Head Coverage Research Articles

Are some neutral liners more neutral than others? An ex vivo morphological analysis of acetabular liners classified as "neutral".

In contemporary total hip replacement (THR), dislocation is one of the most common complications. At our institution, the cause of an increase in the dislocation rate was recently reported to be reduced head coverage of a newly introduced neutral liner. We therefore aimed to ascertain whether differences exist in articulating head coverage between the various neutral liners used in contemporary THR. A secondary aim was to utilize coverage measurements to develop a new liner coverage classification. The articulating head coverage of 25 modular neutral polyethylene liners used in 6 uncemented cup designs from 4 major manufacturers was evaluated. The measurements were performed in a metrology laboratory and a mathematical model was developed to calculate coverage of the articulating surfaces. Further, 1 "elevated rim" liner and 1 "face changing liner" were included to develop a new liner coverage classification. The articulating head coverage among the studied liners ranged from 167.7° to 194.8°, corresponding to a variation of 27.1°. The variations with different cup and head sizes within each design were smaller (from 1.0° to 5.6°) than those between different designs. Each of the liner designs offered distinct coverage, even though they were all classified as neutral. Based on measurements, a set of descriptive parameters to discriminate different liners in terms of coverage was created. We showed that all neutral liners are not equal - instead, they clearly varied in terms of their actual coverage design. We suggest our set of descriptive parameters called "hemispheric coverage index values" be used in discriminating the differences in liner coverage.

Lower limb maltorsion and acetabular deformity in children and adolescents with X-linked hypophosphatemia.

X-linked hypophosphatemia (XLH) is a rare monogenetic skeletal disorder. Lower limb deformities contribute substantially to impaired gait quality and burden of disease in patients with XLH. Standardized data regarding onset and severity of lower limb maltorsion are unavailable. This study aimed to evaluate lower limb maltorsion using rotational magnetic resonance imaging (MRI) and computed tomography (CT). Rotational MRI and CT of children and adolescents with verified XLH were evaluated retrospectively. Femoral and tibial torsion, acetabular anteversion, and axial acetabular coverage were measured and compared with published age-adapted radiographic, clinical measurements and MRI data, respectively. Fifteen patients (mean age, 10.7 years) were included in the study. Decreased femoral torsion was observed in 47% (14/30 femora) and femoral retrotorsion in 17% (5/30 femora). Ten of 13 hips with coxa vara deformity presented with decreased femoral antetorsion. Reduced external tibial torsion manifested in 64% (18/28 tibiae). Abnormal axial femoral head coverage was present in 67% (20/30 hips), whereas 53% (16/30 hips) showed increased acetabular anteversion. Femoral and tibial torsional pathologies were found in children and adolescents with XLH. The occurrence of severe femoral retrotorsion in a 2-year-old child prior to ambulation raises questions regarding the biomechanical impact of gait on the development of torsional deformities in XLH.

Acetabular morphology variations in a Hispanic population.

Rotational abnormalities of the hip have been implicated in the etiology of diseases, such as hip dysplasia, osteoarthritis, and femoroacetabular impingement. Despite the extensive literature on hip morphology, there is a gap in knowledge regarding variations in the Hispanic population. To describe the bony anatomy variations of the acetabulum in a Hispanic population. This is a cross-sectional study. We studied 182 computed tomography (CT) images in patients aged older than 21 years, who had undergone pelvic CT for any condition, except hip fracture. Measurements of acetabular version, anterior and posterior acetabular sector angles (AASA/PASA) and horizontal acetabular sector angles (HASA) were made. Acetabular variations were then compared to weight and sex data. The mean acetabular anteversion was greater in women (P < 0.001). Women exhibited a greater PASA (P < 0.05); however, men had a greater AASA (P < 0.05). Underweight individuals had a smaller PASA (P < 0.01) and HASA (P < 0.05) than individuals with a normal weight. The Hispanic hip is morphologically similar to other populations previously reported in the literature; however, Hispanic men have less coverage of the femoral head by the posterior acetabular wall when compared to women of the same ethnicity. These abnormalities have a direct impact on management and surgical approach in patients treated for femoroacetabular impingement and hip dysplasia.

Three-dimensional assessment of subchondral arc and hip joint coverage angles in the asymptomatic young adult hip.

The primary objective of this study was to develop a custom algorithm to assess three-dimensional (3D) acetabular coverage of the femoral head based on surface models generated from computed tomography (CT) imaging. The secondary objective was to apply this algorithm to asymptomatic young adult hip joints to assess the regional 3D acetabular coverage variability and understand how these novel 3D metrics relate to traditional two-dimensional (2D) radiographic measurements of coverage. The algorithm developed automatically identifies the lateral- and medial-most edges of the acetabular lunate at one-degree intervals around the acetabular rim based on local radius of curvature. The acetabular edges and the center of a best-fit sphere to the femoral head are then used to compute the mean 3D subchondral arc angles and hip joint coverage angles in five acetabular octants. This algorithm was applied to hip models generated from pelvis/hip CT imaging or abdomen/pelvis CT angiograms of 50 patients between 17 and 25 years of age who had no history of congenital or developmental hip pathology, neuromuscular conditions, or bilateral pelvic and/or femoral fractures. Corresponding 2D acetabular coverage measures of lateral center edge angle (LCEA) and acetabular arc angle (AAA) were assessed on the patients' clinical or digitally reconstructed radiographs. The 3D subchondral arc angle in the superior region (58.0 [54.6-64.8] degrees) was significantly higher (p < 0.001) than all other acetabular subregions. The 3D hip joint coverage angle in the superior region (26.2 [20.7-28.5] degrees) was also significantly higher (p < 0.001) than all other acetabular subregions. 3D superior hip joint coverage angle demonstrated the strongest correlation with 2D LCEA (r = 0.649, p < 0.001), while 3D superior-anterior subchondral arc angle demonstrated the strongest correlation with 2D AAA (r = 0.718, p < 0.001). The 3D coverage metrics in the remaining acetabular regions did not strongly correlate with typical 2D radiographic measures. The discrepancy between standard 2D measures of radiographic acetabular coverage and actual 3D coverage identified on advanced imaging indicates potential discord between anatomic coverage and the standard clinical measures of coverage on 2D imaging. As 2D measurement of acetabular coverage is increasingly used to guide surgical decision-making to address acetabular deformities, this work would suggest that 3D measures of acetabular coverage may be important to help discriminate local coverage deficiencies, avoid inconsistencies resulting from differences in radiographic measurement techniques, and provide a better understanding of acetabular coverage in the hip joint, potentially altering surgical planning and guiding surgical technique.

Application of 3D-printed individualized porous tantalum buttress in shelf acetabuloplasty for developmental dysplasia of the hip

Shelf acetabuloplasty is a viable treatment for developmental dysplasia of the hip (DDH), yet autologous bone grafts have faced challenges such as morphological mismatch, imprecise placement, and long-term graft resorption. The rapid advancement of three-dimensional (3D) printing technology in orthopedics has enabled the acquisition of digital image correlation method (DICM) data from patient pelvic to bilateral femoral proximal regions through computed tomography (CT) scans. This data is then utilized by software to create 3D models and design individualized metal implants. Using tantalum-based TA1 type I spherical powder as the raw material, a porous tantalum buttress with a pore size of 600 microns and a porosity of 75% was fabricated employing the selective electron beam melting (SEBM) technology. Our Center has applied this 3D-printed individualized porous tantalum buttress in shelf acetabuloplasty for 21 DDH patients (25 hips), including 6 males and 15 females, with a mean age of (21.38&amp;plusmn;7.39) years. The follow-up period ranged from 12 to 47 months, averaging (22.64&amp;plusmn;10.86) months. At the final follow-up, patient-reported outcomes (PROs) were used to assess patient&amp;rsquo;s subjective feelings. Significant improvements were observed in the Non-Arthritic Hip Score (NAHS), modified Harris Hip Score (mHHS), Hip Outcome Score-Sports Subscale (HOS-SSS), International Hip Outcome Tool-12 (iHOT-12), and Visual Analog Scale (VAS) compared with preoperative levels (P&lt;0.01). Radiographic assessments showed that postoperative lateral center edge (LCE) angle, Tonnis angle, acetabular angle (Sharp&amp;rsquo;s angle), and femoral head coverage all trended towards normal, with statistically significant differences (P&lt;0.01). There was no implant displacement or bone resorption in any case, and no progression in Tonnis grading for hip osteoarthritis (OA) was noted postoperatively, with an 84% patient satisfaction rate. The early follow-up results of 3D-printed individualized porous tantalum buttress in shelf acetabuloplasty are satisfactory, indicating a reliable application prospect for the treatment of DDH patients.

Outcome One Year after Acetabular Rim Extension Using a Customized Titanium Implant for Treating Hip Dysplasia in Dogs.

The acetabular rim extension (ACE-X) implant is a custom-made three-dimensionally printed titanium device designed for the treatment of canine hip dysplasia. In this study, 34 dogs (61 hips) underwent ACE-X implantation, and assessments were conducted using computed tomography, force plate analysis, Ortolani's test, and the Helsinki chronic pain index (HCPI) questionnaires at five intervals: the pre-operative day, the surgery day, and the 1.5-month, 3-month, and 12-month follow-ups. Statistically significant increases in femoral head coverage with a negative Ortolani subluxation test were observed immediately after surgery and persisted throughout the study. Osteoarthritis (OA) scores remained stable, but osteophyte size significantly increased between the surgery day and the 12-month follow-up, especially in hips with a baseline OA score of 2 compared to those with a score of 1. The force plate data showed no significant changes during the study. The HCPI demonstrated a significant decrease in pain score from pre-operative value to six-week follow-up and gradually decreased over time. Major complications were identified in six hips (9.8%) of four dogs. In conclusion, the ACE-X implant effectively increased femoral head coverage, eliminated subluxation, and provided long-term pain relief with minimal complications, benefiting over 90% of the study population. The study supports the ACE-X implant as a valuable alternative treatment for canine hip dysplasia.

Methods for three-dimensional characterization of the acetabulum prior to pelvic reorientation osteotomy: a scoping review.

Periacetabular osteotomy is the gold standard treatment for acetabular dysplasia. The great variability of acetabular dysplasia requires a personalized preoperative planning improved by 3D reconstruction and computer-assisted surgery. To plan the displacement of the acetabular fragment by a pelvic osteotomy, it is necessary to define a reference plane and a method to characterize 3D acetabular orientation. A scoping review was performed on PubMed to search for articles with a method to characterize the acetabulum of native hips in a 3D reference frame. Ninety-eight articles out of 3815 reports were included. Three reproducible reference planes were identified: the anterior pelvic plane, the Standardization and Terminology Committee plane used in gait analysis, and the sacral base plane. The different methods for 3D analysis of the acetabulum were divided in four groups: global orientation, triplanar measurements, segmentation, and surface coverage of the femoral head. Two methods were found appropriate for reorientation osteotomies: the global orientation by a vector method and the triplanar method. The global orientation method relies on the creation of a vector from the acetabular rim, from the acetabular surface or from successive planes. Normalization of the global acetabular vector would correct acetabular dysplasia by a single alignment maneuver on an ideal vector. The triplanar method, based on angle measurements at the center of the femoral head, would involve correction of anomalies by considering axial, frontal, and sagittal planes. Although not directly fit for reorientation, the two others would help to candidate patients and verify both planning and postoperative result.

False-Profile Radiograph Sourcil-Edge and Bone-Edge Measurements Correlate to Different Weightbearing Regions of the Acetabulum: A 3-Dimensional Analysis

Background: The acetabular sourcil is commonly interpreted as a reliable radiographic representation of the weightbearing dome of the acetabulum, despite limited modern data. Assessment of weightbearing acetabular coverage has been described using both the sourcil edge and bone edge as anatomic landmarks, leading to confusion and potential misguidance in surgical decision-making and thus compromised patient outcomes. Purpose/Hypothesis: The purpose of this study was to characterize the 3-dimensional (3D) anatomic correlates of the sourcil-edge and bone-edge radiographic measurements on false-profile radiographs. It was hypothesized that the sourcil edge would represent anterolateral coverage and the bone edge would represent anterior coverage. Study Design: Descriptive laboratory study. Methods: A total of 80 hips were grouped by large or small differences between bone-edge and sourcil-edge anterior center-edge angles, based on upper and lower quartiles of discrepancy. Three-dimensional surface mesh models and digitally reconstructed radiographs were generated from hip computed tomography scans. Sourcil-edge and bone-edge anterior center-edge angles were identified on digitally reconstructed radiographs and registered to the 3D models with fiducial markers. Intersections of bone-edge and sourcil-edge projection lines with the acetabular rim were obtained from the 3D models. Results: The bone-edge and sourcil-edge projections intersected the acetabular rim at clockface means of 2:05 ± 0:22 and 1:12 ± 0:25, respectively. The 3D models consistently demonstrated that, in both large- and small-discrepancy groups, the sourcil edge corresponded to the acetabular area just posterior to the anterior inferior iliac spine (AIIS) projection, and the bone edge corresponded to the weightbearing region inferior to the AIIS. Additionally, in large-discrepancy hips, the bone edge corresponded to more prominent acetabular coverage in the region inferomedial to the AIIS when compared with the small-discrepancy hips. Conclusion: On false-profile radiographs, the sourcil edge corresponds to superior femoral head coverage, and the bone edge corresponds to anterosuperior coverage. Radiographs with a large discrepancy between sourcil-edge and bone-edge measurements demonstrate acetabular rim prominence in the region of the AIIS. Clinical Relevance: Characterizing the anatomic weightbearing regions of the acetabulum represented on false-profile radiographs facilitates improved clinical and intraoperative decision-making in hip preservation surgery, including acetabuloplasty and periacetabular osteotomy.

Universal ultrasound screening and early treatment of developmental dysplasia of the hip: a critical review.

Developmental dysplasia of the hip (DDH) is the most common musculoskeletal disease in infants, and delayed diagnosis can worsen the prognosis. Clinical evidence increasingly supports universal ultrasound (US) screening over selective US screening. The Graf method remains the most widely accepted US technique. Performing an US screening at one month of age seems appropriate as it allows for some hip maturity and early detection, thereby increasing the chances of a favorable outcome. This paper presents an approach to US findings based on the femoral head coverage method. Considering the long-term cost and psychosocial impact of missed DDH cases, universal ultrasound screening appears to be a cost-effective alternative.

Typical Development of the Secondary Ossification Centers of the Acetabulum and Their Effects on Acetabular Coverage of the Femoral Head.

We investigated the normal development of the secondary ossification centers of the acetabulum, focusing on their location and the amount of acetabular coverage increased by them. We enrolled 132 patients who were 7 to 16 years of age and had no pelvic deformity but did have ≥1 os ischium, os ilium, and/or os pubis on abdominal or pelvic computed tomographic (CT) scans. The locations of the ossification centers were evaluated by adopting an orientation using 0° for the superior acetabulum, 90° for the anterior acetabulum, 180° for the inferior acetabulum, and 270° for the posterior acetabulum, on a reconstructed 3-dimensional (3D) CT image. The acetabular coverage increase by the os ischium, os ilium, or os pubis was defined as the difference in the posterior acetabular sector angle (ΔPASA), posterosuperior acetabular sector angle (ΔPSASA), superior acetabular sector angle (ΔSASA), anterosuperior acetabular sector angle (ΔASASA), or anterior acetabular sector angle (ΔAASA) measured with and without each secondary ossification center. Patients were grouped into 3 age ranges: late childhood, preadolescence, and early adolescence. The location of each ossification center and the increase in acetabular coverage were compared between these groups. In the late-childhood group, the median start-to-end positions in right hips were 269° to 316° for the os ischium, 345° to 356° for the os ilium, and 81° to 99° for the os pubis. These positions tended to be wider in the early-adolescence group at 252° to 328° for the os ischium (p < 0.001), 338° to 39° for the os ilium (p = 0.005), and 73° to 107° for the os pubis (p = 0.049) in right hips. In right hips in the late-childhood group, the median values were 8.1° for ΔPASA, 14.0° for ΔPSASA, 9.9° for ΔSASA, 11.1° for ΔASASA, and 3.9° for ΔAASA; and in the early-adolescence group, the median values in right hips were 10.7° for ΔPASA, 12.9° for ΔPSASA, 8.4° for ΔSASA, 7.4° for ΔASASA, and 5.6° for ΔAASA. Only the median ΔPASA was larger in the early-adolescence group than in the late-childhood group (p = 0.026). Similar results were observed in left hips. In early adolescence, the secondary ossification centers appeared at more extended areas along the acetabular rim, and the increase in acetabular coverage by the secondary ossification centers tended to be larger in the posterior area but not in the anterior or superior area. Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Парсуна «Сююмбике с сыном Утямышем»: реальный образ или вымысел?

The object of the study is the parsuna “Syuyumbike with her son Utyamysh” as a historical and ethnographic source. The relevance of studying this type of visual materials lies in the possibility of identifying the transformation of Tatar women's costume. Taking into account the accumulated experience of ethnographic research and the preserved early written and visual materials, the article provides a comparative historical analysis of parsuna. The given piece, according to some estimates, dates back to the 17th–18th centuries. According to the author of the article, it was written no earlier than the beginning of the 19th century. The proposed dating is explained by the absence of characteristic elements of the Tatar woman's costume complex on the depicted Syuyumbike, which were present in drawn works of the earlier period. The image of Syuyumbike is reproduced in a young lady’s head-dress, which consists of a cone-shaped hat and a veil, and the woman next to her is wearing a women’s multi-piece head-dress. Taking into account the traditions of varying degrees of head coverage in the complexes of different age groups of Tatar women, we can conclude that the age of the depicted figures is clearly identifiable in the parsuna. The standing child, who is considered Utyamish, taking into account the early traditions of dressing boys in women’s clothing, is dressed in a girlish complex, repeating the image of a mother and a married woman. This is not typical of the traditional culture. In the 1850s edition, a similar piece was published, but “Syuyumbike” was not indicated in the title, which allows us to assume that that image was later included in an already existing image with reproduction of the clothes of young Tatar girls and married women.

Poster 208: Predicting Patient-Specific Hip Motion During Functional Activities After Periacetabular Osteotomy

Objectives: Developmental dysplasia of the hip (DDH) is a condition in which the hypoplastic acetabulum provides inadequate coverage of the femoral head. This abnormal coverage, while pathological, may be advantageous in some sporting and recreational activities needing significant hip range of motion (ROM), including dance, ballet, and performing arts. Although DDH allows patients to perform activities requiring supraphysiologic hip motion, subluxation of the hip joint generates excessive articular stresses, leading ultimately to pain, osteoarthritis (OA), and total joint arthroplasty. In some DDH patients, this degenerative pathway can be interrupted by performing a periacetabular osteotomy (PAO) to reorient the acetabular fragment, which increases femoral head coverage and reduces intra-articular stresses. This improved coverage is believed to come at the sacrifice of range of motion, particularly noticed while performing high-demand activities requiring supraphysiologic end-range motion. This study addresses the questions: 1. Does a PAO reduce the range of motion of the hip enough to reduce a patient’s ability to perform daily living, recreational and sporting activities? 2. If so, what activities are most impacted by these changes? Methods: We created an inventory of daily living, recreational and sporting activities commonly performed by patients with hip dysplasia. A systematic review of the literature provided the maximum hip range of motion required (required ROM) to perform eight activities of daily living (ADL) and thirteen sporting movements. The concurrent peak value for each anatomic component of hip motion, (i.e flexion/extension; adduction/abduction; internal/external rotation) was classified for every activity in terms of physiologic demand relative to the average ROM of the adult hip. Based on these values, we created a 7-level ordinal scale according to the peak kinematic demand required to perform each activity (Table 1), ranging from low to extreme difficulty. To examine the impact of a PAO on the limits of hip motion, we selected, with IRB approval, a cohort of 24 dysplastic hips (12 left and 12 right). Patient-specific 3D models of each pelvis and hip joint were created from preoperative CT scans, and each activity in our hip inventory was simulated using a custom Matlab hip simulation routine. For each activity, the ROM of the hip was recorded as the point at which either bony impingement was detected, or the specified movement was successfully completed. The percentage of the required motion successfully completed (percent function) was then calculated (100*measured ROM/required ROM) for each movement. This procedure was repeated on the same hips after completion of a computer-simulated PAO according to the technique described by Ganz and colleagues in which the LCEA was increased to 35° and reoriented anteriorly to appropriately restore head coverage. Wilcoxon Signed Rank tests were performed to compare preoperative and postoperative percent function for each movement. Results: When all activities were combined, there was no significant difference (p &gt; 0.05) between preoperative function (99.2 ± 0.6%) and postoperative function (98.0 ± 1.1%). The flexion portions of the right and left grand écart latéral, commonly used ballet movements, were the only activities where percent function was significantly decreased after PAO. Before surgery, the left hips performed 96.8 ± 1.8% of the motion required for the left grand écart latéral whereas after surgery hip function decreased to 82.5 ± 7.6% (p &lt; 0.05). Preoperatively, the right hips performed the right grand écart latéral at 96.7 ± 3.3% compared to 77.4 ± 8.3% postoperatively (p &lt; 0.05). There were no significant differences between preoperative and postoperative function for any other activities within the hip inventory. Conclusions: After testing a broad range of movements found in both daily life and sporting and recreational activities, just two of the twenty-one activities were significantly impaired after a computer-simulated PAO. A lack of significant change in percent function for most movements between preoperative and postoperative hips indicates that even high performing patients who undergo a PAO can expect little to no change in their ability to perform many of the activities they enjoyed before surgery. A significant change, however, was seen in the ballet positions right and left grand écart latéral and patients requiring performance of these activities after PAO should be counseled preoperatively regarding the demands of their sporting and recreational activities and their postoperative expectations. [Figure: see text]

Comparison of brace to observation in stable, radiological developmental dysplasia of the hip: a protocol for a global multicentre non-inferiority randomised trial

IntroductionBrace treatment is common to address radiological dysplasia in infants with developmental dysplasia of the hip (DDH); however, it is unclear whether bracing provides significant benefit above careful observation by...

Morphology of the dysplastic hip and the relationship with sex and acetabular version.

The dysplastic hip is characterized by incomplete coverage of the femoral head, resulting in increased risk of early osteoarthritis. The morphological variation of the hip joint is diverse and clear differences exist between females and males. The aim of this observational study was therefore to investigate the relationship between the morphology of the hip, sex, and hip dysplasia using a three-dimensional model. Statistical shape models of the combined femur and pelvic bones were created from bilateral hips of 75 patients. Using manual angle measurements and regression analysis, the characteristic shape differences associated with sex and hip dysplasia were determined. The model showed clear differences associated with sex and hip dysplasia. We found that the acetabular anteversion in females was significantly higher (p < 0.0001) than in males while no significant difference in acetabular anteversion was found between normal and dysplastic hips (p = 0.11). The model showed that decreased acetabular anteversion resulted in the appearance of the cross-over sign and the prominent ischial spine sign commonly associated with retroversion. Sex could be predicted with an area under the curve of 0.99 and hip dysplasia could be predicted with an area under the curve of ≥0.73. Our findings suggest that retroversion is a result of decreased anteversion of the acetabulum and is primarily associated with sex. This finding should be taken into account during the reorientation of the acetabulum in the surgical treatment of hip dysplasia.

Spatial pattern analysis of the impact of community food environments on foetal macrosomia, preterm births and low birth weight.

Community food environments (CFEs) have a strong impact on child health and nutrition and this impact is currently negative in many areas. In the Republic of Argentina, there is a lack of research evaluating CFEs regionally and comprehensively by tools based on geographic information systems (GIS). This study aimed to characterize the spatial patterns of CFEs, through variables associated with its three dimensions (political, individual and environmental), and their association with the spatial distribution in urban localities in Argentina. CFEs were assessed in 657 localities with ≥5,000 inhabitants. Data on births and CFEs were obtained from nationally available open-source data and through remote sensing. The spatial distribution and presence of clusters were assessed using hotspot analysis, purely spatial analysis (SaTScan), Moran's Index, semivariograms and spatially restrained multivariate clustering. Clusters of low risk for LBW, macrosomia, and preterm births were observed in the central-east part of the country, while high-risk clusters identified in the North, Centre and South. In the central-eastern region, low-risk clusters were found coinciding with hotspots of public policy coverage, high night-time light, social security coverage and complete secondary education of the household head in areas with low risk for negative outcomes of the birth variables studied, with the opposite with regard to households with unsatisfied basic needs and predominant land use classes in peri-urban areas of crops and herbaceous cover. These results show that the exploration of spatial patterns of CFEs is a necessary preliminary step before developing explanatory models and generating novel findings valuable for decision-making.

Acetabular dysplasia and posterior wall fractures: The missing link?

BackgroundTraumatologists are unable to predict hip instability based on CT scans and standard radiographs in posterior wall (PW) fractures comprising <50–60 % of the wall, necessitating an examination under anesthesia (EUA). Risk factors for instability have not been clarified, but acetabular dysplasia has been theorized as a potential etiology. Unfortunately, dysplasia is difficult to evaluate in the traumatic setting. The purpose of this study was to compare acetabular morphology between unstable and stable fractures with a novel method to detect dysplasia. MethodsPatients ≥ 18 years old with a PW fracture that underwent an EUA from 2013 to 2023 were retrospectively identified. For our experimental measurements, the axial distances on CT between the acetabular dome, lateral acetabular opening, and femoral head vertex were recorded. Acetabular geometry was quantified at these levels. Conventional dysplasia metrics (e.g., Tonnis angle) were obtained. Variables were compared between stable and unstable fractures. Results58 patients met inclusion criteria with 42 stable versus 16 unstable fractures. Unstable fractures had higher distances between the acetabular dome and femoral head vertex (p > 0.05). They had more cranial fracture exit points (p = 0.0015), lower femoral head coverage (p = 0.0102), and lower posterior acetabular sector angles (p = 0.0281). No other differences in acetabular geometry, demographics, injury characteristics, or other markers of dysplasia were identified. ConclusionsUnstable hips demonstrated a more recessed acetabular dome when compared to stable hips. Posterior acetabular femoral head coverage and cranial fracture exit point may be related to hip instability. A larger sample size is needed to validate these findings.

Surgical Technique of the 3-Dimensional-printed Personalized Hip Implant for the Treatment of Canine Hip Dysplasia.

Hip dysplasia causes major disability in dogs. Treatment options are limited to palliative treatment (e.g., pain relief, physical exercise, lifestyle changes, and weight control) or invasive surgeries such as pelvic osteotomies and total hip arthroplasty. Hence, a strong unmet need exists for an effective and dog-friendly solution that enhances the quality of life of man's best friend. We fill this treatment gap by offering a minimally traumatic and extraarticular, dog-specific, 3-dimensional-printed, hip implant (3DHIP) that restores hip joint stability. The surgical treatment using a 3DHIP implant is less invasive than osteotomies and can be performed bilaterally in one surgical session. The 3DHIP implant extends the dorsal acetabular rim of the dysplastic hip joint thereby increasing coverage of the femoral head and inhibiting joint subluxation with fast recovery. Sufficient access to the dorsal acetabular rim and ventral border of the iliac body together with optimal fitting and fixation of the implant are key steps for a successful 3DHIP implantation and imply the need for a specific approach. The present article aims to showcase this innovative surgical technique with tips and tricks as a surgical manual for implantation of the 3DHIP implant in dogs affected by hip dysplasia.

Annular Ligament Instability

Purpose: Lateral elbow pain is frequently attributed to epicondylalgia; yet, less common pathologies with limited literature representation exist. This study aims to delineate the diagnostic significance of alterations in the biomechanics and morphology of the annular ligament as a distinctive factor in lateral elbow pain. Methods: A retrospective observational analysis was conducted on patients surgically treated for lateral elbow pain with arthroscopic assistance from January 2015 to December 2018. Initial preoperative diagnoses primarily indicated epicondylalgia. Results: The study encompassed 82 patients (48 men, 34 women; mean age: 44.6 ± 5.3 years), with 91.46% involved in demanding manual work. Notably, 17 patients underwent surgery due to recurrent symptoms. Arthroscopic assessments revealed diverse morphological and biomechanical variations in annular ligaments, designating 36 patients with an identified incompetent annular ligament. Conclusions: Our arthroscopic study on lateral epicondylalgia cases involved a comprehensive analysis of annular ligament anatomy and radiocapitellar joint biomechanics. The formulated anatomic classification, incorporating crucial variables such as radial head coverage and ligament tension, unveiled implications for joint instability. Recognition of simultaneous pathologies, notably annular ligament lesions, signifies a potential, yet unexplored, avenue for differential diagnosis in cases of lateral elbow pain.

Comparison of Two Surgical Approaches for Periacetabular Osteotomy: A Retrospective Study of Patients with Developmental Dysplasia of the Hip.

Given the intricate challenges and potential complications associated with periacetabular osteotomy (PAO) for developmental dysplasia of the hip (DDH). Our study aimed to compare the clinical and imaging benefits and drawbacks of two surgical approaches, the modified Stoppa combined iliac spine approach and the modified Smith-Peterson approach, for treating PAO and to provide guidance for selecting clinical approaches. A retrospective analysis of 56 patients with 62 DDHs was conducted from June 2018 to January 2022. The experimental group underwent surgery via the modified Stoppa combined iliac spine approach, while the control group underwent surgery via the modified Smith-Peterson approach for periacetabular osteotomy and internal fixation. Basic statistical parameters, including age, sex, BMI, and preoperative imaging data, were analyzed. Differences in surgical time, intraoperative blood loss, and postoperative imaging data were compared, as were differences in preoperative and postoperative imaging data between the two groups. There were 28 hips in the experimental group and 34 in the control group. Moreover, there was no significant difference in the basic parameters between the experimental and control groups. Before and after the operation, for the LCE angle, ACE angle, and Tonnis angle, there was no significant difference in acetabular coverage (p > 0.05). However, there were significant differences between the two groups in terms of the above four indicators before and after the operation (p < 0.05). After the operation, the experimental group exhibited significant increases in both lateral and anterior acetabular coverage of the femoral head. However, the experimental group had longer operation times and greater bleeding volumes than did the control group. Despite this, the experimental group demonstrated significant advantages in protecting the lateral femoral cutaneous nerve compared to the control group. The modified Stoppa combined iliac spine approach can be considered a practical approach for PAO and is more suitable for patients with DDH who plan to be treated by one operation than the classic modified Smith-Peterson approach for PAO.

Prediction of 3-Dimensional Coverage Surface Area of the Femoral Head in Hip Dysplasia Through Conventional Computed Tomography.

Assessment of 3-dimensional (3D) femoral head coverage is critical in evaluating, preoperative planning, and treating hip dysplasia. To (1) propose a mathematical model to establish 3D femoral head coverage using conventional computed tomography (CT), (2) determine the correlation of 2D parameters with 3D coverage, and (3) characterize the patterns of dysplasia based on 3D morphology. Cross-sectional study; Level of evidence, 3. We identified 30 patients (n = hips) with symptomatic dysplasia and 30 patients (n = hips) without dysplasia. Patients with dysplastic hips were matched with regard to sex, age, and body mass index to those with nondysplastic hips. Preoperative CTs were analyzed using 3D software, and 3D femoral head surface area coverage (FHSAC; in %) was assessed in 4 quadrant zones: anteromedial, anterolateral, posteromedial, and posterolateral. To assess lateral coverage of the femoral head, we introduced the anterolateral femoral head coverage angle (ALFC) and the posterolateral femoral head coverage angle (PLFC). Reduced femoral head coverage was more pronounced in dysplastic versus nondysplastic hips in the anterolateral quadrant (18% vs 40.7%, respectively) and posterolateral quadrant (35.8% vs 56.9%, respectively) (P < .0001 for both). Dysplastic hips had smaller ALFC and PLFC (18.4° vs 38.7°; P < .0001; 47.2° vs 72.3°; P = .0002). Anterolateral and posterolateral FHSAC were strongly correlated with the ALFC (r = 0.88; P < .0001) and the PLFC (r = 0.82; P < .0001) along with the lateral center-edge angle (anterolateral, r = 0.75; P < .0001; posterolateral, r = 0.73; P < .0001). Prediction models established for FHSAC had strong agreement with explanatory CT variables (anterolateral: r = 0.91; P < .0001; posterolateral: r = 0.90; P < .0001). The cutoff values for anterolateral and posterolateral FHSAC were 25% and 41%, respectively. In dysplastic hips, global deficiency was most common (15/30 hips), 9 hips showed an anterolateral deficiency, and 4 hips had a posterolateral deficiency pattern. The ALFC and The PLFC were strongly correlated with 3D lateral FHSAC and were able to predict 3D coverage accurately.