HAND/PERIPHERAL NERVE The Dorsal Homodigital Island Flap Based on the Dorsal Branch of the Digital Artery: A Review of 166 Cases Chao Chen, M.D., Ph.D. Peifu Tang, M.D., Ph.D. Xu Zhang, M.D., Ph.D. Beijing, Qinhuangdao, and Chengde, People’s Republic of China
Background: Soft-tissue reconstruction in the finger continues to evolve. This study reports reconstruction of small to moderate finger defects with the dorsal homodigital island flap and compares the results between the innervated and noninnervated flaps. Methods: A retrospective study was conducted of 166 patients who had soft-tissue defects of the finger treated with the dorsal homodigital island flap (187 defects in 187 fingers in 166 patients). Mean defect size and flap size were 2.2 × 1.9 cm and 2.4 × 2.1 cm, respectively. When return of sensation was important, the dorsal branch of the digital nerve or the dorsal digital nerve was attached with the flap to restore neurosensory function. The main outcomes were static two-point discrimination and Semmes-Weinstein monofilament scores of the flap, fingertip pain, and joint motion. Results: A significant difference was found between the innervated and noninnervated flaps in two-point discrimination, Semmes-Weinstein monofilament, and fingertip pain. The dual-innervated flap presented better discriminatory sensation on the flap and a lower incidence of fingertip pain than the noninnervated and single-innervated flap. In addition, the innervated flap obtained better Semmes-Weinstein monofilament scores than the noninnervated flap. For flaps harvested from the middle phalanx, the mean active motion arc of the distal interphalangeal joint was 69 degrees (range, 35 to 90 degrees). The contralateral side measured 73 degrees (range, 45 to 90 degrees) (significant difference, p = 0.041). Maximum amplitude losses of 15 degrees were seen in 10 percent of patients in the distal interphalangeal joint. Conclusion: The dorsal homodigital island flap is an alternative for tissue reconstruction in the finger. (Plast. Reconstr. Surg. 133: 519e, 2014.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, Ⅲ.
S
oft-tissue reconstruction in the finger continues to evolve. Appropriate therapy should preserve the aesthetic appearance, provide sensate coverage without pain in important anatomical regions, and minimize donor-site morbidity.1 Based on these principles, the dorsal From the Department of Orthopedics, Chinese PLA General Hospital; Hand Surgery Department, Second Hospital of Qinhuangdao; and Chengde Medical College. Received for publication June 7, 2013; accepted October 16, 2013. This trial is registered under the name “The Dorsal Homodigital Island Flap Based on the Dorsal Branch of the Digital Artery: A Review of 171 Cases,” Clinical Trials.gov identification number NCT01871103 (http://clinicaltrials.gov/ct2/show/NCT01871103). Copyright © 2014 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0000000000000016
homodigital island flap may be a reliable alternative for reconstructing small to moderate defects of the fingers. As described in previous anatomical studies, the distribution of the dorsal branches of the digital artery is relatively constant.2 At the level of the middle and distal thirds of the proximal phalanx, the middle third of the middle phalanx, and the distal interphalangeal joint, the digital artery branches off the four largest dorsal branches of the digital artery (Fig. 1).3,4 Based on these dorsal branches of the digital artery, the different dorsal digital flaps can be selected for various reconstructive requirements.5,6
Disclosure: The authors have no financial disclosures to make or any conflicts of interest to disclose.
www.PRSJournal.com
519e
Plastic and Reconstructive Surgery • April 2014 PATIENTS AND METHODS
Fig. 1. The dorsal branches of the digital artery in each phalanx show a regular repetitive distribution. There are four major dorsal branches that can be selected as the vascular pedicle of a flap for tissue reconstruction.
The dorsal homodigital island flap, first described by Bertelli and Pagliei7 in 1994, is an axial fasciocutaneous island flap based on the dorsal branches of the digital artery, which uses the dorsal skin of the injured finger to provide soft-tissue coverage for a volar defect. Since then, dorsal homodigital island flaps based on the different levels of dorsal branches of the digital artery have been described for use in a variety of clinical situations. However, until now, it has only been described for tissue reconstruction in a certain position, such as the fingertip or pulp or the middle or proximal phalanx.8–10 In addition, a retrospective study on the dorsal homodigital island flap with a large sample has not been found in the literature. The aim of this retrospective study was to evaluate the efficacy of the dorsal homodigital island flap for tissue reconstruction in different regions of the finger. For tissue reconstruction in regions where sensory return is important, such as the fingertip, the pulp, the volar aspect of the finger, the radial aspect of the index finger, and the ulnar aspect of the little finger, we compared sensory recovery among noninnervated, single-innervated, and dual-innervated dorsal homodigital island flaps. For fingertip and pulp reconstructions, we compared fingertip pain among three types of dorsal homodigital island flaps. We also compared active motion of the joints between the reconstructed finger and the opposite hand.
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A retrospective study was conducted that included 166 patients who had soft-tissue defects of the finger treated with the dorsal homodigital island flap from 2004 to 2009. The patients included in the study were selected from all 212 patients who had tissue reconstructed with the dorsal homodigital island flap in our hand surgery center. Of these, 29 patients were lost to follow-up and 12 patients with a follow-up period less than 16 months were excluded from the study. To assess exclusion bias, we compared the demographic characteristics and the injuries between these and the patients of the study group. No significant differences were found for patient age, sex, dominant hand, injury mechanism, or defect size. Based on the mechanism of injury, five patients with sharp injuries were also excluded because the sample size was small and the mechanism was quite different from avulsion or crush injury. The patients remaining in the study included 135 male and 31 female patients with an average age of 32 years (range, 17 to 52 years). The causes of the defects were avulsion (n = 95) and crush (n = 71). There were 187 soft-tissue defects in 187 fingers in 166 patients. Single-finger defects were noted in 152 cases and multiple-finger defects were noted in 14 cases. The injured fingers included 56 index, 67 long, 51 ring, and 13 little fingers. In this series, the size of the defects ranged from 1.8 to 2.7 cm long (mean, 2.2 cm) and 1.6 to 2.2 cm wide (mean, 1.9 cm). Emergency surgery was conducted in 143 patients, whereas elective surgery was noted in 23 patients. Inclusion criteria included the following: (1) a soft-tissue defect with exposed bone or tendon in one finger or in multiple fingers; (2) a defect greater than 1.5 cm and less than 3 cm in length; and (3) a patient aged 15 to 60 years. Exclusion criteria included the following: (1) injuries to the dorsum of the finger or to the course of the vascular pedicle that precluded its use as the donor; (2) a defect less than or equal to 1.5 cm or greater than or equal to 3 cm in length; and (3) a soft-tissue defect of the thumb. Patients younger than 15 years were also excluded because of the likely inability to accurately or reliably self-report measurement. Operative Technique There was no need to use the Doppler probe to locate the dorsal artery because of its anatomical constancy. The operation was carried out under axillary plexus anesthesia with the aid of tourniquet control. The flap was designed over the dorsum of the middle or proximal phalanx
Volume 133, Number 4 • Dorsal Homodigital Island Flap of the injured finger. According to the location of the defect, we selected the nearest uninjured dorsal branches of the digital artery to the defect as the vascular pedicle of the flap. For the distal phalanx defects, the flap was raised from the dorsum of the middle phalanx (Fig. 2). Defects of the middle or proximal phalanx were covered by the flap from the proximal phalanx (Figs. 3 and 4). The flap size was designed 10 to 15 percent larger than the defect. The initial incisions were made along the free edges of the flap. The flap was then harvested with preservation of the tenosynovium. From the proximal edge of the flap to the starting point of the dorsal branch of the digital artery, a strip of subcutaneous tissue 8 mm in width surrounding the dorsal branches of the digital artery was included in the pedicle. A strip of skin 3 mm in width was harvested with the pedicle to avoid compression after flap transfer. After that, the pedicle was released to the pivot point. Thus, the maximal pedicle length was achieved. For a defect where return of sensation was important, the dorsal branch of the digital nerve or the dorsal digital nerve could be harvested with the flap to restore neurosensory function. When the flap was harvested from the middle phalanx, the dorsal branch of the digital nerve was included in the flap (Fig. 2). When the flap was harvested from the proximal phalanx, the dorsal digital nerve was included as a donor nerve (Fig. 3). An additional length of nerve branch, based on the
distance between the defect and the nerve end of the injured finger, was harvested for a t ension-free neurorrhaphy, especially in cases with digital nerve avulsion. The flap was transferred to the defect through an open tunnel. The donor defects were resurfaced with the split-thickness skin graft, and the graft was bolstered with tie-over dressings. Figure 5 presents a case in which a bilaterally innervated dorsal homodigital island flap was used for fingertip reconstruction. Figures 6 and 7 and Figures 8 through 10 show two cases in which the dorsal homodigital island flap was used for reconstructing a volar defect at the distal interphalangeal joint level and a dorsal defect in the middle phalanx, respectively. Postoperative Management After surgery, the hand was elevated to minimize venous congestion. The patients who underwent nerve repair were protected with a splint, with the interphalangeal joint in full extension and the metacarpophalangeal joint in 70 degrees of flexion. The patients had the splint removed and started active range-of-motion exercises with the help of a physical therapist after 3 weeks. Tactile stimulation was applied to the recipient site and continued until the patient returned to work. Evaluation of Outcomes At final follow-up, sensory restoration of the flap was measured using the static two-point
Fig. 2. (Left) The dorsal homodigital island flap is harvested from the dorsum of the middle phalanx and receives its blood supply from the end dorsal branch of the digital artery. One dorsal branch of the digital nerve is included in the flap. (Right) Neurorrhaphy is completed between the dorsal branch of the digital nerves and the digital nerves at the recipient site.
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Plastic and Reconstructive Surgery • April 2014 interphalangeal joints were measured. For the proximal phalanx dorsal homodigital island flap, the metacarpophalangeal and proximal interphalangeal joints were measured. The motion arcs of the reconstructed fingers were compared with those of the opposite side. We also evaluated color matching of the skin graft in the donor defect, which was classified as normal, hypopigmented and hyperpigmented.13 All tests were performed by the same senior surgeon (C.C.), who was blinded to the procedures.
Fig. 3. The dorsal homodigital island flap is harvested from the dorsum of the proximal phalanx and receives its blood supply from the dorsal arterial branch originating at the level of the middle of the middle phalanx. One dorsal digital nerve is attached with the flap.
Statistical Analysis Quantitative variables were described as means and standard deviations (for symmetric distribution) or medians and interquartile range (for asymmetric distribution). Categorical variables were described as absolute and relative frequencies (nominal variable) or medians and interquartile range (ordinal variable). The t test (symmetric distribution) or the Mann-Whitney test (asymmetric distribution) was applied to compare the two groups in relation to the quantitative outcomes. When evaluating the three types of techniques, one-way analysis of variance (symmetric distribution), the Pearson chi-square test (nominal categorical variable), or the Kruskal-Wallis test (ordinal categorical variable) was applied. The level of significance was set at 5 percent, where p
Background: Soft-tissue reconstruction in the finger continues to evolve. This study reports reconstruction of small to moderate finger defects with the dorsal homodigital island flap and compares the results between the innervated and noninnervated flaps. Methods: A retrospective study was conducted of 166 patients who had soft-tissue defects of the finger treated with the dorsal homodigital island flap (187 defects in 187 fingers in 166 patients). Mean defect size and flap size were 2.2 × 1.9 cm and 2.4 × 2.1 cm, respectively. When return of sensation was important, the dorsal branch of the digital nerve or the dorsal digital nerve was attached with the flap to restore neurosensory function. The main outcomes were static two-point discrimination and Semmes-Weinstein monofilament scores of the flap, fingertip pain, and joint motion. Results: A significant difference was found between the innervated and noninnervated flaps in two-point discrimination, Semmes-Weinstein monofilament, and fingertip pain. The dual-innervated flap presented better discriminatory sensation on the flap and a lower incidence of fingertip pain than the noninnervated and single-innervated flap. In addition, the innervated flap obtained better Semmes-Weinstein monofilament scores than the noninnervated flap. For flaps harvested from the middle phalanx, the mean active motion arc of the distal interphalangeal joint was 69 degrees (range, 35 to 90 degrees). The contralateral side measured 73 degrees (range, 45 to 90 degrees) (significant difference, p = 0.041). Maximum amplitude losses of 15 degrees were seen in 10 percent of patients in the distal interphalangeal joint. Conclusion: The dorsal homodigital island flap is an alternative for tissue reconstruction in the finger. (Plast. Reconstr. Surg. 133: 519e, 2014.) CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, Ⅲ.
S
oft-tissue reconstruction in the finger continues to evolve. Appropriate therapy should preserve the aesthetic appearance, provide sensate coverage without pain in important anatomical regions, and minimize donor-site morbidity.1 Based on these principles, the dorsal From the Department of Orthopedics, Chinese PLA General Hospital; Hand Surgery Department, Second Hospital of Qinhuangdao; and Chengde Medical College. Received for publication June 7, 2013; accepted October 16, 2013. This trial is registered under the name “The Dorsal Homodigital Island Flap Based on the Dorsal Branch of the Digital Artery: A Review of 171 Cases,” Clinical Trials.gov identification number NCT01871103 (http://clinicaltrials.gov/ct2/show/NCT01871103). Copyright © 2014 by the American Society of Plastic Surgeons DOI: 10.1097/PRS.0000000000000016
homodigital island flap may be a reliable alternative for reconstructing small to moderate defects of the fingers. As described in previous anatomical studies, the distribution of the dorsal branches of the digital artery is relatively constant.2 At the level of the middle and distal thirds of the proximal phalanx, the middle third of the middle phalanx, and the distal interphalangeal joint, the digital artery branches off the four largest dorsal branches of the digital artery (Fig. 1).3,4 Based on these dorsal branches of the digital artery, the different dorsal digital flaps can be selected for various reconstructive requirements.5,6
Disclosure: The authors have no financial disclosures to make or any conflicts of interest to disclose.
www.PRSJournal.com
519e
Plastic and Reconstructive Surgery • April 2014 PATIENTS AND METHODS
Fig. 1. The dorsal branches of the digital artery in each phalanx show a regular repetitive distribution. There are four major dorsal branches that can be selected as the vascular pedicle of a flap for tissue reconstruction.
The dorsal homodigital island flap, first described by Bertelli and Pagliei7 in 1994, is an axial fasciocutaneous island flap based on the dorsal branches of the digital artery, which uses the dorsal skin of the injured finger to provide soft-tissue coverage for a volar defect. Since then, dorsal homodigital island flaps based on the different levels of dorsal branches of the digital artery have been described for use in a variety of clinical situations. However, until now, it has only been described for tissue reconstruction in a certain position, such as the fingertip or pulp or the middle or proximal phalanx.8–10 In addition, a retrospective study on the dorsal homodigital island flap with a large sample has not been found in the literature. The aim of this retrospective study was to evaluate the efficacy of the dorsal homodigital island flap for tissue reconstruction in different regions of the finger. For tissue reconstruction in regions where sensory return is important, such as the fingertip, the pulp, the volar aspect of the finger, the radial aspect of the index finger, and the ulnar aspect of the little finger, we compared sensory recovery among noninnervated, single-innervated, and dual-innervated dorsal homodigital island flaps. For fingertip and pulp reconstructions, we compared fingertip pain among three types of dorsal homodigital island flaps. We also compared active motion of the joints between the reconstructed finger and the opposite hand.
520e
A retrospective study was conducted that included 166 patients who had soft-tissue defects of the finger treated with the dorsal homodigital island flap from 2004 to 2009. The patients included in the study were selected from all 212 patients who had tissue reconstructed with the dorsal homodigital island flap in our hand surgery center. Of these, 29 patients were lost to follow-up and 12 patients with a follow-up period less than 16 months were excluded from the study. To assess exclusion bias, we compared the demographic characteristics and the injuries between these and the patients of the study group. No significant differences were found for patient age, sex, dominant hand, injury mechanism, or defect size. Based on the mechanism of injury, five patients with sharp injuries were also excluded because the sample size was small and the mechanism was quite different from avulsion or crush injury. The patients remaining in the study included 135 male and 31 female patients with an average age of 32 years (range, 17 to 52 years). The causes of the defects were avulsion (n = 95) and crush (n = 71). There were 187 soft-tissue defects in 187 fingers in 166 patients. Single-finger defects were noted in 152 cases and multiple-finger defects were noted in 14 cases. The injured fingers included 56 index, 67 long, 51 ring, and 13 little fingers. In this series, the size of the defects ranged from 1.8 to 2.7 cm long (mean, 2.2 cm) and 1.6 to 2.2 cm wide (mean, 1.9 cm). Emergency surgery was conducted in 143 patients, whereas elective surgery was noted in 23 patients. Inclusion criteria included the following: (1) a soft-tissue defect with exposed bone or tendon in one finger or in multiple fingers; (2) a defect greater than 1.5 cm and less than 3 cm in length; and (3) a patient aged 15 to 60 years. Exclusion criteria included the following: (1) injuries to the dorsum of the finger or to the course of the vascular pedicle that precluded its use as the donor; (2) a defect less than or equal to 1.5 cm or greater than or equal to 3 cm in length; and (3) a soft-tissue defect of the thumb. Patients younger than 15 years were also excluded because of the likely inability to accurately or reliably self-report measurement. Operative Technique There was no need to use the Doppler probe to locate the dorsal artery because of its anatomical constancy. The operation was carried out under axillary plexus anesthesia with the aid of tourniquet control. The flap was designed over the dorsum of the middle or proximal phalanx
Volume 133, Number 4 • Dorsal Homodigital Island Flap of the injured finger. According to the location of the defect, we selected the nearest uninjured dorsal branches of the digital artery to the defect as the vascular pedicle of the flap. For the distal phalanx defects, the flap was raised from the dorsum of the middle phalanx (Fig. 2). Defects of the middle or proximal phalanx were covered by the flap from the proximal phalanx (Figs. 3 and 4). The flap size was designed 10 to 15 percent larger than the defect. The initial incisions were made along the free edges of the flap. The flap was then harvested with preservation of the tenosynovium. From the proximal edge of the flap to the starting point of the dorsal branch of the digital artery, a strip of subcutaneous tissue 8 mm in width surrounding the dorsal branches of the digital artery was included in the pedicle. A strip of skin 3 mm in width was harvested with the pedicle to avoid compression after flap transfer. After that, the pedicle was released to the pivot point. Thus, the maximal pedicle length was achieved. For a defect where return of sensation was important, the dorsal branch of the digital nerve or the dorsal digital nerve could be harvested with the flap to restore neurosensory function. When the flap was harvested from the middle phalanx, the dorsal branch of the digital nerve was included in the flap (Fig. 2). When the flap was harvested from the proximal phalanx, the dorsal digital nerve was included as a donor nerve (Fig. 3). An additional length of nerve branch, based on the
distance between the defect and the nerve end of the injured finger, was harvested for a t ension-free neurorrhaphy, especially in cases with digital nerve avulsion. The flap was transferred to the defect through an open tunnel. The donor defects were resurfaced with the split-thickness skin graft, and the graft was bolstered with tie-over dressings. Figure 5 presents a case in which a bilaterally innervated dorsal homodigital island flap was used for fingertip reconstruction. Figures 6 and 7 and Figures 8 through 10 show two cases in which the dorsal homodigital island flap was used for reconstructing a volar defect at the distal interphalangeal joint level and a dorsal defect in the middle phalanx, respectively. Postoperative Management After surgery, the hand was elevated to minimize venous congestion. The patients who underwent nerve repair were protected with a splint, with the interphalangeal joint in full extension and the metacarpophalangeal joint in 70 degrees of flexion. The patients had the splint removed and started active range-of-motion exercises with the help of a physical therapist after 3 weeks. Tactile stimulation was applied to the recipient site and continued until the patient returned to work. Evaluation of Outcomes At final follow-up, sensory restoration of the flap was measured using the static two-point
Fig. 2. (Left) The dorsal homodigital island flap is harvested from the dorsum of the middle phalanx and receives its blood supply from the end dorsal branch of the digital artery. One dorsal branch of the digital nerve is included in the flap. (Right) Neurorrhaphy is completed between the dorsal branch of the digital nerves and the digital nerves at the recipient site.
521e
Plastic and Reconstructive Surgery • April 2014 interphalangeal joints were measured. For the proximal phalanx dorsal homodigital island flap, the metacarpophalangeal and proximal interphalangeal joints were measured. The motion arcs of the reconstructed fingers were compared with those of the opposite side. We also evaluated color matching of the skin graft in the donor defect, which was classified as normal, hypopigmented and hyperpigmented.13 All tests were performed by the same senior surgeon (C.C.), who was blinded to the procedures.
Fig. 3. The dorsal homodigital island flap is harvested from the dorsum of the proximal phalanx and receives its blood supply from the dorsal arterial branch originating at the level of the middle of the middle phalanx. One dorsal digital nerve is attached with the flap.
Statistical Analysis Quantitative variables were described as means and standard deviations (for symmetric distribution) or medians and interquartile range (for asymmetric distribution). Categorical variables were described as absolute and relative frequencies (nominal variable) or medians and interquartile range (ordinal variable). The t test (symmetric distribution) or the Mann-Whitney test (asymmetric distribution) was applied to compare the two groups in relation to the quantitative outcomes. When evaluating the three types of techniques, one-way analysis of variance (symmetric distribution), the Pearson chi-square test (nominal categorical variable), or the Kruskal-Wallis test (ordinal categorical variable) was applied. The level of significance was set at 5 percent, where p
