Idiopathic Osteonecrosis Research Articles (Page 2)

BackgroundPrevious studies reported good outcomes of acetabular cup placement using portable navigation systems during THA. However, we are aware of no prospective studies comparing inexpensive portable navigation systems using augmented reality (AR) technology with accelerometer-based portable navigation systems in THA.Questions/purposes(1) Is the placement accuracy of the acetabular cup using the AR-based portable navigation system superior to that of an accelerometer-based portable navigation system? (2) Do the frequencies of surgical complications differ between the two groups?MethodsWe conducted a prospective, two-arm, parallel-group, randomized controlled trial involving patients scheduled for unilateral THA. Between August and December 2021, we treated 148 patients who had a diagnosis of osteoarthritis, idiopathic osteonecrosis, rheumatoid arthritis, or femoral neck fracture and were scheduled to undergo unilateral primary THA. Of these patients, 100% (148) were eligible, 90% (133) were approached for inclusion in the study, and 85% (126) were finally randomized into either the AR group (62 patients) or the accelerometer group (64 patients). An intention-to-treat analysis was performed, and there was no crossover between groups and no dropouts; all patients in both groups were included in the analysis. There were no differences in any key covariates, including age, sex, and BMI, between the two groups. All THAs were performed via the modified Watson-Jones approach with the patient in the lateral decubitus position. The primary outcome was the absolute difference between the cup placement angle displayed on the screen of the navigation system and that measured on postoperative radiographs. The secondary outcome was intraoperative or postoperative complications recorded during the study period for the two portable navigation systems.ResultsThere were no differences between the AR and accelerometer groups in terms of the mean absolute difference in radiographic inclination angle (3° ± 2° versus 3° ± 2° [95% CI -1.2° to 0.3°]; p = 0.22). The mean absolute difference in radiographic anteversion angle displayed on the navigation screen during surgery compared with that measured on postoperative radiographs was smaller in the AR group than that in the accelerometer group (2° ± 2° versus 5° ± 4° [95% CI -4.2° to -2.0°]; p < 0.001). There were few complications in either group. In the AR group, there was one patient each with a surgical site infection, intraoperative fracture, distal deep vein thrombosis, and intraoperative pin loosening; in the accelerometer group, there was one patient each with an intraoperative fracture and intraoperative loosening of pins.ConclusionAlthough the AR-based portable navigation system demonstrated slight improvements in radiographic anteversion of cup placement compared with the accelerometer-based portable navigation system in THA, whether those small differences will prove clinically important is unknown. Until or unless future studies demonstrate clinical advantages that patients can perceive that are associated with such small radiographic differences, because of the costs and the unquantified risks associated with novel devices, we recommend against the widespread use of these systems in clinical practice.Level of EvidenceLevel I, therapeutic study.

Legg-Calvé-Perthes disease is juvenile idiopathic osteonecrosis of the femoral head (ONFH) that has no effective clinical resolutions. Previously, local injection of bone morphogenetic protein-2 (BMP2) for ONFH treatment showed a heterogeneous bone repair and a high incidence of heterotopic ossification (HO) due to the BMP2 leakage. Here, we developed a BMP2-hydrogel treatment via a transphyseal bone wash and subsequential injection of BMP2-loaded hydrogel. In vivo studies showed that a hydrogel of gelatin-heparin-tyramine retained the BMP2 for four weeks. The injection of the hydrogel can efficiently prevent leakage. With the bone wash, the injected hydrogel had a broad distribution in the head. In vivo studies on pigs revealed that the BMP2-hydrogel treatment produced a homogeneous bone regeneration without HO. It preserved the subchondral contour and restored the subchondral endochondral ossification, although it increased growth plate fusions. In summary, the study demonstrated a promising BMP2-hydrogel treatment for ONFH treatment, especially for teenagers.

To characterize pathoetiologic associations of heritable thrombophilia-hypofibrinolysis with idiopathic (primary) multifocal osteonecrosis (ON) (≥3 ON anatomic sites), we prospectively studied 28 women and 12 men with primary multifocal ON compared with 27 women and 24 men with primary nonmultifocal ON (<3 sites) and 110 healthy controls without ON. The 40 cases with primary multifocal ON differed from controls for 3 familial thrombophilias: Factor V Leiden heterozygosity (6 of 40 [15%] vs 2 of 109 [2%], P=.002), G20210A prothrombin gene heterozygosity (6 of 40 [15%] vs 3 of 110 [3%], P=.011), and high (>150%) Factor VIII (8 of 40 [20%] vs 7 of 103 [7%], P=.031). These case-control familial coagulation differences paralleled those in 51 concurrently evaluated cases with primary nonmulti-focal ON, 7 of 51 (14%) of whom had Factor V Leiden heterozygosity vs 2% of controls (P=.005) and 14 of 44 (32%) of whom had high Factor VIII vs 7 of 103 (7%) of controls (P=.0002). Recognition of familial thrombophilia as a common pathoetiology of primary multifocal ON provides an opportunity for early anticoagulation (before joint collapse), allowing both prophylaxis and therapy aimed at relieving pain and slowing or stopping progression of the disease to joint collapse. [Orthopedics. 2023;46(3):164-168.].

Background:Treatment of osteonecrosis of the talus is challenging. Nonoperative management includes nonweightbearing treatment. Various types of hindfoot fusion procedures have been performed, but delayed union and shortening of the operated leg have reportedly occurred. In contrast, talar body prosthesis is a surgical procedure with potential that relieves pain, restores ankle joint function, and is not associated with leg-length discrepancy. The aim of this study was to investigate postoperative pain, clinical outcomes, activities of daily living (ADL), and quality of life (QOL) after total talar replacement in patients with osteonecrosis of the talus.Methods:Ten ankles in 10 patients with idiopathic osteonecrosis of the talus who were treated with a total talar replacement between 2007 and 2015 were included in the investigation. Scores according to the visual analog scale (VAS), Japanese Society for Surgery of the Foot (JSSF) ankle-hindfoot scale, Functional Independence Measure (FIM), and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) were assessed.Results:The VAS score significantly improved from a mean of 80 ± 8 points before surgery to 18 ± 22 points after surgery (P < .01). The JSSF ankle-hindfoot scale score significantly improved from a mean of 53 ± 12 points before surgery to 89 ± 7 points after surgery (P < .01). The FIM score significantly improved from a mean of 122 ± 1 points before surgery to 125 ± 1 points after surgery (P < .01). The mean postoperative SAFE-Q scores were as follows: 81 ± 10.3 points for pain, 78 ± 14.7 points for physical function, 90 ± 12.4 points for social function, and 83 ± 15.4 points for shoe-related.Conclusion:Total talar replacement is a useful treatment for patients with osteonecrosis of the talus. This replacement surgery preserves the function of the ankle and subtalar joints, and improves pain, ADL, and QOL.Level of Evidence:Level IV, case series.

Etiología de la osteonecrosis avascular de cadera y hombro. Cribado de la enfermedad de Gaucher

Introduction: Legg calves Perthes disease (LCPD) is caused mainly due to idiopathic osteonecrosis or AVN of the proximal femoral epiphysis leading to remodelling during period of development, this will gradually progress into onset of hip osteoarthritis depending upon the rate at which the sphericity and congruency of the femoral head deteriorate. LCPD is usually associated with a hinge abduction deformity, in this condition the major aspherical portion of the head is shifted laterally, in such deformity; Valgus intertrochanteric osteotomy has to been utilized for correction. Cheilectomy deals with excision of exuberant portion of femoral head epiphysis, thereby eliminating hinged abduction and facilitating containment, which also maintains the blood supply, buy protecting the surrounding soft tissue structures.Materials and Methods: We have included 10 patients for this study, from age group 9-16yrs, between July 15th to April 18. The criteria for patient selection being primarily adolescent age with radiological evidence of LCPD, with coxa plana and decreased range of motion. Patient under 10 years of age and with history of previous surgeries have been excluded. All the patients were planned preoperatively and operated under spinal anaesthesia. Through posterior kocherlangenback approach, capsulotomy was doneposterior-superiorly and lateral protuberance was identified and excised. A common feature through most surgeries being femoro-acetabular impingement (CAM type) secondary to aspherical femoral head. There were a total of 7 cases of complex CAM type deformities and 3 pincer induced deformities. Postoperatively weight bearing and ROM was restricted for 4 weeks. Physiotherapy protocol was followed for improving ROM. Patients were followed at 4,8,12 weeks to evaluate clinical and radiological progress.Results: Majority of the patient experienced improved pain after surgical intervention and 1 patient had worsening of pain at 3 months of followup. 2 patients had complication of delayed wound healing due to superficial infections. No further complications such as osteonecrosis and non-union were not observed.Conclusion: Though this study we can conclude that osteochondroplasty of the femoral head and neck performed in conjunction with other procedures, through the surgical dislocation of hip approach has improved pain and restored function in a majority of the patients, while avoiding any dreaded complications. Although the results were satisfactory in a 3 month follow up, we may conclude that a long term follow up is needed for the efficacy of this method in restoration of painless joint function and avoidance of arthroplasty at a later date.

Etiology of avascular necrosis of the hip and shoulder. Screening for Gaucher disease

Classification and Radiographic Characterization of Kienböck Disease.

Avascular necrosis (AVN) of the first metatarsal (MTT) head is an uncommon condition and it occurs most often as a complication after capital osteotomy in correction of hallux valgus deformity. Idiopathic osteonecrosis of the first MTT head in adolescent are rare and treatment is challenging (1,2). Many conditions have been proposed as predisposing factors of AVN, including trauma, hemoglobinopathies such as sickle-cell disease, steroid therapy, Cushing's disease, alcoholism, Gaucher's disease, Caisson's disease, and irradiation (3,4). However, etiology remains elusive. We described a case of an idiopathic AVN of the 1st MTT in adolescent treated by dorsal closing-wedge osteotomy, which to the authors' knowledge has not been described before.

Avascular necrosis (AVN) also referred to as osteonecrosis (ON) refers to inadequate perfusion to bone tissue resulting in death or necrosis of the bone. Although many known risk factors and etiologies exist, 20%-40% of AVN cases are idiopathic (1). There have been reported cases of osteonecrosis secondary to Covid-19 infection. However, these cases are typically attributed to the steroids used in the treatment plan of the viral infection. Here, we describe a case of idiopathic osteonecrosis attributed to a Covid-19 infection where the patient was not treated with steroids. We discuss a possible relationship between AVN and the cardiovascular system that may reflect an underlying cause contributing to avascular necrosis and Covid-19.

Idiopathic osteonecrosis of the femoral head (INFH) seriously affects patients’ activities and is a heavy burden to society and patients’ families. Therefore, the early diagnosis and treatment of INFH is essential in reducing pain and burden. In the present study, the cancellous bone under the cartilage of the femoral head was isolated from patients with INFH and femoral neck fracture (FNF). Histological examination revealed that the bone trabecular and the medullary cavity in the INFH group compared with those in the FNF group. Whole-transcriptome sequencing (WTS), a recently applied technology, plays a significant role in the screening of risk factors associated with the onset of femoral head necrosis. Herein, WTS was used to obtain the mRNA expression profile in the cancellous bone of the femoral head isolated from 5 patients with INFH and 5 patients with FNF. Compared with the FNF group, a total of 155 differentially expressed genes were identified in the INFH group. Among these genes, 96 and 59 were upregulated and downregulated, respectively. Reverse transcription-quantitative PCR and western blot analyses revealed that leucine-rich repeat-containing 17 (LRRC17) displayed the most significantly decreased mRNA and protein expression levels between the INFH and FNF groups. The expression profile of the differentially expressed genes and LRRC17 protein in the INFH and FNF groups was consistent with that obtained by WTS. LRRC17, a leucine repeat sequence, plays a significant role in regulating bone metabolism, thus indicating that LRRC17 downregulation could affect bone metabolism and could be considered a key factor in the pathogenesis of INFH.

Objective: To investigate the long-term outcomes of minimally invasive Oxford phase Ⅲ unicompartmental knee arthroplasty (UKA) for patients with medial compartment osteoarthropathy. Methods: The clinical data of 594 patients (701 knees) who underwent minimally invasive UKA with Oxford phase Ⅲ unicompartmental prosthesis at Department of Orthopedics,the Affiliated Hospital of Qingdao University from January 2007 to January 2016 were retrospectively analyzed.There were 155 males and 439 females,aged (62.6±10.9) years (range: 44 to 81 years),with a body mass index of (26.9±3.8) kg/m2 (range: 21.1 to 36.2 kg/m2).There were 359 left knees and 342 right knees,676 knees with osteoarthritis and 25 knees with idiopathic osteonecrosis of the medial femoral condyle.There were 487 cases underwent UKA (66 cases underwent UKA on one side and total knee arthroplasty on the other) and 107 cases underwent bilateral UKA.Patients' prosthetic survival,complications,range of motion(ROM) of the knee,visual analogue score (VAS),Western Ontario and McMaster University (WOMAC) osteoarthritis index,and American knee society score (KSS) were collected to assess clinical outcomes.Paired sample t test was used to compare the data before and after operation. Results: All patients completed the surgery successfully.There was no intraoperative fractures,postoperative infections or symptomatic vascular embolic disease occurred.The postoperative complications,including mobile bearing dislocation,prosthesis loosening,tibial plateau collapse,the lateral compartment degeneration and postoperative pain were occurred in 18 cases (3.0%,18/594).Thirteen patients suffered complications were transferred to total knee arthroplasty,4 underwent partial revision,if this was used as the endpoint of the study,the surgical success rate was 97.1% (577/594) and the prosthetic revision rate was 2.9%.The ROM was improved from(105.9±11.8)°preoperatively to (114.0±13.3)° at the last follow-up (t=10.796,P<0.01);the KSS clinical score was increased from 54.3±3.6 to 90.1±6.0 (P<0.01) and the functional score was increased from 55.9±3.9 to 87.5±5.7(t=124.325,P<0.01;t=110.985,P<0.01).The WOMAC osteoarthritis index was decreased from 54.8±6.7 to 9.2±3.1 at the last follow-up(t=150.860,P<0.01) and the VAS was decreased from 6.1±1.1 to 1.5±1.0 at the last follow-up(t=74.941,P<0.01). Conclusions: Minimally invasive Oxford phase Ⅲ UKA for medial compartment knee osteoarthritis has a favorable prosthesis survival rate,low revision rate,and few complications at long-term follow-up.Patients have significant improvement in knee function with satisfactory clinical outcomes.

Hyaluronan (HA) plays crucial roles in the maintenance of high-quality cartilage extracellular matrix. Several studies have reported the HA in synovial fluid in patients with osteoarthritis (OA), but few have described the changes of HA in articular cartilage of OA or idiopathic osteonecrosis of the femoral head (ONFH). KIAA1199 was recently reported to have strong hyaluronidase activity. The aim of this study was to clarify the HA metabolism in OA and ONFH, particularly the involvement of KIAA1199. Immunohistochemical analysis of KIAA1199 and HA deposition was performed for human OA (n = 10), ONFH (n = 10), and control cartilage (n = 7). The concentration and molecular weight (MW) of HA were determined by competitive HA ELISA and Chromatography, respectively. Regarding HA metabolism-related molecules, HAS1, HAS2, HAS3, HYAL1, HYAL2, and KIAA1199 gene expression was assessed by reverse transcriptase polymerase chain reaction. Histological analysis showed the overexpression of KIAA1199 in OA cartilage, which was accompanied by decreased hyaluronic acid binding protein (HABP) staining compared with ONFH and control. Little KIAA1199 expression was observed in cartilage at the collapsed area of ONFH, which was accompanied by a slight decrease in HABPstaining. The messenger RNA (​​​​​mRNA) expression of HAS2 and KIAA1199 was upregulated in OA cartilage, while the mRNA expression of genes related to HA catabolism in ONFH cartilage showed mostly a downward trend. The MWof HA in OA cartilage increased while that in ONFH cartilage decreased. HA metabolism in ONFH is suggested to be generally indolent, and is activated in OA including high expression of KIAA1199. Interestingly, MW of HA in OA cartilage was not reduced.

PurposeThe purpose is to compare the therapeutic efficacy of concentrated autologous bone marrow aspirate transplantation (CABMAT) with that of observation alone for osteonecrosis of the femoral head (ONFH).MethodsThis single-center study included patients with idiopathic ONFH that were either treated with CABMAT (CABMAT group) or managed through observation alone (observation group) over a >2-year follow-up period. The Japanese Investigation Committee classification was used to diagnose and classify ONFH. The collapse rates for stages 1 and 2 ONFH (i.e., pre-collapse stages) and the THA conversion rates were compared between the CABMAT and observation groups.ResultsThe CABMAT and observation groups comprised 232 (mean follow-up: 8.2 years) and 106 (mean follow-up: 6.0 years) patients, respectively. No significant intergroup differences were noted in the stages, types, and associated factors of ONFH. The collapse rates for pre-collapse stages in the CABMAT and observation groups were 67.1% and 65.3%, respectively. For stage 1, the collapse rates were significantly lower in the observation group than in the CABMAT group (p<0.05). The overall THA conversion rates in the CABMAT and observation groups were 24.3% and 41.5%, respectively (p<0.0001). For ONFH of stages 3A and 3B (collapse stages), the THA conversion rates were significantly lower in the CABMAT group (p<0.05).ConclusionCollapse rates were significantly higher for stage 1 ONFH; for collapse stages, the THA conversion rates were significantly lower in the CABMAT group than in the observation group. Therefore, observation and CABMAT are recommended for ONFH of stage 1 and for ONFH of higher stages, respectively.

New alcohol-associated idiopathic osteonecrosis of the femoral head (ONFH) development in the contralateral hip after the alcohol-associated ONFH in the lateral hip. A case report

Legg-Calve-Perthes disease (LCPD) is a known childhood form of idiopathic femoral head osteonecrosis. It is characterized by a sequence of events involving the capital femoral epiphysis. The disease process is associated with the disruption of the blood supply to the femoral head. In most cases, LCPD appears in a sporadic form. Occurrences of cases in families have also been reported, with some families having more than two affected individuals. The disease etiology is still unknown, however, various factors have been considered for the pathogenesis of LCPD, including very low body weight or short stature at birth, maternal smoking, and secondhand smoke exposure. Interaction of multiple environmental and genetic factors has also been postulated as an underlying player in the development of the disorder. Hypercoagulability may have a major role in LCPD development. Families segregating LCPD largely demonstrate autosomal dominant inheritance. Variants in coagulations genes (Factor 5 and Factor 2) and collagen encoding gene (COL2A1) have been linked to the disease. However, our knowledge of the LCPD pathogenic factors is limited. A better understanding of the association between LCPD and causative factors, for example, the role of hypercoagulability in osteonecrosis development, might lead to the development of improved treatments, to shorten the acute phase of the disease during childhood as well as to possibly reduce the long-term effects of osteoarthritis in adulthood. Detection of large-effect variants underlying LCPD may help in offering extended screening for all first-degree family members. In this review, we would like to discuss the etiological factors underlying LCPD with special emphasis on the role of coagulation factors and mutations in the genes encoding those coagulation factors.

BackgroundFemoral neck stress fractures are rare and often recognized as overuse injuries that occur in young athletes or military personnel. A case following osteonecrosis of the femoral head is quite rare; even more uncommon is its occurrence in the bilateral hips. Magnetic resonance imaging has been established as the preferred tool for diagnosing nondisplaced femoral neck stress fracture due to overuse injury. Magnetic resonance imaging was also useful to detect the initial lesion even in this case, although the etiology was different between overuse injury and insufficiency fracture.Case presentationA 41-year-old Japanese woman diagnosed with bilateral early stage idiopathic osteonecrosis of the femoral head was observed non-weight-bearing as much as possible using a stick. However, her pain and difficulty in walking progressed. Bilateral femoral neck stress fractures were subsequently detected by magnetic resonance imaging. The fracture initially appeared as a spot of bone marrow edema at the medial site of the femoral neck, and then developed into a fracture line. The patient underwent internal fixation of both hips with sliding hip screws to stabilize the stress fractures. In addition, the preparatory reaming served as core decompression of the femoral heads, as well as being treatment for osteonecrosis. Her bone mineral density and 25-hydroxy vitamin D values were low for her age. We administered eldecalcitol and teriparatide acetate. Her symptoms mostly improved, and the fracture lines and necrotic lesions on magnetic resonance imaging reduced at 5 months after the surgery.ConclusionsBilateral femoral neck stress fractures are a very rare condition and are often missed. It is important to listen to the patient’s complaints and perform an appropriate examination. We encountered a case of bilateral femoral neck stress fracture that occurred in a patient with early stage osteonecrosis of the femoral head, and were able to observe progression of stress fracture since before fracture occurred. This is considered to be the first report to capture imaging changes before and after the onset.

Objectives In this study, we aimed to investigate whether anatomical variations of acetabulum were associated to idiopathic osteonecrosis (ON) of the femoral head.Patients and methods Between January 2014 and March 2020, a total of 46 patients (32 males, 14 females; mean age: 43 years; range, 18 to 66 years) who were diagnosed with unilateral or bilateral ON of the hip joint and 44 healthy age- and sex-matched controls (30 males, 14 females; mean age: 46 years; range, 18 to 79 years) with no signs of ON of the hip joint were retrospectively analyzed. For both groups, measurements were taken of the anatomic parameters, including the acetabular version angle (VA), the sharp angle (SA), and the center-edge angle (CEA) on anteroposterior pelvic radiographs and magnetic resonance imaging (MRI) scans.Results The mean VA of both hips was found to be significantly smaller in Group 1 than in Group 2 on both MRI and X-ray (14.9±4.1 and 14.4±3.1 vs. 17.3±3.9 and 18.0±3.7, respectively; p=0.004, p<0.001). The mean SA of both hips was found to be significantly smaller in Group 1 than in Group 2 on both MRI and X-ray (39.0±2.9 and 38.9±2.8 vs. 41.6±3.9 and 40.8±4.9, respectively; p=0.001, p=0.036). The mean CEA of both hips was found to be significantly larger in ON group than in control group on both MRI and X-ray (36.7±6.1 and 36.9±7.0 vs. 32.0±6.0 and 31.5±7.5, respectively; p<0.001, p=0.001). Conclusion Version angles were found to be smaller in patients with ON and more acetabular coverage was observed. Greater coverage of the acetabulum may indicate early collapses of the femoral head even in Stage 2 ON patients. The smaller version angles may be associated with ON.

AimsTo investigate whether idiopathic osteonecrosis of the femoral head (ONFH) is related to impaired osteoblast activities.MethodsWe cultured osteoblasts isolated from trabecular bone explants taken from the femoral head and the intertrochanteric region of patients with idiopathic ONFH, or from the intertrochanteric region of patients with osteoarthritis (OA), and compared their viability, mineralization capacity, and secretion of paracrine factors.ResultsOsteoblasts from the intertrochanteric region of patients with ONFH showed lower alkaline phosphatase (ALP) activity and mineralization capacity than osteoblasts from the same skeletal site in age-matched patients with OA, as well as lower messenger RNA (mRNA) levels of genes encoding osteocalcin and bone sialoprotein and higher osteopontin expression. In addition, osteoblasts from patients with ONFH secreted lower osteoprotegerin (OPG) levels than those from patients with OA, resulting in a higher receptor activator of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) ligand (RANKL)-to-OPG ratio. In patients with ONFH, osteoblasts from the femoral head showed reduced viability and mineralized nodule formation compared with osteoblasts from the intertrochanteric region. Notably, the secretion of the pro-resorptive factors interleukin-6 and prostaglandin E2 as well as the RANKL-to-OPG ratio were markedly higher in osteoblast cultures from the femoral head than in those from the intertrochanteric region.ConclusionIdiopathic ONFH is associated with a reduced mineralization capacity of osteoblasts and increased secretion of pro-resorptive factors.Cite this article: Bone Joint Res 2021;10(9):619–628.

Background. LeggCalvePerthes disease (LCPD) is an idiopathic avascular femoral head osteonecrosis. The early disease stage is associated with the development of synovitis of the hip joint linked to the overproduction of factors induced by hypoxia as well as of interleukin (IL)-6. Associations of individual polymorphic variants of cytokine genes with LCPD have been shown. Moreover, alterations in the cytokine regulatory cascade are considered an important link in the pathogenesis of synovial inflammation in the early stages of LCPD. Accordingly, this process may be associated with a certain combination of polymorphic variants of the genes for pro-inflammatory and anti-inflammatory cytokines.&#x0D; Aim. This study aimed to study the associations of polymorphic variants of the genes for pro-inflammatory and anti-inflammatory IL with LCPD.&#x0D; Materials and methods. In this casecontrol study, the main and control groups were composed of 26 children with LCPD and 40 healthy children (all aged 311 years), respectively. Genotyping of IL10 (rs1800896), IL13 (rs20541), IL18 (rs187238), IL18 (rs5744292), IL1a (rs1800587), IL1RA (POL_GF_58), IL-1Ra (rs4251961), IL1B (rs16944), IL1B (rs1143634), IL4 (POL_GF_59), IL4 (rs2243250), IL6 (rs1800796), IL6 (rs1800795), INF (rs2430561), TGF (rs1800469), and TNF (rs1800629) was performed by polymerase chain reaction (PCR) using TaqMan probes to the corresponding polymorphic variants of genes produced by Thermo Fisher Scientific (USA) on an amplifier ViiATM 7 RealTime PCR System (Life Technologies, USA). Statistical processing of the results was carried out using the SNPstats program and multifactor dimensionality reduction.&#x0D; Results. The study revealed three separate LCPD-potentiating genotypes of polymorphic variants of cytokine genes: IL10 (rs1800896; TC)*T/C (OR 6.50), IL4 (POL_GF_49, VNTR, Intron4)*2R/2R (OR 12.32), and IL-6 (rs1800796; GC)*G/C (OR 4.08). Two polymorphic variants of the IL4 gene (POL_GF_49, VNTR, Intron4, and rs2243250; CT) had a pronounced synergism with respect to the diagnosis of LCPD. Moderate synergy with respect to the diagnosis of LCPD demonstrated the intergenic interaction of IL6 (rs1800796, GC) with tumor necrosis factor- (rs1800629, GA). Moderate antagonism between LCPD and intergenic interactions was obtained for polymorphic variants of IL18 (rs5744292, TC) and transforming growth factor- (rs1800469, AG) genes.&#x0D; Conclusions. The pathogenesis of synovitis and subsequent osteonecrosis in LCPD is associated with a combination of polymorphic variants of the genes of pro-inflammatory and anti-inflammatory cytokines, as well as of DNA variants of the pro-allergic IL4 gene.