Depth Of Trochlear Groove Research Articles

Quantitative magnetic resonance imaging in patellar tendon-lateral femoral condyle friction syndrome: relationship with subtle patellofemoral instability.

To investigate the correlation of patellar tendon-lateral femoral condyle friction syndrome (PTLFCFS) with subtle patellofemoral instability to explore its pathogenesis. One hundred knees of 80 patients with PTLFCFS were analyzed retrospectively by retrieving magnetic resonance imaging (MRI) data over a 3-year period from our database. Seven quantitative parameters for evaluating patellofemoral stability were measured on MR images, including the Insall-Salvati ratio, tibial tuberosity-trochlear groove (TT-TG) distance, trochlear groove depth, medial trochlear/lateral trochlear length (MT/LT) ratio, medial trochlear/lateral trochlear height (MH/LH) ratio, lateral patellofemoral angle (LPA), and lateral trochlear inclination (LTI) angle. These patellofemoral parameters of the PTLFCFS group and the normal control group were compared (n = 88), and receiving-operator characteristic (ROC) curve analysis was conducted to determine the specificity and sensitivity of these parameters. The trochlear depth, MT/LT, LPA, and LTI angle were significantly lower (p < 0.001) and the Insall-Salvati ratio was significantly higher (p < 0.001) in the PTLFCFS group. However, the TT-TG distance and MH/LH ratio showed no significant difference (p = 0.231 and 0.073 respectively). The area under the ROC curve of the Insall-Salvati ratio, trochlear depth, MT/LT, LPA, and LTI angle were 0.925, 0.784, 0.8, 0.731, and 0.675 respectively. The efficiency of the Insall-Salvati ratio was the highest among those five parameters. This study verified the presence of subtle patellofemoral instability by measuring various patellofemoral parameters in patients with PTLFCFS. It confirmed that PTLFCFS is associated with subtle patellofemoral instability and could largely explain the pathogenesis of PTLFCFS.

Computed Tomographic Trochlear Depth Measurement in Normal Dogs.

The main purpose of this study was to describe the relationship between patellar maximal craniocaudal thickness and femoral trochlear groove depth in normal dogs and to valuate the intra-observer or inter-observer variability of maximal trochlear depth and maximal patellar craniocaudal thickness using computed tomography. Trochlear groove depth and patellar maximal craniocaudal thickness of 40 limbs (20 dogs) were measured by three independent veterinarians using three-dimensional multiplanar reconstruction computed tomography images. The patellar maximal craniocaudal thickness/trochlear depth ratio was determined. The mean ratio of these stifles was 0.46 (range 0.24-0.70), meaning that the mean maximal depth of the trochlea was 46% of the mean maximal-patellar thickness. A wide range of maximal-patellar-craniocaudal-thickness/maximal trochlear-depth ratio was found suggesting that breed studies should be performed to determine a breed-specific patellar-thickness/trochlear-depth ratio. To make decisions on when and where to perform a sulcoplasty during patellar luxation surgery, patella/trochlea thickness relationship should be measured for each breed with patellar tracking from stifle hyperflexion to stifle hyperextension.

Changes in femoral trochlear morphology following surgical correction of recurrent patellar dislocation associated with trochlear dysplasia in children.

The aim of this study was to investigate the changes in femoral trochlear morphology following surgical correction of recurrent patellar dislocation associated with trochlear dysplasia in children. A total of 23 patients with a mean age of 9.6 years (7 to 11) were included All had bilateral recurrent patellar dislocation associated with femoral trochlear dysplasia. The knee with traumatic dislocation at the time of presentation or that had dislocated most frequently was treated with medial patellar retinacular plasty (Group S). The contralateral knee served as a control and was treated conservatively (Group C). All patients were treated between October 2008 and August 2013. The mean follow-up was 48.7 months (43 to 56). Axial CT scans were undertaken in all patients to assess the trochlear morphological characteristics on a particular axial image which was established at the point with the greatest epicondylar width based on measurements preoperatively and at the final follow-up. Preoperatively, there were no statistically significant differences between the trochlear morphology in the two groups (sulcus angle, p 0.852; trochlear groove depth, p 0.885; lateral trochlear inclination, p 0.676; lateral-to-medial facet ratio, p 0.468; lateral condylar height, p 0.899; medial condylar height, p 0.816). Many radiological parameters of trochlear morphology were significantly different between the two groups at the final follow-up, including well-known parameters, such as the mean sulcus angle (Group S, 146.27° (sd 7.18); Group C, 160.61° (sd 9.29); p < 0.001), the mean trochlear groove depth (Group S, 6.25 mm (sd 0.41); Group C, 3.48 mm (sd 0.65); p < 0.001) and the mean lateral trochlear inclination (Group S, 20.99° (sd 3.87); Group C, 12.18° (sd 1.85); p < 0.001). Lesser known parameters such as the ratio of the lateral to medial trochlear length (Group S, 1.46 (sd 0.19); Group C, 2.14 (sd 0.42); p < 0.001), which is a measurement of facet asymmetry, and the lateral and medial condylar height were also significantly different between the two groups (p < 0.001). The femoral trochlear morphology can be improved by early (before epiphyseal closure) surgical correction in children with recurrent patellar dislocation associated with femoral trochlear dysplasia. Cite this article: Bone Joint J 2018;100-B:811-21.

Patellar tracking should be taken into account when measuring radiographic parameters for recurrent patellar instability.

To date, many radiographic parameters on patellar instability have their measurements taken statically, and have not been studied in various degrees of flexion according to the patellar tracking. There are also limited data regarding the use of these parameters in predicting recurrent patellar dislocation. The current study aims to review the radiographic parameters of the patellofemoral joint in different degrees of knee flexion and to correlate them with the presence of recurrent instability. A 10-year retrospective study was conducted on all patients who had computed tomography patellar-tracking scan done for patellar instability when aged 18years or younger. The computed tomography patellar-tracking scans were performed with the knee in extension, 10° flexion, and 20° flexion. The axial radiographic parameters were evaluated at the patellar equator, roman arch, and distal patellar pole. Sagittal and coronal parameters were noted. Radiographic parameters were then correlated with recurrent patellar instability. The femoral sulcus angle and trochlear groove depth at the distal patellar pole in 10° knee flexion (p value 0.04 and 0.03, respectively) and patellar equator in 20° knee flexion (p value 0.02 and 0.03, respectively) had the most significant clinical correlations with recurrent instability on multivariate analysis. Other radiographic parameters found to have significant clinical correlation on univariate analysis include the patellar tilt angle, congruence angle, femoral sulcus angle, trochlear groove depth, and Wiberg's classification. As per the knee dynamics, axial radiographic parameters had the most significant correlation with recurrent patellar instability when measured at the distal patellar pole in 10° knee flexion and at the patellar equator in 20° knee flexion. Future axial radiographic evaluation of patellofemoral instability should then be performed at these degrees of knee flexion and axial cuts. Trochlear dysplasia, as measured by the femoral sulcus angle and trochlear groove depth, was the most significant predictor of recurrent patellar instability in the skeletally immature. Wiberg's classification was also a novel factor found to have clinical correlation with patellofemoral instability. III.

The significance of magnetic resonance imaging in severe femoral trochlear dysplasia assessment.

The clinical diagnosis of femoral trochlear dysplasia primarily relies on imaging. In the past, plain imaging was the major source of diagnosis. The present study investigated the application of magnetic resonance imaging (MRI) in the objective assessment of severe femoral trochlear dysplasia. A retrospective analysis was performed on knee MRIs from 30 normal subjects (30 knees) and 59 patients (61 knees) with severe femoral trochlear dysplasia based on the Dejour morphological classification. Cartilage and subchondral bone landmarks were used to compare a series of measurements between patient and control groups. These measurements included the femoral trochlear groove depth, sulcus angle, the lateral trochlear inclination, trochlear facet asymmetry, the femoral medial and lateral condyle symmetry, and the ratios between the femoral medial/lateral condyles and the maximal trochlear width. The measurement values based on the two types of landmarks were also compared within the patient and control groups, separately. In addition, the femoral trochlear groove depth, sulcus angle, lateral trochlear inclination and trochlear facet asymmetry of patients with different Dejour types were compared. Significant differences were observed in the femoral trochlear groove depth, sulcus angle, lateral trochlear inclination and trochlear facet asymmetry between the patient and control groups (P<0.05). Based on the two types of landmark, all indexes were significantly different (P<0.05; with the exception of lateral trochlear inclination) between the patient and control groups. Among patients with various Dejour types, the femoral trochlear groove depth, sulcus angle, lateral trochlear inclination and trochlear facet asymmetry demonstrated no significant differences. MRI exhibited advantages in revealing articular cartilage over conventional radiography and computed tomography. Therefore, cartilage landmarks in MRI images may be utilized to objectively evaluate femoral trochlear dysplasia in patients with severe femoral trochlear dysplasia.

Imaging characteristics of contralateral asymptomatic patellofemoral joints in patients with unilateral instability.

To test the hypothesis that in patients with unilateral patellofemoral instability ( PI patellofemoral instability ), the contralateral asymptomatic joints have abnormal morphology and imaging features of osteoarthritis ( OA osteoarthritis ) at four-dimensional ( 4D four-dimensional ) computed tomography (CT). The institutional review board approved this HIPAA-compliant retrospective study. Informed consent was waived. Radiology records were reviewed to identify 25 patients (male-female ratio, 0.56; median age, 20 years; range, 13-43 years) with unilateral PI patellofemoral instability undergoing 4D four-dimensional CT and 25 age- and sex-matched control patients undergoing multidetector CT. Trochlear groove depth ( TGD trochlear groove depth ), tibial tuberosity-trochlear groove ( TT-TG tibial tuberosity-trochlear groove ) distance, and patellar height ratio ( PHR patellar height ratio ) were determined to compare morphology, and bisect offset ( BO bisect offset ) measurements were obtained to compare lateral displacement of the patella between the two groups by using the Wilcoxon rank-sum test. All images were interpreted by trained observers. Tracking patterns of the patellae were determined by obtaining BO bisect offset measurements at various flexion angles with 4D four-dimensional CT. In the contralateral asymptomatic joints, TGD trochlear groove depth (median, 3.0 mm; 95% confidence interval [ CI confidence interval ]: 2.5, 4.6; P < .0001), TT-TG tibial tuberosity-trochlear groove (median, 15 mm; 95% CI confidence interval : 12.7, 18; P = .008), PHR patellar height ratio (median, 1.17; 95% CI confidence interval : 1.09, 1.2; P = .002), and patellar lateral displacement ( BO bisect offset , 85%; 95% CI confidence interval : 76.2%, 98.2%; P < .0001) were different from measurements obtained in the control group: TGD trochlear groove depth median, 5.0 mm (95% CI confidence interval : 2.2, 7.6); TT-TG tibial tuberosity-trochlear groove median, 10.9 mm (95% CI confidence interval : 3.4, 20.7); PHR patellar height ratio median, 0.92 (95% CI confidence interval : 0.67, 1.36); and BO bisect offset median, 63% (95% CI confidence interval : 59%, 68.4%). OA osteoarthritis was detected in 40% of asymmetrical contralateral joints (10 of 25). By using 4D four-dimensional CT data, multiple regression analysis demonstrated that TGD trochlear groove depth (P = .026) and BO bisect offset measurements obtained at 30° of knee flexion (P = .047) had an association with the presence of OA osteoarthritis . Abnormal morphology and imaging features of OA osteoarthritis are relatively common in contralateral asymptomatic joints of young patients with unilateral PI patellofemoral instability .

CT study of femoral trochlear groove anatomical morphology

Objective To explore the anatomical morphology of femoral trochlear groove and the difference between normal males and females.Methods Eighty healthy volunteers were recruited,including 42 males and 38 females with an average age of 36.2 years (range,21-55 years).All the volunteers without knee unstabilization,pain and wound.CT scan of right femurs were performed and 3-D model were reconstructed.The anatomical parameters of right femoral trochlear groove were measured,which included transepicondylar axis,medial and lateral length of trochlear groove,medial and lateral condylar height,sulcus angle,depth of trochlear groove,transcondylar axis,anterior femoral condylar angle,trochlear groove position,and then compared the morphologic difference of trochlear groove between males and females.Results The average width of transepicondylar axis was 79.21±3.80 mm for males and 70.73±2.91 mm for females (t=-53.40,P=0.00).The minimum sulcus angle was acquired at 45° flexion for males and 42° flexion for females.It was 133.92°±4.76° for males and 132.71°±4.36° for females.The maximum length of transepicondylar axis was acquired at 87° flexion for males and 90° flexion for females.It was 42.36±3.48 mm for males and 39.03 ±3.36 mm for females.The anterior femoral condylar angle decreased with the increasing flexion angle of knee (P＞0.05).The position of the trochlear groove moved laterally with the increasing flexion angle of knee (P＞0.05).Conclusion There is no significant difference between male and female in the geometry of femoral trochlear groove,however there is a significant difference in sizes.Therefore,during design the knee prosthesis,close approximation of size is essential,while gender differences in morphology need not be considered a factor. Key words: Patella; Tomography, X-ray; Anatomy; Sex factors

Evaluation of trochlear dysplasia using MRI: correlation between the classification system of Dejour and objective parameters of trochlear dysplasia

Trochlear dysplasia is considered to be one of the major factors causing patellofemoral instability (PFI). Dejour's classification is widely used to assess the severity of trochlear dysplasia. Additionally, in current literature, different quantitative parameters are recommended to distinguish between a normal trochlea and a dysplastic trochlea. In order to achieve a more objective evaluation of the trochlea, the aim of this study was to evaluate whether specific measurements of the femoral trochlea can be assigned to the qualitative classification system of Dejour. Transverse MRI T2-weighted scans of 80 knees with symptomatic PFI and varying severity of trochlear dysplasia were classified according to Dejour (type A to D). For all MRI scans, quantitative measurements with parameters as described in the literature were applied. The values were then allocated to Dejour's classification. In addition to the four-grade analysis, two-grade analysis was also performed (Dejour type A against type BCD). Dependent on the cut-off values, specificity, sensitivity and Youden index for each parameter was defined. The allocation resulted in the following distribution: type A trochlear dysplasia n = 25, type B n = 23, type C n = 18 and type D n = 14. In descriptive statistics, none of the measurements proposed in the literature could be assigned to the four-grade classification system of Dejour. For the two-grade analysis at the cut-off, sensitivity ranged from 75 to 86 % and specificity from 76 to 84 % for lateral trochlear inclination, trochlear facet asymmetry and depth of trochlear groove. All other measurements showed a poor sensitivity ranging from 49 to 67 % and specificity from 40 to 72 %. Interobserver and intraobserver repeatability for the measured parameters was fair to moderate (ICC values 0.34-0.58) in high-grade dysplasia (type BCD) and substantial to almost perfect (ICC values 0.71-0.88) in low-grade trochlear dysplasia (type A). Quantitative measurements of the femoral trochlea have shown to be of limited value for the assessment of trochlear dysplasia. None of the quantitative measurements of the trochlea on transverse images could be assigned to the four-grade descriptive classification of trochlear dysplasia of Dejour. Additionally, measurements could not be reliably performed in high-grade trochlear dysplasia. However, trochlear inclination, trochlear facet asymmetry and depth of trochlear groove may help to distinguish between low-grade and high-grade dysplasia.

Correlation Between Trochlear Groove Depth and Patellar Position During Open and Closed Kinetic Chain Exercises in Subjects With Anterior Knee Pain

The purpose of this study was to correlate the trochlear shape and patellar tilt angle and lateral patellar displacement at rest and maximal voluntary isometric contraction (MVIC) exercises during open (OKC) and closed kinetic chain (CKC) in subjects with and without anterior knee pain. Subjects were all women, 20 who were clinically healthy and 19 diagnosed with anterior knee pain. All subjects were evaluated and subjected to magnetic resonance exams during OKC and CKC exercise with the knee placed at 15, 30, and 45 degrees of flexion. The parameters evaluated were sulcus angle, patellar tilt angle and patellar displacement using bisect offset. Pearson's r coefficient was used, with p < .05. Our results revealed in knee pain group during CKC and OKC at 15 degrees that the increase in the sulcus angle is associated with a tilt increase and patellar lateral displacement. Comparing sulcus angle, patellar tilt angle and bisect offset values between MVIC in OKC and CKC in the knee pain group, it was observed that patellar tilt angle increased in OKC only with the knee flexed at 30 degrees. Based on our results, we conclude that reduced trochlear depth is correlated with increased lateral patellar tilt and displacement during OKC and CKC at 15 degrees of flexion in people with anterior knee pain. By contrast, 30 degrees of knee flexion in CKC is more recommended in rehabilitation protocols because the patella was more stable than in other positions.

Objective patellar instability: MR-based quantitative assessment of potentially associated anatomical features

To evaluate and compare the diagnostic utility of multiple quantitative parameters as measured on knee magnetic resonance (MR) examinations of patients suffering objective patellar instability (OPI). We performed a retrospective evaluation of knee MR examinations in a group of 46 patients (59 knees) with clinically proven OPI, and in a control group of 69 patients (71 knees). Multiple quantitative parameters in both groups were statistically evaluated and compared for their association with OPI. OPI patients tend to present shallower trochlear groove (<5 mm), larger Insall-Salvati index (>1.2), shorter patellar nose (<9 mm), smaller morphology ratio (<1.2), and larger patellar tilt (>11 degrees ) than control patients. The best sensitivities were those of the lateral patellar tilt (92.7%), the trochlear groove depth at the roman arch level (85.7%) and the Insall-Salvati index (78%). The best specificities were those of the morphology ratio (86.9%), the patellar nose (84.5%) and the patellar tendon length (84.5%). Shallow trochlear groove may be confidently identified at the roman arch view in OPI patients. Patella alta may be more reliably detected by the Insall-Salvati index in OPI patients. Patellar nose and morphology ratio are very specific indicators of OPI. A short patellar nose (that is to say, a patellar nose ratio of <0.25) has a high association with OPI. Lateral patellar tilt remains the single feature with the highest sensitivity and specificity for identifying OPI patients.

Pre‐ and Postoperative Radiographic and Computed Tomographic Evaluation of Dogs with Medial Patellar Luxation

To quantify, using radiographic and computed tomographic (CT) techniques, the effects of surgical procedures most commonly combined to treat dogs with medial patellar luxation (MPL). Prospective study. Six dogs with 8 MPL were studied. Radiographs and CT of the pelvic limbs were obtained before and immediately after soft-tissue reconstruction, trochlear wedge recession, and tibial crest transposition. Radiographic measurements included angle of inclination, Norberg angle, quadriceps angle (QA), anteversion angle, ratio of the length of the patellar tendon (PT) to the length of the patella, and change in patella tendon angle. CT measurements included angle of inclination, Norberg angle, QA, anteversion angle, depth of the femoral trochlear groove, ratio of the middle femoral trochlear groove depth to the patella thickness, and tibial crest alignment. Conformation of the coxofemoral joint was not affected by surgery. Surgical treatment corrected the QA by 33-58%. Trochlear wedge recession was most effective in deepening the proximal trochlea by 103.5%. The ratio of the middle femoral trochlear groove depth to the thickness of the patella postoperatively resulted in 50% coverage of the patella. Tibial crest transposition resulted in caudalization of the PT by 8.5+/-3.0 degrees, with lateralization of the tibial tuberosity of 11.3 degrees. The effects of surgery for MPL can be quantified with radiographic and CT measurements. Surgical correction restored the alignment of the quadriceps and adequately deepened the femoral trochlear groove. Tibial crest transposition resulted in caudalization of the patella tendon and lateralization of the tibial tuberosity. These pilot data quantified the effects of surgical procedures most commonly combined to treat MPL. We hope to use these measurements to correlate surgical treatment with functional outcome and postoperative occurrence of luxation.