Visualization of osteochondral fragments in the cavity of the knee joint in case of patellar dislocation in children

The objective was to assess the capabilities of MRI and CT in visualizing free bone and cartilage fragments in the knee cavity after lateral dislocation of the patella. Materials and methods. CT and MRI were performed in 220 patients, including 127 girls and 93 boys aged 12 to 18 years (mean age 14.5 years), with acute lateral patellar dislocation. Results. Lateral dislocation of the patella in 25% of cases led to the appearance of osteochondral fragments. CT scan revealed and confirmed osteochondral fragments surgery in 55 people (100%), MRI scan - in 50 people (90%). The sites of the detachment of the osteochondral fragments were: a medial facet of the patella in 22 (38.8%), the outer edge of femur lateral condyle in 33 (58.2%), t patella and lateral condyle of the femur in 2 patients (3%). Free cartilage fragments not detected by CT were detected by MRI in 2 patients. Conclusion. Patellar dislocation is an injury that is likely to require surgery. The volume of osteochondral and soft tissue lesions can be established with the maximum degree of probability by MRI while detecting small osteochondral fragments is most reliable with CT. Combining these two observation methods provides the complete possible information about the extent of damage, which allows timely resolution of treatment tactics.

High Submandibular Anteroparotid Approach for Open Reduction and Internal Fixation of Condylar Fracture

Aim. There are several techniques for the treatment of mandibular condylar fractures. This is the first report of the high submandibular anteroparotid approach for open reduction and internal fixation of condylar fracture. Materials and Methods. A 41-year-old woman fell indoors and injured her face. She was referred to our department for detailed examination and treatment of a suspected mandibular fracture. X-ray and computed tomography showed a right mandibular condylar base fracture and lateral dislocation of the fracture fragment. Open reduction and internal fixation procedures were performed for a right mandibular condylar fracture under general anesthesia. The mandibular ramus was reached by approaching from the inferior margin of the mandible, delaminating the masseter fascia posteriorly, and bypassing the anterior margin of the parotid gland. Once the fractured bone was reached, reduction and fixation were performed. Results. We have achieved good results by the high submandibular anteroparotid approach, which is minimally invasive and simple, to reduce and fix condylar fractures. With this approach, no facial artery or retromandibular vein was encountered, and the mental stress for the surgeon was minimal. Postoperative wound infection, parotid gland complications such as parotitis and salivary fistula, facial nerve dysfunction such as facial paralysis, and esthetic disorders such as scarring were not observed. Conclusions. Although it is necessary to examine more cases in the future, the high submandibular anteroparotid approach may be useful as a new approach for open reduction and internal fixation of condylar fractures.

Clinical Outcomes and Prognostic Factors in Patients With Recurrent Patellar Lateral Dislocation Treated With Isolated Medial Patellofemoral Ligament Reconstruction: A Retrospective Single-Center Analysis

Background: Medial patellofemoral ligament reconstruction (MPFLR) is widely used to treat patellofemoral instability. However, it is still unclear when a concomitant bony procedure is needed. Purpose: To evaluate the therapeutic efficacy of isolated MPFLR for recurrent patellar lateral dislocation and to identify the prognostic factors for clinical outcomes. Study Design: Case series; Level of evidence, 4. Methods: A total of 237 patients who had undergone unilateral isolated MPFLR between January 2011 and December 2016 were included. Patellar tracking (J sign) and radiologic information including patellar height, trochlear dysplasia, tibial tubercle–trochlear groove distance, and patellar tilt was collected preoperatively, and the Kujala and International Knee Documentation Committee (IKDC) functional scores were used to assess postoperative recovery. Failure was defined as redislocation or patient-reported and clinically confirmed patellar instability. The influence of radiologic features and the J sign on knee functional scores was explored via subgroup analysis. Potential prognostic factors were explored using univariate and multivariate regression analyses, and risk factors for a positive J sign were evaluated using Spearman coefficient correlation analysis. Results: The mean ± SD follow-up period was 70.67 ± 18.05 months (range, 36-108 months). From preoperatively to final follow-up, all patients had statistically and clinically significant improvements in the Kujala score (from 51.43 ± 6.87 to 88.52 ± 4.83; P < .001) and IKDC score (from 49.78 ± 6.05 to 81.16 ± 4.20; P < .001). Subgroup analysis indicated no significant difference in functional score improvements based on radiologic features or the J sign. Overall, 20 knees (8.4%) experienced postoperative failure: 11 with redislocation and 9 with patellar instability. A preoperative positive J sign was shown to be an independent prognostic factor for postoperative failure via logistic regression analyses: univariate (odds ratio, 3.340; 95% CI, 1.316-8.480; P = .011) and multivariate (odds ratio, 3.038; 95% CI, 1.179-7.827; P = .021). In addition, the J sign was closely associated with patellar height ( r S, 0.159; P = .014) and trochlear dysplasia ( r S, 0.235; P < .001). Conclusion: Isolated MPFLR appears to be an effective strategy for recurrent patellar lateral dislocation, with significant functional improvement and a low failure rate. A preoperative positive J sign was identified as a potential prognostic risk factor for postoperative failure.

Hindlimb torsional alignment changes in growing rabbits after patellar dislocation

Background Torsional malalignment has been considered as a risk factor for patellar dislocation. But the influence of patellar dislocation for torsional alignment development remains unknown. The present study aims to investigate whether the torsional alteration of the hindlimb occurs after patellar dislocation in growing rabbits. Methods In the present study, 30 one-month-old rabbits were included. The experimental group consisted of 30 left knees of rabbits which underwent patellar lateral dislocation. The control group consisted of 30 right knees of the rabbits which no surgical procedure was performed. The Computed Tomography (CT) scan was performed after the surgery and at the point the rabbits were skeletal mature (5 months post-surgery). The angles of femoral version and tibial torsion were measured using a three-dimensional method and analyzed between the experimental group and the control group. Results After the surgery, the femoral version and tibial torsion in the experimental and control group were not significantly different. However, 5 months after surgery, the angle of femoral version in the experimental group (-5.50 ± 6.13°) was significantly different from that in the control group (−10.90 ± 4.74°) (P < 0.05). But the angle of tibial torsion in the experimental group (7.17 ± 7.25°) and control group (4.47 ± 6.34°) were not significantly different (P = 0.144). Conclusions From this study, patellar dislocation can lead to alteration of femoral version in growing rabbits. So patellar dislocation may affect on lower extremity alignment. These findings may develop pathology and etiology of patellar dislocation.

Hindlimb torsional alignment changes in growing rabbits after patellar dislocation

Background: Torsional malalignment has been considered as a risk factor for patellar dislocation. But the influence of patellar dislocation for torsional alignment development remains unknown. The present study aims to investigate whether the torsional alteration of the hindlimb occurs after patellar dislocation in growing rabbits. Methods: In the present study, 30 one-month-old rabbits were included. The experimental group consisted of 30 left knees of rabbits which underwent patellar lateral dislocation. The control group consisted of 30 right knees of the rabbits which no surgical procedure was performed. The Computed Tomography (CT) scan was performed after the surgery and at the point the rabbits were skeletal mature (5 months post-surgery). The angles of femoral version and tibial torsion were measured using a three-dimensional method and analyzed between the experimental group and the control group. Results: After the surgery, the femoral version and tibial torsion in the experimental and control group were not significantly different. However, 5 months after surgery, the angle of femoral version in the experimental group (-5.50 ± 6.13°) was significantly different from that in the control group (-10.90 ± 4.74°) (P < 0.05). But the angle of tibial torsion in the experimental group (7.17 ± 7.25°) and control group (4.47 ± 6.34°) were not significantly different (P = 0.144). Conclusion: From this study, patellar dislocation can lead to alteration of femoral version in growing rabbits. So patellar dislocation may affect on lower extremity alignment. These findings may develop pathology and etiology of patellar dislocation.

Hindlimb torsional alignment changes in growing rabbits after patellar dislocation

Background: Torsional malalignment has been considered as a risk factor for patellar dislocation. But the influence of patellar dislocation for torsional alignment development remains unknown. The present study aims to investigate whether the torsional alteration of the hindlimb occurs after patellar dislocation in growing rabbits.Methods: In the present study, 30 one-month-old rabbits were included. The experimental group consisted of 30 left knees of rabbits which underwent patellar lateral dislocation. The control group consisted of 30 right knees of the rabbits which no surgical procedure was performed. The Computed Tomography (CT) scan was performed after the surgery and at the point the rabbits were skeletal mature (5 months post-surgery). The angles of femoral version and tibial torsion were measured using a three-dimensional method and analyzed between the experimental group and the control group.Results: After the surgery, the femoral version and tibial torsion in the experimental and control group were not significantly different. However, 5 months after surgery, the angle of femoral version in the experimental group (-5.50 ± 6.13°) was significantly different from that in the control group (-10.90 ± 4.74°) (P < 0.05). But the angle of tibial torsion in the experimental group (7.17 ± 7.25°) and control group (4.47 ± 6.34°) were not significantly different (P = 0.144).Conclusion: From this study, patellar dislocation can lead to alteration of femoral version in growing rabbits. So patellar dislocation may affect on lower extremity alignment. These findings may develop pathology and etiology of patellar dislocation.

The torsional alignment changed significantly of hindlimb in growing rabbits after patellar dislocation

Background Torsional malalignment has been considered as a risk factor for patellar dislocation. But the influence of patellar dislocation for torsional alignment development remains unknown. The present study aims to investigate whether the torsion alteration of the hindlimb occur after patellar dislocation in growing rabbits. Methods In the present study, 30 one-month old rabbits were included. The experimental group consists of 30 left knees of rabbits and were underwent patellar lateral dislocation. And the control group consists of 30 right knees and no surgical procedure was performed. The Computed Tomography (CT) scan was performed on each knee when the surgery was finished and at the time the rabbits were skeletal mature (5 months post-surgery). The angles of femoral version and tibial torsion were measured using a three-dimensional method and analyzed between the experimental group and control group. Results The femoral version and tibia torsion in the experimental and control group immediately after surgery were not significantly different. However, 5 months after surgery, the femoral version angle of the experimental group (-5.50±6.13°) was significantly different with that of the experimental group (-10.90±4.74°)( P < 0.05). But the tibia torsion angle in the experimental group (7.17±7.25°) and control group (4.47±6.34°) were not significantly different ( P = 0.144). Conclusion From this study, patellar dislocation can lead to alteration of femoral version in growing rabbits. This may indicate the early treatment for patellar dislocation in children is particularly important to avoid torsional malalignment in the future. These findings may develop pathology and etiology of patellar dislocation.