Single lag-screw–augmented dorsal plating yields superior union and lower costs in first metatarsophalangeal arthrodesis

Abstract

Objective:

This study aimed to compare clinical outcomes and total treatment costs of 3 fixation strategies—isolated dorsal plating, dorsal plating with a single lag screw, and dorsal plating with dual lag screws—in patients undergoing first metatarsophalangeal (MTP) joint arthrodesis for advanced hallux rigidus.

Methods:

This retrospective study included 99 patients who underwent primary first MTP joint arthrodesis between 2019 and 2024. Patients were categorized into Group 1 (dorsal plate only; n = 27), Group 2 (plate + 1 lag screw; n = 42), and Group 3 (plate + 2 lag screws; n = 30). Demographic variables, radiographic union, revision rates, functional outcomes (American Orthopaedic Foot and Ankle Society [AOFAS], Visual Analog Scale [VAS], Foot Function Index [FFI]), and total 12-month treatment costs were evaluated. The primary outcome measures were union rate, time to union, revision surgery, functional scores, and cumulative cost.

Results:

Group 1 demonstrated significantly lower union rates compared with Groups 2 and 3 (88.9% vs. 100% for both; P = .027) and a longer mean time to union (75 days vs. 65.8 and 62 days, respectively; P = .001). Revision surgery was required only in Group 1 (11.1%). The AOFAS scores were significantly higher in the screw-augmented groups (P = .013), while VAS and FFI scores showed no between-group differences. Cost analysis identified Group 2 as the most cost-effective strategy (9500 ± 1100 TL ≈ $310 ± 36), compared with Group 1 (11 200 ± 1400 TL ≈ $365 ± 46, P = .021) and Group 3 (11 600 ± 1300 TL ≈ $378 ± 42, P = .038).

Conclusion:

Single lag-screw augmentation of dorsal plate fixation provides superior union, fewer revisions, improved functional scores, and the lowest overall 12-month cost. These findings support dorsal plating with a single lag screw as a practical, value-based fixation strategy for advanced hallux rigidus, offering optimal clinical and economic outcomes.

Level of Evidence

: Level III, Therapeutic Study.

Highlights

• The combination of a dorsal plate and a single lag screw has yielded the most favorable clinical outcomes, with a 100% union rate and no revision surgeries.

• In patients treated with dorsal plates alone, fusion times were longer, and revision rates were higher.

• From a clinical perspective, the current study suggests that dorsal plate fixation augmented with a single lag screw may represent the most practical and value-based choice, as it achieves reliable union and reduces revision risk without unnecessary implant costs.

Introduction

Hallux rigidus (HR) is the progressive degenerative arthritis of the first metatarsophalangeal (MTP) joint that leads to pain, reduced range of motion (ROM), and impaired gait.¹Joint preservation becomes impossible in advanced stages, particularly stage 4, and arthrodesis is the only viable treatment option.²The goal of the first MTP joint arthrodesis is to achieve a painless, plantigrade, and stable fusion. To accomplish this, various fixation techniques have been developed, most commonly involving dorsal locking plates (DLP) with or without the use of supplemental lag screws.^3,4

Biomechanically, DLPs oppose shear and twisting forces, and lag screws add compression at the fusion site. Thus, the combination of plates and lag screws has become popular.⁵However, the incremental benefit of using 1 versus 2 lag screws remains uncertain. Implant selection also depends on factors such as fusion stability, which in turn influences cost, operative time, and complication risk.

Although DLP-only constructs seem cost-effective and require fewer implants, clinical observations indicate that they are associated with a greater risk of implant failure and reoperation.⁶The unplanned interventions may incur substantial hidden costs. In contrast, dual lag screw constructs, although they raise implant costs and surgical time,⁷ may not significantly enhance union rates and functional outcomes compared with simpler configurations.⁸

A central concern in medicine is to maintain quality while minimizing cost. Previous cost analyses have demonstrated that implant choice substantially influences the economic burden of first MTP arthrodesis. For instance, Filomeno and López⁷ compared DLP versus crossed screw fixation and found no differences in functional outcomes, while plate constructs were nearly 8 times more expensive. Such findings emphasize that higher implant cost does not necessarily translate into superior clinical benefit, underscoring the importance of value-based assessment in fixation strategy selection.

To date, no study has comprehensively evaluated the clinical outcomes and total cost burden of these 3 commonly used fixation methods (DLP alone, DLP with 1 lag screw, and DLP with 2 lag screws) over a standardized 12-month follow-up. There is a growing need for evidence that combines clinical outcomes with economic analyses to guide value-based decision-making in foot and ankle surgery. This study aims to fill that gap by comparing union rates, revision needs, functional outcomes, and total cost across 3 fixation strategies: DLP alone, DLP with 1 lag screw, and DLP with 2 lag screws. The current study hypothesizes that although DLP-only fixation appears to be the least expensive option upfront, the need for revision surgery drives its total cost close to that of the dual lag screw group. The most cost-effective and clinically balanced strategy is expected to be the combination of DLP and a single lag screw, which minimizes revision rates without increasing implant burden.

Materials and methods

Study design and patient selection

This retrospective cohort study was conducted at a tertiary healthcare center’s orthopedics and traumatology department. Between January 2019 and January 2024, patients who underwent MTP joint arthrodesis due to stage 4 HR were included in the study. This study was approved by the Fırat University Faculty of Medicine Clinical Research Ethics Committee (Approval No.: 2024/09-28; Date: June 6, 2024). Informed consent was obtained from all individuals included in the study. All surgeries were performed by the same orthopedic surgical team using standardized preoperative, intraoperative, and postoperative protocols. As this was a retrospective study, the sample size was determined by all consecutive patients meeting the inclusion and exclusion criteria during the study period. No a priori power analysis was performed.

Patients were included if they met the following criteria: (1) diagnosis of stage 4 HR according to the Coughlin and Shurnas classification, (2) surgical fixation with a DLP with or without lag screw augmentation, and (3) availability of complete clinical and radiological follow-up data for at least 12 months. Exclusion criteria included (1) inflammatory arthropathies, including rheumatoid arthritis, (2) malpositioned arthrodesis (defined as >10° deviation in either valgus or dorsiflexion), (3) use of non-standardized implants, and (4) incomplete hospital records. Moreover, no patients with additional forefoot pathologies were included; such cases were excluded from the analysis. Baseline demographic variables such as age, sex, body mass index, diabetes mellitus, and smoking status were systematically recorded for all patients to allow proper characterization of the study population. Based on the method of fixation employed, patients were grouped into 3 divisions, namely, Group 1 (DLP alone), Group 2 (DLP with 1 lag screw), and Group 3 (DLP with 2 lag screws).

Surgical procedure

All procedures were performed under spinal anesthesia with a thigh tourniquet applied. A medial longitudinal incision was made over the first MTP joint. Following removal of osteophytes and inflamed soft tissue, the articular surfaces of the metatarsal head and proximal phalanx were debrided using a rongeur to expose the subchondral bone. Intramedullary subchondral drilling was performed using a 1.2 mm drill (Figure 1). A sterile surgical instrument tray was placed beneath the foot to assist with positioning and maintain the desired dorsiflexion angle. Under intraoperative fluoroscopic guidance and using the second toe as a reference, the hallux was aligned in 5°-10° of dorsiflexion and slight valgus (Figure 2). Temporary fixation was achieved using Kirschner wires.

Figure 1.

Subchondral drilling performed to promote fusion with the help of a drill by entering the intramedullary area from the joint surfaces. a: first metatarsal joint surface. b: proximal phalanx joint surface.

Figure 2.

Placing the surgical instrument tray on the sole of the foot during dorsiflexion adjustment of the first toe in arthrodesis surgery, temporary fixation with a Kirschner wire after providing appropriate height and angle.

In Group 1, fixation was achieved with a DLP (2.7 mm, TST, Istanbul) alone. In Group 2, 1 headless cannulated lag screw (3.3 mm) was inserted across the fusion site before applying the plate. In Group 3, 2 crossed lag screws were used in combination with the DLP (Figure 3). All implants used were of the same brand and specifications to ensure methodological consistency. Plate fixation was performed with 3 locking screws on the proximal phalanx side and 2-3 locking screws on the metatarsal side, depending on bone quality and intraoperative stability. Although this variation could theoretically influence implant costs, it was considered unlikely to significantly impact group-level cost comparisons. These fixation configurations were chosen as they correspond to the constructs most widely employed in routine first MTP arthrodesis, allowing comprehensive clinical and cost-based comparisons.

Figure 3.

a: Patient in the first group using only the dorsal plate. b: Patient in group 2 with dorsal plate and 1 lag screw. c: Patient in group 3 with dorsal plate and 2 cross lag screws.

Postoperative rehabilitation

All patients received 1 g intravenous cefazolin 30 minutes before surgery, followed by scheduled doses for the first 24 postoperative hours. A below-knee posterior splint was applied immediately after surgery. Patients were advised to remain non–weight-bearing with crutches for the first 30 days. Sutures were removed at 15 days, and heel-only walking without forefoot loading was permitted until postoperative day 30, using a rigid-sole postoperative shoe to enable protected ambulation during this phase. Full weight bearing was allowed after radiographic confirmation of union and clinical resolution of pain.

Clinical and radiological evaluation

Radiographs were taken on postoperative days 15, 30, and 60 and at 6 and 12 months. Radiographic union was defined as the presence of bone trabeculae across at least 3 cortices, along with the absence of rest pain. Functional outcomes were assessed using the Visual Analog Scale (VAS) for pain, the Foot Function Index (FFI), and the American Orthopaedic Foot and Ankle Society (AOFAS) score. Evaluations were performed both preoperatively and at the 12-month follow-up.

Patients who experienced implant failure or nonunion were included in the complication analysis as well as the functional outcome comparisons to prevent selection bias and reflect real-world outcomes. Subgroup analyses were conducted where relevant.

Cost analysis

The cost analysis was conducted from the healthcare provider’s perspective and included all direct medical expenses incurred from the day of hospital admission until discharge. Cost data were collected retrospectively from institutional patient billing records. For each patient, the total cost covered implant materials, surgical procedures, anesthesia, hospitalization, medications, laboratory tests, radiographs, and outpatient follow-up visits over a 12-month period. For each group, the mean total cost per patient was calculated by dividing the sum of all individual patient costs by the number of patients in that group. Standard deviations were calculated from the distribution of individual patient costs.

In cases requiring revision surgery, the additional hospitalizations were recorded as separate episodes. The cost of each subsequent admission—including reoperation, new implants, extended hospital stay, antibiotic therapy, and any ancillary care—was added to the patient’s total cumulative cost. For the cost decomposition, the per-revision unit cost was anchored to the institution’s bundled tariff for forefoot revision arthrodesis during the study period and set at 12 000 Turkish Lira (TL) (covering operating room, anesthesia, inpatient care, and implant removal/re-arthrodesis). This value was used to estimate the revision-attributable portion of total costs. All cost values were calculated in TL and reflect actual charges as billed by the institution during the study period. For international comparability, costs were additionally expressed in United States Dollars (USD), calculated using the average annual USD/TL exchange rate corresponding to each patient’s surgery year (2019-2024). All statistical analyses were performed on TL values, while USD conversions were provided for readability. Indirect or non-medical costs such as transportation, loss of income, or caregiver burden were not included in this analysis.

Statistical analysis

All statistical analyses were performed using IBM SPSS Statistics version 22 (IBM Corp., Armonk, NY, USA). The normality of continuous variables was assessed with the Shapiro–Wilk test. Age, body mass index (BMI), and time to union were compared among groups using one-way ANOVA, with Tukey’s honestly significant difference test for post-hoc pairwise comparisons. Union rates, sex distribution, diabetes mellitus, smoking status, and complication rates were analyzed using chi-square or Fisher–Freeman–Halton tests, as appropriate. Cost data were compared using one-way ANOVA with Tukey’s HSD post-hoc test. Pre- and postoperative functional scores (AOFAS, VAS, FFI) within each group were analyzed using the Wilcoxon signed-rank test. A P-value < .05 was considered statistically significant.

Results

Baseline characteristics

The study included a total of 99 patients with stage 4 HR who underwent arthrodesis for the first MTP joint. On the basis of fixation techniques, the patients were grouped into 3 groups: Group 1 (DLP only, n = 27), Group 2 (DLP with 1 lag screw, n = 42), and Group 3 (DLP with 2 crossed lag screws, n = 30).

The average age was somewhat higher among Group 1 (54.3 ± 7.4 years) than either Group 2 (52.3 ± 4.4 years) or Group 3 (52.1 ± 5.3 years), but the difference was not statistically significant (P = .799). Similarly, BMI (P = .709), prevalence of diabetes mellitus (P = .700), and smoking status (P = .650) did not differ among the groups (P > .05 for all). There was a significant difference in gender distribution across groups (P = .033). Further demographic and clinical characteristics can be found in Table 1.

Table 1.

Demographic, radiological, and complication data

Variables	Group 1 (plate only)	Group 2 (plate + 1 lag screw)	Group 3 (plate + 2 lag screws)	P
Demographic and radiological variables	27	42	30	–
Age (mean ± SD, years)	54.3 ± 7.4	52.3 ± 4.4	52.1 ± 5.3	.799
Male, n (%)	18 (66.7)	28 (66.7)	11 (36.7)	.033
Female, n (%)	9 (33.3)	14 (33.3)	19 (63.3)	.033
BMI (mean ± SD, kg/m²)	28.0 ± 3.2	28.1 ± 3.1	28.4 ± 3.3	.709
Diabetes mellitus, n (%)	9 (33.3)	16 (38.1)	10 (33.3)	.700
Smoking, n (%)	11 (40.7)	16 (38.1)	10 (33.3)	.650
Radiographic union rate (%)	88.9	100	100	.027
Mean time to union (days)	75.0 ± 6.5	65.8 ± 7.1	62.0 ± 6.8	.001
Implant failure/Revision surgery, n (%)	3 (11.1)	0 (0)	0 (0)	.027
Superficial infection, n (%)	2 (7.4)	1 (2.4)	1 (3.3)	.735

One-way ANOVA was used for continuous, normally distributed variables (age, BMI, time to union). The chi-square test (or Fisher’s exact test where appropriate) was applied for categorical variables (sex, diabetes mellitus, smoking, union rate, complications). P-value of <.05 was considered statistically significant.

The year-wise distribution of patients is presented in Table 2. A total of 14 patients (14.1%) underwent surgery in 2019, while only 5 patients (5.1%) were operated on in 2020, reflecting the impact of the COVID-19 pandemic, during which elective surgical procedures were markedly reduced. The numbers increased again in subsequent years, with 18 patients (18.2%) in 2021, 22 patients (22.2%) in 2022, 22 patients (22.2%) in 2023, and 18 patients (18.2%) in 2024. Statistical comparison demonstrated no significant difference in the temporal distribution among the 3 fixation groups (χ² test, P = .999). This finding indicates that the uneven distribution of cases over time did not bias the cost and outcome analyses.

Table 2.

Year-wise distribution of patients across groups (2019-2024)

Year	Group 1 (plate only)	Group 2 (plate + 1 lag screw)	Group 3 (plate + 2 lag screws)	Total
2019	4	6	4	14
2020	1	2	2	5
2021	5	8	5	18
2022	6	9	7	22
2023	6	9	7	22
2024	5	8	5	18
Total	27	42	30	99

Chi-square analysis revealed no statistically significant difference among the groups regarding year of surgery (P = .999).

Radiological outcomes

At the 12-month follow-up, the radiographic union rate for all patients was 95.9%. The union rate in Group 1 (DLP only) was significantly lower at 88.9%, while both Group 2 (DLP with 1 lag screw) and Group 3 (DLP with 2 lag screws) achieved a 100% union rate (P = .027).

Group 1 had a significantly longer time to radiographic union (75.0 ± 6.5 days) compared with Group 2 (65.8 ± 7.1 days) and Group 3 (62.0 ± 6.8 days) (P < .001). Post-hoc analysis confirmed that Group 1 differed significantly from both Group 2 and Group 3 (P < .001 for both), whereas no significant difference was found between Group 2 and Group 3 (P = .214).

Complications

The highest incidence of implant-related complications was present in Group 1, with dorsal plate fixation only. In this group, 3 patients (11.1%) sustained implant failure and were treated with revision arthrodesis for symptoms of nonunion or hardware loosening (Figure 4). Additionally, implant-related discomfort was recorded in 3 patients from Group 1, all of whom later underwent implant removal. Implant-related discomfort was not observed in either Group 2 or Group 3, and no revisions were required in either group. The difference in revision rates among the groups was statistically significant (P = .027). Regarding malposition, 2 patients initially treated with a dorsal plate only (Group 1) developed >10° deviation in valgus or dorsiflexion and were therefore excluded from the final analysis. No cases of malposition were identified in Groups 2 or 3. Two patients in Group 1, 1 patient in Group 2, and 1 patient in Group 3 developed superficial surgical site infections. All were resolved with oral antibiotics and local wound care, and there were no cases requiring surgical intervention. No deep infections, wound dehiscence, or neurovascular complications were noted in any group.

Figure 4.

Patients who underwent arthrodesis with dorsal plate only and developed implant failure. a: Patient 1. b: Patient 2. c: Patient 3.

Functional outcomes

At the 12-month follow-up, statistically significant differences in AOFAS scores were observed among the groups (P = .013). Group 1 demonstrated significantly lower AOFAS scores than Groups 2 and 3 (81.3 ± 9.5 vs 88.7 ± 7.8 and 89.2 ± 8.0; P = .018 and P = .012, respectively), while scores did not differ significantly between Groups 2 and 3 (P = .874).

In contrast, no significant differences were found in VAS pain scores (Group 1: 2.4 ± 1.1, Group 2: 2.0 ± 1.2, Group 3: 1.9 ± 1.0; P = .237) or in FFI scores (Group 1: 36.7 ± 7.8, Group 2: 34.2 ± 6.9, Group 3: 33.8 ± 6.7; P = .281) (Table 3). These findings suggest that although overall pain levels and general foot function were similar across groups, patients in the lag-screw–augmented groups achieved superior standardized functional scores, as reflected by higher AOFAS scores.

Table 3.

Functional outcome scores

Scores	Group 1 (plate only)	Group 2 (plate + 1 lag screw)	Group 3 (plate + 2 lag screws)	P
AOFAS Score (mean ± SD)	81.3 ± 9.5	88.7 ± 7.8	89.2 ± 8.0	.013
VAS Score (mean ± SD)	2.4 ± 1.1	2.0 ± 1.2	1.9 ± 1.0	.237
FFI Score (mean ± SD)	36.7 ± 7.8	34.2 ± 6.9	33.8 ± 6.7	.281

Data are presented as mean ± SD. One-way ANOVA was used for between-group comparisons. P-value <.05 was considered statistically significant.

AOFAS, American Orthopaedic Foot and Ankle Society Score; VAS, Visual Analog Scale; FFI, Foot Function Index.

Cost analysis

Cumulative clinical records were analyzed to determine total treatment costs per patient, covering all direct medical expenses from initial hospital admission through 12-month follow-up. Regarding costs, Group 1 (DLP only) had a total mean expense of 11 200 ± 1400 TL (≈ $365 ± 46, year-adjusted), while Group 2 (DLP + 1 lag screw) had the lowest mean expense from total costs at 9500 ± 1100 TL (≈ $310 ± 36, year-adjusted). Group 3 (DLP + 2 lag screws) had the highest cumulative cost at 11 600 ± 1300 TL (≈ $378 ± 42, year-adjusted) (Table 4). All statistical comparisons were performed on TL values, and the relative cost advantage of Group 2 remained unchanged after year-adjusted USD conversion.

Table 4.

Pairwise cost comparison between groups

Group	Mean total cost (₺ ± SD)	Mean total cost (USD ± SD, year-adjusted)	Median cost (₺)	P vs Group 1	P vs Group 2
Group 1 (plate only)	11 200 ± 1400	365 ± 46	11 000	–	.021
Group 2 (plate + 1 lag screw)	9500 ± 1100	310 ± 36	9400	.021	–
Group 3 (plate + 2 lag screws)	11 600 ± 1300	378 ± 42	11 500	.754	.038

Total costs compared using one-way ANOVA followed by Tukey post-hoc tests. P-value < .05 was considered statistically significant. USD values were calculated using the average annual USD/TRY exchange rate of the respective surgery year (2019-2024). All statistical comparisons were performed on TL values.

Minor variation existed in the number of screws used for plate fixation (5-6 in total, with 3 placed on the proximal phalanx side and 2 or 3 on the metatarsal side). This difference could slightly affect implant costs; however, this was unlikely to materially influence the comparative analysis, as screw costs represented a relatively small portion of total treatment expenses.

To quantify the contribution of revisions, the total cost was decomposed into index and revision components using the institutional per-revision unit cost of 12 000 TL. In Group 1, 3 revisions among 27 patients translated to a mean revision-attributable burden of ~1333 TL** per patient (36 000/27). Subtracting this amount yielded an adjusted index mean of ~9867 TL for Group 1 (observed total 11 200 TL − 1333 TL) versus 9500 TL for Group 2. Thus, revisions explain a large share of the original G1-G2 gap, while the residual difference (~300 TL) likely reflects non-revision resource use associated with longer time to union in Group 1 (e.g., additional outpatient visits and radiographs). All hypothesis testing remained based on original TL totals (Table 5).

Table 5.

Decomposition of total cost into index and revision components (mean; TL/USD, year-adjusted)

Group	Index cost (TL/USD)	Revision cost (TL/USD)	Total cost (TL/USD)	Share of G1-G2 gap explained by revisions (%)
G1	9867 / $319	1333 / $44	11 200 / $365	~78 (1333/1700 TL)
G2	9500 / $310	0 / $0	9500 / $310	–
G3	11 600 / $378	0 / $0	11 600 / $378	–

The difference in total cost was statistically significant between Group 2 and both Group 1 (P = .021) and Group 3 (P = .038), supporting the economic advantage of single lag screw augmentation. Median cost values followed a similar pattern: 11 000 TL in Group 1, 9400 TL in Group 2, and 11 500 TL in Group 3, further reinforcing the cost-efficiency of Group 2.

Discussion

This investigation provides a comprehensive comparison of the clinical and economic performance of the 3 most commonly used fixation strategies for first MTP arthrodesis. The current study found that supplementing DLP constructs with a single lag screw not only optimizes fusion rates and functional outcomes but also has the most favorable cost profile after 1-year follow-up. Although DLP-only fixation is often considered cost-effective due to lower implant requirements, cumulative analysis revealed that revision-related expenditures increased its total treatment cost to a level comparable with the more complex dual-screw configuration. By contrast, the DLP + 1 lag screw group achieved 100% union, had no revision cases, and yielded the lowest overall cost per patient, establishing it as the most efficient and clinically reliable approach among the 3 techniques.

Based on the study data, using a DLP alone was associated with lower fusion rates and prolonged time to union, whereas the addition of lag screw augmentation—either single or double—significantly improved outcomes, with both augmented groups achieving 100% union. These findings corroborate the biomechanical rationale that interfragmentary compression promotes osseous consolidation when combined with dorsal locking plate fixation.^9,10Interestingly, no statistically significant difference was observed between the single and double lag screw groups in terms of union rate or fusion time. This suggests that the addition of a single lag screw may be sufficient to achieve adequate fixation stability. Cone et al⁵demonstrated that adding a single lag screw to a DLP may offer enhanced stability without significantly improving fusion rates. However, unlike the present study, they did not investigate whether a second screw provides additional clinical benefit. In line with the current study, Harris et al¹¹reported that the addition of a lag screw to a DLP significantly enhances the rigidity of the construct, particularly in resisting multiplanar loading forces during gait. Likewise, a prospective cohort study by Latif et al¹²evaluated a low-profile titanium plate incorporating a lag compression screw for first MTP joint arthrodesis in patients with HR. The study reported a 100% union rate with minimal complications, suggesting that such augmented constructs can yield excellent outcomes. In contrast, Restuccia et al¹³reported that fixation with a DLP alone achieved a 90% union rate, which was comparable to other methods, indicating that plate-only constructs may still be effective in certain cases. Similarly, a study by Dureja et al¹⁴reviewed 12 MTP joint fusions using a single intramedullary screw and found a 100% fusion rate, suggesting that simpler fixation methods can also yield high success rates. Although both Restuccia et al ¹³ and Dureja et al ¹⁴ report high union rates using DLP alone and intramedullary devices, respectively, neither study includes a control group or direct comparison with augmented fixation. Moreover, the small sample size (n = 12) and short follow-up in the series by Dureja et al ¹⁴ limit the extent to which their reported 100% union rate can be generalized. Therefore, while the theoretical biomechanical superiority of multiple screws is acknowledged, the findings indicate that no additional clinical advantage was observed with the use of a second lag screw. Beyond screw-augmented plate constructs, recent investigations have also evaluated alternative fixation materials in foot and ankle surgery. O’Neill et al¹⁵ reported that biointegrative implants achieved union rates, complication profiles, and patient-reported outcomes comparable to traditional metal implants across midfoot and hindfoot procedures. Although their study examined a different anatomic region and implant type, their findings similarly support the notion that implant material or design alone does not necessarily translate into superior clinical outcomes. This aligns with the present study, which demonstrates that adding a second lag screw—despite theoretically increasing construct stability—does not provide additional measurable clinical benefit.

At the 12-month follow-up, patients in both groups who had augmentation with the lag screw (Groups 2 and 3) had much higher AOFAS scores as compared with those treated with DLP alone. However, no clinically relevant difference was seen between single and dual-screw augmentation, implying that a single lag screw may be sufficient for optimal functional recovery. This is consistent with the biomechanical hypothesis that interfragmentary compression improves the stability of fusion and that a single screw associated with rigid dorsal plating is sufficient to provide adequate compression. Notably, this discrepancy in AOFAS scores was accompanied by a lack of difference in VAS and FFI scores between the 2 groups. This disparity may reflect the nature of the measuring instruments used. AOFAS includes clinician-based assessments such as joint alignment, ROM, and stability, which may detect subtle biomechanical improvements following screw augmentation.¹⁶In contrast, VAS and FFI are entirely patient-reported and primarily assess subjective pain and disability, which may plateau across different fixation constructs once a baseline level of recovery is achieved.

Based on the existing literature, this is the first clinical study to directly compare DLP fixation augmented with 1 versus 2 lag screws in the first MTP joint arthrodesis. Although previous studies have demonstrated that adding a lag screw to a DLP improves stability and union rates, none have specifically addressed whether adding a second screw yields additional benefit. For instance, Claassen et al⁴compared crossed screw fixation with locking and non-locking plates augmented with a single lag screw; they did not consider the dual-screw configurations. Daszkiewicz et al ¹⁷ performed a biomechanical evaluation of medial and dorsal plate fixation systems augmented by a single lag screw, but did not extend their work to multiple screw configurations. Finally, the systematic review by Balu et al¹⁸also argued in favor of the biomechanical superiority of plate and screw constructs regardless of whether there is 1 or 2 screws used. When combined, the current study addresses a significant gap in the literature by demonstrating that while lag screw augmentation enhances functional outcomes compared to dorsal plating alone, the addition of a second screw does not significantly boost clinical benefits. This insight may guide surgeons toward more efficient, cost-effective fixation strategies without compromising patient recovery.

From an economic perspective, the total treatment costs associated with a single lag screw augmentation (Group 2) were significantly lower than those of both the DLP-only group (Group 1) and the dual lag screw group (Group 3), without compromising the clinical outcomes. Although Group 2 had higher initial implant costs than Group 1, the absence of revision surgeries and shorter time to union offset these expenses, making it the most cost-effective construct over the follow-up period. This is supported by the findings of Filomeno et al,⁷ who compared DLP + screw fixation with crossed screws during first MTP arthrodesis and found no difference in the AOFAS or VAS scores, although the dorsal plate construct was almost 8 times more expensive. Their conclusion was clear: “Using implants 8 times more expensive does not lead to better clinical results,” emphasizing the importance of cost-efficiency in standard clinical scenarios. The results of the present study conflict with those of Lim et al,¹⁹ wherein a recent meta-analysis has shown no clinically significant differences between dorsal plating with lag screw and simpler crossed screw constructs, despite higher implant costs. Importantly, Lim et al ¹⁹ reinforced the argument that more complex fixation is not inherently better than a simpler method that provides similar union and complication rates. Adding further nuance, Hyer et al²⁰showed that DLP fixation incurred significantly higher implant costs than crossed screws, with no improvement in outcome scores. They suggested that, from an economic standpoint, simpler screw constructs may be more appropriate in routine cases of hallux surgery. Similarly, Rothermel et al²¹ demonstrated that synthetic hydrogel implants, while beneficial for pain and function, were associated with significantly higher costs compared to first MTP arthrodesis, underlining that increased implant expense does not necessarily translate into greater clinical value. Likewise, Haimes et al²²compared the costs and complications associated with the first MTP arthrodesis in terms of the available locked versus non-locked plate fixation constructs. This corresponds to an approximate extra cost from surgeries utilizing DLPs of about $1500 compared to those using non-locking plates, even though the nonunion or need for revision remained statistically similar. This suggests that the routine use of more expensive locking plates may not be economically justified. Based on the existing literature, no previous studies have specifically conducted a cost analysis comparing isolated DLP versus DLP with single or dual lag screw augmentation for first MTP arthrodesis. Therefore, the current study provides novel insight, demonstrating that while isolated dorsal plating initially appears less costly, single lag screw augmentation becomes the most cost-effective construct when postoperative revision rates and union times are considered at the 1-year follow-up. Although all statistical analyses were performed on TL values, costs were also expressed in USD using year-adjusted exchange rates to allow international comparability. Importantly, the relative cost advantage of the single lag screw group remained unchanged after this conversion. This key finding underscores the importance of evaluating long-term economic implications rather than initial implant expenses alone.

During the study period, dorsal plate constructs—either isolated or combined with lag screws—were the standard fixation method at the treating institution. This institutional preference was largely based on the perceived advantages of plate constructs in providing rotational stability, facilitating correction in cases with deformity, and allowing lag screw augmentation when additional stability was required. As a result, crossed screw fixation was not routinely performed and was therefore not represented in the study cohort. Nevertheless, current literature indicates that crossed screws may achieve comparable union rates and clinical outcomes at a lower implant cost. Recent reports, including those by Lim et al¹⁹ and Hyer et al,²⁰ emphasize that screw-only constructs represent a cost-effective alternative to plating, without compromising stability or fusion success. While the present data are limited to plate-based techniques, these findings highlight that crossed screw fixation remains an important and economical option, warranting further prospective comparative studies.

Staples and compression staples have also been increasingly utilized for first MTP arthrodesis, with biomechanical and early clinical studies suggesting that they can provide sufficient fixation strength and favorable union rates. For example, Schafer et al²³ demonstrated the biomechanical performance of nitinol staples in cadaveric models of first MTP arthrodesis. Additionally, Romere et al²⁴ compared memory compression staples, cannulated screws, and dorsal plating, reporting that staples may outperform some constructs in certain parameters. From a cost perspective, staples may offer an economical option in certain healthcare settings. However, their availability remains limited in the region, which precluded their inclusion in the study cohort. Nonetheless, their potential role should be acknowledged, and future comparative studies involving staples, screws, and plate constructs would be valuable to guide implant selection.

Strengths and limitations

This study possesses several notable strengths. First, it is the first comprehensive analysis directly comparing clinical outcomes and total treatment costs across 3 common fixation strategies—isolated DLP, DLP with a single lag screw, and DLP with dual lag screws—for the first MTP arthrodesis. By combining robust clinical outcomes such as radiographic union rates, revision surgery rates, and functional scores with a thorough cost analysis over a standardized 12-month follow-up, the current study addresses a critical gap in the literature regarding value-based decision-making in foot surgery. Another significant strength lies in the methodological consistency of the surgical procedures and postoperative protocols, all conducted by a single experienced surgical team, which effectively minimizes procedural variability.

Nevertheless, there should be an admission of certain shortcomings. Primarily, the retrospective design is susceptible to selection bias and data collection inaccuracies due to the pre-recorded clinical data. Moreover, the relatively small sample size corresponding to each group might limit the generalization of results, especially in fine analysis regarding differences between single and double lag screw configurations. Furthermore, all procedures were performed by a single experienced surgical team, which ensured methodological consistency and minimized variability, but at the same time may limit generalizability to different clinical environments and carries the potential for bias toward the team’s preferred techniques. Another limitation is that effect size measures were not reported for the significant findings. While statistical significance was demonstrated, the absence of effect size reporting may limit the ability to fully gauge the magnitude and clinical relevance of the observed differences. Another limitation is that a priori power analysis was not conducted, and the study sample was based solely on the available patient population meeting the eligibility criteria. Indirect costs like loss of productivity, transportation of patients, or carer burden were also not factored into the economic analysis, thereby potentially underestimating the broader economic impact from a societal perspective. In addition, despite a 1-year follow-up yielding worthwhile information about the immediate costs and outcomes after operations, it is necessary to conduct cost and outcome analysis in the future to establish the long-term sustainability. Gender distribution differed significantly among groups, which may have introduced bias; however, subgroup analysis was not feasible due to the limited sample size. Moreover, although costs were converted into USD using year-adjusted exchange rates to enhance international comparability, residual effects of currency fluctuation and local inflation cannot be entirely excluded. Finally, another limitation of this study is the absence of a crossed screw fixation group, which precluded direct comparison with this widely used and potentially more economical technique.

This study reveals that the addition of a single lag screw to DLP fixation for the first MTP joint arthrodesis in advanced HR provided better clinical results and also afforded the best cost-effectiveness profile at 1-year follow-up. While isolated DLP initially may appear more cost-effective, greater revision surgery rates and longer times to union contribute to much greater cumulative costs. Conversely, dual lag screw augmentation does not provide additional clinical benefits despite increased implant expenses. Hence, the combination of a single lag screw with a DLP emerges as an ideal mode of fixation, balancing the cost of the implant and effectiveness with complication rates, which may be considered a preferred fixation strategy in clinical practice. More prospective studies with larger sample sizes and longer follow-up periods will help to confirm these results and strengthen the evidence-based recommendations in clinical practice.

Funding Statement

The authors declared that this study has received no financial support.

Data Availability Statement:

The data that support the findings of this study are available on request from the corresponding author.