Which fixation produces the best outcome for distal femoral fractures? Meta-analysis and systematic review of retrograde nailing versus distal femoral plating in 2432 patients and 33 studies.

PURPOSE: The distal femur comprises a wide intramedullary cavity and thin cortical bone. Firm internal fixation of comminuted fractures with displacement is challenging. Although many comparative studies have reported retrograde intramedullary nailing (RIN) and distal femoral plating (DFP) as the usual fixation methods for distal femoral fractures, no clear conclusion has been reached. Therefore, a meta-analysis and systematic review of the clinical and radiological results were conducted to determine the appropriate treatment method for distal femoral fractures. METHODS: A systematic search of the PubMed, Embase, Scopus, and Cochrane Library databases from their inception to December 19, 2022, was performed using predefined criteria. Studies comparing the effects of RIN and DFP were considered. The analyzed outcome measures included duration of surgery, blood loss, time to union, delayed union, nonunion, malalignment, implant failure, infection, reoperation, limb length discrepancy, range of motion, persistent anterior knee pain, knee stiffness, and functional scores. Meta-analysis of pooled data was conducted using a random-effects model to determine the standard mean difference (SMD) or odds ratio (OR) with 95% confidence intervals (CIs). RESULTS: Thirty-three studies with 2,432 patients were included. Compared to DFP, RIN was associated with a shorter time to fracture union (SMD, 1.83 months; 95% CI - 2.76 to - 0.90; P < 0.001) and a lower incidence of postoperative infection (OR 0.54; 95% CI 0.31-0.94; P = 0.03). Pooled analysis revealed no significant differences in other outcome measures between the two treatment modalities. CONCLUSION: In distal femoral fractures, RIN had a shorter bone union time and was more resistant to infection than DFP. However, there were no significant differences in the other clinical parameters. Therefore, the characteristics, strengths, and weaknesses of RIN and DFP should be carefully identified, and appropriate treatment should be provided based on the patient's medical condition and fracture pattern.

Stress Effect in the Knee Joint Based on the Fibular Osteotomy Level and Varus Deformity: A Finite Element Analysis Study.

Proximal fibular osteotomy (PFO) was found to relieve pain and improve knee function in patients with medial compartment knee osteoarthritis (OA). Therapy redistributes the load applied from the inside to the outside and alleviates the load applied on the inside through fibula osteotomy. Therefore, the clinical effect of fibular osteotomy using the finite element (FE) method was evaluated to calculate the exact change in stress inside a knee joint with varus deformity. Using CT and MRI images of a patient's lower extremities, 3D models of the bone, cartilage, meniscus, and ligaments were constructed. The varus angle, representing the inward angulation of the knee, was increased by applying a force ratio in the medial and lateral directions. The results showed that performing proximal fibular osteotomy led to a significant reduction in stress in the medial direction of the meniscus and cartilage. The stress reduction in the lateral direction was relatively minor. In conclusion, the study demonstrated that proximal fibular osteotomy effectively relieves stress and redistributes the load in the knee joints of patients with medial compartment knee osteoarthritis. The findings emphasize the importance of considering force distribution and the position of fibular osteotomy to achieve optimal clinical outcomes.

New Classification for Periprosthetic Distal Femoral Fractures Based on Locked-Plate Fixation Following Total Knee Arthroplasty: A Multicenter Study.

BACKGROUND: This study aimed to establish a new classification using locked-plate fixation for periprosthetic distal femoral fracture (PDFF) following total knee arthroplasty (TKA) and to determine when dual locked-plate fixation is necessary through defining this classification. METHODS: One-hundred fifteen consecutive PDFFs that underwent operative treatment were reviewed from 2011 to 2019 with minimum 1-year follow-up. Most PDFFs were fixed with single or dual locked-plate fixations using the minimally invasive plate osteosynthesis technique. Based on preoperative radiographs, PDFFs were classified according to the level of main fracture line relative to the anterior flange of femoral component: type I and II, main fracture line located proximal and distal to the anterior flange; and type III, component instability regardless of fracture line requiring revisional TKA. Furthermore, type II fractures were subclassified based on the direction of fracture beak as follows: type IIL, lateral-beak; type IIM, medial-beak. The incidence, treatment methods, and complications were analyzed according to the classification. RESULTS: Incidences of type I, IIL, IIM, and III were 64.4%, 8.7%, 24.3%, and 2.6%, respectively. Meanwhile, most PDFFs in type I and II were treated with lateral single locked-plate fixations, except for type IIM, which was treated with either single or dual locked-plate fixations. Overall complications were significantly higher in type II (28.9%) than in type I (10.8%, P = .019). In type IIM, bone union-related complications were significantly higher in single locked-plate fixation (50.0%) than in dual locked-plate fixation (5.6%; P = .013). CONCLUSION: The new classification provides practical and obvious strategies for the treatment of PDFF following TKA using locked-plate fixation. For type IIM fracture, dual plate fixation is necessary to prevent fixation failure or nonunion.

Alignment changes after open-wedge high tibial osteotomy result in offloading in the patellofemoral joint: a SPECT/CT analysis.

PURPOSE: The patellofemoral (PF) joint may be adversely affected by medial open-wedge high tibial osteotomy (OWHTO). This study aimed to evaluate the PF compartmental changes using combined single-photon emission computed tomography (SPECT) and conventional computed tomography (CT) after OWHTO to provide clinical guidance regarding the PF joint pressure and force. METHODS: Patients with medial osteoarthritis and varus malalignment > 5° were treated using OWHTO. Patients with a minimum 2-year follow-up were included in the study. The patellar positions were evaluated based on the radiographic parameters. The changes in chondral lesions during second-look arthroscopic examination were evaluated, and the PF joint arthritis grade was recorded on patellar Merchant radiographs using Kellgren-Lawrence classification. The PF compartmental changes according to SPECT/CT analysis after OWHTO were evaluated in all patients. The scintigraphic uptake was graded on four scales. Patients were divided into improved and unimproved groups according to the PF compartmental grade using the SPECT/CT uptake grading system. RESULTS: At a mean follow-up period of 47.0 months (range 25-74 months), the mean mechanical femorotibial angle changed significantly from varus 6.3° (range 5-12°) to valgus 2.6° (range 0-8°); p < 0.001) postoperatively. The radiological parameters presenting patellar positions, including the tibial slope, patellar convergence angle, and lateral tilt angle, did not change significantly between the preoperative values and the 2-year follow-up values. The mean patellar height significantly decreased (0.07 ± 0.14, p = 0.001 according to the Blackburn-Peel index and 0.32 ± 0.23, p < 0.001 using the modified Insall-Salvati ratio). The average tibial tubercle to trochlear groove (TT-TG) distance significantly decreased from 14.1 to 12.2 mm (p < 0.001). The Q angle also significantly decreased from 9.8o to 7.7o (p = 0.008). Chondral lesions of the patella and trochlear groove revealed significant deterioration; at 2 years after OWHTO, the arthritic grades of the PF joints worsened significantly, as determined by radiography (p = 0.007). Scintigraphic uptake in the PF joint was significantly lower (from 2 to 1) at 2 years postoperatively compared to that immediately after the index operation (p < 0.001). Only 4 of 56 (7.1%) patients showed increased uptake. Comparison between the improved and unimproved groups according to scintigraphic uptake changes revealed that the changes in the cartilage status on the patellar undersurface and TT-TG distance were the most significant predictive factors of increased scintigraphic uptake in the PF joint after OWHTO. CONCLUSION: Alignment correction by OWHTO result in PF compartment offloading and should be considered when identifying the surgical indications for OWHTO. LEVEL OF EVIDENCE: Therapeutic, Level IV.

Early medial reconstruction combined with severely injured medial collateral ligaments can decrease residual medial laxity in anterior cruciate ligament reconstruction.

INTRODUCTION: This study aimed to describe an anatomic medial knee reconstruction technique for combined anterior cruciate ligament (ACL) and grade III medial collateral ligament (MCL) injuries and to assess knee function and stability restoration in patients who underwent primary MCL reconstruction compared with primary repair. METHODS: A total of 105 patients who had undergone anatomic ACL reconstruction between 2008 and 2017 were enrolled in this retrospective study and divided into two groups according to concomitant MCL ruptures. Group A included patients with isolated ACL ruptures without MCL injuries. Group B included patients with both ACL and MCL injuries, and it was subdivided into three groups according to the severity of the MCL injury and treatment modality: B-1, grade I or II MCL injury treated conservatively; B-2: grade III MCL injury treated by primary MCL repair; and B-3: grade III MCL injury treated by primary reconstruction. Knee stability was measured via Telos valgus radiography at 6-month and 2-year postoperative. The Lysholm score, Tegner activity level, Likert scales (satisfaction), and return to previous sports were evaluated at 2-year postoperative. RESULTS: At 6-month postoperative, there was no significant difference in medial laxity between the B-2 and B-3 groups. However, at 2-year postoperative, medial laxity were significantly higher both at 30° of flexion (5.2° versus 2.2°, p = 0.020) and at full extension (3.4° versus 1.1°, p < 0.001) in patients in B-2 group compared to those in B-3 group. There were no statistically significant differences between the two groups with respect to Lysholm scores, Tegner activity levels, Likert scales (satisfaction), and returning to previous sports at the 2-year follow-up. CONCLUSION: Primary medial reconstruction combined with severely injured MCL in ACL reconstruction may decrease residual medial laxity more than primary repair. LEVEL OF EVIDENCE: Retrospective observational study, IV.

Three-column subdivision for isolated posterolateral tibial plateau fractures and perspective surgical approaches.

BACKGROUND: This study aimed (1) to introduce a computed tomography (CT)-based classification of the posterolateral compartment of the tibial plateau based on the fibula and to propose the individualized surgical approaches for each zone; and (2) to determine the surgical approach based on the classification, that would achieve a safe and effective reduction and could improve postoperative clinical outcomes. METHODS: Eighteen cases of tibia plateau fracture involving the isolated posterolateral compartment in a single institution were retrospectively analyzed. The posterolateral compartment of the tibial plateau was segmented into three zones based on the fibular position and an individualized surgical approach was proposed for each zone. In anterior Zone I, surgical treatment was performed using an extended anterolateral approach and the patient was placed in the supine position; in middle Zone II, using the transfibular approach in the supine position; in posterior Zone III, using the posteromedial approach in the prone position. RESULTS: In all cases, anatomical articular reduction (intra-articular step off in CT images <2 mm) was achieved and maintained for the follow up period. The average mechanical medial proximal tibial angle was increased from 87.6° before surgery to 88.2° in the immediate postoperative period (P = 0.060), and maintained for the follow up period (mean 89.9° at 1-year follow up). At the 1-year follow up, the knee range of motion averaged 140° and the Lysholm knee function score was 95.0 points. CONCLUSION: An individualized surgical approach and fixation according to three-zone subdivision for isolated posterolateral tibial plateau fractures provided an effective and safe method to treat posterolateral tibial plateau fractures.

Clinical Comparison of Medial Patellofemoral Ligament Reconstruction With or Without Tibial Tuberosity Transfer for Recurrent Patellar Instability.

BACKGROUND: No clear guidelines or widespread consensus has defined a threshold value of tibial tuberosity-trochlear groove (TT-TG) distance for choosing the appropriate surgical procedures when additional tibial tuberosity osteotomy (TTO) should be added to augment medial patellofemoral ligament (MPFL) reconstruction for recurrent patellar instability. PURPOSE: To compare the clinical outcomes between MPFL reconstruction and MPFL reconstruction with TTO for patients who have patellar instability with a TT-TG distance of 15 to 25 mm. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We retrospectively analyzed 81 patients who underwent surgical treatment using either MPFL reconstruction or MPFL reconstruction with TTO for recurrent patellar instability with a TT-TG distance of 15 to 25 mm; the mean follow-up was 25.2 months (range, 12.0-53.0 months). The patients were divided into 2 groups: isolated MPFL reconstruction (iMPFL group; n = 36) performed by 2 surgeons and MPFL reconstruction with TTO (TTO group; n = 45) performed by another 2 surgeons. Clinical outcomes were assessed using the Kujala score, Knee injury and Osteoarthritis Outcome Score, and Tegner activity score. Radiological parameters, including patellar height, TT-TG distance, patellar tilt, and congruence angle were compared between the 2 groups. Functional failure based on clinical apprehension sign, repeat subluxation or dislocation, and subjective instability and complications was assessed at the final follow-up. We also compared clinical outcomes based on subgroups of preoperative TT-TG distance (15 mm ≤ TT-TG ≤ 20 mm vs 20 mm < TT-TG ≤ 25 mm). RESULTS: All of the clinical outcome parameters significantly improved in both groups at the final follow-up (P < .001), with no significant differences between groups. The radiological parameters also showed no significant differences between the 2 groups. The incidence of functional failure was similar between the 2 groups (3 failures in the TTO group and 2 failures in the iMPFL group; P = .42). In the TTO group, 1 patient experienced a repeat dislocation postoperatively and 2 patients had subjective instability; in the iMPFL group, 2 patients had subjective instability. The prevalence of complications did not differ between the 2 groups (P = .410). In the subgroup analysis based on TT-TG distance, we did not note any differences in clinical outcomes between iMPFL and TTO groups in subgroups of 15 mm ≤ TT-TG ≤ 20 mm and 20 mm < TT-TG ≤ 25 mm. CONCLUSION: MPFL reconstruction with and without TTO provided similar, satisfactory clinical outcomes and low redislocation rates for patients who had patellar instability with a TT-TG distance of 15 to 25 mm, without statistical difference. Thus, our findings suggest that iMPFL reconstruction is a safe and reliable treatment for patients with recurrent patellar dislocation with a TT-TG distance of 15 to 25 mm, without the disadvantages derived from TTO.

Application of Three-Dimensional Computed Tomography Improved the Interrater Reliability of the AO/OTA Classification Decision in a Patellar Fracture.

We investigated whether interrater reliabilities of the AO/OTA classification of patellar fracture change with the imaging modalities applied, including plain radiography and two- and three-dimensional (2-D and 3-D) computed tomography (CT). Seven orthopedic specialists and four orthopedic residents completed a survey of 50 patellar fractures to classify the fractures according to the AO/OTA classification for patellar fractures. Initially, the survey was conducted using plain radiography only, then with 2-D CT introduced three weeks later and 3-D CT introduced six weeks later. Fleiss' Kappa coefficients were calculated to determine interrater reliability. The overall interrater reliability of the AO/OTA classifications was 0.40 (95% CI, 0.38-0.42) with plain radiography only and 0.43 (95% CI, 0.41-0.45) with the addition of 2-D CT. With the addition of 3-D CT, the reliability was significantly improved to 0.54 (95% CI, 0.52-0.56). In specialists, interrater reliability of the classifications was moderate with all three imaging modalities. With the use of 3-D CT, interrater reliability of the classification was 0.53 (95% CI, 0.50-0.56), which was significantly higher than that with the use of 2-D CT (κ = 0.45; 95% CI, 0.42-0.48). In residents, interrater reliability of the classification was 0.30 (95% CI, 0.24-0.36) with plain radiography. The reliability improved to 0.49 (95% CI, 0.43-0.56) with the addition of 2-D CT, which was significantly higher than that with plain radiography only. The use of 3-D CT imaging improved interrater reliability of the classification. Therefore, surgeons, especially residents, may benefit from using 3-D CT imaging for classifying and planning the treatment of patellar fractures.

Clinical outcomes of osteosynthesis of well-fixed periprosthetic proximal tibial fractures (Felix type 2A) after total knee arthroplasty.

AIMS: This study aimed to evaluate the clinical and radiologic outcomes of well-fixed periprosthetic tibial fractures after TKA. PATIENTS AND METHODS: The medical records of patients who presented with Felix type 2A periprosthetic tibial fractures after TKA between March 2015 and February 2020 were retrospectively obtained from 5 institutions. Data on injury mechanism, fracture pattern including open fractures and Felix classification, and surgical method were recorded. Functional outcomes including range of motion (ROM) and Knee Society Score (KSS) at postoperative 1 year were reviewed. The need for reoperation was also reviewed. Radiologic findings included union time and mechanical proximal tibial angle (MPTA) at the last radiologic follow-up. RESULTS: Eighteen patients (13 women, 5 men; average age, 73.9 years) were included. The average follow-up duration was 20.8 months. The fractures resulted from high-energy (11 cases) and low-energy (7 cases) injuries. Two cases involved open fractures. Anatomical locking plates were used in all cases: single plate (4 cases) and dual plates (14 cases). The average number of proximal screws was 7.1 (range, 4-9). All patients achieved bone union at an average of 18.6 weeks without secondary intervention. No infection occurred; however, 1 patient with skin necrosis required local flap. Implant removal was performed in 5 cases: 1 case, skin defect and 4 cases, discomfort due to plate prominence. The average ROM and KSS were 120.3° and 85.9, respectively. The mean MPTA was 87.8°; the MPTA was higher in the single-plate group (94.0° vs. 88.1°, p=0.013). Three cases involved values beyond the normal MPTA range (85-90°): 104° and 96° with a single plate and 92° with dual plates. The malalignment rate was higher in the single-plate group (p=0.043). CONCLUSION: Felix type 2A periprosthetic tibial fractures treated with minimally invasive osteosynthesis showed excellent clinical outcomes, and tibial alignment was well maintained in the dual-plate group.

Triaging deep vein thrombosis using ultrasonography after lower-extremity orthopedic surgery: analysis of a single-center experience.

PURPOSE: This study aimed to stratify risk factors and vein levels for postoperative deep vein thrombosis (DVT) after lower-extremity orthopedic surgery. METHODS: Ninety-nine patients who underwent Doppler ultrasonography after lower-extremity orthopedic surgery were enrolled. Medical records were reviewed for anesthesia duration, type of surgery, body weight, height, and cardiovascular risk factors (including history of smoking, diabetes mellitus or hypertension, blood pressure, and total cholesterol and high-density lipoprotein [HDL] cholesterol levels), and the DVT treatment. Ultrasound diagnosis of DVT was made according to a routine protocol. The relationships between selected factors and the presence of DVT were assessed using univariate and multivariate regression analyses. RESULTS: Thirty-three (33%) patients were found to have calf DVT. The mean age, weight, and height of the non-DVT and postoperative DVT patients were 55.1 years versus 65.4 years, 70.5 kg versus 61.2 kg, and 163.3 cm versus 157.0 cm, respectively. Total cholesterol/HDL levels in the non-DVT and DVT patients were 70.6/20.7 mg/dL and 90.8/26.0 mg/dL, retrospectively. Systolic and diastolic blood pressure in the non-DVT and DVT patients were 133.6/80.2 mm Hg and 132.2/78.1 mmHg, respectively. The mean duration of anesthesia was 173.9 versus 199.9 minutes, and the operative time was 136.4 minutes versus 161.0 minutes. Older age (P=0.005) and lower body weight (P=0.002) were significantly associated with postoperative DVT. No other significant between-group differences were found (P>0.05). The patients with ultrasound-identified DVT received antithrombotic treatment. None of them had distant thromboembolism. CONCLUSION: After lower-extremity orthopedic surgery, the calf veins in elderly patients with low body weight are susceptible to thrombosis; they would most likely benefit from postoperative ultrasonography.

Relationship of Bone Mineral Density and Knee Osteoarthritis (Kellgren-Lawrence Grade): Fifth Korea National Health and Nutrition Examination Survey.

BACKGROUND: Osteoarthritis (OA) and osteoporosis (OP) are the 2 most common bone disorders associated with aging. We can simply assume that older patients have a higher incidence of OA and OP with more severity. Although several papers have conducted studies on the relationship between OA and OP, none of them has demonstrated a conclusive link. In this study, we used radiological knee OA and bone mineral density (BMD; T-score of the total hip and lumbar spine) to analyze the incidence of OA and OP in a large population. We aimed to determine the relationship between OA and OP and investigate the associated risk factors. METHODS: This cross-sectional study used data extracted from the 2010-2012 Korea National Health and Nutrition Examination Survey. We evaluated a total of 4,250 participants aged ≥ 50 years who underwent knee radiography and dual-energy X-ray absorptiometry and their laboratory results. The relationship between radiological knee OA and BMD was assessed. The generalized linear model was used to evaluate the relationship between BMD and Kellgren-Lawrence (KL) grade. RESULTS: The higher KL grade was associated with older age, higher body mass index (BMI), female sex, and lower hemoglobin level (p < 0.001). No significant association was found between OA and the following variables: white blood cell, platelet, total cholesterol, vitamin D, alkaline phosphatase, parathyroid hormone, hypertension, diabetes, asthma, dyslipidemia, smoking status, alcohol consumption, and regular exercise (p > 0.05). After adjusting for confounding factors (age, BMI, diabetes, hypertension, smoking, and alcohol consumption), the average T-scores of total hip and lumbar spine were the highest in the mild OA group with KL grade 2 (-0.22 ± 1.08 and -0.89 ± 1.46, respectively, p < 0.001). The average T-scores of the total hip and lumbar spine significantly decreased as OA progressed from moderate (KL grade 3; -0.49 ± 1.05 and -1.33 ± 1.38, respectively, p < 0.001) to severe (KL grade 4; -0.73 ± 1.13 and -1.74 ± 1.75, respectively, p < 0.001). T-scores of the moderate-to-severe OA group were significantly lower than those of the non-OA group (KL grades 0 and 1, p < 0.001). CONCLUSIONS: Compared with the non-OA group, BMD (T-scores of the total hip and lumbar spine) was higher in the mild OA group and lower in the moderate-to-severe OA group.

Clinical efficacy of adductor canal block in medial open wedge high tibial osteotomy.

BACKGROUND: To evaluate the effect of adductor canal block (ACB) on short-term postoperative outcomes in patients who underwent medial open-wedge high tibial osteotomy (MOWHTO) compared to that of a placebo. METHODS: 35 patients who underwent unilateral MOWHTO between 2017 and 2019 were prospectively reviewed and randomly divided into two groups: 19 patients who received a single-shot ACB and 16 patients who received a saline injection (a placebo group). Primary outcomes were (1) pain measured using the visual analog scale and range of motion, (2) patient satisfaction, (3) postoperative need for additional opioids, (3) quadriceps strength (the time to straight leg raising [SLR]), (4) clinical outcomes, and (5) complications. RESULTS: The pain score was lower in the ACB group than in the placebo group in the first 12 h (p = 0.04). ACB did not exhibit significantly less quadriceps strength weakness postoperatively. There was no statistical difference in the time to SLR (23.5 ± 17.7 h in ACB vs. 27.6 ± 11.4 in placebo, p = 0.520). The opioid consumption rate within postoperative 12 h was significantly decreased after ACB (16.7% in ACB, 70% in placebo, p = 0.017). The proportion of patients with more than 5 opioid injections within 72 h postoperatively was lower in the ACB group (8.3% in ACB, 50% in placebo, p = 0.043). Both groups did not show any localized and systemic complications. CONCLUSION: ACB following MOWHTO exhibited better outcomes than a placebo with respect to opioid consumption with no changes in the quadriceps strength and complications. LEVEL OF EVIDENCE: II, Prospectively comparative study.

Machine-learning algorithm that can improve the diagnostic accuracy of septic arthritis of the knee.

PURPOSE: Prompt diagnosis and treatment of septic arthritis of the knee is crucial. Nevertheless, the quality of evidence for the diagnosis of septic arthritis is low. In this study, the authors developed a machine learning-based diagnostic algorithm for septic arthritis of the native knee using clinical data in an emergency department and validated its diagnostic accuracy. METHODS: Patients (n = 326) who underwent synovial fluid analysis at the emergency department for suspected septic arthritis of the knee were enrolled. Septic arthritis was diagnosed in 164 of the patients (50.3%) using modified Newman criteria. Clinical characteristics of septic and inflammatory arthritis were compared. Area under the receiver-operating characteristic (ROC) curve (AUC) statistics was applied to evaluate the efficacy of each variable for the diagnosis of septic arthritis. The dataset was divided into independent training and test sets (comprising 80% and 20%, respectively, of the data). Supervised machine-learning techniques (random forest and eXtreme Gradient Boosting: XGBoost) were applied to develop a diagnostic model using the training dataset. The test dataset was subsequently used to validate the developed model. The ROC curves of the machine-learning model and each variable were compared. RESULTS: Synovial white blood cell (WBC) count was significantly higher in septic arthritis than in inflammatory arthritis in the multivariate analysis (P = 0.001). In the ROC comparison analysis, synovial WBC count yielded a significantly higher AUC than all other single variables (P = 0.002). The diagnostic model using the XGBoost algorithm yielded a higher AUC (0.831, 95% confidence interval 0.751-0.923) than synovial WBC count (0.740, 95% confidence interval 0.684-0.791; P = 0.033). The developed algorithm was deployed as a free access web-based application ( www.septicknee.com ). CONCLUSION: The diagnosis of septic arthritis of the knee might be improved using a machine learning-based prediction model. LEVEL OF EVIDENCE: Diagnostic study Level III (Case-control study).

Change of joint-line convergence angle should be considered for accurate alignment correction in high tibial osteotomy.

BACKGROUND: The alignment correction after high tibial osteotomy (HTO) is made both by bony correction and soft-tissue correction around the knee. Change of the joint-line convergence angle (JLCA) represents the soft-tissue correction after HTO, which is the angle made by a tangential line between the femoral condyles and the tibial plateau. We described the patterns of JLCA change and related factors after HTO and investigated the appropriate preoperative planning method. METHODS: Eighty patients who underwent HTO between 2013 and 2016 were included for this retrospective study. Standing, whole-limb radiograph, supine knee anteroposterior (AP) and lateral were measured on the preoperative and postoperative radiographs. The patterns of JLCA changes and related factors were analyzed. RESULTS: JLCA decreased by a mean of 0.9° ± 1.2° (P < 0.001) after HTO. Sixteen patients (20%, group II) showed a greater JLCA decrease ≥ 2°, while 64 (80%, group I) patients remained in a narrow range of JLCA change < 2°. Group II showed more varus deformity (varus 8.1° vs. varus 4.7° in the mechanical femorotibial angle, P < 0.001), greater JLCA on standing (4.9° vs. 2.1°, P < 0.001), and the difference of JLCA in the standing and supine positions (2.8° vs. 0.7°, P < 0.001) preoperatively compared to group I. The risk of a greater JLCA decrease ≥ 2° was associated with greater preoperative JLCA in the standing position and the difference between the JLCA in the standing and supine positions. Postoperative JLCA correlated better with preoperative JLCA in the supine position than those in the standing position. A preoperative JLCA ≥ 4° or the difference of preoperative JLCA in the standing and supine positions ≥ 1.7° was the cut-off value to predict a large JLCA decrease ≥ 2° after HTO in the receiver operating characteristic (ROC) curve analysis. CONCLUSIONS: Surgeons should consider the effect of the JLCA change during the preoperative planning and intraoperative procedure to avoid unintended overcorrection.

Patellar fractures in elderly patients: a multicenter computed tomography-based analysis.

INTRODUCTION: This study aimed to demonstrate the characteristics of patellar fractures and evaluate clinical outcomes in elderly patients. PATIENTS AND METHODS: Medical records of patients aged ≥ 60 years who presented with patellar fractures were retrospectively reviewed from an institutionally approved multicenter (five institutions) orthopedic database. Patient characteristics and fracture patterns were identified, and the clinical outcomes were investigated. We compared differences according to the injury mechanism (low- vs. high-energy). RESULTS: A total of 202 patients [mean age, 69.4 years (range, 60-88 years); male, 89, female, 113] were included in this study. The mean follow-up period was 14.8 months (range 6-58 months), and 75% of the fractures were from low-energy injuries. According to the AO /OTA classification, the most common type was type C (136 cases, 67.3%; 33 cases, C1; 23, C2; and 80, C3), followed by type A (39 cases), type B (26 cases), and unclassified (1 case). The unclassified case was an intra-articular marginal impaction without cortical breakage. Computed tomography (CT) revealed that of the cases, 66.8% had an inferior pole involvement; 80.7%, a comminuted fragment; and 10.4%, an impacted fracture. A total of 166 fractures (82.2%) were treated surgically. The mean union time and range of motion were 13.1 weeks and 123.8° (range 30-150°), respectively. The Lysholm score was 82.1 ± 12.0, with 65.7% of the cases having excellent or good function. The complication rate was 12.4% (24 cases), including ten, four, two, and five cases of infection, fixation failure, nonunion, malunion, and pin migration, respectively. The reoperation rate was 26.4%. CONCLUSION: Patellar fractures in the elderly were mostly from low-energy injuries, and types C3 and A1 were the most common. CT images demonstrated high rates of an inferior pole involvement and comminution. The complication and reoperation rates were relatively high.

Beyond Lipid Signaling: Pleiotropic Effects of Diacylglycerol Kinases in Cellular Signaling.

The diacylglycerol kinase family, which can attenuate diacylglycerol signaling and activate phosphatidic acid signaling, regulates various signaling transductions in the mammalian cells. Studies on the regulation of diacylglycerol and phosphatidic acid levels by various enzymes, the identification and characterization of various diacylglycerol and phosphatidic acid-regulated proteins, and the overlap of different diacylglycerol and phosphatidic acid metabolic and signaling processes have revealed the complex and non-redundant roles of diacylglycerol kinases in regulating multiple biochemical and biological networks. In this review article, we summarized recent progress in the complex and non-redundant roles of diacylglycerol kinases, which is expected to aid in restoring dysregulated biochemical and biological networks in various pathological conditions at the bed side.

The effect of interleukin-8 in the early stage after anterior cruciate ligament reconstruction with remnant preservation.

PURPOSE: We studied the effect of interleukin-8 (IL-8) as the factor for angiogenesis in the joint fluid of remnant-preserved anterior cruciate ligament reconstruction (RP-ACLR). MATERIALS AND METHODS: We measured 12 cytokines in joint fluid by multiplex assay and assessed the relationship between IL-8 and vascular endothelial growth factor (VEGF) concentrations. The signal intensity and mean sagittal diameter via postoperative magnetic resonance imaging (MRI) scans were evaluated and the stress X-ray image was analyzed at 3, 6, and 12 months after operation. RESULTS: The IL-8 concentration was highest 3 months postoperatively in those patients who underwent RP-ACLR. Clinical data also showed that the signal intensity and stress radiography of the knee graft were significantly better at the early postoperative stage. DISCUSSION: Our results show that IL-8 plays an important role in angiogenesis within 3 months after RP-ACLR. This effect yields better recovery after operation. RP-ACLR patients with high knee stability in clinical data were identical to those with high expression of IL-8 in experimental data. Therefore, IL-8 has been shown to help revascularization and ligamentization of the grafted tendon. These results indicate that IL-8 in RP-ACLR is an important factor for angiogenesis after operation. Unfortunately, the relationship of IL-8 and VEGF in vivo has not been studied. CONCLUSION: Our results showed that the IL-8 concentration was very high within 3 months after RP-ACLR operation. The increase in concentration of IL-8 over time was consistent with the increase in VEGF concentration. In the IL-8 clinical setting, MRI analysis showed that ACL synovialization and tension were better in patients who underwent the remnant preservation method. In addition, it was shown that RP-ACLR may be advantageous for early anterior stability within 1 year post operation and beneficial for tendon graft in the early stage post operation. Taken together, our findings suggest that IL-8 may contribute to angiogenesis which is helpful for revascularization and ligamentization of the graft tendon in the early stages of RP-ACLR.

The risk of concomitant injuries of the contralateral side in valgus injured knee by lateral bumper impact - "Windswept injury mechanism".

PURPOSE: Valgus injury of high energy of the lateral bumper impact can lead blows to the inside of the knee that push the knee outwards or indirect injury where a varus force is applied to the contralateral knee, which injury pattern named as "Windswept injury mechanism" in this study. The objective of this study was to establish injury pattern in the contralateral side knee on the basis of this pattern recognition to enhance a diagnosis of interrelated osseous and soft-tissue injuries. METHODS: Sixteen patients by "Windswept injury mechanism" were identified, who visited a level 1 trauma center between Jan 2007 and Dec 2016. We first evaluated the osseous and soft tissue injuries at primary impacted site by valgus force after checking MRI. Thereby, assessed the contralateral knee which structures were injured. To find any correlation between both knees in ligament injuries, patients were divided into two groups according to coincided anterior cruciate ligament (ACL) rupture. RESULTS: By the "Windswept injury mechanism", MCL total rupture was observed in all primary knees, and the major ligament injuries also were coincided on the contralateral knee. In primary knee, either ACL or PCL was ruptured in all cases. 9 patients (56%) had combined ACL rupture with MCL injury, 12 patients (75%) of combined PCL injury, and 5 patients (31%) had combined injury of both ACL and PCL. In contralateral knee, lateral collateral ligament injury was observed in 69%. 7 patients (44%) was combined with ACL injury, 7 patients (44%) with combined PCL injury, 4 patients (25%) with combined both ACL and PCL injury. In comparison of two groups, significantly higher risk of ACL injury in the contralateral knee was identified when coincided ACL and MCL injury in primary knee (p = 0.003). CONCLUSION: The specific mechanism-based injury pattern of "Windswept injury mechanism" was the first to identify the mechanism that showed concomitant major ligament injuries in the contralateral knee and to develop validated the higher risk of ACL injury in the contralateral knee when combined ACL and MCL injuries in primary knee, which improving diagnosis of potentially subtle and easily missed knee injuries.

Miniplate osteosynthesis in fracture surgeries: Case series with review of concepts.

PURPOSE: Miniplates were initially developed as targets for foot and hand fractures, but they have been used in the treatment of fixation of small bone fragments, reduction of long bone fractures and non-union treatment, which have been difficult to treat. In this study, the authors used miniplates to treat fractures of the upper extremities, lower extremities, and pelvis obtained good outcomes. Herein, the authors report these good outcomes and review the current concept of miniplates. PATIENTS AND METHODS: Forty-two patients treated with miniplates between March 2012 and March 2017 who attended follow-up for > 1 year were included in this retrospective study. Miniplates were selected according to purpose, which was classified into three categories: fixation, reduction, and stability enhancement. For fixation, miniplates were used to fix distal fibular fractures occurring distal to the syndesmosis and treat patellar and olecranon fractures with severe comminution. For reduction, miniplates were used to reduce the tibia during intramedullary nailing in tibiofibular shaft fractures, while reduction was performed in advance of definitive plating fixation in patients with humeral and pelvic fractures. To enhance stability, the miniplate was inserted after autobone graft for atrophic nonunion at the humeral shaft following nail insertion. The validity of a miniplate was analyzed by reviewing the published literature on the use of miniplates in orthopedic fracture surgeries. RESULTS: Bony union was achieved in all cases. No specific postoperative complications were observed; however, mild pain and limited range of motion observed in two patients were resolved after implant removal. Sixteen studies on fracture treatment using miniplates reported clinically fair outcomes. CONCLUSION: Miniplates are not just small metal plates. Depending on the location and treatment of the fracture, the miniplate can effectively fix small bone fragments, help the main plate to maintain the reduction of large bone fragments, and increase the fixation force for nonunion treatment.

Intraoperative assessment of reduction quality during nail fixation of intertrochanteric fractures.

BACKGROUND: The quality of intertrochanteric fracture reduction has traditionally been evaluated using simple radiographs. However, subjective intraoperative evaluation and efforts to achieve a perfect reduction are essential for optimal outcomes. This study aimed to establish criteria for the intraoperative assessment of the quality of intertrochanteric fracture reduction and also analyzed postoperative outcomes in terms of reduction quality. METHODS: This study included 106 patients who received cephalo-medullary nailing for the treatment of intertrochanteric fractures between March 2012 and May 2016 and were followed-up for at least 1 year. An image intensifier was used intraoperatively to evaluate reduction quality by examining the restoration of anteromedial cortex continuity, and neck-shaft angle and anteversion. Based on the reduction quality, the patients were classified into optimal, acceptable, and unacceptable groups, with intervention provided for the unacceptable group. The need for revision surgery and the degree of blade sliding were assessed, and postoperative outcomes related to implant position were analyzed. RESULTS: Over 50% of patients with Arbeitsgemeinschaft für Osteosynthesefragen/Orthopaedic Trauma Association (AO/OTA) type 31A2 and A3 fractures were assigned to the unacceptable group after closed reduction (P = 0.006), and 60 cases required additional reduction. Approximately 40% of cases classified as clinically unacceptable required revision, and the rate of sliding was ≥2-fold higher in the unacceptable group than those in the optimal and acceptable groups (P = 0.015), with an average excessive sliding of 9.85 mm. Regarding implant position, cut-out or penetration were observed in cases with superiorly-located blades (P = 0.039). CONCLUSIONS: Good outcomes cannot be achieved with traction alone for femoral intertrochanteric fractures. Active management is required because accurate anteromedial cortex reduction, and restoration of neck-shaft angle and anteversion are essential in femoral intertrochanteric fractures.