Amputated Digit Replantations: Critical Digit Ischemia Timing, Temperature, and Other Predictors of Survival.

INTRODUCTION: A common consideration for replantation success is the ischemia time following injury and the preservation temperature. A classic principle within the hand surgery community describes 12 hours of warm ischemia and 24 hours of cold ischemia as the upper limits for digit replantation; however, these limits are largely anecdotal and based on older studies. We aimed to compare survival data from the large body of literature to aid surgeons and all those involved in the replantation process in hopes of optimizing success rates. METHODS: The PubMed database was queried on April 4th, 2023, for articles that included data on digit replantation survival in terms of temperature of preservation and ischemia time. All primary outcomes were analyzed with the Mantel-Haenszel method within a random effects model. Secondary outcomes were pooled and analyzed using the chi-square statistic. Statistical analysis and forest plot generation were completed with RevMan 5.4 software with odds ratios calculated within a 95% confidence interval. RESULTS: Our meta-analysis identified that digits preserved in cold ischemia for over 12 hours had significantly higher odds of replantation success than the amputated digits replanted with 0-12 hours of warm ischemia time ( P ≤ 0.05). The odds of survival in the early (0-6 hours) replantation group were around 40% greater than the later (6-12 hours) replantation group ( P ≤ 0.05). Secondary outcomes that were associated with higher survival rates included a clean-cut amputation, increased venous and arterial anastomosis, a repair that did not require a vein graft, and replants performed in nonsmokers ( P ≤ 0.05). DISCUSSION: Overall, these findings suggest that when predicting digit replantation success, time is of the essence when the digit has yet to be preserved in a cold environment. This benefit, however, is almost completely diminished when the amputated digit is appropriately maintained in a cold environment soon after injury. In conclusion, our results suggest that there is potential for broadening the ischemia time limits for digit replant survival outlined in the literature, particularly for digits that have been stored correctly in cold ischemia.

Overview and management of complications after digital replantations.

The main complications after digital replantation are discussed in this review article. These complications include vascular compromise, infection, partial necrosis, delayed union or nonunion, atrophy and so on. The countermeasures for these complications are reviewed and the authors' methods are also introduced and discussed.

Mini-Shaped Kiss Flap Design for Palmar and Digital Soft-Tissue Resurfacing.

BACKGROUND: Although palmar and digital soft-tissue resurfacing with intrinsic flaps may provide functional and aesthetic reconstruction, the donor site may result in a tight closure or need for a skin graft once the flap is raised. In this series, the "mini-shaped kiss flap" was used to increase the resurfacing efficiency and preserve hand function. METHODS: The mini-shaped kiss flaps, based on common palmar digital arteries (eg, princeps pollicis artery and ulnar palmar digital artery), were developed for the resurfacing of distal or proximal finger areas. The tiny skin paddles were "kissed" together and transferred as pedicled in proposed dimensions and shape. The flap size, donor/recipient site, perforator source, whether free or pedicled, surgical outcome, and donor-site morbidity were evaluated. RESULTS: Twenty mini-shaped kiss flaps were harvested for the purpose of palmar and digital resurfacing. The flap sizes varied from 3 × 1.2 cm to 5 × 2 cm. All 19 patients, aged 6 to 52 years (mean, 35 years), achieved successful reconstruction without major complications after 6- to 12-month follow-up. CONCLUSIONS: The mini-shaped kiss flap technique exhibited favorable surgical outcomes with excellent color and texture match to the recipient sites. The reverse midpalm, thenar, and hypothenar island flap can be raised at the cost of an unnoticeable linear scar with minimized functional compromise in the donor area. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Fingertip Replantation: Surgical Technique, Tips, and Tricks.

SUMMARY: Replantation of fingertip amputations restores the original tissue and is the ideal treatment to provide the best aesthetic and functional outcome. However, successful fingertip replantation is considered challenging because it requires supermicrosurgery techniques. This article provides a detailed surgical technique for fingertip replantation and the authors' preferences and recommendations. In the authors' experience, the most important factors for successful fingertip replantation are meticulous vascular dissection, reliable arterial repair, and venous anastomosis to avoid postoperative venous congestion. Proximal arterial dissection until pulsatile bleeding is encountered avoids the zone of vascular injury, and is particularly important in crush or avulsion amputations. Distal arterial dissection is performed until undamaged intima is identified. The authors believe anastomosis to the central artery is reliable even in a Tamai zone II amputation. When an arterial defect is present, the authors recommend using a vein graft to anastomose to the central artery. In addition, the authors highly recommend at least one venous anastomosis to avoid postoperative venous congestion. In Tamai zone I, available veins can be found on the palmar side of the pulp. It is important to search directly below the dermis and remove adipose tissue around the vessels to secure space for anastomosis. The authors consider nerve suture in Tamai zone I and II replantations inessential, because spontaneous sensory recovery can be expected. Postoperative management of venous congestion, spasm in artery, and arterial thrombosis are as important as surgery.

Reconstruction of the ulnar artery in Guyon's canal with an arterial graft: Anatomical study.

Ulnar artery thrombosis in Guyon's canal can lead to vascular insufficiency in the fingers. The recommended treatment is resection and reconstruction of the pathological area. A bypass may be necessary, which may be venous or arterial. Arterial bypasses have better long-term patency; however, they are a source of donor-site complications. We carried out an anatomical study on 11 upper limbs and 7 lower limbs from cadavers to identify a technically accessible arterial graft, of a diameter suitable for bypassing the ulnar artery in Guyon's canal and with acceptable scar sequelae (few predicted postoperative complications, discreet size and/or location of scar). Three grafts were considered: anterior interosseous artery, radial recurrent artery and descending genicular artery. The various grafts were dissected and harvested from cadaver specimens, then their lengths and diameters were measured. The diameter of the candidate grafts was compared to the diameter of the distal ulnar artery. The diameter of the descending genicular artery matched the ulnar artery better than the radial recurrent artery or the anterior interosseous artery (103% vs 44% and 67%, respectively). Mean graft length was 6.6 cm. The anatomical configuration of the descending genicular artery allowed Y-shaped bypasses to be performed. Harvesting this artery appears to cause little damage and allows bypasses up to 6 cm to be performed. Despite its smaller diameter making it necessary to perform a microvascular size adjustment, the anterior interosseous artery is a candidate graft because it is long enough (119 mm) and located near the surgical site. LEVEL OF EVIDENCE: V.

Double-pivot proper digital artery perforator flap for fingertip reconstruction.

BACKGROUND: Dorsal flap based on proper digital artery perforator has been commonly used in wound coverage of fingertip; yet a small diameter and short length poses a risk of pedicle kinking or occlusion. The present study aims to present our preliminary results of using a double-pivot perforator flap based on the end dorsal branch of proper digital artery to repair finger pulp defect. METHODS: We designed a double-pivot flap based on the end-dorsal perforator branch of proper digital artery, raised from the dorsal aspect of the middle phalanx, with inclusion of both the perforator and a section of the trunk of the artery. This modified procedure forms a pedicle with a larger diameter and length than traditional designs. Twelve patients (12 fingers) each with a soft-tissue defect of the fingertip were successfully treated and followed up in this retrospective study. RESULTS: All the flaps survived without showing any signs of necrosis; three cases presented with transient venous flow disorder, these self-resolving without requiring any additional treatment. At final follow-up (12-33 months, mean 20 months), mean static two-point discrimination on the flap was 7.0 mm (range, 6-9). CONCLUSION: The double-pivot proper digital artery flap serves as a reliable option in fingertip reconstruction offering added benefits of having greater rotation flexibility, a lower risk of vessel kinking or occlusion, and good recovery of cutaneous sensation.

[A V-Y shaped flap with digital artery nerve at metacarpophalangeal joint was used to repair the defect of middle and distal phalanx].

OBJECTIVE: To explore a surgical method for the reconstruction of volar soft tissue defect and sensory and vascular repair in middle and far phalangeal digits. METHODS: From January 2016 to January 2020, a total of 14 patients , 9 males and 5 females, ages ranging from 22 to 69 years old, and with volar soft tissue defects in the middle and distal digits 2 to 4, underwent surgical reconstruction using the V-Y shaped flap with digital artery and nerve at the metacarpophalangeal joint. The defect area was (2.0~2.5) cm×(1.5 ~2.0) cm. The procedure involved the harvest of a V-Y shaped flap with the digital artery and nerve from the metacarpophalangeal joint. Flap design, dissection of blood vessels and nerves, and anastomosis with the digital artery and nerve were performed according to a standardized protocol., Functional exercise of affected finger was initiated 3 weeks postoperatively. Subsequent assessments were conducted to evaluate finger pulp sensation, shape and other relevant parameters. According to the upper extremity functional evaluation standard set up by Hand Surgery Branch of Chinese Medical Association, the surgical outcomes were evaluated. RESULTS: All 14 cases demonstrated successful tissue transplantation, , with immediate recovery of sensation observed in 10 cases with distal finger pulp defects. Four patients with middle phalangeal defects experienced gradual sensory recovery within 2 to 3 months postoperatively. Thirteen patients were followed up for a mean duration of (8.8 ± 4.49) months, during which satisfactory outcomes were observed. The average two-point resolution of the finger pulp was 4-6mm, and sensory function evaluation yielded a score of S3 or above. Patients exhibited realistic finger shape, normal skin color and temperature, good wear resistance, and cold resistance. Furthermore, finger joint function was essentially normal. CONCLUSION: The V-Y shaped flap with digital artery and nerve at the metacarpophalangeal joint offers a suitable solution for repairing the defect of the middle or distal phalangeal finger. This technique is characterized by its simplicity, low risk, and favorable outcomes, including restored finger shape, blood supply and sensation. Moreover, high patient satisfaction was achieved.

The effect of dobutamine treatment on salvage of digital replantation and revascularization.

PURPOSE: One of the most common causes of a failure after replantation and revascularization surgeries is 'no reflow' from proximal artery that occurs, especially following crush and avulsion injuries. In this study, we aimed to evaluate the effect of dobutamine treatment on salvage of replanted and revascularized digits. METHODS: The patients with no reflow phenomenon detected in the salvage operations of replanted/revascularized digits between the years 2017 and 2020 were included in the study. Dobutamine treatment was infused at a rate of 4 µg·kg-1·min-1 intraoperatively and of 2 µg·kg-1 min-1 postoperatively. Demographic data (age, sex), digit survival rate, ischemia time, and level of injury were retrospectively analysed. Pre-infusion, intraoperative and postoperative values of cardiac index (CI), mean arterial pressure (MAP), and heart rate (HR) were recorded. RESULTS: The phenomenon of 'no reflow' was encountered in 35 digits of 22 patients who underwent salvage surgery due to vascular compromise. The survival rate in the revascularization group was 75%, while it was 42.1% in the replanted digits. Metaphysis level of proximal phalanx was the most common localization for 'no reflow' phenomenon. The least values of CI, MAP and HR to obtain sufficient perfusion in salvaged digits were as follows: 4.2 l.min-1.m-2, 76 mm Hg, and 83 beat·min-1, respectively. CONCLUSIONS: It was demonstrated that dobutamine infusion at a rate of 4 µg·kg-1·min-1 intraoperatively and at 2 µg·kg-1·min-1 postoperatively has favorable effects on the vascular compromise derived from no reflow of proximal artery.

Reverse homodigital artery versus reverse dorsal homodigital island flaps for fingertip defect repair: A meta-analysis.

PURPOSE: This review aimed to systematically and comprehensively compare the effectiveness and applicability of reverse homodigital artery island flaps (RHAIF) and reverse dorsal homodigital island flaps (RDHIF) to treat fingertip defects. METHODS: A comprehensive search was conducted in multiple databases for studies that compared RHAIF versus RDHIF for treating fingertip defects with no language restrictions from inception until July 31, 2022. A meta-analysis was performed using RevMan 5.4 software. RESULTS: A total of 14 articles were retrieved, comprising 484 patients (509 fingers) in the RHAIF group and 453 patients (484 fingers) in the RDHIF group. The pooled estimates suggested that patients treated with RHAIF experienced more donor-side complications and less postoperative venous crisis than patients in the RDHIF group. On the other hand, no significant differences were found in operative time, flap necrosis, static 2-point discrimination, moving two-point discrimination, total active motion, satisfaction rates and sensory recovery grade (S3+ to S4) between the RHAIF and RDHIF groups. CONCLUSIONS: No difference in effectiveness was found between the two surgical procedures for treating fingertip defects. Accordingly, the selection of the optimal approach should be based on the functional requirements of the patient and the surgeon's expertize.

Effects of external bleeding and hyperbaric oxygen treatment on Tamai zone 1 replantation.

INTRODUCTION: Tamai zone 1 replantation poses a challenge due to the very small size of the vascular structures; often there is no vein for anastomosis. Replantation may have to be done with only an arterial anastomosis. In our study, we aimed to evaluate the success of replantation by combining external bleeding and hyperbaric oxygen treatment (HBOT) in Tamai zone 1 replantation. METHODS: Between January 2017 and October 2021, 17 finger replantation patients who underwent artery-only anastomosis due to Tamai zone 1 amputation received 20 sessions of HBOT with external bleeding after the 24th postoperative hour. Finger viability was assessed at the end of treatment. A retrospective review of outcomes was performed. RESULTS: Seventeen clean-cut finger amputation patients were operated on under digital block anaesthesia with a finger tourniquet. No blood transfusion was required. In one patient, complete necrosis developed and stump closure was performed. Partial necrosis was observed in three patients and healed secondarily. Replantation in the remaining patients was successful. CONCLUSIONS: Vein anastomosis is not always possible in fingertip replantation. In Tamai zone 1 replantation with arteryonly anastomosis, post-operative HBOT with induced external bleeding appeared to shortened the hospital stay and was associated with a high proportion of successful outcomes.

Clinical application of an expanded reverse-island flap with two dorsal metacarpal arteries and dorsal metacarpal nerves in index- and middle-finger-degloving injury repair and amputation reconstruction.

The dorsal metacarpal artery flap (DMAF) is irrefutable as an effective way of repairing long finger defects, and hand surgeons might consider using it for long finger reconstruction or degloved injury repair. Unfortunately, the DMAF containing a single dorsal metacarpal artery (DMA) hinders the treatment effect. The sensory restoration of long fingers and the reconstruction of phalangeal joints and tendon grafts are unsolved challenges as well. We reported our experience in reconstructing the index and middle finger by a reverse-island flap with two DMAs and dorsal metacarpal nerves (DMNs) with blood supply. We reviewed ten patients with finger-crush injuries affecting eight index fingers and two middle fingers. Degloving injuries occurred in two patients, and finger amputations occurred in eight others. Two patients received simple flap reconstruction, and eight received finger reconstruction, including seven from abandoned phalangeal joints and tendon grafts of the severed finger and one from the iliac crest bone graft. All patients underwent finger reconstruction by an expanded reverse-island flap consisting of two DMAs and DMNs up to a maximal size of 9 × 8 cm2. Postoperative follow-up evaluation showed a satisfactory appearance and functional recovery of the reconstructed fingers. We posit that the expanded reverse-island flap involving two DMAs and DMNs constitutes a feasible and safe option for restoring a severely damaged index or middle finger, particularly for patients who are unwilling to undergo toe-to-finger transplantation to reconstruct the injured long fingers.

Reverse digital artery island flap with versus without sensory nerve coaptation for finger pulp reconstruction.

PURPOSE: Whether an innervated reverse digital artery island flap is superior to a non-innervated reverse digital artery island flap still remains controversial. We aimed to compare the clinical outcomes of the two flaps in repairing finger pulp soft tissue defects. METHODS: Medical records of patients who underwent finger pulp reconstruction between January 2007 and December 2017 were evaluated retrospectively. A total of 45 patients were included. Twenty underwent sensory nerve reconstruction with cutaneous branches of the proper digital nerve, and 25 underwent the surgery without sensory nerve reconstruction. Surgical results, complications and sensory function were collected for analysis. Sensory function was assessed by static two-point discrimination and the modified sensory evaluation standard of British Medical Research Council. RESULTS: The average operation time of innervated flaps was 23 min longer than non-innervated flaps. All 45 flaps survived completely. There was no significant difference in complications between groups. The average follow-up was 22 months. At the final follow-up, five non-innervated flaps had no recovery of static two-point discrimination. The average static two-point discrimination of the remaining 20 non-innervated flaps was larger than that of innervated flaps. Innervated flaps consistently achieved higher sensory function grades according to the modified sensory evaluation standard of British Medical Research Council. CONCLUSION: An innervated reverse digital artery island flap can achieve better sensory function recovery in a shorter time. This procedure did not increase the incidence of complications, although it extended the operation time. It has proven to be a good technique for finger pulp reconstruction.

Effect of dorsal nerve fascial island flap on repairing distal soft tissue defects at the proximal segment of the index, middle, ring, and little fingers.

BACKGROUND: To investigate the effect of the dorsal nerve fascial island (DNFI) flap on repairing finger soft tissue defects at the distal segments. METHODS: Fifty patients with distal soft tissue defects at the index, middle, ring, or little fingers were treated with a DNFI flap at the proximal phalanx between February 2008 and May 2018. The nutrient vascular chain around the dorsal branch of the proper palmar digital nerves served as the flap axis. The dorsal branch of the proper palmar digital arteries provided blood supply. The fascia pedicle served as the venous system. All patients were followed for 6 months. RESULTS: All 50 flaps survived. The appearance, color, and texture of the skin returned to normal. The sensory function was partially restored. The two-point discrimination of the finger flap was 7-10 mm. CONCLUSIONS: The DNFI flap at the proximal phalanges of the index, middle, ring, and little fingers is an effective surgical option. The technique has a high flap survival rate and long pedicle, which can repair different parts of the finger. The flap also restores the sensory function of the finger without damaging the main nerves or blood vessels. The flap treatment is an optimal option for finger soft tissue defects at the distal segments.

Treatment of resistant Raynaud's phenomenon with single-port thoracoscopic sympathicotomy: One-year follow-up.

OBJECTIVE: Follow-up of patients with treatment-resistant Raynaud's phenomenon (RP) one-year after single-port thoracoscopic sympathicotomy (SPTS). METHODS: Eight patients (six males, two females, median age of 45 years) with treatment-resistant RP underwent left-sided SPTS at the third rib (R3), unilaterally. Questionnaires were taken, and number and duration of RP attacks were reported over a 2-week period. Perfusion was assessed with a cooling and recovery procedure at baseline and one year after SPTS. Furthermore, laser speckle contrast analysis, pulse wave velocity, heart rate variability and nailfold capillary microscopy were performed. RESULTS: One year after SPTS the duration of the attacks of was reduced with 1.9 h in the left hand versus 0.3 h in the right hand. Furthermore, three aspects of the questionnaire showed a significant improvement (role limitations due to physical health (p = 0.017), pain (p = 0.027) and physical functioning (p = 0.025)). The total area under the curve of the total cooling and recovery procedure of the left hand was larger one year after surgery (101 (75-140) at baseline versus 118 (95-190) one year post-operatively, p = 0.012), implying a better perfusion in the fingers. This was mainly due to the improvement during the recovery phase (21 (1-41) at baseline versus 38 (24-43) one year post-operatively, p = 0.028). CONCLUSION: One year after unilateral R3 SPTS the benefit with regard to the majority of outcome variables persisted, though some effects seem to attenuate. Long-term effects and long-term follow-up results will be investigated in an on-going study. CLINICAL TRIAL REGISTRATION NUMBER: NCT02680509.

Facilitated harvesting of a radial artery superficial palmar branch flap for reconstruction of moderate finger skin defects.

Radial artery superficial palmar branch harvesting is technically challenging, especially for inexperienced hand surgeons. The short pedicle and a damaged recipient digital artery require proximal digital artery dissection and relatively long pedicles. Herein, we describe a facilitated flap elevation technique and its application in various cases. From 2013 to 2021, 10 patients with finger injuries received radial artery superficial palmar flaps. We assessed flap survival, sizes, complications, two-point discrimination, and the Semmes-Weinstein monofilament test results. The main shortcoming of a radial artery superficial palmar flap is its short pedicle. Therefore, we developed a long skin flap design in the long axis direction, and the accompanying vein was dissected proximally to the radial artery to obtain a long pedicle. All flaps survived. The median flap dimension was 5.0 × 2.2 cm (maximum size: 6.0 × 2.0 + 5.0 × 2.0 cm [for a bilobed flap]). While nerve reconstruction was performed in one patient, all patients had preserved sensation. A sufficiently long pedicle can be obtained by dissecting the accompanying vein proximally to the radial artery. Perforators found in the skin around the scaphoid tubercle in all cases suggest value in including this region in flap design. To obtain a longer pedicle, the flap was developed with the long-skin design in the long-axis direction. Although the accompanying vein is usually thin and difficult to anastomose with the finger vein, its proximal dissection led to the accompanying vein of the radial artery that facilitated the harvesting of a sufficiently long vein.

Flow-through Dorsoulnar Perforator Flap Repair of Soft-Tissue Defect of the Finger with Segmental Digital Arterial Defect.

The aim of this study was to investigate the feasibility of transferring the free flow-through dorsoulnar perforator flap to reconstruct severely injured fingers. From January 2015 to March 2019, 16 patients, 16 thumb or fingers volar partial defects concomitant with segmental digital arterial defects, were included in this study. The flow-through dorsoulnar perforator flaps were used to repair the finger wounds and reconstruct digit arteries. Sixteen fingers in 16 patients were successfully reconstructed and all flaps survived completely. At the final follow-up, the appearance of the affected fingers was aesthetically pleasing. Two-point discrimination of the fingertips was 7.5-11.0 mm. According to the Total Active Motion (TAM) method: nine fingers were excellent, four were good, and three were fair. The free flow-through dorsoulnar perforator flap can achieve the goal of mending finger soft-tissue conditions complicated with segmental digital arterial defects with good results. Key Words: Flow-through flaps, Perforator flap, Dorsoulnar artery, Soft-tissue defect.

A Finger Vein Feature Extraction Method Incorporating Principal Component Analysis and Locality Preserving Projections.

In the field of biometric recognition, finger vein recognition has received widespread attention by virtue of its advantages, such as biopsy, which is not easy to be stolen. However, due to the limitation of acquisition conditions such as noise and illumination, as well as the limitation of computational resources, the discriminative features are not comprehensive enough when performing finger vein image feature extraction. It will lead to such a result that the accuracy of image recognition cannot meet the needs of large numbers of users and high security. Therefore, this paper proposes a novel feature extraction method called principal component local preservation projections (PCLPP). It organically combines principal component analysis (PCA) and locality preserving projections (LPP) and constructs a projection matrix that preserves both the global and local features of the image, which will meet the urgent needs of large numbers of users and high security. In this paper, we apply the Shandong University homologous multi-modal traits (SDUMLA-HMT) finger vein database to evaluate PCLPP and add "Salt and pepper" noise to the dataset to verify the robustness of PCLPP. The experimental results show that the image recognition rate after applying PCLPP is much better than the other two methods, PCA and LPP, for feature extraction.

Management of Artery-Only Digit Replantation: A Systematic Review of the Literature.

BACKGROUND: Artery-only replantation may be necessary in circumstances when venous repair cannot be performed due to their size or vessel injury. Venous congestion of the replanted part is inevitable. A systematic review was performed to identify techniques for mitigating congestion and analyze the outcomes of those techniques. METHODS: A comprehensive literature search was performed to identify relevant articles related to artery-only replantation. An initial query identified 1286 unique articles. A total of 55 articles were included in the final review. Included studies were categorized by decongestive technique. Data from each article included the number of patients treated, level of amputation, graft use, anticoagulation or antiplatelet therapy, replant viability, and follow-up duration. Weighted averages were determined from studies that reported five or more digits. RESULTS: A total of 1498 individual digital replantations were described. Very rarely did studies report artery-only replantation proximal to the distal interphalangeal joint. An overall survival rate of 78.5 percent was found irrespective of technique but was variable based on each particular study. Studies utilizing medicinal leech therapy were more likely to report use of intravenous anticoagulation, whereas surface bleeding techniques were more likely to report use of topical or local anticoagulant. CONCLUSIONS: Lack of a vein for anastomosis should not be regarded as a contraindication to replantation. These digits instead require a method to establish reliable drainage sufficient to allow for low resistance inflow and maintain a physiologic pressure gradient across capillary beds. The surgeon should select a decongestive technique that best suits the patient and their specific injury.