Search Results (12)

(1) Background: This publication focuses on processes that disrupt the proper development of the hip. Four pathomechanisms underlying human developmental defects are described in the literature, i.e., dysplasia, malformation, disruption, and deformity. In the case of hip development, arguably the greatest challenge involves confusion between dysplasia and deformity, which often leads to misdiagnosis, incorrect nomenclature, and incorrectly chosen treatment. (2) Methods: A review of the scientific literature was performed. (3) Results: The paper presents a description of hip joint development disorders in the context of their pathomechanisms. An attempt was made to answer the question of whether these disorders are rooted in a primary disorder of tissue growth, resulting in incorrect anatomy, or are the result of anatomical deformations with secondary modifications in tissue structures—of a degenerative or adaptive nature—based on Delpech–Hueter–Volkmann growth and remodeling laws. In addition, the emphasis is placed on the presence of so-called clinically and diagnostically mute cases. We suggest augmenting diagnostic procedures with genetic tests to increase the sensitivity of screening. (4) Conclusions: Based on the arguments, a new division of developmental hip disorders is proposed. Full article

Background/Objectives: The stability of dual mobility (DM) total hip arthroplasty (THA) is often attributed to reduced impingement incidence and a superior range of motion (ROM) compared to the corresponding values when standard implants are used. However, few studies have directly explored this. Thus, the purpose of the present study was to compare the incidence of impingement and the range of motion between standard and DM acetabular cups, whose diameters are suited to the same patient anatomy. Methods: One standard and two DM implants were virtually implanted into a pelvis using a previously developed geometric model. Joint motions, which were representative of seven dislocation-prone activities of daily living (ADLs), as well as walking, were applied to each device type at a range of cup orientations (inclination/anteversion). Conclusions: There were no placement positions that avoided impingement across all seven ADLs, regardless of cup construct type. A similar impingement incidence and ROM were observed for standard and DM constructs, although the consequences of impingement are potentially more serious for DM devices (metal–metal contact) than for standard constructs (metal–polyethylene contact). This finding contradicts the common notion that DM-THAs have a reduced impingement incidence and superior ROM, instead suggesting that their stability may be attributed to alternative mechanisms, such as increased jump distance. Full article

Background: Knowledge of the relative contributions to different growth areas in the proximal femur and acetabulum is limited due to the complex anatomy and lack of growth markers in children. There is increasing interest in using guided growth to improve hip joint stability and decrease dysplasia in children with neurological disability. Some children with cerebral palsy (CP) are treated with bisphosphonates for bone insufficiency, which leaves a dense growth arrest band in the bone at the time of treatment. The aim of this study was to develop a novel approach to understand the growth and maturation impact on hip development in children with CP using this growth arrest band. Methods: Pelvic radiographs of children with CP Gross Motor Function Classification System (GMFCS) level IV/V treated with bisphosphonate were analyzed. We measured neck–shaft angle (NSA), head–shaft angle (HSA), and migration percentage (MP) based on pamidronate bands (PamMP), NSA based on pamidronate bands (PamNSA), and HSA based on pamidronate bands (PamHSA). These measurements were compared using t-test. Results: Seven children (two GMFCS IV and five GMFCS V) were included. The mean age of the radiographic assessment was 11.4 ± 1.3 (range, 8.6–12.5) years, mean MP 22 ± 7% (range, 13–39%), PamMP 33 ± 7% (range, 18–46%), NSA 151 ± 7° (range, 140–161°), PamNSA 153 ± 4° (range, 142–163°), HSA 164 ± 12° (range, 142–175°), and PamHSA 169 ± 8° (range, 154–175°). MP decreased by 10.5% compared with PamMP (p < 0.001). NSA compared with PamNSA (p = 0.117) and HSA compared with PamHSA (p = 0.325) were not statistically different. Conclusions: This novel assessment method demonstrates that ossification of the lateral acetabulum and femoral head in children with CP GMFCS IV/V from age 8 to 12 years undergoes a mean decrease of 10% MP. A decrease of 10% MP after proximal femoral-guided growth has been reported as a positive outcome. However, based on the current measurements, this may be due to normal development. HSA and NSA remained unchanged. Full article

Life expectancy and overall function of amputated patients have improved significantly over the last few decades; for this reason, amputees are more exposed to primary or secondary degenerative disease of the hip, requiring total hip arthroplasty (THA) surgery. However, during training, not all the surgeons acquire adequate skills to manage these patients, and only a few studies and case reports describe technical pearls and outcomes of THA in patients with ipsilateral lower limb amputation, either above or below the knee. The objective of this narrative review is to present current evidence and surgical tips for performing THA in ipsilateral amputated patients, with a focus on the differences between patients with above- (AKA) and below-knee amputation (BKA). We reviewed manuscripts in major scientific databases, cross-referencing to retrieve adjunctive manuscripts, and summarized all relevant cases. We found 17 manuscripts, spanning 70 years of literature, collecting a total of 39 patients who underwent THA on an ipsilateral amputated limb: 13 AKA, 23 BKA, and 3 through-knee-amputation (TKA). The cohort primarily consists of patients with post-traumatic hip arthritis, often associated with sequelae such as fractures to other bones, soft tissue compromise and heterotopic calcifications. Managing with amputated patients requires careful planning, which includes the study of the residual bone, muscle anatomy, and the level of femoral amputation, as these factors present significant surgical challenges, especially in patients without a knee joint. In dealing with the post-traumatic and multi-comorbidity patients, rehabilitation goals should be considered prior to surgery and should drive the surgical strategy. We found that BKA patients typically have high functional demands, necessitating precise positioning of the components and an aggressive post-operative physiotherapy regimen to avoid unsatisfactory outcomes. AKA patients, on the other hand, often present with altered anatomy, and typically require more surgical instruments and expertise to achieve intraoperative dislocation of the hip joint. Full article

Groin pain syndrome (GPS) is often a diagnostic challenge for sport physicians. Despite this diagnostic difficulty, the incidence of GPS in athletes is relatively high, afflicting 10–20% of the total sports population. In the literature, a certain number of studies demonstrate an important gender-based difference in the incidence of GPS in both sexes, with a ratio of female:male athletes clearly in favor of the female gender being relatively less prone to GPS. Indeed, some anatomical differences between the two sexes seem to represent a protective factor against the onset of GPS in women, although the current literature still needs to clarify the validity of these findings. It is the aim of this systematic review to examine all the anatomical differences between men and women that may be responsible for the difference in the onset of GPS in the two sexes. Full article

Despite the high success rate of primary total hip replacement (THR), a significant early revision rate remains, which is largely attributed to instability and dislocations. Despite the implants being placed according to the safe zone philosophy of Lewinnek, occurrence of THR dislocation is not an uncommon complication. Large diagnostic and computational model studies have shown variability in patients’ mobility based on the individual anatomic and functional relationship of the hip–pelvis–spine complex. The absolute and relative position of hip replacement components changes throughout motion of the patient’s body. In the case of spinopelvic pathology such as spine stiffness, the system reaches abnormal positional states, as shown with computerized models. The clinical result of such pathologic hip positioning is edge loading, implant impingement, or even joint dislocation. To prevent such complications, surgeons must change the dogma of single correct implant positioning and take into account patients’ individualized anatomy and function. It is essential to broaden the standard diagnostics and their anatomical interpretation, and correct the pre-operative surgical planning. The need for correct and personalized implant placement pushes forward the development and adaptation of novel technologies in THR, such as robotics. In this current concepts narrative review, we simplify the spinopelvic biomechanics and pathoanatomy, the relevant anatomical terminology, and the diagnosis and management algorithms most commonly used today. Full article

Hip pain is indubitably a frequent clinical problem deriving from copious etiologies. Hip impingement syndromes are one of the most prevalent causes of persistent groin pain, especially in young and active patients. Diligent imaging of the hip region is indispensable to discern femoroacetabular impingement, as the differential diagnosis of hip pain can be exceedingly arduous. Despite hip radiography being plain and broadly attainable, it offers narrow information concerning soft tissue pathologies around the hip joint (extra-articular hip impingement syndromes). Magnetic resonance imaging and arthrography remain the gold standard examination for detecting intra-articular pathologies; however, they are widely considered expensive, time-consuming and characterized by confined. Consequently, ultrasonography has emerged as an alternative valuable diagnostic tool for distinguishing the underlying abnormalities that trigger femoroacetabular impingement. Proper hip ultrasound examination provides dynamic assessment, while also beneficial for guided intervention around the hip joint. Ultrasound hip examination is exacting due to its complex regional anatomy and deep location. It is capable of providing detailed information about various hip quadrants. An adept operator can identify both intra-articular and extra-articular pathologies. In addition, with ultrasonography, hip injections have been rendered relatively undemanding, aiding in therapeutic and diagnostic purposes. This paper aims to provide a succinct and compendious review of the existing literature, accentuating the crucial role of ultrasonography in diagnosing hip impingement syndromes and determining whether an additional examination is required regarding distinguishing between intra-articular and extra-articular syndromes. Full article

Ankle foot orthoses (AFOs) are medical devices prescribed to support the foot and ankle of drop-foot patients. Passive-dynamic AFOs (PD-AFOs) are an effective solution for less severe cases. While off-the-shelf PD-AFOs are rather inexpensive, they provide poor anatomical fit and do not account for the required patient-specific biomechanical support. Three-dimensional (3D) scanning and manufacturing technologies allow manufacturing PD-AFOs customized for the patient’s anatomy and functional needs. This paper aimed to report the overall procedure for designing and manufacturing a novel, fiberglass-reinforced polyamide, custom PD-AFO. The feasibility of the proposed procedure was tested in a case study. The methodology can be divided into the following steps: (i) foot and leg scanning, (ii) 3D design, and (iii) additive manufacturing via selective laser sintering. A custom PD-AFO was designed and manufactured for a 67-year-old male drop-foot patient following paraparesis in severe discarthrosis after spine stabilization surgery. AFO mechanical properties were measured via an ad hoc setup based on a servohydraulic testing machine. The functional outcome was assessed via gait analysis in three conditions: shod (no AFO), wearing an off-the-shelf PD-AFO, and wearing the patient-specific PD-AFO. As expected, wearing the PD-AFO resulted in increased ankle dorsiflexion in the swing phase with respect to the shod condition. Sagittal rotations of the hip, knee, and ankle joints were similar across PD-AFO conditions, but the custom PD-AFO resulted in faster walking speed with respect to the off-the-shelf (walking speed: 0.91 m/s versus 0.85 m/s). Additionally, the patient scored the custom PD-AFO as more comfortable (VAS score: 9.7 vs. 7.3). While the present analysis should be extended to a larger cohort of drop-foot patients, the novel PD-AFO seems to offer a valid, custom solution for drop-foot patients not satisfied with standard orthotics. Full article

Background Relevant criteria for total hip arthroplasty (THA) planning have been introduced in the literature which include the hip range of motion, bony coverage, anterior cup overhang, leg length discrepancy, edge loading risk, and wear. The optimal implant design and alignment depends on the patient’s anatomy and patient-specific functional parameters such as the pelvic tilt. The approaches proposed in literature often consider one or more criteria for THA planning. but to the best of our knowledge none of them follow an integrated approach including all criteria for the definition of a patient-specific combined target zone (PSCTZ). Questions/purposes (1) How can we calculate suitable THA implant and implantation parameters for a specific patient considering all relevant criteria? (2) Are the resulting target zones in the range of conventional safe zones? (3) Do patients who fulfil these combined criteria have a better outcome score? Methods A method is presented that calculates individual target zones based on the morphology, range of motion and load acting on the hip joint and merges them into the PSCTZ. In a retrospective analysis of 198 THA patients, it was calculated whether the patients were inside or outside the Lewinnek safe zone, Dorr combined anteversion range and PSCTZ. The postoperative Harris Hip Scores (HHS) between insiders and outsiders were compared. Results 11 patients were inside the PSCTZ. Patients inside and outside the PSCTZ showed no significant difference in the HHS. However, a significant higher HHS was observed for the insiders of two of the three sub-target zones incorporated in the PSCTZ. By combining the sub-target zones in the PSCTZ, all PSCTZ insiders except one had an HHS higher than 90. Conclusions The results might suggest that, for a prosthesis implanted in the PSCTZ a low outcome score of the patient is less likely than using the conventional safe zones by Lewinnek and Dorr. For future studies, a larger cohort of patients inside the PSCTZ is needed which can only be achieved if the cases are planned prospectively with the method introduced in this paper. Clinical Relevance The method presented in this paper could help the surgeon combining multiple different criteria during THA planning and find the suitable implant design and alignment for a specific patient. Full article

Modular hip joint implants were introduced in arthroplasty medical procedures because they facilitate the tailoring of patients’ anatomy, the use of different materials in one single configuration, as well as medical revision. However, in certain cases, such prostheses may undergo deterioration at the head–neck junctions with negative clinical consequences. Crevice-corrosion is commonly invoked as one of the degradation mechanisms acting at those junctions despite biomedical alloys such as Ti6Al4V and CoCr being considered generally resistant to this form of corrosion. To verify the occurrence of crevice corrosion in modular hip joint junctions, laboratory crevice-corrosion tests were conducted in this work under hip joint-relevant conditions, i.e., using similar convergent crevice geometries, materials (Ti6Al4V and CoCr alloys vs. ceramic), surface finish, NaCl solution pHs (5.6 and 2.3), and electrochemical conditions. A theoretical model was also developed to describe crevice-corrosion considering relevant geometrical and electrochemical parameters. To verify the model, a FeCr alloy, known to be sensitive to this phenomenon, was subjected to the crevice-corrosion test in sulfuric acid. The experiments and the model predictions clearly showed that, in principle, crevice corrosion of Ti6Al4V or CoCr is not supposed to occur in typical crevices formed at the stem-neck junction of hip implants. Full article

In this paper, a novel 3D vector field convolution (VFC)-based B-spline deformation model is proposed for accurate and robust cartilage segmentation. Firstly, the anisotropic diffusion method is utilized for noise reduction, and the Sinc interpolation method is employed for resampling. Then, to extract the rough cartilage, features derived from Hessian matrix are chosen to enhance the cartilage, followed by binarizing the images via an optimal thresholding method. Finally, the proposed VFC-based B-spline deformation model is used to refine the rough segmentation. In the experiments, the proposed method was evaluated and demonstrated on 46 magnetic resonance images (MRI) (including 20 hip joints and 26 knee joints), and the results were compared with three state-of-the-art cartilage segmentation methods. Both qualitative and quantitative segmentation results indicate that the proposed method can be deployed for accurate and robust cartilage segmentation. Furthermore, from the segmentation results, patient-specific 3D models of the patient’s anatomy can be derived, which then can be utilized in a wide range of clinical applications, such as 3D visualization for surgical planning and guidance. Full article

Total hip arthroplasty has been utilized for the past 50 years as an effective treatment for degenerative, inflammatory and traumatic disorders of the hip. The design of these implants has generally followed the anatomy of the hip as a ball and socket joint with the femoral head representing the ball and the acetabulum representing the socket. We describe a novel hip arthroplasty design in which the “ball” is located on the acetabular side and the “socket” is located on the femoral side. The results of extensive biomechanical testing are described and document wear and corrosion characteristics that are at least equivalent to standard designs. These results support clinical assessment as the next step of the evaluation. Full article