Radiological Parameters for Predicting the Risk of Flexor Tendon Rupture after Volar Plate Fixation for Distal Radius Fracture

Abstract

Background

In this study, we aimed to investigate postoperative radiographic parameters for predicting flexor tendon rupture after volar plate fixation for distal radius fractures.

Methods

In this retrospective cohort study, postoperative radiographs of 15 cases of flexor tendon rupture were included as a flexor tendon rupture group. Additionally, data from 45 patients with non-flexor tendon rupture (control group), matched in terms of age, sex, and fracture type (1 : 3) to the flexor tendon rupture group, were reviewed in terms of fracture reduction and plate position. We assessed the Soong grade, plate-to-critical line distance (PCLD), and plate-to-volar rim distance to determine plate position and used other parameters to analyze anatomical reduction including radial tilt, ulnar variance, coronal carpal translation, radius-radial styloid distance, volar tilt, sagittal carpal alignment (SCA), and radius-volar lip distance (RVLD).

Results

We identified 3 significant predictive factors for flexor tendon rupture after volar plate fixation for distal radius fractures. The mean PCLD and SCA were significantly greater in the flexor tendon rupture group than in the control group (p < 0.001). The mean RVLD was smaller in the flexor tendon rupture group than in the control group (p = 0.033). Logistic regression analysis was performed to examine the importance of the variables.

Conclusions

Our findings underscore the importance of PCLD, SCA, and RVLD as significant risk factors for flexor tendon rupture. Accurate plate positioning, achieving appropriate anatomical reduction, and vigilant monitoring for signs of plate irritation in high-risk patients may help prevent flexor tendon rupture.

Distal radius fractures are one of the most common upper-extremity injuries, accounting for approximately 18% of all adult orthopedic fractures in the United States.¹⁾ Over the past 2 decades, treatment strategies have evolved from percutaneous pinning or external fixation to open reduction and internal fixation using a volar locking plate (VLP), which provides for a lower profile and anatomically contoured fixation to reduce the risk of implant-associated complications.²,³⁾ However, despite the increased use of VLPs, the rate of relevant complications, such as tendon rupture, hardware failure, infection, malunion, and arthritis, remains high at 3%–27%.¹,⁴,⁵⁾ Flexor tendon rupture, an uncommon but serious complication, often takes a long time to be diagnosed after fixation because it manifests as pain and loss of function.⁶,⁷⁾ In particular, the flexor pollicis longus (FPL) is most susceptible to rupture, followed by the index flexor digitorum profundus.⁸⁾

Tendon rupture is primarily attributed to tendon attrition, and its pathogenesis is multifactorial. Reported risk factors for tendon rupture include suboptimal plate positioning (excessive distal positioning or volar protrusion of the distal end of the plate), inadequate fracture reduction, progressive loss of reduction, and improper technique (prominent screw heads or incorrect plate usage).⁷,⁹,¹⁰,¹¹,¹²⁾ Soong et al.⁹,¹²⁾ developed a grading system to assess volar plate prominence and its association with tendon rupture; however, their findings were constrained by a small sample size, and subsequent studies have reported inconsistent results.¹³,¹⁴⁾

We hypothesized that while plate prominence is a critical risk factor, achieving anatomical reduction and considering associated radiographic parameters are equally important in reducing the risk of flexor tendon rupture following VLP fixation. This study aimed to investigate the role of plate prominence as a risk factor and to identify radiographic parameters indicative of anatomical reduction. These findings were intended to guide surgeons in optimizing surgical techniques and postoperative management, including fracture reduction, plate positioning, and the potential for preemptive plate removal in high-risk cases.

METHODS

This case-control study obtained Institutional Review Board approval from The Catholic University of Korea (IRB No. VC24RIDI0121, June 2024). The requirement for informed consent was waived due to the retrospective nature of the study.

Patients

We reviewed the medical records of patients who underwent VLP fixation for distal radius fractures at 2 hospitals between January 2010 and December 2020. Fifteen patients treated for complete flexor tendon rupture after VLP fixation for distal radius fracture were included in this study. Their demographic information is presented in Table 1.

Table 1. Demographics of Patients with Flexor Tendon Ruptures.

Case	Age (yr)	Sex	Side	Tendon rupture	Soong grade	Time from surgery (mo)	Fracture classification	Plate type
1	77	F	Rt	FPL	I	32	A	Acumed Acu-Loc
2	73	F	Rt	FPL	I	72	A	Acumed Acu-Loc
3	81	M	Rt	FPL	I	10	C	Synthes 2.4 VA-LCP
4	65	F	Lt	Index finger FDP	I	20	A	Synthes 2.4 VA-LCP
5	68	F	Rt	Index finger FDP	I	17	C	Synthes 2.4 VA-LCP
6	32	M	Lt	Index finger FDP	I	27	C	Synthes LCP
7	60	F	Rt	FPL, index finger FDP	I	13	C	Other
8	56	M	Lt	Index finger FDP	I	5	C	Acumed Acu-Loc
9	80	M	Rt	Index finger FDP	I	9	C	Synthes 2.4 VA-LCP
10	73	F	Rt	Index finger FDP	I	6	C	Acumed Acu-Loc
11	68	F	Rt	FPL	I	84	C	Other
12	64	F	Lt	FPL	II	60	B	Acumed Acu-Loc
13	53	F	Rt	FPL	I	55	C	Other
14	75	F	Rt	Index finger FDP	I	54	C	Synthes 2.4 VA-LCP
15	63	F	Lt	FPL	I	6	C	ARIX 2.5 plate

Rt: right, Lt: left, FPL: flexor pollicis longus, FDP: flexor digitorum profundus.

The control population comprised patients without tendon injury or rupture complications for at least 3 years after VLP fixation who were age-, sex-, and fracture type-matched (1 : 3) to those with flexor tendon rupture using propensity score matching (PSM). We performed PSM to control for potential confounding variables and ensure comparability between the flexor tendon rupture group and control group. The propensity scores were calculated using a logistic regression model that included age, sex, and fracture type as covariates. Each patient in the flexor tendon rupture group was matched to 3 patients in the control group (1 : 3 matching) to enhance statistical power. The matching algorithm used the greedy, nearest-neighbor method without replacement and applied a caliper width of 0.01 of the propensity score. Statistical analysis confirmed no significant differences in age, sex, or fracture type between the groups after matching.

Radiographic Evaluation

Posteroanterior (PA) and lateral follow-up radiographs were obtained for both flexor tendon rupture cases and controls. Radiographs were obtained at the first hospital visit for the rupture group and during the last follow-up visit for the control group. Standardized acquisition timing was not possible owing to the retrospective design and variability in rupture timing. Three independent observers (all senior professors from the department of orthopedic surgery and fellowship-trained hand surgeons [SHK, IJP and HWP]), blinded to any patient-identifying information, reviewed all radiographs. To ensure consistency, the observers participated in a pre-study meeting to standardize measurement methodology and independently obtained specific parameters from the images. Measurement reliability, assessed using the intraclass correlation coefficient (ICC), showed near-perfect agreement among observers (Table 2).

Table 2. The Level of Agreement in the Measured Variables.

Risk factor	ICC	95% CI
PCLD (mm)	0.984	0.976–0.990
PVRD (mm)	0.975	0.961–0.984
Volar tilt (°)	0.961	0.941–0.976
Radial tilt (°)	0.992	0.988–0.995
Ulnar variance (mm)	0.992	0.987–0.995
Coronal carpal translation (mm)	0.994	0.990–0.996
Sagittal carpal alignment (mm)	0.918	0.874–0.948
Radius-radial styloid distance (mm)	0.977	0.965–0.986
Radius-volar lip distance (mm)	0.959	0.937–0.974

ICC: intraclass correlation coefficient, PCLD: plate-to-critical line distance, PVRD: plate-to-volar rim distance.

In the present study, we applied the Soong grading system to each patient, following the methodology outlined by Soong et al.⁹⁾ to evaluate plate position. To further refine our assessment of plate location, we introduced 2 additional parameters: distance between the plate and volar critical line (plate-to-critical line distance [PCLD]) and the distal plate position, determined by measuring the distance between the most distal extension of the plate and the most distal portion of the volar rim (the plate-to-volar rim distance [PVRD]) on a standard lateral wrist plain radiograph.¹⁰⁾ The volar critical line was defined as a line parallel to the volar cortical axis of the radius on a lateral wrist radiograph, extending to the most volar point of the distal radius. This reference line serves as a standard for measuring parameters, such as PCLD and PVRD, which are used to evaluate plate prominence and its association with flexor tendon rupture (Fig. 1). In addition, we used other parameters, including radial tilt, ulnar variance, coronal carpal translation, radius-radial styloid distance measured from PA radiographs, volar tilt, sagittal carpal alignment (SCA), and radius-volar lip distance (RVLD) measured from lateral radiographs (Fig. 2). On PA radiographs, coronal carpal translation was measured as the shortest distance between the proximal capitate center and ulnar shaft centerline. Radius-radial styloid distance was the distance between the radius centerline and a parallel line passing through the radial styloid tip. On the lateral radiograph, the SCA was indicated as the shortest distance between the extension of the anterior cortical bone of the radius and the center of the proximal capitate, representing the alignment of the carpal bones and its biomechanical significance. RVLD was indicated as the distance between the volar cortex line of the radius and volar critical line, reflecting anatomical reduction and its potential impact on flexor tendon proximity.

Fig. 1. Parameters assessed for plate position and prominence. 1: Plate to volar rim distance (mm) was defined as the distance between the volar rim line and the distal edge of the plate, 2: Plate to volar critical line distance (mm) was defined as the distance between the volar critical line and the most volar point of the plate. Lines A: volar cortex line of the radius, B: volar critical line, defined as a line parallel to the volar cortex line of the radius, passing through the most volar point of the distal radius, C: volar rim line, defined as a line perpendicular to the volar cortex line of the radius passing through the most distal point of the distal radius volar rim.

Fig. 2. (A, B) Parameters assessed for fracture reduction on posteroanterior and lateral radiographs of the wrist. 1: Radial tilt (°), 2: Ulnar variance (mm), 3: Coronal carpal translation (mm), 4: Radius-radial styloid distance (mm), 5: Volar tilt (°), 6: Sagittal carpal alignment (mm), defined as the shortest distance between the radius volar cortex line and the center of the capitate, reflecting alignment in the sagittal plane, 7: Radius-volar lip distance (mm), defined as the distance between the volar cortex line of the radius and the volar critical line, indicating anatomical reduction and proximity to flexor tendons. Lines A: a line parallel to a center line of the radius passing through the tip of the radial styloid process, B: a center line of the radius, C: a center line of the ulna, D: volar critical line, E: volar cortex line of the radius.

Statistical Analysis

Intraobserver agreement was assessed using the ICC and its 95% CI. Data are presented as mean ± standard deviation, and mean differences between the flexor tendon rupture and control groups were determined using a 2-sample t-test or Smith-Satterthwaite’s test, depending on whether the homogeneity of variances was met. The Fisher’s exact test was performed to compare Soong grade between the 2 groups. Univariate logistic regression analysis of each variable was performed, and the results are presented as odds ratios (ORs) and their 95% CIs. Binary logistic regression was used for the Soong grade. Multivariate regression analysis was not possible owing to the small sample size. To enhance the robustness of our findings and address the limitations of a small sample size, we performed additional sensitivity analyses. Logistic calibration curves were generated, and mean absolute errors were calculated using the bootstrap resampling method (1,000 repetitions) to validate the stability of the identified predictors. Statistically significant results were plotted graphically. Statistical significance was set at a p-value of ≤ 0.05 (2-tailed). All statistical analyses were performed using SAS (version 9.4; SAS Institute Inc.).

RESULTS

Reproducibility was assessed using ICC, demonstrating near-perfect inter-rater reliability among the 3 independent observers (Table 2). The likelihood of having a higher Soong grade was greater in the flexor tendon rupture group than in the control group (p = 0.031, Fisher’s exact test). In the comparison between groups with grades 0 and 1 and those with grades 0 and 2 in binary logistic regression, large ORs were observed for the groups with grades 1 and 2; however, owing to the small number of patients, these findings were not considered statistically significant (Table 3). Quantitative analysis revealed that the PCLD was significantly associated with flexor tendon rupture. Specifically, the mean PCLD was markedly greater in the flexor tendon rupture group than in the control group (3.54 ± 1.46 mm vs. 1.20 ± 1.57 mm, p < 0.001). Although the mean PVRD was shorter in the rupture group (2.58 ± 1.78 mm) than in the control group (3.31 ± 1.76 mm), this difference was not statistically significant (p = 0.173) (Fig. 3, Table 4). SCA and RVLD on lateral radiographs significantly differed between the groups. The mean SCA was greater in the rupture group than in the control group (5.26 ± 2.48 mm vs. 2.52 ± 2.45 mm, p < 0.001). Conversely, the mean RVLD was significantly shorter in the flexor tendon rupture group than in the control group (7.50 ± 1.97 mm vs. 8.63 ± 1.64 mm, p = 0.033) (Fig. 4, Table 4).

Table 3. Soong Grades of Patients with Tendon Ruptures Versus Controls.

	Soong grade			p-value
	0	1	2
Rupture	0	14 (93.3)	1 (6.7)	0.039
Control	12 (26.7)	32 (71.1)	1 (2.2)	Reference

Values are presented as number (%). Although tendon rupture patients tended to have higher Soong grades than controls, logistic regression did not reach statistical significance due to the small sample size.

Fig. 3. Plate position measurements. The scatter plot shows the plate-to-critical line distance (PCLD) and plate-to-volar rim distance (PVRD) for each group. The flexor tendon rupture group shows greater PCLD and lower PVRD.

Table 4. Mean Values of the Explanatory Variables, Stratified According to Cases (Tendon Rupture) and Controls (No Tendon Rupture).

Variable	Flexor tendon rupture	Control	p-value
PCLD (mm)	3.54 ± 1.46	1.20 ± 1.57	< 0.001
PVRD (mm)	2.58 ± 1.78	3.31 ± 1.76	0.172
Volar tilt (°)	6.87 ± 7.70	9.42 ± 5.15	0.246
Radial tilt (°)	22.62 ± 3.95	23.43 ± 3.76	0.475
Ulnar variance (mm)	2.45 ± 2.82	2.60 ± 1.67	0.266
Coronal carpal translation (mm)	20.23 ± 4.27	20.78 ± 2.51	0.848
Sagittal carpal alignment (mm)	5.26 ± 2.48	2.52 ± 2.45	< 0.001
Radius-radial styloid distance (mm)	13.06 ± 2.21	12.74 ± 1.91	0.596
Radius-volar lip distance (mm)	7.50 ± 1.97	8.63 ± 1.64	0.033

Values are presented as mean ± standard deviation.

PCLD: plate-to-critical line distance, PVRD: plate-to-volar rim distance.

Fig. 4. Fracture reduction measurements. The scatter plot shows that sagittal carpal alignment (SCA) and radius-volar lip distance (RVLD) are associated with flexor tendon rupture. The flexor tendon rupture group shows greater SCA and lower RVLD.

In this study, various types of VLPs were used. In the control group, Acu-Loc plates (18 cases) and Synthes plates (19 cases) were the most commonly used, while in the flexor tendon rupture group, Acu-Loc plates (5 cases) and Synthes plates (6 cases) were predominant. However, no significant association was observed between the plate type and flexor tendon rupture. PSM was performed to balance the groups for age, sex, and fracture type (AO classification); However, no significant differences in age, sex, or fracture type were observed between the groups (p > 0.05 for all variables).

Univariate logistic regression analysis revealed a 3.9-fold increase in the risk of flexor tendon rupture for every 1-mm increase in PCLD (OR, 3.91; 95% CI, 1.750–8.735; p = 0.001). In addition, for every 1-mm increase in SCA and RVLD, the risk of tendon rupture increased by 1.56-fold (OR, 1.558; 95% CI, 1.170–2.074; p = 0.002) and 0.68-fold (OR, 0.681; 95% CI, 0.471–0.983; p = 0.041), respectively. OR for PCLD, SCA, and RVLD indicate their association with the risk of flexor tendon rupture (Fig. 5, Table 5).

Fig. 5. The graph shows the correlation between the significant parameters and the risk of flexor tendon rupture. The risk of tendon rupture increases from approximately 15% to 75% when plate-to-critical line distance (PCLD; A) increases from 2 mm to 4 mm and from approximately 30% to 80% when the sagittal carpal alignment (SCA; B) increases from 5 mm to 10 mm. The risk decreases from 25% to approximately 8% when radius-volar lip distance (RVLD; C) increases from 8 mm to 12 mm.

Table 5. Univariable Logistic Regression Analysis of Measurements.

Risk factor	Odds ratio (95% CI)	p-value
PCLD	3.910 (1.750–8.735)	0.001
PVRD	0.778 (0.542–1.117)	0.173
Volar tilt	0.927 (0.836–1.028)	0.152
Radial tilt	0.942 (0.801–1.107)	0.469
Ulnar variance	0.962 (0.714–1.297)	0.800
Coronal carpal translation	0.941 (0.776–1.141)	0.538
Sagittal carpal alignment	1.558 (1.170–2.074)	0.002
Radius-radial styloid distance	1.084 (0.808–1.455)	0.600
Radius-volar lip distance	0.681 (0.471–0.983)	0.041

PCLD: plate-to-critical line distance, PVRD: plate-to-volar rim distance.

DISCUSSION

The cause of flexor tendon rupture after VLP fixation is considered multifactorial. Its known risk factors such as poor plate position, fracture malreduction, and improper surgical technique eventually lead to persistent irritation of the flexor tendon, resulting in attritional rupture.⁹,¹⁰,¹¹,¹²,¹⁵,¹⁶⁾ In the present study, we investigated significant potential radiological parameters to predict the risk of flexor tendon rupture after VLP fixation for distal radius fracture based on postoperative radiographs. In addition to plate malposition, we highlighted inadequate anatomic reduction of the fracture as a crucial factor associated with flexor tendon rupture. To assess plate positioning, we used Soong’s grading system along with quantitative measurements of PCLD and PVRD. For evaluation of anatomic reduction, we analyzed several parameters including volar tilt, radial tilt, ulnar variance, coronal carpal translation, SCA, radius-radial styloid distance, and RVLD.

Soong et al.⁹⁾ designed a classification system to determine volar plate prominence and reported that plate position is a risk factor for flexor tendon rupture; however, the study’s conclusions were limited by the small sample size of the study (only 3 cases of flexor tendon ruptures). The impact of Soong’s research has led to many subsequent studies supporting his theory. Agnew et al.¹⁷⁾ reported that when the plate was placed 3 mm proximally to the watershed line, a very high probability of direct contact with the flexor tendon was observed on magnetic resonance imaging. In addition, Kitay et al.¹⁰⁾ reported an increased risk of flexor tendon rupture when the plate prominence was > 2.0 mm volar to the critical line or when the plate position was within 3.0 mm of the volar rim. As reported in various studies, PCLD and PVRD have been proposed as significant parameters reflecting the appropriateness of plate position (plate volar prominence or overriding the watershed line), which can contribute to flexor tendon rupture. These metrics are critical in evaluating plate placement and its potential biomechanical impact on tendon integrity. By integrating these established parameters into our study, we aimed to build upon prior evidence and emphasize their clinical importance. In the present study, the likelihood of having a higher Soong grade was greater in the flexor tendon rupture group than in the control group (p = 0.031). Quantitative measurement of PCLD was associated with flexor tendon injury (p < 0.001). The mean PVRD was shorter in the rupture group than in the control group (2.58 ± 1.78 mm vs. 3.31 ± 1.76 mm); however, the difference was not significant (p = 0.173). In contrast, Snoddy et al.¹⁴⁾ suggested that the protrusion of the plate was not the main factor in flexor tendon rupture and that other risk factors should be investigated.

Insufficient reduction or reduction loss of the fracture has been associated with flexor tendon rupture in some studies. According to Orbay and Touhami,¹⁸⁾ the loss of fracture reduction can lead to flexor tendon complications. Stepan et al.¹⁹⁾ and Wurtzel et al.²⁰⁾ argued that loss of volar tilt has a significant impact on the risk of flexor tendon contact with the fixed plate and is associated with the occurrence of flexor tendon rupture. Notably, Selvan et al.²¹⁾ highlighted the importance of radial inclination and reported that FPL rupture worsens when the radial tilt is < 25°. Lv et al.²²⁾ reported that decreasing volar tilt results in more lateral plate protrusion than decreasing radial tilt, which increases plate contact with the FPL and thus worsens the rupture. Kwon et al.²³⁾ suggested that volar tilt, carpal translation, and teardrop angle are critical risk factors for flexor tendon rupture and that inappropriate reduction of the fracture adversely affects the flexor tendon contact with the volar plate. In our study, volar tilt differed between the flexor tendon rupture (6.87 ± 7.70) and control (9.42 ± 5.15) groups; however, no significant difference in the incidence of flexor tendon rupture was observed between the groups (p = 0.246). This factor may still be important, but the small sample size of the present study did not allow us to perform multivariable logistic regression to assess the interaction between variables. However, it is noteworthy that dorsal tilting was observed in 4 cases (–2.7°, –5.8°, –3.6°, and –5.5°) within the flexor tendon rupture group, reflecting potential malreduction. Previous studies have suggested that dorsal tilting increases plate prominence, potentially elevating the risk of flexor tendon rupture.²¹,²³⁾ Although not statistically significant, the flexor tendon rupture group in this study exhibited a greater tendency toward dorsal tilting than did the control group, underscoring the importance of achieving proper anatomical reduction during surgery to minimize dorsal tilt and its associated risks. SCA and RVLD on lateral radiographs were significantly associated with the occurrence of flexor tendon rupture. The rupture group exhibited a significantly greater mean SCA (5.26 ± 2.48 mm vs. 2.52 ± 2.45 mm in controls, p < 0.001) and shorter mean RVLD (7.50 ± 1.97 mm vs. 8.63 ±1.64 mm in controls, p = 0.033). In this study, SCA was significantly associated with flexor tendon rupture, suggesting its importance in clinical outcomes, which is consistent with the findings from a previous study.²³⁾ We believe that proper SCA plays a critical role in maintaining normal wrist kinematics and minimizing the risk of complications, such as flexor tendon rupture due to plate prominence. During surgery, efforts should focus on achieving SCA by aligning the radius-volar cortex line with the center of the capitate head as a target point for reduction.²⁴⁾ Although achieving perfect SCA intraoperatively can be challenging, careful attention to SCA during fracture reduction is likely to be an essential aspect of surgical planning.²⁵⁾ Our study introduces RVLD as a novel parameter to assess anatomical reduction and its association with flexor tendon rupture. This parameter reflects sagittal plane alignment, with smaller values potentially indicating inadequate reduction (e.g., dorsal tilting or displacement). Reduced RVLD values may increase the risk of flexor tendon rupture by narrowing the distance between the volar plate and flexor tendons. These findings underscore RVLD’s importance in evaluating reduction quality and its clinical implications. In our study, PCLD, SCA, and RVLD were identified as significant parameters associated with flexor tendon rupture. These findings emphasize the critical role of precise plate positioning and anatomical reduction in surgical planning and patient management, underscoring the need for further research to refine techniques and enhance clinical outcomes. In the present study, all significant risk factors for flexor tendon rupture were measured on lateral radiographs. Therefore, to achieve an actual lateral wrist view, the palmar cortex of the pisiform should be centrally located between the volar cortices of the capitate and scaphoid.²⁶⁾

We acknowledge several limitations of our study. Its retrospective design and reliance on medical records for demographic information introduce potential bias. One limitation of our study is the variation in the timing of radiograph acquisition between the flexor tendon rupture and control groups. This discrepancy in timing could have introduced variability in the measurements. Future studies with standardized radiograph acquisition protocols could mitigate this limitation. In addition, the rarity of flexor tendon rupture after VLP fixation resulted in a relatively small sample size, precluding the use of more comprehensive statistical analyses such as multivariable logistic regression. Despite using 6 different plate types in our study, we were unable to establish meaningful correlations between specific plate designs and the risk of flexor tendon rupture owing to the limited sample size. It is possible that other examined variables may also be significant, but our current data set does not allow definitive conclusions to be drawn. Future research with larger cohorts and prospective designs would be valuable in further elucidating the complex interplay of factors that contribute to flexor tendon rupture following VLP fixation for distal radius fractures. Such studies could potentially identify additional risk factors and help refine surgical techniques to minimize this serious complication. Although our findings provide clinically significant insights, the interpretation of results should account for the small sample size and retrospective study design, which may affect the broader applicability of our conclusions. Further research is necessary to validate the predictive value of parameters, such as PCLD, SCA, and RVLD, and to enhance surgical strategies aimed at reducing flexor tendon rupture risk after VLP fixation.

In conclusion, our findings underscore the importance of accurate anatomic reduction and optimal plate positioning to alleviate the incidence of flexor tendon rupture after VLP fixation for distal radius fracture. We found that minimizing volar prominence of the plate, maintaining an appropriate RVLD, and aligning the SCA with the radius-volar cortical line are critical factors in reducing the risk of flexor tendon rupture. Postoperative radiographs, particularly lateral views, should be obtained with the patient in an accurate position. For high-risk patients, vigilant monitoring for plate irritation signs and considering preemptive plate removal, if necessary, may help avoid serious postoperative complications such as tendon rupture. We believe that the translation of these findings into clinical practice could significantly improve outcomes of volar locking plating for distal radius fractures.