Tibial periosteal distraction as an adjunct to percutaneous transluminal angioplasty for diabetic foot ulcers complicated by peripheral arterial disease/chronic limb-threatening ischemia: a retrospective cohort study

Abstract

Background

Diabetic foot ulcer (DFU) complicated by peripheral arterial disease/chronic limb-threatening ischemia (PAD/CLTI) is a major cause of impaired wound healing and limb loss. In some patients, local tissue perfusion remains insufficient and wound healing is delayed even after technically successful percutaneous transluminal angioplasty (PTA). Tibial periosteal distraction (TPD) may offer incremental benefit after PTA, but direct comparative evidence supporting its role as an adjunctive strategy remains limited.

Methods

This single-center retrospective cohort study included patients with DFU and PAD/CLTI who underwent index PTA. In the adjunctive group, TPD was performed as a prespecified staged procedure within 7 days after PTA during the same hospitalization. The primary outcome was time to complete wound healing, and the key secondary outcome was 12-month amputation-free survival (AFS). Secondary outcomes included complete wound healing at 3 and 6 months, wound recurrence within 12 months, and longitudinal changes in wound area, transcutaneous oxygen pressure (TcPO₂), and ankle-brachial index (ABI).

Results

A total of 64 patients were included, with 24 in the PTA + TPD group and 40 in the PTA-alone group. PTA + TPD was associated with a shorter time to complete wound healing than PTA alone, and this association remained significant after adjustment for prespecified baseline covariates (adjusted HR, 3.90; 95% CI 2.23–6.83; P < 0.001). The 3-month complete wound healing rate was also higher in the PTA + TPD group (P = 0.016), whereas the 6-month healing rate did not differ significantly between groups (P = 0.642). Although 12-month AFS was numerically higher in the PTA + TPD group (95.8% vs 82.5%), the between-group difference was not statistically significant (P = 0.240). Linear mixed-effects models showed more favorable trajectories of wound area, TcPO₂, and ABI in the PTA + TPD group, with significant group-by-time interactions for all three outcomes (all P < 0.001). Complication rates were comparable between groups (all P > 0.05).

Conclusion

In patients with DFU and PAD/CLTI, the addition of TPD after PTA was associated with faster wound healing and more favorable perfusion-related changes during follow-up. TPD may have potential value as a post-revascularization adjunct, although this requires confirmation in prospective studies.

Introduction

Diabetic foot ulcer (DFU) is one of the most serious chronic complications of diabetes and is strongly associated with infection progression, persistent non-healing wounds, amputation, and increased mortality [1]. Even after apparent wound closure, DFU remains highly prone to recurrence and often follows a chronic, relapsing course, thereby imposing a sustained burden through functional impairment, hospital readmission, and long-term healthcare use [2]. The development and progression of DFU are multifactorial, involving peripheral neuropathy, lower-extremity ischemia, and abnormal foot biomechanics. Among these contributors, the coexistence of peripheral arterial disease/chronic limb-threatening ischemia (PAD/CLTI) is associated with particularly poor outcomes [3]. Persistent hypoperfusion, inadequate local oxygen delivery, and impaired tissue repair capacity interact to increase the risk of delayed healing, infection progression, and limb salvage failure in this population [4, 5]. Therefore, in the comprehensive management of DFU, restoration and maintenance of tissue perfusion sufficient to support wound repair remain central to improving healing and reducing the risk of amputation [3, 6].

For patients with DFU complicated by PAD/CLTI, revascularization remains the cornerstone of treatment for restoring the healing potential of ischemic wounds [7]. As a principal endovascular approach, percutaneous transluminal angioplasty (PTA) can re-establish arterial inflow and provide the perfusion required for wound repair [7–9]. However, technical success in reopening the target vessel does not necessarily ensure adequate perfusion at the wound level. In some patients, local perfusion remains suboptimal, and wound healing is still delayed after PTA, suggesting that restoration of macrocirculatory flow alone may not fully reverse local ischemia-related impairment of tissue repair [10, 11]. More recent evidence indicates that, in patients with CLTI, wound outcomes may depend less on vessel patency per se than on the establishment of effective in-line flow to the affected angiosome or wound-related region [12]. Accordingly, strategies that further enhance tissue-level perfusion after revascularization may still provide incremental clinical value [13].

Tibial periosteal distraction (TPD) has recently emerged as a novel perfusion-enhancing technique for ischemic lower-extremity wounds [14]. In contrast to tibial transverse transport (TTT), which typically requires corticotomy and external fixation, TPD avoids complete cortical osteotomy and may promote angiogenesis and improve local perfusion through gradual subperiosteal distraction [15, 16]. Early clinical studies have suggested that TPD may improve perfusion-related parameters, including transcutaneous oxygen pressure (TcPO₂) and local skin temperature, while also promoting wound healing [17]. However, the current literature has largely examined TPD as a relatively independent limb-salvage technique [14] or compared it with TTT and conventional care [16]. Whether TPD provides additional benefit after revascularization remains insufficiently studied. Against this background, the present study compared PTA combined with TPD versus PTA alone in patients with DFU and PAD/CLTI to evaluate the effectiveness and safety of TPD as an adjunctive strategy after revascularization.

Methods

Study design and ethical considerations

This single-center retrospective cohort study was conducted at a tertiary hospital in accordance with the Declaration of Helsinki. The study protocol was approved by the Institutional Review Board of the Affiliated Mindong Hospital of Fujian Medical University (IRB No. K2026031901). The requirement for informed consent was waived because of the retrospective design and the use of anonymized data. The study was designed and reported in accordance with the STROBE guidelines [18]. Eligible patients were identified through the hospital electronic medical record system.

Participants

Inclusion criteria were as follows: (1) age ≥ 18 years; (2) a diagnosis of DFU based on the 2023 update of the International Working Group on the Diabetic Foot (IWGDF) definition of diabetes-related foot ulcer, with the presence of a persistent foot wound [19]; (3) limb threat classified as Wound, Ischemia, and foot Infection (WIfI) clinical stage 2–4 according to the Society for Vascular Surgery classification system [20]; (4) preoperative computed tomography angiography (CTA) or digital subtraction angiography (DSA) demonstrating lower-extremity arterial stenosis or occlusion, mainly involving the anterior tibial, posterior tibial, or peroneal arteries, consistent with PAD/CLTI.

Exclusion criteria were: (1) non-diabetic foot ulcers; (2) acute arterial embolism or acute limb ischemia; (3) local soft-tissue or skin conditions of the ipsilateral lower leg that were unsuitable for TPD; (4) severe systemic infection, diabetic ketoacidosis, end-stage major organ failure, or any other condition precluding surgery; (5) missing key imaging, outcome, or follow-up data.

Study cohort and grouping

Between September 2022 and January 2025, 71 patients with DFU and PAD/CLTI who underwent lower-extremity PTA were screened. After exclusions, 64 patients were included in the final analysis. PTA served as the index revascularization procedure in all patients. In the adjunctive group, TPD was scheduled as a prespecified staged procedure and completed within 7 days after PTA during the same hospitalization. Assignment to the PTA + TPD group or the PTA-alone group was determined at index admission by a multidisciplinary team based on local wound conditions, patient acceptance, and device availability, rather than being introduced later in response to delayed healing during follow-up. The final cohort consisted of 24 patients in the PTA + TPD group and 40 in the PTA-alone group. A STROBE flow diagram of patient selection and cohort allocation is shown in Fig. 1.

Fig. 1.

STROBE flow diagram of patient selection and cohort allocation

Treatment procedures

PTA procedure

All patients underwent percutaneous transluminal angioplasty as the index revascularization procedure. Target-vessel selection was individualized according to wound location, lesion morphology, technical feasibility, and distal runoff as assessed on preprocedural imaging and intraprocedural angiography. When feasible, the wound-related artery was preferentially targeted. If direct wound-related revascularization was not achievable, the procedural goal was to establish at least one uninterrupted straight-line flow to the foot through the vessel considered most suitable for durable technical success and distal perfusion. Balloon angioplasty was used as the primary treatment, with stent placement or other endovascular procedures performed when indicated. Technical success was assessed on completion angiography and was defined as satisfactory recanalization of the target lesion, restoration of antegrade flow, and the absence of evident flow-limiting residual stenosis, dissection, or thrombosis.

TPD procedure

In patients assigned to adjunctive TPD, the procedure was performed during the index hospitalization within 7 days after successful PTA. The key operative steps are shown in Fig. 2. With the patient in the supine position, an approximately 1 cm skin incision was made on the medial aspect of the tibia, approximately 4 cm distal to the tibial plateau, between the tibial crest and the posterior border of the tibia. After exposure of the periosteum, an approximately 1 cm transverse incision was made perpendicular to its long axis, followed by blunt subperiosteal dissection in the proximal and distal directions. A locking distraction fixation system, including a locking distraction plate, cannulated locking screws, and Kirschner wires (Zhejiang Canwell Medical Co., Ltd., Jinhua, China), was inserted beneath the periosteum. Cannulated locking screws were placed through the plate holes, and Kirschner wires were then inserted through the screws to secure the construct. The wound was then closed in layers and covered with a sterile dressing.

Fig. 2.

Key steps of tibial periosteal distraction. (A) Medial tibial skin incision. (B) Exposure of the periosteum. (C) Blunt subperiosteal dissection in the proximal and distal directions. (D) Subperiosteal insertion of the locking distraction plate. (E) Placement of cannulated locking screws and Kirschner wires to secure the construct, followed by layered wound closure. (F) Intraoperative anteroposterior radiograph confirming implant position

Postoperative management and wound care

After PTA, both groups received the same standardized wound care and limb-salvage management, including debridement when necessary, infection control, glycemic management, appropriate antiplatelet, anticoagulant, or vasoactive therapy, and management of cardiovascular risk factors. Local wound care was tailored to wound status and included standard dressings, negative-pressure wound therapy, or antibiotic-loaded bone cement coverage when indicated. Limited drainage, minor amputation, or local soft-tissue procedures were performed when clinically required. The two groups were managed according to the same principles with respect to wound assessment, dressing changes, and other aspects of perioperative care.

In the PTA + TPD group, TPD was incorporated into a planned in-hospital treatment pathway after PTA rather than being used as a salvage procedure for delayed healing during follow-up. Following device implantation, gradual distraction was initiated after a short latency period. The standard distraction rate was 1.0 mm/day, divided into three sessions daily, with a total distraction distance of approximately 10–12 mm over 10–14 days. In cases of marked pain or excessive local skin tension, the rate was reduced to 0.5 mm/day or distraction was temporarily suspended.

Outcome measures

For both groups, outcome analyses were anchored to the date of index PTA as time zero. The primary outcome was time to complete wound healing, defined as the interval from PTA to complete epithelialization of all active wounds maintained for at least 2 weeks without exudate. In patients with multiple wounds, healing of the last remaining wound was used as the event time. The key secondary outcome was 12-month amputation-free survival (AFS). Other secondary outcomes included complete wound healing rates at 3 and 6 months, 12-month wound recurrence, longitudinal changes in wound area at 1, 3, and 6 months after PTA, and dynamic changes in TcPO₂ and ankle-brachial index (ABI) from baseline to 1, 3, and 6 months. Safety outcomes included pin-tract infection, device displacement or failure, deep infection, local skin necrosis, and other treatment-related adverse events.

Statistical analysis

Analyses were performed using IBM SPSS Statistics (version 26.0; IBM Corp., Armonk, NY, USA) and Python (statsmodels). Continuous variables are presented as mean ± standard deviation or median (interquartile range), as appropriate, and categorical variables as counts (percentages). Between-group baseline comparisons were performed using the independent-samples t test, Mann–Whitney U test, χ² test, or Fisher’s exact test, as appropriate. Missing data were handled using complete-case analysis.

TPD was implemented as a prespecified staged adjunctive procedure within 7 days after PTA during the same hospitalization. Because no patient experienced complete wound healing, major amputation, or death before TPD, the date of index PTA was used as time zero for both groups. Time to complete wound healing was analyzed using Kaplan–Meier estimates and the log-rank test. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox proportional hazards models. In addition to the crude model, a multivariable model was fitted with prespecified clinically relevant covariates, including WIfI stage, baseline wound area, and infection status. Complete wound healing rates at 3 and 6 months, 12-month amputation-free survival (AFS), wound recurrence within 12 months, and other categorical outcomes were compared using the χ² test or Fisher’s exact test, as appropriate. Longitudinal changes in wound area, TcPO₂, and ABI were analyzed using linear mixed-effects models, with group, time, and the group-by-time interaction included as fixed effects and patient included as a random effect. All tests were two-sided, and P < 0.05 was considered statistically significant.

Results

Baseline characteristics

Baseline characteristics are summarized in Table 1. No statistically significant between-group differences were observed in age, sex, smoking history, HbA1c, renal dysfunction, BMI, baseline wound area, infection status, WIfI stage, preoperative ABI, TcPO₂, or prior ipsilateral revascularization history (all P > 0.05). Overall, the two groups were generally similar with respect to demographic features, metabolic status, wound severity, and ischemia-related indicators.

Table 1.

Baseline characteristics of the study population

Characteristic	PTA + TPD (n = 24)	PTA-alone (n = 40)	P value
Age, years	67.71 ± 10.01	71.80 ± 9.65	0.115a
Male sex, n (%)	19 (79.2%)	21 (52.5%)	0.062b
Smoking history, n (%)	11 (45.8%)	22 (55.0%)	0.651b
HbA1c, %	8.88 ± 1.58	8.63 ± 1.50	0.533a
Renal dysfunction, n (%)	9 (37.5%)	19 (47.5%)	0.603b
BMI, kg/m2	24.02 ± 2.76	22.98 ± 2.90	0.159a
Wound area, cm2	8.99 ± 1.78	8.50 ± 2.93	0.402a
Infection present, n (%)	10 (41.7%)	13 (32.5%)	0.638b
WIfI stage, n (%)			0.790c†
Stage 2	5 (20.8%)	7 (17.5%)
Stage 3	12 (50.0%)	18 (45.0%)
Stage 4	7 (29.2%)	15 (37.5%)
ABI	0.53 ± 0.08	0.55 ± 0.08	0.375a
TcPO₂, mmHg	28.88 ± 5.84	29.68 ± 4.84	0.575a
Prior ipsilateral revascularization, n (%)	5 (20.8%)	7 (17.5%)	0.751c

Data are presented as mean ± SD or n (%)

PTA, percutaneous transluminal angioplasty; TPD, tibial periosteal distraction; HbA1c, glycated hemoglobin; BMI, body mass index; ABI, ankle-brachial index; TcPO₂, transcutaneous oxygen pressure; WIfI, Wound, Ischemia, and foot Infection

ᵃIndependent-samples t test (Welch correction where appropriate)

ᵇPearson’s χ² test

ᶜFisher’s exact test

^†WIfI stage was compared as an overall categorical variable

Primary outcome and key secondary outcome

Kaplan–Meier analysis showed earlier complete wound healing in the PTA + TPD group than in the PTA-alone group (log-rank P < 0.001) (Fig. 3). In the crude Cox model, patients in the PTA + TPD group were more likely to achieve complete wound healing than those in the PTA-alone group (HR, 3.74; 95% CI 2.17–6.47; P < 0.001). After adjustment for prespecified baseline covariates, including WIfI stage, baseline wound area, and infection status, the association remained significant (adjusted HR, 3.90; 95% CI 2.23–6.83; P < 0.001) (Table 2). At 12 months, amputation-free survival (AFS) was 95.8% (23/24) in the PTA + TPD group and 82.5% (33/40) in the PTA-alone group, without a statistically significant between-group difference (P = 0.240) (Table 2).

Fig. 3.

Kaplan–Meier curves for time to complete wound healing in the PTA + TPD and PTA-alone groups

Table 2.

Primary and key secondary outcomes in the PTA + TPD and PTA-alone groups

Outcome	PTA + TPD (n = 24)	PTA-alone (n = 40)	Crude effect estimate (95% CI)	Adjusted effect estimate (95% CI)	P value
Time to complete wound healing, months, median (IQR)	2.04 (1.68–2.58)	3.26 (2.71–3.97)	HR 3.74 (2.17–6.47)	aHR 3.90 (2.23–6.83)	< 0.001a
12-month AFS, n/N (%)	23/24 (95.8)	33/40 (82.5)	OR 4.88 (0.56–42.38)		0.240b

Data are presented as median (IQR) or n/N (%)

AFS, amputation-free survival; CI, confidence interval; HR, hazard ratio; IQR, interquartile range; OR, odds ratio; PTA, percutaneous transluminal angioplasty; TPD, tibial periosteal distraction

^aTime to complete wound healing was analyzed using Kaplan–Meier analysis and Cox proportional hazards models. The crude hazard ratio (HR) and adjusted hazard ratio (aHR) with 95% confidence intervals (CIs) are shown. The adjusted model included prespecified baseline covariates: WIfI stage, baseline wound area, and infection status

^bCompared using Fisher’s exact test; OR was unadjusted

Secondary outcomes

Wound healing rates and recurrence

Wound outcomes at different follow-up time points are summarized in Table 3. At 3 months, the complete wound healing rate was 83.3% (20/24) in the PTA + TPD group and 52.5% (21/40) in the PTA-alone group, with a statistically significant between-group difference (P = 0.016). By 6 months, the complete wound healing rates were 95.8% (23/24) and 90.0% (36/40), respectively, with no statistically significant difference between groups (P = 0.642). During 12 months of follow-up, wound recurrence occurred in 12.5% (3/24) of patients in the PTA + TPD group and 30.0% (12/40) of those in the PTA-alone group, without a statistically significant between-group difference (P = 0.137). A representative case of wound healing after PTA plus TPD is shown in Fig. 4.

Table 3.

Secondary categorical outcomes in the PTA + TPD and PTA-alone groups

Outcome	PTA + TPD (n = 24)	PTA-alone (n = 40)	Effect estimate (95% CI)	P value
3-month complete wound healing, n/N (%)	20/24 (83.3)	21/40 (52.5)	OR 4.52 (1.31–15.63)	0.016a
6-month complete wound healing, n/N (%)	23/24 (95.8)	36/40 (90.0)	OR 2.56 (0.27–24.32)	0.642a
12-month wound recurrence, n/N (%)	3/24 (12.5)	12/40 (30.0)	OR 0.33 (0.08–1.33)	0.137a

Data are presented as n/N (%)

CI, confidence interval; OR, odds ratio; PTA, percutaneous transluminal angioplasty; TPD, tibial periosteal distraction

^aCompared using Fisher’s exact test; ORs are unadjusted

Fig. 4.

Representative case treated with PTA plus TPD. (A, B) Persistent non-healing wound with purulent exudate 2 months after toe amputation performed at another hospital. (C) PTA plus TPD combined with debridement, antibiotic-loaded bone cement coverage, and drainage. (D) Fresh granulation tissue at the 1-month follow-up. (E) Secondary wound closure with sutures. (F) Complete wound healing

Wound area trajectory

Longitudinal changes in wound area are shown in Fig. 5. Wound area declined in both groups, with a more rapid reduction in the PTA + TPD group. Linear mixed-effects modeling confirmed a significant group-by-time interaction (P for interaction < 0.001).

Fig. 5.

Longitudinal changes in wound area in the PTA + TPD and PTA-alone groups

Wound area declined in both groups, with a steeper reduction in the PTA + TPD group (P for interaction < 0.001).

Microcirculatory and perfusion-related indicators

Longitudinal changes in TcPO₂ and ABI are presented in Table 4. Linear mixed-effects modeling showed significant group-by-time interactions for both TcPO₂ and ABI (both P for interaction < 0.001), indicating more favorable perfusion-related trajectories in the PTA + TPD group over follow-up.

Table 4.

Longitudinal changes in TcPO₂ and ABI during follow-up

Outcome	Group	Baseline	1 month	3 months	6 months	P for interaction
TcPO₂, mmHg	PTA + TPD	28.9 ± 5.8	39.1 ± 6.1	45.8 ± 6.8	48.7 ± 6.9	< 0.001a
	PTA-alone	29.7 ± 4.8	36.5 ± 5.6	41.0 ± 5.8	42.8 ± 5.5
ABI	PTA + TPD	0.53 ± 0.08	0.69 ± 0.08	0.76 ± 0.07	0.79 ± 0.07	< 0.001a
	PTA-alone	0.55 ± 0.08	0.70 ± 0.08	0.75 ± 0.07	0.77 ± 0.06

Values are presented as mean ± SD

ABI, ankle-brachial index; TcPO₂, transcutaneous oxygen pressure; PTA, percutaneous transluminal angioplasty; TPD, tibial periosteal distraction

^aP for group-by-time interaction term in the linear mixed-effects model

Safety outcomes

Safety outcomes are summarized in Table 5. No statistically significant between-group differences were observed in the overall complication rate or reintervention rate (both P > 0.05). Treatment-specific adverse events were uncommon in both groups. In the PTA + TPD group, reported events included pin-tract/periosteal infection, pain intolerance, and device failure requiring reintervention. In the PTA-alone group, reported events included puncture-site hematoma, thrombosis, and embolism.

Table 5.

Safety outcomes in the PTA + TPD and PTA-alone groups

Outcome	PTA + TPD (n = 24)	PTA-alone (n = 40)	P value
Any complication, n/N (%)	5/24 (20.8)	5/40 (12.5)	0.482a
Reintervention, n/N (%)	1/24 (4.2)	0/40 (0)	0.375a

Values are presented as n/N (%)

PTA, percutaneous transluminal angioplasty; TPD, tibial periosteal distraction

^aFisher’s exact test

Discussion

In this retrospective cohort of patients with DFU and PAD/CLTI undergoing PTA, the addition of TPD was associated with faster complete wound healing, a higher 3-month healing rate, and more favorable trajectories of wound area, TcPO₂, and ABI during follow-up. By contrast, although 12-month amputation-free survival (AFS) was numerically higher in the PTA + TPD group, the between-group difference was not statistically significant (P = 0.240), and healing rates had converged by 6 months (P = 0.642). Taken together, these findings suggest that the main potential contribution of TPD may lie in accelerating early wound repair and support perfusion recovery after revascularization, rather than substantially altering later binary outcomes within the constraints of the present sample size and follow-up duration. Importantly, the association between PTA + TPD and earlier wound healing remained after limited adjustment for key baseline covariates. For less frequent endpoints influenced by multiple factors, including major amputation, death, and reintervention, the current study was likely underpowered to detect reliable between-group differences.

This pattern is clinically plausible. Current guidelines consistently emphasize that revascularization remains the foundation of limb-salvage treatment in patients with DFU complicated by PAD/CLTI [3, 7, 9]. However, technical success in restoring arterial patency does not necessarily ensure adequate perfusion at the wound level. Previous studies have shown that delayed healing may persist even after successful target-vessel recanalization, likely because distal tissue perfusion remains inadequate [11, 12]. In this setting, the therapeutic goal extends beyond reopening the artery itself to restoring a perfusion environment capable of supporting tissue repair [12, 21]. Delgadillo et al. further highlighted the potential importance of distal flow continuity between the dorsalis pedis and plantar arterial systems in translating revascularization into wound-healing benefit [22]. Within this framework, the present study did not compare two competing limb-salvage pathways, but rather examined whether TPD could provide additional benefit after standardized PTA. The more favorable trajectories of TcPO₂, ABI, and wound area in the PTA + TPD group are consistent with improved local perfusion, although this interpretation remains observational and should not be considered direct mechanistic evidence.

The present findings are also broadly aligned with the emerging literature on TPD. Prior studies have suggested that TPD may improve wound healing and perfusion-related indicators such as TcPO₂ and ABI in patients with moderate DFU [17], while more recent translational work combining animal and clinical data has linked TPD to improved perfusion and higher early- to mid-term healing rates [14]. Related evidence from tibial transverse transport (TTT) likewise supports the biological plausibility of this approach. Prospective multicenter studies and meta-analyses have suggested TTT may improve wound healing, perfusion, and limb salvage [23, 24], thereby providing indirect support for the concept that local tibial distraction may confer distal perfusion benefits. Ou et al. further reported that TTT was associated with improved blood circulation in the affected limb, accompanied by early increases in angiogenesis-related factors such as vascular endothelial growth factor, basic fibroblast growth factor, epidermal growth factor, and platelet-derived growth factor [25]. At the same time, most previous studies have evaluated TPD or TTT as relatively independent limb-salvage techniques rather than as adjuncts to revascularization. Direct comparative evidence for the addition of TPD after PTA therefore remains limited. Although an earlier case report suggested that periosteal distraction might still be beneficial in a patient with CLTI and persistent non-healing after multiple revascularization procedures [26], such evidence is primarily hypothesis-generating and cannot substitute for comparative cohort data. In this context, the main contribution of the present study is to provide preliminary clinical evidence for TPD as a post-revascularization adjunct rather than to support any definitive claim of efficacy.

Based on the present findings, TPD may be more appropriately positioned as a planned adjunct after PTA rather than as an independent alternative to revascularization. In patients with DFU complicated by PAD/CLTI, following technically successful PTA during the index hospitalization, tibial periosteal distraction may be considered an adjunctive treatment option incorporated into the initial limb-salvage pathway, rather than a salvage procedure introduced later in response to delayed healing. This interpretation is consistent with current guideline frameworks, in which healing-promoting interventions are built on standardized multidisciplinary care and restoration of blood flow rather than used to replace these core components [3, 13]. Modern diabetic foot management extends beyond restoration of blood flow alone. When clinically relevant, evidence-based management of diabetic foot osteomyelitis and adequate off-loading remain important co-interventions within a multidisciplinary limb-salvage pathway [27–29]. In the present study, although 12-month AFS was numerically higher in the PTA + TPD group, the between-group difference was not statistically significant. By contrast, time to complete wound healing and the 3-month healing rate appeared to be more informative indicators of early treatment benefit. The convergence of healing rates by 6 months further suggests that the principal contribution of TPD in this setting may be to accelerate the healing process rather than to materially change the eventual likelihood of wound healing. These findings should nevertheless be interpreted cautiously, because allocation to TPD reflected multidisciplinary clinical decision-making and patient acceptance rather than randomization. In addition, this study was not designed to compare TPD with other adjunctive strategies, such as hyperbaric oxygen therapy, and the observed early healing advantage should therefore not be interpreted as evidence of superiority over less invasive adjunctive options.

In terms of safety, the present study did not identify a clear increase in overall complications or reintervention, suggesting that TPD may be feasible when applied in appropriately selected patients under standardized perioperative management. Compared with TTT, which requires corticotomy or segmental bone transport, TPD does not involve complete bony division and may therefore reduce osseous trauma and perioperative burden in theory [16]. However, given the limited sample size and the small number of treatment-specific complications, the current data are insufficient to support any definitive conclusion regarding safety. In addition, procedural parameters such as the latency period, distraction rate, and total distraction distance may influence both patient tolerance and treatment effect. Accordingly, even if TPD provides additional benefit, its broader application should remain contingent on careful patient selection, standardized perioperative care, and individualized adjustment of procedural parameters.

Limitations and future directions

This study has several limitations. First, the single-center retrospective design introduces the possibility of selection bias and residual confounding. Because TPD was performed as a staged procedure after PTA rather than on the same date, time-dependent treatment bias, including potential immortal time bias, cannot be excluded. In addition, allocation to TPD reflected multidisciplinary clinical decision-making and patient acceptance rather than randomization, and confounding by indication therefore remained possible. Target-vessel selection and procedural success assessment were also not prospectively standardized, and formal subgroup analysis according to revascularization strategy was therefore not possible. In particular, although operative records and wound location allowed a rough retrospective classification of direct versus indirect revascularization in some cases, this information had not been prospectively recorded using standardized criteria and was therefore not considered sufficiently robust for formal analysis. Quantitative residual stenosis thresholds, formal angiographic runoff scores, standardized pedal arch assessment, and immediate post-PTA ABI improvement were also not consistently available for retrospective analysis. Moreover, this study was not designed to compare TPD with other adjunctive therapies, such as hyperbaric oxygen therapy, and the observed early healing advantage should not be interpreted as evidence of superiority over less invasive adjunctive strategies. Second, the sample size was modest, and major amputation, death, and reintervention were infrequent, limiting statistical power for these outcomes. Third, although TcPO₂ and ABI are useful for longitudinal assessment of perfusion-related change, they remain surrogate measures and do not fully capture tissue-level microcirculatory reconstruction. Fourth, follow-up was mainly limited to 12 months and was therefore insufficient to assess longer-term recurrence, reintervention burden, and functional outcomes. Fifth, key TPD parameters, including the latency period, distraction rate, and total distraction distance, have not yet been fully standardized, and their effects on tolerance and efficacy remain uncertain. Larger multicenter prospective studies are needed to clarify the target population, optimal timing, revascularization strategy, comparative role versus other adjunctive options, and optimal procedural parameters of TPD after PTA.

Conclusion

In patients with DFU complicated by PAD/CLTI, the addition of TPD after PTA was associated with faster wound healing and more favorable perfusion-related changes during follow-up. TPD may have value as a post-revascularization adjunct. Larger multicenter prospective studies are needed to confirm these findings and to clarify its long-term efficacy, optimal indications, and procedural parameters.

Author contributions

J.L. and S.X. contributed equally to this work. S.X., S.Z., and W.L. conceived and designed the study. J.L., W.G., C.L., C.C., Q.H., D.Z., and Z.L. screened eligible patients, collected the clinical data, and coordinated follow-up. J.L., S.X., Z.L., and W.L. verified the data and adjudicated the study endpoints. J.L. and W.L. performed the statistical analyses and drafted the manuscript. S.X., S.Z., and W.L. critically revised the manuscript for important intellectual content and supervised the study. All authors read and approved the final manuscript.

Funding

This work was supported by Startup Fund for scientific research, Fujian Medical University (Grant No. 2019QH1220). The funders had no role in the study design; data collection, analysis, or interpretation; manuscript preparation; or the decision to submit for publication.

Data availability

The datasets used and/or analyzed during the current study are available from the corresponding author upon reasonable request.

Declarations

Ethics approval and consent to participate

The study protocol was approved by the Institutional Review Board of the Affiliated Mindong Hospital of Fujian Medical University (IRB No. K2026031901) and was conducted in accordance with the Declaration of Helsinki. The requirement for informed consent to participate was waived because of the retrospective design and the use of anonymized data.

Consent for publication

Written informed consent for publication of the clinical images was obtained from the patient.

Clinical trial registration

Not applicable.

Competing interests

The authors declare that they have no competing interests.