Determination of the ideal plate for medial femoral condyle fracture fixation: an anatomical fit and biomechanical study

BACKGROUND

The aim of this study is to determine the best plate to use as a substitute to fix a medial femoral condyle fracture.

MATERIALS AND METHODS

The first part is to measure the best fit between several anatomical plates including the Proximal Tibia Anterolateral Plate (PT AL LCP), the Proximal Tibia Medial Plate (PT M LCP), the Distal Tibia Medial Locking Plate (DT M LCP) and the Proximal Humerus (PHILOS) plate against 28 freshly embalmed cadaveric distal femurs. Measurements such as plate offset and number of screws in the condyle and shaft shall be obtained. The subsequent part is to determine the compressive force at which the plate fails. After creating an iatrogenic medial condyle fracture, the cadavers will be fixed with the two plates with the best anatomical fit and subjected to a compression force using a hydraulic press.

RESULTS

The PT AL LCP offered the best anatomical fit whereas the PHILOS plate offered the maximal number of screws inserted. The force required to create 2 mm of fracture displacement between the two is not statistically significant (LCP 889 N, PHILOS 947 N, p = 0.39). The PT AL LCP can withstand a larger fracture displacement than the PHILOS (LCP 24.4 mm, PHILOS 17.4 mm, p = 0.004).

DISCUSSION AND CONCLUSION

Both the PT AL LCP and the PHILOS remain good options in fixing a medial femoral condyle fracture. Between the two, we would recommend the PT AL LCP as the slightly superior option.

Shape variation and sex differences of the adult human mandible evaluated by geometric morphometrics

In cases of osseous defects, knowledge of the anatomy, and its age and sex-related variations, is essential for reconstruction of normal morphology. Here, we aimed at creating a 3D atlas of the human mandible in an adult sample using dense landmarking and geometric morphometrics. We segmented 50 male and 50 female mandibular surfaces from CBCT images (age range: 18.9-73.7 years). Nine fixed landmarks and 510 sliding semilandmarks were digitized on the mandibular surface, and then slid by minimizing bending energy against the average shape. Principal component analysis extracted the main patterns of shape variation. Sexes were compared with permutation tests and allometry was assessed by regressing on the log of the centroid size. Almost 49 percent of shape variation was described by the first three principal components. Shape variation was related to width, height and length proportions, variation of the angle between ramus and corpus, height of the coronoid process and inclination of the symphysis. Significant sex differences were detected, both in size and shape. Males were larger than females, had a higher ramus, more pronounced gonial angle, larger inter-gonial width, and more distinct antegonial notch. Accuracy of sexing based on the first two principal components in form space was 91 percent. The degree of edentulism was weakly related to mandibular shape. Age effects were not significant. The resulting atlas provides a dense description of mandibular form that can be used clinically as a guide for planning surgical reconstruction.

The Effects of Residual Femoral Deformity on Computed Contact Mechanics in Patients Treated With In Situ Fixation for Slipped Capital Femoral Epiphysis

OBJECTIVE

In situ fixation for treatment of slipped capital femoral epiphysis (SCFE) can stabilize the epiphysis and prevent further joint deformation but often leaves residual deformity that may adversely affect intra-articular contact mechanics. The purpose of this study was to investigate the relationship between residual deformity and contact mechanics in the post-SCFE hip.

METHODS

Patient-specific hip models were created for 19 patients with SCFE treated with in situ fixation. For each model, discrete element analysis was used to compute cumulative acetabular and femoral contact stress exposure during a walking gait cycle. Slip severity was evaluated for each patient using the two-dimensional Southwick angle and a novel three-dimensional (3D) assessment of multiplanar femoral deformity (3D slip angle).

RESULTS

Of the SCFE cases, 2/7 mild (Southwick angle ≤30 degrees) had peak cumulative femoral exposures equivalent to that of severe (Southwick angle ≥60 degrees) cases. Severe SCFE cases had higher peak ( P = 0.015) and mean ( P = 0.028) femoral contact stress exposure and lower cumulative femoral contact area ( P = 0.003) than mild (Southwick angle ≤30 degrees) SCFE cases. Mean femoral contact stress exposure was also higher in severe SCFE cases than in moderate SCFE cases ( P = 0.027). Acetabular and femoral contact mechanics metrics typically demonstrated stronger correlations with 3D slip angle than two-dimensional Southwick angle.

CONCLUSIONS

Increased slip severity adversely impacts intra-articular femoral contact mechanics. Contact mechanics metrics demonstrate higher correlations with 3D slip angle, indicating that this novel measurement may better describe global deformity and its relationship to intra-articular mechanics; however, the modest strength of these correlations may also imply that global impingement-generating deformity is not the primary factor driving contact mechanics in the post-SCFE hip.

CLINICAL RELEVANCE

Greater slip severity adversely impacts contact mechanics in the post-SCFE hip. However, focal regions of high contact stress were seen even in mild SCFE deformities, suggesting some type of deformity correction should be considered even for mild slips to alleviate secondary impingement, address focal incongruities, and reduce osteoarthritis development/progression.

Modified Radiographic Classification System for Congenital Thumb Duplication: An Analysis of 2,300 Thumbs in 2,108 Children

PURPOSE

The objectives of this study were to (1) evaluate the radiographic characteristics of children with congenital thumb duplication (CTD) seen in our institution between August 2015 and April 2021; (2) introduce a modified radiographic classification system (MCS) capable of including all cases of CTD based on their radiographic pathoanatomy; and (3) evaluate the inter- and intrarater reliability of the new classification system.

METHODS

We retrospectively reviewed 2,108 patients with 2,300 CTDs. The MCS is based on the Wassel-Flatt and Chung et al classification systems and includes specific subtypes from the Rotterdam and modified Wassel-Flatt classifications. The MCS is characterized by 4 groups according to the anatomical morphology of the duplication: A (joint), B (epiphysis), C (bone), and D (soft tissues). Each group includes 4 subtypes according to the location of the CTD, with subtypes 1-3 extending from the distal phalanx to the metacarpal or interphalangeal joints, then to the carpometacarpal joint, and with subtype 4 only including the triphalangia of the main thumb.

RESULTS

Among the 2,300 fingers, 360 (15.7%), 2 (0.1%), and 3 (0.1%) CTDs could not be classified according to the Wassel-Flatt, Chung et al, and Rotterdam classifications, respectively. According to the MCS, the 2 most common forms of CTD were A2 (680/2,300; 29.6%) and D2 (308/2,300; 13.4%). All cases could be classified according to this classification system. The MCS showed excellent intrarater (0.875) and interrater (0.851) reliability relative to the Wassel-Flatt (0.863 and 0.820, respectively), Chung et al (0.793 and 0.822, respectively), and Rotterdam (0.873 and 0.836, respectively) systems.

CONCLUSIONS

The MCS is a potential radiographic classification for CTD that enables the classification of all patients and has excellent inter- and intrarater reliability.

CLINICAL RELEVANCE

Existing classification systems do not allow classification of the full spectrum of CTD and are not always related to surgery, and some existing systems are complex, with many categories that are rarely encountered, or are difficult to use widely in clinical practice.

The effect of caponization on tibia bone histomorphometric properties of crossbred roosters

The negative effect of caponization on the structural, geometric and mechanical parameters of femur and tibia has been shown in a few studies. Nevertheless, its influence on tibia bone microarchitecture is still largely unknown. Therefore, this study aimed to assess the effect of castration on the microstructural parameters of the trabecular and compact bone of tibia bone in crossbred chickens. The experiment involved 96 roosters derived from crossing Yellowleg Partridge hens ([Formula: see text]-33) and Rhode Island Red cockerels (R-11) fattened until the 16th, 20th and 24th week of life. Animals were randomly divided into 2 groups of 48 each. Group I (control) consisted of intact roosters and group II (experimental) consisted of birds subjected to caponization at the 8th week of age. The castration surgery had no influence on some properties within compact bone such as osteon diameter On.Dm, osteon perimeter On.Pm, osteon area On.Ar, osteocyte lacunar number Ot.Lc.N, osteon bone area On.B.Ar, osteon wall thickness On.W.Th as well as thick-mature collagen content in all analyzed age groups of animals. Nevertheless, our results demonstrate that castration caused a decrease of Haversian canal area Hc.Ar, osteocyte lacunar area Ot.Lc.Ar and osteocyte lacunar porosity Ot.Lc.Po among the 16-week-old birds, decrease of Haversian canal perimeter Hc.Pm and increase of fraction of bone area On.B.Ar/On.Ar among 16- and 24-week-old individuals and also an increase of osteocyte lacunar density Ot.Lc.Dn in the osteons of the oldest roosters. Additionally, some microstructural parameters of trabecular bone show the negative effect of caponization. The youngest 16-week-old capons were characterized by thinnin the trabecular in the epiphysis part of tibia. Moreover, in the case of 24-week-old, there is an increase in the trabecular separation Tb.Sp with simultaneous decrease of trabecular number Tb.N compared to roosters, which may suggest the increase of the bone resorption among the oldest individuals. The increased bone turnover in the epiphysis part of the tibia bone also indicates changes in the collagen fibers distribution, where among 20-week-old animals there is a decrease in the content of immature thin collagen fibers with simultaneous increase in the content of mature thick collagen fibers. Furthermore, among the oldest 24-week-old individuals we can observe the increased thick-to-thin collagen ratio, which may be a sign of slowing down in bone formation.

Menarche at Amarna: Timing and the further implications

OBJECTIVE

This article examines skeletal development in non-elite individuals from Amarna to identify the age of menarche.

MATERIALS AND METHODS

The total sample (n = 267; 65 female, 39 male, 163 indeterminate) was examined for six variables indicative of the pubertal stage (mineralization of the mandibular canine root [n = 46], distal radius fusion [n = 227], proximal ulna fusion [n = 220], distal humerus fusion [n = 237], presence of the iliac crest epiphysis [n = 24], iliac crest fusion [n = 199]). Age and sex estimates are based on standard criteria for dental development and eruption, cranial and pelvic morphology, and post-cranial metric analysis.

RESULTS

The iliac crest epiphysis is rarely present before age 15 years. Beginning fusion of the distal radius and iliac crest suggests that by age 19, most individuals have entered the maturation phase, providing book ends for the timing of menarche. Variables elucidating the peak height velocity (proximal ulna and distal humerus fusion) narrow that span and suggest menarche is achieved around 15-17 years for most individuals, with a broader estimate of 14-19 years encompassing the known diversity in timing of menarche.

DISCUSSION

Menarche is commonly cited as an indicator of adult status. The observed later entrance into this life stage, and the associated reduced fertility, has broader implications for understanding of economic, social, biological, and demographic patterns observed at Amarna and among different social groups in the ancient city, as well as individual life histories.

A comparison of bone microarchitectural and transcriptomic changes in murine long bones in response to hindlimb unloading and aging

Age- and disuse-related bone loss both result in decreases in bone mineral density, cortical thickness, and trabecular thickness and connectivity. Disuse induces changes in the balance of bone formation and bone resorption like those seen with aging. There is a need to experimentally compare these two mechanisms at a structural and transcriptomic level to better understand how they may be similar or different. Bone microarchitecture and biomechanical properties were compared between 6- and 22-month-old C57BL/6 J male control mice and 6-month-old mice that were hindlimb unloaded (HLU) for 3 weeks. Epiphyseal trabecular bone was the compartment most affected by HLU and demonstrated an intermediate bone phenotype between age-matched controls and aged controls. RNA extracted from whole-bone marrow-flushed tibiae was sequenced and analyzed. Differential gene expression analysis additionally included 4-month-old male mice unloaded for 3 weeks compared to age-matched controls. Gene ontology analysis demonstrated that there were age-dependent differences in differentially expressed genes in young adult mice. Genes related to downregulation of cellular processes were most affected in 4-month-old mice after disuse whereas those related to mitochondrial function were most affected in 6-month-old mice. Cell-cycle transition was downregulated with aging. A publicly available dataset (GSE169292) from 3-month female C57BL/6 N mice unloaded for 7 days was included in ingenuity pathway analysis (IPA) with the other datasets. IPA was used to identify the leading canonical pathways and upstream regulators in each HLU age group. IPA identified "Senescence Pathway" as the second leading canonical pathway enriched in mice exposed to HLU. HLU induced activation of the senescence pathway in 3-month and 4-month-old mice but inhibited it in 6-month-old mice. In conclusion, we demonstrate that hindlimb unloading and aging initiate similar changes in bone microarchitecture and gene expression. However, aging is responsible for more significant transcriptome and tissue-level changes compared to hindlimb unloading.

Biomechanics of internal fixation in Hoffa fractures - A comparison of four different constructs

OBJECTIVE

Compare the biomechanical effectiveness of four different bone-implant constructs in preventing fracture displacement under axial loading.

METHODS

Twenty artificial femora had a standardized coronally oriented fracture of the lateral femoral condyle, representing a Hoffa fracture classified as a Letenneur type I. Four different fixation constructs were applied to the synthetic bones for biomechanical testing. The constructs consisted of a posterolateral (PL) buttressing locking plate in conjunction with two cannulated lag screws inserted from posterior to anterior (PA) - Group 1; Two cannulated screws inserted from anterior to posterior (AP) without plating- Group 2; A posterolateral (PL) buttressing locking plate in isolation - Group 3; and a combination of two lag screws from anterior to posterior (AP) in addition to a horizontal one-third tubular locking plate - Group 4. An axial load was applied to the fracture site with a constant displacement speed of 20 mm/min, and the test was interrupted when a secondary displacement was detected determining a fixation failure. We recorded the maximum applied force and the maximum fracture displacement values.

RESULTS

Group 1 demonstrated the highest overall bone-implant axial stiffness with the lowest secondary displacement under loading. Groups 3 and 4 showed equivalent mechanical behavior. Group 2 presented the lowest mechanical stiffness to axial loading. The combination of the one-third tubular locking plate with anterior-to-posterior lag screws (Group 4) resulted in 302 % increase in fixation stiffness when compared to anterior-to-posterior lag screws only (Group 2).

CONCLUSIONS

This study confirms the mechanical superiority of having a plate applied parallel to the main fracture plane in the setting of coronally oriented femoral condyle fractures. The addition of a horizontal plate, perpendicular to the main fracture plane, significantly increased the resistance to shearing forces at the fracture site when compared to constructs adopting just cannulated screws.

LEVEL OF EVIDENCE

Biomechanical study.

Positive outcome reporting in orthopaedic literature

Aims

Perthes' disease (PD) is a relatively rare syndrome of idiopathic osteonecrosis of the proximal femoral epiphysis. Treatment for Perthes' disease is controversial due to the many options available, with no clear superiority of one treatment over another. Despite having few evidence-based approaches, many patients with Perthes' disease are managed surgically. Positive outcome reporting, defined as reporting a study variable producing statistically significant positive (beneficial) results, is a phenomenon that can be considered a proxy for the strength of science. This study aims to conduct a systematic literature review with the hypothesis that positive outcome reporting is frequent in studies on the treatment of Perthes' disease.

Methods

We conducted a systematic review of all available abstracts associated with manuscripts in English or with English translation between January 2000 and December 2021, dealing with the treatment of Perthes' disease. Data collection included various study characteristics, surgical versus non-surgical management, treatment modality, mean follow-up time, analysis methods, and clinical recommendations.

Results

Our study included 130 manuscripts. Overall, 110 (85%) reported positive (beneficial) results, three (2%) reported negative results, and 17 (13%) reported no significant difference. Despite only 10/130 studies (8%) having a testable hypothesis, 71 (55%) recommended the use of their studied treatment methods for the patients, five (4%) made recommendations against the use of the studied treatment modality, and 54 (42%) did not make any recommendations.

Conclusion

The overall rate for positive outcomes among included manuscripts regarding different treatment methods for Perthes' disease (85%) is higher than the 74% positive outcome rate found among studies for other surgically treated disorders and significantly higher than most scientific literature. Despite the lack of testable hypotheses, most manuscripts recommended their studied treatment method as a successful option for managing patients solely based on the reporting of retrospective data.

Spontaneous improvement of bilateral clinodactyly of the little finger with trapezoidal phalanx: a case report with a 15-year follow-up

Clinodactyly can be produced by a longitudinal epiphyseal bracket that generates either a 'delta' or 'trapezoidal' phalanx. We present a case with a 15-year follow-up of bilateral clinodactyly of the little finger, to emphasize a 'wait-and-see' approach as self-remodelling of his phalanges occurred during growth.

Fixed and Relative Positioning of Scans for High Resolution Peripheral Quantitative Computed Tomography

INTRODUCTION

High resolution peripheral quantitative computed tomography (HR-pQCT) imaging protocol requires defining where to position the ∼1 cm thick scan along the bone length. Discrepancies between the use of two positioning methods, the relative and fixed offset, may be problematic in the comparison between studies and participants. This study investigated how bone landmarks scale linearly with length and how this scaling affects both positioning methods aimed at providing a consistent anatomical location for scan acquisition.

METHODS

Using CT images of the radius (N = 25) and tibia (N = 42), 10 anatomical landmarks were selected along the bone length. The location of these landmarks was converted to a percent length along the bone, and the variation in their location was evaluated across the dataset. The absolute location of the HR-pQCT scan position using both offset methods was identified for all bones and converted to a percent length position relative to the HR-pQCT reference line for comparison. A secondary analysis of the location of the scan region specifically within the metaphysis was explored at the tibia.

RESULTS

The location of landmarks deviated from a linear relationship across the dataset, with a range of 3.6 % at the radius sites, and 4.5 % at the tibia sites. The consequent variation of the position of the scan at the radius was 0.6 % and 0.3 %, and at the tibia 2.4 % and 0.5 %, for the fixed and relative offset, respectively. The position of the metaphyseal junction with the epiphysis relative to the scan position was poorly correlated to bone length, with R2 = 0.06 and 0.37, for the fixed and relative offset respectively.

CONCLUSION

The variation of the scan position by either method is negated by the intrinsic variation of the bone anatomy with respect both to total bone length as well as the metaphyseal region. Therefore, there is no clear benefit of either offset method. However, the lack of difference due to the inherent variation in the underlying anatomy implies that it is reasonable to compare studies even if they are using different positioning methods.

Corrective Osteotomy and Ligamentous Reconstruction in a Neglected Elbow Dislocation with Radial Neck Malunion: A Case Report

CASE

Neglected elbow dislocation and radial neck malunion frequently result in chronic pain, instability, and early arthrosis. These complications are best prevented by early treatment with open reduction, corrective osteotomy, and ligament reconstruction, followed by early supervised physiotherapy. We present a peculiar case with neglected complex elbow dislocation and radial head malunion. In this case, we performed an open reduction of the elbow joint and radial neck corrective osteotomy, medial collateral ligament, annular ligament reconstruction, and lateral collateral ligament repair.

CONCLUSION

Neglected complex elbow dislocations require reconstruction of both ligamentous and osseous structures to achieve a good functional outcome.

Tibial bone defect prediction based on preoperative artefact-reduced CT imaging is superior to standard radiograph assessment

PURPOSE

The purpose of this study was to evaluate the accuracy of preoperative CT-based Anderson Orthopaedic Research Institute (AORI)-grading and to correlate Computed tomography (CT)-based volumetric defect measurements with intraoperative AORI findings.

METHODS

99 patients undergoing revision total knee arthroplasty (rTKA) with preoperative CT-images were identified in an institutional revision registry. CT-image segmentation with 3D-Slicer Software was used to create 3D tibial bone defects which were then graded according to the AORI-classification. The AORI classification categorizes tibial defects into three types: Type I has healthy cortical and cancellous bone near the joint line, Type II involves metaphyseal bone loss affecting one or both condyles, and Type III indicates deficient metaphyseal bone with distal defects and potential damage to the patellar tendon and collateral ligament attachments. These 3D-CT gradings were compared to preoperative X-ray and intraoperative AORI grading. The Friedman test was used to investigate differences between AORI values of each measurement method. Volumetric 3D-bone defect measurements were used to investigate the relationship between AORI classification and volumetric defect size in the three anatomic zones of the tibia.

RESULTS

Substantial agreements between preoperative 3D-CT AORI and intraoperative AORI (kappa = 0.663; P < 0.01) and fair agreements between preoperative X-ray AORI and intraoperative AORI grading (kappa = 0.304; P < 0.01) were found. Moderate correlations between volume of remaining bone and intraoperative AORI grading were found in epiphysis (rS = - 0.529; P < 0.001), metaphysis (rS = - 0.557; P < 0.001) and diaphysis (rS = - 0.421; P < 0.001). Small volumetric differences between AORI I vs. AORI II defects and relatively large differences between AORI II and AORI III defects in each zone were detected.

CONCLUSION

Tibial bone defect prediction based on preoperative 3D-CT segmentation showed a substantial agreement with intraoperative findings and is superior to standard radiograph assessment. The relatively small difference in defect volume between AORI I, IIa and IIb suggests that updated CT-based classifications might hold benefits for the planning of rTKA.

LEVEL OF EVIDENCE

Retrospective Cohort Study; III.

Nonossifying Fibroma Involving Epiphysis of Long Bone-Case Report and Review of the Literature

Nonossifying fibroma (NOF) is a common benign bone neoplasm and is usually observed in the first 2 decades of life. Most NOFs occur in the metaphysis of long bones of the lower extremities and migrate toward the diaphysis during skeletal maturation. Epiphyseal involvement by NOF has been rarely reported, with only one case found in the English literature. The authors report the second case of NOF involving the epiphysis of a long bone, the proximal tibia of a 21-year-old woman. Clinicians and pathologists should be aware of the rare possibility of epiphyseal involvement of long bones by this condition. Pathologists should select appropriate immunohistochemistry markers to rule out alternative diagnoses.

Spatial heterogeneity of bone marrow endothelial cells unveils a distinct subtype in the epiphysis

Bone marrow endothelial cells (BMECs) play a key role in bone formation and haematopoiesis. Although recent studies uncovered the cellular taxonomy of stromal compartments in the bone marrow (BM), the complexity of BMECs is not fully characterized. In the present study, using single-cell RNA sequencing, we defined a spatial heterogeneity of BMECs and identified a capillary subtype, termed type S (secondary ossification) endothelial cells (ECs), exclusively existing in the epiphysis. Type S ECs possessed unique phenotypic characteristics in terms of structure, plasticity and gene expression profiles. Genetic experiments showed that type S ECs atypically contributed to the acquisition of bone strength by secreting type I collagen, the most abundant bone matrix component. Moreover, these cells formed a distinct reservoir for haematopoietic stem cells. These findings provide the landscape for the cellular architecture in the BM vasculature and underscore the importance of epiphyseal ECs during bone and haematopoietic development.

What it takes to have a high-grade pivot shift-focus on bony morphology

PURPOSE

Variations in femoral and tibial bony morphology have been associated with higher clinical grading and increased quantitative tibial translation, but not tibial acceleration, during the pivot shift test following anterior cruciate ligament (ACL) injury. The purpose of this study was to determine the impact of femoral and tibial bony morphology, including a measurement influenced by both parameters (the Lateral Tibiofemoral Articular Distance (LTAD)), on the degree of quantitative tibial acceleration during the pivot shift test and rates of future ACL injury.

METHODS

All patients who underwent primary ACL reconstruction from 2014 to 2019 by a senior orthopedic surgeon with available quantitative tibial acceleration data were retrospectively reviewed. All patients underwent a pivot shift examination under anesthesia with a triaxial accelerometer. Measurements of femoral and tibial bony morphology were performed by two fellowship-trained orthopedic surgeons using preoperative magnetic resonance imaging and lateral radiographs.

RESULTS

Fifty-one patients were included at a mean follow-up of 4.4 years. The mean quantitative tibial acceleration during the pivot shift was 13.8 m/s2 (range: 4.9-52.0 m/s2). A larger Posterior Condylar Offset Ratio (r = 0.30, p = 0.045), smaller medial-to-lateral width of the medial tibial plateau (r = - 0.29, p = 0.041), lateral tibial plateau (r = - 0.28, p = 0.042), and lateral femoral condyle (r = - 0.29, p = 0.037), and a decreased LTAD (r = - 0.53, p < 0.001) significantly correlated with increased tibial acceleration during the pivot shift. Linear regression analysis demonstrated an increase in tibial acceleration of 1.24 m/s2 for every 1 mm decrease in LTAD. Nine patients (17.6%) sustained ipsilateral graft rupture and 10 patients (19.6%) sustained contralateral ACL rupture. No morphologic measurements were associated with rates of future ACL injury.

CONCLUSION

Increased convexity and smaller bony morphology of the lateral femur and tibia were significantly associated with increased tibial acceleration during the pivot shift. Additionally, a measurement, termed the LTAD, was found to have the strongest association with increased tibial acceleration. Based on the results of this study, surgeons can utilize these measurements to preoperatively identify patients at risk of increased rotatory knee instability.

LEVEL OF EVIDENCE

Level IV.

Increased Medial Femoral Condyle Angle and Narrow Intercondylar Notch Are Associated With Medial Meniscus Posterior Root Tear

PURPOSE

To investigate the correlation between nontraumatic medial meniscus posterior root tear (MMPRT) and bone morphology of the knee with a particular emphasis on MMPR impingement.

METHODS

Magnetic resonance imaging (MRI) findings were examined between January 2018 and December 2020. MRI findings of patients with traumatic MMPRT, Kellgren Lawrence stage 3-4 arthropathy on radiographs, single- or multiple-ligament injuries and/or those who underwent treatment for these diseases, and surgery in and around the knee were excluded from the study. MRI measurements included medial femoral condylar angle (MFCA), intercondylar distance (ICD), and intercondylar notch width (ICNW), distal/posterior medial femoral condylar offset ratio, notch shape, medial tibial slope (MTS) angle, and medial proximal tibial angle (MPTA) measurements and spur presence and were compared between groups. All measurements were performed by two board-certified orthopedic surgeons on a best agreement basis.

RESULTS

MRI examinations of patients aged 40-60 were analyzed. MRI findings were divided into two groups: the study group of MRI findings of patients with MMPRT (n = 100) and the control group of MRI findings of patients without MMPRT (n = 100). MFCA was found to be significantly higher in the study group (mean: 46.5 ± 3.58) than in the control group (mean: 40.04 ± 4.61) (P < .001). In the study group, the ICD (study group mean: 76.26 ± 4.89; control group mean: 78.18 ± 6.1) was significantly narrower (P = .018), and the ICNW (study group mean: 17.19 ± 2.23; control group mean: 20.48 ± 2.13) was significantly shorter (P < .001). The ICNW/ICD ratio was significantly lower in patients in the study group (0.22 ± 0.02) than in the control group (0.25 ± 0.02) (P < .001). Bone spurs were present in 84% of the study group and only in 28% of those in the control group. In the study group, the most common notch type was A-type with 78%, while the least common was the U-type notch with 10%. However, in the control group, the most common notch type was A-type with 43%, and the least common was the W-type notch with 22%. The distal/posterior medial femoral condylar offset ratio was statistically lower in the study group (0.72 ± 0.07) than in the control group 0.78 ± 0.07) (P < .001). No significant intergroup differences were found in MTS (study group mean: 7.51 ±2.59; control group mean: 7.83 ± 2.57) (P = .390) and MPTA (study group mean: 86.92 ±2.15; control group mean: 87.48 ±1.8) measurements (P = .67).

CONCLUSIONS

Increased medial femoral condylar angle, low distal/posterior femoral offset ratio, narrow intercondylar distance and intercondylar notch width, A-type notch shape, and spur presence are associated with MMPRT.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Comparison of three radiographic assessment methods for detecting slipped capital femoral epiphyses in cats: Klein's line, modified Klein's line and the S-sign

OBJECTIVES

The aim of the present study was to investigate whether diagnostic assessment methods used on radiographs in humans with slipped capital femoral epiphysis (SCFE) can be used in cats.

METHODS

The ventrodorsal (VD) extended-leg and VD frog-leg pelvic radiographs of 20 cats with SCFE without fully displaced femoral capital epiphyses (FCE), eight cats with fully displaced FCE and five control cats with normal pelvic anatomy were assessed by five observers on two separate occasions 3 months apart. The Klein's line and modified Klein's line were assessed on each VD extended-leg radiograph, and the S-sign was assessed on each VD extended-leg and VD frog-leg radiograph.

RESULTS

Excluding cases of fully displaced FCE, the S-sign on the VD frog-leg radiographs more accurately diagnosed SCFE than the S-sign on the VD extended-leg radiographs and the Klein's line (92.4% vs 88.8% vs 60.6%, respectively), and had the greatest sensitivity (93.9% vs 79.2% vs 30.6%, respectively). The S-sign on the VD extended-leg radiographs had greater specificity than the Klein's line and S-sign on the VD frog-leg radiographs (99.2% vs 97.9% vs 90.9%, respectively). The modified Klein's line detected SCFE in 40.2% of cases that were negative for the Klein's line.

CONCLUSIONS AND RELEVANCE

The S-sign in both VD extended-leg and VD frog-leg views successfully detected SCFE in cats and can be used to increase early diagnosis and treatment in cats with SCFE that have only subtle radiographic changes.

Combined Lateral Closing and Medial Opening-Wedge Proximal Humerus Osteotomy in an Adolescent with Extreme Varus Deformity: A Case Report

CASE

This report describes the case of an athletic 12-year-old boy who presented with a 64° left proximal humeral varus angulation deformity and physeal bar secondary to multiple operations for a proximal humeral metaphyseal cystic lesion and pathologic fracture. Using a combined lateral closing and medial opening-wedge osteotomy, a 68° valgus correction was achieved with excellent clinical and functional outcomes at 16-month follow-up. Forward flexion increased from 120 to 170° preoperatively to postoperatively while abduction improved from 110° preoperatively to 170° postoperatively.

CONCLUSION

A combined lateral closing and medial opening-wedge osteotomy of the proximal humerus can successfully treat cases of extreme proximal humerus varus in the growing shoulder where unilateral or dome osteotomies are not suitable.

Future distribution of the epiphytic leafless orchid (Dendrophylax lindenii), its pollinators and phorophytes evaluated using niche modelling and three different climate change projections

The identification of future refugia for endangered species from the effects of global warming is crucial for improving their conservation. Because climate-driven shifts in ranges and local extinctions can result in a spatial mismatch with their symbiotic organisms, however, it is important to incorporate in niche modelling the ecological partners of the species studied. The aim of this study was to evaluate the effect of climate change on the distribution of suitable niches for the ghost orchid (Dendrophylax lindenii) and its phorophytes and pollinators. Thus, its five species of host trees and three pollen vectors were included in the analysis. Climatic preferences of all the species studied were evaluated. The modelling was based on three different climate change projections and four Shared Socio-economic Pathway trajectories. All the species analysed are characterized by narrow temperature tolerances, which with global warming are likely to result in local extinctions and range shifts. D. lindenii is likely to be subjected to a significant loss of suitable niches, but within a reduced geographical range, both host trees and pollen vectors will be available in the future. Future conservation of this orchid should focus on areas that are likely be suitable for it and its ecological partners.

Effects of joint loading on the development of capital femoral epiphysis morphology

INTRODUCTION

The deleterious influence of increased mechanical forces on capital femoral epiphysis development is well established; however, the growth of the physis in the absence of such forces remains unclear. The hips of non-ambulatory cerebral palsy (CP) patients provide a weight-restricted (partial weightbearing) model which can elucidate the influence of decreased mechanical forces on the development of physis morphology, including features related to development of slipped capital femoral epiphysis (SCFE). Here we used 3D image analysis to compare the physis morphology of children with non-ambulatory CP, as a model for abnormal hip loading, with age-matched native hips.

MATERIALS AND METHODS

CT images of 98 non-ambulatory CP hips (8-15 years) and 80 age-matched native control hips were used to measure height, width, and length of the tubercle, depth, width, and length of the metaphyseal fossa, and cupping height across different epiphyseal regions. The impact of age on morphology was assessed using Pearson correlations. Mixed linear model was used to compare the quantified morphological features between partial weightbearing hips and full weightbearing controls.

RESULTS

In partial weightbearing hips, tubercle height and length along with fossa depth and length significantly decreased with age, while peripheral cupping height increased with age (r > 0.2, P < 0.04). Compared to normally loaded (full weightbearing) hips and across all age groups, partially weightbearing hips' epiphyseal tubercle height and length were smaller (P < .05), metaphyseal fossa depth was larger (P < .01), and posterior, inferior, and anterior peripheral cupping heights were smaller (P < .01).

CONCLUSIONS

Smaller epiphyseal tubercle and peripheral cupping with greater metaphyseal fossa size in partial weightbearing hips suggests that the growing capital femoral epiphysis requires mechanical stimulus to adequately develop epiphyseal stabilizers. Deposit low prevalence and relevance of SCFE in CP, these findings highlight both the role of normal joint loading in proper physis development and how chronic abnormal loading may contribute to various pathomorphological changes of the proximal femur (i.e., capital femoral epiphysis).

Assessing lateral femoral condyle cartilage prior to medial UKA: MRI vs. Valgus stress radiograph

BACKGROUND

The cartilage quality of the lateral compartment needs to be clarified prior to medial unicompartmental knee arthroplasty (UKA). Valgus stress radiograph has been recommended as the preferred tool. Some studies also show that magnetic resonance imaging (MRI) has a higher diagnostic value. So, we conducted this study to compare whether valgus stress radiographic lateral joint space width (LJSW) and MRI grading can accurately reflect cartilage quality and its screening value for UKA-suitable patients.

METHODS

One hundred and thirty eight knees proposed for UKA were enrolled prospectively. Valgus stress radiograph was taken to measure LJSW. LJSW > 4 mm was considered normal and suitable for UKA. For weight-bearing area cartilage of lateral femoral condyle, Recht grade was assessed by MRI preoperatively. Recht grades ≤ 2 were treated as non-high-grade injuries while Recht grades > 2 were treated as high-grade injuries. Outerbridge grade was the gold standard and was assessed intraoperatively. Patients with Outerbridge grades 0-2 (non-high-grade injuries) underwent UKA, and patients with Outerbridge grades 3-4 (high-grade injuries) underwent total knee arthroplasty (TKA). The diagnostic parameters of valgus stress radiograph and MRI for the selection of UKA candidates were calculated, and receiver operating characteristic curves were drawn. P < 0.05 was considered significant.

RESULTS

Of 138 knees, 120 underwent UKAs, and 18 underwent TKAs. In terms of selecting UKA candidates, the sensitivity was close between MRI (95.0%) and valgus stress radiograph (96.7%), and the specificity, accuracy, positive predictive value and negative predictive value of MRI (94.4%, 94.9%, 99.1%, 73.9%, respectively) were higher than that of valgus stress radiograph (5.9%, 85.5%, 88.0%, 20.0%, respectively). The difference in area under the curve (AUC) between MRI (0.950) and LJSW (0.602) was significant (P = 0.001).

CONCLUSION

Compared with valgus stress radiograph, MRI has excellent evaluation value in diagnosing lateral weight-bearing cartilage injuries and can be used as a reliable tool for selecting suitable UKA patients.

The effect of oral hydroxychloroquine on chondral defect: An experimental study

OBJECTIVES

This study aims to evaluate the time- and dose-dependent effects of oral hydroxychloroquine (HCQ) on focal full-thickness knee chondral defect healing in a rabbit model.

MATERIALS AND METHODS

Cartilage defects of 4x4 mm2 were created on both medial femoral condyles of 24 New Zealand rabbits. The rabbits were divided into six groups (A-F) according to HCQ administration and sacrifice time: A (three-week control) and B (six-week control) received no additional interventions; C (20 mg/kg HCQ, three weeks); D (20 mg/kg HCQ, six weeks); E (40 mg/kg HCQ, three weeks); and F (40 mg/kg HCQ, six weeks). Osteochondral specimens were evaluated macroscopically, histologically, and immunohistochemically. The terminal deoxynucleotidyl-transferase (TdT)-mediated dUTP nick end labeling (TUNEL) method was used to detect apoptotic cells.

RESULTS

The International Cartilage Repair Society (ICRS) scores were significantly higher in the experimental groups than in the controls (p<0.001). The Wakitani scores in Group D showed a significant improvement compared to those in Group B (p<0.01). The 20 mg/kg HCQ treatment groups showed better recovery than the controls (p<0.01). High-dose HCQ (40 mg/kg) treatment significantly reduced the intensity of collagen type 2 immunoreactivity compared to that in the groups receiving 20 mg/kg of HCQ (p<0.01). Collagen type 2 expression in Group F was significantly lower than that in Group D (p<0.01). There were more TUNEL-positive cells in the repair sites of Groups E and F than in the lower-dose experimental groups and untreated experimental groups (p<0.001).

CONCLUSION

A low dose of HCQ improved cartilage repair, while higher doses of HCQ exerted a negative effect on cartilage regeneration in rabbits. In the presence of defective cartilage, the use of HCQ at an appropriate dose and time is important for cartilage health.

Review of minimally invasive surgical procedures for assessment and treatment of medial coronoid process disease

OBJECTIVE

To summarize the current peer-reviewed publications on minimally invasive surgery (MIS) for medial coronoid process disease (MCPD) in dogs.

STUDY DESIGN

Invited review.

METHODS

Pubmed, CAB Abstracts and Scopus databases were utilized for literature review (1990-2023).

RESULTS

More than 60 papers have been published that involve MIS evaluation or treatment of MCPD. Six prospective trials incorporated quantitative gait analysis evaluating outcome following MCPD debridement, of which three included a control group. Whilst case numbers were limited, all studies employing a control group failed to demonstrate superiority of surgery over nonsurgical management. Of three studies employing gait analysis and no control group, all documented some improvement in function compared to pretreatment lameness. Multiple studies document progression of osteoarthritis in dogs following MCPD debridement although this may not be synonymous with worsened function. Subtotal coronoid osteotomy (SCO) is described as an alternative to MCP fragment removal, although the long-term biomechanical consequences are currently unclear and quantitative data on the efficacy of this treatment in isolation for MCPD is awaited.

CONCLUSION

Arthroscopy of the canine elbow joint is a safe means by which to evaluate MCP pathology. Quantitative longitudinal analysis of outcome following minimally invasive surgery for MCPD is required. Correlation with clearly defined subclassification inclusion criteria such as age, incongruity and the precise arthroscopic findings in each case are required to more accurately differentiate any superiority of surgery over nonsurgical management for this disease.

Epidemiology and risk factors for premature physeal closure in distal femur fractures

BACKGROUND AND PURPOSE

Premature physeal closure (PPC) is a common and concerning complication to distal femoral fractures as the distal growth plate accounts for 70% of the growth of the femur. The literature is not unanimous in determining the risk factors of PPC, and the epidemiological characterization of these fractures is limited. Our aim was to calculate the population-based incidence and investigate risk factors for PPC in these fractures.

PATIENTS AND METHODS

In this register-based study, between 2014 and 2021, 70 children with distal femoral physeal fractures presented to our hospital. Demographic data, and fracture- and treatment-related details were collected using the Kids' Fracture Tool. A directed acyclic graph (DAG) was constructed to determine confounding factors used in the risk analysis.

RESULTS

Physeal fractures of the distal femur occurred with an annual incidence of 6/105 children, and a resulting PPC occurred in 16/70 (23%) with an annual incidence of 1.3/105 children. In multivariable analysis, dislocation exceeding 10 mm was a risk factor for PPC (OR 6.3, CI 1.4-22).

CONCLUSION

One-fourth of distal femoral physeal fractures developed PPC. Greater dislocation and higher injury energy were significant risk factors, whereas choice of fracture treatment was not an independent risk factor. All patients with PPC belonged in the age group 11-16 years.

Fungal Osteomyelitis of the Proximal Tibial Epiphysis and Septic Arthritis Secondary to an Open Wound: A Case Report

CASE

A 9-year-old boy presented with a painful, swollen knee. He had a wound on the knee 2 months ago after a fall in contaminated water. At another hospital, this was treated with debridement twice, and the patient received several antibiotics. Imaging showed septic arthritis and epiphyseal osteomyelitis involving the proximal medial tibia. Surgical debridement and joint washout were performed. Fungal cultures grew Scedosporium boydii. Antifungal treatment with voriconazole was given. At a 5-year follow-up, we noticed favorable outcomes without any complications.

CONCLUSIONS

Fungal osteomyelitis because of direct inoculation should be considered a rare differential diagnosis while treating epiphyseal osteomyelitis.

Brachial Plexus Birth Injury due to Proximal Humeral Physeal Separation: A Case Report

CASE

A 9-day-old male neonate presented with swelling over his left shoulder and reduced movements of the left upper extremity since birth. Radiographs raised a suspicion of a shoulder dislocation. Ultrasonography confirmed the diagnosis of proximal humeral physeal separation. Magnetic resonance imaging (MRI) revealed edema of the infraclavicular part of the brachial plexus. Conservative management was followed, and the injury remodeled completely at 2 years.

CONCLUSION

Neonatal proximal humeral physeal separation poses a diagnostic challenge. Ultrasonography is helpful for diagnosis. MRI is indicated when concurrent brachial plexus birth injury is suspected. Conservative management yields good outcome in the absence of entrapped nerves and tendons.

Triceps Rupture After Olecranon Fixation with Proximal Ulna Plate and Suture Augmentation: A Case Report

CASE

Olecranon fractures treated with proximal ulna plate fixation and repairing the triceps with suture augmentation to the plate decrease the risk of "olecranon escape," but may lead to failure through triceps rupture. In this case report, a rare complication of triceps rupture occurred, and the patient underwent triceps repair.

CONCLUSION

When fixing olecranon fractures, surgeons should minimize triceps dissection for hardware placement. If subjected to significant force, a surgical insult to the tendon footprint for a better plate contact on the bone and the presence of suture augmentation may change the construct failure mechanism and result in triceps rupture as opposed to fracture redisplacement.

Bone Mineral Loss at the Distal Femur and Proximal Tibia Following Spinal Cord Injury in Men and Women

PURPOSE

Spinal cord injury (SCI) causes rapid bone loss and increases risk of fragility fractures in the lower extremities. The majority of individuals with SCI are men, and few studies have investigated sex as a biological variable in SCI-induced osteoporosis. This cross-sectional study aimed to quantify sex-specific differences in bone mineral following SCI.

METHODS

Quantitative computed tomography (QCT) scans of the distal femur and proximal tibia were obtained at baseline of one of four clinical trials enrolling people who sustained SCI 1 month to 50 years prior to recruitment. Bone volume (BV), bone mineral content (BMC), bone mineral density (BMD), and bending strength index (BSI) were quantified in the integral, trabecular, and cortical bone in the epiphysis, metaphysis and diaphysis. Scans from 106 men and 31 women were analyzed to measure sex-specific effects on bone loss over time post-SCI.

RESULTS

BMC and BSI declined exponentially as a function of time post-SCI and were best described by separate decay curves for men and women. Women had BV, BMC, and BSI at 58-77% that of men in the acute and plateau phases, with both sexes showing similar rates of loss as a function of time post-SCI. Trabecular BMD was best described as an exponential decay versus time post-SCI, with no sex-specific differences.

CONCLUSIONS

Due to consistently lower BV, BMC, and BSI, women may be more susceptible to fractures after SCI than men.

Modified ulnar lengthening for correction of the Masada type 2 forearm deformity in hereditary multiple exostosis

Few articles have reported on the treatment of Masada type 2 forearm deformities in hereditary multiple exostosis, possibly because of the high redislocation rate and other complications. This study precisely declares the use of modified ulnar lengthening by an Ilizarov external fixation with tumour excision for the treatment of Masada type 2 forearm deformities. 20 children with Masada type 2 forearm deformities were admitted for surgical treatment at our hospital from February 2014 to February 2021. There were 13 girls and 7 boys, ranging in age from 3.5 to 15 years (mean: 9 years) at the time of operation. We removed the prominent osteochondromas of the distal ulna and the proximal radius, positioned a classic Ilizarov external fixator on the forearm and then performed ulnar transverse one-third proximal diaphyseal subperiosteal osteotomy. We adopted modified ulnar lengthening postoperatively. The effects of surgical correction of deformity and functional improvement of the limb were assessed via regular follow-up and X-ray. The patients were followed up for 36 months, and the ulna was lengthened 26.99 mm on average; all radial heads remained relocated. The radiographic evaluations, including relative ulnar shortening, radial articular angle, and carpal slip, were improved. The functions of the elbow and forearm were all improved after surgery. Modified ulnar lengthening by an Ilizarov external fixation with tumour excision for the treatment of Masada type 2 forearm deformities in hereditary multiple exostoses has been proven to be an effective and reliable technique in the early stage.

Posterior cruciate ligament rupture and all-epiphyseal repair with suture tape augmentation in a 5-year-old girl: a case report and review of the literature

INTRODUCTION

Only a few case reports regarding pediatric posterior cruciate ligament (PCL) ruptures without bone avulsion exist in the literature. The present study aims to share our experience in the diagnosis, treatment, and prognosis of a child with a proximal PCL tear.

MATERIALS AND METHODS

This article reports a 5-year-old female diagnosed with a proximal PCL tear. The ruptured PCL was repaired with an all-epiphyseal suture tape augmentation (STA) without evidence of growth plate violation.

RESULTS

The suture tape was removed under arthroscopy and revealed the PCL was re-attached at 12 months after the first surgery. And at the time of this report, 36 months after surgery, she was doing well without any problems and with negative posterior drawer test.

CONCLUSIONS

Pediatric PCL tear without bone avulsion is rare. However, the torn PCL was noticed healed based on an arthroscopic second-look.

Regional modular responses in different bone compartments to the anabolic effect of PTH (1-34) and axial loading in mice

Beneficial effects of intermittent parathyroid hormone (PTH) on bone mass and architecture are described to either simply add to, or to synergise with those of mechanical loading. We evaluate whether interaction with in vivo loading is reinforced by PTH dosing regimen and exhibits compartment-specific sensitivities. Female 12-week-old C57Bl6 mice received daily (7/7) or interrupted 5 day/week (5/7) PTH for 3 weeks (two vehicle groups). All mice had six loading episodes (12N) applied to right tibia (left, non-loaded) for the last 2 weeks. Micro-CT scans were used to evaluate mass and architecture in almost the entire cortical and proximal trabecular regions. Epiphyseal cortical, trabecular and marrow space volumes, and bony growth-plate bridge incidence were evaluated. Statistical analyses employed a linear mixed-effects model at each percentile and 2-way ANOVA with post-hoc test for epiphyses and bridging. We found that daily PTH enhances cortical mass and modifies shape along almost the entire tibia and that these effects are partly mitigated by brief interruption in treatment. Mechanical loading alone augments cortical mass and modifies shape but only in a region proximal to the tibiofibular junction. The effect of combining load and daily PTH dosing is solely additive for cortical bone mass with no significant load: PTH interaction, but exhibits clear synergy with interrupted PTH treatment. Daily, not interrupted PTH stimulates trabecular bone gains, yet load:PTH interaction is present at limited regions with both daily and interrupted treatment. PTH treatment, but not loading, modifies epiphyseal bone but, in contrast, only loading modifies bridge number and areal density. Our findings demonstrate impressive local effects on tibial mass and shape of combined loading and PTH that are sensitive to dosing regimen and exert their effects modularly. These findings emphasise a need to clarify PTH dosing regimens and that advantages could be accrued by aligning treatment accordingly to patient requirements and life-style.

Evaluation of the knee joint morphology associated with a complete discoid lateral meniscus, as a function of skeletal maturity, using magnetic resonance imaging

INTRODUCTION

A discoid lateral meniscus (DLM) is associated with increased risk for meniscal tears and progression of knee joint osteoarthritis. Our aim was to differentiate knee joint morphology between patients with and without a DLM, as a function of skeletal maturity, using magnetic (MR) imaging.

MATERIALS AND METHODS

This was a retrospective analysis of MR images of the knee for 110 patients, 6-49 years of age. Of these, 62 were in the open physis group (38 with a DLM) and 48 in the closed physis group (23 with a DLM). The following morphological parameters were measured: anterior obliquity of the lateral tibial plateau (AOLTP), posterior obliquity of the lateral tibial plateau (POLTP), the lowest point of the lateral femoral condyle (LPLFC), and the posterior lateral condylar angle (PLCA).

RESULTS

Regardless of skeletal maturity, a DLM was associated with a greater inclination of the POLTP, lateralization of the LPLFC, and smaller PLCA (p < 0.001 for all compared to that of the control group). In the DLM group, the inclination of the AOLTP and the POLTP were significantly smaller (p < 0.001) and the LPLFC was more lateral (p < 0.001) in the closed physis group than in the open physis group. In the control group, the inclination of the POLTP was larger (p < 0.001) and the PLCA smaller (p = 0.019) in the open than in the closed physis group.

CONCLUSIONS

We identified a characteristic knee morphology among patients with a complete DLM using MR imaging, which was observed before physeal closure and persisted after skeletal maturity was attained. We also noted lateralization of the LPLFC in the presence of a DLM, with an increase in lateralization with skeletal maturation.

LEVEL OF EVIDENCE

Case-control study, III.

Three-dimensional printing designed customized plate in the treatment of coronal fracture of distal humerus in teenager: A case report

RATIONALE

Because of the complicated anatomy and considerable change in size and morphology with age in teenagers, the appropriate internal fixator of coronal shear fracture of distal humerus is difficult to choose, and therefore, the fixation of this kind of fracture is difficult and controversial. Furthermore, distal humeral fractures in teenagers often involve the epiphysis, the rigid fixation of fracture and the simultaneous minimally invasive and protection of the epiphysis are contradictory. Coronal shear fractures of the distal humerus in teenagers are great challenge for orthopedic surgeons. Three-dimensional (3D) printing designed customized plate in the treatment of coronal fracture of distal humerus in teenager is a potential satisfactory choice in the treatment of the complex fractures.

PATIENT CONCERNS

A teenager suffered from an elbow joint injury due to a fall while running, resulting in pain, swelling and limited movement of the elbow joint. The epiphyseal has not closed in this patient, conventional surgical procedures have great traumatic and invasive, and to some extent affect bone growth in children.

DIAGNOSES

Coronal shear fracture of right distal humerus according to computed tomography scan.

INTERVENTIONS

We used 3D printing technology to design an internal fixation device for this patient, which was to treat the distal humeral coronal shear fracture in a teenager via an anterior approach to the elbow joint, and finally the child was instructed to perform immediate postoperative functional exercises and rehabilitation.

OUTCOMES

Radiographic reexamination performed 1 day and 2 month after the operation showed that the internal fixation was in good position, no fracture displacement. the patient was instructed to perform active flexion and extension internal and external rotation of the right elbow 6 weeks postoperatively. The Mayo elbow function score was excellent 5 months postoperatively. The range of motion of the elbow was (15°-130°).

LESSONS

The treatment of coronal shear fractures of the distal humerus in teenager is controversial at present. This report 3D printing technology designed customized plate in treatment of such fractures showed satisfactory results, which provides a feasible method for the treatment of fractures without suitable internal fixation devices in the future.

Comparison of Different Fixation Confi gurations in Different Types of High Pediatric Supracondylar Humerus Fractures: a Finite Element Analysis

PURPOSE OF THE STUDY

The purpose of this study is to compare the stability of different fi xation methods in high pediatric supracondylar humerus fractures with a fi nite element analysis method. MATERIAL AND METHODS Transverse, lateral oblique, and medial oblique fracture models were created in a ten years old boy's distal humerus. Eight different fi xation methods were applied to each fracture model. Displacement of the fracture models was measured under the translational and torsional forces. RESULTS In the transverse fracture model; the 6th method provided the best stability in internal rotation, external rotation, and extension loading. In varus 7th method, valgus 8th, and fl exion the 5th and 2nd methods had the best stability. In the lateral oblique fracture model; the 7th method had the best stability in all loading directions except fl exion and the 6th method had the best stability in fl exion and had acceptable values in all other directions except valgus and external rotation. In the medial oblique fracture model; the 6th method had the best stability in all directions except varus. 3rd method was the best fi xation type against varus and the second stable fi xation type in all other directions. CONCLUSIONS Combining lateral antegrade with lateral retrograde wire and lateral condylomedullary wire provides strong stability in the lateral oblique fracture. Two condylomedullary Kirchner wires and one antegrade lateral wire results in a strong stability in the medial oblique fracture. Medial-lateral condylomedullary and lateral antegrade wires provided the best stability against varus in transverse and lateral oblique fractures.

KEY WORDS

high pediatric supracondylar humerus fracture, percutaneous fi xation method, metaphyseal-diaphyseal junction, fi nite element analysis.

Subchondral bone structure and synovial fluid metabolism are altered in injured and contralateral limbs 7 days after non-invasive joint injury in skeletally-mature C57BL/6 mice

OBJECTIVE

Post-traumatic osteoarthritis (PTOA) commonly develops after ACL injury, but early changes to the joint soon after injury are insufficiently understood. The objectives of this study were (1) evaluate the response of subchondral bone tissue modulus to joint injury and (2) identify which bone structural, material, and metabolic outcomes are local (i.e., injured joint only) or systemic (i.e., injured and contralateral-to-injured).

DESIGN

Female C57Bl∖6N mice (19 weeks at injury) underwent tibial compression overload to simulate ACL injury (n = 8) or a small pre-load (n = 8). Synovial fluid was harvested at euthanasia 7 days later for metabolomic profiling. Bone outcomes included epiphyseal and SCB microarchitecture, SCB nanoindentation modulus, SCB formation rate, and osteoclast number density.

RESULTS

Injury decreased epiphyseal bone volume fraction ([-5.29, -1.38%], P = 0.0016) and decreased SCB thickness for injured vs sham-injured limbs ([2.2, 31.4 μm], P = 0.017)). Epiphyseal bone loss commonly occurred for contralateral-to-injured limbs. There was not sufficient evidence to conclude that SCB modulus changes with injury. Metabolomic analyses revealed dysregulated synovial fluid metabolism with joint injury but that many metabolic pathways are shared between injured and contralateral-to-injured limbs.

CONCLUSION

This study demonstrates rapid changes to bone structure and synovial fluid metabolism after injury with the potential for influencing the progression to PTOA. These changes are often evidenced in the contralateral-to-injured limb, indicating that systemic musculoskeletal responses to joint injury should not be overlooked.

Denosumab treatment is associated with decreased cortical porosity and increased bone density and strength at the proximal humerus of ovariectomized cynomolgus monkeys

Upper extremity fractures, including those at the humerus, are common among women with postmenopausal osteoporosis. Denosumab was shown to reduce humeral fractures in this population; however, no clinical or preclinical studies have quantified the effects of denosumab on humerus bone mineral density or bone microarchitecture changes. This study used micro-computed tomography (μCT) and computed tomography (CT), alongside image-based finite element (FE) models derived from both modalities, to quantify the effects of denosomab (DMAb) and alendronate (ALN) on humeral bone from acutely ovariectomized (OVX) cynomolgus monkeys. Animals were treated with 12 monthly injections of s.c. vehicle (VEH; n = 10), s.c. denosumab (DMAb; 25 mg/kg, n = 9), or i.v. alendronate (ALN; 50 μg/kg, n = 10). Two more groups received 6 months of VEH followed by 6 months of DMAb (VEH-DMAb; n = 7) or 6 months of ALN followed by 6 months of DMAb (ALN-DMAb; n = 9). After treatment, humeri were harvested and μCT was used to quantify tissue mineral density, trabecular morphology, and cortical porosity at the humeral head. Clinical CT imaging was also used to quantify trabecular and cortical bone mineral density (BMD) at the ultra-proximal, proximal, 1/5 proximal and midshaft of the bone. Finally, μCT-based FE models in compression, and CT-based FE models in compression, torsion, and bending, were developed to estimate differences in strength. Compared to VEH, groups that received DMAb at any time demonstrated lower cortical porosity and/or higher tissue mineral density via μCT; no effects on trabecular morphology were observed. FE estimated strength based on μCT was higher after 12-months DMAb (p = 0.020) and ALN-DMAb (p = 0.024) vs. VEH; respectively, FE predicted mean (SD) strength was 4649.88 (710.58) N, and 4621.10 (1050.16) N vs. 3309.4 (876.09) N. All antiresorptive treatments were associated with higher cortical BMD via CT at the 1/5 proximal and midshaft of the humerus; however, no differences in CT-based FE predicted strength were observed. Overall, these results help to explain the observed reductions in humeral fracture rate following DMAb treatment in women with postmenopausal osteoporosis.

Cranial Base Synchondrosis Lacks PTHrP-Expressing Column-Forming Chondrocytes

The cranial base contains a special type of growth plate termed the synchondrosis, which functions as the growth center of the skull. The synchondrosis is composed of bidirectional opposite-facing layers of resting, proliferating, and hypertrophic chondrocytes, and lacks the secondary ossification center. In long bones, the resting zone of the epiphyseal growth plate houses a population of parathyroid hormone-related protein (PTHrP)-expressing chondrocytes that contribute to the formation of columnar chondrocytes. Whether PTHrP⁺ chondrocytes in the synchondrosis possess similar functions remains undefined. Using Pthrp-mCherry knock-in mice, we found that PTHrP⁺ chondrocytes predominantly occupied the lateral wedge-shaped area of the synchondrosis, unlike those in the femoral growth plate that reside in the resting zone within the epiphysis. In vivo cell-lineage analyses using a tamoxifen-inducible Pthrp-creER line revealed that PTHrP⁺ chondrocytes failed to establish columnar chondrocytes in the synchondrosis. Therefore, PTHrP⁺ chondrocytes in the synchondrosis do not possess column-forming capabilities, unlike those in the resting zone of the long bone growth plate. These findings support the importance of the secondary ossification center within the long bone epiphysis in establishing the stem cell niche for PTHrP⁺ chondrocytes, the absence of which may explain the lack of column-forming capabilities of PTHrP⁺ chondrocytes in the cranial base synchondrosis.

Double Vascularized Fibula Proximal Growth Plate Transplantation: Novel Technique for the Radial Longitudinal Deficiency (RLD) Grade IV Reconstruction

Radial absence or severe hypoplasia in radial longitudinal deficiency (RLD) is most commonly treated through stabilization of the carpus on the ulna (centralization or radialization) with or without preliminary distraction. Alternative methods include bone transfer to replace the absent or deficient radius using the proximal fibula, vascularized or nonvascularized, and more recently the transfer of a vascularized second metatarsophalangeal joint. There is paucity of articles suggesting vascularized fibula growth plate transfer for RLD grade III where proximal part of radius can be found and none about double fibular growth plate transplantation. We developed new technique a bilateral growth plate transplantation for the pediatric patient with unilateral RLD stage IV (Bayne and Klug). Totally 2 patients were operated using new technique. No vascular problems occurred and no peroneal nerve damage were observed at the follow-ups. Annual growth was determined on x-rays at the 1 and 2-year follow-ups measuring 0.75 to 0.9 cm with open growth plates. The x-rays also show no changes that can harm the long-term growth potential in the forearm, demonstrating this technique's capacity to achieve better results for forearm length and functionality in comparison to the Vilkki procedure or radialization operation and there is no need to sacrifice second toe. Thumb reconstruction can be done at age 3 or 4 years using pollicization or toe-to hand transplantation techniques. The patients and parents are satisfied with functional and esthetic outcomes. We believe the double fibular growth plate transplantation is a promising method to use to reconstruct unilateral RLD grade IV.

Prolonged non-weightbearing treatment decreases femoral head deformity compared to symptomatic treatment in the initial stage of Legg-Calvé-Perthes disease

The purpose of this study is to investigate the potential benefit of using prolonged non-weightbearing (PNWB) as a treatment option for early-stage Legg-Calvé-Perthes disease (LCPD). An Institutional Review Board (IRB) approved this retrospective study of patients with LCPD and ≥2-year follow-up. Patients 6-12 years of age were included if treatment began in Waldenstrom stage 1 or 2A. PNWB consisted of ≥6 months of non- or toe-touch weightbearing. PNWB was recommended if perfusion MRI demonstrated ≥40% hypoperfusion of the femoral head and parents decided against operative treatment. The control group consisted of symptomatically treated patients. Deformity index and epiphyseal quotient were measured at 2-year follow-up. Stulberg classification and sphericity deviation score (SDS) were determined at skeletal maturity or at a minimum of 5-year follow-up. When treatment was initiated in Waldenstrom stage 1, the PNWB group had significantly less femoral head deformity, including deformity index (0.21 vs. 0.52; P < 0.001), epiphyseal quotient (69% vs. 43%; P < 0.001), SDS (18 vs. 52; P = 0.004), and Stulberg (50% good vs. 0% good; P = 0.044). The PNWB group mean hypoperfusion was 68%, indicating severe hypoperfusion. Duration of recommended non-weight bearing in the PNWB group was 11.5 months (range 7-17 months). Despite severe femoral head hypoperfusion, PNWB begun during the initial stage of LCPD decreased femoral head deformity. PNWB should be considered a treatment option for patients/parents who do not wish to pursue operative intervention in early-stage LCPD with substantial hypoperfusion. Level of Evidence III - retrospective comparative study.

Prediction of Distal Femur and Proximal Tibia Bone Mineral Density From Total Body Dual Energy X-Ray Absorptiometry Scans in Persons with Spinal Cord Injury

Bone density decreases rapidly after spinal cord injury (SCI), increasing fracture risk. The most common fracture sites are at the knee (i.e., distal femur or proximal tibia). Despite this high fracture incidence, knee-specific scans for bone density using dual x-ray absorptiometry (DXA) were not available until 2014 and are still not routinely used in clinical practice today. This has made it difficult to determine the rehabilitation efficacy and hindered understanding of the long-term changes in knee areal bone density. The purpose of this investigation was to compare areal bone mineral density values for the knee from both total-body and knee-specific DXA scans in persons with SCI. A total of 20 participants (16 males) >1 yr-post spinal cord injury received two DXA scans; a total-body scan and a knee-specific scan. Standardized methods were used to create regions of interest to determine bone density of four regions - the epiphysis and metaphysis of the distal femur and proximal tibia - from the total-body scan. Linear regressions and Bland-Altman analyses were conducted to determine the correlation (r²) and agreement (mean bias ± 95% level of agreement) respectively between the two scan types for each region. Linear regression analyses showed strong significant (p < 0.001) relationships between the two scan types for the distal femur epiphysis (r² = 0.88) and metaphysis (r² = 0.98) and the proximal tibia epiphysis (r² = 0.88) and metaphysis (r² = 0.99). The mean bias ± 95% level of agreement were distal femur epiphysis (0.05 ± 0.1 g/cm²) and metaphysis (0.02 ± 0.04 g/cm²); proximal tibia epiphysis (-0.02 ± 0.1 g/cm²) and metaphysis (0.02 ± 0.03 g/cm²). Results suggest knee-specific bone density can be assessed using a total-body DXA scan. This may allow for more comprehensive use of DXA scans which would reduce the burden of multiple site-specific scans for persons with SCI and enable more widespread adoption of knee bone density assessment in this population.

Do Patient Demographics and Socioeconomic Status Influence Severity and Time to Diagnosis in Children With Stable Slipped Capital Femoral Epiphysis?

BACKGROUND

The time to diagnosis in stable slipped capital femoral epiphysis (SCFE) is often several months because of nebulous history, symptoms of knee/thigh pain, and Medicaid insurance. This study examined the impact of socioeconomic status and demographics on the time to diagnosis and SCFE severity in Indiana children.

METHODS

A retrospective review of all patients at a tertiary children's hospital with SCFE from January 2010 through March 2021 was performed. Standard demographic data and type of insurance was collected. Neighborhood Atlas Mapping was used to determine the state decile of the area deprivation index (ADI), a measure of socioeconomic status using 17 variables related to income, employment, education, and housing. Statistical analyses consisted of standard univariate and bivariate analyses; logistic regression analysis was used to determine predictors of a mild SCFE. A P<0.05 was considered statistically significant.

RESULTS

There were 142 patients; 81 male and 61 female. The average age was 12.2±1.7 years, lateral epiphyseal shaft angle of 35±19 degrees, and symptom duration of 4.5±5.0 months. There was no correlation between ADI state deciles and lateral epiphyseal shaft angle (r2=0.008) or symptom duration (r2=0.019). Insurance status and race differed by ADI deciles. In the first decile (least disadvantaged), 44% had government insurance and 89% were White; in the 10th decile (most disadvantaged), 95% had government insurance and 38% were White. Predictors of a mild SCFE were female sex [odds ratio (OR): 3.2 [1.5, 7.0]; P=0.004], symptom duration <3 months [OR: 5.3 (2.4, 11.7); P=0.00004], and White race [OR: 2.4 (1.3, 6.2); P=0.01]. Insurance status and ADI were not significant.

CONCLUSIONS

Contrary to other studies, neither insurance or socioeconomic status were associated with a delay in diagnosis or SCFE severity. The symptom duration in children with SCFE does not appear to be decreasing over the last several decades. Further investigation is required as to why.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Hegemann's Disease Detected with a Traumatic Olecranon Fracture: A Case Report

CASE

We describe a case of Hegemann's disease in a 10-year-old boy practicing karate. The disease was discovered by chance when evaluating a traumatic olecranon fracture. Radiography showed not only olecranon fracture but also a shortening of the epiphysis of the humeral trochlea and a segmental lesion with sclerosis. The trochlea lesion was considered asymptomatic Hegemann's disease. After the olecranon healed conservatively, the patient resumed karate activities and underwent follow-up radiography. The trochlea lesion gradually normalized after 2 years without symptoms.

CONCLUSIONS

Regardless of the initial alarming radiographic findings, the lesion gradually healed, and the patient was able to return to sports activities.

Effect of positioning error on the Hilgenreiner epiphyseal angle and the head-shaft angle compared to the femoral neck-shaft angle in children with cerebral palsy

Children with cerebral palsy (CP) often have changes in proximal femoral geometry. Neck-shaft angle (NSA), Hilgenreiner epiphyseal angle (HEA) and head-shaft angle (HSA) are used to measure these changes. The impact of femoral rotation on HEA/HSA and of ab/adduction on HEA/HSA/NSA is not well known. This study aimed to determine and compare the effect of rotation, ab/adduction and flexion/extension on HEA/HSA/NSA. Radiographic measurements from 384 patients with Gross Motor Function Classification System (GMFCS) levels I-V were utilized. NSA/HSA for affected hips were used with femoral anteversion averages to create three-dimensional models of 694 hips in children with CP. Each hip was rotated, ab/adducted and flexed/extended to simulate malpositioning. HEA/HSA/NSA of each model were measured in each joint position, and differences from correct positioning were determined. Mean HEA error at 20° of internal/external rotations were -0.60°/3.17°, respectively, with the NSA error of -6.56°/9.94° and the HSA error of -3.69°/1.21°. Each degree of ab/adduction added 1° of the HEA error, with no NSA/HSA error. NSA was most sensitive to flexion. Error for all measures increased with increasing GMFCS level. HEA/HSA were minimally impacted by rotation. NSA error was much higher than HEA/HSA in internal rotation and flexion whereas HEA was sensitive to changes in ab/adduction. Given abduction is more easily detectable on imaging than rotation, HEA may be less affected by positioning errors that are common with children with CP than NSA. HSA was least affected by position changes. HEA/HSA could be robust, complementary measures of hip deformities in children with CP.

Treatment of Recalcitrant Femoral Shaft Nonunion With Medial Femoral Condyle Pedicled Autograft: Technical Trick

SUMMARY

Nonunited fractures of the femoral shaft and distal femur are usually successfully addressed with stabilization with or without autogenous bone grafting. For the small subset of these problems that prove recalcitrant to front-line treatment, a pedicled medial femoral condyle (MFC) bone flap can provide a source of vascularized autograft with minimal donor site morbidity. The MFC has gained recent widespread adoption as a free vascularized bone transfer, and here, we present a surgical technique and retrospective analysis of patients treated with a pedicled MFC technique. This serves as a useful treatment option for these difficult problems and may be especially helpful in low resource environments or where microsurgical anastomosis is not feasible.

[Temporary Hemiepiphysiodesis in the Correction of Axial Deformities for Genua Valga: Retrospective Assessment and Comparison of Outcomes Achieved with the Use of Eight-Figure Plates and Blount Staples]

PURPOSE OF THE STUDY Axial deformities of the lower limbs of various aetiologies are relatively common orthopaedic diagnoses in paediatric population. Fixed deformity is an indication for correction in order to reduce the pain and to delay the early osteoarthrosis of adjacent joints and pain. Temporary hemiepiphysiodesis is technically a fairly simple method for modulating growth at the level of the growth plate and thus correcting the skeletal axis. MATERIAL AND METHODS 59 patients who underwent axial deformity correction of lower limbs at KDCHOT FN Brno were retrospectively analysed. Group 1 consisted of 21 patients with Blount staples implantation, Group 2 consisted of 38 patients to whom eight-figure plates had been applied. Anthropometric parameters (BMI, age, gender, intermalleolar distance (IMD)), duration of therapy, X-ray parameters (anatomical lateral distal femoral angle (aLDFA), anatomical medial proximal tibial angle (aMPTA)) and complications were recorded. The rate of correction was evaluated as the difference in X-ray parameters before and after surgery with respect to the time interval of the therapy. RESULTS The groups were comparable in terms of anthropometric parameters (BMI (p=0.800), IMD (p=0.334), gender (p=0.87)). The only statistically significant difference was found when comparing the mean age of the groups (p=0.005), with Group 1 (12.7±0.7) containing patients with a higher mean age than Group 2 (11.6±1.5). The groups were also comparable in terms of the average rate of correction over a one-month interval (aLDFA p=0.393; aMPTA p=0.831). The mean correction rate for Group 1 was: aLDFA 0.52±0.20/month, aMPTA 0.12±0.08/month; for Group 2: aLDFA 0.56±0.28/month, aMPTA 0.12±0.20/month. Individual implants differed in the type of complications, but no significant statistical difference in the incidence of complications was found between the analysed groups (p=0.526). DISCUSSION Recently, the system of eight-figure plates has been adopted as a standard method for correction of axial deformities of limbs. Although the benefits of this system are indisputable, when comparing the average monthly correction rate, no significant difference was found between the system of eight-figure plates and Blount staples in our study. Another monitored parameter was the occurrence of complications, which was evaluated fairly strictly. Even in this case, no statistically significant difference was found. We believe that the issue of using eight-figure plates is still open, as evidenced by studies, which often produce different results and conclusions. Therefore, a precise evaluation of the indication for correction, including individual characteristics of patients, is needed. CONCLUSIONS Based on the results, it can be concluded that the use of eight-figure plates in comparison with Blount staples provides neither faster correction of axial deformities nor lesser occurrence of complications. It can therefore be argued that the Blount staples still have their place in the indication of correction of axial deformities. The use of eight-figure plates represents a suitable solution for children of younger age to whom anchoring of the screws of eight-figure plates is a suitable solution in the cartilaginous epiphysis of long bones of younger children. Key words: temporary hemiepiphysiodesis, growth plate, Blount staples, eight-figure plates.

Management of a rare intra-articular fracture of the lateral femoral condyle: case report

Unicondylar fractures of the femur are uncommon injuries that can occur in the sagittal or, less frequently, in the coronal plane (Hoffa fractures).  Distal femoral fractures are usually described following the AO/OTA Classification system which includes extra-articular, partial articular and intra-articular injuries, further divided in three types based on the pattern and comminution.  Accurate reduction and stable fixation are needed especially in articular injuries in order to allow early mobilization and reduce complications such as knee stiffness, malunion or secondary osteoarthritis. The aim of this paper is to report a case of an unusual articular fracture of the lateral femoral condyle in a 39 years old man. This fracture reminds the pattern of a typical tibial plateau injury, not embedded in the most common descriptions of femoral traumas. Indeed, in most cases, high energy traumas in valgus of the knee result in a damage to the tibial plateau because of the condyles impact on the tibial articular surface, while in the present case the opposite occurred. The patient was successfully treated with an open reduction and fixation with two cannulated leg screws, reporting  good clinical outcome and excellent healing of the fragment evidenced with CT scan at 6 months follow-up.