Efficacy Analysis of HBOT Combined with rhBMP-2 Augmented Cannulated Screw Fixation for Displaced Femoral Neck Fractures in Young Adults

Efficacy Analysis of HBOT Combined with rhBMP-2 Augmented Cannulated Screw Fixation for Displaced Femoral Neck Fractures in Young Adults | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Efficacy Analysis of HBOT Combined with rhBMP-2 Augmented Cannulated Screw Fixation for Displaced Femoral Neck Fractures in Young Adults Tianrun Xue, Sheng Li, Jichao Guo, Xu li, Shuai Tian, Zhiyong Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6465472/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Objective: To investigate the clinical efficacy of HBOT combined with rhBMP-2 assisted cannulated screw fixation in treating displaced femoral neck fractures in young adults. Methods: Eighty patients with displaced femoral neck fractures were enrolled and randomly divided into a treatment group (n=40) and a control group (n=40). Both groups underwent closed reduction and cannulated screw compression internal fixation. The treatment group additionally received intraoperative rhBMP-2 implantation and postoperative HBO therapy. Outcomes compared included operative time, intraoperative blood loss, fracture healing time, nonunion rate, 2-year femoral head necrosis rate, HHS and VAS pain scores Results: Follow-up was completed by 39 patients in the treatment group and 35 in the control group. Baseline characteristics showed no significant differences. Operative time and blood loss were comparable between groups. The treatment group exhibited a nonunion rate of 2.56% vs. 8.57% in the control group, and a femoral head necrosis rate of 5.12% vs. 14.28%, though these differences were not statistically significant. Fracture healing time was significantly shorter in the treatment group (4.21±1.09 vs. 4.71±0.95 months, P<0.05). HHS and VAS scores were significantly better in the treatment group (P<0.05). Conclusion: The combination of HBOT, rhBMP-2, and cannulated screw fixation may represent a favorable therapeutic option. Health sciences/Diseases Health sciences/Diseases/Trauma Femoral neck fractures Cannulated compression screws Recombinant human bone morphogenetic protein-2 Hyperbaric oxygen therapy Figures Figure 1 Figure 2 Figure 3 Background Displaced femoral neck fractures in young adults account for approximately 11% of all femoral neck fractures [1,2], with most cases resulting from high-energy trauma [3]. While closed reduction and internal fixation remain the primary clinical treatment for young patients with femoral neck fractures, two major postoperative complications persist: fracture nonunion and femoral head necrosis. The reported incidence rates range from 10-23% and 15-38% respectively [4-6], significantly higher than those observed in non-displaced femoral neck fractures. These complications remain unresolved to date. Cannulated compression screws, which allow fracture site compression and minimally invasive implantation, are currently the preferred internal fixation devices for femoral neck fractures in clinical practice [7]. Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) [8], a member of the transforming growth factor-beta (TGF-β) superfamily, has been widely used clinically to promote fracture healing. Hyperbaric oxygen therapy (HBOT), known for its ability to enhance local oxygen partial pressure and stimulate tissue regeneration [9], has demonstrated therapeutic potential in various fracture treatments [10,11] and femoral head necrosis management [12]. This prospective study aims to evaluate the clinical efficacy of hyperbaric oxygen therapy combined with cannulated screw fixation in the treatment of displaced femoral neck fractures. Materials and Methods 1. General Data A total of 80 femoral neck fracture patients admitted to the Third Hospital of Hebei Medical University from June 1, 2022, to December 31, 2023, were enrolled as study subjects. Participants were randomly divided into a treatment group (n = 40) and a control group (n = 40) using a random number table. Inclusion Criteria: Age 18–60 years; Unilateral femoral neck fracture; Fracture injury duration <2 weeks; No prior history of femoral neck fractures. Exclusion Criteria: Chronic femoral neck fractures; Pathological fractures; Osteoporotic femoral neck fractures; Concomitant fractures at other sites; Comorbidities including rheumatoid arthritis, congenital hip dysplasia, or preexisting femoral head necrosis; Severe metabolic disorders; Long-term alcohol abuse or corticosteroid use. This study was approved by the Ethics Committee of the Third Hospital of Hebei Medical University (Approval No. K2021-011-1). Written informed consent was obtained from all participants and their families. All clinical data were authorized for publication by the patients. All experiments were performed in accordance with relevant guidelines and regulations. 2. Treatment Protocol Surgical Procedure: All patients underwent closed reduction and internal fixation with cannulated compression screws. Intraoperative fluoroscopy was performed using a G-arm X-ray machine. Fractures were reduced on an orthopedic traction table and fixed with three 7.3-mm cannulated compression screws arranged in an inverted triangular configuration. Adjunctive Therapies: Treatment Group: Intraoperative implantation of rhBMP-2 (0.2mg) ,technique（fig1-4）. Postoperative hyperbaric oxygen therapy (HBOT) initiated on postoperative day 1, administered daily for 10 consecutive days. HBOT Parameters: Multiplace hyperbaric chamber (Model: GY2800-12, air compression). Compression phase: 20 minutes to reach 0.20 MPa. Oxygen delivery: 70 minutes of 100% oxygen via mask at 0.20 MPa, interrupted by a 5-minute air-breathing interval. Decompression phase: 25 minutes to return to ambient pressure. 3. Outcome Measures Intraoperative Metrics:Operativetime;Intraoperative blood loss. Fracture Healing: Healing time;Fracture union rate (monthly follow-up until union). Femoral Head Necrosis:Necrosis rate assessed at 2-year follow-up. Functional Outcomes: Harris Hip Score (HHS): Evaluated at 1, 3, and 6 months postoperatively. Pain Assessment: Visual Analog Scale (VAS) Score: Recorded preoperatively and on postoperative days 1 (pre-HBOT), 5, and 10. 4. Statistical Analysis Data were analyzed using SPSS 27.0. Continuous variables with normal distribution are expressed as mean ± standard deviation（x ̅±s） and group comparisons were performed using independent samples t-tests. Non-normally distributed data are presented as medians with interquartile ranges (IQR) and analyzed via non-parametric tests. Categorical variables are reported as frequencies or percentages (%), with group differences assessed by χ² tests. A P < 0.05 was considered statistically significant. Results A total of 74 patients completed follow-up, including 39 in the treatment group and 35 in the control group. Baseline characteristics such as gender, age, Garden classification, and surgical side showed no statistically significant differences between the two groups (P > 0.05), confirming comparability (Table 1). Table 1. Comparison of Gender, Age, Surgical Side, and Garden Classification Between the Treatment and Control Groups Group Cases Age (years) Gender (M/F) Garden Type SurgicalSide M F III IV Right Left Treatment 39 48.67±8.54 13 26 26 13 20 19 Control 35 46.86±10.92 12 23 26 9 24 11 t/c 2 0.798 0.007 0.513 2.287 P 0.428 0.931 0.474 0.130 1. Operative Time and Intraoperative Blood Loss (Table 2): The treatment group had a mean operative time of 47.12 ± 10.35 minutes and intraoperative blood loss of 14.23 ± 4.52 mL, while the control group exhibited a mean operative time of 43.45 ± 10.45 minutes and blood loss of 12.57 ± 4.43 mL. No statistically significant differences were observed between the two groups in either metric (P > 0.05). 2. Fracture Healing Time, Nonunion Rate, and Femoral Head Necrosis Rate: Treatment Group: Fracture nonunion: 1 case (2.56%); Femoral head necrosis: 2 cases (5.12%). Control Group: Fracture nonunion: 3 cases (8.57%); Femoral head necrosis: 5 cases (14.28%). No statistically significant differences were found in femoral head necrosis or fracture nonunion rates between the groups (P > 0.05). After excluding 3 patients with fracture nonunion, the mean fracture healing time was 4.21 ± 1.09 months in the treatment group versus 4.71 ± 0.95 months in the control group, demonstrating a statistically significant difference (P < 0.05) (Table 2). Table 2: Comparison of operative time, intraoperative blood loss, fracture nonunion, femoral head necrosis, and fracture healing time between the treatment group and the control group 。 Operation time (min) blood loss (ml) Femoral head necrosis Non-union Healing time (months) Treatment（n=39） 47.12±10.35 14.23±4.52 2（5.12%） 1（2.56%） 4.21±1.09（n=38） Control（n=35） 43.45±10.45 12.57±4.43 5（14.28%） 3（8.57%） 4.71±0.95（n=32） t/c 2 1.515 1.592 1.806 1.302 2.047 P 0.134 0.116 0.179 0.254 0.044 3. Harris Hip Score (HHS): No statistically significant difference in preoperative HHS was observed between the two groups (P = 0.784). However, the treatment group demonstrated significantly higher HHS at 1, 3, and 6 months postoperatively compared to the control group, with statistically significant differences (P < 0.05) (Table 3). Table 3. Comparison of Harris Hip Scores (HHS) Between the Treatment and Control Groups HHS Preoperative 1 st Month 3 rd Month 6 th Month Treatment（n=39） 21.07±2.04 77.15±5.33 84.31±5.02 93.15±3.95 Control（n=35） 21.25±2.42 65.94±7.38 76.51±6.76 87.17±5.67 t 0.322 5.557 7.829 6.109 P 0.784 <0.001 <0.001 <0.001 4. Visual Analog Scale (VAS) Scores: No statistically significant differences in VAS scores were observed between the treatment and control groups preoperatively or immediately before postoperative hyperbaric oxygen therapy ( P > 0.05). However, the treatment group demonstrated significantly lower VAS scores (indicating reduced pain) compared to the control group on postoperative days 5 and 10, with statistically significant differences ( P < 0.05) (Table 4). Table 4. Visual Analog Scale (VAS) Scores Between the Treatment and Control Groups VAS Preoperative 1 st Day 5 th Day 10 th Day Treatment（n=39） 6.17±1.39 4.76±1.24 2.76±1.06 1（1,2） Control（n=35） 5.93±1.33 3.48±1.30 1.90±0.90 1（1,1） t 1.414 1.618 2.633 3.193 P 0.162 0.11 0.01 0.02 Discussion Femoral neck fractures are clinically common injuries. Since Smith-Petersen's introduction of the tri-flanged nail in 1931 [13], internal fixation has become the primary treatment for femoral neck fractures. However, due to the absence of periosteum at the joint capsule-enveloped femoral neck region and the limited blood supply to the femoral head, postoperative complications such as fracture nonunion and femoral head necrosis remain prevalent, particularly in displaced fractures where vascular disruption exacerbates ischemia. Over the past nine decades, advancements in internal fixation devices and minimally invasive surgical techniques have evolved, yet these two critical complications persist unresolved. Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2), a member of the transforming growth factor-beta (TGF-β) superfamily, is widely used clinically to promote fracture healing [17,18]. Mechanistically, rhBMP-2 binds to specific transmembrane receptors, triggering receptor activation and phosphorylation. This activates intracellular Smad proteins, which translocate to the nucleus to initiate gene transcription, upregulating osteogenic transcription factors such as Runx2 and Osterix. These factors drive the differentiation of undifferentiated mesenchymal stem cells into chondroblasts and osteoblasts [19], facilitating bone and cartilage development, remodeling, and repair. Furthermore, rhBMP-2 enhances fracture healing through chemotactic recruitment of osteoprogenitor cells and the establishment of a localized osteogenic niche, accelerating callus formation, mineralization, and bone defect repair [20]. Notably, Sun et al. [21] demonstrated the potential of rhBMP-2 in treating femoral head necrosis. In this study, the absence of significant differences in operative time and intraoperative blood loss between the treatment and control groups (P > 0.05) indicates that the additional intraoperative rhBMP-2 implantation did not prolong surgical duration or increase procedural complexity. Hyperbaric oxygen therapy (HBOT), as an emerging therapeutic modality, enhances fracture healing by elevating blood oxygen partial pressure, thereby increasing oxygen diffusion to the fracture site. This promotes osteoblast regeneration and proliferation, accelerating fracture repair [16]. Qi et al. [22] reported favorable clinical outcomes with adjuvant HBOT in femoral neck fractures, while Li et al. [23] demonstrated its efficacy in mitigating femoral head necrosis. Beyond oxygenation, HBOT exerts anti-inflammatory and tissue-reparative effects by enhancing macrophage phagocytic capacity, facilitating necrotic tissue clearance, and reducing inflammatory responses [24]. Additionally, HBOT improves capillary permeability, minimizes exudation, alleviates edema, and decreases intracapsular pressure, collectively contributing to pain reduction. In this study, the treatment group exhibited significantly lower VAS scores on postoperative days 5 and 10 compared to the control group (P < 0.05), with no baseline differences preoperatively or pre-HBOT. This suggests that early HBOT intervention reduces inflammation, mitigates periarticular edema, and relieves hip pain. Early pain alleviation likely facilitates functional recovery, as evidenced by the treatment group’s superior Harris Hip Scores at 1, 3, and 6 months postoperatively. These benefits may arise from a synergistic effect between HBOT’s anti-inflammatory actions and rhBMP-2’s osteoinductive properties, which collectively enhance fracture healing and functional restoration. Cannulated compression screws are widely used in clinical practice for femoral neck fracture fixation [26]. Their anti-rotational stability and interfragmentary compression enhance fracture healing while minimizing iatrogenic disruption to femoral head vasculature during closed reduction, thereby reducing the risk of avascular necrosis. However, in displaced femoral neck fractures, severe soft tissue and vascular damage often lead to persistently high rates of nonunion (10–12.5%) and femoral head necrosis (12.5–13.7%) with screw fixation alone [14,15]. In this study, the control group exhibited comparable complication rates (nonunion: 8.57%; necrosis: 14.28%), underscoring the limitations of standalone screw fixation. While total hip arthroplasty remains an effective solution for elderly patients [25], younger individuals require joint-preserving strategies due to their longer life expectancy and higher functional demands. Although the treatment group demonstrated lower complication rates (nonunion: 2.56%; necrosis: 5.12%) compared to the control group, the differences were not statistically significant (P > 0.05), potentially due to limited sample size, insufficient follow-up duration, or suboptimal HBOT protocol intensity. Notably, the treatment group achieved significantly shorter fracture healing times (4.21 ± 1.09 months vs. 4.71 ± 0.95 months, P < 0.05). This acceleration likely reflects a synergistic effect between rhBMP-2’s osteoinductive properties and HBOT’s anti-inflammatory and pro-angiogenic actions, which collectively enhance early bone regeneration and remodeling. In summary, the combined regimen of hyperbaric oxygen therapy (HBOT), rhBMP-2, and cannulated screw fixation demonstrates efficacy in alleviating early postoperative hip pain, shortening fracture healing time, and accelerating functional recovery in young adults with displaced femoral neck fractures. This multimodal approach represents a promising therapeutic strategy for this patient population, balancing preservation of native hip anatomy with enhanced regenerative outcomes—critical considerations for younger individuals with high functional demands and long-term joint health expectations. Declarations Acknowledgements None. Ethics approval and consent to participate Ethical approval was obtained from the Institutional Ethics Committee of the Third Hospital of Hebei Medical University.( Approval No.: Ke 2024-011-1) Author contributions T.X. and Z.L. designed the experiments and wrote the main manuscript text. T.X. prepared figures 1-8. X. L, X.S. and J.G. performed surgery and collected the data. S.T. analyzed the data. All authors reviewed the manuscript. Funding This study was supported by the S&T Program of Hebei（21377743D） Data availability Data is provided within the manuscript files. The corresponding author can provide the relevant data upon reasonable request. Clinical Trial Number not applicable. Consent for publication All relevant patients provided informed consent for the anonymous use and publication of their clinical data, with signed informed consent forms obtained. Ethics approval and consent to participate The study was approved by the hospital's ethics committee (approval number: K2021-011-1), and informed consent was obtained from all participants and their families. Competing interests All authors have no financial or personal relationships with people or organisations, which could inappropriately influence our work. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6465472","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":465821556,"identity":"fc5a0dfe-594f-46e1-9e99-b209eb722807","order_by":0,"name":"Tianrun Xue","email":"","orcid":"","institution":"Hebei Medical UniversityThird Hospital","correspondingAuthor":false,"prefix":"","firstName":"Tianrun","middleName":"","lastName":"Xue","suffix":""},{"id":465821557,"identity":"e2c45300-63d4-43da-9757-18cdf64c0728","order_by":1,"name":"Sheng Li","email":"","orcid":"","institution":"Hebei Medical UniversityThird Hospital","correspondingAuthor":false,"prefix":"","firstName":"Sheng","middleName":"","lastName":"Li","suffix":""},{"id":465821558,"identity":"0e2d3354-6568-41bc-b854-794f732dac1f","order_by":2,"name":"Jichao Guo","email":"","orcid":"","institution":"Hebei Medical UniversityThird Hospital","correspondingAuthor":false,"prefix":"","firstName":"Jichao","middleName":"","lastName":"Guo","suffix":""},{"id":465821559,"identity":"3c413db6-87a4-41f9-a91c-0b30664a0a74","order_by":3,"name":"Xu li","email":"","orcid":"","institution":"Hebei Medical UniversityThird Hospital","correspondingAuthor":false,"prefix":"","firstName":"Xu","middleName":"","lastName":"li","suffix":""},{"id":465821560,"identity":"34783b1c-cd2e-424f-a3b1-33efb78977a0","order_by":4,"name":"Shuai Tian","email":"","orcid":"","institution":"Hebei Medical UniversityThird Hospital","correspondingAuthor":false,"prefix":"","firstName":"Shuai","middleName":"","lastName":"Tian","suffix":""},{"id":465821561,"identity":"6efd2740-9d23-4a29-aad2-68c9d26933a8","order_by":5,"name":"Zhiyong Li","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA5ElEQVRIiWNgGAWjYBACefbGhgMJPDY8/BIMbBChAwS0GPYcPvjgg0yajOQMYrUw3EhLNpxhc9jG4AaxWhh7zphJ8+Qc5jG+3Xzs0c02Bjm+GwmMnwvwaGFn7wFqOZPOY3bnWLpxbhuDseSNBGbpGYRs4e2x5jG7kWMmDdSSuOFGAhszD16/AFXy/mPmMZ6R/w2kpZ4ILSDv8zjzGEjksIG0JBgQ0gIJZJ40HokbaebGOeckDGeeedgsjU8LLCrt+WckP3ucU2Yjz3c8+eBnvA5DAxJAzNhAgoZRMApGwSgYBdgAABV2TPL+4W7dAAAAAElFTkSuQmCC","orcid":"","institution":"Hebei Medical UniversityThird Hospital","correspondingAuthor":true,"prefix":"","firstName":"Zhiyong","middleName":"","lastName":"Li","suffix":""}],"badges":[],"createdAt":"2025-04-16 16:53:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6465472/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6465472/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":84188151,"identity":"d47460cd-d734-4568-a78f-8b4e6f38131a","added_by":"auto","created_at":"2025-06-09 06:06:28","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":400554,"visible":true,"origin":"","legend":"\u003cp\u003eA simplified cannulated screw tunnel implantation technique, characterized by its minimal invasiveness and operational ease, has been preliminarily applied in clinical practice. Under fluoroscopic guidance, three 2.5-mm guidewires are inserted parallel to the femoral neck axis from below the greater trochanter in an inverted triangular configuration. One guidewire is strategically positioned through the most comminuted fracture zone based on preoperative CT 3D reconstruction, with its tip maintained 5 mm from the femoral head cartilage. Three 0.5-cm skin incisions are created along the guidewires, followed by cannulated drilling to a depth beyond the fracture line. Two cannulated screws are first implanted along the intact fracture-side guidewires. Subsequently, rhBMP-2 strips are packed into the third cannulated screw, and the original 2.5-mm guidewire is replaced with a 0.5-mm guidewire. The third screw is advanced along the 0.5-mm guidewire until reaching the fracture site. The thinner guidewire is then removed, and a 2.5-mm guidewire is inserted retrograde through the screw’s cannula to deliver rhBMP-2 directly into the fracture gap. Finally, the third screw is fully tightened to complete the fixation. This technique integrates targeted biologics delivery with biomechanical stability without additional trauma, demonstrating promising clinical feasibility.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6465472/v1/c2cf823f073e13c1fbd769c0.png"},{"id":84186956,"identity":"335c10cb-1efa-4a97-be56-e2f3380ed209","added_by":"auto","created_at":"2025-06-09 05:42:21","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":211258,"visible":true,"origin":"","legend":"\u003cp\u003eA\u0026amp; Figure 2B：A 38-year-old male sustained a right-sided femoral neck fracture (Garden IV type) due to a fall. He was treated with hyperbaric oxygen therapy (HBOT) combined with rhBMP-2-augmented cannulated screw fixation, achieving complete fracture union at 3 months postoperatively.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6465472/v1/80080bfefa38507dba058816.png"},{"id":84186955,"identity":"d56f9fb4-0c9b-4b08-92e5-8f8a508f2d0b","added_by":"auto","created_at":"2025-06-09 05:42:21","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":263172,"visible":true,"origin":"","legend":"\u003cp\u003eA\u0026amp; Figure 3B：A 49-year-old female sustained a right femoral neck fracture (Garden III type) secondary to a motor vehicle accident. She underwent hyperbaric oxygen therapy (HBOT) combined with rhBMP-2-augmented cannulated screw fixation, achieving uneventful fracture union. At the 2-year postoperative follow-up, imaging revealed normal femoral head morphology with no signs of avascular necrosis.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6465472/v1/dab698dbcfac73157c2be0e7.png"},{"id":84188152,"identity":"a417f5f0-27fb-470a-b31b-f3625b676f50","added_by":"auto","created_at":"2025-06-09 06:06:33","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1915913,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6465472/v1/d0893d3b-5395-48b1-ae18-4957c15a7584.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Efficacy Analysis of HBOT Combined with rhBMP-2 Augmented Cannulated Screw Fixation for Displaced Femoral Neck Fractures in Young Adults","fulltext":[{"header":"Background","content":"\u003cp\u003eDisplaced femoral neck fractures in young adults account for approximately 11% of all femoral neck fractures [1,2], with most cases resulting from high-energy trauma [3]. While closed reduction and internal fixation remain the primary clinical treatment for young patients with femoral neck fractures, two major postoperative complications persist: fracture nonunion and femoral head necrosis. The reported incidence rates range from 10-23% and 15-38% respectively [4-6], significantly higher than those observed in non-displaced femoral neck fractures. These complications remain unresolved to date.\u003c/p\u003e\n\u003cp\u003eCannulated compression screws, which allow fracture site compression and minimally invasive implantation, are currently the preferred internal fixation devices for femoral neck fractures in clinical practice [7]. Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2) [8], a member of the transforming growth factor-beta (TGF-β) superfamily, has been widely used clinically to promote fracture healing. Hyperbaric oxygen therapy (HBOT), known for its ability to enhance local oxygen partial pressure and stimulate tissue regeneration [9], has demonstrated therapeutic potential in various fracture treatments [10,11] and femoral head necrosis management [12].\u003c/p\u003e\n\u003cp\u003eThis prospective study aims to evaluate the clinical efficacy of hyperbaric oxygen therapy combined with cannulated screw fixation in the treatment of displaced femoral neck fractures.\u003c/p\u003e"},{"header":"Materials and Methods","content":"\u003cp\u003e\u003cstrong\u003e1. General Data\u003cbr\u003e\u0026nbsp;\u003c/strong\u003eA total of 80 femoral neck fracture patients admitted to the Third Hospital of Hebei Medical University from June 1, 2022, to December 31, 2023, were enrolled as study subjects. Participants were randomly divided into a\u0026nbsp;treatment group\u0026nbsp;(n\u0026nbsp;= 40) and a\u0026nbsp;control group\u0026nbsp;(n\u0026nbsp;= 40) using a random number table.\u003c/p\u003e\n\u003cp\u003eInclusion Criteria:\u003c/p\u003e\n\u003cp\u003eAge 18–60 years;\u003c/p\u003e\n\u003cp\u003eUnilateral femoral neck fracture;\u003c/p\u003e\n\u003cp\u003eFracture injury duration \u0026lt;2 weeks;\u003c/p\u003e\n\u003cp\u003eNo prior history of femoral neck fractures.\u003c/p\u003e\n\u003cp\u003eExclusion Criteria:\u003c/p\u003e\n\u003cp\u003eChronic femoral neck fractures;\u003c/p\u003e\n\u003cp\u003ePathological fractures;\u003c/p\u003e\n\u003cp\u003eOsteoporotic femoral neck fractures;\u003c/p\u003e\n\u003cp\u003eConcomitant fractures at other sites;\u003c/p\u003e\n\u003cp\u003eComorbidities including rheumatoid arthritis, congenital hip dysplasia, or preexisting femoral head necrosis;\u003c/p\u003e\n\u003cp\u003eSevere metabolic disorders;\u003c/p\u003e\n\u003cp\u003eLong-term alcohol abuse or corticosteroid use.\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of the Third Hospital of Hebei Medical University (Approval No. K2021-011-1). Written informed consent was obtained from all participants and their families. All clinical data were authorized for publication by the patients. All experiments were performed in accordance with relevant guidelines and regulations.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2. Treatment Protocol\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eSurgical Procedure:\u003c/p\u003e\n\u003cp\u003eAll patients underwent closed reduction and internal fixation with cannulated compression screws. Intraoperative fluoroscopy was performed using a G-arm X-ray machine. Fractures were reduced on an orthopedic traction table and fixed with three 7.3-mm cannulated compression screws arranged in an inverted triangular configuration.\u003c/p\u003e\n\u003cp\u003eAdjunctive Therapies:\u003c/p\u003e\n\u003cp\u003eTreatment Group:\u003c/p\u003e\n\u003cp\u003eIntraoperative implantation of rhBMP-2 (0.2mg) ,technique（fig1-4）.\u003c/p\u003e\n\u003cp\u003ePostoperative hyperbaric oxygen therapy (HBOT) initiated on postoperative day 1, administered daily for 10 consecutive days.\u003c/p\u003e\n\u003cp\u003eHBOT Parameters:\u003c/p\u003e\n\u003cp\u003eMultiplace hyperbaric chamber (Model: GY2800-12, air compression).\u003c/p\u003e\n\u003cp\u003eCompression phase: 20 minutes to reach 0.20 MPa.\u003c/p\u003e\n\u003cp\u003eOxygen delivery: 70 minutes of 100% oxygen via mask at 0.20 MPa, interrupted by a 5-minute air-breathing interval.\u003c/p\u003e\n\u003cp\u003eDecompression phase: 25 minutes to return to ambient pressure.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e3. Outcome Measures\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIntraoperative Metrics:Operativetime;Intraoperative blood loss.\u003c/p\u003e\n\u003cp\u003eFracture Healing:\u003c/p\u003e\n\u003cp\u003eHealing time;Fracture union rate (monthly follow-up until union).\u003c/p\u003e\n\u003cp\u003eFemoral Head Necrosis:Necrosis rate assessed at 2-year follow-up.\u003c/p\u003e\n\u003cp\u003eFunctional Outcomes:\u003c/p\u003e\n\u003cp\u003eHarris Hip Score (HHS): Evaluated at 1, 3, and 6 months postoperatively.\u003c/p\u003e\n\u003cp\u003ePain Assessment:\u003c/p\u003e\n\u003cp\u003eVisual Analog Scale (VAS) Score: Recorded preoperatively and on postoperative days 1 (pre-HBOT), 5, and 10.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e4. Statistical Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData were analyzed using SPSS 27.0. Continuous variables with normal distribution are expressed as mean ± standard deviation（x ̅±s）\u0026nbsp;and group comparisons were performed using independent samples t-tests. Non-normally distributed data are presented as medians with interquartile ranges (IQR) and analyzed via non-parametric tests. Categorical variables are reported as frequencies or percentages (%), with group differences assessed by χ² tests. A P \u0026lt; 0.05 was considered statistically significant.\u0026nbsp;\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eA total of 74 patients completed follow-up, including 39 in the treatment group and 35 in the control group. Baseline characteristics such as gender, age, Garden classification, and surgical side showed no statistically significant differences between the two groups (P \u0026gt; 0.05), confirming comparability (Table 1).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1. Comparison of Gender, Age, Surgical Side, and Garden Classification Between the Treatment and Control Groups\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"100%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 12.4586%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGroup\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 7.5835%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCases\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAge (years)\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 9.8405%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGender (M/F)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd rowspan=\"2\" valign=\"top\" style=\"width: 1.625%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 10.1113%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGarden \u0026nbsp;Type\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 1.625%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 15.6184%;\"\u003e\n \u003cp\u003eSurgicalSide\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 4.9654%;\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 4.9654%;\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 4.6946%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIII\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 5.4168%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eIV\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 1.625%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 8.8474%;\"\u003e\n \u003cp\u003eRight\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 6.6807%;\"\u003e\n \u003cp\u003eLeft\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 12.4586%;\"\u003e\n \u003cp\u003eTreatment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7.5835%;\"\u003e\n \u003cp\u003e39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e48.67\u0026plusmn;8.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 4.9654%;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 4.9654%;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 1.625%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 4.6946%;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 5.4168%;\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 1.625%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 8.8474%;\"\u003e\n \u003cp\u003e20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 6.6807%;\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 12.4586%;\"\u003e\n \u003cp\u003eControl\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7.5835%;\"\u003e\n \u003cp\u003e35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 16px;\"\u003e\n \u003cp\u003e46.86\u0026plusmn;10.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 4.9654%;\"\u003e\n \u003cp\u003e12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 4.9654%;\"\u003e\n \u003cp\u003e23\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 1.625%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 4.6946%;\"\u003e\n \u003cp\u003e26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 5.4168%;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 1.625%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 8.8474%;\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 6.6807%;\"\u003e\n \u003cp\u003e11\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 12.4586%;\"\u003e\n \u003cp\u003et/c\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7.5835%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 12.4586%;\"\u003e\n \u003cp\u003e0.798\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 11.5558%;\"\u003e\n \u003cp\u003e0.007\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 11.7364%;\"\u003e\n \u003cp\u003e0.513\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 15.6184%;\"\u003e\n \u003cp\u003e2.287\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 12.4586%;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 7.5835%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 12.4586%;\"\u003e\n \u003cp\u003e0.428\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 11.5558%;\"\u003e\n \u003cp\u003e0.931\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"3\" valign=\"top\" style=\"width: 11.7364%;\"\u003e\n \u003cp\u003e0.474\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd colspan=\"2\" valign=\"top\" style=\"width: 15.6184%;\"\u003e\n \u003cp\u003e0.130\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e1. Operative Time and Intraoperative Blood Loss (Table 2):\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe treatment group had a mean operative time of 47.12 \u0026plusmn; 10.35 minutes and intraoperative blood loss of 14.23 \u0026plusmn; 4.52 mL, while the control group exhibited a mean operative time of 43.45 \u0026plusmn; 10.45 minutes and blood loss of 12.57 \u0026plusmn; 4.43 mL. No statistically significant differences were observed between the two groups in either metric (P \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2. Fracture Healing Time, Nonunion Rate, and Femoral Head Necrosis Rate:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTreatment Group:\u003c/p\u003e\n\u003cp\u003eFracture nonunion: 1 case (2.56%);\u003c/p\u003e\n\u003cp\u003eFemoral head necrosis: 2 cases (5.12%).\u003c/p\u003e\n\u003cp\u003eControl Group:\u003c/p\u003e\n\u003cp\u003eFracture nonunion: 3 cases (8.57%);\u003c/p\u003e\n\u003cp\u003eFemoral head necrosis: 5 cases (14.28%).\u003c/p\u003e\n\u003cp\u003eNo statistically significant differences were found in femoral head necrosis or fracture nonunion rates between the groups (P \u0026gt; 0.05).\u003c/p\u003e\n\u003cp\u003eAfter excluding 3 patients with fracture nonunion, the mean fracture healing time was 4.21 \u0026plusmn; 1.09 months in the treatment group versus 4.71 \u0026plusmn; 0.95 months in the control group, demonstrating a statistically significant difference (P \u0026lt; 0.05) (Table 2).\u003c/p\u003e\n\u003cp\u003eTable 2:\u0026nbsp;\u003cstrong\u003eComparison of operative time, intraoperative blood loss, fracture nonunion, femoral head necrosis, and fracture healing time between the treatment group and the control group\u003c/strong\u003e\u003cstrong\u003e。\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eOperation time (min)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003eblood loss (ml)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003eFemoral head necrosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003eNon-union\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003eHealing time (months)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003eTreatment（n=39）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e47.12\u0026plusmn;10.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e14.23\u0026plusmn;4.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e2（5.12%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e1（2.56%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e4.21\u0026plusmn;1.09（n=38）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003eControl（n=35）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e43.45\u0026plusmn;10.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e12.57\u0026plusmn;4.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e5（14.28%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e3（8.57%）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e4.71\u0026plusmn;0.95（n=32）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003et/c\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e1.515\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e1.592\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1.806\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e1.302\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e2.047\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0.134\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 70px;\"\u003e\n \u003cp\u003e0.116\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 138px;\"\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 0.179\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 75px;\"\u003e\n \u003cp\u003e0.254\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 140px;\"\u003e\n \u003cp\u003e0.044\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003e3. Harris Hip Score (HHS):\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo statistically significant difference in preoperative HHS was observed between the two groups (P = 0.784). However, the treatment group demonstrated significantly higher HHS at 1, 3, and 6 months postoperatively compared to the control group, with statistically significant differences (P \u0026lt; 0.05) (Table 3).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3. Comparison of Harris Hip Scores (HHS) Between the Treatment and Control Groups\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 92px;\"\u003e\n \u003cp\u003eHHS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreoperative\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e1\u003csup\u003est\u003c/sup\u003e Month\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e3\u003csup\u003erd\u003c/sup\u003e Month\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e6\u003csup\u003eth\u003c/sup\u003e Month\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 92px;\"\u003e\n \u003cp\u003eTreatment（n=39）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e21.07\u0026plusmn;2.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e77.15\u0026plusmn;5.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e84.31\u0026plusmn;5.02\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e93.15\u0026plusmn;3.95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 92px;\"\u003e\n \u003cp\u003eControl（n=35）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e21.25\u0026plusmn;2.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e65.94\u0026plusmn;7.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e76.51\u0026plusmn;6.76\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e87.17\u0026plusmn;5.67\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 92px;\"\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e0.322\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e5.557\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e7.829\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e6.109\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 92px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e0.784\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 104px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e4. Visual Analog Scale (VAS) Scores:\u003c/p\u003e\n\u003cp\u003eNo statistically significant differences in VAS scores were observed between the treatment and control groups preoperatively or immediately before postoperative hyperbaric oxygen therapy (\u003cem\u003eP\u003c/em\u003e \u0026gt; 0.05). However, the treatment group demonstrated \u003cstrong\u003esignificantly lower VAS scores\u003c/strong\u003e (indicating reduced pain) compared to the control group on postoperative days 5 and 10, with \u003cstrong\u003estatistically significant differences\u003c/strong\u003e (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05) (Table 4).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4. Visual Analog Scale (VAS) Scores Between the Treatment and Control Groups\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"101%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eVAS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePreoperative\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1\u003csup\u003est\u003c/sup\u003eDay\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e5\u003csup\u003eth\u003c/sup\u003e Day\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e10\u003csup\u003eth\u003c/sup\u003e Day\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eTreatment（n=39）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e6.17\u0026plusmn;1.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e4.76\u0026plusmn;1.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e2.76\u0026plusmn;1.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1（1,2）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003eControl（n=35）\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e5.93\u0026plusmn;1.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e3.48\u0026plusmn;1.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.90\u0026plusmn;0.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1（1,1）\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.414\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e1.618\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e2.633\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e3.193\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e0.162\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e0.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e0.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 20px;\"\u003e\n \u003cp\u003e0.02\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Discussion","content":"\u003cp\u003eFemoral neck fractures are clinically common injuries. Since Smith-Petersen's introduction of the tri-flanged nail in 1931 [13], internal fixation has become the primary treatment for femoral neck fractures. However, due to the absence of periosteum at the joint capsule-enveloped femoral neck region and the limited blood supply to the femoral head, postoperative complications such as fracture nonunion and femoral head necrosis remain prevalent, particularly in displaced fractures where vascular disruption exacerbates ischemia. Over the past nine decades, advancements in internal fixation devices and minimally invasive surgical techniques have evolved, yet these two critical complications persist unresolved.\u003c/p\u003e\n\u003cp\u003eRecombinant Human Bone Morphogenetic Protein-2 (rhBMP-2), a member of the transforming growth factor-beta (TGF-β) superfamily, is widely used clinically to promote fracture healing [17,18]. Mechanistically, rhBMP-2 binds to specific transmembrane receptors, triggering receptor activation and phosphorylation. This activates intracellular Smad proteins, which translocate to the nucleus to initiate gene transcription, upregulating osteogenic transcription factors such as Runx2 and Osterix. These factors drive the differentiation of undifferentiated mesenchymal stem cells into chondroblasts and osteoblasts [19], facilitating bone and cartilage development, remodeling, and repair.\u003c/p\u003e\n\u003cp\u003eFurthermore, rhBMP-2 enhances fracture healing through chemotactic recruitment of osteoprogenitor cells and the establishment of a localized osteogenic niche, accelerating callus formation, mineralization, and bone defect repair [20]. Notably, Sun et al. [21] demonstrated the potential of rhBMP-2 in treating femoral head necrosis.\u003c/p\u003e\n\u003cp\u003eIn this study, the absence of significant differences in operative time and intraoperative blood loss between the treatment and control groups (P \u0026gt; 0.05) indicates that the additional intraoperative rhBMP-2 implantation did not prolong surgical duration or increase procedural complexity.\u003c/p\u003e\n\u003cp\u003eHyperbaric oxygen therapy (HBOT), as an emerging therapeutic modality, enhances fracture healing by elevating blood oxygen partial pressure, thereby increasing oxygen diffusion to the fracture site. This promotes osteoblast regeneration and proliferation, accelerating fracture repair [16]. Qi et al. [22] reported favorable clinical outcomes with adjuvant HBOT in femoral neck fractures, while Li et al. [23] demonstrated its efficacy in mitigating femoral head necrosis.\u003c/p\u003e\n\u003cp\u003eBeyond oxygenation, HBOT exerts anti-inflammatory and tissue-reparative effects by enhancing macrophage phagocytic capacity, facilitating necrotic tissue clearance, and reducing inflammatory responses [24]. Additionally, HBOT improves capillary permeability, minimizes exudation, alleviates edema, and decreases intracapsular pressure, collectively contributing to pain reduction.\u003c/p\u003e\n\u003cp\u003eIn this study, the treatment group exhibited significantly lower VAS scores on postoperative days 5 and 10 compared to the control group (P \u0026lt; 0.05), with no baseline differences preoperatively or pre-HBOT. This suggests that early HBOT intervention reduces inflammation, mitigates periarticular edema, and relieves hip pain. Early pain alleviation likely facilitates functional recovery, as evidenced by the treatment group’s superior Harris Hip Scores at 1, 3, and 6 months postoperatively. These benefits may arise from a synergistic effect between HBOT’s anti-inflammatory actions and rhBMP-2’s osteoinductive properties, which collectively enhance fracture healing and functional restoration.\u003c/p\u003e\n\u003cp\u003eCannulated compression screws are widely used in clinical practice for femoral neck fracture fixation [26]. Their anti-rotational stability and interfragmentary compression enhance fracture healing while minimizing iatrogenic disruption to femoral head vasculature during closed reduction, thereby reducing the risk of avascular necrosis. However, in displaced femoral neck fractures, severe soft tissue and vascular damage often lead to persistently high rates of nonunion (10–12.5%) and femoral head necrosis (12.5–13.7%) with screw fixation alone [14,15]. In this study, the control group exhibited comparable complication rates (nonunion: 8.57%; necrosis: 14.28%), underscoring the limitations of standalone screw fixation.\u003c/p\u003e\n\u003cp\u003eWhile total hip arthroplasty remains an effective solution for elderly patients [25], younger individuals require joint-preserving strategies due to their longer life expectancy and higher functional demands. Although the treatment group demonstrated lower complication rates (nonunion: 2.56%; necrosis: 5.12%) compared to the control group, the differences were not statistically significant (P \u0026gt; 0.05), potentially due to limited sample size, insufficient follow-up duration, or suboptimal HBOT protocol intensity.\u003c/p\u003e\n\u003cp\u003eNotably, the treatment group achieved significantly shorter fracture healing times (4.21 ± 1.09 months vs. 4.71 ± 0.95 months, P \u0026lt; 0.05). This acceleration likely reflects a synergistic effect between rhBMP-2’s osteoinductive properties and HBOT’s anti-inflammatory and pro-angiogenic actions, which collectively enhance early bone regeneration and remodeling.\u003c/p\u003e\n\u003cp\u003eIn summary, the combined regimen of hyperbaric oxygen therapy (HBOT), rhBMP-2, and cannulated screw fixation demonstrates efficacy in alleviating early postoperative hip pain, shortening fracture healing time, and accelerating functional recovery in young adults with displaced femoral neck fractures. This multimodal approach represents a promising therapeutic strategy for this patient population, balancing preservation of native hip anatomy with enhanced regenerative outcomes—critical considerations for younger individuals with high functional demands and long-term joint health expectations.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eEthical approval was obtained from the Institutional Ethics Committee of the Third Hospital of Hebei Medical University.(\u0026nbsp;Approval No.: Ke 2024-011-1)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eT.X. and Z.L. designed the experiments and wrote the main manuscript text. T.X. prepared figures 1-8. X. L, X.S. and J.G. performed surgery and collected the data. S.T. analyzed the data. All authors reviewed the manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was supported by the S\u0026amp;T Program of Hebei（21377743D）\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData is provided within the manuscript files. The corresponding author can provide the relevant data upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical Trial Number\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003enot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll relevant patients provided informed consent for the anonymous use and publication of\u0026nbsp;\u003c/p\u003e\n\u003cp\u003etheir clinical data, with signed informed consent forms obtained.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe study was approved by the hospital\u0026apos;s ethics committee (approval number: K2021-011-1), and informed consent was obtained from all participants and their families.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll authors have no financial or personal relationships with people or organisations, which could inappropriately influence our work. All authors have read and contributed to the submitted manuscript\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor details\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cem\u003eAll Authors are from Hebei Medical University Third Hospital, Shijiazhuang, Hebei Province\u003c/em\u003e\u003cem\u003e，\u003c/em\u003e\u003cem\u003eChina\u003c/em\u003e\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eJonas Sundkvist,AndersBr\u0026uuml;ggeman,Arkan S. Sayed-Noor,MichaelM\u0026ouml;ller,Olof Wolf, \u0026amp; Sebastian Mukka (2021). Epidemiology, classification, treatment, and mortality of adult femoral neck and basicervical fractures: an observational study of 40,049 fractures from the Swedish Fracture Register. 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PLOS ONE, 9 (6), e100424-e100424. https://doi.org/10.1371/journal.pone.0100424\u003c/li\u003e\n\u003cli\u003eLing, Q., Chengwei, W., Lubing, L., Gulisumuayi\u0026bull;Hujia, Paerhati\u0026bull;Wahefu, Hui, Z.,... Fei, L. (2018). Comparative study on the clinical efficacy of hyperbaric oxygen in the treatment of femoral neck fracture. Chinese Journal of Bone and Joint Surgery, 11(5), 360-363.https://doi.org/10.3969/j.issn.2095-9958.2018.05.010\u003c/li\u003e\n\u003cli\u003eWei Li,ZiliangYe,WeiWang,KunWang,Lang Li, \u0026amp; Dewei Zhao (2016). Clinical effect of hyperbaric oxygen therapy in the treatment of femoral head necrosis. Orthopade, 46 (5), 440-446. https://doi.org/10.1007/s00132-016-3360-8\u003c/li\u003e\n\u003cli\u003eO. Blanco Carballo,Matthew M. Hall,Larry Phillips, \u0026amp; Ronald Lyman (2019). The Effects of Hyperbaric Oxygen Therapy on Edema after Stifle Surgery. Veterinary and Comparative Orthopaedics and Traumatology, 0 (0), 0-0. https://doi.org/10.1055/s-0039-1692282\u003c/li\u003e\n\u003cli\u003eB. Mohan Choudhary, \u0026amp; Ganesan G. Ram (2020). Bipolar hemiarthroplasty versus total hip replacement in displaced femoral neck fracture in elderly. Bhopal, 6 (2), 105-109. https://doi.org/10.17511/ijoso.2020.i02.07\u003c/li\u003e\n\u003cli\u003e\u0026amp; Hao Jiangfen (2013). Study on biomechanics of dynamic hip screw versus cannulated compression screws in treatment of femoral neck fracture. Journal of Shanxi Medical University, 0 (0), 0-0. https://doi.org/null\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Femoral neck fractures, Cannulated compression screws, Recombinant human bone morphogenetic protein-2, Hyperbaric oxygen therapy","lastPublishedDoi":"10.21203/rs.3.rs-6465472/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6465472/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjective: \u003c/strong\u003eTo investigate the clinical efficacy of HBOT combined with rhBMP-2 assisted cannulated screw fixation in treating displaced femoral neck fractures in young adults.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eEighty patients with displaced femoral neck fractures were enrolled and randomly divided into a treatment group (n=40) and a control group (n=40). Both groups underwent closed reduction and cannulated screw compression internal fixation. The treatment group additionally received intraoperative rhBMP-2 implantation and postoperative HBO therapy. Outcomes compared included operative time, intraoperative blood loss, fracture healing time, nonunion rate, 2-year femoral head necrosis rate, HHS and VAS pain scores\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003eFollow-up was completed by 39 patients in the treatment group and 35 in the control group. Baseline characteristics showed no significant differences. Operative time and blood loss were comparable between groups. The treatment group exhibited a nonunion rate of 2.56% vs. 8.57% in the control group, and a femoral head necrosis rate of 5.12% vs. 14.28%, though these differences were not statistically significant. Fracture healing time was significantly shorter in the treatment group (4.21±1.09 vs. 4.71±0.95 months, P\u0026lt;0.05). HHS and VAS scores were significantly better in the treatment group (P\u0026lt;0.05).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eThe combination of HBOT, rhBMP-2, and cannulated screw fixation may represent a favorable therapeutic option.\u003c/p\u003e","manuscriptTitle":"Efficacy Analysis of HBOT Combined with rhBMP-2 Augmented Cannulated Screw Fixation for Displaced Femoral Neck Fractures in Young Adults","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-06-09 05:42:17","doi":"10.21203/rs.3.rs-6465472/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"97c5797b-9f94-40d1-8457-d418d90f8bc9","owner":[],"postedDate":"June 9th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":49452132,"name":"Health sciences/Diseases"},{"id":49452133,"name":"Health sciences/Diseases/Trauma"}],"tags":[],"updatedAt":"2025-06-09T05:42:19+00:00","versionOfRecord":[],"versionCreatedAt":"2025-06-09 05:42:17","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6465472","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6465472","identity":"rs-6465472","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}