Comparison of short-term clinical results between modified kinematically-aligned and guided motion bicruciate stabilized total knee arthroplasty.

BACKGROUND: Both kinematically-aligned (KA) total knee arthroplasty (TKA) and bicruciate stabilized (BCS) TKA aim to reproduce the physiological knee kinematics. In this study, we compared the femoro-tibial component rotational mismatch between patients who underwent modified KA-TKA and those who received guided-motion BCS-TKA, and its influence on the clinical outcomes. METHODS: In this retrospective study, 77 consecutive patients were included and divided into two groups: subjects who underwent modified KA-TKA with Persona (KA Group; n = 42) and those who received BCS-TKA with JOURNEY II (BCS group; n = 35). Range of motion, the 2011 Knee Society Score (KSS), the rotational alignment of the femoral and tibial components, and the correlations between the rotational mismatch and the 2011 KSS subscales were examined. RESULTS: The postoperative objective knee indicators (P = 0.0157), patient satisfaction (P = 0.0039) and functional activity scores (P = 0.0013) in the KA group were significantly superior to those in the BCS group 1 year postoperatively. There was no significant difference between the two groups observed in the rotational mismatch. In the BCS group, significant negative correlations were identified between the rotational mismatch and objective indicators, patient satisfaction, and functional activity scores but not in the KA group. CONCLUSIONS: The short-term clinical results following KA-TKA showed superior objective knee indicators, patient satisfaction and functional activity scores. A negative correlation was observed between component rotational mismatch and the 2011 KSS subscales in the BCS group, compared to no relationship found between the two in the KA group. These findings suggested that KA-TKA has a relatively higher tolerance for rotational mismatch than BCS-TKA.

Combined assessment of acetabular coverage and femoral head-neck shapes predicts osteoarthritis progression after periacetabular osteotomy.

INTRODUCTION: Postoperative osteoarthritis (OA) progression is a major determinant of failure after curved periacetabular osteotomy (CPO). A large postoperative combination angle, i.e., the combination of computed tomography-based anterior center edge and alpha angles, is associated with femoroacetabular impingement after CPO, but its association with postoperative OA progression is unclear. We aimed to identify the anatomical parameters that can lead to OA progression after CPO and the impact of the combination angle on the same. MATERIALS AND METHODS: We included 90 hips that were subjected to CPO at our center between March 2013 and March 2018. Seventeen hips showed OA progression with an increase in the Tönnis classification after surgery; 73 hips showed no progression. Radiographic anatomical parameters, including the lateral and anterior center edge angles, femoral and acetabular anteversion, and combination angle, and clinical outcomes, including modified Harris Hip Scores (mHHSs), postoperative anterior impingement, and range of motion, were compared between the two groups. Statistical significance was set at P < 0.05. RESULTS: Postoperative OA progression was significantly affected by preoperative OA evidence (P = 0.017), acetabular anteversion < 5.0° (P = 0.003), and a combination angle > 107.0° (P = 0.025). Patients with radiographic OA progression were associated with poor mHHSs (P = 0.017) and high frequencies of anterior impingement with a limited hip flexion and internal rotation angle. CONCLUSIONS: OA progression after CPO may be associated with preoperative evidence of OA and postoperative acetabular retroversion as well as a large combination angle. Surgeons should focus on the potential effects of preoperative OA grades, postoperative reduction in acetabular anteversion, and postoperative combination angle.

The Utility and Feasibility of Smart Glasses in Spine Surgery: Minimizing Radiation Exposure During Percutaneous Pedicle Screw Insertion.

OBJECTIVE: Spine surgeons are often at risk of radiation exposure due to intraoperative fluoroscopy, leading to health concerns such as carcinogenesis. This is due to the increasing use of percutaneous pedicle screw (PPS) in spinal surgeries, resulting from the widespread adoption of minimally invasive spine stabilization. This study aimed to elucidate the effectiveness of smart glasses (SG) in PPS insertion under fluoroscopy. METHODS: SG were used as an alternative screen for fluoroscopic images. Operators A (2-year experience in spine surgery) and B (9-year experience) inserted the PPS into the bilateral L1-5 pedicles of the lumbar model bone under fluoroscopic guidance, repeating this procedure twice with and without SG (groups SG and N-SG, respectively). Each vertebral body's insertion time, radiation dose, and radiation exposure time were measured, and the deviation in screw trajectories was evaluated. RESULTS: The groups SG and N-SG showed no significant difference in insertion time for the overall procedure and each operator. However, group SG had a significantly shorter radiation exposure time than group N-SG for the overall procedure (109.1 ± 43.5 seconds vs. 150.9 ± 38.7 seconds; p = 0.003) and operator A (100.0 ± 29.0 seconds vs. 157.9 ± 42.8 seconds; p = 0.003). The radiation dose was also significantly lower in group SG than in group N-SG for the overall procedure (1.3 ± 0.6 mGy vs. 1.7 ± 0.5 mGy; p = 0.023) and operator A (1.2 ± 0.4 mGy vs. 1.8 ± 0.5 mGy; p = 0.013). The 2 groups showed no significant difference in screw deviation. CONCLUSION: The application of SG in fluoroscopic imaging for PPS insertion holds potential as a useful method for reducing radiation exposure.

Intraoperative lateral laxity greater than 4° is associated with inferior functional improvement in posterior-stabilised total knee arthroplasty.

PURPOSE: The study aimed to determine the impact of intraoperative lateral laxity at extension on clinical and functional outcomes 1 year after posterior-stabilised total knee arthroplasty (PS-TKA). METHODS: In total, 91 varus-type osteoarthritic knees that underwent PS-TKA using the medial preservation gap technique were included. After the femoral trial component placement and patellofemoral joint reduction, the soft-tissue balance was assessed using an offset-type tensor with a 40-lb joint-distraction force. Patients were divided into the following three groups according to the intraoperative lateral laxity at extension (i.e., varus ligament balance) using the mean ± 1 standard deviation: Groups A, ≤0°; B, 0-4°; and C, >4°. The 2011 Knee Society Score (KSS) and 3-m timed up-and-go test (TUG) time 1-year postoperatively, and their improvements were compared among the groups. RESULTS: While significant improvements were observed in all subscales of the 2011 KSS and TUG post-TKA (p < 0.05), the improvement of functional activities and TUG time were significantly lower in Group C than in Group B (p < 0.05). However, no significant differences were observed in symptom improvement, patient satisfaction or patient expectation scores among the groups. CONCLUSION: An excessive lateral laxity (varus angle) >4° at extension was associated with lower improvement in functional ability 1-year postoperatively. Therefore, excessive intraoperative lateral laxity should be avoided in PS-TKA. LEVEL OF EVIDENCE: Level IV.

Rotating Hinge Knee Arthroplasty for Charcot Joints of the Knees in Patients With Charcot-Marie-Tooth Disease: A Report of Two Cases.

We report two cases wherein rotating hinge knee (RHK) arthroplasty was performed for Charcot joints that developed secondary to Charcot-Marie-Tooth disease (CMT).  Case 1 was of a 74-year-old woman with CMT. She presented with muscle weakness and sensory disturbances of the distal lower limbs, deformity, and significant medial instability of the bilateral knees. She was then diagnosed with Charcot joints of the knees secondary to CMT, which were treated with RHK arthroplasty. Five years postoperatively, there was no instability, and she was able to stand unassisted without pain. Case 2 was a 90-year-old woman with CMT who presented with muscle weakness and sensory disturbances of the distal lower limbs, deformity, and significant medial instability of the bilateral knees. She was then diagnosed with Charcot joints of the knees secondary to CMT, which were also treated with RHK arthroplasty. One year postoperatively, there was no instability, and she was able to walk smoothly using a walker. These clinical cases indicate that RHK arthroplasty can be a good therapeutic option for Charcot joints of the knees in patients with CMT.

Goal Orientation and Desire for Approval Were Associated With Sports Injuries Among Young Japanese Athletes.

Introduction: This study aimed to clarify the relationship between psychological factors (goal orientation and desire for approval from others) and the severity of sports injuries experienced by young Japanese athletes. Methods: A total of 560 young Japanese athletes (328 males and 232 females) aged 18-24 years completed an online survey in 2022-2023. A web questionnaire was used to investigate participants' task and ego orientations, desire for approval from others (e.g., coaches and friends/families), and history of injury. The samples were then split into 3 groups on the basis of the rest duration due to the injury: noninjury group (0 days), mild-to-moderate injury group (1-27 days), and severe injury group (>28 days). Spearman's test examined a correlation between task and ego orientation scores among all samples. The Mann-Whitney U test was used to compare the scores between the severe injury and noninjury groups. Result: A significant positive correlation was found between task and ego orientation scores from all samples (ρ=0.27, p<0.001). The severe injury group had significantly higher task orientation scores and desire for approval scores than the noninjury group (ρ=0.001, p<0.001). Conclusions: Japanese young athletes with high task orientation and approval desire may be at risk of severe sports injuries requiring >4 weeks to return to sports. The goal orientation profiles should be interpreted with caution. Future research should examine contextual effects such as the perceived motivational climate, in addition to the goal orientation profiles.

Variations in knee cartilage thickness: Fully automatic three-dimensional analysis of MRIs from five manufacturers.

BACKGROUND: Measurements of knee cartilage thickness derived from MR images are attractive biomarkers for osteoarthritis research. Although some cross-sectional multivendor studies exist, none have employed fully automatic three-dimensional MRI analysis. Our objective was to evaluate the variations in knee cartilage thickness measurements obtained using automated methods and MRI instruments from five different vendors. METHODS: The subjects were 10 healthy volunteers aged 22-60 years. MRI models with 3 Tesla strength from five different companies were used. Cartilage thickness was quantified fully automatically for seven regions. We hypothesized that "the MRI model influences cartilage thickness measurements." Inter-measurement error, defined as the absolute difference between the targeted and median thicknesses determined by the five MRI models, was analyzed using histograms. The factors generating the largest inter-measurement error were also examined. RESULTS: No exceptional trends attributable to a specific instrument model were observed, and the p-value from the Kruskal-Wallis test exceeded 0.05 in all seven regions. Therefore, the study hypothesis was rejected. Of the 350 measurements, the inter-measurement error was ≤0.05 mm in 53 %, ≤0.10 mm in 75 %, and ≤0.20 mm in 95 %. Analysis of the medial tibial cartilage, which had the largest inter-measurement error, revealed mis-extraction of synovial fluid as cartilage. CONCLUSIONS: The choice of MRI model did not influence cartilage thickness measurements. Overall, 95 % of the inter-measurement errors were within 0.20 mm. The greatest error resulted from mis-extracting synovial fluid as cartilage.

The assessment of canal flare index and proximal femoral bone density can improve stem selection for peri-prosthetic bone maintenance after total hip arthroplasty.

INTRODUCTION: Bone maintenance after total hip arthroplasty (THA) is important for implant success. This study aimed to investigate the relationship between patient characteristics and periprosthetic bone maintenance after THA for better implant selection. MATERIALS AND METHODS: This retrospective cohort study enrolled 112 consecutive patients who underwent THA using full hydroxyapatite (HA) compaction with short (n = 55) or short-tapered wedge (n = 61) stems. Periprosthetic bone mineral density (BMD) was compared between the two groups after propensity score matching, and the relationship between periprosthetic BMD changes and patient background was analyzed. RESULTS: Both groups showed similar periprosthetic BMD changes after adjusting for patient background using propensity score matching. Canal flare index > 3.7 in patients that underwent THA using tapered-wedge stem (odds ratio (OR), 3.2; 95% confidence interval (CI), 1.3-7.9, p = 0.013) and baseline zone 1 BMD > 0.65 in patients that received with short HA compaction stems (OR, 430.0; 95% CI 1.3-1420, p = 0.040) were associated with proximal periprosthetic bone maintenance after THA. CONCLUSION: Considering their predictive value, canal flare index and zone 1 BMD assessment might be useful strategies for implant selection during THA.

Estimating the Thumb Rotation Angle by Using a Tablet Device With a Posture Estimation Artificial Intelligence Model.

MediaPipe Hand (MediaPipe) is an artificial intelligence (AI)-based pose estimation library. In this study, MediaPipe was combined with four machine learning (ML) models to estimate the rotation angle of the thumb. Videos of the right hands of 15 healthy volunteers were recorded and processed into 9000 images. The rotation angle of the thumb (defined as angle θ from the palmar plane, which is defined as 0°) was measured using an angle measuring device, expressed in a radian system. Angle θ was then estimated by the ML model by using parameters calculated from the hand coordinates detected by MediaPipe. The linear regression model showed a root mean square error (RMSE) of 12.23, a mean absolute error (MAE) of 9.9, and a correlation coefficient of 0.91. The ElasticNet model showed an RMSE of 12.23, an MAE of 9.95, and a correlation coefficient of 0.91; the support vector machine (SVM) model showed an RMSE of 4.7, an MAE of 2.5, and a correlation coefficient of 0.99. The LightGBM model achieved high values: an RMSE of 4.58, an MAE of 2.62, and a correlation coefficient of 0.99. Based on these findings, we concluded that the thumb rotation angle can be estimated with high accuracy by combining MediaPipe and ML.

Estimation of Shoulder Joint Rotation Angle Using Tablet Device and Pose Estimation Artificial Intelligence Model.

Traditionally, angle measurements have been performed using a goniometer, but the complex motion of shoulder movement has made these measurements intricate. The angle of rotation of the shoulder is particularly difficult to measure from an upright position because of the complicated base and moving axes. In this study, we attempted to estimate the shoulder joint internal/external rotation angle using the combination of pose estimation artificial intelligence (AI) and a machine learning model. Videos of the right shoulder of 10 healthy volunteers (10 males, mean age 37.7 years, mean height 168.3 cm, mean weight 72.7 kg, mean BMI 25.6) were recorded and processed into 10,608 images. Parameters were created using the coordinates measured from the posture estimation AI, and these were used to train the machine learning model. The measured values from the smartphone's angle device were used as the true values to create a machine learning model. When measuring the parameters at each angle, we compared the performance of the machine learning model using both linear regression and Light GBM. When the pose estimation AI was trained using linear regression, a correlation coefficient of 0.971 was achieved, with a mean absolute error (MAE) of 5.778. When trained with Light GBM, the correlation coefficient was 0.999 and the MAE was 0.945. This method enables the estimation of internal and external rotation angles from a direct-facing position. This approach is considered to be valuable for analyzing motor movements during sports and rehabilitation.

Morphological analysis of the distal femur as a surgical reference in biplane distal femoral osteotomy.

Distal femoral osteotomy (DFO) is performed alone or with high tibial osteotomy (HTO) for patients with osteoarthritis and distal femur deformities. DFO is technically demanding, particularly when creating an anterior flange. Herein, we examined the morphological characteristics of the distal femur based on the cortical shape as a surgical reference for biplanar DFO. Computed tomography images of 50 valgus and 50 varus knees of patients who underwent biplanar DFO or total knee arthroplasty were analyzed. Axial slices at the initial level of the transverse osteotomy in the DFO and slices 10 mm proximal and 10 mm distal to that level were selected. The medial and lateral cortical angles and heights (MCLA, LCLA, MCH, and LCH) were measured on axial slices. Statistical comparisons were performed between the medial and lateral cortices and valgus and varus knees. MCLA and MCH were significantly smaller and lower, respectively, than LCLA and LCH (P < 0.01). The MCLA and MCH of varus knees were significantly smaller and lower, respectively, than those of valgus knees (P < 0.01). Surgeons should carefully observe morphological differences in the distal femur cortex, distinguishing between medial and lateral knees and varus and valgus knees during the creation of the anterior flange in the DFO.

Accuracy of portable navigation during THA in patients with severe developmental dysplasia of hip.

INTRODUCTION: Correct cup placement in total hip arthroplasty (THA) for patients with developmental dysplasia of the hip (DDH) is considerably difficult. This study aimed to analyze the orientation accuracy of cup insertion during THA using a portable navigation system in patients with DDH. MATERIALS AND METHODS: In this retrospective cohort study, we analyzed data from 64 patients who underwent THA using infrared stereo camera-matching portable navigation. Patients underwent THA via the anterolateral approach in the lateral decubitus position. Navigation records for intraoperative cup angles, postoperative cup angles measured on computed tomography (CT) images, and cup angle measurement differences were measured and compared between patients with non-DDH/mild DDH and severe DDH. Furthermore, the predictive factors for outliers of accurate acetabular cup placement were analyzed. RESULTS: The average measurement absolute abduction differences (postoperative CT-navigation record) were 3.9 ± 3.5° (severe DDH) and 3.3 ± 2.6° (non-DDH/ mild DDH), and the anteversion differences were 4.7 ± 3.4° (severe DDH) and 2.3 ± 2.1° (non-DDH/ mild DDH). The anteversion difference was different between the two groups. Multivariate analysis showed that the navigation difference (absolute difference in anteversion between postoperative CT and navigation records of > 5°) was significantly associated with severe DDH (odds ratio [OR]: 3.3; p = 0.049, 95% confidence interval [CI]: 1.0-11.1) and posterior pelvic tilt (OR: 1.1; p = 0.042, 95% CI: 1.0-1.27). CONCLUSIONS: In patients with severe DDH, it is important to pay close attention during THA using portable navigation. However, the average difference was < 5º even in patients with severe DDH, and the accuracy may be acceptable in a clinical setting when the cost is considered.

What effect does preoperative flexion contracture have on the component angles in unicompartmental knee arthroplasty?

PURPOSE: The indication for unicompartmental knee arthroplasty (UKA) has been extended to cases with some degree of preoperative knee flexion contracture recently. The purpose of this study was to clarify the effect of flexion contracture on component angles. MATERIALS AND METHODS: Thirty-five fixed-bearing UKAs using the spacer block technique with preoperative flexion contracture (Group FC) and 35 UKAs using the same technique without preoperative flexion contracture (Group NC) were included. Using radiographs, the coronal femoral component angle, coronal tibial component angle, sagittal femoral component angle, and sagittal tibial component angle were determined. Also, extension and flexion angles of the knee as well as coronal Hip-Knee-Ankle (HKA) angles in long-leg standing radiographs were measured. The data about the thickness of the selected insert were also collected. The above results were compared between the two groups. RESULTS: The femoral component tended to be placed in a more varus and flexed position in Group FC, while no significant difference was found about the tibial component angles. While there was no significant difference in pre- and postoperative knee flexion angles between the two groups, flexion contracture remained postoperatively in Group FC. Preoperative HKA angle was greater in Group FC while the difference was no longer significant postoperatively. Regarding the thickness of the selected insert, thicker inserts tended to be used in Group FC. CONCLUSIONS: In fixed-bearing UKA with the spacer block technique, the femoral component tended to be placed in a flexed and varus position in the knees with preoperative flexion contracture.

Injuries to both anterolateral ligament and Kaplan fiber of the iliotibial band do not increase preoperative pivot-shift phenomenon in ACL injury.

Background: To assess the incidence of anterolateral ligament (ALL) and Kaplan fiber of the iliotibial band (KF) injuries in patients with acute anterior cruciate ligament (ACL) injury on magnetic resonance imaging (MRI), and to investigate the association between these injuries and the magnitude of preoperative pivot-shift test. Method: One-hundred and five patients with primary ACL injury were retrospectively reviewed. ALL injury and KF injury were assessed by preoperative MRI, and subjects were allocated into four groups: Group A, neither injury; Group B, only ALL injury; Group C, only KF injury; Group D, simultaneous ALL and KF injuries. Before ACL reconstruction, tibial acceleration during the pivot-shift test was measured by an electromagnetic measurement system, and manual grading was recorded according to the International Knee Documentation Committee (IKDC) guideline. Results: In MRI, the ALL was identified in 104 patients (99.1%) and KF in 99 patients (94.3%). ALL and KF injuries were observed in 43 patients (43.9%) and 23 patients (23.5%), respectively. Patient distribution to each group was as follows; Group A: 43 patients (43.9%), Group B: 32 patients (32.7%), Group C: 12 patients (12.2%), Group D: 11 patients (11.2%). No significant differences were observed in tibial acceleration, and manual grading among the four groups. Conclusion: Simultaneous injury to both ALL and KF was uncommon, and preoperative pivot-shift phenomenon did not increase even in those patients. The finding suggests that the role of ALL and KF in controlling anterolateral rotatory knee laxity may be less evident in the clinical setting compared to a biomechanical test setting.

Association Between Psychological Readiness to Return to Sports at 3 Months Postoperatively and Risk of Second ACL Injury.

Background: Psychological readiness to return to sports (RTS) has been associated with second anterior cruciate ligament (ACL) injury. However, this relationship is controversial because covariates such as anatomic and knee function characteristics have not been adequately considered. Purpose/Hypothesis: To investigate whether psychological readiness in the early postoperative period can predict the occurrence of a second ACL injury within 24 months after primary ACL reconstruction (ACLR) using propensity score analysis. It was hypothesized that patients with high ACL-RSI after injury (ACL-RSI) scores at 3 months postoperatively would have a second ACL injury within the projected postoperative period. Study Design: Cohort study; Level of evidence, 3. Methods: Included were 169 patients who underwent primary ACLR using hamstring tendon autografts between November 2017 and July 2021 and also underwent knee functional assessments at 3 months postoperatively. The ACL-RSI scale was used to assess psychological readiness for RTS. A second ACL injury was defined if ipsilateral or contralateral ACL injury was confirmed by examination within 24 months postoperatively. Based on a previous study showing that 65 was the highest cutoff value for the ACL-RSI score for RTS, we classified patients into 2 groups: those with high ACL-RSI scores (≥65; group H) and those with low ACL-RSI scores (<65; group L). We generated 1-to-1 matched pairs using propensity score analysis and used log-rank testing to compare the rate of second ACL injury between the 2 groups. Results: More patients returned to any sports activities within 12 months in group H than in group L (90% vs 73%; P = .03). A second ACL injury within 24 months postoperatively was identified in 7% of patients (13/169). The rate of second ACL injury was significantly higher in group H than in group L (17.6% vs 3.4%; P = .001). In 43 matched pairs extracted using propensity scoring, the rate of second ACL injury was also higher in group H than in group L (18.6% vs 4.7%; P = .04). Conclusion: Patients with a higher ACL-RSI score at 3 months exhibited a significantly higher incidence of second ACL injury within 24 months after primary ACLR.

Setting hinge position distal to the proximal margin of the distal lateral femur reduces the maximum principal strains of the hinge area and risk of hinge fractures.

Purpose: The optimal hinge position to prevent hinge fractures in medial closing wedge distal femoral osteotomy (MCWDFO) based on the biomechanical background has not yet been well examined. This study aimed to examine the appropriate hinge position in MCWDFO using finite element (FE) analysis to prevent hinge fractures. Methods: Computer-aided design (CAD) models were created using composite replicate femurs. FE models of the MCWDFO with a 5° wedge were created with three different hinge positions: (A) 5 mm proximal to the proximal margin of the lateral epicondylar region, (B) proximal margin level and (C) 5 mm distal to the proximal margin level. The maximum and minimum principal strains in the cortical bone were calculated for each model. To validate the FE analysis, biomechanical tests were performed using composite replicate femurs with the same hinge position models as those in the FE analysis. Results: In the FE analysis, the maximum principal strains were in the order of Models A > B > C. The highest value of maximum principal strain was observed in the area proximal to the hinge. In the biomechanical test, hinge fractures occurred in the area proximal to the hinge in Models A and B, whereas the gap closed completely without hinge fractures in Model C. Fractures occurred in an area similar to where the highest maximal principal strain was observed in the FE analysis. Conclusion: Distal to the proximal margin of the lateral epicondylar region is an appropriate hinge position in MCWDFO to prevent hinge fractures. Level of Evidence: Level V.

Treatment of Osteoporosis in Men on Androgen Deprivation Therapy in Japan.

Background and Objectives: Androgen deprivation therapy (ADT) for prostate cancer has greatly improved treatment outcomes. As patient survival rates have increased, reports of decreased bone density and increased bone fractures as side effects of ADT have emerged. The prevalence of osteoporosis in Japanese men was 4.6%. The purpose of this study was to evaluate the effect of osteoporosis treatment in prostate cancer patients who underwent ADT in Japan. Materials and Methods: The subjects were 33 male patients who had undergone ADT for prostate cancer, who were noted to have decreased bone density. Mean age was 76.2 ± 7.7 years (64-87). Medications included vitamin D in one case, bisphosphonates (BP) in 27 cases, and denosumab in five cases. The evaluation method examined the rate of change in bone mineral density (BMD) before osteoporosis treatment and 1 year after. For comparison, a group without osteoporosis treatment intervention (n = 33) was selected, and matched for prostate cancer treatment and age. The rate of change in trabecular bone score (TBS) was also calculated. Results: The percentage changes in BMD before and 1 year after treatment were as follows: lumbar spine, 7.1 ± 5.8% in the treatment group versus -3.9 ± 4.1% in the no treatment group; femoral neck, 5.5 ± 6.2% in the treatment group versus -0.9 ± 3.9% in the no treatment group; total femur, 6.6 ± 6.4% in the treatment group versus the no treatment group which was -1.7 ± 3.2%. In all cases, there was a clear significant difference (p < 0.01). The percent change in TBS was further calculated in the same manner. There was no significant difference between the two groups: +1.7 ± 3.8% in the treated group versus +0.3 ± 4.1% in the untreated group. Conclusions: Osteoporosis treatment in Japanese patients with prostate cancer on ADT therapy was found to significantly increase BMD compared to the untreated group. BP and denosumab were found to be very effective in increasing BMD.

Prediction of Postoperative Range of Motion after Mobile-Bearing Medial Unicompartmental Knee Arthroplasty from the Preoperative Range of Motion and Other Preoperative Factors.

Postoperative flexion after unicompartmental knee arthroplasty might be predicted from the preoperative range of motion and other preoperative factors, but this has not been sufficiently investigated. Between 2013 and 2017, 198 patients (198 knees) underwent unilateral knee arthroplasty with medial mobile-bearing unicompartmental knee arthroplasty. Range of motion was measured preoperatively and at the time of final follow-up. To investigate the accuracy of the prediction of preoperative to postoperative gain or loss of the flexion angle, we performed receiver operating characteristic analysis. Logistic regression analysis was used to evaluate other predictive factors. Change in flexion angle was significantly strongly and negatively correlated with the preoperative flexion angle (R = - 0.688; 95% confidence interval: -0.755 to -0.607; p < 0.001). Preoperative flexion angle was suggested to be a significant predictor of gain or loss of the flexion angle with the area under the curve of 0.781; the cutoff value calculated using the Youden index was 140 degrees. Logistic regression analysis showed that in addition to the preoperative flexion angle of the operated side, the postoperative flexion range was significantly affected by the patient's height and by the preoperative flexion angle of the contralateral knee. If the preoperative flexion angle in Oxford mobile-bearing medial unicompartmental knee arthroplasty is <140 degrees, the postoperative flexion angle may be improved; if it exceeds 140 degrees, the postoperative flexion angle may worsen. This predictive ability is further improved by consideration of the patient's height and the range of motion on the contralateral side.

Lateral Collateral Ligament Reconstruction Using the Triceps Brachii Fascia for Posterolateral Rotatory Instability in Cubitus Varus: A Report of Two Cases.

A combination of osteotomy and ligament reconstruction is recommended for posterolateral rotatory instability (PLRI) with large cubitus varus deformities. There is a lack of reports regarding ligament donor selection for ligament reconstruction of PLRI with cubitus varus. Two cases of PLRI with cubitus varus have been described. In case one, a 40-year-old woman presented with left elbow pain. She had a cubitus varus deformity, resulting from a childhood elbow fracture. Radiographs showed an 18-degree cubitus varus deformity. A lateral closing wedge osteotomy and double plate osteosynthesis were performed. The lateral collateral ligament (LCL) was reconstructed with autologous triceps fascia. Postoperative radiographs confirmed correction with 10 degrees of the carrying angle (CA). Bone union at the osteotomy site occurred six months later with excellent results. In case two, a 45-year-old man presented an arm with persistent right elbow instability with cubitus varus deformity. This was due to a childhood supracondylar fracture of the right humerus. Radiographs showed a cubitus varus deformity of 25 degrees on the right. The surgical procedure included a lateral wedge osteotomy, double plate fixation, and LCL reconstruction with autologous triceps fascia. Postoperative radiographs confirmed a corrected CA of 5 degrees. Bone union was achieved at the six-month follow-up with satisfactory results. The use of triceps fascia for LCL reconstruction for PLRI due to cubitus varus would provide a minimally invasive and reasonable treatment option.

Mid- to Long-Term Results of Total Knee Arthroplasty for Charcot Arthropathy of the Knee.

Background: Total knee arthroplasty (TKA) for Charcot arthropathy of the knee is considered controversial because of its higher complication rate compared with that of TKA for osteoarthritis. In this study, we investigated the clinical outcomes, survival rates, and complications of primary TKA for Charcot arthropathy. Methods: We conducted a retrospective analysis of nine patients (12 knees) with Charcot arthropathy who underwent TKA. The mean age of the patients was 63.9 ± 9.4 years (range, 52-83 years). The most frequent causative disease was diabetes mellitus (three patients). Patients' clinical outcomes, including the 2011 Knee Society Score and the range of motion, were compared between preoperative and the most recent postoperative data. The 5- and 10-year survival rates for aseptic revision, revision due to infection, and complications were examined. The mean follow-up period was 7.3 ± 3.9 years (range, 3-14 years). Results: The 2011 Knee Society Score and the knee flexion angle significantly improved after TKA surgery (P < 0.05). The 5-year survival rates for aseptic revision, revision due to infection, and complications were 100%, 91.7%, and 83.3%, respectively; the 10-year survival rates for these parameters were the same. One patient underwent revision for insert replacement due to periprosthetic infection, and the other patient had varus/valgus instability due to soft tissue loosening. Conclusions: The mid- to long-term results of TKA for Charcot arthropathy were generally favorable. Our findings indicate that TKA may be a viable treatment option for Charcot arthropathy.