OBJECTIVE: To investigate of effectiveness of free fascia lata flap assisted by indocyanine green angiography (ICGA) in treatment of Myerson type Ⅱ and Ⅲ chronic Achilles tendon ruptures. METHODS: A clinical data of 14 patients with Myerson type Ⅱ and Ⅲ chronic Achilles tendon ruptures between March 2020 and June 2024 was retrospectively analyzed. All Achilles tendon defects were repaired with the free fascia lata assisted by ICGA during operation. There were 12 males and 2 females with an average age of 45.4 years (range, 26-71 years). The causes of Achilles tendon rupture included sports injury in 10 cases, Achilles tendon-related tendinopathy in 3 cases, and glass laceration injury in 1 case. The time from Achilles tendon rupture to operation was 4-40 weeks (median, 4.5 weeks). Preoperative MRI examination showed that the defect length of the Achilles tendon was 2-5 cm (mean, 3.2 cm). The operation time and intraoperative blood loss were recorded. The color Doppler ultrasound (CDU) and MRI were taken to observe the foot blood vessels and the tendon healing. The visual analogue scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) score, Achilles Tendon rupture score (ATRS), and range of motion of the ankle joint were used to estimate the pain and function of ankle joint. RESULTS: All operations of the 14 patients were successfully completed. The operation time ranged from 3.00 to 4.50 hours (mean, 3.60 hours). The intraoperative blood loss ranged from 10 to 50 mL (mean, 36.4 mL). After operation, 1 patient had exudation at the recipient site, which healed after dressing change; the other incisions healed by first intention. All incisions at the donor sites healed by first intention. All patients were followed up 6-36 months (mean, 11.4 months). The CDU of the foot at 1 month after operation showed that the blood flow signal of the perforating vessels of the fascia lata flap was clear. The ankle MRI at 2 months after operation showed the good continuity of the Achilles tendon. No complication such as the Achilles tendon re-rupture, ankle stiffness, or scar contracture occurred during follow-up. Compared with preoperative score, the AOFAS score, ATRS score, and plantar flexion range of motion significantly increased at 1, 3, and 6 months after operation ( P<0.05), while the VAS score and dorsiflexion range of motion significantly decreased ( P<0.05). The AOFAS score, ATRS score, and VAS score at 3 and 6 months further improved when compared with those at 1 month ( P<0.05); however, there was no significant difference in the range of motion of the ankle joint ( P>0.05). There was no significant difference in above indicators between 3 and 6 months after operation ( P>0.05). CONCLUSION The treatment of Myerson type Ⅱ and Ⅲ chronic Achilles tendon ruptures with free fascia lata flaps under the guidance of ICGA has the advantages of precise design, fast healing, and a wide range of adaptability.
Humans ; Achilles Tendon/diagnostic imaging* ; Male ; Female ; Adult ; Middle Aged ; Retrospective Studies ; Indocyanine Green ; Rupture/surgery* ; Aged ; Fascia Lata/transplantation* ; Angiography/methods* ; Free Tissue Flaps/blood supply* ; Plastic Surgery Procedures/methods* ; Tendon Injuries/diagnostic imaging* ; Treatment Outcome ; Chronic Disease

OBJECITVE: To investigate the effectiveness of three-dimensional (3D) printing-assisted vascularized fibular graft for repairing metatarsal defects. METHODS: Between November 2021 and February 2024, 11 patients with varying degrees of metatarsal defects caused by trauma were treated. There were 10 males and 1 female, aged 22-67 years, with a mean age of 51.2 years. The defect locations were as follows: the first metatarsal in 4 cases, the fifth metatarsal in 2 cases, the first and the second metatarsals in 1 case, the first to third metatarsals in 1 case, the third and the fourth metatarsals in 1 case, the third to fifth metatarsals in 1 case, and the first to fifth metatarsals in 1 case. The preoperative American Orthopaedic Foot & Ankle Society (AOFAS) score was 67.0 (48.5, 72.5). Based on 3D-printed bilateral feet models and mirrored healthy-side foot arch angles for preoperative planning and design, the vascularized fibular graft was performed to repair the metatarsal defects. At last follow-up, the medial and lateral longitudinal arches of bilateral feet were measured on weight-bearing X-ray films, and functional assessment was conducted using the AOFAS score. RESULTS: All operations were successfully completed, with an operation time ranging from 180 to 465 minutes (mean, 246.8 minutes). All incisions healed by first intention, with no occurrence of osteomyelitis. All patients were followed up 6-22 months (mean, 10 months). X-ray film reviews showed bone graft healing in all cases, with a healing time of 3-6 months (mean, 5 months). All patients underwent internal fixator removal at 6-12 months after operation. At last follow-up, no significant difference was observed in the medial and lateral longitudinal arches between the healthy and affected feet ( P>0.05). The AOFAS score of the affected foot was 78.0 (73.5, 84.0), showing a significant improvement compared to the preoperative score ( P<0.05). The effectiveness was rated as excellent in 1 case, good in 7 cases, fair in 2 cases, and poor in 1 case. Linear scarring remained at the donor site, with no functional impairment in adjacent joint movement. CONCLUSION 3D printing-assisted vascularized fibular graft for repairing metatarsal defects can effectively restore the physiological angle of the foot arch, facilitate the recovery of weight-bearing alignment, promote good bone healing, and yield satisfactory clinical outcomes.
Humans ; Printing, Three-Dimensional ; Middle Aged ; Male ; Fibula/blood supply* ; Female ; Metatarsal Bones/injuries* ; Adult ; Bone Transplantation/methods* ; Aged ; Plastic Surgery Procedures/methods* ; Young Adult ; Treatment Outcome

Alzheimer's disease (AD) is characterized by cognitive and functional deterioration, with pathological features such as amyloid-beta (Aβ) aggregates in the extracellular spaces of parenchymal neurons and intracellular neurofibrillary tangles formed by the hyperphosphorylation of tau protein. Despite a thorough investigation, current treatments targeting the reduction of Aβ production, promotion of its clearance, and inhibition of tau protein phosphorylation and aggregation have not met clinical expectations, posing a substantial obstacle in the development of drugs for AD. Recently, artificial intelligence (AI), computational biology (CB), and systems biology (SB) have emerged as promising methodologies in AD research. Their capacity to analyze extensive and varied datasets facilitates the identification of intricate patterns, thereby enriching our comprehension of AD pathology. This paper provides a comprehensive examination of the utilization of AI, CB, and SB in the diagnosis of AD, including the use of imaging omics for early detection, drug discovery methods such as lecanemab, and complementary therapies like phototherapy. This review offers novel perspectives and potential avenues for further research in the realm of translational AD studies.

Severe open tibiofibular fractures account for approximately 28.1% of all open fractures. Among them, Gustilo-Anderson type IIIB/C fractures present significant clinical challenges due to associated bone and soft tissue defects, high infection rates, and risk of amputation. Inadequate preoperative assessment may lead to suboptimal emergency surgical planning or intraoperative complications. Historically, external fixation was often preferred, but this approach has been associated with limitations such as restricted joint mobility, delayed bone union, joint stiffness, and disuse osteoporosis, resulting in poor functional recovery. With advancements of debridement techniques, standardization of antibiotic use, and popularization of early soft tissue coverage, early internal fixation has gained broader acceptance. Nevertheless, controversies persist regarding the choice of fixation method, timing of definitive fixation, use of reamed versus unreamed intramedullary nailing, and necessity of fibular fixation. To standardize the diagnosis and early management of severe open tibiofibular fractures, reduce complication rates, and improve functional recovery, the Society of Microsurgery of the Chinese Medical Association organized a panel of domestic experts to develop the Evidence-based guideline for the diagnosis and early fixation of severe open tibiofibular fractures ( version 2025), using evidence-based methodology. The guidelines provided 12 recommendations covering diagnostic and early fixation strategies of severe open tibiofibular fractures, aiming to provide clinicians with scientifically grounded and standardized guidance.

Osteosarcoma is a highly aggressive bone tumor that primarily affects children and adolescents. It is characterized by high rates of recurrence and metastasis, with the tumor microenvironment playing a pivotal role in disease progression. Exosomes, small extracellular vesicles secreted by various cell types, exert dual roles in osteosarcoma. On one hand, exosomes derived from osteosarcoma cells remodel the microenvironment to facilitate tumor progression. For instance, they carry miR-501-3p to activate the PTEN/PI3K/Akt signaling pathway, promoting osteoclastogenesis and bone destruction; TGF-β1/3 stimulates bone marrow-derived mesenchymal stem cells (BMSCs) to secrete IL-6 and IL-8, enhancing the inflammatory microenvironment; and miR-25-3p suppresses DKK3, thereby promoting angiogenesis and invasion. Moreover, exosomes contribute to the formation of a pre-metastatic niche by transporting miR-21 and miR-675, which promote lung metastasis, activate cancer-associated fibroblasts, and enhance invasiveness via the linc00881/miR-29c-3p/MMP2 axis. Conversely, exosomes derived from mesenchymal stem cells deliver tumor-suppressive miRNAs such as miR-1913, miR-150, and miR-206, which target NRSN2, IGF2BP1, and TRA2B, thereby inhibiting tumor growth. In the context of drug resistance, osteosarcoma-derived exosomes transport MDR-1 mRNA and circRNA_103801, contributing to chemotherapy resistance. Additionally, TGF-β-induced IL-6 activates the STAT3 pathway, further enhancing resistance. In terms of immune modulation, these exosomes suppress T cell and NK cell activity and upregulate PDL1 expression, promoting immune evasion. Exosomes also hold therapeutic potential. They can serve as drug delivery vehicles, for example, carrying doxorubicin or kanamycin, to achieve targeted cytotoxicity via ferroptosis or apoptosis. Engineered exosomes enriched with miR-101 or MEG3 have been shown to inhibit metastasis, while plant-derived exosome-like nanoparticles activate the P38/JNK pathway to induce apoptosis. These approaches aim to improve therapeutic efficacy while minimizing adverse effects. In summary, exosomes play multifaceted roles in the pathogenesis of osteosarcoma and offer promising avenues for early diagnosis, prognostic assessment, and precision therapy, including pathway-targeted strategies. However, challenges remain in optimizing exosome isolation, standardizing large-scale production, and validating clinical applications. Addressing these issues is essential for translating laboratory findings into effective clinical treatments.

Objective:To investigate the clinical effect of reconstruction of the degloving injury of thumb and finger with free perforator flap of superficial peroneal artery.Methods:This is a retrospective study. From June 2020 to June 2023, 18 superficial peroneal artery perforator flaps from 14 calves were used to treat 15 degloved digital wounds of 14 patients in the Department of Hand Surgery, Suzhou Ruihua Orthopaedic Hospital. There were 13 single digital degloving wounds and 1 two-digital degloving wounds. Of which, 3 digits were reconstructed with 2 free perforator flaps of ipsilateral superficial peroneal artery and 12 with a single free perforator flap of superficial peroneal artery. The size of wounds was 4.0 cm×2.0 cm-10.0 cm×4.0 cm, and the flaps were 5.0 cm×3.0 cm-12.0 cm×4.0 cm in size. The donor sites in calves were sutured layer by layer with absorptive sutures. Postoperative follow-ups were conducted through regular outpatient visits, phone calls or WeChat. Survival of flaps, postoperative complications, therapeutic effect of the flaps and patient satisfaction were observed.Results:There was no vascular compromise or wound infection of the flaps. All patients were included in the 4 to 36 months of postoperative follow-up, with an average of 9.86 months. All flaps had good appearance, without obvious swelling. Colour and texture of the flaps was close to the surrounding skin. The flaps had no obvious pigmentation or ulcer and scar hyperplasia at recipient site. Sensation of the flaps recovered to S 2 to S 3. There was no obvious scar hyperplasia, pain or dysfunction at donor sites. According to the comprehensive evaluation scale of flap, the scores were found at 81 to 91, with an average score of 85 in the 14 patients, and of whom 2 were excellent and 12 were good. Patient satisfaction was evaluated according to the Michigan Hand Outcomes Questionnaire (MHQ) and 10 patients were very satisfied and 4 were satisfied. Conclusion:Free perforator flap of superficial peroneal artery is one of the ideal flaps in reconstruction of degloving injury of thumb and fingers. It features constant and multiple perforators, reliable blood supply, high survival rate, flexible in design, thin and a small damage to the donor site.

Objective:To investigate the clinical efficacy of combination of a Flow-through anterolateral thigh myocutaneous flap with a contralateral great saphenous vein grafting in reconstruction of Gustilo ⅢC foot and ankle injury in emergency surgery.Methods:This retrospective study analysed the clinical data of 9 patients who were admitted in the Department of Wound Repair Surgery, Suzhou Ruihua Orthopaedic Hospital between September 2021 and October 2023. All patients were diagnosed with Gustilo ⅢC foot and ankle injury and met the predefined inclusion criteria. The average age of the patients was 45 (26-64) years. The mean of Mangled Extremity Severity Score (MESS) was 8.2 points, with a range from 5 to 10 points. The wound area after debridement ranged from 15.5 cm×6.0 cm to 24.5 cm×12.5 cm, with the vascular occlusion or defect at 4.0-20.0 (mean, 6.3) cm in length. The size of the flap was 16.5 cm×7.0 cm-25.5 cm×13.5 cm. During surgery, segments of the great saphenous vein were excised in the length of 5.0-21.0 cm, at an approximately 6.5 cm in length. The Flow-through anterolateral thigh myocutaneous flap was employed to reconstruct the soft tissue defect and to establish vascular connections between the anterior or posterior tibial arteries and veins, with the vessels carried by the flap. Additionally, the contralateral great saphenous vein was taken to bridge the posterior or anterior tibial arteries and veins. Follow-ups were carried out by outpatient visits, telephone calls and WeChat interviews. The flap viability, limb blood circulation, wound healing at both donor and recipient sites, as well as functional recovery of the affected limbs was observed. Sensation recovery of the flap was assessed according to the rating standard established by the British Medical Research Council (BMRC) , while the function recovery of foot and ankle was evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) scale.Results:All flaps successfully survived without vascular complication. Eight affected limbs were effectively cured, while a calf that had an infection and necrosis of a long segment of tibia and fibula was amputated below-the-knee in the stage-II surgery. One of the donor sites of flap was covered with a medium-thickness skin graft from lower abdomen due to the large size of the flap, while the other donor sites were directly sutured and healed at first intention. One patient developed postoperative bone infection, which was successfully treated through re-debridement and antibiotic bone cement filling. Another patient experienced partial necrosis at the distal hallux due to a prolonged limb ischemia, and a stump repair surgery was performed. All patients were entered into the postoperative follow-up for 15.3 (6-24) months. At the final follow-up visit, satisfactory colour and texture were observed on all flaps, although minor oedema was present. Donor sites healed well and the donor limb function was not affected. Sensory evaluation rated S 2 in 5 flaps and S 3 in 3 flaps according to BMRC. Functional assessment of foot and ankle of the affected limb yielded excellent in 2 patients, good in 5 patients and fair in 1 patient according to AOFAS. Conclusion:Flow-through anterolateral thigh myocutaneous flap combined with a contralateral great saphenous vein grafting enables one-stage reconstruction for soft tissue defect and blood circulation of the affected limb. It is a good method in the treatment of Gustilo ⅢC foot and ankle injury in emergency surgery.

Objective:To investigate and compare the clinical effect of anterolateral thigh perforator flap (ALTPF) with a pedicle of the oblique branch and a pedicle of the descending branch of lateral circumflex femoral artery in treatment of wounds in limbs.Methods:From December 2020 to December 2021, a retrospective analysis was performed on 53 patients who received reconstruction of wound with free ALTPF. Patients were divided into a group of ALTPF with oblique branch of lateral circumflex femoral artery (oblique branch group) and a group of ALTPF with descending branch of lateral circumflex femoral artery (descending branch group) according to the vascular pedicle. Of the blique branch group ( n=28): 12 patients had the wound in wrist, 3 in forearm, 7 in ankle and foot, and 6 in calf. The time for ALTPF reconstructive surgery after admission ranged from 0 to 25 days, with an average of 15.3 days. Among the patients, 6 received emergency treatment. The size of soft tissue defect was 5.0 cm×8.0 cm-21.0 cm×10.0 cm, and the size of flap was 6.0 cm×8.5 cm-22.0 cm×10.0 cm. Of the descending branch group ( n=25): 7 patients had the wound in wrist, 3 in forearm, 2 in upper arm, 10 in ankle and foot, and 3 in calf. The time for ALTPF reconstructive surgery after admission ranged from 0 to 22 days, with an average of 14.7 days. Among the patients, 4 received emergency treatment. The size of soft tissue defect was 12.0 cm×4.0 cm-28.0 cm×10.0 cm, and the size of flap was 13.0 cm×5.0 cm-28.0 cm×10.0 cm. The donor sites were directly sutured in layers after the surgery. The number of perforating branches in anterolateral thigh was detected by high-frequency CDU and recorded before surgery. The number, calibre, type of perforating branches observed during surgery and the size of flaps, length of the vascular pedicles of the flaps and the time for flap harvesting were recorded. Postoperative follow-up was conducted through outpatient visits, WeChat and other means. The survival of the flap, the healing of the donor site and complications were observed. The outcomes of flap reconstructive surgery were evaluated by the comprehensive score scale during follow-up. The data were analyzed using SPSS 22.0 statistical software. P<0.05 was considered statistically significant. Results:There is no significant difference in general information between the 2 groups ( P>0.05). In the oblique branch group, the length of vascular pedicle of the flaps was 5.0-15.0 (9.89±2.66) cm, the ratio of intermuscular perforator was 56.52%(26/46), and the inner diameter of perforators was 0.3-1.1 (0.67±0.20) mm and the time for flap harvesting was 22.5 (6.0-75.0) minutes. In the descending branch group, the length of vascular pedicle of the flaps was 7.0-16.0 (11.52±2.67) cm, the proportion of intermuscular perforator was 34.69%(17/49), the inner diameter of perforators of the flap was 0.3-1.2(0.70±0.23) mm and the time for flap harvesting was 35.0 (9.0-78.0) minutes. In comparison with the 2 groups, it was found that the oblique branch group had a shorter length of vascular pedicle, a higher proportion of intermuscular perforating branches and a shorter time in flap harvesting. The difference was statistically significant ( P<0.05). No statistically significant was found in the number and inner diameter of the perforating branches between the 2 groups ( P>0.05). Altogether, 51 flaps in the 2 groups survived. One flap in each group had partial necrosis at the distal end of flap, with the necrotic sizes of 5.0 cm×5.0 cm and 5.0 cm×4.0 cm, respectively, and they healed after skin grafting without obvious vascular. The survival rates of the 2 groups of flaps were 96.43% and 96.00%, respectively. The postoperative follow-up lasted for 6-18 months, with an average of 12 months. The appearance of the flaps in 10 patients was slightly bloated, and flap thinning and plastic surgery were carried out at 4-6 months after the primary flap surgery. Else, all the flaps regained protective sensation, all the donor sites and recipient sites healed well, and the donor sites of the thigh was good without pain, numbness or other discomfort. Comprehensive evaluations of the flaps were conducted at the final follow-up with the comprehensive evaluation scale for flaps. The scores of 28 patients in the oblique branch group achieved 73-98 with an average of 86.3. Twelve patients had the scores in comprehensive evaluation of excellent, 14 of good, and 2 of fair, with the excellent and good rate of 92.86%(26/28). The scores of 25 patients in the descending branch group ranged from 72-97 with an average of 85.8, of which 11 patients had the scores of comprehensive evaluation in excellent, 12 in good and 2 in fair, with the excellent and good rate of 92.00% (23/25). There was no statistically significant difference in the survival rate and comprehensive evaluation scales between the 2 groups of flaps ( P>0.05). Conclusion:ALTPF pedicled with oblique branch of lateral circumflex femoral artery has a higher number of perforating branch, a shorter harvesting time and less damage to the donor site than those of the ALTPF pedicled with descending branch of lateral circumflex femoral artery. When both oblique and descending branches of lateral circumflex femoral artery are present or with the absence of a descending perforating branch, the oblique branch of lateral circumflex femoral artery is the preferred perforating vessel for pedicle in harvesting of an ALTPF.

Objective:To explore the clinical effects of free bilateral turbocharged anterolateral thigh flaps in tandem in repairing extensive wounds in the foot and ankle.Methods:The study was a retrospective observational study. From April 2020 to June 2023, 12 patients with extensive wounds in the foot and ankle who met the inclusion criteria were admitted to the Department of Wound Repair Surgery of Suzhou Ruihua Orthopedic Hospital, including 8 males and 4 females, aged 21 to 65 years. The wound area after debridement ranged from 27 cm×14 cm to 37 cm×20 cm. The bilateral perforator flaps pedicled with either oblique or descending branches of the lateral circumflex femoral artery were designed and harvested based on the size and shape of the wounds. The individual flap incision area ranged from 16 cm×9 cm to 34 cm×12 cm. The non-homologous perforator of the flap on the one side was turbocharged by anastomosing it with the gross muscular branch or main vessel of the oblique or descending branch of the lateral circumflex femoral artery from the flap. Subsequently, the proximal end of the oblique or descending branch of the lateral circumflex femoral artery and its accompanying vein from the flap on the one side were connected end-to-end with either the anterior tibial artery and vein, posterior tibial artery and vein, or dorsal foot artery and vein in the recipient area, the distal end of the oblique or descending branch of the lateral circumflex femoral artery and its accompanying vein from the flap on the one side were anastomosed end-to-end with a source vessel originating from flap on the other side. The wounds in the flap donor areas were sutured directly. The number and source of perforators carried by the flaps and the duration of the flap repair surgery were recorded. The survival of the flap, the occurrence of vascular crisis, and the wound healing at both donor and recipient areas were observed after surgery. The flap condition, appearance and function of the affected limb were observed during follow-up. At the last follow-up, the sensory function of the flap was assessed using the British Medical Research Council's sensory rating standard, the foot and ankle function of the affected limb was evaluated according to the American Orthopedic Foot and Ankle Society scoring standard.Results:A total 24 flaps were successfully harvested, carrying 60 perforators, including 34 perforators from the oblique branch of the lateral circumflex femoral artery, 24 perforators from the descending branch of the lateral circumflex femoral artery, one perforator from the transverse branch of the lateral circumflex femoral artery, and one perforator from the direct branch of the femoral artery. The duration of the flap repair surgery ranged from 4.2 to 9.0 hours. The flaps of 12 patients exhibited complete survival after surgery. A total of two flaps of two patients experienced venous crisis after surgery but survived through emergency exploration. One patient encountered undesirable wound healing at the donor area of flap on the one side after surgery, which healed after dressing change, debridement, and suturing. The remaining patients' donor area wounds healed. Two patients displayed impaired wound healing in the recipient area, which improved after dressing change and resection of residual sequestrum, and the wounds in the recipient area of other patients healed successfully. During the follow-up of 4-26 months, the flaps demonstrated favorable color and texture, slight edematous appearance, and partial sensory recovery, as well as good aesthetic and functional restoration of the affected limbs. At the last follow-up, the sensory function of the flap was assessed as grade S2 in 9 cases and grade S3 in 3 cases; the foot and ankle function of the affected limb was evaluated as excellent in two cases, good in 9 cases, and fair in one case.Conclusions:The bilateral turbocharged anterolateral thigh flaps have numerous sources of perforators. By implementing supercharging of non-homologous perforators within the flap, the vascular supply to the flap is turbocharged, thereby mitigating the risk of extensive flap necrosis. The flap is an effective approach for repairing extensive wounds in the foot and ankle, resulting in improved function of the affected limb after repair.

Osteosarcoma is a highly aggressive bone tumor that primarily affects children and adolescents. It is characterized by high rates of recurrence and metastasis, with the tumor microenvironment playing a pivotal role in disease progression. Exosomes, small extracellular vesicles secreted by various cell types, exert dual roles in osteosarcoma. On one hand, exosomes derived from osteosarcoma cells remodel the microenvironment to facilitate tumor progression. For instance, they carry miR-501-3p to activate the PTEN/PI3K/Akt signaling pathway, promoting osteoclastogenesis and bone destruction; TGF-β1/3 stimulates bone marrow-derived mesenchymal stem cells (BMSCs) to secrete IL-6 and IL-8, enhancing the inflammatory microenvironment; and miR-25-3p suppresses DKK3, thereby promoting angiogenesis and invasion. Moreover, exosomes contribute to the formation of a pre-metastatic niche by transporting miR-21 and miR-675, which promote lung metastasis, activate cancer-associated fibroblasts, and enhance invasiveness via the linc00881/miR-29c-3p/MMP2 axis. Conversely, exosomes derived from mesenchymal stem cells deliver tumor-suppressive miRNAs such as miR-1913, miR-150, and miR-206, which target NRSN2, IGF2BP1, and TRA2B, thereby inhibiting tumor growth. In the context of drug resistance, osteosarcoma-derived exosomes transport MDR-1 mRNA and circRNA_103801, contributing to chemotherapy resistance. Additionally, TGF-β-induced IL-6 activates the STAT3 pathway, further enhancing resistance. In terms of immune modulation, these exosomes suppress T cell and NK cell activity and upregulate PDL1 expression, promoting immune evasion. Exosomes also hold therapeutic potential. They can serve as drug delivery vehicles, for example, carrying doxorubicin or kanamycin, to achieve targeted cytotoxicity via ferroptosis or apoptosis. Engineered exosomes enriched with miR-101 or MEG3 have been shown to inhibit metastasis, while plant-derived exosome-like nanoparticles activate the P38/JNK pathway to induce apoptosis. These approaches aim to improve therapeutic efficacy while minimizing adverse effects. In summary, exosomes play multifaceted roles in the pathogenesis of osteosarcoma and offer promising avenues for early diagnosis, prognostic assessment, and precision therapy, including pathway-targeted strategies. However, challenges remain in optimizing exosome isolation, standardizing large-scale production, and validating clinical applications. Addressing these issues is essential for translating laboratory findings into effective clinical treatments.