Osteotomy configuration of the proximal wedge and analysis of the affecting factors in the medial open-wedge high tibial osteotomy.

PURPOSE: The purposes of this study were (1) to confirm the disparity of the measured thickness at the lateral hinge between anterior-posterior (AP) radiograph and 3D CT image, (2) to evaluate the affecting factors, and (3) to evaluate the differences between uniplanar and biplanar osteotomies. METHODS: From 2012 to 2014, a prospective comparative study was performed with 30 patients who received uniplanar osteotomy (group I) and 35 patients who received biplanar osteotomy (group II). For measurement of the proximal wedge, postoperative AP radiograph and 3D CT images were used. In the AP radiograph, medial and lateral bony bridge thicknesses were measured. In the 3D CT, the anterior and posterior images parallel to the coronal plane were selected for the evaluation. Coronal osteotomy slope was measured with the anterior image of the 3D CT scan. Sagittal osteotomy slope was measured with the sagittal section of the CT scan. RESULTS: Differences between the lateral bony bridge thicknesses measured in AP radiograph and the posterolateral posterolateral bony bridge thicknesses measured in 3D CT were statistically significant in both groups. Negative correlation was observed in the biplanar osteotomy group. Differences of the sagittal osteotomy slope from the native tibial slope showed negative correlation in the biplanar osteotomy group. CONCLUSION: Thickness of the posterolateral bony bridge was smaller compared to the observed thickness on the AP radiograph image that is routinely used for the follow-up. The thickness would be getting smaller if osteotomy is performed with an abrupt angle on the coronal plane and reverse slope on the sagittal plane. Therefore, osteotomy with abrupt angle on the coronal plane and reverse slope on the sagittal plane should be avoided for the proper thickness of the posterolateral bony bridge. LEVEL OF EVIDENCE: III.

Effect of the Osteotomy Length on the Change of the Posterior Tibial Slope With a Simple Distraction of the Posterior Gap in the Uni- and Biplanar Open-Wedge High Tibial Osteotomy.

PURPOSE: To (1) determine the length of the osteotomy at the anterior and posterior cortex, (2) compare between uni- and biplanar osteotomy, and (3) evaluate the relationship between the extent of the osteotomy and change of the posterior tibial slope. METHODS: A prospective comparative study of 24 uniplanar and 30 biplanar osteotomies was performed. To evaluate the length of osteotomy, osteotomy lines of the anterior and posterior cortex were analyzed in the 3-dimensional surface models. For slope measurement, the intramedullary axis of the proximal tibia (slope P), posterior cortical line of the proximal tibia (slope C), and anterior cortical line of the proximal fibula (slope F) were used. An analysis of the changes in the posterior tibial slope was performed independently using a pre- and postoperative lateral plane radiograph. RESULTS: In the uniplanar osteotomy, ratios of the osteotomized length to the total cortical length aligned with the osteotomized plane were larger in the anterior cortex (0.91 in uniplanar v 0.46 in biplanar; P = 0) and posterior cortex (0.97 in uniplanar v 0.79 ratio in biplanar; P = 0). Furthermore, the posterior tibial slope was maintained in both groups and the ratios between the anterior and posterior gap in both groups were 0.57 and 0.63, respectively. The maintenance of the slope was not related to any specific variables. Additionally, these phenomena did not differ between those patients who underwent uni- and those who underwent biplanar osteotomy. CONCLUSIONS: Increase in the posterior tibial slope was prevented with appropriate uni- or biplanar osteotomy with a simple distraction at the most posterior gap. However, in the uniplanar osteotomy, the ratio of the osteotomized length to the total cortical length was larger in both the anterior and posterior cortex.

Analysis of Longitudinal Outcome Data with Missing Values in Total Knee Arthroplasty.

We sought to determine the influence of missing data on the statistical results, and to determine which statistical method is most appropriate for the analysis of longitudinal outcome data of TKA with missing values among repeated measures ANOVA, generalized estimating equation (GEE) and mixed effects model repeated measures (MMRM). Data sets with missing values were generated with different proportion of missing data, sample size and missing-data generation mechanism. Each data set was analyzed with three statistical methods. The influence of missing data was greater with higher proportion of missing data and smaller sample size. MMRM tended to show least changes in the statistics. When missing values were generated by 'missing not at random' mechanism, no statistical methods could fully avoid deviations in the results.

Prevalence and Risk Factors of Spine, Shoulder, Hand, Hip, and Knee Osteoarthritis in Community-dwelling Koreans Older Than Age 65 Years.

BACKGROUND: Osteoarthritis (OA) is common and disabling among older patients around the world. Data exploring the prevalence and risk factors of OA are of paramount importance in establishing healthcare policies. However, few studies have evaluated these topics among Asian populations. QUESTIONS/PURPOSES: This study was conducted to determine the prevalence and risk factors of radiographic OA in the spine, shoulder, hand, hip, and knee in Koreans older than age 65 years. METHODS: A simple random sample (N = 1118) was drawn from a roster of elderly individuals older than age 65 years in Seongnam. Of the 1118 invited subjects, 696 (males = 298, females = 398) participated in this study (a response rate of 62%). The mean age of respondents was 72 ± 5 years (range, 65-91 years). Radiographs of the lumbar spine, shoulder, hand, hip, and knee were taken and afterward evaluated for radiographic OA. The Kellgren-Lawrence grading system was used for all mentioned joints, and radiographic OA was defined as Grade 2 changes or higher. The association of sex, aging, and obesity with OA in each of the mentioned joints was determined with the help of multivariate logistic regression. RESULTS: The highest prevalence of radiographic OA was seen in the spine (number of subjects with OA/number of whole population = 462 of 696 [66%]) followed by the hand (415 of 692 [60%]), knee (265 of 696 [38%]), shoulder (36 of 696 [5%]), and hip (15 of 686 [2%]). Female sex was associated with knee OA (odds ratio [OR], 5.7; 95% confidence interval [CI], 3.9-8.4; p < 0.001) and hand OA (OR, 2.3; 95% CI, 1.6-3.1; p < 0.001), and male sex was associated with spine OA (OR, 0.7; 95% CI, 0.5-1.0; p = 0.025). Aging was associated with radiographic OA in the spine, knee, and hand (OR per 5-year increments, 1.3 [95% CI, 1.1-1.6; p = 0.001], 1.6 [95% CI, 1.4-1.9; p < 0.001], and 1.4 [95% CI, 1.2-1.7; p < 0.001]), respectively) but not associated with OA in the hip and shoulder. Obesity was associated with knee OA (OR, 3.4; 95% CI, 2.4-5.0; p < 0.001) and spine OA (OR, 1.5; 95% CI, 1.1-2.2; p = 0.014) but not with OA in other joints. CONCLUSIONS: OA of the spine, hand, and knee is likely to become a major public health problem rather than shoulder and hip OA in Korea. Associations of demographic factors with radiographic OA differed among each joint, and that would be valuable information to assess the role and influence of risk factors of OA in various joints. LEVEL OF EVIDENCE: Level III, prognostic study.

Functional Outcomes of a New Mobile-Bearing Ultra-Congruent TKA System: Comparison With the Posterior Stabilized System.

We determined whether a new mobile-bearing ultra-congruent (UC) TKA system provides better functional outcomes than an established posterior-stabilized (PS) prosthesis. The functional outcomes (motion arc, AKS scores, WOMAC Index, and SForm-36 scores evaluated at 1 and 2 years postoperatively), satisfaction and incidences of adverse events were compared between the knees implanted with mobile-bearing UC prosthesis (n=103) and the mobile-bearing PS prosthesis (n=99). At 2 years, mobile-bearing UC TKAs showed similar functional outcomes and satisfaction, but smaller motion arc compared to mobile-bearing PS TKAs (126° vs. 131°). There were no differences in the incidence of adverse events. Mobile-bearing UC prosthesis can be considered a safe and viable alternative to the PS design, with an expectation of smaller postoperative maximum flexion.

Clinical Implications of Femoral Anthropometrical Features for Total Knee Arthroplasty in Koreans.

Anthropometric features of Asians femora and their clinical relevance with regard to TKA are not rigorously investigated. We attempted to determine how well current prostheses accommodate femoral anthropometric features of Koreans and whether the presence of condylar or trochlear overhang or underhang adversely affects functional outcomes. We hypothesized that current prostheses do not accommodate Korean female femora well, and that overhang or underhang would adversely affect outcomes. Condylar and trochlear mediolateral (ML) widths and condylar anteroposterior (AP) heights were measured, and ML/AP ratios were calculated in 1025 osteoarthritic knees that underwent TKA. Besides gender difference, wide individual variation exists in condylar and trochlear widths and ML/AP aspect ratios for given AP heights. Size options of current prostheses could not cover the wide ranges of ML widths for given AP heights. The knees with condylar overhang more than 4mm showed lower maximum flexion angle postoperatively (P=0.005).

Culture-Expanded Autologous Adipose-Derived Mesenchymal Stem Cell Treatment for Osteonecrosis of the Femoral Head.

BACKGROUD: Outcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH. METHODS: Eighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint. RESULTS: Preoperatively, the necrotic lesion extent was 63.0% (38.4%-96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2). CONCLUSIONS: Our outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.

Same-Level Fracture of the Tibial Metal Tray and Polyethylene Insert After Total Knee Arthroplasty.

The authors report a case of failure fracture of the tibial metal tray and polyethylene insert at the same level in a 73-year-old woman 10 years after total knee arthroplasty using the AMK Total Knee System (DePuy, Warsaw, Indiana). Causes of this fracture are analyzed and discussed, with the focus on the importance of component design, position, and size. The overall aim of this case report is for orthopedic surgeons to avoid this complication in total knee arthroplasty by paying attention to these controllable factors. [Orthopedics. 2016; 39(4):e787-e789.].

Epidemiological characteristics of patellofemoral osteoarthritis in elderly Koreans and its symptomatic contribution in knee osteoarthritis.

BACKGROUND: Many studies have reported the prevalence of knee osteoarthritis (OA) but have invariably focused on the tibiofemoral (TF) joint and overlooked the patellofemoral (PF) joint. Accordingly, little epidemiological information is available regarding the PF OA. The purpose of the current study was to document the epidemiological characteristics of PF OA in elderly Koreans. METHODS: Radiographic assessment was performed for 681 elderly (≥65 years old) Koreans recruited from a community, and symptom severity was evaluated using Western Ontario and McMaster Universities Index (WOMAC) and Short Form-36 (SF-36) scales. Prevalence of different categories of knee OA (isolated PF OA, isolated TF OA and combined PF and TF OA) was calculated. The symptoms of isolated PF OA group and non-OA group were compared. RESULTS: The overall prevalence of OA was 22.0% in the PF compartment and 34.1% in the TF compartment. The prevalence of isolated PF OA, isolated TF OA, and combined PF and TF OA was 3.8%, 17.8%, and 19.2%, respectively. Female sex, aging, and obesity were not associated with isolated PF OA. No significant differences were found in any clinical outcome scales between the isolated PF and non-OA groups. CONCLUSION: This study documents that OA in the PF joint is common in elderly Koreans, but isolated PF OA is rare. Demographic risk factors are not associated with isolated PF OA, suggesting that isolated PF OA may have a different pathophysiology from other types of knee OA. Our study also indicates that the presence of isolated PF OA should not be construed to be responsible for clinical symptoms.

Effect of age on functional and structural outcome after rotator cuff repair.

BACKGROUND: There are numerous reports on the outcome of rotator cuff repair according to age. However, the results are conflicting and driven by univariate analysis, which is not free of confounding factors. HYPOTHESIS: Age does not affect the anatomical and functional outcomes of rotator cuff repair. STUDY DESIGN: Case series; Level of evidence, 4. MATERIALS AND METHODS: Eighty-one men and 96 women underwent rotator cuff repair at one institution and received computed tomography arthrography and functional evaluations at least 1 year after surgery. Various structural and clinical features according to age were evaluated. The correlation was assessed between age and outcomes, with adjustment for the preoperative score. RESULTS: Patient mean age was 60.0 +/- 8.7 years. The mean ages were higher in women, nonsmokers, and those with positive paradoxical abduction, lower level of sports activity, the presence of biceps injury, higher fatty degeneration in cuff muscles, inferior isokinetic muscle performance, bigger tear size, more retraction of tear, and symptomatic acromioclavicular arthritis. For the integrity of the repair, the mean age was higher in the retear group (31.1%) than in the intact group (68.9%)-that is, 63.7 +/- 7.5 and 58.4 +/- 8.7 years, respectively (P <.001). Only the Constant score exhibited a positive correlation with age after adjustment (P = .009). Univariate regression analysis revealed that a 0.313-point increment of Constant score could be expected for each year of age. CONCLUSION: On univariate analysis, older age was related with poor postoperative integrity and better functional improvement in Constant score. Multivariate regression revealed that age was not an independent determinant for anatomical or functional outcome whereas the tear retraction and fatty degeneration of the infraspinatus were independent factors for the integrity of repair and the presence of the paradoxical abduction and abduction torque of the unaffected shoulder for the Constant score.