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ORIGINAL ARTICLE
Year : 2022  |  Volume : 67  |  Issue : 4  |  Page : 343-348
Ingrown toenail treated by the modified howard–dubois technique: Long-term follow-up results


From the Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China

Date of Web Publication2-Nov-2022

Correspondence Address:
Jin Li
Department of Hand Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan - 430022
China
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijd.ijd_687_21

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   Abstract 


Background: According to the Mozena classification system, stage IIb and stage III ingrown toenail cases are considered as severe ones; however, limited options are available for treatment. Aims: To lower the recurrence rate and achieve primary intention healing in severe ingrown toenail cases by the modified Howard–Dubois technique. Methods: Forty patients were included in this study. In this procedure, a fish-mouth like soft tissue along the nail groove to the tip of the toe was resected, the upper surface of the distal phalanx was flattened and the nail bed matrix was remodelled. The European Quality of Life (EuroQol) questionnaire and Surgical Satisfaction Questionnaire were used to assess the outcomes. Results: There were no recurrences observed during the follow-up period. Healing time from surgery to back to school or work was 10.82 days on an average (range: 7–23 days). According to the results of EuroQol questionnaire, improvements were achieved in the areas of mobility (50%), looking after myself (10%), doing usual activities (35%), having pain or discomfort (95%) and feeling worried, sad, or unhappy (55%). According to the results of Surgical Satisfaction Questionnaire, 38 (95%) patients indicated that they would undergo the surgery again if they 'had to do it all over again' and 36 (90%) patients said that they would recommend the procedure to others. Conclusions: This modified Howard–Dubois technique was an effective, safe and cosmetic alternation for the treatment of ingrown toenail in severe or relapsed cases.


Keywords: Howard–Dubois technique, ingrown toenail, onychocryptosis, recurrence


How to cite this article:
Tian J, Chen Z, Li J. Ingrown toenail treated by the modified howard–dubois technique: Long-term follow-up results. Indian J Dermatol 2022;67:343-8

How to cite this URL:
Tian J, Chen Z, Li J. Ingrown toenail treated by the modified howard–dubois technique: Long-term follow-up results. Indian J Dermatol [serial online] 2022 [cited 2022 Dec 2];67:343-8. Available from: https://www.e-ijd.org/text.asp?2022/67/4/343/360350





   Introduction Top


Ingrown toenail, also known as onychocryptosis, is a nail disease with symptoms of pain, redness and swelling in the surrounding soft tissue. The great toe is commonly involved.[1] If the symptoms progress, infection may happen and even granulation can occur, which can affect the quality of life.

Previous studies have analysed the aetiology and proposed various conservative and surgical interventions. However, no consensus has been reached on what is the dominant cause or which is the best choice for treatment. The biggest debate on the aetiology of the ingrown toenail has mainly focused on whether the nail itself or excessive amount of soft tissues at the sides of the affected nail is a causative factor.[2] The treatment methods, such as simple nail avulsion, matricectomy with chemical agents/carbon dioxide laser/electrocautery, wedge resection without coagulation (Winograd's procedure) or with electrocoagulation, and Zadik's procedure, focus on the correction of the nail plate.[3],[4],[5],[6],[7],[8] On the contrary, Howard–Dubois, Vandenbos, Super U and Noël's procedures are effective options for the resection of excessive soft tissue, which focus on the hypertrophy of the nail folds.[9],[10],[11],[12] The effectiveness of these reported methods are restricted by different reasons, such as postoperative recurrence, cosmetic problem, complexity of manipulation, or prolonged curative duration, especially in severe or relapsed cases. If a surgeon does not take into account the underlying risks that may cause the symptoms, relapse can occur.[13] To reduce the risk of recurrence and to restore the native configuration of the nail plate and nail fold in severe or relapsed cases, we conceived a three-step procedure named as modified Howard–Dubois technique. With this technique, the surrounding bulky soft tissue was resected, upper surface of the distal phalanx was flattened and curvature of the nail bed was remodelled. Factors that might play a role in the development of ingrown toenail, such as hypertrophy of the surrounding soft tissue, pathological changes in the nail plate, or abnormality in the phalanx, were all taken into consideration and resolved.

The most common limitation in literature was mainly the short period of follow-up. Certain complications could be unrevealed by this limitation, which might lead to uncertainty of surgical intervention. It has been 10 years since this technique was performed for the first time. The patients who underwent this procedure were followed-up for long-term to reveal more information about the final outcomes.


   Materials and Methods Top


Forty patients (26 men and 14 women), admitted to our department between January 2010 and December 2014, were selected and signed the agreement of participation in this study. Twenty-six patients were considered with severe condition for the first time and fourteen relapsed cases. The mean age of the patients was 26.12 years (range: 12–49 years). All the patients underwent the same procedure in our department.

After disinfection was performed, regional anaesthesia was administered with 5 mL of 2% lidocaine. A simple tourniquet cut from a glove was made and wrapped tightly around the base of the involved toe. As described by Howard–Dubois,[9] a fish-mouth like incision was made along the nail groove around the tip of the involved toe. Leaving a 3–5 mm wide stripe of skin intact below the lateral nail grooves and tip of the toe was important. Subsequently, a second incision was made close to the first incision to create a wedge of skin and soft tissue, which would be removed [Figure 1]b. The width of the crescent was determined by the degree of hypertrophy of the soft tissue or the depth of the nail plate that was buried in the nail fold. After those steps of Howard–Dubois technique, further modification was made as follows: the periosteum dissector was used to detach the nail bed from the distal phalanx [Figure 1]c. The dorsal part of the phalanx was removed by a bone rongeur to flatten the dorsal surface of the distal phalanx [Figure 1]d, which was important to reduce the degree of curvature of the nail bed after closing the wound. The wound edges were approximated to achieve primary intention closure. If necessary, an extra strip of soft tissue was re-excised from the lower edge of the wound as indicated in [Figure 1]b. This was important to keep the nail edge that was buried in the soft tissue out of the bulky tissue after suturing [Figure 1]f. Simple interrupted sutures were given to close the wound directly.
Figure 1: A patient with relapsed ingrown toenail. (a): Infection and oozing occurred again after nail avulsion. (b): A wedge of skin and soft tissue was removed (yellow arrow). An extra strip of soft tissue (black arrow) should be resected if it was not enough to make the edge of nail plate out of the bulky tissue after suturing. (c): The nail bed was detached from the distal phalanx using the periosteum dissector. (d and e): The dorsal part of the phalanx was removed by a bone rongeur to flatten the dorsal surface of the distal phalanx. (f): The wound edges were approximated to achieve primary intention closure. (g): The appearance of the involved great toe 8 years after surgery.

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The standard of recurrence was defined as: similar symptoms occurred or the relationship between the nail plate and surrounding soft tissue returned to the state before surgery. Furthermore, outcomes, such as complications, healing time, pain, functional status, quality of life, and patient satisfaction, were evaluated. Complications, such as infection in the involved tissue, bleeding of the wound and unacceptable appearance of the toe after surgery, were recorded. Healing time was calculated in days from the date of surgery to returning to school or work. Pain, functional status and quality of life before and after surgery were assessed using the European Quality of Life (EuroQol) questionnaire. The five dimensions of this questionnaire: mobility, looking after myself, doing usual activities, having pain or discomfort, and feeling worried, sad, or unhappy were asked and recorded.[14] The Surgical Satisfaction Questionnaire was used to assess the final degree of satisfaction of the whole procedure.[15] The Statistical Package for the Social Sciences software version 23 (SPSS 23) and Microsoft Excel 2010 were used for the data analysis and statistical calculations. Results are presented as percentages or mean standard deviation. This study was approved by the Ethics Committee of the Tongji Medical College, Huazhong University of Science and Technology on January 4th, 2010.


   Results Top


Among the included forty cases, one foot was involved in 31 patients, while both feet were involved in nine patients. The duration from the onset of the symptoms was 17.5 months on an average. Based on the Mozena classification system, 23 cases were stage IIb and 17 cases were stage III. No recurrences were observed during the follow-up period among the 40 patients [Figure 1], [Figure 2], [Figure 3]. Healing time from surgery to back to school or work was 10.82 days on an average (range: 7–23 days). Clinical patient characteristics and outcomes after surgery are presented in [Table 1]. Based on the EuroQol questionnaire [Table 2], improvements were achieved in the areas of mobility (50%), looking after myself (10%), doing usual activities (35%), having pain or discomfort (95%) and feeling worried, sad, or unhappy (55%). The results of Surgical Satisfaction Questionnaire are recorded in [Table 3]. Thirty-eight (95%) patients indicated that they would have the surgery again if they 'had to do it all over again' and 36 (90%) patients said that they would recommend the procedure to others. Four patients (10%) experienced one or more minor complications within the first 2 months of surgery. These complications included infection (2.5%) or bleeding (7.5%).
Figure 2: A young woman with severe ingrown toenail. (a): Preoperative photograph. (b): Postoperative image 7 years after surgery

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Figure 3: A taxi driver with relapsed ingrown toenail. (a): Preoperative photograph. (b): Postoperative image 8 years after surgery

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Table 1: Clinical patient characteristics and outcomes after surgery

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Table 2: Patients rating of pain and functional status using European Quality of Life questionnaire

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Table 3: Patients reaction on the Surgical Satisfaction Questionnaire

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   Discussion Top


Ingrown toenail is a nail disease that is not life-threatening, but is rather troublesome. The biggest challenge in the treatment of this disease is recurrence, which is highly related with the confusing aetiology and mechanism of pathogenesis. Regarding the aetiology, excessive round or short trimming of the toenail is a common cause, leading to inflammatory reaction and necrosis. Other causes, such as inappropriate size of shoes, which pushes the nail plate against the nail fold, may also cause ingrown toenails.[16] Drugs are also found to be the risk factor that can result in ingrown toenail.[17],[18] Congenital factor is quite rare, which may be due to intrauterine trauma or hereditary transmission.[19] In cases of tinea unguium or onychomycosis, abnormal nail shapes may be at a greater risk of ingrown toenail.[20] The most commonly accepted theory in the mechanism of pathogenesis is that the lateral spicule of the nail plate penetrates into the skin tissue, resulting in early symptom of pain and later causes granulation formation.[13],[16] On the contrary, another theory states that the real problem is the excess amount of soft tissue surrounding the nail and not the nail plate.[21] Pearson and colleagues[22] failed to demonstrate any abnormality of the nail in patients with symptomatic ingrown toenails, and suggested that treatment should not be based on the correction of a non-existent nail deformity. The nail plate was always preserved in our procedure as we believed that there was no need of nail plate removal. Moreover, even if the configuration of the nail plate changed significantly, we still believed that it was caused by some other reasons, but not by the nail plate itself. Other researchers have hypothesised that certain unknown factors might cause nail bed shrinkage. The ventral nail plate subsequently begins to shrink, whereas the dorsal nail plate is not affected and develops normally. The difference between the unaffected dorsal site and affected ventral site leads to an inward twisting distally.[23] Baran reported that the overcurvature of a nail plate is most probably due to an enlarged base of the distal phalanx to which the matrix is firmly bound by ligament-like collagen fibres.[13] Li reported that more than half the patients in the recalcitrant ingrown toenail group had an upturned deformity through radiographic image.[24] Córdoba-Fernández et al.[25] studied the relationship between the abnormal hallux interphalangeal angle and risk of ingrown toenail, and revealed that the existence of a pathological hallux interphalangeal angle promoted the genesis of the disease. In this study, we focused on the status of the distal phalanx and assumed that any abnormal change in the distal phalanx was a latent risk, which could imbalance the relationship between the nail plate and surrounding soft tissue. The aetiologies are multiple and the mechanisms are divergent. No agreement has been reached. This is the most difficult point in the treatment of ingrown toenail because it is impossible to locate the dominant cause accurately and terminate it consequently. Any of the factors that can change the environment of the toenail or imbalance the normal relationship between the nail plate and surrounding soft tissue may lead to the recurrence of ingrown toenail.[26]

Various conservative and surgical methods are used to treat onychocryptosis according to the different mechanisms; however, it is still difficult to decide the proper treatment. The disease was classified as stage I, stage IIa, stage IIb, and stage III based on the degree of severity.[27] According to this classification, the conservative methods are usually indicated for stage I and stage IIa, while surgical interventions are indicated for stages IIb and III. Simplicity, low recurrence, short healing time, safety and cosmesis, and cost-effectiveness are always the goals to achieve, irrespective of the method chosen. Simple nail avulsion is a simple procedure to perform; however, it has a high recurrence rate (approximately 70%).[28] Chemical matricectomy is effective with a relatively lower recurrence rate. Moreover, multiple chemical agents can be used, which makes its application convenient. However, complications, such as excessive damage, local or systemic toxicity, and drainage were, reported.[4],[29],[30],[31] Wedge resection (Winograd technique) or Zadik's procedure was considered a radical method, but was capable of curing the disease permanently.[32] However, disfigurement due to the narrowing of the nail plate made the procedure unacceptable to those patients who cared about appearance of the toe. According to the result of a Cochrane review paper, wedge resection has a high recurrence rate and poor cosmetic results.[2] Remodelling the tip of the great toe is an effective treatment in cases of nail growth disorders associated with hypertrophy of the tip and hyponychium of the toe with bone spur or bone overgrowth.[33] Among the reported surgical methods, Howard–Dubois, Vandenbos and Super U methods were effective in achieving low recurrence and excellent cosmetic outcomes.[34] In cases with mild degree of ingrown toenail, Howard–Dubois technique is the best choice. However, in severe cases, Vandenbos and Super U techniques should be chosen, but the wound has to be left for secondary intention healing. To achieve primary intention healing in severe cases, we modified the Howard–Dubois technique. As demonstrated in this procedure, a fish-mouth like soft tissue along the nail groove to the tip of the toe was resected, the upper surface of the phalanx was flattened and the curvature of nail bed was reduced. Meanwhile, no special surgical instrument was needed, making the procedure convenient to be used by surgeons in different hospitals. This technique, which aimed to eliminate the factors that were associated with the development of ingrown toenail, was effective for severe or frequently relapsed cases. The long-term follow-up results also revealed that the effectiveness of this method was valid, especially regarding cosmetic appearance, relief of pain and discomfort, and low recurrence rate.

The advantages of this technique were: (1) no recurrence. Although the cases included in this study were severe or relapsed cases, no recurrence was observed over the long period of follow-up. (2) Shorter time period back to work. It took only 2 weeks for complete primary intention healing. (3) No narrowing of the nail plate. As there was no ablation or destruction of the nail plate and nail matrix, cosmetic outcome was usually achieved after surgery. The disadvantages of this technique were: (1) complicated procedure. As the phalanx, nail bed, and soft tissue are all taken into account during the operation, it is complicated to deal with all the factors perfectly. (2) Pain after surgery. The operation performed on the bone and soft tissue made it quite painful 2–3 days after surgery. As it is an invasive method, only a small number of patients would opt for this procedure. However, once they accepted and underwent this procedure, 38 (95%) patients indicated that they would have the surgery again if they 'had to do it all over again' and 36 (90%) patients said that they would recommend the procedure to others. This procedure achieved the relief of symptoms and cosmetic appearance of the toe without recurrence or any other severe complications. In other words, this method was reliable and valid to use in severe or relapsed cases of ingrown toenails. However, the limitations of this study were mainly related to the small sample size that satisfied the inclusion criteria and patients lost to follow-up and the fact that patients could not be evaluated precisely because of the lack of quantitative measurement tool for evaluation after surgery.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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