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Background: Research on the cause of lateral patellar dislocation (LPD) has focused on trochlear morphologic parameters, joint alignment, and patellofemoral soft tissue forces. A paucity of information is available regarding how patellar morphologic parameters influence the risk for LPD. Purpose/Hypothesis: The purpose was to assess whether patellar morphology is a risk factor for recurrent LPD. It was hypothesized that (1) patients with recurrent LPD would have decreased patellar width and volume and (2) patellar morphologic parameters would accurately discriminate patients with recurrent LPD from controls. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: A total of 21 adults with recurrent LPD (age, 29.7 ± 11.1 years; height, 170.8 ± 9.9 cm; weight, 76.1 ± 17.5 kg; 57% female) were compared with 21 sex- and height-matched controls (age, 27.2 ± 6.7 years; height, 172.0 ± 10.6 cm; weight, 71.1 ± 12.8 kg; 57% female). Three-dimensional axial fat-saturated magnetic resonance imaging scans were used to measure patellar medial, lateral, and total width; patellar volume; patellar medial and lateral facet length; the Wiberg index; and previously validated knee joint alignment and femoral shape measurements (eg, tibial tuberosity to trochlear groove distance, trochlear dysplasia). Results: The LPD group demonstrated reduced medial patellar width (Δ = −3.6 mm; P <.001) and medial facet length (Δ = −3.7 mm; P <.001) but no change in lateral width or facet length. This resulted in decreased total patellar width (Δ = −3.2 mm; P =.009), decreased patellar volume (Δ = −0.3 cm3; P =.025), and an increased Wiberg index (Δ = 0.05; P <.001). No significant differences were found for all other patellar shape measures between cohorts. Medial patellar width was the strongest single discriminator (83.3% accuracy) for recurrent LPD. Combining medial patellar width, patellofemoral tilt, and trochlear groove length increased the discrimination to 92.9%. Conclusion: The medial patellar width was significantly smaller in patients with recurrent LPD and was the single most accurate discriminator for recurrent LPD, even compared with traditional trochlear shape and joint alignment measures (eg, trochlear dysplasia, patella alta). Therefore, medial patellar morphology should be assessed in patients with LPD as a risk factor for recurrence and a potential means to improve treatment. [ABSTRACT FROM AUTHOR]

Background: Accurate allograft matching is deemed critical for meniscal transplantation; thus, precise measurements are essential to correctly calculate meniscal size. Several methods for meniscal sizing have been described, but there remains a discussion on which is the most accurate for the lateral meniscus. Purpose: To compare the accuracy of radiographic, anthropometric, and magnetic resonance imaging (MRI) methods of determining width and length of the lateral meniscus with actual dimensions after anatomic dissection. Study Design: Controlled laboratory study. Methods: Ten fresh-frozen human cadaveric knees without any evidence of meniscal or ligamentous injury were primarily imaged using radiography and MRI and subsequently underwent dissection to assess the anatomic size of each meniscus. Four methods were used to predict the size of the lateral menisci: anthropometric, radiographic (Pollard and Yoon), and MRI. Absolute differences in length and width between actual and predicted sizes were determined. Results: The anatomic lateral meniscal width and length were 33.01 ± 4.25 mm (mean ± SD; range, 24.84-40.18 mm) and 31.41 ± 5.06 mm (range, 25.2-40.05 mm), respectively. Regarding width, the anthropometric method demonstrated an absolute difference from anatomic measurement significantly greater when compared with the Pollard technique and MRI (P =.002). Regarding length, the Pollard method presented an absolute difference significantly greater than all other techniques (P =.003). In terms of the ability to measure width and length, MRI accurately predicted meniscal size within 10% of the anatomic size in 65% of measurements, the Yoon method in 54%, and the Pollard method in 20% (P =.01). Radiographs tended to overestimate the true size of the lateral meniscus, while the anthropometric technique overestimated width in all specimens. Conclusion: This study demonstrated that MRI and the Yoon radiographic method are comparable in terms of accuracy for graft sizing before lateral meniscal transplantation. While MRI is useful, a contralateral MRI is required, which makes the Yoon radiographic method recommended given the ease and cost advantage. The original Pollard technique and the anthropometric method are not recommended. Clinical Relevance: Over- and undersizing of meniscal transplants has been implicated in graft failure. Therefore, increasing the reliability of preoperative meniscal measurements is deemed important for the success of meniscal allograft transplantation. [ABSTRACT FROM AUTHOR]

Background: Although the size of the meniscal allograft is crucial during meniscal transplantation, the accuracy of meniscal measurement methods is still under debate. A number of methods based on radiographic and magnetic resonance imaging (MRI) data as well as on anthropometric data have been proposed, but their reproducibility and reliability are still unclear. Purpose: To compare meniscal length and width as measured by different techniques (anthropometric and plain radiographic) to establish which of these 2 methods is more reliable and cost-effective for determining the meniscal size in comparison to MRI. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: The MRI scans and plain radiographic films of 22 patients (44 knees) from a single institution were studied. The width and length of the medial and lateral menisci were measured using specific techniques. Data on sex, age, body weight, and height were used to develop a regression formula for meniscal measurements (comparing both imaging methods) to establish meniscal dimensions. Data validation was achieved using the Pearson correlation, the intraclass correlation coefficient, and the Wilcoxon nonparametric test for all variables, with a significance level established at 95%. Accuracy was established as a 10% measure discrepancy from the gold standard (MRI) and was considered an average between the right and left knees. Results: No statistically significant difference was observed between the right and left knees on radiographic and MRI measurements. The Pollard technique of radiographic measurement overestimated the width of the lateral meniscus when compared with anthropometric measurements (P < .001), considering MRI as the gold standard. The same was observed for MRI measurements of the length of the lateral meniscus in which not only anthropometric but also plain radiographic measurements using the Yoon technique were significantly smaller than those values found with the Pollard technique (P < .001). The anthropometric method underestimated the width and length of the medial meniscus with an accuracy of 68.2% and 63.6%, respectively. The radiographic method was comparable with MRI in establishing all medial meniscal measurements with an accuracy of 93.2% for length and 77.3% for width. Conclusion: Some viable alternatives to MRI have been suggested. For the lateral meniscus, anthropometric data are an alternative for width, and the Yoon method can be used to assess length. For the medial meniscus, the Pollard method is considered a satisfactory alternative. This study emphasized the importance of measuring the width and length of the meniscus independently during preoperative sizing for a meniscal allograft transplantation procedure. Using MRI as a gold standard, the study also proposed other less costly and satisfactory methods of obtaining such measurements. [ABSTRACT FROM AUTHOR]

The article presents research which examined the postoperative morphological features of repaired labrum located at various glenoid areas. Topics covered include the restoration of labrum and importance of arthroscopic bankart repair to labrum. Also mentioned is the participation of 46 patients in the study who had arthroscopic Bankart repair.

Background: Successful meniscus transplantation depends on an accurate sizing of the meniscal allograft. Although accurate sizing of the meniscal allograft is crucial during meniscus transplantation, the accuracy of meniscal measurement methods is still in debate.Purpose: This study was undertaken to evaluate the relationship between the width and length of the lateral meniscus. These anatomic dimensions were also evaluated in the context of the patient’s height, weight, gender, and body mass index (BMI).Study Design: Descriptive laboratory study.Methods: Ninety-one samples of fresh lateral meniscus were obtained during total knee arthroplasty. The samples were obtained carefully without injuring the meniscus itself and the bony attachment sites. For each lateral meniscus, the anatomic dimensions (width [LMW] and length [LML]) were recorded. The height, weight, gender, and BMI of the patients were also recorded. The Pearson correlation and multivariate and linear regression analysis were applied for each variable. The accuracy was defined as those measures that fell within 10% of the original size. A P value ≤ .05 was considered significant.Results: The mean LMW was 30.7 mm (standard deviation [SD] = 3.5) and 27.0 mm (SD = 2.6) for men and women, respectively. The mean LML was 33.7 mm (SD = 4.3) and 30.8 mm (SD = 2.6) for men and women, respectively. Thirty-nine samples (42.5%) showed LMW measurements within a 10% difference of LML, whereas 50 samples (55%) showed an LMW greater than a 10% difference of LML. Although there were correlations between LML with LMW in men and correlations between weight and LMW with LML in women, the accuracy for the derived linear regression formulas was 3%, 9%, and 12%, respectively.Conclusion: The length cannot be predicted accurately from the width of the lateral meniscus. The height, weight, gender, and BMI failed to estimate the dimensions of the lateral meniscus. Therefore, it is essential to measure the width and length separately and match it with the allograft with other size measuring methods.Clinical Relevance: This study emphasizes the importance of measuring the width and length of the lateral meniscus independently during preoperative sizing for a meniscal allograft transplantation procedure. The height, weight, gender, and body mass index may not be reliable parameters for estimating the size of the meniscus. [ABSTRACT FROM AUTHOR]