repaired cartilage. Immunohistochemical staining for type II collagen showed that this cartilage-specific collagen was diffusely distributed in the repaired tissue at 50 weeks. These findings suggest that bFGF may be a practical and important candidate for use in cartilage repair.

Dexamethasone induces human spinal ligament derived cells toward osteogenic differentiation.

Ossification of spinal ligament is characterized by heterotopic bone formation in the spinal ligaments that are normally composed of fibrous tissues. The pathogenesis of ossification of spinal ligament has been suggested to be associated with osteogenic differentiation of the spinal ligament cells. In order to address this hypothesis, cells derived from human spinal ligament were investigated for their osteogenic potential by the treatment of dexamethasone in vitro. Yellow ligaments were obtained from patients with spinal disorders except ossification of spinal ligament during surgery, and the adhering tissues were removed completely. Most of the ligament cells treated with vehicle exhibited a fibroblast-like spindle shape, while the dexamethasone-treated cells acquired a polygonal morphology. Growth of the ligament cells was suppressed by dexamethasone at a high concentration. Some of the vehicle treated-cells were alkaline phosphatase-positive, and dexamethasone increased the alkaline phosphatase-positive cells and alkaline phosphatase activity in the cells. Northern blot analysis demonstrated that mRNAs expression of pro-alpha1(I) collagen and alkaline phosphatase were promoted by dexamethasone. Analysis by reverse transcription-polymerase chain reaction showed that expression of osteocalcin mRNA was detected in the dexamethasone-treated cells but not in the vehicle-treated cells, and dexamethasone-induced osteocalcin mRNA expression was promoted by 1,25-dihydroxyvitamin D(3). Finally, mineralization of extracellular matrix in the cells was induced by the presence of dexamethasone and 1,25-dihydroxyvitamin D(3). These results suggest for the first time that dexamethasone has a possible involvement in the osteoblastic differentiation of human spinal ligament cells.