Decreased Posterior Tibial Slope and Its Association With Pediatric Posterior Cruciate Ligament Injury.

BACKGROUND: Recent adult studies have demonstrated that decreased posterior tibial slope angle (PTSA) may be a risk factor for posterior cruciate ligament (PCL) injury. However, there is no study investigating this phenomenon in a pediatric population. Understanding risk factors for PCL injuries among a pediatric population is important given the recent rise in athletic competition/specialization and sports-related injuries. HYPOTHESIS/PURPOSE: The purpose of this study was to compare PTSA between pediatric patients sustaining a primary PCL tear compared with age- and sex-matched controls. It was hypothesized that pediatric patients sustaining a PCL tear would have a decreased PTSA compared with controls, with decreased PTSA being associated with higher odds of PCL injury. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: The records of all patients sustaining a PCL injury between 2006 and 2021 at a level 1 pediatric trauma center were reviewed. Patients aged ≤18 years with magnetic resonance imaging-confirmed PCL tear were included. Excluded were patients with concomitant anterior cruciate ligament tears, previous PCL reconstruction, or previous coronal plane realignment. A control cohort, with their ligament shown as intact on magnetic resonance imaging scans, was matched based on age and sex. PTSA was measured on lateral radiographs of the injured knee or tibia. The mean PTSA was compared between cohorts, and odds ratios were calculated based on the normal slope range (7°-10°) described in the literature, an upper range (>10°), and a lower range (<7°). Inter- and intrarater reliability were determined via calculation of an intraclass correlation coefficient. RESULTS: Of the 98 patients who sustained a PCL injury in this study period, 59 (60%) met inclusion criteria, and 59 healthy knee controls were matched. There were no differences between the cohorts for age (P = .90), sex (P > .99), or body mass index (P = .74). The PCL cohort had a lower mean ± SD PTSA compared with the control group (5.9°± 2.7° vs 7.3°± 4.3°; P = .03). PTSA <7° was associated with a 2.8 (95% CI, 1.3-6.0; P = .01) times risk of PCL tear. Conversely, PTSA >10° was associated with a 0.27 (95% CI, 0.09-0.81; P = .02) times risk of PCL tear. These PTSA measurements demonstrated acceptable intrarater and interrater reliability. CONCLUSION: PTSA <7° was associated with an increased odds of PCL injury, whereas a slope >10° was associated with a decreased odds of PCL injury in a pediatric population. These findings corroborate similar outcomes in adult studies; however, further studies are needed to elucidate PTSA as a risk factor for PCL injury.

The Anterior Modified San Diego Acetabuloplasty Does Not Increase Superior-Anterior Coverage in Patient-Specific 3D-Printed Models.

BACKGROUND: Patients with developmental dysplasia of the hip may require pelvic osteotomies to improve acetabular coverage. The purpose of this study was to compare the changes in acetabular version, tilt, and regional coverage angles following the San Diego acetabuloplasty (SDA), the modified San Diego acetabuloplasty (mSDA), and the Pemberton acetabuloplasty (PA). METHODS: Fourteen patients with developmental dysplasia of the hip and computed tomography (CT) imaging were identified. From CT images, 2 identical pelvises were 3-dimensional-printed for each patient. Bone was printed with rigid material, and cartilage with flexible material. For each model pair, the SDA was performed on one and the PA was performed on the other. CT scans were obtained before and after acetabuloplasties. Next, the bone graft in the SDA model was moved anteriorly, representing the mSDA, and the model was rescanned. Acetabular version, tilt, and coverage angles (posterior, superior-posterior, superior, superior-anterior, and anterior) were calculated. Preoperative to postoperative differences were compared (repeated measures analysis of variance or Wilcoxon signed rank test). The significance was set to P <0.05. RESULTS: The mean age at CT was 5.8±1.2 years (range: 3.9 to 7.5 y). All 3 procedures (SDA, mSDA, and PA) significantly increased acetabular tilt; P <0.045), with a similar change observed for all 3 ( P =0.868). PA was the only procedure to significantly decrease relative acetabular version (6.5±6.5 degrees, preoperative: 12.9±5.3 degrees; P =0.004). Both the SDA and mSDA procedures significantly increased coverage in the superior-posterior octant (SDA: 92.6±9.3 degrees, mSDA: 92.3±9.8 degrees, preoperative: 81.9±9.5 degrees; P <0.02), with a similar percent change among the 2 ( P =1.0). All 3 procedures significantly increased superior coverage ( P <0.04); the increase was similar among the 3 ( P =0.205). The PA was the only procedure to produce a significant increase in coverage in the superior-anterior octant (91.0±16.7 degrees, preoperative: 74.0±12.1 degrees; P =0.005) or the anterior octant (50.7±11.7 degrees, preoperative: 45.8±8.9 degrees; P =0.012). CONCLUSIONS: The SDA and mSDA procedures produced similar postoperative changes, primarily in the superior and superior-posterior acetabular octants. Placing the graft more anteriorly did not increase anterior coverage in the mSDA, and only the PA increased coverage in the superior and superior-anterior acetabular octants.

Comparison of Outcomes in Pediatric and Adolescent Posterior Cruciate Ligament Injuries With and Without Meniscal Tears: Operative Versus Nonoperative Management.

Background: Despite the posterior cruciate ligament (PCL) being an essential stabilizer of the knee, there is a paucity of data regarding injury management in pediatric patients. Purpose/Hypothesis: The purpose of this study was to evaluate differences in outcomes after operative (OP) versus nonoperative (NOP) management of pediatric isolated (single-ligament) PCL tears. It was hypothesized that managing PCL tears operatively would lead to improved functional outcomes compared with NOP management, especially in the setting of an associated meniscal tear. Study Design: Cohort study; Level of evidence, 3. Methods: Pediatric patients with an isolated PCL injury between 2006 and 2020 were identified and grouped according to whether they had a concomitant meniscal tear (PCL+M) or no meniscal tear (PCL-M). These cohorts were further sorted into OP, NOP, and nonoperative converted to operative (NOP2OP) treatment cohorts. Outcome data collected included Lysholm score, current activity level, and whether the patient returned to sports after treatment. Results: A total of 48 patients (49 knees) met study inclusion criteria (31 male, 18 female; mean age at injury, 15.6 years; age range, 8.3-18.9 years). There were 37 knees in the PCL-M cohort (30 NOP, 2 NOP2OP, and 5 OP) and 12 knees in the PCL+M cohort (4 NOP, 4 NOP2OP, and 4 OP). The mean duration of follow-up was 6.2 years (range, 2.4-15.7 years). The mean Lysholm scores were not significantly different between the OP and NOP knees in either the PCL-M cohort (P = .582) or the PCL+M cohort (P = .570); however, the PCL-M cohort overall had significantly higher scores compared with the PCL+M cohort (92.7 ± 13.0 vs 82.8 ± 18.8, respectively; P = .019). Conclusion: The pediatric patients in this series had similar functional outcomes when managed operatively or nonoperatively for their single-ligament PCL tear. When considering concomitant meniscal injury, the results indicated that children with meniscal injury had a worse outcome than those without a meniscal injury. Shared decision-making with patients and their family should take these results into consideration.

Indocyanine green fluorescence guided resection of parathyroid adenoma of the carotid sheath: a case report and review of the literature.

Background: Ectopic parathyroid tissue can pose difficulties in diagnosis, management, and resection of adenomas in patients with hyperparathyroidism. The use of multimodal pre-operative imaging is recommended due to the diverse anatomic presentation of parathyroid adenomas and the potential presence of multiple adenomas. Resection failure still can occur, however, indocyanine green (ICG) fluorescence imaging is an intraoperative tool that has potential to help address this challenge. In the case which follows we demonstrate the use of ICG fluorescence imaging to assist in successful resection of a parathyroid adenoma located within the carotid sheath. Case Description: We present the case of a 75-year-old woman with primary hyperparathyroidism due to a parathyroid adenoma localized to the left carotid sheath, posterior to the carotid artery. Careful resection was aided by ICG fluorescence guidance allowing for complete resection and immediate postoperative restoration of normal parathyroid hormone and calcium levels. The patient had no peri-operative complications and had an unremarkable post-operative course. Conclusions: The anatomical heterogeneity of parathyroid gland adenomas within and around the carotid sheath presents a unique diagnostic and surgical scenario; however, the use of intra-operative ICG, as presented in this case, has important implications for endocrine surgeons and surgical trainees alike. This tool provides improved intra-operative identification of the parathyroid tissue allowing for safe resection, especially in cases involving critical anatomical structures.

A comparison of cone beam computed tomography, standard computed tomography and plain radiographs in the evaluation of medial epicondyle humerus fractures.

The ideal technique to measure medial epicondyle humerus fracture displacement minimizes radiation exposure while maximizing measurement accuracy and reliability. This study compares the radiation exposure and accuracy of displacement measurements of the four-view X-ray examination (XR), computed tomography (CT) and in-clinic cone-beam CT (CBCT). A cadaveric humerus underwent medial epicondyle osteotomy. The fragment was fixed to the humerus at clinically relevant displacements (6 to 18 mm). Dosimeters were placed around the distal humerus and simulating thyroid location. XR, CT and CBCT were performed at each displacement. Four pediatric orthopedists measured the maximum linear displacement on each XR and 3D reconstruction of the CT and CBCT images. Focal (elbow location) and thyroid radiation exposure was compared between modalities. Intra- and interclass correlation coefficients (ICC) for displacement measurements were determined. Mean focal radiation exposures for XR, CT and CBCT were 0.008, 2.061 and 0.478 rad, respectively (P = 0.001). Exposures 10 inches from the elbow for XR, CT and CBCT were 0.001, 0.066 and 0.010 rad, respectively (P = 0.006). At 12 inches, there was no significant difference in exposure between XR and CBCT ( P = 0.114). Intra- and interobserver reliabilities were excellent for all measures, except lateral x-ray. CBCT and CT had significantly less deviation from the actual displacement compared to XR ( P < 0.05). In-office CBCT of the elbow exposes patients to significantly less radiation than conventional CT. All X-ray images (except lateral), CT and CBCT had equal reliability in evaluating medial epicondyle fractures, which contrasts with previous evidence.