Development Of Avascular Necrosis Research Articles

Clinical features of pediatric femoral neck fractures and analysis of risk factors for avascular necrosis of the femoral head: A retrospective case-control study of 45 patients.

ObjectivesTo summarize the clinical features of pediatric femoral neck fractures and analyze the risk factors for avascular necrosis of the femoral head. MethodsA retrospective analysis of the case data of pediatric femoral neck fractures treated in our hospital from January 2010 to December 2022, including gender, age, fracture type, causative factors, and surgical details. The occurrence of avascular necrosis of the femoral head was recorded and risk factors were analyzed. ResultsFrom January 2010 to December 2022, a total of 45 cases of femoral neck fractures were treated in our hospital with a median age at onset of 93 months (IQR=81) and a median time from injury to surgery of 96 hours (IQR=46). Closed reduction was performed in 36 cases, while open reduction was performed in 9 cases. Avascular necrosis of the femoral head occurred in 29 cases postoperatively, while it did not occur in 16 cases. Increased time from injury to surgery and greater degree of fracture displacement were independent risk factors for avascular necrosis of the femoral head. The risk of avascular necrosis in Garden IV type femoral neck fractures was significantly higher than in Garden II and III type patients. An injury-to-surgery time exceeding 82.5 hours was identified as a critical threshold for the development of avascular necrosis of the femoral head. ConclusionPediatric femoral neck fractures have a low incidence rate and are mostly caused by high-energy trauma, often resulting in severe injuries. Therefore, actively maintaining stable vital signs and properly managing associated injuries, timely surgical intervention for femoral neck fractures, achieving good reduction and fixation of displaced fractures are crucial in the treatment of pediatric femoral neck fractures.

Protective effect of modified lange "second position" for developing avascular necrosis following closed reduction for developmental dysplasia of the hip.

Developmental Dysplasia of the Hip (DDH) is a condition affecting hip joint development in children, presenting multiple manifestations. Immobilization methods to ensure hip concentricity, such as the human position and modified Lange position, vary in effectiveness and risks, especially avascular necrosis. The purpose of this study was to identify whether closed reduction (CR), with two different immobilization techniques, is effective in avoiding complications such as residual hip dysplasia (RHD), re-dislocation, and Avascular Necrosis (AVN). A total of 66 patients with DDH (84 hips) were treated with two different techniques of immobilization (groups A and B); the mean age at the time of reduction was 8 (6-13) months. The rates of RHD, Re-dislocation, and AVN were determined with a minimum follow-up of 48 months in both techniques. The Chi-square analysis conducted across the study groups unveiled that patients in Group B demonstrated a protective effect against AVN compared to those in Group A (OR: 0.248, 95% CI: 0.072-0.847, p = 0.026). However, no statistically significant differences were found between the groups concerning RHD (p = 0.563) and re-dislocation (p = 0.909). After the initial Human Position immobilization, the second cast with the modified Lange "second position" demonstrated a protective effect compared with maintaining the Human Position immobilization throughout the immobilization period, reducing the likelihood of AVN development in patients undergoing closed reduction for developmental dysplasia of the hip.

Is choice of approach associated with risk of avascular necrosis in pediatric septic hip?

Septic arthritis of the hip in children and adolescents is a common condition requiring timely diagnosis and intervention. Surgical irrigation and debridement is typically performed through the anterior approach because of concerns about injury to the medial femoral circumflex artery leading to avascular necrosis. While there are multiple studies investigating the sequelae of anterior and medial approaches for reduction of developmental dislocation of the hip, none have compared these approaches for the pediatric septic hip. We hypothesize that there will be no significant difference in the rate of avascular necrosis when comparing the medial and anterior approaches to the septic hip in pediatric patients. A retrospective review was performed of pediatric septic hips treated with irrigation and debridement through either a medial or anterior approach at a single institution over an 18-year period of time. The primary outcome measure was the development of avascular necrosis. Thirteen of 164 patients (7.9%) developed avascular necrosis. Avascular necrosis was noted in 9 of 101 patients who had anterior approach and 4 of 63 patients who underwent medial approach (p = 0.76). The average age for patients developing avascular necrosis was 10.0 years old versus 6.8 years old in patients who did not develop avascular necrosis (p = 0.01). The average follow-up was 3.3 years in patients with avascular necrosis versus 1.5 years for patients who did not develop avascular necrosis (p = 0.01). Medial approach to the pediatric septic hip does not increase the rate of avascular necrosis compared to the anterior approach. Retrospective comparison study, Level III.

Risk factors for avascular necrosis of the femoral head after developmental hip dislocation reduction surgery and construction of Nomogram prediction model

BackgroundTo analyze the risk factors for the development of avascular necrosis (AVN) of the femoral head after reduction surgery in children with developmental hip dysplasia (DDH), and to establish a prediction nomogram.MethodsThe clinical data of 134 children with DDH (169 hips) treated with closure reduction or open reduction from December 2016 to December 2019 were retrospectively analyzed. Independent risk factors for AVN after DDH reduction being combined with cast external immobilization were determined by univariate analysis and multivariate logistic regression and used to generate nomograms predicting the occurrence of AVN.ResultsA total of 169 hip joints in 134 children met the inclusion criteria, with a mean age at surgery of 10.7 ± 4.56 months (range: 4–22 months) and a mean follow-up duration of 38.32 ± 27.00 months (range: 12–94 months). AVN developed in 42 hip joints (24.9%); univariate analysis showed that the International Hip Dysplasia Institute (IHDI) grade, preoperative development of the femoral head ossification nucleus, cartilage acetabular index, femoral head to acetabular Y-shaped cartilage distance, residual acetabular dysplasia, acetabular abduction angle exceeding 60°, and the final follow-up acetabular index (AI) were associated with the development of AVN (P < 0.05). Multivariate logistic regression analysis showed that the preoperative IHDI grade, development of the femoral head ossification nucleus, acetabular abduction angle exceeding 60°, and the final follow-up AI were independent risk factors for AVN development (P < 0.05). Internal validation of the Nomogram prediction model showed a consistency index of 0.833.ConclusionPreoperative IHDI grade, preoperative development of the femoral head ossification nucleus, final AI, and acetabular abduction angle exceeding 60° are risk factors for AVN development. This study successfully constructed a Nomogram prediction model for AVN after casting surgery for DDH that can predict the occurrence of AVN after casting surgery for DDH.

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

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. 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? 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. 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). 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 IV, therapeutic study.

Talar Neck Fractures With Associated Ipsilateral Foot and Ankle Fractures Have a Higher Risk of Avascular Necrosis.

To determine if talar neck fractures with concomitant ipsilateral foot and/or ankle fractures (TNIFAFs) are associated with higher rates of avascular necrosis (AVN) compared with isolated talar neck fractures (ITNs). Retrospective cohort. Single level I trauma center. Skeletally mature patients who sustained talar neck fractures from January 2008 to January 2017 with at least 6-month follow-up. Based on radiographs at the time of injury, fractures were classified as ITN or TNIFAF and by Hawkins classification. The primary outcome was the development of AVN based on follow-up radiographs, with secondary outcomes including nonunion and collapse. There were 115 patients who sustained talar neck fractures, with 63 (55%) in the ITN group and 52 (45%) in the TNIFAF group. In total, 63 patients (54.7%) were female with the mean age of 39 years (range, 17-85), and 111 fractures (96.5%) occurred secondary to high-energy mechanisms of injury. There were no significant differences in demographic or clinical characteristics between groups ( P > 0.05). Twenty-four patients (46%) developed AVN in the TNIFAF group compared with 19 patients (30%) in the ITN group ( P = 0.078). After adjusting for Hawkins classification and other variables, the odds of developing AVN was higher in the TNIFAF group compared with the ITN group [odds ratio, 2.43 (95% confidence interval, 1.01-5.84); ( P = 0.047)]. This study found a significantly higher likelihood of AVN in patients with talar neck fractures with concomitant ipsilateral foot and/or ankle fractures compared to those with isolated talar neck fractures after adjusting for Hawkins classification and other potential prognostic confounders. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Intraoperative Epiphyseal Perfusion Monitoring Does Not Reliably Predict Osteonecrosis Following Treatment of Unstable SCFE.

Avascular necrosis (AVN) remains the most dreaded complication of unstable slipped capital femoral epiphysis (SCFE) treatment. Newer closed reduction techniques (with perfusion monitoring) have emerged as a technically straightforward means to address residual SCFE deformity while still minimizing the risk of osteonecrosis. However, limited data exists regarding the reliability of intraoperative epiphyseal perfusion monitoring to predict the development of AVN. The purpose of this study was to evaluate its reliability. We retrospectively reviewed all patients with unstable SCFE who underwent closed or open reduction with epiphyseal perfusion monitoring using an intracranial pressure (ICP) probe from 2015 to 2023 at a single institution with a minimum 6-month radiographic follow-up. Demographic, clinical, and radiographic data were recorded, including duration of symptoms, type of reduction, capsulotomy performed, presence of a waveform on ICP monitoring after epiphyseal fixation, and development of AVN on follow-up radiographs. Our cohort included 33 hips (32 patients), of which 60.6% (n=20) were male. The average age was 12.5±1.8 years, with a median follow-up of 15.8 months. Eleven hips were treated with open reduction using the modified Dunn technique (10 hips) or anterior approach (1 hip), and 22 hips were treated with inadvertent (5 hips) or purposeful closed reduction using the Leadbetter technique (17 hips). Overall, 8 of the 33 hips in our series (24.2%) developed AVN, 6 of which (20%) had a pulsatile waveform on intraoperative epiphyseal perfusion monitoring. The overall rate of AVN after closed reductions was 31.8% (7 of 22 hips); the incidence of AVN after closed reduction with a detectable waveform was 30% (6 of 20 hips). There was no significant association between time to surgery ( P =0.416) or type of reduction ( P =0.218) and the incidence of AVN. In this series, intraoperative epiphyseal perfusion monitoring did not reliably predict the development of osteonecrosis. To our knowledge, this is the first study to report AVN after demonstrable intraoperative epiphyseal perfusion following closed reduction of unstable slips. Level IV: case series-therapeutic study.

A Comprehensive Review of COVID-19-Infection- and Steroid-Treatment-Associated Bone Avascular Necrosis: A Multi-Study Analysis

Background: The COVID-19 pandemic has presented numerous challenges to the global healthcare system and emerging evidence suggests a potential link between COVID-19 treatment, specifically steroid therapy, and the development of avascular necrosis (AVN) of the hip. This review aims to provide a comprehensive overview of recent studies and case reports investigating the relationship between COVID-19, corticosteroid therapy, and the development of AVN. Understanding the nuances of AVN in the context of COVID-19 is crucial for healthcare professionals to navigate treatment decisions and mitigate potential complications. Materials and Methods: The Preferred Reporting Items for Systematic Reviews and a Meta-Analysis (PRISMA) were used in the systematic review until 1 September 2023. The full texts of the remaining twenty-three (n = 23) articles were independently reviewed by the authors of this review. Conclusions: The association between steroid therapy for COVID-19 and the development of hip AVN is a noteworthy concern even though no relationship is evident between the duration of treatment, cumulative dosage of medication, maximum daily dosage received, and presence of AVN. Further research with larger cohorts and long-term follow up is needed to better understand the causative relationship and optimal management strategies for hip AVN in the context of COVID-19 and steroid therapy.

Identifying risk factors for osteonecrosis after talar fracture.

To identify patient, injury, and treatment factors associated with development of avascular necrosis (AVN)following talar fractures, with particular interest in modifiable factors. Retrospective chart review. 21 US trauma centers and 1 UK trauma center. 2,220 patients with talar neck and/or body fractures. Open reduction internal fixation of talar neck and body fractures. Development of AVN. Infection, nonunion, and arthritis were secondary outcomes. 796 patients (408 M; 388 F; age 18-81, avg 38.6) with 796 (532R; 264L) fractures were included and were classified as Hawkins 1(51), IIA(71), IIB(113), III(158), IV(40), neck plus body (177), body (188). 336/798 developed AVN (42%), more commonly following any neck fracture (47.0%) vs isolated body fracture (26.1%, p<0.001). More severe Hawkins' classification, combined neck and body fractures, body mass index (BMI), tobacco smoking, right-sided fractures, open fracture, dual anteromedial and anterolateral surgical approaches, and associated medial malleolus fracture were associated with AVN. After multivariate regression, fracture type, tobacco smoking, open fractures, dual approaches, age, and BMI remained significant.Excluding late cases (>7 days), time to joint reduction for Hawkins type IIB-IV neck injuries was no different for those who developed AVN or not. AVN rates for reduction of dislocations within 6 hours of injury vs >6 hours were 48.8% and 57.5%, respectively. Complications included 60 (7.5%) infections and 70 (8.8%) nonunions. 42% of all patients developed AVN, with talar neck fractures, more displaced fractures and open injuries having higher rates. Injury-related factors are most prognostic of AVN risk. Surgical technique to emphasize anatomical reduction, without iatrogenic damage to remaining blood supply is essential. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Treatment Outcomes After Open Reduction, Varus Derotational Osteotomy and Dega Acetabuloplasty in Children With Dislocated Dysplastic Hip: Retrospective Analysis

Background. Treatment of developmental dysplasia of the hip (DDH) poses a great challenge for pediatric orthopedists due to the high risk of complications, the most severe of which are avascular necrosis of the femoral head and recurrent dislocation. In the most severe form of dysplasia, hip dislocation, the surgery is indicated after 18 months of age. However, the issue of determining the exact surgical intervention remains controversial.&#x0D; The aim of the study was to provide our own midterm treatment outcomes of patients with DDH, who underwent open reduction for DDH through a modified Ganz digastric approach and varus derotational femur osteotomy combined with Dega acetabuloplasty.&#x0D; Methods. The treatment outcomes of 12 patients with DDH grade III-IV according to the IHDI classification at the age of 1.5 to 3.5 years were analyzed. Thirteen operations were performed: open reduction, derotational varus femur osteotomy combined with Dega acetabuloplasty. In one case, surgery was performed bilaterally in two stages. The average follow-up period was 31.9±4.9 months (from 12 to 66 months). To evaluate the correction performed, a comparative analysis of X-ray images (acetabular index (AI) and femoral neck-shaft angle (FNSA) and Reimers migration index (MI)) was performed before, after surgery and at the last follow-up. The incidence of complications was assessed: recurrent dislocation, avascular necrosis of the femoral head (AVN), nonunion, infection, and loss of correction. In 8 patients with a follow-up period of more than 2 years, the limb length discrapancy was assessed.&#x0D; Results. Dega acetabuloplasty allowed to reduce the AI value from 38.62° to 18.76° (p0.05) after surgery and to 20.61° at the last follow-up. As a result of varus derotational femur osteotomy, a decrease in the FNSA value was noted from 143.62° to 110.53° (p0.05). AVN was observed in 4 cases in 3 patients (25%) (including the patient who underwent bilateral surgery). At the last follow-up, the FNSA increased to 119.11° in 9 patients without AVN and decreased to 87.75° in patients with AVN. In one patient with AVN, the development of medial dislocation of the femoral head due to progressive varus deformity was noted (up to 41°). No nonunions or infectious complications were observed.&#x0D; Conclusion. The combination of open reduction, varus derotational femur osteotomy with Dega acetabuloplasty is an effective method for treatment of DDH in toddlers. The small sample size and the absence of a control group do not allow us to draw conclusions regarding the effectiveness of the modified Ganz digastric approach as a measure to prevent the development of avascular necrosis of the femoral head after surgery.

Is COVID-19 an independent risk factor for the development of avascular necrosis of the hip? A retrospective study to evaluate the factors associated with avascular necrosis of the hip in patients who had COVID-19 infection.

The cumulative effect of hyper-coagulative COVID-19 disease and using steroids leads to increased avascular necrosis (AVN) hip incidence. This study aims to correlate the various factors of COVID-19 infection with the occurrence of AVN hip. It is a retrospective cross-sectional study of non-traumatic AVN hip patients with a history of COVID-19 infection. A total number of 50 patients satisfied the inclusion criteria. The following details were obtained: (a) patient's demographics, (b) COVID-19: interval of infection and groin pain, duration of symptoms, severity, steroid intake, (c) AVN hip: involved side, Ficat-Arlet staging. The mean age was 36.3 years (range: 20-60), and body mass index (BMI) was 25.13 kg/m2 (range: 18.50-31.50). There were 45 males and five females. Sixty percent (30) of patients managed at home, 24% (12) required admission into the ward, 2% (1) were in ICU only, and 14% (7) admitted to both ICU and ward. The mean interval of COVID-19 infection and onset of hip pain was 359.02 days (range: 10-822 days). Thirty-eight percent (19) patients required steroids (injection and oral), 46% (23) took steroids (oral only), whereas 16% (8) recovered without steroids. The stage of AVN correlated with the severity of COVID-19 infection (p-value -0.038) and significant improvement in VAS and HHS after treatment in each stage. The mean follow-up was 9.79 months (6-19 months). A low-dose steroid intake with moderate to severe COVID-19 infection produces an additive effect on the development of AVN hip. Most affected individuals were adult males, and stage II AVN was the most common, managed with bisphosphonates and core decompression for short intervals.

High rate of avascular necrosis but excellent patient-reported outcomes after open reduction and internal fixation (ORIF) of proximal humerus fracture dislocations: should ORIF be considered as primary treatment?

Proximal humerus fracture dislocations, excluding 2-part greater tuberosity fracture dislocations, are rare injuries. Outcomes after open reduction and internal fixation (ORIF) of these injuries have not been well described in the literature. The purpose of this study was to report the radiographic and functional outcomes of patients who underwent ORIF of a proximal humerus fracture dislocation. All skeletally mature patients who underwent ORIF of a proximal humerus fracture dislocation between 2011 and 2020 were identified. Patients with isolated greater tuberosity fracture dislocations were excluded. The primary outcome was American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score at a minimum of 2 years. Secondary outcomes were the development of avascular necrosis (AVN) and reoperation rate. Twenty-six patients met the inclusion criteria. The mean age was 45 years (standard deviation 16), and 77% were men. Median time to reduction and surgery was 1 day (interquartile range [IQR] 1-5). There were 2 (8%) Neer 2-part fractures, 7 (27%) 3-part, and 17 (65%) 4-part fractures. Fifty-four percent (54%) involved the anatomic neck and 31% included a head-split component. Thirty-nine percent (39%) were anterior dislocations. The rate of AVN was 19%. The reoperation rate was 15%. Reoperations included removal of hardware (2), subscapularis repair (1), and manipulation under anesthesia (1). No patients went on to arthroplasty. ASES scores were available for 22 patients (84%) including 4 of 5 patients with AVN. The median ASES score at a mean of 6.0 years postoperatively was 98.3 (IQR 86.7-100, range 63.3-100) and was not different in those with or without AVN (median 98.3 vs. 92.0, P=.175). Only the presence of medial comminution and nonanatomic head shaft alignment on postoperative radiographs were associated with increased risk of AVN. Radiographic rates of AVN (19%) and reoperation (15%) were high in this series of patients undergoing ORIF of proximal humerus fracture dislocations. Despite this, none of the patients required arthroplasty, and patient-reported outcome scores at an average of 6 years postinjury were excellent, with a median ASES score of 98.5. ORIF should be considered as primary method of treatment in proximal humerus fracture dislocations not only in young patients but also middle-aged patients.

Severity of hip dysplasia as the major factor affecting outcome of closed reduction in children with hip dysplasia.

The objective of this study was to analyze a multicenter cohort of children with developmental dysplasia of the hip (DDH) who underwent treatment with closed reduction. We sought to report the effects that severity of hip dysplasia and age have on the development of femoral head avascular necrosis (AVN) and the need for additional procedures. All patients with DDH and minimum 2 years of follow-up who underwent closed reduction were identified. The following variables were recorded: sex, laterality of hip involvement, age, acetabular index (AI), and International Hip Dysplasia Institute (IHDI) grade. The effects of patient age and pre-procedure IHDI grade on the rate of AVN and need for additional procedures after the closed reduction were analyzed using an alpha of 0.05. Seventy-eight total hips were included in the final analysis. The average patient age was 12 months. AVN of the femoral head was reported in 24 hips (30.8%) and 32 hips (41.0%) required additional surgery. Higher pre-op IHDI grade was associated with higher risk of developing Bucholz-Ogden grades II-IV AVN of the femoral head ( P = 0.025) and requiring additional surgery ( P = 0.033) regardless of patient age. There were no statistically significant differences for the effect of age on the measured outcomes ( P > 0.05). These findings suggest that severity of dislocation (IHDI grade) is a significant risk factor for the development of AVN and need for additional procedure.

Modified Dunn Technique for Unstable Slipped Capital Femoral Epiphysis: A Midterm Single Center Experience.

Objective To evaluate the safety and reproducibility of the surgery for unstable slipped capital femoral epiphysis (SCFE) through the modified Dunn technique in a single center cohort from Brazil. Methods We retrospectively analyzed a cohort of patients submitted to this procedure by a single surgeon who was a hip preservation specialist. Demographic data and radiographic angles were evaluated for the relative risk (RR) of avascular necrosis (AVN) using a log-binomial regression model with simple and random effects. Results Among the 30 patients (30 hips) with a mean age of 11.79 years at the time of the operation, there were 17 boys and 18 left hips, which were operated on in a mean of 11.5 days after the slip. The mean follow-up was of 38 months. The preoperative Southwick angle averaged 60.69° against 4.52° postoperatively ( p < 0.001). A larger preoperative slip angle was associated with the development of AVN (RR: 1.05; 95% confidence interval [95%CI]: 1.02-1.07; p < 0.01). The overall AVN rate was of 26.7%. Function was good or excellent in 86% of uncomplicated hips, and poor in 87.5% of the partients who developed AVN, as graded by the Harris Hip Score. There was no statistical relationship between epiphyseal bleeding and AVN development ( p = 0.82). Conclusion The modified Dunn technique is associated with restoration of the femoral alignment and function after unstable SCFE, when uncomplicated. Moreover, it was shown to be reproducible in our population, with a rate of 26% of femoral head necrosis.

Avascular necrosis in systemic lupus erythematosus patients: Analysis of the demographics, clinical manifestations, management and outcomes

Avascular necrosis (AVN) is a rare complication of systemic lupus erythematosus (SLE) that may develop from the disease or its treatment. To present the clinical characteristics, management and outcomes of SLE patients with AVN. The SLE patients with AVN on X-ray or magnetic resonance imaging (MRI) following up at Fatima Memorial Hospital College of Medicine and Dentistry Shadman, Lahore, Pakistan were studied. Detailed medical history, clinical examination, laboratory investigations, treatment details and outcomes were recorded. Out of 230 SLE patients, 20 (8.6%) had AVN; 80% females, F:M 4:1 with a mean age at onset of SLE 19.8 ± 6.5 years, and mean duration till occurrence of AVN 3.9 ± 2.3 years. AVN developed within 4 years of onset in 80% of patients. Mucocutaneous symptoms were the most common presentation (95%) and 65% had positive antiphospholipid antibodies. Until AVN development, all patients received a mean of 3.5 ± 0.7 g pulse steroid and a mean cumulative oral steroid dose of 18.6 ± 6.2 g. AVN was in the hip joint in 95% of cases, 80% were bilateral. AVN was grade II in 45% patients, grade III in 25% (n = 5), I in 20% (n = 4) and grade IV in 10% (n = 2). Grade I and II had preserved joint function and didn't need any surgery compared to stage III and IV. In SLE patients, AVN is a relatively early complication occurring within 4 years of illness in patients with a young age at onset, and have a better outcome when detected at earlier stages.

Avascular Necrosis in Renal Transplant Patients

Kidney transplant recipients are at increased risk for avascular necrosis due to steroid use and accompanying comorbidities. Concerning risk factors, uncertainty still exists. We evaluated the clinical characteristics and risk factors of avascular necrosis in kidney transplant recipients. Symptomatic avascular necrosis was found by magnetic resonance imaging in 33 of 360 kidney transplant patients between 2005 and 2021. The patients' clinical characteristics, biochemical testing, and medications were evaluated. We found the frequency of avascular necrosis to be 9.7% during the follow-up period. If the total steroid dosage used was more than 4 g in the first 3 months, the risk of developing avascular necrosis increased 4.08 times, and the presence of cytomegalovirus disease increased the risk by 4.03 times. Avascular necrosis was observed bilaterally in 60.6% of cases and at the femoral head in 66.7%. The frequency of avascular necrosis was highest in the first and second years posttransplant. We found that avascular necrosis appears most frequently in the first 2 years after kidney transplant and the most important risk factors are cumulative steroid dose and cytomegalovirus disease. In the follow-up of kidney transplant patients, it is important to use low-dose steroid doses if possible. Of note, preventing the development of cytomegalovirus disease by screening and prophylaxis for cytomegalovirus is also important in reducing the development of avascular necrosis.

The incidence, risk factors, and outcomes of symptomatic avascular necrosis of bone among Chinese pediatric patients with acute lymphoblastic leukemia

Avascular necrosis (AVN) of bone is a debilitating complication of pediatric patients with acute lymphoblastic leukemia (ALL). While it is extensively studied and reported in Western population, studies focused on Orientals are limited. This study aims to evaluate the incidence, risk factors, and clinical outcomes of AVN among Chinese children with ALL. This study is a retrospective, territory-wide population-based cohort study of pediatric patients with ALL enrolled on one of the three consecutive ALL study protocols (ALL-IC-BFM 2002, CCLG-ALL 2008, and CCCG-ALL 2015). A total of 24 out of 533 pediatric subjects with ALL (4.5%) had symptomatic AVN. Age was the single most important risk factor associated with the development of AVN. Only three patients were below age of 10 at the time of diagnosis of ALL. The incidences of AVN in patients aged above and below 10 years were 18.2% ± 3.6% and 0.8% ± 0.5%, respectively, and were significantly different (p < 0.005). Treatment protocol, immunophenotype, and gender were not predictive of AVN. Among the 24 patients, five required orthopedic interventions in view of progressive and severe disease. For subjects with hip joints involvement, follow-up assessments showed 12 of 22 hip joints had radiological progression over a median duration of 3.63 years. Seventeen of them did not have pain at the latest follow-up and among patients with pain (n=7), five did not experience any limitation on activities of daily living while two required use of walking aids or wheelchair. The incidence of symptomatic AVN in Chinese ALL patients was comparable to other studies in Western population. Adolescent age more than 10 years old was recognized to be the most important factor for development of AVN. Significant proportion of patients had radiological progression over time with a small percentage of subjects had daily activities affected.

Association of Talar Neck Fractures With Body Extension and Risk of Avascular Necrosis.

The objective of this study was to determine whether talar neck fractures with proximal extension (TNPE) into the talar body are associated with higher rates of avascular necrosis (AVN) compared to isolated talar neck (TN) fractures. A retrospective review of patients sustaining talar neck fractures at a level I trauma center from 2008 to 2016 was performed. Demographic and clinical data were collected from the electronic medical record. Fractures were characterized as TN or TNPE based on initial radiographs. TNPE was defined as a fracture that originates on the talar neck and extends proximal to a line subtended from the junction of the neck and the articular cartilage dorsal to the anterior portion of the lateral process of the talus. Fractures were classified according to the modified Hawkins classification for analysis. The primary outcome was the development of AVN. Secondary outcomes included nonunion and collapse. These were measured on postoperative radiographs. There were 137 fractures in 130 patients, with 80 (58%) fractures in the TN group and 57 (42%) in the TNPE group. Median follow-up was 10 months (interquartile range, 6-18 months). The TNPE group was more likely to develop AVN as compared to the TN group (49% vs 19%, P < .001). Similarly, the TNPE group had a higher rate of collapse (14% vs 4%, P = .03) and nonunion (26% vs 9%, P = .01). Even after adjusting for open fracture, Hawkins fracture type, smoking, and diabetes, AVN still remained significant for the TNPE group as compared to the TN group with an odds ratio of 3.47 (95% CI, 1.51-7.99). We found a higher rate of AVN, subsequent collapse, and nonunion in patients with TNPE compared to isolated TN fractures. Level III, retrospective cohort study.

Hospital transfer and delayed reduction of traumatic hip dislocations.

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. 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 6months 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. 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 (13.8h vs 5.7h); however, transfer status was not found to be an independent risk factor for the measured outcomes. 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 8h in time to reduction compared to those who presented directly to a trauma center. Of the 27 patients with a reduction delay greater than 12h, 26 (96%) were transferred.

The incidence of avascular necrosis in children with cerebral palsy after hip containment surgery.

To establish the rate of avascular necrosis after hip reconstruction surgery in children with cerebral palsy and to identify risk factors that influence the development of avascular necrosis in this population. An institutional review board-approved retrospective review was conducted on children with cerebral palsy who underwent hip containment surgery at a single institution. Radiographs were evaluated at three time points. The Reimer's migration percentage, neck shaft angle, epiphyseal shaft angle, acetabular index, center edge angle, and acetabular angle were measured. The presence of avascular necrosis was evaluated and graded by the Bucholz/Ogden and the Kalamchi/MacEwen classification systems. Multivariate logistic regression was performed to identify risk factors associated with the development of avascular necrosis. A total of 154 children with cerebral palsy underwent hip containment surgery on 223 hips. Twenty-nine children (18.8%) underwent both pelvic and femoral procedures; 36 children (23.4%) had only femoral procedures; 47 children (30.5%) had femoral and soft tissue; and 42 children (27.3%) had pelvic, femoral, and soft tissue procedures. Using the Bucholz and Ogden or the Kalamchi classifications, the rate of avascular necrosis was 24.7% (38/154). Of the variables evaluated, preoperative Reimers was found to be significant predictors of avascular necrosis. The rate of avascular necrosis was 26.7% for Gross Motor Functional Classification System level III, 24.1% for Gross Motor Functional Classification System level IV, and 27.3% for Gross Motor Functional Classification System level V. The overall rate of avascular necrosis in children undergoing hip containment surgery was 26.7%. Together, age at surgery, open reduction, previous surgery, preoperative Reimers, and estimated blood loss contributed to the development of postoperative avascular necrosis; however, only preoperative Reimers significantly contributed to the development of avascular necrosis in children with cerebral palsy undergoing hip containment procedures.