Modified osteochondral autograft transplantation for steroid-induced osteonecrosis of femoral head in idiopathic thrombocytopenic purpura: a case report and literature.

Osteochondral autograft transplantation (OAT) has been commonly applied in the knee and ankle while the technique has not yet been a popularity in the femoral head. In this article, we present a 28-year-old female patient, who has a history of 1-year-use of glucocorticoid in the treatment of idiopathic thrombocytopenic purpura, with steroid-induced osteonecrosis of the femoral head (SONFH). She underwent surgical hip dislocation, osteochondroplasty, OAT, and internal fixation. Her Harris Hip Score improved from 64 to 82 in 36 months to follow-up. The case is valuable considering that a single, instead of several, 1.5 cm autograft was harvested from the non-bearing part of the same femoral head. This modification dispensed with the need of surgery for harvesting autograft from knee or ankle and reduced the structural vulnerability brought by the multihole donor part of the femoral head.

Early Prosthetic Hip Dislocation: Does the Timing of the Dislocation Matter?

BACKGROUND: Early dislocation following total hip arthroplasty (THA) is a common reason for revision. The purpose of this study was to determine if the acuity of the dislocation episode affects the risk of revision surgery. METHODS: A retrospective review of a national, all-payer administrative database comprised of claims from 2010 to 2020 was used to identify patients who had a prosthetic hip dislocation at various postoperative time intervals (0 to 7, 7 to 30, 30 to 60, and 60 to 90 days). Of the 45,352 primary unilateral THA patients who had sufficient follow-up, there were 2,878 dislocations within 90 days. Dislocators were matched 1:1 based on age, sex, and a comorbidity index with a control group (no dislocation). Demographics, surgical indications, comorbidities, ten-year revision rates, and complications were compared among cohorts. Multivariable logistic regression analysis was performed to identify risk factors for revision THA following early dislocation. RESULTS: Among matched cohorts, dislocation at any time interval was associated with significantly increased odds of subsequent 10-years revision (OR [odds ratio] = 25.60 to 33.4, P < .001). Acute dislocators within 7 days did not have an increased risk of all cause revisions at 10 years relative to other early dislocators. Revision for indication of instability decreased with time to first dislocation (<7 days: 85.7% versus 60 to 90 days: 53.9%). Primary diagnoses of posttraumatic arthritis (OR = 2.53 [1.84 to 3.49], P < .001), hip fracture (OR = 3.8 [2.53 to 5.72], P < .001), and osteonecrosis (OR = 1.75 [1.12 to 2.73], P = .010) were most commonly associated with revision surgery after an early dislocation. CONCLUSIONS: Dislocation within 90 days of THA is associated with increased odds of subsequent revision. Early dislocation within 7 days of surgery has similar all cause revision-free survivorship, but an increased risk of a subsequent revision for instability when compared to patients who dislocated within 7 to 90 days.

Pelvic flexion/extension and its impact on functional acetabular alignment and stability following total hip replacement.

PURPOSE: Dislocation following total hip arthroplasty (THA) remains a significant clinical problem and can occur even with optimal implant alignment. We hypothesized that different patterns of pelvic flexion/extension (PFE) during daily activities may influence acetabular alignment and contribute to impingement and instability following THA. Recently, there has been an increased interest in spinopelvic alignment and its impact on THA. Therefore, this study aimed to identify different patterns of PFE that could be predictive of instability following THA. METHODS: A range of motion (ROM) simulator was used to demonstrate the effects of different patterns of PFE on ROM and impingement. The findings were applied to PFE measurements obtained from 84 patients in standing and sitting positions. RESULTS: Three different categories of PFE were identified: normal, hypermobile, and stiff. ROM simulator revealed that changes in PFE had affected ROM and impingement significantly. Patients in the stiff pelvis category, even with "optimal" implant alignment, were more susceptible to implant impingement. CONCLUSIONS: The different patterns of PFE during daily activities could affect acetabular alignment and stability following THA. We propose a classification system that can identify different types of PFE and predict their effects on the stability of prostheses following THA. Hence, we believe that patients with unfavorable PFE may require modified cup alignment.

Extended offset stems are infrequently required in anterior approach total hip arthroplasty and low usage does not compromise stability.

INTRODUCTION: Extended offset (EO) stems are commonly used in posterior approach (PA) total hip arthroplasty (THA), but usage rates and complications are not well studied with anterior approach (AA) THA. This study evaluated usage rates, radiographic outcomes and complications following AA THA between patients receiving EO stems and a matched cohort receiving standard offset (SO) stems. MATERIALS AND METHODS: This retrospective review evaluated 1515 consecutive AA THA performed between 2014 and 2021. The recent 100 EO were included in radiographic and complication analysis and were matched to 100 SO stems based on stem size, procedure (unilateral/bilateral), sex, body mass index (BMI), and age. Data collection included patient demographics; pre- and postoperative radiographic measurements of leg length difference (LLD) and global hip offset difference (GHOD); and complications within 1 year. Independent t-tests and Chi-squared analyses compared EO and SO groups. RESULTS: EO was utilized in 8% of all AA THA. Despite matching procedures, the distribution of racial groups was different between EO and SO groups, respectively: Caucasian (75% vs. 43%), Asian (12% vs. 35%), Native Hawaiian/Pacific Islander (NHPI) (9% vs. 13%), and other (4% vs. 9%) (p < 0.001). No fractures, dislocations, or revisions occurred within 1 year after surgery in either group. One deep infection was noted in the SO group. The proportions of patients following surgery who had a GHOD < 6 mm (76% vs. 82%; p = 0.193) and LLD < 6 mm (81% vs. 86%; p = 0.223) were not significantly different between EO and SO groups, respectively. CONCLUSIONS: Prioritizing hip symmetry over stability results in a high proportion of patients achieving hip symmetry without high usage of EO stems in AA THA. Furthermore, low use of EO stems did not result in increased dislocations. Due to racial anatomical differences, Caucasian patients required EO stems to achieve hip symmetry more frequently than Asian and NHPI patients.

Causes of late-presenting developmental dislocation of the hip beyond 12 months of age: A pilot study.

Background & objectives: Developmental dysplasia of the hip (DDH), when detected early, can usually be managed effectively by simple methods. A delayed diagnosis often makes it a complex condition to treat. Late presentation of DDH is fairly common in developing countries, and there is scarcity of literature regarding the epidemiology and reason for late presentation. Through this study, we attempted to identify the reasons for late presentation of DDH in children more than 12 months of age. Methods: Fifty four children with typical DDH and frank dislocation of hip in whom treatment was delayed for 12 months or more were included. Parents were interviewed with a pre-structured questionnaire and data were collected for analysis with Microsoft Excel 2016 and SPSS version 26. Results: Diagnostic delay was the most common reason for late presentation and was observed in 52 children (96.2%). The mean age at diagnosis was 24.7 months. The mean age at treatment was 37.3 months with a mean delay of 12.5 months from diagnosis and 22.1 months from initial suspicion. Physician-related factors contributed 55.3 per cent, while family and social issues accounted for 44.7 per cent of overall reasons for diagnostic and treatment delays. Interpretation & conclusions: Late presentation of DDH in walking age is common. Physician- and family-related factors accounted for most of these cases. Failure or inadequate hip screening at birth by the attending physician is a common reason for late diagnosis. The family members were unaware about the disorder and developed suspicion once child started walking with an abnormal gait.

The International Hip Dysplasia Institute (IHDI) classification is more informative than the Tönnis classification.

BACKGROUND: A new, supposedly more reproducible radiographic classification, set to replace the Tönnis classification of hip dislocations, was proposed in 2015: the International Hip Dysplasia Institute (IHDI) classification. PURPOSE: To compare the IHDI classification with the Tönnis classification when evaluating the severity of hip dislocations as well as their respective inter- and intra-observer reliability. MATERIAL AND METHODS: Since January 2000, Swedish-born children with a hip dislocation were prospectively registered. From this registry, radiographs of 97 hips in 79 patients (91% girls; median age = 7 months), born in 2000-2009, were analyzed. Two observers, one consultant and one resident, classified each hip both by IHDI and Tönnis twice. RESULTS: The IHDI classification had a more even distribution of grades with the majority in grade 2-3. The Tönnis classification graded the majority (77%) of the patients as grade 2 and equally among the other grades. There was moderate inter-observer agreement using both methods calculated with Kappa, 0.61 (95% confidence interval [CI] = 0.44-0.79) for Tönnis and 0.62 (95% CI = 0.49-0.74) for IHDI. The resident calculated Tönnis with weak intra-observer reliability of 0.57 (95% CI = 0.40-0.74) compared to high intra-observer reliability of 0.86 (95% CI = 0.74-0.98) for the consultant. Both observers graded IHDI with high intra-observer reliability. CONCLUSION: IHDI is more discriminative than the Tönnis classification when evaluating the severity of a hip dislocation in infants.

Prosthetic femoral interposition arthroplasty with adult humeral implant, for children with cerebral palsy and symptomatic hips.

BACKGROUND: Immobile patients with cerebral palsy can suffer with painful dislocated hips. Decision-making and surgical management can prove challenging in this cohort of patients, with hips that cannot be reconstructed. METHODS: We conduced a retrospective chart review of all patients who underwent prosthetic femoral interposition arthroplasty (PFIA) by two surgeons from 2013 to 2021, for unreconstructable hips. We compared pain and range of motion in preoperative period to the postoperative period. Caregiver reported outcomes were used to assess satisfaction post operatively. During the follow up, radiographs of the PFIA were obtained to assess for proximal migration, heterotopic ossification and loosening of implants. RESULTS: Eleven index surgeries, which met the inclusion criteria, were included in this study. These were performed in eleven patients with an average follow up of 45 months. Regarding pain and range of motion post-operatively an excellent or good result was seen in nine cases. Two patients were classified as having a fair result with none having a poor result. Most caregivers reported being satisfied or very satisfied with the post-operative outcomes. CONCLUSION: A prescriptive operative solution to the painful dislocated hip in children with spastic cerebral palsy remains elusive. In this study, we have demonstrated both clinically and radiologically satisfactory results post proximal femoral interposition arthroplasty, for those patients with unreconstructable hips. Patient caregiver reported outcomes, show that the majority of caregivers were satisfied or very satisfied with the outcome of the surgery.

Clinical and radiological outcomes following surgical hip dislocation for paediatric hip pathologies, a prospective cohort study.

BACKGROUND: Surgical Hip Dislocation (SHD) is a powerful tool in the armamentarium of any surgeon treating conditions affecting the hips of children presenting with sequelae of a number of common conditions including Legg-CalvéPerthes disease (LCPD) and slipped capital femoral epiphysis (SCFE). Risks associated with the procedure are well described. We investigated to assess if SHD is associated with significant surgical risk and if it improved clinical outcomes for patients. METHODS: We conducted a prospective cohort study. We reviewed 18 (11 males and 7 females; mean age 13.7 years (6-17) with symptomatic hip pathology, secondary to femoroacetabular impingement (FAI) between 2017 and 2021. All patients underwent a surgical hip dislocation approach and femoral head-neck osteochondroplasty, Head Split osteotomy or both. Clinical improvement was assessed using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) index. The minimum follow-up was 6 months (mean, 22 months; range, 6-42 months). RESULTS: WOMAC scores improved at final follow-up from 10 to 3 for pain, 33 to 10 for function, and 4 to 2 for the stiffness subscales. All radiographic measures improved significantly of the postoperative X-rays. No patients developed osteonecrosis, implant failure, deep infection, or nonunion. CONCLUSION: Surgical Hip Dislocation, in the short term, we found improvement in WOMAC scores and radiographic indices with a low complication rate.

A Meta-Analysis of the Incidence and Temporal Trends of Postoperative Dislocation in Revision Total Hip Arthroplasty Utilizing Constrained Acetabular Components or Dual Mobility Implants.

BACKGROUND: The incidence of dislocation after revision total hip arthroplasty (rTHA) is reported to be up to 25% and remains a common source of failure. Constrained acetabular components and dual mobility implants are two implant classes being utilized to alleviate this burden in patients who have recurrent instability or major intraoperative instability. This meta-analysis evaluated the incidence and temporal trends of dislocation after implantation with constrained acetabular components and dual mobility implants in rTHA. METHODS: Longitudinal studies reporting dislocation after the use of constrained acetabular components or dual mobility implants in rTHA were sought from Medline and Embase to October 2022. Secondary outcomes included re-revision surgery for dislocation and all causes. A total of 75 relevant citations were identified comprising 36 datasets of 3,784 constrained acetabular components and 47 datasets of 10,216 dual mobility implants. RESULTS: For constrained acetabular components, the pooled incidence of dislocation was 9% (95% confidence interval: 7.2, 11.7) (range 0.0%-35.3%) over a weighted mean follow-up of 6 years, in contrast to 3% (95% confidence interval: 2.2, 4.4) (range 0.0%-21.4%) over 5 years for dual mobility implants. Re-revision rates for dislocation after using constrained acetabular components were around 9%, in contrast to 2% for dual mobility implants. Re-revision rates for all causes after using constrained acetabular components were around 19%, in contrast to 8% for dual mobility implants. CONCLUSION: Dual mobility implants in the context of rTHA demonstrate lower incidences of dislocation (3% versus 9%), re-revision for dislocation (2% versus 9%), and rer-evision for any cause (8% versus 19%) in contrast to constrained acetabular components. This must be considered by surgeons when implanting such devices, often selected to treat instability.

Prosthetic Hip Dislocations in Direct Anterior Versus Posterior Approach in Patients With Instrumented Lumbar Fusion.

BACKGROUND: Instrumented posterior lumbar spinal fusion (IPLSF) has been demonstrated to contribute to instability following total hip arthroplasty (THA). It is unclear whether a supine direct anterior (DA) approach reduces the risk of instability. METHODS: A retrospective review of 1,773 patients who underwent THA through either a DA approach or a posterior approach at our institution over a 7-year period was performed. Radiographic and chart reviews were then used to identify our primary group of interest comprised of 111 patients with previous IPLSF. Radiographic review, chart review, and phone survey was performed. Dislocation rates in each approach group were then compared within this cohort of patients with IPLSF. RESULTS: Within the group of patients with IPLSF, 33.3% (n = 37) received a DA approach while 66.6% (n = 74) received a posterior approach. None of the 9 total dislocations in the DA group had IPLSF, whereas 4 of the 16 total dislocations in the posterior approach group had IPLSF (P = .78). When examining the larger group of patients, including those without IPLSF, patients undergoing a DA approach had a lower BMI and were likely have a smaller head size implanted (P < .001 for both). Using Fischer's exact test, fusion was associated with dislocation in the posterior approach group (P < .01), whereas fusion was not associated with dislocation in the anterior approach group (P = 1.0). CONCLUSIONS: While there was no significant difference in dislocation rates between posterior and anterior approach groups, in patients with IPLSF, the anterior approach had a lower percentage of dislocation events compared to the posterior approach.

How Does Surgical Approach Affect Characteristics of Dislocation After Primary Total Hip Arthroplasty?

BACKGROUND: Concerns have been voiced regarding how surgical approach impacts risk of dislocation after total hip arthroplasty (THA). This study investigated how surgical approach impacts rate, direction, and timing of dislocations following THA. METHODS: We conducted a retrospective review of 13,335 primary THAs from 2011 to 2020 and identified 118 patients with prosthetic hip dislocation. Patients were stratified into cohorts by surgical approach used during primary THA. Patient demographics, index THA acetabular cup positioning, number, direction, timing of dislocations, and subsequent revisions were collected. RESULTS: Dislocation rate differed significantly between posterior approach (PA), direct anterior approach (DAA), and laterally-based approach (LA) (1.1 versus 0.7% versus 0.5%, P = .026). Rate of hips dislocating anteriorly was lowest in the PA group (19.2%) compared to LA (50.0%) and DAA groups (38.2%, P = .044). There was no difference in rate of hips dislocating posteriorly (P = .159) or multidirectional (P = .508) instability; notably 58.8% of dislocations in the DAA cohort occurred posteriorly. There were no differences in dislocation timing or revision rate. Acetabular anteversion was highest in the PA cohort compared to DAA and LA (21.5 versus 19.2 versus 11.7 degrees, P = .049). CONCLUSION: After THA, patients in the PA group had a slightly higher dislocation rate compared to the DAA and LA groups. The PA group had a lower rate of anterior dislocation and nearly 60% of DAA dislocations occurred posteriorly. However, with no differences in other parameters including revision rates or timing, our data suggests surgical approach may impact dislocation characteristics to a lesser degree than previous studies have suggested.

Postsurgical Analysis of Gait, Radiological, and Functional Outcomes in Children with Developmental Dysplasia of the Hip.

BACKGROUND: Children undergoing DDH correction surgery may experience gait abnormalities following soft tissue releases and bony procedures. The purpose of this study was to compare the residual gait changes, radiological outcomes, and functional outcomes in children who underwent DDH surgery with those in healthy controls. METHODS: Inertial motion sensors were used to record the gait of 14 children with DDH and 14 healthy children. Pelvic X-ray was performed to determine the Severin classification and the presence of femoral head osteonecrosis (Bucholz-Odgen classification). For functional evaluation, the Children's Hospital Oakland Hip Evaluation Scale (CHOHES) was used. RESULTS: There was no difference in spatial parameters between the two groups. In terms of temporal parameters, the DDH-affected limbs had a shorter stance phase (p < 0.001) and a longer swing phase (p < 0.001) than the control group. The kinematic study showed that the affected limb group had smaller hip adduction angle (p = 0.002) and increased internal rotation (p = 0.006) with reduced upward pelvic tilt (p = 0.020). Osteonecrosis was graded II, III, and IV in five, three, and one patients, respectively. Five patients had no AVN changes. The Severin classification was grade I, II, and III for six, three, and five patients, respectively. Most patients had good functional outcomes on the CHOHES, with a mean total score of 96.64 ± 5.719. Multivariate regression analysis revealed that weight, height, and femoral osteotomy were independent predictors for gait, radiological and functional outcome. CONCLUSION: Despite good functional scores overall, some children had poor radiological outcomes and gait abnormalities. Our results identified the risk factors for poor outcomes, and we recommend specified rehabilitative strategies for long-term management.

The evolution of surgical hip dislocation utilization and indications over the past two decades: a scoping review.

PURPOSE: To assess the evolution of surgical hip dislocation (SHD) utilization over the past 20 years, concentrating mainly on the patients' population (adults vs. paediatric), the hip conditions treated using this approach, and reporting on complications of this procedure. METHODS: This scoping review was conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines. A PubMed database search was performed using specific search terms for articles related to SHD published between January 2001 and November 2022. RESULTS: Initial search revealed 321 articles, of which 160 published in 66 journals from 28 countries were eligible for final analysis. The number of publications increased by 10.2 folds comparing the period from 2001 to 2005 with 2018 to 2022. USA and Switzerland contributed to more than 50% of the publications. Case series studies represented the majority of publications (65.6%). Articles including adult patients represented 73.1% of the publications while 10% were on paediatric patients; however, there was 14 folds increase in publications on paediatric patients comparing the first with the last five years. Managing non-traumatic conditions was reported in 77.5% of the articles, while traumatic conditions in 21.9%. Femoroacetabular impingement (FAI) was the most treated non-traumatic condition reported in 53 (33.1%) articles. In contrast, femoral head fractures (FHF) were the most treated traumatic condition, which was reported in 13 articles. CONCLUSION: The publications on SHD and its usage for managing traumatic and non-traumatic hip conditions showed an increasing trend over the past two decades from worldwide countries. Its use in adult patients is well established, and its utilization in treating paediatric hip conditions is becoming more popular.

Hip arthroplasty dislocation risk calculator: evaluation of one million primary implants and twenty-five thousand dislocations with deep learning artificial intelligence in a systematic review of reviews.

PURPOSE: This paper aims to provide an overview of the possibility regarding the artificial intelligence application in orthopaedics to predict dislocation with a calculator according to the type of implant (hemiarthroplasty, standard total hip arthroplasty, dual mobility, constrained cups) after primary arthroplasty. MATERIAL AND METHODS: Among 75 results for primary arthroplasties, 26 articles were reviews on dislocation after hemiarthroplasty, 40 after standard total hip arthroplasty, seven about primary dual-mobility arthroplasty (DM THA), and two reviews about constrained implants. Although our search method for systematic reviews covers ten years (2012-2022), none for dual mobility was published before 2016, showing a recent explosion of original articles on this subject. A total of 1,069,565 implants and 26,488 dislocations in primary arthroplasties are included in these 75 reviews. We used a supervised learning model in which models assign objects to groups as input and artificial neural network (ANN) with nodes, hidden layers, and output layers. We considered only four implant types as the input layer. We considered the patient's factors (indication for THA, demographics, spine surgery, and neurologic disease) as the second input values (hidden layer). We considered the implant position as the third input (hidden layer) property including head size, combined anteversion, or spinopelvic alignment. Surgery-related factors, approach, capsule repair, etc. were the fourth input values (hidden layer). The output was a post-operative dislocation or not within three months. RESULTS: The accuracy for predicting dislocation with this systematic review was 95%. Dislocation risk, based on the type of implant, was wide-ranging, from 0 to 3.9% (mean 0.31%) for the 3045 DM THA, from 0.2 to 1.2% (overall 0.91%) for the 457 constrained liners, from 1.76 to 4.2% (mean 2.1%) for 895,734 conventional total hip arthroplasties, and from 0.76 to 12.2% (mean 4.5%) for 170,329 hemiarthroplasties. In the conventional THA group, many factors increase the risk of dislocation according to the calculator, and only a few (big head, anterior approach) decrease the risk, but not very significantly. In the hemiarthroplasty group, many factors can increase the risk of dislocation until 30%, but none could decrease the risk. According to the calculator, the DM THA and the constrained liner markedly decreased the risk and were not affected by implant position, spine surgery, and spinopelvic position. CONCLUSION: To our knowledge, this study is the first to yield an implant-specific dislocation risk calculator that incorporates the patient's comorbidities, the position of components, and surgery factors affecting instability risk.

Risk Factors for Dislocation following Total Hip Arthroplasty in Developmental Dysplasia of the Hip: A Systematic Review and Meta-Analysis.

PURPOSE: This systematic review and meta-analysis aimed to identify risk factors of dislocation after total hip arthroplasty (THA) in patients with developmental dysplasia of the hip (DDH). METHODS: A systematic literature review was performed on 18th August 2022 using Medline, Embase, Scopus, Web of Science electronic databases, and a manual search. The study was conducted according to the PRISMA guidelines and registered with PROSPERO. Statistical analysis includes assessment of heterogeneity and data synthesis using RevMan 5.4. RESULTS: Review of five studies including 2865 patients and 116 dislocated hips found that lower body mass index (BMI) (SMD = 0.22, p = 0.04, I2 = 0%), Crowe classification type IV versus I, II, and III (OR = 2.70, p = 0.004, I2 = 51%), higher cup inclination (SMD = 0.39 p = 0.0007, I2 = 0%), femoral head size < 28 mm (OR = 5.07, p = 0.003, I2 = 71%), lateral surgical approach (OR = 1.96, p = 0.02, I2 = 0%), and postoperative infection (OR = 6.26, p < 0.0001, I2 = 0%) were significant risk factors. However, age, gender, cup anteversion, femoral osteotomy, vertical (V-COR) centre of rotation, intraoperative fracture, preoperative and postoperative leg length discrepancy (LLD) and previous hip surgery were not found to be significant risk factors. CONCLUSION: This study underscores importance of these risk factors in THA planning for DDH patients to reduce dislocation risk. Further research needed to understand mechanisms.

Prognostic factors for failed Pavlik harness treatment in infants with developmental dysplasia of the hip: a retrospective cohort study.

PURPOSE: Pavlik harness treatment is the most common treatment in newborns diagnosed with developmental dysplasia of the hip (DDH). The success rates and predictors for failure have been debated over the last decade. In this study, we explored our treatment failure rate and potential prognostic factors that could predict the failure of Pavlik harness (PH) treatment in patients with DDH. METHODS: Two hundred and sixty-five patients were treated with PH based on the Graf hip types of classification. Age, gender, first born status, family history, foot deformity, plagiocephaly, breech presentation, hip abduction, hip stability, Graf hip type, Galeazzi sign, bilateralism, and femoral nerve palsy were tested as predictors for failure in multivariate logistic regression mode. Success and failure were determined by the normalization of the hip based on the Graf hip classification. RESULTS: The failure rate of patients treated with Pavlik harness was 16.6% which is within the reported range of failure rate. The mean age of patients who were successfully treated was 6.73 weeks in comparison to 8.84 weeks for those who failed. Age, plagiocephaly, hip instability, Graf classification, and the development of femoral nerve palsy were found to be predictors for failure of PH treatment upon univariate analysis only. However, only the presence of Galeazzi sign, hip instability, high grades of Graf hip classification, and the development of femoral nerve palsy proved to be independent predictors for failed PH treatment upon multivariate logistic regression analysis. CONCLUSIONS: Pavlik harness treatment is a successful treatment with an average success of 83.4%. Several independent predictors for failure of PH treatment have been identified. These include a positive Galeazzi sign, a frankly dislocated hip, Graf types III and IV, and the development of femoral nerve palsy.

Hospital transfer and delayed reduction of traumatic hip dislocations.

INTRODUCTION: Native hip dislocations are high energy injuries that cause substantial patient morbidity. Expedient reduction has been demonstrated to improve patient outcomes. The objective of our study was to compare complication rates in patients with native hip dislocations who presented directly to a level-one trauma center with those transferred from an outside hospital (OSH). Our hypothesis was that those transferred from an OSH would experience a delay in reduction and subsequently would experience higher rates of avascular necrosis (AVN), post-traumatic arthritis (PTA), and need for secondary surgery. MATERIAL AND METHODS: We conducted a retrospective chart review of all native hip dislocations from our level-one trauma center between January 2007 and December 2020. The initial query resulted 628 patients which was refined to 90 patients after excluding patients for incorrect diagnosis code or less than 6 months of follow-up. Our primary outcome was the development of AVN, PTA, and need for secondary surgery. Time from injury to reduction was recorded for all patients included. RESULTS: For every one hour of delay in time to reduction, there was a 3.4% increase in the risk of developing AVN (p = 0.004) and a 4.3% increase in risk for developing PTA (p = 0.01). The risk of requiring a secondary surgery increased 4.6% for each hour of delay in reduction (p = 0.03). The average time to reduction of transferred patients was higher compared to those who presented directly to our center (13.8 h vs 5.7 h); however, transfer status was not found to be an independent risk factor for the measured outcomes. CONCLUSIONS: Transfer status is not an independent risk factor for the development of AVN, PTA, or the need for a secondary surgery. However, transferred patients did experience an average delay of 8 h in time to reduction compared to those who presented directly to a trauma center. Of the 27 patients with a reduction delay greater than 12 h, 26 (96%) were transferred.

What is the rate of successful closed reduction of dislocated dual mobility cups following complex revision hip arthroplasty?

PURPOSE: The aim of this study was to assess the difference in success rates of closed reduction in septic and aseptic revision total hip arthroplasty (THA) performed with a dual mobility (DM) implant. Our objective was to answer the following questions: (1) Is there a difference in success rates of closed reduction between septic and aseptic revision THA with a DM implant? (2) Is closed or open reduction more successful in preventing re-dislocation? METHODS: Between January 2009 and October 2021, 924 revisions were performed with a DM implant. All patients presenting to our institution with a dislocation following septic or aseptic revision THA using a cemented DM cup were included in this study. We analyzed 106 cases of dislocation in 74 patients. For all patients, we collected reason for revision, and classified index surgery as septic or aseptic. RESULTS: Overall, 106 dislocations occurred (106/924, 11.5%). Thirty-nine cases (52.7%) had a dislocation after a septic exchange THA, while in 35 patients (47.3%), a dislocation occurred after an aseptic rTHA. In 29 patients (39.2%), successful closed reduction under general anesthesia was feasible, while the majority of cases required open reduction. In 31 of these patients (67.4%), open reduction was combined with a revision arthroplasty. CONCLUSIONS: In case of DM cup dislocation, there is a low success rate of closed reduction. To prevent re-dislocation, total revision leads to a significantly reduced risk compared to open or closed reduction alone. Careful X-ray analysis for a halo sign showing intra-prosthetic DM cup dislocation is mandatory to avoid futile reduction attempts. LEVEL OF EVIDENCE: III.

What is the failure rate of constrained liners in complex revision total hip arthroplasty?

BACKGROUND: Recurrent hip dislocation after multiple revision total hip arthroplasty is a severe complication. Therefore, constrained acetabular liners (CL) have been used during salvage procedures. We report our experience of constrained liners in a re-revision setting with focus on re-dislocation. We also evaluated acetabular and femoral bone loss as potential risk factor. METHODS: Between January 2013 and December 2016, 65 patients were treated in a single institution for revision and re-revision hip arthroplasty using CL. The indication for using a CL was a high risk of re-redislocation after multiple recurrent hip dislocation including failed Dual Mobility Cups (DMC). Compromising soft tissue defects as well as severe bone defect were therefore regarded as high risks. Thirty-eight patients (77.6%) underwent a minimum of three surgical procedures before the index revision procedure. Sixteen patients (24.6%) were excluded as they were lost to follow-up, expired before minimum follow-up or refused study participation, leaving 49 patients in the analysis (75.4%). The mean follow-up was 62 months (44-74; SD = 7.7). We assessed the following potential risk factors for revision or dislocation: type of surgical setting (septic/aseptic), BMI, cup inclination angle, size of liner used and acetabular and femoral bone loss according to Paprosky classification. The primary endpoints were dislocation or repeat revision for any reason. RESULTS: Of the 49 patients, we found an overall re-revision rate of 40.8% (20/49) and a dislocation rate of 30.6% (15/49). There were no significant differences among the surgical re-revision rate or dislocation rate as a factor of patient characteristics. In terms of bone loss, there was a trend towards higher revision rates for increasing acetabular and femoral bone loss, but without statistical significance. CONCLUSIONS: We found the use of a constrained liner in a re-revision setting still bears a high risk of re-revision and re-dislocation. Therefore we restrained from using constrained liners in favour of Dual mobility cups. In this study there was no significant higher dislocation rate in the subgroup of periprosthetic infection. Furthermore the rigid design of a constrained liner bears the known risk of structural failure of acetabular reconstruction implants. Severe acetabular or femoral bone defects seem to have an impact on the revision rate, but not on the dislocation rate with regards to the restored offset and center of the hip. Results have to be taken into context such that the study population inherently has a predisposition for poorer outcomes. Indications should be strongly filtered for patients at high risk for recurrent hip joint dislocation including failed DMCs with only limited bone loss and moderate soft tissue defects. Our modification to the existing classification with a high inter and intraobserver reliability will make future studies more comparable regarding revisions and bone stock loss. Still further research using objective and reproducible parameters is needed to better analyze data especially in the background of complex revision hip arthroplasty.

Remote diagnostic imaging using artificial intelligence for diagnosing hip dysplasia in infants: Results from a mixed-methods feasibility pilot study.

Objectives: Infant hip dysplasia or Developmental Dysplasia of the Hip (DDH) occurs in 1-2% of births worldwide and leads to hip arthritis if untreated. We sought to evaluate the feasibility of implementing an artificial intelligence-enhanced portable ultrasound tool for infant hip dysplasia (DDH) screening in primary care, through determining its effectiveness in practice and evaluating patient and provider feedback. Methods: A US-FDA-cleared artificial intelligence (AI) screening device for DDH (MEDO-Hip) was added to routine well-child visits from age 6 to 10 weeks. A total of 306 infants were screened during a 1-year pilot study within three family medicine clinics in Alberta, Canada. Patient and provider satisfaction were quantified using the System Usability Survey (SUS), while provider perceptions were further investigated through semi-structured interviews. Results: Provider and user surveys commonly identified best features of the tool as immediate diagnosis, offering reassurance/knowledge and avoiding travel, and noted technical glitches most frequently as a barrier. A total of 369 scans of 306 infants were performed from Feb 1, 2021 until Mar 31, 2022. Eighty percent of hips scanned were normal on initial scans, 14% of scans required a follow-up study in the primary care clinic, and DDH cases were identified and treated at the expected 2% rate (6 infants). Conclusions: It is feasible to implement a point-of-care ultrasound AI screening tool in primary care to screen for infants with DDH. Beyond improved screening and detection, this innovation was well accepted by patients and fee-for-service providers with a culture and history of innovation.