Traditional Chinese spinal orthopedic manipulation

Traditional Chinese spinal orthopedic manipulation(TCSOM)is an external therapeutic method of traumatology and orthopedics of traditional Chinese medicine to treat trauma and set bone.The doctor exerts his force through thumb or bilateral upper extremities on the spine or acupoints of the patient,applying various manipulatory techniques according to the conditions.Correcting the abnormal position or state of the spine serve as the most important theoretical foundation for TCSOM to treat spinal disorders and spinogenic disorders.This paper presented the definition and function of the TCSOM,with a special focus on how to make a preliminary diagnosis of spinal segments disorders,and the indications of TCSOM in different spinal segments.

Spinal epidural hematoma after spinal manipulation therapy:Report of three cases and a literature review

BACKGROUND Spinal manipulation therapy(SMT)has been widely used worldwide to treat musculoskeletal diseases,but it can cause serious adverse events.Spinal epidural hematoma(SEH)caused by SMT is a rare emergency that can cause neurological dysfunction.We herein report three cases of SEH after SMT.CASE SUMMARY The first case was a 30-year-old woman who experienced neck pain and numbness in both upper limbs immediately after SMT.Her symptoms persisted after 3 d of conservative treatment,and she was admitted to our hospital.Magnetic resonance imaging(MRI)demonstrated an SEH,extending from C6 to C7.The second case was a 55-year-old man with sudden back pain 1 d after SMT,numbness in both lower limbs,an inability to stand or walk,and difficulty urinating.MRI revealed an SEH,extending from T1 to T3.The third case was a 28-year-old man who suddenly developed symptoms of numbness in both lower limbs 4 h after SMT.He was unable to stand or walk and experienced mild back pain.MRI revealed an SEH,extending from T1 to T2.All three patients underwent surgery after failed conservative treatment.The three cases recovered to ASIA grade E on day 5,1 wk,and day 10 after surgery,respectively.All patients returned to normal after 3 mo of follow-up.CONCLUSION SEH caused by SMT is very rare,and the condition of each patient should be evaluated in full detail before operation.SEH should be diagnosed immediately and actively treated by surgery.

Reduction in nerve root compression by the nucleus pulposus after Feng's Spinal Manipulation

Ninety-four patients with lumbar intervertebral disc herniation were enrolled in this study. Of these, 48 were treated with Feng＇s Spinal Manipulation, hot fomentation, and bed rest （treatment group）. The remaining 46 patients were treated with hot fomentation and bed rest only （control group）. After 3 weeks of treatment, clinical parameters including the angle of straight-leg raising, visual analogue scale pain score, and Japanese Orthopaedic Association score for low back pain were improved. The treatment group had significantly better improvement in scores than the control group. Magnetic resonance myelography three-dimensional reconstruction imaging of the vertebral canal demonstrated that filling of the compressed nerve root sleeve with cerebrospinal fluid increased significantly in the treatment group. The diameter of the nerve root sleeve was significantly larger in the treatment group than in the control group. However, the sagittal diameter index of the herniated nucleus pulposus and the angle between the nerve root sleeve and the thecal sac did not change significantly in either the treatment or control groups. The effectiveness of Feng＇s Spinal Manipulation for the treatment of symptoms associated with lumbar intervertebral disc herniation may be attributable to the relief of nerve root compression, without affecting the herniated nucleus pulposus or changing the morphology or position of the nerve root.

Dietary manipulation and testosterone replacement therapy may explain changes in body composition after spinal cord injury: A retrospective case report

BACKGROUND Reduced level of physical activity,high-fat diet and skeletal muscle atrophy are key factors that are likely to contribute to deleterious changes in body composition and metabolic following spinal cord injury (SCI).Reduced caloric intake with lowering percentage macronutrients of fat and increasing protein intake may likely to improve body composition parameters and decrease ectopic adiposity after SCI.AIM To highlight the effects of dietary manipulation and testosterone replacement therapy (TRT) on body composition after SCI METHODS A 31-year-old male with T5 SCI was administered transdermal TRT daily for 16 wk.Caloric intake and percentage macronutrients were analyzed using dietary recalls.Magnetic resonance imaging and dual-energy x-ray absorptiometry were used to measure changes in body composition.RESULTS Caloric intake and fat percentage were reduced by 445 kcal/d and 6.5%,respectively.Total body weight decreased by 8%,body fat decreased by 29%,and lean mass increased by 7%.Thigh subcutaneous adipose tissue cross-sectional area was reduced by 31%.CONCLUSION Manipulation of caloric intake,fat percentage,and protein percentage may have influenced body composition after SCI.

From single to combinatorial therapies in spinal cord injuries for structural and functional restoration

Spinal cord injury results in paralysis, sensory disturbances, sphincter dysfunction, and multiple systemic secondary conditions, most arising from autonomic dysregulation. All this produces profound negative psychosocial implications for affected people, their families, and their communities;the financial costs can be challenging for their families and health institutions. Treatments aimed at restoring the spinal cord after spinal cord injury, which have been tested in animal models or clinical trials, generally seek to counteract one or more of the secondary mechanisms of injury to limit the extent of the initial damage. Most published works on structural/functional restoration in acute and chronic spinal cord injury stages use a single type of treatment: a drug or trophic factor, transplant of a cell type, and implantation of a biomaterial. Despite the significant benefits reported in animal models, when translating these successful therapeutic strategies to humans, the result in clinical trials has been considered of little relevance because the improvement, when present, is usually insufficient. Until now, most studies designed to promote neuroprotection or regeneration at different stages after spinal cord injury have used single treatments. Considering the occurrence of various secondary mechanisms of injury in the acute and sub-acute phases of spinal cord injury, it is reasonable to speculate that more than one therapeutic agent could be required to promote structural and functional restoration of the damaged spinal cord. Treatments that combine several therapeutic agents, targeting different mechanisms of injury, which, when used as a single therapy, have shown some benefits, allow us to assume that they will have synergistic beneficial effects. Thus, this narrative review article aims to summarize current trends in the use of strategies that combine therapeutic agents administered simultaneously or sequentially, seeking structural and functional restoration of the injured spinal cord.

Bromocriptine protects perilesional spinal cord neurons from lipotoxicity after spinal cord injury

Recent studies have revealed that lipid droplets accumulate in neurons after brain injury and evoke lipotoxicity,damaging the neurons.However,how lipids are metabolized by spinal cord neurons after spinal cord injury remains unclear.Herein,we investigated lipid metabolism by spinal cord neurons after spinal cord injury and identified lipid-lowering compounds to treat spinal cord injury.We found that lipid droplets accumulated in perilesional spinal cord neurons after spinal cord injury in mice.Lipid droplet accumulation could be induced by myelin debris in HT22 cells.Myelin debris degradation by phospholipase led to massive free fatty acid production,which increased lipid droplet synthesis,β-oxidation,and oxidative phosphorylation.Excessive oxidative phosphorylation increased reactive oxygen species generation,which led to increased lipid peroxidation and HT22 cell apoptosis.Bromocriptine was identified as a lipid-lowering compound that inhibited phosphorylation of cytosolic phospholipase A2 by reducing the phosphorylation of extracellular signal-regulated kinases 1/2 in the mitogen-activated protein kinase pathway,thereby inhibiting myelin debris degradation by cytosolic phospholipase A2 and alleviating lipid droplet accumulation in myelin debris-treated HT22 cells.Motor function,lipid droplet accumulation in spinal cord neurons and neuronal survival were all improved in bromocriptine-treated mice after spinal cord injury.The results suggest that bromocriptine can protect neurons from lipotoxic damage after spinal cord injury via the extracellular signal-regulated kinases 1/2-cytosolic phospholipase A2 pathway.

Visualizing Wallerian degeneration in the corticospinal tract after sensorimotor cortex ischemia in mice

Stroke can cause Wallerian degeneration in regions outside of the brain,particularly in the corticospinal tract.To investigate the fate of major glial cells and axons within affected areas of the corticospinal tract following stroke,we induced photochemical infarction of the sensorimotor cortex leading to Wallerian degeneration along the full extent of the corticospinal tract.We first used a routine,sensitive marker of axonal injury,amyloid precursor protein,to examine Wallerian degeneration of the corticospinal tract.An antibody to amyloid precursor protein mapped exclusively to proximal axonal segments within the ischemic cortex,with no positive signal in distal parts of the corticospinal tract,at all time points.To improve visualization of Wallerian degeneration,we next utilized an orthograde virus that expresses green fluorescent protein to label the corticospinal tract and then quantitatively evaluated green fluorescent protein-expressing axons.Using this approach,we found that axonal degeneration began on day 3 post-stroke and was almost complete by 7 days after stroke.In addition,microglia mobilized and activated early,from day 7 after stroke,but did not maintain a phagocytic state over time.Meanwhile,astrocytes showed relatively delayed mobilization and a moderate response to Wallerian degeneration.Moreover,no anterograde degeneration of spinal anterior horn cells was observed in response to Wallerian degeneration of the corticospinal tract.In conclusion,our data provide evidence for dynamic,pathogenic spatiotemporal changes in major cellular components of the corticospinal tract during Wallerian degeneration.

Pharmacological interventions targeting the microcirculation following traumatic spinal cord injury

Traumatic spinal cord injury is a devastating disorder chara cterized by sensory,motor,and autonomic dysfunction that seve rely compromises an individual's ability to perform activities of daily living.These adve rse outcomes are closely related to the complex mechanism of spinal cord injury,the limited regenerative capacity of central neurons,and the inhibitory environment fo rmed by traumatic injury.Disruption to the microcirculation is an important pathophysiological mechanism of spinal cord injury.A number of therapeutic agents have been shown to improve the injury environment,mitigate secondary damage,and/or promote regeneration and repair.Among them,the spinal cord microcirculation has become an important target for the treatment of spinal cord injury.Drug inte rventions targeting the microcirculation can improve the microenvironment and promote recovery following spinal cord injury.These drugs target the structure and function of the spinal cord microcirculation and are essential for maintaining the normal function of spinal neuro ns,axons,and glial cells.This review discusses the pathophysiological role of spinal cord microcirculation in spinal cord injury,including its structure and histopathological changes.Further,it summarizes the progress of drug therapies targeting the spinal cord mic rocirc ulation after spinal cord injury.

Progress in the generation of spinal cord organoids over the past decade and future perspectives

Spinal cord organoids are three-dimensional tissues derived from stem cells that recapitulate the primary morphological and functional characteristics of the spinal cord in vivo.As emerging bioengineering methods have led to the optimization of cell culture protocols,spinal cord organoids technology has made remarkable advancements in the past decade.Our literature search found that current spinal cord organoids do not only dynamically simulate neural tube formation but also exhibit diverse cytoarchitecture along the dorsal-ventral and rostral-caudal axes.Moreover,fused organoids that integrate motor neurons and other regionally specific organoids exhibit intricate neural circuits that allows for functional assessment.These qualities make spinal cord organoids valuable tools for disease modeling,drug screening,and tissue regeneration.By utilizing this emergent technology,researchers have made significant progress in investigating the pathogenesis and potential therapeutic targets of spinal cord diseases.However,at present,spinal cord organoid technology remains in its infancy and has not been widely applied in translational medicine.Establishment of the next generation of spinal cord organoids will depend on good manufacturing practice standards and needs to focus on diverse cell phenotypes and electrophysiological functionality evaluation.

In vivo imaging of the neuronal response to spinal cord injury:a narrative review

Deciphering the neuronal response to injury in the spinal cord is essential for exploring treatment strategies for spinal cord injury(SCI).However,this subject has been neglected in part because appropriate tools are lacking.Emerging in vivo imaging and labeling methods offer great potential for observing dynamic neural processes in the central nervous system in conditions of health and disease.This review first discusses in vivo imaging of the mouse spinal cord with a focus on the latest imaging techniques,and then analyzes the dynamic biological response of spinal cord sensory and motor neurons to SCI.We then summarize and compare the techniques behind these studies and clarify the advantages of in vivo imaging compared with traditional neuroscience examinations.Finally,we identify the challenges and possible solutions for spinal cord neuron imaging.

Passive activity enhances residual control ability in patients with complete spinal cord injury

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury level.However,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface electromyography.In this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord injury.Eleven patients with chronic complete thoracic spinal cord injury were recruited.Surface electromyography data from eight major leg muscles were acquired and compared before and after the passive activity protocol.The results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of activation.Although the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically significant.These findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

Primary thoracolumbar intraspinal malignant melanoma:A case report

BACKGROUND Primary intraspinal malignant melanoma is a very rare tumor that most often occurs in the cervical,thoracic,or thoracolumbar segment.CASE SUMMARY A rare case of primary thoracolumbar malignant melanoma is described.A 45-year-old female patient complained of low back pain with numbness and fatigue in both lower limbs.MR revealed an intradural space-occupying lesion at the thoracic 12 to lumbar 1 level.The tumor was partially excised,and a malignant melanoma was confirmed by histopathology.CONCLUSION Primary intraspinal malignant melanoma has rarely been reported,and surgical resection and related characteristics and diagnoses have been discussed.

Metastatic Spinal Tumors: Diagnostic Methods, Management and Prognosis at the Yaounde Central Hospital and Yaounde General Hospital

Introduction: Metastatic spinal tumors (MST) refer to secondary involvement of the vertebral column by hematogenously-disseminated metastatic cells. They could affect either the bony structures or the spinal cords. Mechanical instability and neurologic deficits resulting from spinal cord compression are the most common manifestations. Surgical intervention remains the most effective treatment for about 20% of patients who present with spinal cord compression. The prognosis is relatively poor. This work has as objectives to describe: the diagnostic tools, the different modalities of management and the prognostic elements of spine metastasis. Methodology: We conducted an ambispective cross-sectional descriptive study;with retrospective data collection from January 2015 to December 2021 and prospective collection from January to April 2022 in the “Neurosurgery” unit of the Yaounde Central Hospital and the “Oncology and Neurosurgery” units of Yaounde General Hospital. Result: We included 101 patients. The M/F sex ratio was 1.66. The average age of the participants was 56.44 years (±14.19 SD) with a median of 58 years. Metastatic spinal tumors were discovered in 61.39% of patients with a previously known primary tumor and 21.78% of patients had newly discovered tumors. The neurologic examination revealed a vertebral syndrome in 79.21% of cases, radicular syndrome in 60.40% and sub-lesional syndrome in 59.89%. Sensory disorders accounted for 39.60% and sphincter disorders accounted for 34.65%. According to the degree of severity, the lesions were classified as Frankel E (37.62%) followed by Frankel D (21.78%). Metastatic lesions were mostly found at the thoracic vertebrae (68.25%) and lumbar vertebrae (22.22%). The most represented primary tumors were: prostate tumors (41.58%) and breast tumors (23.76%);followed by malignant hemopathies (15.84%). Computed-tomography scan (CT-scan) was the most frequent diagnostic imaging technique used (71.28%). Analgesic treatment mostly involved level II analgesia (64.36%). High dose steroid therapy (greater than 80mg/24h) was used in more than half of the patients. Radiation therapy was performed in 24.75% of the patients, chemotherapy in 55.44% and specific surgical interventions performed in 20.79%. The most frequent surgical indication was complete motor deficit according to the Frankel classification (47.21%). One patient in four (23.76%) experienced improvement in functional prognosis with increased muscle strength after a period of 2 weeks to 5 months of treatment. About 1 in 10 patients (8.8%) rather had worsening of their neurologic status. We observed that there was a correlation between spine surgery and improvement in muscle strength (P-value less than 0.05). Patients (12) who had better recovery or preserved gait were those with partial compression (P-value = 0.0143). Four out of five patients (81.18%) of our series had an estimated survival of less than one year according to the Tokuhashi score. Conclusion: MSTs are frequent in our context. Most patients sought consultation late after the first symptoms appeared (principally back pain). The clinical examination revealed a high proportion of patients with spinal cord compression syndrome. Medical treatment was first-line for the management of pain and most patients who underwent surgical treatment had complete neurologic deficits. The functional prognosis was found to be improved by surgery and the vital prognosis depended on the Tokuhashi score, with better accuracy when the prediction is more than 12 months.

Mertk Reduces Blood-Spinal Cord Barrier Permeability Through the Rhoa/Rock1/P-MLC Pathway After Spinal Cord Injury

Disruption of the blood-spinal cord barrier(BSCB)is a critical event in the secondary injury following spinal cord injury(SCI).Mertk has been reported to play an important role in regulating inflammation and cytoskeletal dynamics.However,the specific involvement of Mertk in BSCB remains elusive.Here,we demonstrated a distinct role of Mertk in the repair of BSCB.Mertk expression is decreased in endothelial cells following SCI.Overexpression of Mertk upregulated tight junction proteins(TJs),reducing BSCB permeability and subsequently inhibiting inflammation and apoptosis.Ultimately,this led to enhanced neural regeneration and functional recovery.Further experiments revealed that the RhoA/Rock1/P-MLC pathway plays a key role in the effects of Mertk.These findings highlight the role of Mertk in promoting SCI recovery through its ability to mitigate BSCB permeability and may provide potential targets for SCI repair.

Enhancing m^(6)A modification in the motor cortex facilitates corticospinal tract remodeling after spinal cord injury

Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.

Clinical Outcome of Internal Fixation and Fusion in the Treatment of Spinal Fractures by Paraspinal Muscular Space Approach

Objective:To explore the clinical effect of internal fixation and fusion with the paraspinal muscle gap approach in the treatment of spinal fracture patients.Methods:104 spinal fracture patients admitted to Central Hospital of TCM from October 2022 to April 2024 were selected as the study subjects and were randomly divided into the control group(n=52)and the observation group(n=52)according to the random number table method.The control group was treated with the conventional approach of internal fixation surgery,and the observation group was treated with the paraspinal muscular interspace approach of internal fixation fusion.The two groups’general data,surgical indexes,pain,lumbar spine function,and postoperative complications were observed.Results:The baseline data of the two groups of patients were not statistically significant(all P>0.05)while the intraoperative bleeding,the first postoperative time getting up from bed,and the length of hospital stay of the patients in the observation group were shorter than that of the control group(all P=0.000<0.001),and the duration of the operation was longer than that of the control group(t=2.644,P=0.010<0.05);at 3 months postoperatively,the VAS scores of the patients in the observation group were significantly lower than those in the control group(t=10.768,P=0.000<0.001),and the JOA score was higher than that of the control group(t=6.498,P=0.000<0.001);the total complication rate of patients in the observation group(3/5.77%)was significantly lower than that of the control group(12/23.08%)(χ^(2)=6.310,P=0.012<0.05).Conclusion:In the treatment of spinal fracture patients,compared with the conventional approach to internal fixation surgery,the paraspinal muscular gap approach to internal fixation and fusion treatment is less traumatic,postoperative lumbar spine function recovery is faster,and can reduce the incidence of postoperative complications.

A single micro-LED manipulation system based on micro-gripper

Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techniques involved in the fabrication ofμLED-based devices is transfer printing.Although numerous methods have been proposed for transfer printing,improving the yield ofμLED arrays is still a formidable task.In this paper,we propose a novel method for improving the yield ofμLED arrays transferred by the stamping method,using an innovative design of piezoelectrically driven asymmetric micro-gripper.Traditional grippers are too large to manipulateμLEDs,and therefore two micro-sized cantilevers are added at the gripper tips.AμLED manipulation system is constructed based on the micro-gripper together with a three-dimensional positioning system.Experimental results using this system show that it can be used successfully to manipulateμLED arrays.

Resident immune responses to spinal cord injury:role of astrocytes and microglia

Spinal cord injury can be traumatic or non-traumatic in origin,with the latter rising in incidence and prevalence with the aging demographics of our society.Moreove r,as the global population ages,individuals with co-existent degenerative spinal pathology comprise a growing number of traumatic spinal cord injury cases,especially involving the cervical spinal cord.This makes recovery and treatment approaches particula rly challenging as age and comorbidities may limit regenerative capacity.For these reasons,it is critical to better understand the complex milieu of spinal cord injury lesion pathobiology and the ensuing inflammatory response.This review discusses microglia-specific purinergic and cytokine signaling pathways,as well as microglial modulation of synaptic stability and plasticity after injury.Further,we evaluate the role of astrocytes in neurotransmission and calcium signaling,as well as their border-forming response to neural lesions.Both the inflammatory and reparative roles of these cells have eluded our complete understanding and remain key therapeutic targets due to their extensive structural and functional roles in the nervous system.Recent advances have shed light on the roles of glia in neurotransmission and reparative injury responses that will change how interventions are directed.Understanding key processes and existing knowledge gaps will allow future research to effectively target these cells and harness their regenerative potential.

Epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China:a hospital-based retrospective study

Traumatic spinal cord injury is potentially catastrophic and can lead to permanent disability or even death.China has the largest population of patients with traumatic spinal cord injury.Previous studies of traumatic spinal cord injury in China have mostly been regional in scope;national-level studies have been rare.To the best of our knowledge,no national-level study of treatment status and economic burden has been performed.This retrospective study aimed to examine the epidemiological and clinical features,treatment status,and economic burden of traumatic spinal cord injury in China at the national level.We included 13,465 traumatic spinal cord injury patients who were injured between January 2013 and December 2018 and treated in 30 hospitals in 11 provinces/municipalities representing all geographical divisions of China.Patient epidemiological and clinical features,treatment status,and total and daily costs were recorded.Trends in the percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department and cost of care were assessed by annual percentage change using the Joinpoint Regression Program.The percentage of traumatic spinal cord injuries among all hospitalized patients and among patients hospitalized in the orthopedic department did not significantly change overall(annual percentage change,-0.5%and 2.1%,respectively).A total of 10,053(74.7%)patients underwent surgery.Only 2.8%of patients who underwent surgery did so within 24 hours of injury.A total of 2005(14.9%)patients were treated with high-dose(≥500 mg)methylprednisolone sodium succinate/methylprednisolone(MPSS/MP);615(4.6%)received it within 8 hours.The total cost for acute traumatic spinal cord injury decreased over the study period(-4.7%),while daily cost did not significantly change(1.0%increase).Our findings indicate that public health initiatives should aim at improving hospitals’ability to complete early surgery within 24 hours,which is associated with improved sensorimotor recovery,increasing the awareness rate of clinical guidelines related to high-dose MPSS/MP to reduce the use of the treatment with insufficient evidence.

Pre‑hatch thermal manipulation of embryos and post‑hatch baicalein supplementation mitigated heat stress in broiler chickens

Background High environmental temperatures induce heat stress in broiler chickens,affecting their health and pro-duction performance.Several dietary,managerial,and genetics strategies have been tested with some success in mitigating heat stress(HS)in broilers.Developing novel HS mitigation strategies for sustaining broiler production is critically needed.This study investigated the effects of pre-hatch thermal manipulation(TM)and post-hatch baica-lein supplementation on growth performance and health parameters in heat-stressed broilers.Results Six hundred fertile Cobb 500 eggs were incubated for 21 d.After candling on embryonic day(ED)10,238 eggs were thermally manipulated at 38.5℃ with 55%relative humidity(RH)from ED 12 to 18,then transferred to the hatcher(ED 19 to 21,standard temperature)and 236 eggs were incubated at a controlled temperature(37.5℃)till hatch.After hatch,180-day-old chicks from both groups were raised in 36 pens(n=10 birds/pen,6 replicates per treatment).The treatments were:1)Control,2)TM,3)control heat stress(CHS),4)thermal manipulation heat stress(TMHS),5)control heat stress supplement(CHSS),and 6)thermal manipulation heat stress supplement(TMHSS).All birds were raised under the standard environment for 21 d,followed by chronic heat stress from d 22 to 35(32–33℃ for 8 h)in the CHS,TMHS,CHSS,and TMHSS groups.A thermoneutral(22–24℃)environment was maintained in the Control and TM groups.RH was constant(50%±5%)throughout the trial.All the data were analyzed using one-way ANOVA in R and GraphPad software at P<0.05 and are presented as mean±SEM.Heat stress significantly decreased(P<0.05)the final body weight and ADG in CHS and TMHS groups compared to the other groups.Embryonic TM significantly increased(P<0.05)the expression of heat shock protein-related genes(HSP70,HSP90,and HSPH1)and antioxidant-related genes(GPX1 and TXN).TMHS birds showed a significant increment(P<0.05)in total cecal volatile fatty acid(VFA)concentration compared to the CHS birds.The cecal microbial analysis showed significant enrichment(P<0.05)in alpha and beta diversity and Coprococcus in the TMHSS group.Conclusions Pre-hatch TM and post-hatch baicalein supplementation in heat-stressed birds mitigate the detrimental effects of heat stress on chickens’growth performance,upregulate favorable gene expression,increase VFA produc-tion,and promote gut health by increasing beneficial microbial communities.