With the rapid development of competitive sports, the incidence of anterior cruciate ligament (ACL) injury is on the rise. Such injuries may shorten athletes′ career and lead to other long-term adverse consequences. Although athletes generally recover well after ACL reconstruction, many still struggle to return to their pre-injury performance levels. Advances in the understanding of ACL anatomy and injury mechanisms, along with the evolution of surgical techniques and rehabilitation methods, have provided more individualized and tailored options for athletes following ACL injuries. However, there is currently no consensus in China regarding surgical and rehabilitation strategies for competitive athletes aiming to return to sports after ACL injuries. To this end, the Sports Medicine Committee of the Chinese Research Hospital Association and the Editorial Board of the Chinese Journal of Trauma jointly formulated the Expert consensus on surgical treatment and rehabilitation for competitive sports athletes returning to sports after anterior cruciate ligament injury ( version 2025), and presented 14 recommendations covering surgical indications, preoperative rehabilitation, surgical timing, surgical strategies and postoperative rehabilitation strategies, aiming to improve the surgical treatment and rehabilitation system for ACL injuries in competitive athletes and facilitate their return to high-level sports performance after injury.

Objective:To investigate the clinical effectiveness of autologous hamstring tendon reconstruction with preserved synovial sheath combined with remnant suture in the treatment of anterior cruciate ligament (ACL) tears.Methods:A retrospective study was conducted to analyze the clinical data of 38 patients with ACL tear who had been admitted to Department of Sports Medicine, The Fourth Hospital of Wuhan from January 2016 to July 2020. There were 30 males and 8 females, with an age of (25.4±7.2) years. By the typing of MRI Sherman tear locations (MSTL) for anterior cruciate ligament, 7 cases were Type I and 31 cases type II. A total of 18 patients underwent single bundle reconstruction of autologous hamstring tendon combined with remnant suture (group A), and the other 20 patients underwent conventional reconstruction to clean the synovial sheath of ACL (group B). The operation time,Tenger scores, Lysholm scores, International Knee Documentation Committee (IKDC) subjective score and side-to-side differences in relaxation at pre- operation, 1 year and 2 years after operation, as well as ACL healing of the affected knee at 2 years after operation, were observed and compared between the 2 groups. The graft synovial coverage was evaluated by secondary arthroscopy in some cases.Results:There was no significant difference in the preoperative general data between the 2 groups, indicating comparability ( P>0.05). All patients were followed up for (38.5±8.4) months. No surgical site infection or knee stiffness occurred in the 2 groups after operation, and 2 patients in each group developed intermuscular venous thrombosis at a lower limb. There was no significant difference in operation time between the 2 groups ( P>0.05). There were significant differences in Tenger score [(6.3±1.6) points versus (4.7±1.7) points], Lysholm score [(93.4±4.2) points versus (85.9±4.3) points] and IKDC subjective score [(89.1±2.9) points versus (81.2±2.9) points] between group A and group B at 1 year after operation ( P<0.05), but there was no significant difference in Tenger score, Lysholm score or IKDC subjective score between the 2 groups at 2 years after operation ( P>0.05). There was no significant difference in side-to-side difference in relaxation between the 2 groups at 1 year or 2 years after operation ( P>0.05). MRI evaluation at 2 years after operation showed no recurrent rupture or no sign of impingement between the graft and the intercondylar fossa in either group. Conventional secondary arthroscopy for 2 patients in group A and 3 patients in group B revealed better synovial coverage in group A. Conclusion:In the treatment of ACL tears of MSTL types I and II, compared with conventional reconstruction to clean the synovial sheath of ACL, autologous hamstring tendon reconstruction with preserved synovial sheath combined with remnant suture can lead to better functional recovery at 1 year after operation, though there is no significant difference in function at 2 years after operation.

BACKGROUND:Chronic rotator cuff injury is often companied by tendon degeneration and impaired function of tendon-derived stem cells.As am important cytokine,platelet-derived growth factor-DD has a regulatory effect on the proliferation and differentiation of tendon-derived stem cells.OBJECTIVE:To investigate the effect of platelet-derived growth factor-DD on the proliferation and multilineage differentiation of tendon-derived stem cells in human chronic rotator cuff injury.METHODS:Tendon-derived stem cells were isolated from human chronic rotator cuff injury tissue and cultured in vitro.Immunofluorescence staining was used to observe the cytoskeletal morphology of tendon-derived stem cells.Flow cytometry was used to identify the phenotype of tendon-derived stem cells.Tendon-derived stem cells were divided into two groups.The control group did not receive any intervention.The platelet-derived growth factor-DD group was treated with 5 μg/mL platelet-derived growth factor-DD.The effect of platelet-derived growth factor-DD on the proliferation and multilineage differentiation of tendon-derived stem cells was evaluated by cell proliferation assay and three-lineage differentiation assay.RESULTS AND CONCLUSION:(1)The number of EdU-positive cells in the platelet-derived growth factor-DD group was significantly increased compared with the control group(P＜0.05).Tendon-derived stem cells entered the rapid proliferation phase earlier,and the cell growth was logarithmic.(2)The positive areas of Oil Red O staining,Alcian Blue staining,and Alizarin Red staining in the platelet-derived growth factor-DD group were significantly larger than those in the control group(P＜0.05).(3)The above results show that platelet-derived growth factor-DD significantly promotes the proliferation and adipogenic,osteogenic,and chondrogenic differentiation of tendon-derived stem cells.

Objective The biomechanical performance of Ilizarov fixator models with different configurations for humeral shaft defect was compared,so as to provide a biomechanical basis for selecting the appropriate circular external fixation structure for the clinical treatment of humeral shaft defects using Ilizarov technology.Methods Based on CT data of the humerus from a healthy volunteer,the external fixators with three configurations,namely,hybrid frame,semi-ring frame and 90° fan frame were established.The finite element method was used to simulate the displacement and stress distribution under different loading conditions,and the finite element results were validated by biomechanical tests.Results Finite element analysis results:in terms of displacement,under compression,tensile and torque conditions,the displacement of 90° fan model was smaller than that of hybrid and semi-ring models.In terms of stress,the 90° fan model had the smallest displacement under tensile condition.In compression and torque tests,the semi-annular model had the lowest stress.Biomechanical test results:the semi-ring model exhibited the smallest displacement under axial compression,but there was no significant difference between the three models(P＞0.05).Conclusions The semi-ring and 90° fan frames can achieve a similar stability as the traditional hybrid frame through the strategy of'reducing the ring and increasing the stem'.The unilateral structure of the 90° fan frame has the advantages of small size,light weight,and structural stability,as well as a small impact on the shoulder and elbow joints,which makes it more valuable in clinical applications.

Objective The biomechanical performance of Ilizarov fixator models with different configurations for humeral shaft defect was compared,so as to provide a biomechanical basis for selecting the appropriate circular external fixation structure for the clinical treatment of humeral shaft defects using Ilizarov technology.Methods Based on CT data of the humerus from a healthy volunteer,the external fixators with three configurations,namely,hybrid frame,semi-ring frame and 90° fan frame were established.The finite element method was used to simulate the displacement and stress distribution under different loading conditions,and the finite element results were validated by biomechanical tests.Results Finite element analysis results:in terms of displacement,under compression,tensile and torque conditions,the displacement of 90° fan model was smaller than that of hybrid and semi-ring models.In terms of stress,the 90° fan model had the smallest displacement under tensile condition.In compression and torque tests,the semi-annular model had the lowest stress.Biomechanical test results:the semi-ring model exhibited the smallest displacement under axial compression,but there was no significant difference between the three models(P＞0.05).Conclusions The semi-ring and 90° fan frames can achieve a similar stability as the traditional hybrid frame through the strategy of'reducing the ring and increasing the stem'.The unilateral structure of the 90° fan frame has the advantages of small size,light weight,and structural stability,as well as a small impact on the shoulder and elbow joints,which makes it more valuable in clinical applications.

BACKGROUND:Chronic rotator cuff injury is often companied by tendon degeneration and impaired function of tendon-derived stem cells.As am important cytokine,platelet-derived growth factor-DD has a regulatory effect on the proliferation and differentiation of tendon-derived stem cells.OBJECTIVE:To investigate the effect of platelet-derived growth factor-DD on the proliferation and multilineage differentiation of tendon-derived stem cells in human chronic rotator cuff injury.METHODS:Tendon-derived stem cells were isolated from human chronic rotator cuff injury tissue and cultured in vitro.Immunofluorescence staining was used to observe the cytoskeletal morphology of tendon-derived stem cells.Flow cytometry was used to identify the phenotype of tendon-derived stem cells.Tendon-derived stem cells were divided into two groups.The control group did not receive any intervention.The platelet-derived growth factor-DD group was treated with 5 μg/mL platelet-derived growth factor-DD.The effect of platelet-derived growth factor-DD on the proliferation and multilineage differentiation of tendon-derived stem cells was evaluated by cell proliferation assay and three-lineage differentiation assay.RESULTS AND CONCLUSION:(1)The number of EdU-positive cells in the platelet-derived growth factor-DD group was significantly increased compared with the control group(P＜0.05).Tendon-derived stem cells entered the rapid proliferation phase earlier,and the cell growth was logarithmic.(2)The positive areas of Oil Red O staining,Alcian Blue staining,and Alizarin Red staining in the platelet-derived growth factor-DD group were significantly larger than those in the control group(P＜0.05).(3)The above results show that platelet-derived growth factor-DD significantly promotes the proliferation and adipogenic,osteogenic,and chondrogenic differentiation of tendon-derived stem cells.

With the rapid development of competitive sports, the incidence of anterior cruciate ligament (ACL) injury is on the rise. Such injuries may shorten athletes′ career and lead to other long-term adverse consequences. Although athletes generally recover well after ACL reconstruction, many still struggle to return to their pre-injury performance levels. Advances in the understanding of ACL anatomy and injury mechanisms, along with the evolution of surgical techniques and rehabilitation methods, have provided more individualized and tailored options for athletes following ACL injuries. However, there is currently no consensus in China regarding surgical and rehabilitation strategies for competitive athletes aiming to return to sports after ACL injuries. To this end, the Sports Medicine Committee of the Chinese Research Hospital Association and the Editorial Board of the Chinese Journal of Trauma jointly formulated the Expert consensus on surgical treatment and rehabilitation for competitive sports athletes returning to sports after anterior cruciate ligament injury ( version 2025), and presented 14 recommendations covering surgical indications, preoperative rehabilitation, surgical timing, surgical strategies and postoperative rehabilitation strategies, aiming to improve the surgical treatment and rehabilitation system for ACL injuries in competitive athletes and facilitate their return to high-level sports performance after injury.

Objective:To investigate the clinical effectiveness of autologous hamstring tendon reconstruction with preserved synovial sheath combined with remnant suture in the treatment of anterior cruciate ligament (ACL) tears.Methods:A retrospective study was conducted to analyze the clinical data of 38 patients with ACL tear who had been admitted to Department of Sports Medicine, The Fourth Hospital of Wuhan from January 2016 to July 2020. There were 30 males and 8 females, with an age of (25.4±7.2) years. By the typing of MRI Sherman tear locations (MSTL) for anterior cruciate ligament, 7 cases were Type I and 31 cases type II. A total of 18 patients underwent single bundle reconstruction of autologous hamstring tendon combined with remnant suture (group A), and the other 20 patients underwent conventional reconstruction to clean the synovial sheath of ACL (group B). The operation time,Tenger scores, Lysholm scores, International Knee Documentation Committee (IKDC) subjective score and side-to-side differences in relaxation at pre- operation, 1 year and 2 years after operation, as well as ACL healing of the affected knee at 2 years after operation, were observed and compared between the 2 groups. The graft synovial coverage was evaluated by secondary arthroscopy in some cases.Results:There was no significant difference in the preoperative general data between the 2 groups, indicating comparability ( P>0.05). All patients were followed up for (38.5±8.4) months. No surgical site infection or knee stiffness occurred in the 2 groups after operation, and 2 patients in each group developed intermuscular venous thrombosis at a lower limb. There was no significant difference in operation time between the 2 groups ( P>0.05). There were significant differences in Tenger score [(6.3±1.6) points versus (4.7±1.7) points], Lysholm score [(93.4±4.2) points versus (85.9±4.3) points] and IKDC subjective score [(89.1±2.9) points versus (81.2±2.9) points] between group A and group B at 1 year after operation ( P<0.05), but there was no significant difference in Tenger score, Lysholm score or IKDC subjective score between the 2 groups at 2 years after operation ( P>0.05). There was no significant difference in side-to-side difference in relaxation between the 2 groups at 1 year or 2 years after operation ( P>0.05). MRI evaluation at 2 years after operation showed no recurrent rupture or no sign of impingement between the graft and the intercondylar fossa in either group. Conventional secondary arthroscopy for 2 patients in group A and 3 patients in group B revealed better synovial coverage in group A. Conclusion:In the treatment of ACL tears of MSTL types I and II, compared with conventional reconstruction to clean the synovial sheath of ACL, autologous hamstring tendon reconstruction with preserved synovial sheath combined with remnant suture can lead to better functional recovery at 1 year after operation, though there is no significant difference in function at 2 years after operation.

OBJECTIVE: To explore the effect of chitosan (CS) hydrogel loaded with tendon-derived stem cells (TDSCs; hereinafter referred to as TDSCs/CS hydrogel) on tendon-to-bone healing after rotator cuff repair in rabbits. METHODS: TDSCs were isolated from the rotator cuff tissue of 3 adult New Zealand white rabbits by Henderson step-by-step enzymatic digestion method and identified by multidirectional differentiation and flow cytometry. The 3rd generation TDSCs were encapsulated in CS to construct TDSCs/CS hydrogel. The cell counting kit 8 (CCK-8) assay was used to detect the proliferation of TDSCs in the hydrogel after 1-5 days of culture in vitro, and cell compatibility of TDSCs/CS hydrogel was evaluated by using TDSCs alone as control. Another 36 adult New Zealand white rabbits were randomly divided into 3 groups ( n=12): rotator cuff repair group (control group), rotator cuff repair+CS hydrogel injection group (CS group), and rotator cuff repair+TDSCs/CS hydrogel injection group (TDSCs/CS group). After establishing the rotator cuff repair models, the corresponding hydrogel was injected into the tendon-to-bone interface in the CS group and TDSCs/CS group, and no other treatment was performed in the control group. The general condition of the animals was observed after operation. At 4 and 8 weeks, real-time quantitative PCR (qPCR) was used to detect the relative expressions of tendon forming related genes (tenomodulin, scleraxis), chondrogenesis related genes (aggrecan, sex determining region Y-related high mobility group-box gene 9), and osteogenesis related genes (alkaline phosphatase, Runt-related transcription factor 2) at the tendon-to-bone interface. At 8 weeks, HE and Masson staining were used to observe the histological changes, and the biomechanical test was used to evaluate the ultimate load and the failure site of the repaired rotator cuff to evaluate the tendon-to-bone healing and biomechanical properties. RESULTS: CCK-8 assay showed that the CS hydrogel could promote the proliferation of TDSCs ( P<0.05). qPCR results showed that the expressions of tendon-to-bone interface related genes were significantly higher in the TDSCs/CS group than in the CS group and control group at 4 and 8 weeks after operation ( P<0.05). Moreover, the expressions of tendon-to-bone interface related genes at 8 weeks after operation were significantly higher than those at 4 weeks after operation in the TDSCs/CS group ( P<0.05). Histological staining showed the clear cartilage tissue and dense and orderly collagen formation at the tendon-to-bone interface in the TDSCs/CS group. The results of semi-quantitative analysis showed that compared with the control group, the number of cells, the proportion of collagen fiber orientation, and the histological score in the TDSCs/CS group increased, the vascularity decreased, showing significant differences ( P<0.05); compared with the CS group, the proportion of collagen fiber orientation and the histological score in the TDSCs/CS group significantly increased ( P<0.05), while there was no significant difference in the number of cells and vascularity ( P>0.05). All samples in biomechanical testing failed at the repair site during the testing process. The ultimate load of the TDSCs/CS group was significantly higher than that of the control group ( P<0.05), but there was no significant difference compared to the CS group ( P>0.05). CONCLUSION TDSCs/CS hydrogel can induce cartilage regeneration to promote rotator cuff tendon-to-bone healing.
Rabbits ; Animals ; Rotator Cuff/surgery* ; Chitosan ; Hydrogels ; Rotator Cuff Injuries/surgery* ; Wound Healing ; Tendons/surgery* ; Collagen ; Stem Cells ; Biomechanical Phenomena

Objective:To investigate the early clinical effect of fascia lata autograft bridging combined with the long head of biceps tendon transposition for treatment of irreparable massive rotator cuff tear.Methods:All of 31 cases of massive irreparable rotator cuff tear treated in our hospital from March 2016 to March 2020 were analyzed retrospectively. Among them, 17 cases (10 males, 7 females) were repaired with fascia lata autograft bridging under arthroscopy (patch group), the average age was 61.47±6.63 (ranging from 51 to 72) and 14 cases (4 males, 10 females) were repaired with fascia lata autograft bridging combined with the long head of biceps tendon transposition (combined group), the average age was 62.57±6.11 (ranging from 53 to 71). The operation time, intraoperative blood loss, postoperative complications, visual analogue scale (VAS) of pain before operation, at 1 week and 12 months after operation, Constant-Murley score of shoulder joint and American Association of shoulder and elbow Surgeons (ASES) score before operation, at 6 months and 12 months after operation were compared between the two groups. The outcome of rotator cuff healing was evaluated by MRI 1 year after operation.Results:All patients were followed up for 12-27 months (mean 18.33 ±6.8 months). There was no perioperative complication, and there was no significant difference in operation time between the two groups ( P>0.05) . The VAS score in the patch group was significantly higher than the combined group 1 week after operation ( t=2.09, P=0.048) , and there was no significant difference in VAS score 12 months after operation between the two groups. Constant-Murley score and ASES score in the combined group were significantly higher than the patch group at 6 months after operation ( t=5.23, P<0.001; t=4.45, P<0.001) , and there was no significant difference in Constant score and ASES score between the two groups at 12 months after operation. Constant score and ASES score in the two groups were significantly higher than those before operation. One year after operation, the MRI of the affected shoulder showed that the incidence of autograft patch thinning (Sugaya grade III) was 52.94%, the autograft patch structure failure rate (Sugaya grade IV and V) was 17.65% in the patch group, the autograft patch thinning rate (Sugaya grade III) was 35.71%, and the structural failure rate (Sugaya grade IV and V) was 7.14% in the combined group. The difference was statistically significant (χ 2=7.12, P=0.028) . Conclusion:Fascia lata autograft patch bridging combined with long head of biceps tendon transposition technique for treatment of irreparable massive rotator cuff tear has less pain 1 week after operation and better recovery of shoulder function half a year after operation. MRI showed better patch healing 1 year after operation.