Transverse Eponychial Flap For Nail Lengthening And Fingertip Reconstruction

Introduction: Fingertip injuries are frequented with loss of pulp and nail complex. Most reconstructive procedures provide either the soft tissue defect coverage or lengthen the nail.
Methods: Patients included were more than 10 years of age with fingertip injury of Allen type III and IV with intact eponychium. Transverse Eponychial Flap was used to lengthen the nail lost as well as provide defect coverage. Paired t test, chi square test and Pearson correlation and Mann Whitney test were used for statistical analysis.
Results: Seventeen digits were analyzed. The average lengthening of the nail achieved was 142.4%. The average nail length during follow up was 59.1% of contralateral, with average final nail lengthening achieved was 31%. Reconstruction with Transverse Eponychial flap alone was performed in 58.8% of digits. Four patients (23.52%) had complete near normal nail. Sixteen digits had satisfactory and higher results. With Transverse Eponychial Flap alone it was possible to completely cover 10 fingertips (58.8%), requiring local flaps or skin graft for the remaining cases. Obliquely orientated injuries (76.47%) were more likely to undergo the procedure.
Conclusion: The flap significantly lengthens the nail, and provides satisfactory results. We recommend the use of this flap in defects with Allen type III and IV fingertip injuries.


Introduction
Fingertip injuries are the commonest among hand trauma. These injuries are frequently associated with injuries of the onychial complex in the form of lacerations and loss of nail and nail bed. The importance to reconstruct this small, conspicuous, yet important functional part of the digit has been emphasized frequently in the past. [1][2][3][4][5][6][7][8][9][10][11][12][13] Historical review Techniques to provide length to the shortened nail bed are few. Some have used nail bed grafts 14 or excision of the scarred nail bed and allowing the normal nail to grow further 15 , while others have used the eponychium either by excising it 12 4,7,9,14 Bakhach in 1998. 7 Since then, three types of eponychial bipedicled, reverse placation, whereas, Wang et al simply excised the eponychium to expose the hidden nail and nail bed. 4,7,9,12 Anatomy Zook has described the nail complex as shown in Figure  1. 16 The perionychium includes the nail bed, nail fold, with surrounding soft tissue referred to as eponychium, paronychium, and hyponychium. Paronychium refers to the skin on each side of the nail, and hyponychium refers to the skin distal to the nail bed. The eponychium is the skin proximal to the nail that covers the nail fold. Extending distally from the eponychium onto the nail is the nail vest or cuticle. The white arc of the nail just distal to the eponychium, known as the lunula, is the distal extent of the germinal matrix.
Adani has described the eponychial cranio-caudal dimension of 5-6mm. 10 The lateral borders extend to the imaginary line as a cranial extension of the paronychial line, ulnarly and radially. The eponychium receives blood supply from the branches of digital artery. 16,17 Transverse Eponychial Flap (TEF) tissue. The eponychium is incised and based on radial or defect. This exposes lunula and lengthens the nail bed as blood supply from the dorsal skin vessels through the proximal arcade of the dorsal subungual vascular network of the distal phalanx originating from the volar digital artery. 16,17 Hence, the aim of the study is to evaluate the Transverse functions and analyze the resultant aesthetic and functional

Methods
This is a retrospective case series study conducted in the Department of Plastic Surgery and Burns at Tribhuwan University Teaching Hospital and National Academy of Medical Sciences (National Trauma Center and Bir Hospital) in Kathmandu over a period of 5 years, from February 2017 to April 2022. All cases were result of trauma. The department clearance for the study has been obtained.
Patients in the emergency room were evaluated for orientation of the wound into volar or dorsal, transverse or oblique (radial/ulnar), and the combinations as shown in Table 1 and Figure 2. 18 But mostly, these injuries occur in combined orientation. A combined but practical Table 2.  The inclusion criteria consisted of digital tip injuries involving loss of nail bed by more than half in transverse orientation, oblique orientation with loss of more than half on either radial or ulnar side, intact eponychium, intact remaining matrix, patients more than 10 years of age and without any life threatening comorbidities. Patients excluded were those less than 10 years of age, non-viable nail bed, complete distal phalangeal bone loss, amputated digit, and injury of the eponychium. Patients were counselled about the procedure and consent was taken.
A pro forma was designed. The following variables were noted as shown in depends on the presence of amount of tissue left on either side of the wound. Base would be appropriate where the loss is more. In situations where the loss is at the level of lunula in a transverse loss either side can qualify for the base.
tented from the tip and with light traction applied incision base. The incision was limited to the imaginary extension of paronychial line. In some instances, the cranial border could be extended further for few milliliters obliquely cranially.
pivoted towards the hyponychium and its borders sutured to the distal defect by 6/0 round bodied polypropylene suture as shown in Figure 5 the nail bed by exposing the proximal nail and / or nail  bed and also provided coverage of the defect, partially or completely. Partially covered defects were reconstructed digits were dressed and splinted.
All patients were requested to follow up on 4th, 9th and 14th postoperative days for dressing and suture removal.
nail bed (FN) and its derivatives were measured at this time. Satisfaction rates were divided into four categories, unsatisfactory for 0 to 5, satisfactory for 6 to 7, good for 8 to 9, and excellent for 10.
Statistical analysis was performed with the help of SPSS version 16. Paired t test, chi square test and Pearson correlation and Mann Whitney test were used.

Results
Seventeen patients with 18 digits were assessed for eligibility and proceeded for operation. One patient was lost to follow up. Results of remaining 17 digits were analyzed as shown the mean values. Majority patients were students (31.25%) followed by businessmen (18.75%    The mean area of the defect was 189.2mm2, ranging from 100 to 288mm2. Following debridement the mean length of the remaining nail bed (RN) of the injured digit was 3.8±1.8mm, resulting of mean X = 28.1%±11.9, with

Transverse Eponychial Flap
The mean length, breath and area of the transverse

New nail bed length (NN) and Final nail bed length (FN)
Immediately following the operation the new nail bed length (NN) measured from 5 to 15mm with mean of 8.   Eponychium in all operated digits were less distinct than 9 but that did not dissatisfy the patient. All patients were more concerned with the quality of new nail.
-nn = near normal; I = irregular; s = smooth, is considered as normal; considered as normal.  In the initial phases of the study, the nail was dissected out it back for splinting, but this demanded care for long time increasing the risk to the bed. Therefore, we limited our reducing wound care to just about 2 weeks.

New Nail bed length (NN) and Final Nail bed length (FN)
The average lengthening of the nail bed achieved by Bakhach was 3.75mm, where as in our study was about 4.65mm. 7 This length was measured immediately after completion of the procedure (NN), but later on follow up, we found that the length (FN) had decreased to 4.17mm.
to the reduction in swelling of the onychial-pulp complex.

Sensation
The combined occurrence of hypersensitivity and pain on cases, although decreasing in intensity, was alarming but no associations have been found. Hypersensitivity occurred and four only TEF. Such a phenomena is possibly due to the magnitude of injury (all were crush-avulsion) and time injury repaired cases, similar to our study, with an average follow up period of 5.9 years. 19

Nail aesthetics
Bakhach et al reported that their results ranged from very good to excellent, an almost normal appearance as compared to contralateral nail. 7 In our study, only 5 out of 17 (29.41%) had almost normal nail. All others had a combination of some normal and some abnormal aesthetic features. Such a large percentage of combined aesthetic features probably can be explained by very small remaining nail (RN), dissection out of the nail during operation in cases during the initial stage and poor care of these exposed nail bed.

Patient -Surgeon satisfaction
The surgeon was more skeptical about the results than the patient owing to the fact that surgeon had more unsatisfactory and no excellent views than patients. Both expressed almost equal satisfactory-good, in 14 digits by surgeon and in 15 by patients which might have been the reason for strong correlation between them. Bakhach et al had all their results good to excellent. 7 )

Limitations
Despite the number of years of the study, the case numbers were relatively few. Follow up was inconsistent. Only few reported physically and others sent the photographs of their digits.

Conclusion
of lengthening of the nail bed as well as providing has been achieved. The method was simple and quick to perform. It was easy and less morbid to perform without removing the remaining nail. Both patient and the surgeon accepted results satisfactorily with more on patient side. The disadvantage that we have encountered was the presence was raised and interpolated distally to the defect and sutured. A marked improvement in the length has been noticed. The nail is sutured back to provide splinting and protection.
crush-avulsion amputation at mid-shaft of distal phalangeal level with partial degloving of the pulp but surviving and nail avulsion. volar orientation. Using periosteal elevator the eponychium was dissected from the nail bed and a radially based transverse subeponychial nail bed was exposed giving new length to the nail defect reconstructed.