Radiographic Measurements of the Hip Joint in Capuchin Monkeys (Sapajus spp.).

BACKGROUND: Radiographs are useful for the initial evaluation of the hip joints. The information can be utilized for the betterment of animal health or other goals such as anatomic studies and gait analysis, among others. Therefore, this study aimed to evaluate radiographic measurements of the hip joint in capuchin monkeys, kept under human care at a reference center for wildlife. METHODS: Twelve capuchin monkeys (Sapajus spp.) (three adult males, seven adult females, and two sub-adult females) were evaluated. Ventrodorsal radiographic views were taken under chemical restraint. All measurements on the digital images were performed in triplicate by one examiner. RESULTS AND CONCLUSIONS: None of the measurements evaluated were statistically different between males and females. No statistical differences were found between hind limbs. The mean (±SD) Norberg angle was 104.92° (±2.82°) and the Wiberg angle was 15.26° (±1.86°). The percentage of the femoral head covered by the acetabulum was 68.57% (±3.65%) and the acetabular index depth to width ratio was 54.66% (±3.85%). In conclusion, the radiographic measurements showed certain morphological features of the hip joint in Sapajus spp. that contribute to improving species knowledge.

A retrospective cohort study: dual cannula combined with modified shoelace continuous capsular closure technique versus nonrepair in hip arthroscopic surgery of femoroacetabular impingement.

BACKGROUND: Over the years, with the improvement of diagnostic and therapeutic capabilities for hip joint diseases and the advancements in surgical technology, hip arthroscopy has been extensively used. At present, there is ongoing controversy among scholars about whether it is necessary to close the joint capsule after hip arthroscopy. In addition, the clinical effect of repairing the hip joint capsule after hip arthroscopy remains uncertain. PURPOSE: To evaluate the effect of our modified shoelace suture technique on postoperative hip function and to investigate whether complete closure of the hip capsule is reliable and safe. STUDY DESIGN: Retrospective study; Levels of evidence: III. METHODS: A retrospective review was conducted on patients undergoing hip arthroscopy by a solitary high-volume hip arthroscopic surgeon. The patients were categorized into two groups. The first group consisted of patients who underwent the modified shoelace continuous capsular closure technique. The other group consisted of those who did not receive capsular closure after hip arthroscopy. Patient-reported outcomes including modified Harris Hip Score (mHHS), Hip Outcome Score of Activities of Daily Living (HOS-ADL), Hip Outcome Score Sport-Specific Subscale (HOS-SSS), and visual analogue scale (VAS) were obtained at a minimum of 12 months. Any complications during follow-up were identified and recorded. RESULTS: A total of 100 patients were followed up for 12-15 months, with an average of (12.3 ± 5.3) months in the study. There were 50 patients in the shoelace capsular closure group (CC group) and 50 patients in the non-capsular closure group (NC group). The surgical time in the suture group was significantly longer than that in the non-suture group. However, there was no statistically significant disparity in the length of hospital stay between the two groups. The mHHS, HOS-SSS, HOS-ADL, and VAS of the CC and NC group were significantly improved compared to preoperative scores at 6 and 12 postoperative months (P < 0.001). Compared with the NC group, the CC group showed a significant improvement in the mHHS, HOS-SSS, HOS-ADL, and VAS at 6 postoperative months (t = 4.885, P<0.001; t = 5.984, P<0.001; t = 4.279, P<0.001; t = 3.875, P<0.001). The mHHS, HOS-SSS, HOS-ADL, and VAS at 12 postoperative months were significantly better in the CC group than in the NC group (t = 5.165, P<0.001; t = 3.697, P<0.001; t = 4.840, P<0.001; t = 3.579, P = 0.001). There were no serious complications during the perioperative period. CONCLUSION: The modified shoelace continuous capsular closure technique is a reliable and secure method that can be used as an alternative to the conventional capsular closure. It is recommended to perform routine intraoperative repair of the articular capsule at the end of hip arthroscopy, as this has a positive influences on the functional results at short-term follow-up.

Offset Considerations in Total Hip Arthroplasty.

To perform total hip arthroplasty (THA) successfully, a surgeon must be able to place the implants in a position that will restore and duplicate the patient's baseline anatomy and soft-tissue tension. One of the critical factors is the restoration of femoral offset. It is the goal of this review to precisely define measurement of offset in THA, describe its role in hip joint biomechanics, outline alterations that can be performed intraoperatively, and explain how it can create potential pathologic states. If there is a lack of offset restoration, it can result in a host of complications, including bony impingement with pain, edge loading or prosthetic joint instability, and alterations in the muscle length-tension relationship leading to reduced motor performance. Excessive femoral offset can increase hip abductor muscle and iliotibial band tension resulting in greater trochanteric pain regardless of the surgical approach. The purpose of this review was to analyze intraoperative surgical factors, choice of prosthetic implant type and position that are required to maximize stability, and dynamic motor performance after THA.

A comprehensive predictive model for postoperative joint function in robot-assisted total hip arthroplasty patients: combining radiomics and clinical indicators.

Total hip arthroplasty (THA) effectively treats various end-stage hip conditions, offering pain relief and improved joint function. However, surgical outcomes are influenced by multifaceted factors. This research aims to create a predictive model, incorporating radiomic and clinical information, to forecast post-surgery joint function in robot-assisted THA (RA-THA) patients. The study set comprised 136 patients who underwent unilateral RA-THA, which were subsequently partitioned into a training set (n = 95) and a test set (n = 41) for analysis. Preoperative CT imaging was employed to derive 851 radiomic characteristics, selecting those with an intra-class correlation coefficient > 0.75 for analysis. Least absolute shrinkage and selection operator regression reduced redundancy to six significant radiomic features. Clinical data including preoperative Visual Analog Scale (VAS), Harris Hip Score (HHS), and Western Ontario and McMaster University Osteoarthritis Index (WOMAC) score were collected. Logistic regression identified significant predictors, and three models were developed. Receiver operating characteristic and decision curves evaluated the models. Preoperative VAS, HHS, WOMAC score, and radiomics feature scores were significant predictors. In the training set, the AUCs were 0.835 (clinical model), 0.757 (radiomic model), and 0.891 (combined model). In the test set, the AUCs were 0.777 (clinical model), 0.824 (radiomic model), and 0.881 (combined model). The constructed nomogram prediction model combines radiological features with relevant clinical data to accurately predict functional outcomes 3 years after RA-THA. This model has significant prediction accuracy and broad clinical application prospects and can provide a valuable reference for formulating personalized treatment plans and optimizing patient management strategies.

Effects of Ward Noise Management on Mental Health and Hip Function in Elderly Patients Undergoing Total Hip Arthroplasty.

OBJECTIVE: The aim of this study was to explore the influence of ward noise management on the mental health and hip joint function of elderly patients post-total hip arthroplasty. METHODS: The retrospective analysis involved the medical records of 160 elderly patients who underwent total hip arthroplasty at Nanchang First Hospital from March 2021 to January 2023. The observation group received ward noise management (n = 75) and the control group received perioperative routine management (n = 85). The noise level, Self-rating Depression Scale (SDS), Self-rating Anxiety Scale (SAS), the Generic Quality of Life Inventory-74 (GQOLI-74), Harris Hip Score (HHS) system, and satisfaction scale were used to evaluate patients. T test and chi-square tests were used for statistical analysis. RESULTS: The observation group exhibited a significantly lower noise level compared to the control group (P < 0.05). No significant differences were observed in the general information and preoperative SDS, SAS, HHS, and GQOLI-74 scores between the two groups (P > 0.05). No significant differences were observed in the SDS and HHS between the two groups 7 days after the operation (P > 0.05). The observation group presented a significantly lower SAS score than the control group 7 days after the operation (P < 0.05). The score of the observation group 7 days after the operation was lower than that before the operation (P < 0.05). At 7 days after the operation, the observation group showed a higher score in the "social function" dimension of GQOLI-74 compared to the control group (P < 0.05), and the satisfaction of the observation group was significantly higher than that of the control group (94.67 vs. 77.65%, P < 0.05). CONCLUSIONS: Ward noise management can help reduce anxiety among elderly patients after total hip arthroplasty, improve their quality of life and social function, and obtain higher satisfaction.

Neurogenic Heterotopic Ossification of the Hip: a Case Report.

Heterotopic ossification (HO) denotes aberrant osteogenesis in extra-skeletal tissues, often associated with neurological disorders, total hip arthroplasty, and specific traumatic scenarios. Neurogenic heterotopic ossification manifests prominently subsequent to traumatic brain injury or spinal cord injury, with Guillain-Barre Syndrome presenting an infrequent etiological link. This article details the case of a 56-year-old female diagnosed with Guillain-Barre Syndrome, who developed neurogenic heterotopic ossification around both hips within two years of disease onset. The patient's medical history included mechanical ventilation, incomplete tetraplegia, and prolonged immobilization. A conclusive diagnosis of HO was established through radiological and clinical assessments. After neurogenic heterotopic ossification was confirmed, the patient had surgery to remove the lesions, radiation therapy, and medication treatments as planned. Physical therapy was introduced one week post-surgery, with subsequent follow-ups tracking improvements in pain levels, range of motion (ROM), and Activities of Daily Living scores. Key words: neurogenic heterotopic ossification, Guillain-Barre syndrome, hip, excision.

Sex-Based Differences and Asymmetry in Hip Kinematics During Unilateral Extension From Deep Hip Flexion.

The purpose of this study was to identify side-to-side and sex-based differences in hip kinematics during a unilateral step-up from deep flexion. Twelve (eight men, four women) asymptomatic young adults performed a step ascent motion while synchronized biplane radiographs of the hip were collected at 50 images per second. Femur and pelvis position were determined using a validated volumetric model-based tracking technique that matched digitally reconstructed radiographs created from subject-specific computed tomography (CT) bone models to each pair of synchronized radiographs. Hip kinematics and side-to-side differences were calculated and a linear mixed effects model evaluated sex-based differences. Women were on average 10.2 deg more abducted and 0.2 mm more medially translated than men across the step up motion (p < 0.001). Asymmetry between hips was up to 14.1 ± 12.1 deg in internal rotation and 1.3 ± 1.4 mm in translation. This dataset demonstrates the inherent asymmetry during movements involving unilateral hip extension from deep flexion and may be used provide context for observed kinematics differences following surgery or rehabilitation. Previously reported kinematic differences between total hip arthroplasty and contralateral hips may be well within the natural side-to-side differences that exist in asymptomatic native hips.

[Femoroacetabular impingement in 2024 : concept and diagnosis]. / Conflit fémoro-acétabulaire : concept et diagnostic.

Femoroacetabular impingement (FAI) is a condition that predominantly affects young people between the ages of 20 and 40. It is characterized by hip pain associated with reduced range of movement of the hip joint. If left untreated, FAI leads to osteoarthritis. When first described in the scientific literature in 2003, the concept of FAI was based on two different anatomic features: cam-type deformity and pincer-type deformity. Since that initial description clinical experience and scientific investigation have identified a third pillar of FAI: abnormal femoral torsion. This first article reviews the concept and diagnosis of FAI.

Le conflit fémoro-acétabulaire (CFA) est une pathologie qui touche les sujets jeunes de 20 à 40 ans, entraînant des douleurs associées à une diminution de l'amplitude de mouvement de l'articulation de la hanche. Non traité, le CFA est responsable d'une coxarthrose précoce. Lors de sa première description dans la littérature scientifique en 2003, le concept du CFA était basé sur deux piliers : came et pince. Ces 20 dernières années, de nouvelles connaissances ont émergé, avec notamment la mise en évidence du rôle important de la torsion fémorale, considérée à présent comme le troisième pilier du CFA. Ce premier article fait le point sur le concept et le diagnostic du CFA.

A retrospective study describing the acetabular consequences of Legg- Calve-Perthes disease.

PURPOSE: Legg Calve Perthes disease (LCPD) is a paediatric hip disorder caused by ischemia of the femoral epiphysis, causing femoral head deformity when untreated. This study aims to determine if previously validated pelvic obliquity radiographic parameters, used for assessing acetabular retroversion in developmental dysplasia of the hip, are applicable to patients with LCPD and its prognostic value. METHOD: A retrospective study of patients with Legg Calve Perthes disease was carried out, analysing 4 pelvic parameters: Ilioischial Angle, Obturator Index, Sharp's Angle and Acetabular Depth-Width Ratio (ADR). The differences between healthy and affected hips were studied, and subsequently, it was assessed whether these parameters have prognostic value in the disease outcome. RESULTS: Statistically significant differences have been obtained in the ilioischial angle, obturator index and ADR, between the affected and healthy hip. However, only the Acetabular Depth-Width Ratio showed predictive value for the disease outcome. CONCLUSION: Although this study revealed differences in pelvic parameters between healthy and diseased hips, with only the ADR showing statistical significance in the disease's evolution and prognosis, further studies with larger sample sizes are necessary.

Assessing the reliability of a digital inclinometer app for measuring hip, knee, and ankle proprioception.

Proprioception can be defined as the ability of an individual to detect motion and position of the various joints in their bodies. Current tools for measuring proprioception lack consensus on their accuracy and validity; they also each have their own limitations, and, furthermore, present barriers to use for clinicians. We propose a new and reliable method for evaluating hip, knee, and ankle proprioception by utilizing a digital inclinometer app to measure joint position sense. The digital inclinometer app recorded the active joint position sense error after each of five trials for the hip and knee joint and ten trials for the ankle joint. To quantify the reliability of the digital inclinometer app, single-measurement and average-measurement intra-class correlation coefficients (ICC) along with the associated 95% confidence intervals (95% CI) were calculated for each joint's position sense error across trials. Both the hip (ICC (2,k) = 0.849 (95% CI = [0.783-0.897])) and knee joint (ICC (2,k) = 0.837 (95% CI = [0.750-0.897])) were found to have moderate to good reliability when the middle three of five trials were analyzed. Unlike the hip and knee, moderate to good reliability for ankle proprioception (ICC (2,k) = 0.785 (95% CI = [0.539-0.893])) was only achieved with the middle eight of ten trials. The results of this study indicate that this digital inclinometer app is able to accurately record joint position sense at the hip, knee, and ankle when the appropriate number of trials are collected; thus, allowing this tool and methodology to be considered for use in both clinical and research environments to measure proprioception, and furthermore, quantify proprioceptive deficits.

Recurrent Neural Network Enabled Continuous Motion Estimation of Lower Limb Joints From Incomplete sEMG Signals.

Decoding continuous human motion from surface electromyography (sEMG) in advance is crucial for improving the intelligence of exoskeleton robots. However, incomplete sEMG signals are prevalent on account of unstable data transmission, sensor malfunction, and electrode sheet detachment. These non-ideal factors severely compromise the accuracy of continuous motion recognition and the reliability of clinical applications. To tackle this challenge, this paper develops a multi-task parallel learning framework for continuous motion estimation with incomplete sEMG signals. Concretely, a residual network is incorporated into a recurrent neural network to integrate the information flow of hidden states and reconstruct random and consecutive missing sEMG signals. The attention mechanism is applied for redistributing the distribution of weights. A jointly optimized loss function is devised to enable training the model for simultaneously dealing with signal anomalies/absences and multi-joint continuous motion estimation. The proposed model is implemented for estimating hip, knee, and ankle joint angles of physically competent individuals and patients during diverse exercises. Experimental results indicate that the estimation root-mean-square errors with 60% missing sEMG signals steadily converges to below 5 degrees. Even with multi-channel electrode sheet shedding, our model still demonstrates cutting-edge estimation performance, errors only marginally increase 1 degree.

Research on the Motion Control Strategy of a Lower-Limb Exoskeleton Rehabilitation Robot Using the Twin Delayed Deep Deterministic Policy Gradient Algorithm.

The motion control system of a lower-limb exoskeleton rehabilitation robot (LLERR) is designed to assist patients in lower-limb rehabilitation exercises. This research designed a motion controller for an LLERR-based on the Twin Delayed Deep Deterministic policy gradient (TD3) algorithm to control the lower-limb exoskeleton for gait training in a staircase environment. Commencing with the establishment of a mathematical model of the LLERR, the dynamics during its movement are systematically described. The TD3 algorithm is employed to plan the motion trajectory of the LLERR's right-foot sole, and the target motion curve of the hip (knee) joint is deduced inversely to ensure adherence to human physiological principles during motion execution. The control strategy of the TD3 algorithm ensures that the movement of each joint of the LLERR is consistent with the target motion trajectory. The experimental results indicate that the trajectory tracking errors of the hip (knee) joints are all within 5°, confirming that the LLERR successfully assists patient in completing lower-limb rehabilitation training in a staircase environment. The primary contribution of this study is to propose a non-linear control strategy tailored for the staircase environment, enabling the planning and control of the lower-limb joint motions facilitated by the LLERR.

A Novel Personalized Strategy for Hip Joint Flexion Assistance Based on Human Physiological State.

Soft exosuits have emerged as potent assistive tools for walking support and rehabilitation training. However, most existing soft exosuit systems rely on preset assistance modes, which may not accurately align with individual physiological states and movement requirements, leading to variable user experiences and efficacy. While existing human-in-the-loop (HIL) research predominantly focuses on optimizing metabolic cost and torque difference parameters, there is a notable absence of real-time monitoring methods that closely reflect the human body's physiological state and strategies that dynamically indicate walking efficiency. Motivated by this, we developed a novel personalized power-assist system. This system optimizes the power-assist output of the hip joint by monitoring the user's physiological and motion signals in real time, including heart rate (HR), blood oxygen saturation (SpO2), and inertial measurement unit (IMU) data, to assist hip flexion based on feedback. The findings from a metabolic expenditure trial demonstrate that the innovative soft exosuit, which is based on a Physiological State Monitoring Control (PSMC) system, achieves a reduction of 7.81% in metabolic expenditure during treadmill walking at a speed of 3.5 km/h compared to walking without the assistance of the exosuit. Additionally, during continuous exercise with varying intensities, the metabolic consumption level is reduced by 5.1%, 5.8%, and 8.2% at speeds of 2, 4, and 6 km per hour, respectively. These results support the design of a novel hip flexion-assisting soft exosuit, demonstrating that applying different assistance forces in consideration of different physiological states is a reasonable approach to reducing metabolic consumption.

Do 3-dimensional Spinopelvic Characteristics Normalize After THA? A Prospective, Comparative Study Using Motion Capture Analysis.

BACKGROUND: Spinopelvic stiffness (primarily in the sagittal plane) has been identified as a factor associated with inferior patient-reported outcomes (PROs) and increased dislocation risk after THA. Incorporating preoperative spinopelvic characteristics into surgical planning has been suggested to determine a patient-specific cup orientation that minimizes dislocation risk. Sagittal plane radiographic analysis of static postures indicates that patients exhibit a degree of normalization in their spinopelvic characteristics after THA. It is not yet known whether normalization is also evident during dynamic movement patterns, nor whether it occurs in the coronal and axial planes as well. QUESTIONS/PURPOSES: (1) Does motion capture analysis of sagittal spinopelvic motion provide evidence of normalization after THA? (2) Do changes in coronal and axial plane motion accompany those in the sagittal plane? METHODS: Between April 2019 and February 2020, 25 patients agreed to undergo motion capture movement analysis before THA for the treatment of hip osteoarthritis (OA). Of those, 20 underwent the same assessment between 8 and 31 months after THA. Five patients were excluded because of revision surgery (n = 1), contralateral hip OA (n = 1), and technical issues with a force plate during post-THA assessment (n = 3), leaving a cohort total of 15 (median age [IQR] 65 years [10]; seven male and eight female patients). A convenience sample of nine asymptomatic volunteers, who were free of hip and spinal pathology, was also assessed (median age 51 years [34]; four male and five female patients). Although the patients in the control group were younger than those in the patient group, this set a high bar for our threshold of spinopelvic normalization, reducing the possibility of false positive results. Three-dimensional motion capture was performed to measure spinal, pelvic, and hip motion while participants completed three tasks: seated bend and reach, seated trunk rotation, and gait on a level surface. ROM during each task was assessed and compared between pre- and post-THA conditions and between patients and controls. Statistical parametric mapping (SPM) was used to assess the timing of differences in motion during gait, and spatiotemporal gait parameters were also measured. RESULTS: After THA, patients demonstrated improvements in sagittal spinal (median [IQR] 32° [18°] versus 41° [14°]; difference of medians 9°; p = 0.004), pelvis (25° [21°] versus 30° [8°]; difference of medians 5°; p = 0.02), and hip ROM (21° [18°] versus 27° [10°]; difference of medians 6°; p = 0.02) during seated bend and reach as well in sagittal hip ROM during gait (30° [11°] versus 44° [7°]; difference of medians 14°; p < 0.001) compared with their pre-THA results, and they showed a high degree of normalization overall. These sagittal plane changes were accompanied by post-THA increases in coronal hip ROM (12° [9°] versus 18° [8°]; difference of medians 6°; p = 0.01) during seated trunk rotation, by both coronal (6° [4°] versus 9° [3°]; difference of medians 3°; p = 0.01) and axial (10° [8°] versus 16° [7°]; difference of medians 6°; p = 0.003) spinal ROM, as well as coronal (8° [3°] versus 13° [4°]; difference of medians 5°; p < 0.001) and axial hip ROM (21° [11°] versus 34° [24°]; difference of medians 13°; p = 0.01) during gait compared with before THA. The SPM analysis showed these improvements occurred during the late swing and early stance phases of gait. CONCLUSION: When restricted preoperatively, spinopelvic characteristics during daily tasks show normalization after THA, concurring with previous radiographic findings in the sagittal plane. Thus, spinopelvic characteristics change dynamically, and incorporating them into surgical planning would require predictive models on post-THA improvements to be of use. LEVEL OF EVIDENCE: Level II, prognostic study.

Low Rate of AVN and Complications in Unstable SCFE With Epiphyseal-metaphyseal Discontinuity After Treatment With a Modified Dunn Procedure.

BACKGROUND: The risk of developing avascular necrosis (AVN) in the setting of an unstable slipped capital femoral epiphysis (SCFE) that is undergoing treatment with the modified Dunn procedure is not well understood. In addition, since the Loder classification of unstable is reportedly different than actual intraoperatively observed instability (that is, discontinuity between the femoral head epiphysis and proximal femoral metaphysis), the overall risk of developing AVN, as well as the potential complications of treatment of these patients with the modified Dunn procedure, are unknown. QUESTIONS/PURPOSES: To evaluate the modified Dunn procedure for the treatment of patients with epiphyseal-metaphyseal discontinuity, we asked: (1) What was the survivorship free from AVN at 10 years? (2) What was the survivorship free from subsequent surgery and/or complications at 10 years? (3) What were the clinical and patient-reported outcome scores? METHODS: In a retrospective analysis, we identified 159 patients (159 hips) treated with a modified Dunn procedure for SCFE between 1998 and 2020, of whom 97% (155 of 159) had documentation about intraoperatively observed epiphyseal-metaphyseal stability. Of those, 37% (58 of 155) of patients were documented to have intraoperatively observed epiphyseal-metaphyseal discontinuity and were considered eligible for inclusion, whereas 63% (97 of 155) had documented epiphyseal-metaphyseal stability and were excluded. No patients were lost to follow-up before the 2-year minimum. All patients were assessed for survival, but 7% (4 of 58) did not fill out our outcomes score questionnaire. This resulted in 93% (54 of 58) of patients who were available for outcome score assessment. Additionally, 50% (29 of 58) of patients had not been seen within the last 5 years; they are included, but we note that there is uncertainty about their status. The median (range) age at surgery was 13 years (10 to 16), and the sex ratio was 60% (35 of 58) male and 40% (23 of 58) female patients. Sixty-four percent (37 of 58) of patients were classified as acute-on-chronic, and 17% (10 of 58) of patients were classified as acute. Forty-seven percent (27 of 58) of patients presented with severe slips and 43% (25 of 58) of patients with moderate slips based on radiographic classification. All patients underwent surgical hip dislocation with the modified Dunn procedure to correct the slip deformity and provide stabilization. Complications and reoperations were assessed from a review of electronic medical records, and a Kaplan-Meier estimator was used to estimate survivorship free from complications and reoperations at 10 years. Clinical examination results and questionnaire responses were evaluated at minimum 2-year follow-up. RESULTS: Kaplan-Meier survivorship free from AVN was 93% (95% CI 87% to 100%) at 10 years. Survivorship free from any reoperation was 75% (95% CI 64% to 88%) at 10 years. In addition, survivorship free from complications, defined as development of AVN, reoperation, or a Sink Grade II complication or higher, was 57% (95% CI 45% to 73%) at 10 years. The median (range) Merle D'Aubigne Postel score was 18 (14 to 18) for the patients who did not develop AVN, and 12 (6 to 16) for the four patients who developed AVN (p < 0.001). The median modified Harris hip score was 100 (74 to 100) in the non-AVN cohort and 65 (37 to 82) in the AVN cohort (p = 0.001). Median HOOS total score was 95 (50 to 100) in the non-AVN cohort and 53 (40 to 82) in the AVN cohort (p = 0.002). CONCLUSION: Although the modified Dunn procedure is technically challenging, this study shows that in experienced hands, patients with who have demonstrated epiphyseal-metaphyseal discontinuity can be treated with a low risk of AVN and subsequent surgery. Referral of these patients to specialists who have substantial expertise in this procedure is recommended to improve patient outcomes. Prospective, long-term observational studies will help us identify these high-risk patients preoperatively and determine the long-term success of this procedure. LEVEL OF EVIDENCE: Level IV, therapeutic study.

An arm swing enhances the proximal-to-distal delay in joint extension during a countermovement jump.

An abundance of degrees of freedom (DOF) exist when executing a countermovement jump (CMJ). This research aims to simplify the understanding of this complex system by comparing jump performance and independent functional DOF (fDOF) present in CMJs without (CMJNoArms) and with (CMJArms) an arm swing. Principal component analysis was used on 39 muscle forces and 15 3-dimensional joint contact forces obtained from kinematic and kinetic data, analyzed in FreeBody (a segment-based musculoskeletal model). Jump performance was greater in CMJArms with the increased ground contact time resulting in higher external (p = 0.012), hip (p < 0.001) and ankle (p = 0.009) vertical impulses, and slower hip extension enhancing the proximal-to-distal joint extension strategy. This allowed the hip muscles to generate higher forces and greater time-normalized hip vertical impulse (p = 0.006). Three fDOF were found for the muscle forces and 3-dimensional joint contact forces during CMJNoArms, while four fDOF were present for CMJArms. This suggests that the underlying anatomy provides mechanical constraints during a CMJ, reducing the demand on the control system. The additional fDOF present in CMJArms suggests that the arms are not mechanically coupled with the lower extremity, resulting in additional variation within individual motor strategies.

[Systematic evaluation of the painful hip]. / Evaluación sistemática de la cadera dolorosa.

The painful hip has been a topic of study that has evolved from the beginning of the last century to the present. The clinical approach is complex, and requires a systematization process associated with good questioning, clinical maneuvers with their corresponding interpretation, and complementary imaging studies. The understanding of hip pathology, especially in young adults, is highly simplified and sometimes underdiagnosed, therefore, not treated in a timely manner. The prevalence of painful hip is more common in males (49 to 55%) than in females (25 to 28%), and the causes may vary according to demographic characteristics and the history of each patient. Bryan Kelly, made a topographic and anatomical description of the approach to the painful hip according to the theory or system of the layers: I. Osteochondral layer; II. Inert layer; III. Contractile layer; and IV. Neuro-mechanical layer. This system helps us understand the anatomical site of pain and its clinicopathological correlation. The semiological approach to hip pain is the fundamental pillar for differential diagnosis. We can divide it according to its topography into anterior, lateral and posterior, as well as according to its chronology and characteristics. The physical examination should be carried out systematically, starting from a generalized inspection of gait and posture to the evaluation of specific signs for alterations in each layer, which evoke pain with specific postures and ranges of mobility, or weakness and alterations in the arc of mobility of the joint. Image evaluation is initially recommended with radiographic projections that evaluate different planes, both coronal, sagittal and axial, complemented with panoramic views, and eventually dynamic sagittal ones if necessary. Requesting specific studies such as tomography to evaluate bone structure and reserve, or simple MRI when there is suspicion of soft tissue affection, or failing that, arthroresonance for joint pathology, will depend on the clinical symptoms and radiographic findings.

La cadera dolorosa ha sido un tema de estudio que ha evolucionado desde principios del siglo pasado hasta la actualidad. El abordaje clínico es complejo y exige un proceso de sistematización asociado a un buen interrogatorio, maniobras clínicas con su interpretación correspondiente y estudios de imagen complementarios. El entendimiento de la patología de cadera, sobre todo en adulto joven, es altamente simplificado y en ocasiones infradiagnosticado, por lo tanto, no tratado en tiempo y forma. La prevalencia de cadera dolorosa es más frecuente en el sexo masculino (49 a 55%) que en el femenino (25 a 28%), y las causas pueden variar de acuerdo a características demográficas y a los antecedentes de cada paciente. Bryan Kelly realizó una descripción topográfica y anatómica del abordaje de la cadera dolorosa de acuerdo con la teoría o sistema de las capas: I. Capa osteocondral; II. Capa inerte; III. Capa contráctil; y IV. Capa neuromecánica. Este sistema nos ayuda a entender el sitio anatómico del dolor y su correlación clínico-patológica. El abordaje semiológico del dolor de cadera es el pilar fundamental para el diagnóstico diferencial. Podemos dividirlo de acuerdo con su topografía en anterior, lateral y posterior, así como de acuerdo a su cronología y características. La exploración física debe realizarse de manera sistemática, iniciando desde inspección generalizada, de la marcha y postura hasta la evaluación de signos específicos para alteraciones en cada capa, los cuales evocan dolor con posturas y arcos de movilidad específicos, o bien debilidad y alteraciones en el arco de movilidad de la articulación. La evaluación por imagen se recomienda inicialmente con proyecciones radiográficas que evaluen diferentes planos, tanto coronal, sagital y axial, complementado con panorámicas, y eventualmente sagitales dinámicas de ser necesarios. Solicitar estudios específicos como tomografía para evaluar estructura y reserva ósea, o bien, resonancia simple cuando hay sospecha de afección a tejidos blandos, o en su defecto, artrorresonancia para patología articular, dependerá de la clínica y los hallazgos radiográficos.

Managing Pediatric Hip Pain Patients with Precision.

ABSTRACT: Pediatric hip pain can have orthopedic, infectious, inflammatory, neoplastic, or nonmusculoskeletal etiologies. Organizing the differential diagnosis by symptom chronicity and a determination of intraarticular versus extraarticular pain, as well as the age at pain onset, can be helpful to hone in on the cause. Clinicians should consider plain radiographs in cases of acute trauma, with concern for bony pathology, or in patients with unexplained limp or hip pain, with musculoskeletal ultrasound and magnetic resonance imaging used as advanced imaging when indicated. Relative rest with subsequent strengthening and stretching should be prescribed in nonoperative conditions, though several pediatric hip pain diagnoses require orthopedic or other specialty referral for definitive treatment. This article is a comprehensive review of hip pain etiologies in the pediatric population.

Previous lumbar spine fusion increases the risk of dislocation following total hip arthroplasty in patients with hip-spine syndrome: a systematic review and meta-analysis.

BACKGROUND: With life expectancy on the rise, there has been an increase in patients with concomitant degenerative hip and spine pathology, defined as hip-spine syndrome (HSS). Patients affected by HSS may require both total hip arthroplasty (THA) and lumbar spinal fusion (LSF), although there is a paucity of data regarding how the sequential timing of these procedures may influence clinical outcomes. This study aims to compare complications and spinopelvic parameters in patients with HSS who underwent either LSF first or THA first. METHODS: A systematic search of PubMed and Scopus was conducted for randomized and nonrandomized studies investigating complications and spinopelvic parameters in patients with HSS who had undergone THA and LSF. The Methodological Index for Non-Randomized Studies (MINORS) tool was utilized to assess the risk of bias in included studies. Relevant outcomes were pooled for meta-analysis. RESULTS: Eleven articles were included in this study. There was a significantly higher THA dislocation rate in patients who had undergone LSF first compared to those who had THA first (OR: 3.17, 95% CI 1.23-8.15, P = 0.02). No significant difference was found in terms of THA aseptic loosening (OR: 0.86; 95% CI 0.32-2.32, p = 0.77) and revision rate (OR: 1.18, 95% CI: 0.53-2.62) between these two groups. Individuals who received THA only showed a significantly lower risk of hip dislocation (OR: 0.14, 95% CI: 0.08-0.25, P < 0.00001) and THA revision (OR: 0.22, 95% CI: 0.14-0.36, P < 0.00001) compared to patients with a previous LSF. CONCLUSIONS: In HSS patients who underwent both LSF and THA, those who received LSF first displayed an increased risk of hip dislocation after subsequent THA. Additionally, the relative risks of dislocation and revision rate appeared significantly lower in patients who had undergone THA only when compared to THA patients with a history of previous LSF. Due to the impact of LSF on spinopelvic biomechanics, caution must be exercised when performing THA in individuals with instrumented spines. PROSPERO ID: CRD42023412447. LEVEL OF EVIDENCE: LL.