Effect of tibial cortex transverse transport in patients with recalcitrant diabetic foot ulcers: A prospective multicenter cohort study

Bone transport induces the release of factors with multi-tissue regenerative potential for diabetic wound healing in rats and patients

Tibial cortex transverse distraction is a surgical method for treating severe diabetic foot ulcers (DFUs), but the underlying mechanism is unclear. We show that antioxidant proteins and small extracellular vesicles (sEVs) with multiple-tissue regenerative potential are released during bone transport (BT) in humans and rats. These vesicles accumulate in diabetic wounds and are enriched with microRNAs (miRNAs) (e.g., miR-494-3p) that have high regenerative activities that improve the circulation of ischemic lower limbs while also promoting neovascularization, fibroblast migration, and nerve fiber regeneration. Deletion of miR-494-3p in rats reduces the beneficial effects of BT on diabetic wounds, while hydrogels containing miR-494-3p and reduced glutathione (GSH) effectively repair them. Importantly, the ginsenoside Rg1 can upregulate miR-494-3p, and a randomized controlled trial verifies that the regimen of oral Rg1 and GSH accelerates wound healing in refractory DFU patients. These findings identify potential functional factors for tissue regeneration and suggest a potential therapy for DFUs.

Impact of tibial transverse transport in tissue regeneration and wound healing with perspective on diabetic foot ulcers

In this editorial, we comment on an article by Liao et al published in the current issue of the World Journal of Diabetes. We focus on the clinical significance of tibial transverse transport (TTT) as an effective treatment for patients with diabetic foot ulcers (DFU). TTT has been associated with tissue regeneration, improved blood circulation, reduced amputation rates, and increased expression of early angiogenic factors. Mechanistically, TTT can influence macrophage polarization and growth factor upregulation. Despite this potential, the limitations and conflicting results of existing studies justify the need for further research into its optimal application and development. These clinical implications highlight the efficacy of TTT in recalcitrant DFU and provide lasting stimuli for tissue re-generation, and blood vessel and bone marrow improvement. Immunomodulation via systemic responses contributes to its therapeutic potential. Future studies should investigate the underlying molecular mechanisms to enhance our understanding and the efficacy of TTT. This manuscript emphasizes the potential of TTT in limb preservation and diabetic wound healing and suggests avenues for preventive measures against limb amputation in diabetes and peripheral artery disease. Here, we highlight the clinical significance of the TTT and its importance in healing DFU to promote the use of this technique in tissue regeneration.

Amide proton transfer weighted contrast has diagnostic capacity in detecting diabetic foot: an MRI-based case-control study

Objective

To evaluate the role of foot muscle amide proton transfer weighted (APTw) contrast and tissue rest perfusion in quantifying diabetic foot (DF) infection and its correlation with blood parameters.

Materials and methods

With approval from an ethical review board, this study included 40 diabetes mellitus (DM) patients with DF and 31 DM patients without DF or other lower extremity arterial disease. All subjects underwent MRI, which included foot sagittal APTw and coronal arterial spin labeling (ASL) imaging. The normalized MTRasym (3.5 ppm) and the ratio of blood flow (rBF) in rest status of the affected side lesions to the non-affected contralateral side were determined. The inter-group differences of these variables were evaluated. Furthermore, the association between normalized MTRasym (3.5 ppm), rBF, and blood parameters [fasting blood glucose (FBG), glycosylated hemoglobin content, C-reactive protein, neutrophil percentage, and white blood cell count] was explored. Using an ROC curve, the diagnostic capacity of normalized MTRasym (3.5 ppm), BF, and blood biochemical markers in differentiating with or without DF in DM was assessed.

Results

In the DF group, MTRasym (3.5 ppm) and BF in lesion and normalized MTRasym (3.5 ppm) were higher than those in the control group (p < 0.05). In addition, correlations were identified between normalized MTRasym (3.5 ppm) and blood parameters, such as C-reactive protein, glycosylated hemoglobin content, FBG, neutrophil ratio, and white blood cell (p < 0.001). Meanwhile, association between BF in lesion and blood parameters, such as C-reactive protein, neutrophil percentage, and FBG (p < 0.01). AUC of normalized MTRasym (3.5 ppm) in identifying with/without DF in patients with DM is 0.986 (95% CI, 0.918-1.00) with the sensitivity of 97.22% and the specificity of 100%.

Conclusion

Normalized MTRasym (3.5 ppm) and the BF in lesion may be treated as a safer and more convenient new indicator to evaluate the tissue infection without using a contrast agent, which may be useful in monitoring and preoperatively assessing DF patients with renal insufficiency.

Tibial cortex transverse transport promotes ischemic diabetic foot ulcer healing via enhanced angiogenesis and inflammation modulation in a novel rat model

BACKGROUND

Tibial Cortex Transverse Transport (TTT) represents an innovative surgical method for treating lower extremity diabetic foot ulcers (DFUs), yet its underlying mechanisms remain elusive. Establishing an animal model that closely mirrors clinical scenarios is both critical and novel for elucidating the mechanisms of TTT.

METHODS

We established a diabetic rat model with induced hindlimb ischemia to mimic the clinical manifestation of DFUs. TTT was applied using an external fixator for regulated bone movement. Treatment efficacy was evaluated through wound healing assessments, histological analyses, and immunohistochemical techniques to elucidate biological processes.

RESULTS

The TTT group demonstrated expedited wound healing, improved skin tissue regeneration, and diminished inflammation relative to controls. Marked neovascularization and upregulation of angiogenic factors were observed, with the HIF-1α/SDF-1/CXCR4 pathway and an increase in EPCs being pivotal in these processes. A transition toward anti-inflammatory M2 macrophages indicated TTT's immunomodulatory capacity.

CONCLUSION

Our innovative rat model effectively demonstrates the therapeutic potential of TTT in treating DFUs. We identified TTT's roles in promoting angiogenesis and modulating the immune system. This paves the way for further in-depth research and potential clinical applications to improve DFU management strategies.

Tibial cortex transverse transport regulates Orai1/STIM1-mediated NO release and improve the migration and proliferation of vessels via increasing osteopontin expression

Background

Diabetic foot is a major complication of diabetes. The bone transverse transport method could be applied in clinics for treatment, which could improve the metabolism of the tissues via lasting distraction forces. However, the process' specific regulating mechanism is still unknown.

Methods

Based on the notion that the healing of bones involves the recruitment of calcium ions, in this study, we established the model of tibial cortex transverse transport (TTT) on rats and then used tissue immunologic detection, such as the double fluorescent staining to explore the expression of the calcium channels' calcium release-activated calcium modulator 1 (Orai1)/stromal interaction molecule 1 (STIM1), which belong to the store-operated calcium entry (SOCE) signaling pathways on the tissues around the bone transport area. By using the laser capture microdissection (LCM) tool, we acquired samples of tissues around the bone and endeavored to identify pivotal protein molecules. Subsequently, we validated the functions of key protein molecules through in vitro and in vivo experiments.

Results

After protein profile analysis, we found the differentially expressed key protein osteopontin (OPN). The in vitro experiments verified that, being stimulated by OPN, the migration, proliferation, and angiogenesis of human umbilical vein endothelial cells (HUVEC) were observed to be enhanced. The activation of Orai1/STIM1 might increase the activity of endothelial nitric oxide synthase (eNOS) and its effect on releasing nitric oxide (NO). Subsequently, the migration and proliferation of the HUVECs are improved, which ultimately accelerates wound healing. These signaling pathway was also observed in the OPN-stimulated healing process of the skin wound surface of diabetic mice.

Conclusion

This study identifies the molecular biological mechanism of OPN-benefited the migration and proliferation of the HUVECs and provides ideas for searching for new therapeutic targets for drugs that repair diabetes-induced wounds to replace invasive treatment methods.

The translational potential of this article

The OPN is highly expressed in the tissues surrounding the TTT bone transfer area, which may possibly stimulate the activation of eNOS to increase NO release through the SOCE pathway mediated by Orai1/STIM1. This mechanism may play a significant role in the angiogenesis of diabetic foot's wounds promoted by TTT, providing new therapeutic strategies for the non-surgical treatment for this disease.

Modified tibial cortex transverse transport for diabetic foot ulcers with Wagner grade ≥ II: a study of 98 patients

Background

Diabetic foot ulcers constitute a substantial healthcare burden on a global scale and present challenges in achieving healing. Our objective was to assess the efficacy of modified tibial cortex transverse transport surgery in managing refractory diabetic foot ulcers.

Methods

We retrospectively analyzed clinical data from 98 patients suffering from diabetic foot ulcers classified as Wagner grade ≥II who were admitted to our medical facility between January 2020 and June 2022. All the patients were treated by modified tibial cortex transverse transport surgery, wherein the osteotomy scope was reduced to two rectangular bone windows measuring 1.5cm × 1.5cm each. Record the patient's general information and ulcer healing time; ulcer area, ankle-brachial index, WIFi classification, and visual analogue scale before and 3 months following the surgical intervention.

Results

The average duration of diabetes of 98 patients with diabetic foot ulcer was 20.22 ± 8.02 years, 52 patients had more than one toe gangrene on admission. The postoperative wound healing rate was 95.83% and the average healing time was 53.18 ± 20.18 days. The patients showed significant improvement in ankle-brachial index, WIFi classification, and visual analogue scale at 3 months postoperatively compared to preoperatively, with statistically significant differences (P< 0.05). Eight patients experienced complications, and the incidence of complications was 8.16%. Throughout the follow-up period, there were no instances of ulcer recurrence noted.

Conclusion

Modified tibial cortex transverse transport surgery demonstrates effectiveness in the management of diabetic foot ulcers by enhancing lower limb microcirculation and facilitating the process of wound healing.

A novel approach for diabetic foot diagnosis: Deep learning-based detection of lower extremity arterial stenosis

PURPOSE OF THE STUDY

Assessing the lower extremity arterial stenosis scores (LEASS) in patients with diabetic foot ulcer (DFU) is a challenging task that requires considerable time and efforts from physicians, and it may yield varying results. The presence of vascular wall calcification and other irrelevant tissue information surrounding the vessel can further compound the difficulties of this evaluation. Automatic detection of lower extremity arterial stenosis (LEAS) is expected to help doctors develop treatment plans for patients faster.

METHODS

In this paper, we first reconstructed the 3D model of blood vessels by medical digital image processing and then utilized it as the training data for deep learning (DL) in conjunction with the non-calcified part of blood vessels in the original data. We proposed an improved model of vascular stenosis small target detection based on YOLOv5. We added Convolutional Block Attention Module (CBAM) in backbone, replaced Path Aggregation Network (PANET) with Bidirectional Feature Pyramid Network (BiFPN) and replaced C3 with GhostC3 in neck to improve the recognition of three types of stenosis targets (I: <50 %, II: 51 % - 99 %, III: completely occluded). Additionally, we utilized K-Means++ instead of K-Means for better algorithm convergence performance, and enhanced the Complete-IoU (CIoU) loss function to Alpha-Scylla-IoU (ASIoU) loss for faster reasoning and convergence. Lastly, we conducted comparisons between our approach and five other prominent models.

RESULT

Our method had the best average ability to detect three types of stenosis with 85.40% mean Average Precision (mAP) and 74.60 Frames Per Second (FPS) and explored the possibility of applying DL to the detection of LEAS in diabetic foot. The code is available at github.com/wuchongxin/yolov5_LEAS.git.

Early hemodynamics after tibial transverse transport in patients with nonarterial stenosis and arterial stenosis diabetic foot

BACKGROUND

The diagnosis of peripheral arteriopathy in the diabetic foot is complicated by diabetes and its advanced complications. It has been found that diabetic foot can be categorized into arterial stenosis and non-arterial stenosis, both of which have significant differences in hemodynamic characteristics.

AIM

To evaluate the early hemodynamic changes in diabetic foot patients with nonarterial stenosis and arterial stenosis treated by tibial transverse transport (TTT) using high-frequency color Doppler ultrasonography (HFCDU) and a laser Doppler flowmeter.

METHODS

Twenty-five patients with Wagner grades 3-5 diabetic foot ulcers were treated with TTT, and the wound healing time and rate were recorded. Patients were grouped according to the results of preoperative lower-extremity ultrasonography. Cases with ≥ 50% stenosis in any of the femoral, popliteal, posterior tibial, anterior tibial, and peroneal arteries of the affected limb were classified as the arterial stenosis group (n = 16); otherwise, they were classified as the nonarterial stenosis group (n = 9). Before and one month after surgery, HFCDU was used to evaluate the degree of lower limb artery lesions and hemodynamic changes in patients. The degree of femoral-popliteal atherosclerotic stenosis, the degree of vascular stenosis and occlusion of the lower-knee outflow tract, and the degree of medial arterial calcification were scored; the three scores were added together to obtain the total score of lower extremity arteriopathy. PeriScanPIM3, a laser Doppler flowmeter system, was used to detect alterations in plantar microcirculation before and 1 mo after surgery. Wound healing and hemodynamic indices were compared between the two groups.

RESULTS

The wound healing time of the diabetic foot was significantly shorter in the nonarterial stenosis group than in the arterial stenosis group (47.8 ± 13 vs 85.8 ± 26, P < 0.05), and the wound healing rate of both groups was 100%. The preoperative total lower extremity arteriopathy scores were lower in the nonarterial stenosis group than those in the arterial stenosis group (18.89 ± 8.87 vs 24.63 ± 3.52, P < 0.05). The nonarterial stenosis group showed higher preoperative popliteal artery (POA) blood flow than the arterial stenosis group (204.89 ± 80.76 cc/min vs 76.75 ± 48.49 cc/min, P < 0.05). Compared with the baseline (before surgery), the postoperative POA blood flow of the affected limb in the nonarterial stenosis group decreased one month after surgery (134.11 ± 47.84 cc/min vs 204.89 ± 80.76 cc/min, P < 0.05), while that in the arterial stenosis group increased (98.44 ± 30.73 cc/min vs 61.69 ± 21.70 cc/min, P < 0.05). Although the POA blood flow in the arterial stenosis group was obviously improved one month after surgery, it was still lower than that in the nonarterial stenosis group (98.44 ± 30.73 cc/min vs 134.11 ± 47.84 cc/min, P < 0.05). The nonarterial stenosis group had higher preoperative plantar microcirculation than the arterial stenosis group (56.1 ± 9.2 vs 33.2 ± 7.5, P < 0.05); compared with the baseline, the plantar microcirculation in the arterial stenosis group was significantly improved one month after surgery (51.9 ± 7.2, P < 0.05), while that in the nonarterial stenosis group was reduced (35.9 ± 7.2, P < 0.05).

CONCLUSION

Based on preoperative HFCDU findings, diabetic foot patients can be divided into two categories: Those with nonarterial stenosis and those with arterial stenosis, with obvious differences in hemodynamic changes in the early postoperative period between them. In the early stage after TTT, the blood flow volume and velocity and the plantar microcirculation perfusion of the affected limb of the diabetic foot with nonarterial stenosis decreased compared with the baseline, while those of the diabetic foot with arterial stenosis improved significantly compared with the baseline, although both had smoothly healed diabetic foot ulcers.

[Effectiveness of tibial transverse transport combined with modified neurolysis in treatment of diabetic foot ulcers]

Objective

To investigate the effectiveness of tibial transverse transport (TTT) combined with modified neurolysis in treatment of diabetic foot ulcer (DFU) through a prospective randomized controlled study.

Methods

The patients with DFU and diabetic peripheral neuropathy, who were admitted between February 2020 and February 2022, were selected as the research objects, of which 31 cases met the selection criteria and were included in the study. The patients were divided into two groups by random number table method. The 15 patients in the trial group were treated with TTT combined with modified neurolysis, and the 16 patients in the control group received treatment with TTT alone. There was no significant difference in gender, age, duration of DFU, ulcer area, Wagner classification, as well as preoperative foot skin temperature, visual analogue scale (VAS) score, ankle-brachial index (ABI), motor nerve conduction velocity (MNCV) of the common peroneal nerve, MNCV of the tibial nerve, MNCV of the deep peroneal nerve, two-point discrimination (2-PD) of heel, and cross-sectional area (CSA) of the common peroneal nerve between the two groups ( P>0.05). The time for ulcer healing, foot skin temperature, VAS scores, ABI, 2-PD of heel, and CSA of the common peroneal nerve before operation and at 6 and 12 months after operation were recorded and compared between groups. The differences in MNCV of the common peroneal nerve, MNCV of the tibial nerve, and MNCV of the deep peroneal nerve between pre-operation and 12 months after operation were calculated.

Results

All patients in both groups were followed up 12-24 months (mean, 13.9 months). The surgical incisions in both groups healed by first intention and no needle tract infections occurred during the bone transport phase. Ulcer wounds in both groups healed successfully, and there was no significant difference in the healing time ( P>0.05). During the follow-up, there was no ulcer recurrences. At 12 months after operation, the MNCV of the common peroneal nerve, the MNCV of the tibial nerve, and the MNCV of the deep peroneal nerve in both groups accelerated when compared to preoperative values ( P<0.05). Furthermore, the trial group exhibited a greater acceleration in MNCV compared to the control group, and the difference was significant ( P<0.05). The foot skin temperature, VAS score, ABI, 2-PD of heel, and CSA of the common peroneal nerve at 6 and 12 months after operation significantly improved when compared with those before operation in both groups ( P<0.05). The 2-PD gradually improved over time, showing significant difference ( P<0.05). The 2-PD of heel and VAS score of the trial group were superior to the control group, and the differences were significant ( P<0.05). There was no significant difference in ABI, foot skin temperature, and CSA of the common peroneal nerve between groups after operation ( P>0.05).

Conclusion

Compared with TTT alone, the TTT combined with modified neurolysis for DFU can simultaneously solve both microcirculatory disorders and nerve compression, improve the quality of nerve function recovery, and enhance the patient's quality of life.

Learning curve of tibial cortex transverse transport: a cumulative sum analysis

OBJECTIVE

This study aimed to describe the learning curve of surgeons performing tibial cortex transverse transport (TTT) and explore its safety and effectiveness during the initial stages of surgeon's learning.

METHODS

The clinical data of patients with diabetic foot ulcers classified as Wagner grade ≥ 2, who underwent TTT at our hospital from January 2020 to July 2021, were included in this retrospective analysis. The same physician performed all procedures. Patients were numbered according to the chronological order of their surgery dates. The cumulative sum and piecewise linear regression were used to evaluate the surgeon's learning curve, identify the cut-off point, and divide the patients into learning and mastery groups. A minimum follow-up period of 3 months was ensured for all patients. Baseline data, perioperative parameters, complications, and efficacy evaluation indicators were recorded and compared between the two groups.

RESULTS

Sixty patients were included in this study based on the inclusion and exclusion criteria. After completing 20 TTT surgeries, the surgeon reached the cut-off point of the learning curve. Compared to the learning group, the mastery group demonstrated a significant reduction in the average duration of the surgical procedure (34.88 min vs. 54.20 min, P < 0.05) along with a notable decrease in intraoperative fluoroscopy (9.75 times vs. 16.9 times, P < 0.05) frequency, while no significant difference was found regarding intraoperative blood loss (P = 0.318). Of the patients, seven (11.7%) experienced complications, with three (15%) and four cases (10%) occurring during the learning phase and the mastery phase, respectively. The postoperative ulcer area was significantly reduced, and the overall healing rate was 94.8%. Significant improvements were observed in postoperative VAS, ABI, and WIFI classification (P < 0.05). There were no significant differences in the occurrence of complications or efficacy indicators between the learning and mastery groups (P > 0.05).

CONCLUSION

Surgeons can master TTT after completing approximately 20 procedures. TTT is easy, secure, and highly efficient for treating foot ulcers. Furthermore, TTT's application by surgeons can achieve almost consistent clinical outcomes in the initial implementation stages, comparable to the mastery phase.

Efficacy and safety of unilateral tibial cortex transverse transport on bilateral diabetic foot ulcers: A propensity score matching study

Background

Tibial Cortex Transverse Transport (TTT) has been demonstrated to be an effective treatment for unilateral diabetic foot ulcers (UDFUs). However, this retrospective study was designed to compare the efficacy and safety of unilateral TTT on bilateral diabetic foot ulcers (BDFUs).

Methods

This retrospective study included a review of patients with TTT treated from January 2017 to August 2019, Propensity Score Matching (PSM) was performed to compare patients with BDFUs to those with UDFUs. Ulcer healing, recurrence, and major amputation rates were evaluated at 1-year follow-up. Changes in foot vessels were assessed in the BDFUs group using computed tomography angiography (CTA).

Results

A total of 140 patients with DFUs (106 UDFUs and 34 BDFUs) were included in the study. UDFUs and BDFUs were matched in a 1:1 ratio (34 in each group) using PSM. No significant difference was observed at 1-year-follow-up [91.2% (31/34) vs. 76.5% (26/34), OR 0.315 (95% CI 0.08 to 1.31), P ​= ​0.10] and 6-month-follow-up [70.6% (24/34) vs. 50.0% (17/34), OR 0.85 (95% CI 0.15 to 1.13), P ​= ​0.08] in two groups. Significant differences in rates of major amputation and recurrence between the groups (P ​> ​0.05) were not observed. The BDFUs group appeared more angiogenesis of the foot by CTA after 8 weeks of operation.

Conclusion

Results of this study suggest that severe BDFUs can be effectively treated by unilateral TTT. TTT is easy to operate and effective, which may be a good alternative for treating severe BDFUs.

The translational potential of this article

In previous retrospective clinical studies, TTT has demonstrated promising clinical outcomes in the management of diabetic foot ulcers. In this current study, we aim to investigate the potential use of TTT in treating distant tissue defects by evaluating the limited availability and safety of TTT for the management of bilateral diabetic foot. While additional basic and clinical research is necessary to fully elucidate the underlying mechanisms, our study offers insight into the potential therapeutic use of TTT for this condition.