Femoral Trochlea Research Articles

Evaluation of proximodistal patellar alignment in small breed dogs with or without patellar luxation using the Insall-Salvati, Caton-Deschamps, and Blackburne-Peel indices.

Patellar luxation in dogs is thought to be related to proximally (patella alta) or distally (patella baja) positioned patella in the femoral trochlea. The aim of the present study was to calculate and compare the values of Insall-Salvati (ISI), Caton-Deschamps (CDI), and Blackburne-Peel indices (BPI) in orthopedically healthy dogs and dogs with various grades of medial patellar luxation (MPL) from small breeds on mediolateral radiographs. The study included 87 dogs (138 stifles) from four breeds (Mini-Pinschers, Pomeranians, Chihuahuas, and Yorkshire terriers). Seventy joints (53 dogs) were diagnosed with various grades of MPL and another 68 joints from 34 dogs, free of orthopedic or neurological disorders, were used as controls. Receiver operating characteristic (ROC) analysis was performed to evaluate the diagnostic value of the three indices. The CDI and BPI showed no significant difference between healthy and MPL joints. The ROC analysis showed that all three studied indices of proximodistal patellar position had poor diagnostic values with low sensitivity and specificity of respective cutoff values. In dogs from the studied four small breeds, the proximodistal ISI, CDI, and BPI patellar indices could not discriminate reliably between healthy stifle joints and joints with MPL.

A study on the correlation between patellofemoral joint morphology and early patella malacia in young adults: quantitative analysis based on magnetic resonance.

The aim of this study was to quantitatively measure the morphology of the patellofemoral joint by magnetic resonance imaging (MRI) in young adults, to investigate the relationship between the morphology of the patellofemoral joint and chondromalacia patellae (CP), and to provide an imaging reference for early clinical diagnosis of CP. A total of 57 cases of CP and 138 cases of normal knees were retrospectively collected and assigned to the CP group and control group, respectively. The morphological parameters of the patellofemoral joint were measured systematically. The statistical software SPSS 22.0 was used in correlation analysis. Logistic regression was used for univariate analysis. A P value <0.05 was defined as statistically significant. Wiberg index, patellar depth, and the lateral angle of the patella in the CP group were significantly lower than those in the control group (P=0.043, 0.001, 0.040, respectively). The width of the medial side of the trochlea, the ratio of the internal and external articular surfaces of the trochlea, the depth of the trochlea, and the inclination angle of the lateral trochlea in the CP group were significantly lower than those in the control group (P=0.003, 0.020, 0.000, 0.040, respectively), whereas the angle of the trochlea in the CP group was significantly higher than that in the control group (P=0.010). The lateral patellofemoral angle (LPA) and lateral patellofemoral contact width in the CP group were significantly lower than those in the control group (P=0.010, 0.010, respectively). In the CP group, with gender as a covariate, there were significant statistical differences between male and female in patellar depth, lateral patellar inclination angle, lateral trochlear inclination (LTI) angle, and lateral patellar contact surface width (P<0.05), whereas in the control group, there were significant differences in Wiberg index, patellar depth, medial trochlear width, and lateral patellofemoral contact surface width between male and female gender (P<0.05). The prevalence of CP in women was significantly higher than that in men and the reduction of trochlea width and the patella depth is an important factor for the incidence of female CP. Morphological characteristics of the patellofemoral joint are significantly correlated with the occurrence of CP in young adults.

Comparing the findings of clinical examination versus magnetic resonance imaging for the diagnosis of ligamentous injuries of knee in rural area

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; The knee is a complex synovial joint allowing flexion, extension, anteroposterior gliding and internal-external rotation. The major articular surfaces are the medial and lateral condyles of the femur and patellar surface. The aim of the study was to compare the findings of clinical examination versus magnetic resonance imaging (MRI) for the diagnosis of ligamentous injuries of knee in rural area.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; Present study was an observational study carried out at rural medical college under orthopaedic department. All patients coming with ligamentous injury to orthopaedic department were studied. Thus such 50 cases were studied. All cases were referred to radiology department for MRI of knee. MRI reports and clinical reports were compared and analysis was done. Cases contraindicated for MRI examination were excluded from study. General demoghraphic history, clinical presentation and MRI reports were recorded. All data was compiled in Microsoft excel and analysed using OpenEPi 2.3.1.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; Mean age was 46.4±11.2 years. Majority were males 70% and 30% were females. Swelling 62% was most commonly seen followed by knee pain. Majority 58% cases had grade 3 tear on MRI, followed by 36% had grade II and only 6% had grade I. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; MRI is an excellent, non-invasive, radiation free imaging modality with multilane capabilities and excellent soft tissue delineation. It can accurately detect, localize and characterize various internal derangements of the knee joint and help in arriving at a correct anatomical diagnosis thereby guiding further management of the patient.&lt;/p&gt;

Intercondylar notch volume in patients with posterior cruciate ligament tears and tibial avulsion injuries: a study applying computed tomography

BackgroundTwo relatively common forms of injury exist in the posterior cruciate ligament (PCL) after the onset of trauma: PCL tear and tibial avulsion fracture. The mechanism for the occurrence of these different forms of injury is not known. Herein, we aimed to investigate this mechanism by comparing the intercondylar notch parameters between patients with PCL tears and those with PCL avulsion fractures of the tibial insertion.MethodsFifty-three patients with PCL tears (37 male, 16 female: median age of 37 years: range 18–54 years) and 46 patients with avulsion fractures of tibial insertion (33 male, 13 female: median age of 33 years: range 18–55 years) were included in this study. Three-dimensional computed tomography (CT) was applied to measure the intercondylar notch width index and intercondylar notch volume. The intercondylar notch volume was simulated as the truncated-pyramid shape. Measurements of the top and bottom areas of this model were conducted on the slice containing the most proximal (S1) and most distal (S2) levels of Blumensaat’s line. Femoral condyle height (h) was defined as the vertical distance between two parallel planes, and the volume was calculated as h(S1 + S2 + √(S1S2))/3. The values of S1, S2, h, notch volume, the body mass index (BMI), intercondylar notch width (NW), femoral condylar width (FW) and notch width index (NWI) were compared among the PCL tear and avulsion-fracture groups.ResultsThe results show a significant difference in the S2 and normalized intercondylar notch volumes among patients with PCL tears and tibial avulsion injuries. Patients with PCL tears have smaller S2 and intercondylar notch volumes than those with tibial avulsion. There were no significant differences between the two groups in S1 or the 2D notch measurement parameters, such as the NW, FW and NWI. In addition, logistic regression analysis revealed notch volume and body mass index (BMI) as two significant independent predictors for PCL tears.ConclusionDecreased intercondylar notch volume and increased BMI are associated with an increased incidence of PCL tears. The occurrence of PCL tears and tibial avulsion injuries is influenced by the femoral intercondylar notch volume, and the measurement of the notch volume could be useful for identifying patients at risk for PCL tears.

Assessment of influences of posterior rotation of the tibial condyles on the Insall-Salvati ratio

The positional relationship between patellar and femoral articular surfaces may vary according to the degree of posterior rotation of the tibial condyle, which may influence the patellar configuration. We hypothesized that the configuration of the patella has a rhomboid transformation similar to that of the tibial condyle. This cohort study included 313 patients with knee pain who underwent lateral-view knee digital radiography. The length of the long axis, short axis of the patella, and patellar tendon length of the patellofemoral joint were measured. The patella axis ratio (length of long/short axis) as patellar configuration and Insall-Salvati ratio were calculated. Correlations between the configuration of the tibial condyle and the three length parameters and the Insall-Salvati ratio were assessed. Posterior rotation and the rhomboid transformation of the tibial condyle were positively correlated with the length of the long axis of the patella and negatively correlated with the Insall-Salvati ratio. The more the tibial articular surface shifted posteriorly due to posterior rotation and rhomboid transformation of the tibial condyle, the longer the long axis of the patella was, and the smaller the Insall-Salvati ratio was. The long axis of the patella became longer due to rhomboid transformation, similar to the tibial condyle.

Patellar Tendon–Trochlear Groove Angle Measured on a Single Computed Tomography Slice of the Distal Femoral Trochlear Groove Is a Reliable Measurement for the Evaluation of Patellar Instability

To verify the reliability of patellar tendon-trochlear groove angle (PTTG-A) measured by computed tomography (CT) and the clinical significance in evaluation of patellar instability. A retrospective study of hospitalized patients with knee pain or injury and had knee CT from January 2017 to June 2021 was performed. PTTG-A and tibial tuberosity-trochlear groove (TT-TG) distance were measured on CT. Spearman correlation analysis was analyzed between the 2 measurements. The intraclass correlation coefficient was determined for inter- and intraobserver reproducibility. The capacity of PTTG-A and TT-TG to predict patellar instability was evaluated by the receiver operating characteristic curve. Data from the control group were used to determine the pathologic thresholds and logistic regression analysis. Included were 113 patients. There were 60 patients with the history of at least 2 episodes of patellar dislocation (study group) and 53 patients without a history of patellar dislocation (control group). The respective PTTG-A and TT-TG distances in the study group (35.2 ± 8.4° and 19.6 ± 4.6 mm) were significantly greater than those of the controls (20.8 ± 5.8° and 13.3 ± 4.5 mm) (P < .001). The correlation between the 2 measurements was strong (r= 0.730, P < .001). The inter- and intraobserver reliability of the PTTG-A were better than TT-TG distance in both groups. The AUC of PTTG-A was greater than that of the TT-TG distance (0.895 vs 0.769, respectively). With the cutoff value of PTTG-A and TT-TG being 26.3° and 16.3 mm, the value of the pathologic threshold of PTTG-A was 30.0°, with a dominance ratio of 16.88 (95% confidence interval 2.88-98.89, P= .002). The PTTG-A measured on a single CT slice of the distal femoral trochlear groove is a more reliable measurement than TT-TG distance for the prediction of patellar instability. III; A retrospective cohort study.

Reconstruction of the medial patellofemoral ligament with nonresorbable suture tape normalizes patellar maltracking independent of patella-side fixation technique.

Patellar maltracking caused by a rupture of the medial patellofemoral ligament (MPFL) can be improved by MPFL reconstruction (MPFL-R) with a tendon graft. Nonresorbable suture tape (FiberTape®, FT) is possibly becoming an option to tendon grafts for MPFL-R. Patella-side fixation of FT can be performed with suture anchors or via soft-tissue fixation. The aim of this study was to investigate patellar tracking considering soft-tissue-based and anchor-based patella-side fixation techniques. In eight fresh-frozen human knee joint specimens (m/f 4/4; age 75 ± 10years), the MPFL was identified, and a rupture was placed near the femoral insertion site. In the study group (SG; 4 knees), soft-tissue fixation of the FT was performed at the medial patellar retinaculum; in the control group (CG; 4 knees), FT was fixed at the patella via suture anchors. For native MPFL (nMPFL), ruptured ("injured") MPFL (iMPFL) and reconstructed MPFL (FT-MPFL-SG, respectively, FT-MPFL-CG) cone beam CT scans were performed in 15°, 30°, and 45° of knee joint flexion. Patellar tracking was assessed using the radiological parameters patellar tilt (PT), congruence angle (CA) and posterior patellar edge-trochlear groove ratio (PTR). All recorded radiological parameters increased, respectively, decreased in the CG and SG from the nMPFL to the iMPFL state. After MPFL-R, all parameters normalized when compared to the intact state (nMPFL), regardless of patella-side fixation technique. All investigated parameters of patellotrochlear alignment were positively, respectively, negatively significantly (p < 0.05) correlated throughout all evaluated conditions (nMPFL, iMPFL, FT-MPFL-SG, FT-MPFL-CG). MPFL-R with a nonresorbable suture tape can normalize patellar maltracking in fresh-frozen human knee joint specimens in earlier degrees of knee joint flexion independent of patella-side fixation technique. The investigated parameters of patellotrochlear alignment correlate with each other.

Anteromedialization Tibial Tubercle Osteotomy Improves Patellar Contact Forces: A Cadaveric Model of Patellofemoral Dysplasia

Background: Patellofemoral (PF) dysplasia is common in patients with recurrent patellar instability. Tibial tubercle osteotomy (TTO) is performed with goals of correcting patellar maltracking and redistributing contact forces across the PF joint. The biomechanical effects of TTO in the setting of PF dysplasia have not been quantified. Purpose/Hypothesis: To quantify patellar contact mechanics and kinematics after TTO in the setting of PF dysplasia. We hypothesized that a simulated anteromedialization (AMZ) TTO would improve PF contact mechanics as compared with a pure medialization TTO. Study Design: Controlled laboratory study. Methods: PF dysplasia with Dejour type D classification was simulated in 7 cadaveric knees by replacing the native patellar and trochlear surfaces with synthetic polymeric patellar and trochlear implants. On each specimen, a flat TTO was fixed in 3 distinct positions simulating a pathologic lateralized tubercle (pathologic condition), a medialized tubercle (Elmslie Trillat), and an AMZ tubercle. The sum of forces acting on the medial and lateral patellar facet and patellar kinematics was computed for each knee for each condition from 0° to 70° of flexion at 10° increments. Results: Relative to the pathologic condition, AMZ TTO decreased contact forces across the lateral facet (20°-50° and 70° of flexion). Relative to the pathologic condition, Elmslie Trillat TTO had no effect on contact forces on either compartment. Relative to the Elmslie Trillat TTO, the AMZ TTO had significantly decreased contact forces across the medial facet (at 40°, 60°, and 70° of flexion). No significant differences in joint kinematics occurred across any groups. Conclusion: Of all groups studied, AMZ TTO resulted in significantly decreased patellar contact forces in simulated dysplastic PF joints. AMZ may be considered in certain patients with PF dysplasia to avoid medial compartment PF chondral overload. Clinical Relevance: PF dysplasia is common in patients with recurrent patellar instability who warrant surgical intervention to prevent subsequent recurrence. Numerous interventions to treat this condition, including various TTOs, have been proposed without a clear consensus. This cadaveric biomechanical study demonstrates that AMZ TTO resulted in more favorable PF contact mechanics than Elmslie Trillat TTO in a model representing PF dysplasia. AMZ TTO may be considered for patients in the setting of recurrent instability with PF dysplasia to avoid cartilage overload on the medial compartment of the PF joint.

Axial orientation of the femoral trochlea is superior to femoral anteversion for predicting patellar instability.

The femoral anteversion angle is considered to be the same as femoral torsion; however, the femoral anteversion angle is strongly influenced by the femoral posterior condylar morphology. It remains unclear whether the femoral anteversion angle and axial orientation of the femoral trochlea can predict patellar instability. This study aimed to redefine the femoral inherent torsion, verify whether the femoral anteversion angle reflects the femoral inherent torsion, and compare the validity and calculate the cut-off values of the femoral anteversion angle and femoral trochlear axial orientation for predicting patellar instability. Seventy-three patients with patellar instability and 73 matched controls underwent computed tomography to measure the femoral anteversion angle, femoral inherent torsion, and femoral trochlear axial orientation. Pearson's product moment correlation coefficients and linear regression were calculated to determine correlations between measurements. Receiver operating characteristic curves and nomograms were plotted to evaluate the predictive validity of the femoral anteversion angle and femoral trochlear axial orientation for patellar instability. All measurements showed excellent intra- and inter-observer reliability. Compared with the control group, the patellar instability group had a significantly larger femoral anteversion angle (25.4 ± 6.4° vs. 20.2 ± 4.5°) and femoral inherent torsion (18.3 ± 6.7° vs. 15.8 ± 3.4°), and significantly smaller femoral trochlear axial orientation (58.1 ± 7.3° vs. 66.9 ± 5.1°). The femoral anteversion angle and femoral trochlear axial orientation had area under the receiver operating characteristic curve values of 79 and 84%, respectively, and cut-off values of 24.5° and 62.7°, respectively. The calibration curve and decision curve analysis showed that the femoral trochlear axial orientation performed better than the femoral anteversion angle in predicting patellar instability. There was a strong correlation between the femoral anteversion angle and femoral inherent torsion (r > 0.8). Linear regression analysis of the femoral inherent torsion with the femoral anteversion angle as the prediction variate showed moderate goodness-of-fit (adjusted R2 = 0.69). The femoral anteversion angle moderately reflects the femoral inherent torsion. The femoral trochlear axial orientation is better than the femoral anteversion in predicting patellar instability in terms of predictive efficiency, consistency with reality, and net clinical benefit. These findings warn orthopaedists against overstating the role of the femoral anteversion angle in patellar instability, and suggest that the femoral trochlear axial orientation could aid in identifying at-risk patients and developing surgical strategies for patellar instability. III.

Morphometric characteristics of the knee are associated with the injury of the meniscus

BackgroundTo assess the geometrical risk factors for meniscal injuries. We hypothesized that the narrowness of the intercondylar notch and the smaller tibial spine could increase the risk of meniscal injuries.MethodsWe retrospectively studied two hundred and seven patients examined for knee magnetic resonance images. Two experienced orthopedists evaluated the severity of meniscal injuries. The notch width, bicondylar notch width, notch width index, condyle width of the femur, tibial spine height, and intercondylar angle were measured in magnetic resonance image slides by two blinded orthopedists.ResultsA total of 112 patients with a meniscus injury and 95 patients were as healthy control in all two hundred and seven patients. The NWI (P = 0.027) in patients with meniscus injuries was significantly different from the control group. A 1 SD (0.04 mm) increase in NWI was associated with a 0.4-fold increase in the risk of meniscal injury. A 1 SD (0.04 mm) increase in NWI was associated with a 0.64-fold increase in the risk of grade 3 meniscal injury. Furthermore, NWI and medial spine height are decreased significantly in grade 2 (P < 0.05) meniscal injury than in other grades. The medial spine height was significantly decreased in the meniscal injury group (P = 0.025), and the decrease in medial spine height would increase the risk of meniscal injury (OR = 0.77) and grade 3 meniscal injury (OR = 0.8).ConclusionsThe stenosis of the femoral intercondylar notch and small medial tibial spine is risk factors of meniscal injury. The decreased NWI and the medial tibial spine height were also associated with the severity of the meniscal injury.

Early patellofemoral cartilage and bone pathology in a rat model of noninvasive anterior cruciate ligament rupture

ABSTRACT Objective Anterior cruciate ligament rupture (ACLR) is a risk factor for the development of post-traumatic osteoarthritis (PTOA). While PTOA in the tibiofemoral joint compartment is well-characterized, very little is known about pathology in the patellofemoral compartment after ACL injury. Here, we evaluated the extent to which ACLR induces early patellofemoral joint damage in a rat model. Methods Adult female Lewis rats were randomized to noninvasive ACLR or Sham. Two weeks post-injury, contrast-enhanced micro-computed tomography (µCT) of femoral and patellar cartilage was performed using 20% v/v ioxaglate. Morphometric parameters of femoral trochlear and patellar cartilage, subchondral bone, and trabecular bone were derived from µCT. Sagittal Safranin-O/Fast-Green-stained histologic sections were graded using the OARSI score in a blinded fashion. Results Cartilage and bone remodelling consistent with an early PTOA phenotype were observed in both femoral trochleas and patellae. ACLR caused osteophyte formation of the patella and pathology in the superficial zone of articular cartilage, including surface fibrillation, fissures, increased cellularity, and abnormal chondrocyte clustering. There were significant increases in thickness of patellar and trochlear cartilage. Loss of subchondral bone thickness, bone volume fraction, and tissue mineral density, as well as changes to patellar and trochlear trabecular microarchitecture, were indicative of catabolic bone remodelling. Several injury-induced changes, including increased cartilage thickness and trabecular spacing and decreased trabecular number were more severe in the patella compared to the trochlea. Conclusion The patellofemoral joint develops mild but evident pathology in the early period following ACL rupture, extending the utility of this model to the study of patellofemoral PTOA.

Lateral Femoral Trochlea Osteochondral Flap Reconstruction of Proximal Pole Scaphoid Nonunions

The medial femoral trochlea flap has been described as a method of scaphoid proximal pole nonunion reconstruction when the proximal pole is deemed nonsalvageable. The lateral femoral trochlea (LFT) is an alternative donor site providing a comparable vascularized convex osteochondral flap. We describe the technique and outcomes of our first 17 cases of LFT flap reconstruction of the proximal scaphoid pole with a minimum follow-up of 14 months. Seventeen of the first 24 patients who underwent LFT scaphoid reconstruction at 3 institutions were able to be contacted for clinical follow-up and chart reviews. We recorded patient ageand sex, duration of nonunion, number of previous surgical procedures, details of surgical technique, achievement of osseous union, complications, additional postoperative procedures, preoperative and postoperative pain, and range of motion. Preoperative and postoperative scapholunate and radiolunate angles were analyzed on x-rays and achievement of osseous union on computerized tomography scans. The average age of patients included was 35 years (range, 16-55 years). Follow-up data were recorded at an average of 33 months (range, 14-62 months). Ten patients had previous procedures (average, 1; range, 0-2). Median duration from trauma to LFT was 3.4 years (range, 8 months-12 years) among patients who had a recognized date of injury. Osseous healing was achieved in 16 of 17 patients and confirmed by computerized tomograpy scan. Twelve patients reported complete pain relief, while 5 reported partial pain relief. Final postoperative range of motion was 59°extension (range, 30°-85°) and 50° flexion (range, 10°-80°), which was comparable to preoperative values. Preoperative (59°) and postoperative (55°) scapholunate angles were similar to normal wrists. Vascularized LFT flaps provide an alternative donor site for vascularized osteochondral reconstruction of proximal pole scaphoid nonunion. Rate of union, range of motion, and pain relief are similar to reported results with medial femoral trochlea flap reconstruction. Therapeutic IV.

Successful Fixation of Traumatic Articular Cartilage-Only Fragments in the Juvenile and Adolescent Knee: A Case Series.

Some surgeons are now considering fixation of traumatic chondral-only fragments in juvenile knees, but few data remain to guide treatment. To determine if surgical fixation of chondral-only fragments in the juvenile knee results in an adequate healing response with successful imaging and clinical outcomes. Case series; Level of evidence, 4. Data were collected on 16 skeletally immature patients treated with fixation of chondral-only fragments with a minimum 1-year follow-up. Patients were selected by the operating surgeons based on the quality and size of the chondral fragment. Demographic data, lesion characteristics, surgical procedure details, complications, and postoperative imaging were assessed. Validated outcome measures were collected pre- and postoperatively and included the following scores: International Knee Documentation Committee (IKDC), Marx Activity Scale, Knee injury and Osteoarthritis Outcome Score (KOOS), Hospital for Special Surgery Pediatric Functional Activity-Brief Scale (HSS Pedi-FABS), Patient-Reported Outcomes Measurement Information System (PROMIS)-Physical Health and PROMIS-Psychological Health, and Tegner. The mean age of our patient cohort was 14.9 years. The mean size of the repaired defects measured 3.2 cm2. Injury sites included the patella (n = 1), medial femoral condyle (n = 3), trochlea (n = 4), and lateral femoral condyle (n = 8). Within the mean follow-up time of 42.3 months (range, 15-145), there was 1 clinical failure with loosening of the chondral fragment and the need for reoperation. At a mean follow-up of 3.5 years, the mean (interquartile range) patient-reported outcome scores were as follows: IKDC, 95.2 (94.3-100); Marx Activity Scale, 11.5 (11.5-16); KOOS, 95.81 (93.5-95.81); HSS Pedi-FABS, 16.94 (11.5-26); PROMIS-Physical Health, 93.75% (90%-100%); PROMIS-Psychological Health, 90% (88.75%-100%); and Tegner, 5.69 (4.75-7). All patients who were engaged in sports before injury returned to the same or higher level of competition with the exception of 1 patient. Primary repair of chondral-only injuries with internal fixation can be a successful treatment option in selected patients. Clinical and imaging results at final follow-up suggest that reintegration of the cartilage fragment is achievable and leads to excellent clinical function and a high return-to-sports rate.

Effect of patellar resurfacing surgery on bleeding in total knee arthroplasty.

Postoperative bleeding is one of the most important factors affecting clinical and functional results in total knee arthroplasty. Therefore, many studies have been conducted on bleeding in arthroplasty patients. However, there are very few reports investigating the effect of patellar surface replacement on bleeding in knee arthroplasty. We, therefore, aimed to investigate the effect of patellar surface replacement on postoperative bleeding. In this retrospective study, 30 with patellar resurfacing were compared with 39 without patellar resurfacing among patients who had undergone total knee replacement due to primary osteoarthritis. Demographic data, amount of transfusion, preoperative and postoperative hemoglobin and hematocrit values, and total, visible, and hidden blood loss values were recorded. No statistical difference was found between the two groups in terms of demographic values. There was no significant difference between the groups in terms of the amount of blood in the drain, total blood loss, hidden blood loss, and blood transfusion in patients who had and had not undergone patellar resurfacing. A positive significant correlation was found between postoperative drainage volume and total blood loss. Patellar component application in patients who had undergone total knee arthroplasty does not change the blood loss of the patients.

Patella-Posterior Turning Point of the Distal Femur Distance Is a Potential Indicator for Diagnosing Patella Alta in Recurrent Patellar Dislocation Population

To introduce a simple patellar height measurement method (patella-posterior turning point of the distal femur [P-PTP] Distance) independent of patellar anatomy with standardized patient position, and tested the reliability, validity, and diagnostic accuracy compared with commonly used ratios in knee extension. We retrospectively reviewed 418 computed tomography (CT) images of the knee joint in a group of patients who were diagnosed recurrent patellar dislocation (RPD). With the three-dimensional (3D) CT reconstructed knee, patellar height was qualitatively assessed by the patellar engagement with the femoral trochlea in terminal knee extension to divide RPD population into case (patella alta) and control group. With digitally reconstructed lateral radiographs, patellar height was measured with P-PTP distance (perpendicular distances between the distal edge of patella articular surface and posterior turning point of distal femur), and four commonly used ratios: Caton-Deschamps index, Modified Insall-Salvati index, Blackburne-Peel index, and Insall-Salvati index. An unpaired t-test was conducted to determine significant differences between groups. Correlation coefficient, intra- and inter-observer reliability, receiver operating characteristic (ROC) curves and the area under the ROC curve (AUC) were also calculated. 198 knee images (198 patients) were included for final evaluation. Patella alta was present in 72 knees (36.3%) with RPD. The effect size was relatively large between the case and control group for P-PTP distance (d=-1.619; 95% CI,-1.948 to-1.286). P-PTP distance correlated moderately to strongly with four commonly used ratios (P < .001). Intraobserver and interobserver reliability was good for P-PTP distance. The AUC of the ROC curve was categorized as excellent for P-PTP distance, better than other measurements (P < .001), and the cutoff value was 4.2 mm with the highest sensitivity (86.11%) and specificity (84.92%). The measurement method, P-PTP distance, showed good intra-observer and inter-observer reliability, well correlated with commonly used ratios, and presented best diagnostic accuracy among commonly used ratios for predicting RPD. P-PTP distance might be a potential indicator for identifying patella alta in RPD patients when supine and knee extended. The measurement reported in this study may help in advancing clinical evaluation of patella alta, providing an alternative and simple method to measure patellar height. Standing or weight-bearing plain lateral radiographs obtained from the routine practice should be further assessed in the next step to further validate the method.

THE PATELLA THICKNESS TO FEMORAL TROCHLEA DEPTH RATIO THE AS A CHOICE PREDICTOR OFTHE PATELLAR LUXATION SURGICAL TREATMENT IN DOGS

Patellar luxation (PL) is a surgical pathology of the knee joint, the lack of timely correction of which can lead to the development of comorbid arthropathies associated with joint instability. There are several PL correction surgical methods, the most widely used of which is the transposition of tibial tuberosity combined with trochleoplasty. However, trochleoplasty requires dissection of the joint capsule, which increases surgical trauma, is associated with damage to articular cartilage, because of which the recovery period is prolonged, and the number of postoperative complications increases. Therefore, it is essential that the surgeon determines whether this surgical trauma is necessary. The aim of our study was to determine the value of the P-STOF index (Patella— Sulcus trochleae ossis femoris) in dogs, in which it is necessary to perform trochleoplasty. During the study, 15 cadavers of dogs weighing up to 12 kg were used (mean weight ±SD: 4.7±3.7 kg). The knee joint area radiography in tangential and mediolateral projections was performed on 30 unpaired pelvic limbs of cadavers of dogs to the depth of the femoral trochlear groove (Sulcus trochleae ossis femoris — STOF) and the craniocaudal thickness of the patella. After that, the joints were opened, and measurements were carried out using an electronic caliper. It was found that reliable results are obtained by measuring the depth of STOF by radiographs in the tangential projection and by measuring the craniocaudal thickness of the patella by radiographs in the mediolateral projection. The mean patella thickness to femoral trochlea depth ratio in dogs without knee arthropathies was 3.1±0.2 (the standard error of the mean is indicated) (95% CI 2.7–3.5) and 4.0±0.3 (95% CI 3.4–4.5) in dogs with identified knee arthropathies. Therefore, when the P-STOFF index value is more than 3.4, trochleoplasty is recommended, since this value represents the lower limit of the confidence interval in dogs with arthropathies.

Development of an Auxiliary Device for Patellar and Femoral Joint Tangential Axial Radiographic Imaging and a Method for Obtaining an Optimal Radiographic Image Using the Development.

This study evaluated the accuracy of tangential axial radiography of the patellar and femoral joint using an auxiliary device based on three image evaluation criteria, which we named the patellofemoral joint radiography auxiliary device (PJR). To compare the PJR method with conventional radiographic methods, such as Laurin, Merchant, and Settegast, a whole-body phantom (PBU-31) was used and three image evaluation items were set. The radiographic method, the smallest inclination of the patellar and showed the best half lateral image of the patella, is Settegast, and the measurement is 9.40. The second-best PJR measurement is 9.97, and the difference between the two measures is 5.76% (p = 0.001). The radiographic method showing the image with the largest distance between the patellar and femoral joint space is PJR which a measurement is 12.35. The second best Merchant measure is 10.55, and the difference between the two measures is 14.54% (p = 0.001). The method in which the two bones were well overlapped (i.e., evaluate the distortion of the image by measured as the distance between the femoral trochlear groove and the tibial tuberosity) is the PJR and the measurement is −0.37. The second-best Merchant measure is 3.93, and the difference between the two measures is 91.4% (p = 0.001). The Settegast has the image with the smallest inclination of the patella, but the PJR has the image that best describes the patellar–femoral joint and the least distortion of the image. As a result of the comprehensive evaluation, when using PJR, bending the knee by 40° and setting a 140° angle between the long axis of the femur and the long axis of the lower leg were considered to be the most beneficial conditions. Therefore, we propose the use of PJR for tangential axial radiography of the patellar–femoral joint.

Computed tomographic measurements of the femoral trochlea in dogs with and without medial patellar luxation.

To determine cutoff values in small (SB) and medium/large (MLB) breed dogs with and without medial patellar luxation (MPL) for identifying abnormal femoral trochlea morphology. Original research. A total of 80 computed tomographic (CT) scans from client-owned dogs METHODS: Four groups of 20 dogs were created: (1) control SB, (2) control MLB, (3) MPL-SB, and (4) MPL-MLB. Two authors measured the femoral trochlear groove angle (FTGA), femoral trochlear angle (FTA), and femoral trochlear ridge inclination angle (FTRIA) in two points with CT. ANOVA and ROC-analysis were tested to the control and MPL groups to assess sensitivity, specificity, and cutoff values. Statistical significance was set to p < .05. Intraclass correlation coefficients evaluated the inter-rater agreement. FTGA (± SD) in control SB (128.8° ± 4.7°) and control MLB (119.2° ± 5.6°), was smaller (p < .0001) than in MPL-SB (139.4° ± 4.4°) and MPL-MLB (133.7° ± 5.1°). FTA and FTRIA were decreased (p=.12, p=.23) in MPL-SB (2.1° ± 6.8; -0.3° ± 3.3°) and MPL-MLB (3.8° ± 5.6°; 1.7° ± 4.5°) compared to control SB (0.2° ±4.1; -0.1° ± 2.6°) and control MLB (5.3° ± 2.8°; 3.1° ± 1.3°). Cutoff values for FTGA, FTA, and FTRIA were > 134°, < -5.9°, < -2 ° (SB), and > 128.3°, < -0.4°, < -0.4° (MLB). Sensitivity, specificity, and inter-rater agreement were superior for FTGA than FTA and FTRIA. Dogs without MPL had a deeper femoral trochlear groove than MPL dogs. SB had a shallower groove than MLB. The measurement of FTA and FTRIA was not reliable. A FTGA <134° (SB) and < 128° (MLB) may be considered as a cutoff for trochleoplasty decision-making.

Prospective study on functional and radiological outcome of suprapatellar approach for intramedullary nailing using semi extended knee position in tibial shaft fractures

Fractures of the tibia are one of the most common orthopedic injuries occurring most often in younger patients. Tibial fractures are frequently associated with high energy trauma mechanisms. Intramedullary nailing is one amongst the preferred treatment modalities for mid shaft tibial fractures. Standard Tibial nailing entry portals used are the infrapatellar and parapatellar approaches. Suprapatellar tibial nailing is a recent advance in the surgical technique for treatment of tibial shaft fractures. This method has shown reduced operative and fluoroscopy time and lesser pain incidence in previous studies. The semi extended position of the knee also allows for countering the deforming effect of the musculature pull of the quadriceps mechanism and also easier fluoroscopy imaging. The suprapatellar technique decreases the risk of perforation of posterior cortex by placing the starting point in line with the medullary canal. This technique also helps to reduce Varus and Valgus deformity by using the femoral trochlear groove as a guide to the starting point which maintains the mechanical axis of the lower extremity.Objectives of the study: To assess Functional outcomes of suprapatellar approach in mid shaft tibial fractures by Lower extremity functional score (LEFS).To assess Radiological outcomes of suprapatellar approach in mid shaft tibial fractures by the Radiological Union in Tibia Score (RUST).Study design: Prospective interventional studyStudy period: October 2019 to May 2021Source of data: Patients admitted with closed mid shaft tibial fractures as an inpatient in the Department of Orthopaedics, Victoria hospital and Bowring and Lady Curzon hospitals attached to BMCRI were included in the study satisfying the inclusion and exclusion criteriaMethodology: 20 patients with closed or open (type 1 and 2) mid shaft tibial fractures were treated using the suprapatellar approach. Functional outcome was measured using the Lower extremity functional score and radiological outcome was measured using the Radiological union in tibia score at immediate and last follow up intervals.Results: Our study group comprised of 20 patients between the ages 20 to 60 years. LEFS showed a statistically significant improvement from 23.35 at 6 weeks to 69.25 at 12 months. In our study analysis out of 20 patients, 11 patients had excellent LEFS score, 7 patients had good LEFS score and 2 patients had fair LEFS score. Also in our study 100% patients achieved union by 20 weeks with a mean RUST score of 7.4 at 6 weeks compared to a mean RUST score of 14.15 at 12 months.Conclusion: Suprapatellar nailing has shown shorter fluoroscopy less manoeuvrability and operative time, excellent to fair functional outcome of lower limb and reduced incidence of valgus and varus malalignment postoperatively. Suprapatellar nailing is a promising technique of tibial fracture fixation with satisfactory radiological and functional outcomes postoperatively.

Reduplicated medial parapatellar plica: a case of a medial plica anatomical variation recalcitrant to conservative treatment

PurposeThe current study aims to report the radiologic and clinical appearance of a rare anatomical variation of the knee medial synovial plica along with its response to conservative and surgical treatment.Case presentationThis report portrays a 29-year-old male patient with anteromedial gradual onset right knee pain, aggravated when descending stairs or prolonged sitting. Physical examination revealed medial parapatellar local tenderness, a palpable click in this area when the knee was extended, and hamstring tightness. Magnetic resonance imaging showed a duplicated medial plica, characterized by a high-intensity signal of the infrapatellar fat pad medial portion, after which a presumptive diagnosis of medial plica syndrome was proposed. After conservative treatment failure, the patient underwent standard knee arthroscopy that revealed a superior low profile and an inferior high profile medial plica, and hypertrophy of the medial portion of the infrapatellar fat pad. Both plicae and fat pad were resected with a mechanical shaver until no contact between the femoral trochlea and the fat pad was observed during full range of motion. At 4 weeks postoperatively, symptoms completely resolved, and the patient was allowed to return to full activity with no recurrences at 1 year follow-up.ConclusionsThe current study presented a rare anatomical variation of the knee medial synovial plica that was symptomatic and recalcitrant to conservative treatment. This case report may be useful for radiologists and orthopaedic surgeons to differentiate this special plica type and consider its response to conservative and surgical treatment during patient management.