Fingertip and pulp defects are among the most frequently encountered injuries in hand surgery, often resulting from trauma, workplace accidents, or thermal injuries [1-3]. The fingertip serves not only as an aesthetic focal point but also as a critical component of hand function, responsible for fine motor skills, sensation, and dexterity [4,5]. Thus, the challenge in managing such injuries lies not only in covering the defect but also in restoring the intricate sensory feedback and functional capabilities that the fingertip provides [2,6]. Improper or suboptimal reconstruction can lead to long-term functional deficits, sensory disturbances, or poor cosmetic outcomes, significantly affecting a patient’s quality of life.

Over the years, a variety of surgical techniques have been developed for the reconstruction of fingertip and pulp defects [7-9]. Historically, the thenar flap has been a widely utilized method due to its reliability, simplicity, and well-established vascular supply [7,9,10]. However, despite its effectiveness in covering small to moderate defects, it is associated with notable drawbacks. The 2-week period of immobilization, during which the flap is attached to the palm, can cause significant discomfort for patients, limit hand function, and delay recovery. Additionally, the aesthetic bulk of the flap and the potential for incomplete sensory recovery have led to a search for alternative solutions.

As surgical techniques have advanced, the partial toe pulp free flap was developed to provide a more refined option for fingertip reconstruction [3,11,12]. This technique offers the advantage of near-anatomical restoration, allowing for the transfer of neurovascularly intact tissue that closely mimics the structure and function of the original fingertip. The partial toe pulp flap, with its superior sensory recovery and excellent aesthetic outcomes, quickly gained popularity in cases where precise reconstruction of both function and appearance was critical. However, this method requires microsurgical expertise and involves potential donor site morbidity, which may limit its use in some settings.

More recently, the radial artery superficial palmar (RASP) flap has emerged as another valuable option for fingertip and pulp defect reconstruction [13-16]. The RASP flap provides neurovascularly based coverage with thinner tissue, offering better sensory recovery and cosmetic results for medium to large defects. It eliminates the prolonged hand immobilization seen with the thenar flap and preserves donor site function, making it a versatile solution for cases requiring larger tissue coverage.

The choice between these methods is often dictated by the size of the tissue defect, along with patient-specific factors such as occupation, lifestyle, and expectations for recovery. Smaller defects may still be well-suited to the simplicity of the thenar flap, while medium and larger defects benefit from the precision of microsurgical techniques like the partial toe pulp flap or RASP. This paper aims to analyze the application of these three reconstructive methods—thenar flap, partial toe pulp free flap, and RASP—in relation to defect size, providing a comprehensive guide for selecting the most appropriate technique. By exploring the strengths, limitations, and outcomes associated with each method, this study seeks to offer surgeons a practical framework to improve decision-making and optimize patient outcomes.

This study is a retrospective chart review of patients who underwent fingertip and pulp reconstruction using one of three techniques: the thenar flap, partial toe pulp free flap, or RASP flap. The surgeries were performed by a single surgeon between March 2023 and November 2024. Data were collected from medical records, operative reports, and postoperative follow-up notes to evaluate surgical outcomes and patient satisfaction. Patients included in the study presented with fingertip or pulp defects caused by trauma, burns, or workplace injuries, and no exclusions were made for systemic diseases such as hypertension, diabetes, or cardiovascular conditions.

For each patient, detailed demographic and clinical data were recorded, including sex, age, the side and digit of the injured finger, past medical history, and smoking status. The size of each defect was measured intraoperatively using a paper ruler and recorded in centimeters (width×height). The method of anesthesia used during surgery—whether brachial plexus block (BPB), general anesthesia, or local anesthesia—was documented.

The primary outcome measures included flap survival, donor site morbidity, and patient self-reported satisfaction. Flap survival was defined as complete survival without necrosis or the need for additional surgical intervention. Donor site morbidity was assessed based on complications such as hypertrophic scarring, pain, and joint stiffness. Patient satisfaction was evaluated through follow-up interviews or questionnaires and categorized into three levels: “very satisfied,” “somewhat satisfied,” and “unsatisfied.”

A total of 50 cases were included in the study, with nine cases in the thenar flap group, 26 in the partial toe pulp free flap group, and 15 in the RASP flap group. Descriptive statistics were used to summarize patient demographics, defect sizes, success rates, and complications. Age and defect size were analyzed using analysis of variance, and categorical variables such as smoking status, the presence of side effects, and previous medical history were analyzed using the Fisher exact test and chi-square test. Statistical data analysis was performed using IBM SPSS Statistics ver. 29 (IBM Corp., Armonk, NY, USA), and a p-value of <0.05 was considered statistically significant.

A total of 50 patients underwent fingertip and pulp reconstruction using one of three techniques: the thenar flap (n = 9), partial toe pulp free flap (n = 26), and RASP flap (n = 15). In the thenar flap group, there were eight males and one female, with an average age of 38.7 years (range, 1–62 years) and an average defect size of 1.5×1.1 cm. All flaps survived without necrosis. Donor site morbidity included two cases of thenar area pain, one case of joint stiffness, and one case of both thenar area pain and joint stiffness. Patient satisfaction was rated as “very satisfied” in five cases and “somewhat satisfied” in four cases (Table 1).

In the partial toe pulp free flap group, there were 24 males and two females, with an average age of 52.2 years (range, 26–72 years) and an average defect size of 2.87×1.5 cm. All flaps survived, with one case of partial necrosis. No donor site morbidity was reported. Patient satisfaction was uniformly high, with all 26 patients reporting being “very satisfied” (Table 2).

The RASP flap group included 15 males, with an average age of 48.5 years (range, 28–74 years) and an average defect size of 5.4×2.5 cm. All flaps survived, but partial necrosis was observed in three cases. Donor site morbidity included five cases of hypertrophic scarring. Patient satisfaction was reported as “very satisfied” in 12 cases, “somewhat satisfied” in two cases, and “unsatisfied” in one case. RASP can be performed as a regional block using BPB, but due to a patient’s panic disorder, the BPB failed, and the surgery was performed under general anesthesia (Table 3).

Data regarding smoking status and systemic comorbidities, such as hypertension and diabetes, were also collected. However, due to the small sample sizes within each group and the high overall survival rates, statistical analyses to assess correlations between these factors and flap survival were not performed, as the results would be statistically inconclusive. These limitations are acknowledged when interpreting the findings. In the comparison among the three groups, there were no significant differences in variables except for size (p>0.05). Determining the surgical method based on the size of the soft tissue defect yielded significant results (Table 4).

This study compared the outcomes of three reconstructive techniques for fingertip and pulp defects: the thenar flap, partial toe pulp free flap, and RASP flap. The findings demonstrated that all three methods are highly effective for flap survival, but each presents unique strengths and limitations that must guide surgical decision-making.

The thenar flap remains a reliable option for small fingertip defects, especially those with exposed bone [9,10,17]. Its simplicity and relatively short surgical time make it an excellent choice for surgeons with limited microsurgical experience. Additionally, as demonstrated in case number 7, this surgery can be performed on a 1-year-old child. In pediatric patients, thenar flaps are preferred because free flaps are challenging due to the small size of the blood vessels and the significant burden associated with failure. However, complications such as donor site pain and joint stiffness are common, particularly in older patients. The mandatory 2-week attachment to the palm can also cause discomfort and limit hand mobility. Despite these drawbacks, the thenar flap is a practical option for smaller defects, particularly in patients without significant comorbidities.

The partial toe pulp free flap is especially suited for moderate-sized defects where both cosmetic and functional restoration are critical. By transferring neurovascularly intact tissue, it offers superior sensory and aesthetic outcomes. However, this technique demands a high level of surgical expertise and involves anesthetizing both the arm and leg, which may complicate postoperative recovery. Nevertheless, ultrasound-guided popliteal nerve block is easy and convenient. It is safer than general anesthesia and spinal anesthesia, and therefore partial toe pulp free flap are mainly performed using BPB and popliteal nerve block [18].

In this study, aside from two cases of general anesthesia and one case of BPB with spinal anesthesia, BPB with Popliteal nerve block was administered in 23 cases. Additionally, in two cases, general anesthesia was required because BPB with Popliteal nerve block was not possible due to the patients’ panic disorder. Based on our findings, the defect size for partial toe pulp free flap reconstruction should ideally not exceed 3.5 cm in length and 1.5 cm in width, as larger defects make donor site closure challenging and increase the risk of complications such as tension-related wound dehiscence. The natural elasticity and resilience of toe skin make it a viable option for moderate defects, filling a critical gap between small defects best managed with the thenar flap and large defects requiring alternative approaches.

The RASP flap is the preferred choice for larger defects, offering excellent aesthetic results due to its use of tissue similar to the palm [16,19]. While the length of the flap can be extended to accommodate larger defects, the width should ideally remain below 2.5 cm to avoid excessive tension during donor site closure. This tension likely contributes to the hypertrophic scarring observed in five cases in our study. Additionally, the structural differences between palm and toe skin—such as thickness, vascularity, and tension distribution—may explain the increased risk of scarring in the palm. For larger defects where functional and aesthetic restoration is critical, the RASP flap remains a strong option, provided that donor site tension is minimized during closure [20].

Postoperative management also played a crucial role in recovery outcomes. For the thenar flap, no initial splinting was required, and the flap was secured with taping during the 2-week attachment period. After division, a finger splint was used for one week, followed by immediate initiation of physical therapy to restore ROM and prevent stiffness. In contrast, the partial toe pulp free flap required a short arm splint for one week, with either a finger splint or simple dressing used subsequently depending on the presence of a metal core. Physical therapy began 3 weeks postsurgery to ensure flap stability before mobilization. The RASP flap, due to the donor site closure on the palm, required a short arm splint for 2 weeks. Therapy initiation was delayed until 3 weeks postsurgery to allow for proper healing of both the flap and donor site. These tailored postoperative protocols highlight the importance of balancing flap protection and early mobilization to achieve optimal outcomes.

It is noteworthy that all three techniques showed high survival rates, with the thenar flap and partial toe pulp free flap achieving 100% survival. In the RASP flap group, all flaps survived as well, though three cases experienced partial necrosis. These findings emphasize the importance of meticulous surgical technique, particularly in managing larger defects where flap design and donor site tension play crucial roles.

Patient selection is a critical factor in determining the success of fingertip reconstruction. The thenar flap is ideal for small defects, but its use in larger defects is less favorable due to joint stiffness and donor site morbidity. The partial toe pulp free flap excels in moderate defects, combining superior sensory recovery and aesthetics, though it requires significant technical expertise. The RASP flap is invaluable for larger defects but demands careful donor site management to reduce complications such as hypertrophic scarring.

This study has limitations, including a relatively small sample size and a lack of long-term follow-up, which limit the statistical power and generalizability of the findings. Future research with larger cohorts and extended follow-up is essential to further evaluate long-term functional and aesthetic outcomes, as well as the impact of factors such as smoking and systemic comorbidities on flap survival. Furthermore, this study is limited by the absence of objective criteria for both functional and aesthetic evaluations. Additionally, there are no standardized measures for assessing morbidity at different donor sites and for objectively evaluating damage at the recipient site. Regarding donor site issues, we primarily conducted an objective assessment based on the presence or absence of hypertrophic scars. However, we were unable to perform an evaluation using a scale. We believe that further research will be necessary in the future.

This study demonstrates that the thenar flap, partial toe pulp free flap, and RASP flap are effective methods for fingertip and pulp reconstruction. Each technique has distinct advantages: the thenar flap is ideal for small defects, the partial toe pulp free flap excels in moderate defects with superior aesthetic and sensory outcomes [12], and the RASP flap is best for larger defects. However, careful patient selection is crucial to optimize outcomes, as each method has its own limitations, including donor site morbidity and potential scarring. Further research with larger samples and longer follow-ups is needed to assess long-term outcomes and the impact of factors like smoking on flap survival.