Radiomic analysis of preoperative magnetic resonance imaging for the prediction of pituitary adenoma consistency.

BACKGROUND: The consistency of pituitary adenomas affects the course of surgical treatment. PURPOSE: To evaluate the diagnostic capabilities of radiomics based on T1-weighted (T1W) and T2-weighted (T2W) magnetic resonance imaging (MRI) in conjunction with two machine-learning (ML) techniques (support vector machine [SVM] and random forest classifier [RFC]) for assessing the consistency of pituitary adenomas. MATERIAL AND METHODS: The institutional database was retrospectively scanned for patients who underwent surgical excision of pituitary adenomas. Surgical notes were accepted as a reference for the adenoma consistency. Radiomics analysis was performed on preoperative coronal 3.0T T1W and T2W images. First- and second-order parameters were calculated. Inter-observer reproducibility was assessed with Spearman's Correlation (ρ) and intra-observer reproducibility was evaluated with the intraclass correlation coefficient (ICC). Least absolute shrinkage and selection operator (LASSO) was used for dimensionality reduction. SVM and RFC were used as ML methods. RESULTS: A total of 52 patients who produced 206 regions of interest (ROIs) were included. Twenty adenomas that produced 88 ROIs had firm consistency. There was both inter-observer and intra-observer reproducibility. Ten parameters that were based on T2W images with high discriminative power and without correlation were chosen by LASSO. The diagnostic performance of SVM and RFC was as follows: sensitivity = 95.580% and 92.950%, specificity = 83.670% and 88.420%, area under the curve = 0.956 and 0.904, respectively. CONCLUSION: Radiomics analysis based on T2W MRI combined with various ML techniques, such as SVM and RFC, can provide preoperative information regarding pituitary adenoma consistency with high diagnostic accuracy.

Bone marrow lesions of the femoral head: can radiomics distinguish whether it is reversible?

Purpose: Contrary to the self-limiting nature of reversible bone marrow lesions, irreversible bone marrow lesions require early surgical intervention to prevent further morbidity. Thus, early discrimination of irreversible pathology is necessitated. The purpose of this study is to evaluate the efficacy of radiomics and machine learning regarding this topic. Material and methods: A database was scanned for patients who had undergone MRI of the hip for differential diagnosis of bone marrow lesions and had had follow-up images acquired within 8 weeks after the first imaging. Images that showed resolution of oedema were included in the reversible group. The remainders that showed progression into characteristic signs of osteonecrosis were included in the irreversible group. Radiomics was performed on the first MR images, calculating first- and second-order parameters. Support vector machine and random forest classifiers were performed using these parameters. Results: Thirty-seven patients (seventeen osteonecrosis) were included. A total of 185 ROIs were segmented. Fortyseven parameters were accepted as classifiers with an area under the curve value ranging from 0.586 to 0.718. Support vector machine yielded a sensitivity of 91.3% and a specificity of 85.1%. Random forest classifier yielded a sensitivity of 84.8% and a specificity of 76.7%. Area under curves were 0.921 for support vector machine and 0.892 for random forest classifier. Conclusions: Radiomics analysis could prove useful for discrimination of reversible and irreversible bone marrow lesions before the irreversible changes occur, which could prevent morbidities of osteonecrosis by guiding the decisionmaking process for management.

The role of real-time elastosonography in the diagnosis of quadriceps fat pad edema.

BACKGROUND: Quadriceps fat pad edema (QFPE) is one of the causes of anterior knee pain. Real-time elastosonography (RTE) has been increasingly used in musculoskeletal disorders. PURPOSE: To evaluate the role of RTE in the diagnosis of QFPE. MATERIAL AND METHODS: A total of 23 patients with QFPE on magnetic resonance imaging (MRI) (study group) were prospectively compared with 29 patients with normal MRI findings (control group) using RTE. On MRI, the thickness of the quadriceps fat pad (QFP), and on RTE, strain ratio (SR) of QFP were measured and compared between the two groups. RESULTS: The study group contained 23 patients (12 men, 11 women; mean age = 41.6 ± 7.0 years) and the control group contained 29 patients (14 men, 15 women; mean age = 42.3 ± 6.1 years). No significant differences were found in terms of mean age and sex between the two groups (P = 0.70, P = 0.78, respectively). The median thicknesses of the QFPs were 8.10 mm and 6.75 mm in the study and control groups, respectively (P < 0.001). The median SR values of the study group and control group were found to be 63.20 and 6.24, respectively. The SR values were significantly higher in patients with QFPE (P < 0.001). CONCLUSION: RTE may be an effective imaging method for evaluating QFPE.

CT evaluation for sarcopenia involving the psoas and paravertebral muscles in patients with total hip arthroplasty.

BACKGROUND: Computed tomography (CT) has been validated in diagnosing sarcopenia in various clinical conditions. AIM: To evaluate the core abdominal muscles in terms of sarcopenia in patients with total hip arthroplasty (THA) with and without complication. METHODS: Retrospective analysis of patients with a pelvic CT revealed 145 consecutive patients with THA. Also, 118 consecutive cases with normal CT scans constituted the control group. The area and density measurements of bilateral psoas (PSA, psoas area; PSD, psoas density) and paravertebral (PVA, paravertebral area; PVD, paravertebral density) muscles were performed at the level of L3 or L4 vertebrae regardless of prosthesis side. All measurements were evaluated in normal cases and in patients with THA, as well as in patients with complicated prostheses. RESULTS: In the whole population and subgroup of patients with bilateral THA, bilateral PSA, PSD, and PVD but not the PVA were lower in patients with THA compared to controls (all p < 0.01). In patients with unilateral prostheses, ipsilateral PSA, PSD, and bilateral PVD but not the PVA were lower compared to controls (all p < 0.01). Furthermore, in patients with unilateral prostheses with complication, only ipsilateral PSD was lower compared to patients with unilateral prostheses without complication (all p < 0.05) and in patients with bilateral prostheses with complication, bilateral PSA, PSD, and PVD but not the PVA were lower compared to patients with bilateral prostheses without complication (all p < 0.05). CONCLUSION: Sarcopenia indicated by the area and density measurements of core abdominal muscles can be associated with the presence and complication of hip prostheses.

The incidence of congenital lumbosacral malformations in young male Turkish military school candidates population.

BACKGROUND: During routine radiological examinations of the lumbar spine, congenital anomalies such as lumbosacral transition vertebra and scoliosis are frequently encountered in asymptomatic patients. They are not always associated with pathologies but have the potential to cause back pain in later times. The aim of this study is to analyze the prevalence of lumbar vertebral abnormalities in a group of young military school candidates who had no prior complaints. METHODS: We retrospectively evaluated the direct radiographs of asymptomatic young men aged between 17 and 22 applying between July 2018 and August 2018, for the routine check-up before becoming military school students. Exclusion criteria were prior history of low back pain for any reason, sciatica, neurogenic claudication, history of prior spinal surgery and history of a concomitant rheumatologic disease. All radiographs were evaluated for total lumbar vertebra number, morphology, presence of lumbosacral transitional vertebrae (LSTV), spina bifida occulta (SBO) and presence of lumbar and/or lumbar-elongated scoliosis. RESULTS: All 3132 patients were male and mean age was 18.37. Out of them, 887 (28.3%) had a congenital lumbo-sacral anomaly that they were not aware of. The most common anomaly we detected was SBO, in 16.2% of the cases followed by LSTV with 12.9% of the cases. Some of the applicants had more than one anomaly in their X-rays. CONCLUSION: Correct identification of a lumbar abnormalities is of great importance, especially before surgical procedures. It is a known fact that most wrong-level spine surgery occurs in patients with variant spine anatomy, including LSTV. Meticulous screening and analyses should be performed to all patients scheduled for spinal surgery in order to avoid peri-operative complications and unwanted final results.

Which design tolerates rotational mismatch better in unicompartmental knee arthroplasty: fixed or mobile bearing?

Unicompartmental knee arthroplasty is an effective method for the treatment of medial compartment osteoarthritis. However, appropriate surgical tech- nique and optimum implant positioning are crucial for a satisfactory outcome. This study aimed to demonstrate the relation between the clinical scores and the alignment of the components in UKA. A total of 182 patients with medial compartment osteoarthritis and treated by UKA between January 2012 and January 2017 were enrolled in this study. Computed tomography (CT) was used to measure the rotation of components. Patients were divided into two groups according to the insert design. These groups were divided into three subgroups according to the angle of the tibia relative to the femur (TFRA) (A): TFRA 0° to 5° either internal or external rotation; (B): TFRA >5° internal rotation, and (C): TFRA >5° external rotation. There was no significant difference between the groups in terms of age, body mass index (BMI) and follow-up period. KSS scores increased as the tibial component rotation (TCR) external rotation increased, but there was no correlation for WOMAC score. (P: 0,039 r: 0,207; P:0,347 r:0,095, respectively) Post-operative KSS and WOMAC scores decreased as TFRA external rotation was increased. (p: 0,001; p:0,001, respectively) No correlation has been observed between femoral component rotation (FCR) internal rotation and post-operative KSS and WOMAC scores. (p: 0,261; p: 0,502, respectively) Any mismatch between the components is better tolerated by mobile-bearing designs compared to fixed-bearing designs. Orthopedic surgeons should take care of rotational mismatch of components, not only the axial alignment of the components.

Sonoelastography of the knee joint.

Magnetic resonance imaging (MRI) is generally the preferred method for assessing lesions of the knee cartilage and subchondral bone. There have been a few cartilage imaging studies using real-time elastosonography (RTE), which has increased in importance and range of use in recent years. The aim of this cadaveric study was to assess the efficacy of a new diagnostic method combining USG and RTE and also to perform intra-articular examinations together with arthroscopy. A total of 12 fresh unpaired human knees were examined. The laparoscopic ultrasound transducer was deployed using standard anteromedial and anterolateral arthroscopic portals. Iatrogenic defects were examined using mosaicplasty tools in healthy-looking areas of cartilage, and strain in those areas was measured using RTE. The median strain value of the pathological femoral cartilage region was significantly higher than that of the normal cartilage region (1.23 [0.71-2.24] vs. 0.01 [0.01-0.01], P = 0.002, respectively). Arthroscopic study of cartilage using RTE can be a guide for orthopedic surgeons and use of intra-articular probes could be universalized. Clin. Anat. 32:99-104, 2019. © 2018 Wiley Periodicals, Inc.

Significant associated MRI findings in patients with anterior cruciate ligament stump entrapment.

OBJECTIVE: Objective of this study was to determine the relationship between development of stump entrapment (SE) lesions and associated injuries in patients with knee extension deficits who underwent anterior cruciate ligament (ACL) reconstruction surgery. MATERIALS AND METHODS: This retrospective study included 79 patients who had an arthroscopy-proven ACL rupture causing knee extension loss. Presence and type of the SE lesions, injuries of collateral-cruciate ligaments and bones, and tears of the menisci were evaluated and recorded on magnetic resonance imaging. RESULTS: The SE lesions were significantly more common in patients who had compressive posterior lateral tibial plateau fractures, tibia medial plateau edema and medial collateral ligament (MCL) injuries compared to the patients without stump lesions (p < 0.05). Posterior cruciate ligament (PCL) partial tears or sprains were significantly more common in patients with SE 1 lesions compared to the patients with SE 2 lesions (OR = 6.72; 95 % CI: 1.56-28.93). CONCLUSION: SE is significantly more common in patients with compressive posterior lateral tibial plateau fractures, tibia medial plateau edemas and MCL injuries. PCL injury is more common in patients with type 1 SE.

Foetal biometry in polyhydramnios: Does femur length fall behind?

We aimed to identify the growth patterns in polyhydramnios, and therefore evaluated 108 singleton pregnancies complicated with polyhydramnios according to the changes in biparietal diameter (BPD), abdominal circumference (AC) and femur length (FL) percentiles. The pregnancy outcomes according to the growth features were analysed. In the study population, BPD and AC percentiles exhibited a significant increase (p = 0.023 and 0.05, respectively), although FL percentiles showed a significant decrease (p = 0.006) according to the changes in third trimester relative to second trimester. In the overgrown group (n = 52), the FL/BPD ratio was lower (p < 0.001), with more foetuses with FL/BPD ratios below 71 (p = 0.05). In conclusion, there was a significant increase in BPD and AC percentiles and a decrease in FL percentiles in third trimester relative to second trimester in foetuses with polyhydramnios. However, we observed a shorter FL and a lower FL/BPD ratio without associated skeletal dysplasia in overgrown foetuses.

Strain ratio measurement of femoral cartilage by real-time elastosonography: preliminary results.

OBJECTIVE: The purpose of this study was to evaluate strain ratio measurement of femoral cartilage using real-time elastosonography. METHODS: Twenty-five patients with femoral cartilage pathology on MRI (study group) were prospectively compared with 25 subjects with normal findings on MRI (control group) using real-time elastosonography. Strain ratio measurements of pathologic and normal cartilage were performed and compared, both within the study group and between the two groups. RESULTS: Elastosonography colour-scale coding showed a colour change from blue to red in pathologic cartilage and only blue colour-coding in normal cartilage. In the study group, the median strain ratio was higher in pathologic cartilage areas compared to normal areas (median, 1.49 [interquartile range, 0.80-2.53] vs. median, 0.01 [interquartile range, 0.01-0.01], p < 0.001, respectively). The median strain ratio of the control group was 0.01 (interquartile range, 0.01-0.01), and there was no significant difference compared to normal areas of the study group. There was, however, a significant difference between the control group cartilage and pathologic cartilage of the study group (p < 0.001). CONCLUSIONS: Elastosonography may be an effective, easily accessible, and relatively simple tool to demonstrate pathologic cartilage and to differentiate it from normal cartilage in the absence of advanced imaging facility such as MRI. KEY POINTS: • Elastosonography uses colour-maps and strain ratios for evaluating tissue deformability. • Colour change from blue to red and increased strain ratio represent softening. • Normal cartilage shows decreased compressibility, represented by blue colour and low strain ratio. • Pathologic cartilage shows increased compressibility, represented by red colour and high strain ratio. • Elastosonography may be used for differentiating pathologic cartilage from normal cartilage.

Transabdominal Sonographic Study of the Cavum Vergae Detection Rate in Healthy Third-Trimester Fetuses.

OBJECTIVES: We aimed to measure the thickness and volume of the cavum vergae by sonography in fetuses at gestational ages of 25 to 41 weeks to determine the relationship of cavum vergae thickness and volume with gestational age and biparietal diameter and to estimate the rate of cavum vergae closure in relation to gestational age. METHODS: A total of 336 patients in their third trimester of pregnancy had transabdominal sonography. The fetal cavum vergae was scanned in the coronal and axial planes. The thickness of the anteroposterior diameter of the cavum vergae and the largest inner surface were measured after marking the internal borders of the structure, and then longitudinal and vertical sizes were obtained. The values obtained were multiplied by each other and then by 0.52 to obtain the cavum vergae volume. RESULTS: In 55 of 322 cases, the cavum vergae volume and thickness could not be calculated because the cavum vergae was closed. In the remaining cases, the cavum vergae volume and thickness and biparietal diameter were measured. Although the degree of correlation between cavum vergae thickness and volume increased with increasing gestational age, there was no correlation between cavum vergae thickness and volume at 37 to 41 weeks. There was a positive but weak statistically significant correlation between biparietal diameter and cavum vergae volume (P= .05), but there was no statistically significant correlation between biparietal diameter and cavum vergae thickness. The cavum vergae closure rate increased significantly as gestational age increased (P < .001). CONCLUSIONS: Cavum vergae closure increases as gestational age increases. However, we did not find any relationships between cavum vergae thickness and volume, gestational age, and biparietal diameter.

Choroid plexus separation in fetuses without ventriculomegaly: Natural course and postnatal outcome.

PURPOSE: To evaluate fetuses with choroid plexus separation without ventriculomegaly in terms of fetal malformations, behavior of the separation during follow-up, and postnatal outcome. METHODS: In total, 172 fetuses with choroid plexus separation without ventriculomegaly were included in this prospective study. Fetal sonography was performed at 2- to 4-week intervals, and detailed physical and neurologic examinations were performed after their delivery. Fetuses were categorized into normal and abnormal subgroups according to the outcome. RESULTS: Sixteen fetuses (9.3%) were included in the abnormal-outcome group and 156 fetuses (90.7%) were included in the normal-outcome group. Both the initial mean lateral ventricular diameter (9.3 mm versus 8.6 mm) and the initial mean choroid plexus separation (4.8 mm versus 3.3 mm) were greater in the abnormal group than in the normal group (p < 0.001 for both comparisons). We found that 4.0 mm was the best cutoff point of choroid plexus separation to detect a major anomaly, with 87.5% sensitivity and 93.6% specificity. CONCLUSIONS: Choroid plexus separation without ventriculomegaly often resolves within the third trimester and does not affect postnatal outcome. It can be associated with various fetal malformations; however, with a comprehensive examination, all fetal malformations can be detected prenatally. Follow-up sonography studies would be useful, especially in the case of suspected corpus callosum agenesis.

The potential effect of anatomic relationship between the femur and the tibia on medial meniscus tears.

BACKGROUND: The anatomic and the kinematical relationships between the femur and the tibia have been previously examined in both normal and diseased knees. However, less attention has been directed to the effect of these relationships on the meniscal diseases. Therefore, we aimed to investigate the impact of femorotibial incongruence on both lateral and medial meniscal tears. MATERIALS AND METHODS: A total of 100 images obtained from MRI of 100 patients (39 males and 61 females) were included in the study. Diameters of the medial and the lateral femoral condyles, thicknesses of the menisci, and diameters of the medial and the lateral tibial articular surfaces were measured. RESULTS: The medial meniscus tear was detected in 40 (40 %) patients. However, no lateral meniscus tear was found. Significant relationships were found between the diameters of the posterior medial femoral condyle and the medial tibial superior articular surface and between the diameters of the posterior lateral femoral condyle and the lateral tibial superior articular surface. The mean values for the diameter of the medial condyle of the femur, the lateral condyle of the femur, the medial superior articular surface of the tibia, and the lateral superior articular surface of the tibia were found to be significantly higher in cases with meniscus tear compared to cases without meniscus tear. However, no significant difference was present regarding the thicknesses of the medial and the lateral menisci. A positive relationship between the diameter of the posterior medial femoral condyle and the tibial medial superior articular surface was found in cases with (n = 40) (r (2) = 0.208, p = 0.003) and without tear (n = 60) (r (2) = 0.182, p = 0.001). In addition, a significant positive relationship was found between the diameter of the posterior medial femoral condyle and the medial tibial superior articular surface in cases with and without tear. CONCLUSION: The impact of femorotibial incongruence on the medial meniscus tear is important for the understanding of the lesions.

Impact of fibular torsion and rotation on chronic ankle instability.

BACKGROUND: The fibula is known not to involve in transmission of weight but known simply as an ankle stabilizer. However, its main function in stabilizing the ankle remains obscure. Since the fibula has an impact on torsion and rotation of the ankle, its effect on lateral ankle instability should be investigated. MATERIALS AND METHODS: Twenty patients with lateral ankle instability (Group 1) and 19 healthy volunteers (Group 2) were included in the study. The tibiofibular and talofibular relationships were evaluated using MRI images. Fibular torsion and rotation angles were calculated using a new method. Range of motion of the ankle joint was investigated while the knee was at flexion (90°) and extension (0°). The comparisons performed between the 2 groups and independent from the groups were statistically evaluated and, the p value of <0.05 was considered as statistically significant. RESULTS: A significant difference was found between the two groups for age (p<0.05). There were no statistically significant differences between the right and left sides for all measurements in the group 1 and 2 (p>0.05). There was a statistically significant difference between the two groups in dorsal flexion when the knee is at flexion (90°) and extension (0°) position. There was also a statistically significant difference between the two groups in plantar flexion which was measured while the knee was at extension (0°) position. No statistically significant difference was found between both groups in terms of fibular torsion and rotation. However, independent from the groups when the patients were divided into 2 groups according to whether the fibula localized posteriorly or not, in patients with posteriorly localized fibula it was demonstrated that the fibular torsion and rotation was increased significantly. CONCLUSION: We did not detect any relationship between fibular torsion and rotation and ankle instability. However, independent from the groups when the patients were divided into 2 groups according to whether the fibula localized posteriorly or not, we realized that in patients with posteriorly localized fibula, fibular torsion and rotation significantly increased. This finding did not explain the cause of instability. However, it may gain significance with new further studies regarding ankle instability.

Effect of sarcopenia on mortality in acute stroke patients receiving endovascular treatment.

BACKGROUND: To investigate the effect of sarcopenia on mortality in patients with acute ischemic stroke caused by anterior circulation large artery occlusion who underwent endovascular treatment. METHODS: Acute ischemic stroke patients (n = 194) treated with mechanical thrombectomy who underwent chest computed tomography between 2019 and 2022 (median age, 69 [interquartile range: 61-77], 95 females, 99 males) were evaluated retrospectively. The cross-sectional area and density of the pectoralis muscle [pectoralis muscle area (PMA) and pectoralis muscle density (PMD)] at the level of the aortic arch and the erector spinae muscle at the T12 level [erector spinae muscle area (ESMA) and erector spinae muscle density (ESMD)] were measured. The association between skeletal muscle parameters and mortality outcomes was investigated using the receiver operating characteristic (ROC) curve and multivariable logistic regression analyses. RESULTS: The 90-day mortality rate was 32% in the study population (n = 62). The ROC analysis revealed that ESMD [area under the curve (AUC): 0.765] and PMD (AUC: 0.759) performed best in the prediction of 90-day mortality. In the multivariable logistic regression analysis, PMD [odds ratio (OR): 0.896; 95% confidence interval (CI): 0.846-0.948; p < 0.001], ESMA (OR: 0.929; 95% CI: 0.878-0.983; p = 0.011), and ESMD (OR: 0.947; 95% CI: 0.913-0.983; p = 0.004), but not PMA, were independent risk factors for 90-day mortality. CONCLUSION: PMD, ESMA, and ESMD may be risk factors for 90-day mortality after mechanical thrombectomy for acute ischemic stroke.

Cam impingement of the posterior femoral condyle in unicompartmental knee arthroplasty.

PURPOSE: There has been much emphasis on the importance of cam impingement, which is a cause of pain and knee hyperflexion restriction in unicompartmental knee arthroplasty (UKA). This study aimed to correlate cam impingement in the posterior femoral condyle with an α-angle showing the severity of the impingement. METHODS: The study groups consisted of 87 knees of 74 patients operated on with phase 3 medial Oxford UKA. Postoperatively, Group A (68 knees, 78.2 %) had no remnant of cam lesion; Group B (19 knees, 21.8 %) had cam lesion remnants. In Group C (18 knees, 20.7 %), which is a subgroup of Group A, cam lesions seen preoperatively were cleaned and not seen postoperatively. RESULTS: The mean increase in active flexion was 20.4° (± 7.3°) in Group A, 9.7° (± 6.1°) in Group B and 20.8° (± 7.3°) in Group C. The difference between Group A and Group B and between Group B and Group C was statistically significant (p < 0.001, p < 0.001). The mean decrease of α-angle was 11.2° (± 4.1°) in Group B, and 31.1° (± 3.4°) in Group C. The difference was statistically significant (p < 0.001). Mean Oxford Knee Scores were 24 preoperatively, 41 postoperatively in Group A; 22 preoperatively, 38 postoperatively in Group B; and 24 preoperatively, 40 postoperatively in Group C. The differences were not significant. CONCLUSIONS: Posterior condylar cam lesion is an impingement which limits hyperflexion and may be an early clinical finding prior to bearing dislocation and wear. The α-angle is a marker showing the severity of this cam lesion. This problem can be overcome using intraoperative fluoroscan views during cam excison and replacing the femoral component in 105° knee flexion.

Use of contact pressure-sensitive surfaces as an indicator of graft tension in medial patellofemoral ligament reconstruction.

BACKGROUND: No previous description has been made about an objective method to test the graft resistance in MPFL reconstruction intraoperatively. In our study, we aimed to obtain intraoperative objective data about the graft resistance using contact pressure-sensitive surfaces and measuring pressure formed under the graft. MATERIALS AND METHODS: In 2012, double-layered contact pressure-sensitive Fuji Prescale Film bands were placed under MPFL in 15 fresh-frozen high above-knee amputates (Group 1) and under graft in 10 patients who underwent MPFL reconstruction (Group 2). Measured values at different flexion angles were compared between and in groups. RESULTS: Statistical analysis was performed by Student's t test. It has been found that the pressure under the graft was higher in patients having reconstruction as compared to the pressure under natural MPFL. Decreasing pressure values were observed with increasing flexion angles in both groups. CONCLUSION: Contact pressure-sensitive surfaces provided objective data when placed under the graft in natural MPFL and during surgery. Therefore, they may be used as an objective marker providing information about graft resistance.

Low local curvature index and history of previous surgery are risk factors for revision in focal metallic inlay implants.

BACKGROUND: Focal chondral defects are debilitating lesions with poor healing potential. Focal metallic inlay implants were developed as a salvage procedure, whose reoperation causes and risk factors for revision are still debatable. The aim of this study is to analyze the local subchondral curvature matching of focal metallic inlay implants and its effects on survival and clinical results. METHODS: Patients operated with a knee focal metallic inlay resurfacing implant between 2014 and 2017 were eligible. Surgery was indicated for painful, focal, full-thickness cartilage lesions that had failed alternative treatments. Inclusion criteria were patients treated for a lesion ≤ 5 cm2 in the femoral condyle, aged 40-65 years, with complete surgical records and a knee CT scan. The curvature index (Kindex) was calculated as the ratio of the mean curvature of the implant (K1) to the mean curvature of the subchondral bone (K2). RESULTS: Sixty-nine patients were included, of which 60.9% were female. Mean age was 54.8 ± 6.0. Seven patients (10.1%) underwent revision surgery. When adjusted for age and sex, lesion size was not significantly correlated to revision in a multivariate regression model, while previous surgery and smaller K index were. A positive history for previous surgery was significantly correlated with worse clinical outcomes in surviving patients. CONCLUSION: A positive history of previous knee surgery and a low local curvature index are risk factors for revision after focal metallic inlay implant resurfacing. Patients with a history of knee surgery should be counseled on the advantages and disadvantages before undergoing a focal resurfacing procedure.

The Co-Use of Stromal Vascular Fraction and Bone Marrow Concentrate for Tendon Healing.

OBJECTIVE: The Achilles tendon is the most frequently injured tendon in the human body, despite being the strongest. Many conventional treatments including medication, surgical interventions, and physical therapy are available, however, the desired results are often not achieved. Stromal vascular fraction (SVF) and bone marrow concentrate (BMC) are two additional cellular treatment options. The purpose of this study is to evaluate the effect of SVF and BMC, used as a combination, for the treatment of Achilles tendon injuries. METHODS: Five male New Zealand rabbits were used for each of the 6 study groups. A 3-mm of SVF and BMC were injected on the Achilles tendons at certain ratios. The histological results were classified by the Movin grading system for tendon healing. The collagen type-I and type-III structures in the tendons were examined by immunohistochemical evaluation. The expressions of tendon-specific genes were also examined by using the RT-PCR method to analyze tendon healing. RESULTS: Histological and immunohistochemical evaluation indicated that tendons receiving the SVF and BMAC mixture performed better than control and individual groups (p < 0.05). Moreover, RT-PCR evaluation showed that mixture-receiving groups were the closest similar to the uninjured group (p < 0.05). CONCLUSION: The combined use of BMC and SVF improved Achilles tendon healing when compared to the individual use of each mixture.