Needle fasciotomy versus limited fasciectomy for the treatment of Dupuytren's contractures of the fingers (Hand-2): study protocol for a randomised controlled trial.

BACKGROUND: Dupuytren's contractures (DC) are fibrous cords under the skin of the hand that cause one or more fingers to curl gradually and irreversibly towards the palm. These contractures are usually painless but can cause a loss of hand function. Two treatments for Dupuytren's contractures are widely used within the National Health Service (NHS) in the UK: removal of the contractures via surgery (limited fasciectomy) and division of the contractures via a needle inserted through the skin (needle fasciotomy). This study aims to establish the clinical and cost-effectiveness of needle fasciotomy (NF) versus limited fasciectomy (LF) for the treatment of DC in the NHS, in terms of patient-reported hand function and resource utilisation. METHODS/DESIGN: Hand-2 is a national multi-centre, two-arm, parallel-group randomised, non-inferiority trial. Patients will be eligible to join the trial if they are aged 18 years or older, have at least one previously untreated finger with a well-defined Dupuytren's contracture of 30° or greater that causes functional problems and is suitable for treatment with either LF or NF. Patients with a contracture of the distal interphalangeal joint only are ineligible. Eligible consenting patients will be randomised 1:1 to receive either NF or LF and will be followed up for 24 months post-treatment. A QuinteT Recruitment Intervention will be used to optimise recruitment. The primary outcome measure is the participant-reported assessment of hand function, assessed by the Hand Health Profile of the Patient Evaluation Measure (PEM) questionnaire at 12 months post-treatment. Secondary outcomes include other patient-reported measures, loss of finger movement, and cost-effectiveness, reported over the 24-month post-treatment. Embedded qualitative research will explore patient experiences and acceptability of treatment at 2 years post-surgery. DISCUSSION: This study will determine whether treatment with needle fasciotomy is non-inferior to limited fasciectomy in terms of patient-reported hand function at 12 months post-treatment. TRIAL REGISTRATION: International Standard Registered Clinical/soCial sTudy ISRCTN12525655. Registered on 18th September 2020.

Systematic Review of Replant Salvage and Cost Utility Analysis of Inpatient Monitoring After Digit Replantation.

PURPOSE: Digit replantation is a high-stakes procedure that has been shown to be cost-effective, especially for multiple-digit replantation. However, it is associated with prolonged lengths of stay (LOS) for monitoring and attempts at salvage. The cost-effectiveness of prolonged inpatient stays presumes that this is necessary and inherent to the replantation. We hypothesized that prolonged monitoring of replanted digits, in the hope of possible salvage after primary failure, is cost-ineffective due to the low rates of vascular compromise and salvage after replantation. METHODS: Using previously published data comparing quality adjusted life years lost after traumatic digit amputation versus digit replantation, we devised a cost utility model to evaluate the incremental cost-effectiveness ratio of inpatient monitoring. To determine rates of vascular compromise and salvage after digit replantation, we performed a systematic review of the literature through MEDLINE and SCOPUS database searches to identify relevant articles on digital replantation since 1990. Cost-effectiveness was stratified based on the number of digits replanted. RESULTS: Fewer than 9% of replanted digits both experience vascular compromise and are successfully salvaged. Adjusting for this, inpatient monitoring for single-digit and thumb replantation becomes cost-ineffective after 1 day of admission and monitoring for multiple-digit replantation becomes cost-ineffective after 2 days of admission. CONCLUSIONS: In the United States, prolonged admissions for inpatient monitoring quickly become cost-ineffective, especially with relatively low rates of salvage. Surgeons should avoid extended hospitalizations for replant monitoring and should pursue enhanced recovery protocols for replantation, especially considering burgeoning health care costs in the United States. TYPE OF STUDY/LEVEL OF EVIDENCE: Economic/Decision Analysis III.

Clinical Applications of Meshed Multilayered Anatomical Models by Low-Cost Three-Dimensional Printer.

SUMMARY: In recent years, even low-cost fused deposition modeling-type three-dimensional printers can be used to create a three-dimensional model with few errors. The authors devised a method to create a three-dimensional multilayered anatomical model at a lower cost and more easily than with established methods, by using a meshlike structure as the surface layer. Fused deposition modeling-type three-dimensional printers were used, with opaque polylactide filament for material. Using the three-dimensional data-editing software Blender (Blender Foundation, www.blender.org) and Instant Meshes (Jakob et al., https://igl.ethz.ch/projects/instant-meshes/) together, the body surface data were converted into a meshlike structure while retaining its overall shape. The meshed data were printed together with other data (nonmeshed) or printed separately. In each case, the multilayer model in which the layer of the body surface was meshed could be output without any trouble. It was possible to grasp the positional relationship between the body surface and the deep target, and it was clinically useful. The total work time for preparation and processing of three-dimensional data ranged from 1 hour to several hours, depending on the case, but the work time required for converting into a meshlike shape was about 10 minutes in all cases. The filament cost was $2 to $8. In conclusion, the authors devised a method to create a three-dimensional multilayered anatomical model to easily visualize positional relationships within the structure by converting the surface layer into a meshlike structure. This method is easy to adopt, regardless of the available facilities and economic environment, and has broad applications.

A cadaveric assessment of percutaneous trigger finger release with 15° stab knife: its effectiveness and complications.

Percutaneous release of the A1 pulley has been introduced as a therapeutic approach for trigger fingers and is suggested as an effective and safe alternative, where conservative treatments fail. The aim of the current study was to determine if percutaneous release with a 15° stab knife can effectively result in acceptable efficacy and lower complication rate. METHODS: In the present study, the percutaneous release of the A1 pulley was evaluated by percutaneous release using a 15° stab knife in 20 fresh-frozen cadaver hands (10 cadavers). One hundred fingers were finally included in the present study. The success rate of A1 pulley release as well as the complications of this method including digital vascular injury, A2 pulley injury, and superficial flexor tendon injury was evaluated, and finally, the data were analyzed by the SPSS software. RESULTS: The results showed a success rate of 75% for A1 pulley release in four fingers, followed by eleven fingers (90%) and eighty-five fingers (100%). Therefore, the A1 pulley was found to be completely released in eighty-five fingers (100%). Overall, the mean of A1 pulley release for these fingers was determined as 97.9%, indicating that percutaneous trigger finger release can be an effective technique using a 15° stab knife. Furthermore, our findings revealed no significant difference in the amount of A1 pulley release in each of the fingers in the right and left hands. Additionally, 17 fingers developed superficial scrape in flexor tendons, while 83 fingers showed no flexor tendons injuries and no other injuries (i.e., vascular, digital nerve, and A2 pulley injuries). CONCLUSIONS: Percutaneous release of the A1 pulley using a 15° stab knife was contributed to acceptable efficacy and a relatively good safety in the cadaveric model.

Comparative assessment of fingertip replantation in paediatric and adult patients within a single institution.

The purpose of this retrospective study was to compare the outcomes of paediatric and adult fingertip replantation within a single institution. Our retrospective study found no significant difference in the survival rate between the paediatric (10/12) and adult (22/26) groups. At 6 months follow-up, there was no significant difference in sensory recovery between both groups, as measured with Semmes-Weinstein testing, but a significant difference in mean static two-point discrimination testing values between the paediatric (4.0 mm) and adult (6.2 mm) groups. Moreover, the mean time for regaining sensation was faster in paediatric patients (1.3 months) as compared with adult patients (4.1 months). Five children and four adults received erythrocyte transfusion. Paediatric fingertip replantation has similar survival rates, faster and better sensory nerve recovery as compared with adults despite a higher erythrocyte transfusion rate. Although technically demanding, paediatric fingertip replantation is recommended, whenever possible, because of the good outcomes achievable.Level of evidence: IV.

Assessment of sensory outcomes after successful fingertip replantation with or without nerve repair according to amputation level.

BACKGROUND: Good sensory outcome in fingertip replantation is a major part of the success of reconstruction and using the finger. Although some sensorial outcomes have been reported in various series in the literature, there is no controlled study, which demonstrates the anatomical levels where nerve repair should or should not be performed. We aimed to assess sensorial outcomes of fingertip amputations with or without nerve coaptation according to amputation level. METHODS: Between January 2013 and July 2018, patients with Tamai Zone 1 and Zone 2 amputations underwent replantation. The patients were divided two main groups. Patients underwent nerve coaptation were grouped as Group 1, and those coaptation not performed as Group 2. In addition, subgroups were designed according to level of the amputation. Tamai zone 1 amputations were grouped as groups 1a and 2a. Tamai zone 2 amputations were grouped as groups 1b and 2b. The mean age was 30.8 ± 30.8 years in Group 1a, 33.2 ± 12.6 years in Group 1b, 34.1 ± 13.6 years in Group 2a, 34.3 ± 11.1 years in Group 2b. Type of injury were evaluated as clean cut (with knife, saw etc.), moderately crushed, and severely crushed and/or avulsion. In Group 1a, one prominent branch of the nerve was repaired, and in Group 1b, the nerve in both side was repaired. The mean duration of replantation in Group 1a was 1 h and 40 min (1 h and 15 min-2 h), whereas this time was 1 h and 15 min (1 h - 1 h and 35 min) in Group 2a. Then, 2 h 15 min (1 h and 55 min-2 h and 50 min) in Group 1b, and 2 h (1 h and 45-2 h 25 min) in Group 2b. Mean age, type of injury and length of follow-up were statistically compared. Sensorial outcome was evaluated by 2-point discrimination test and the Semmes-Weinstein test. RESULTS: According to the Semmes-Weinstein test, 33% of the fingers tested were normal, 58% had diminished light touch, 8% had diminished protective sensation, and 0% had loss of protective sensation in Group 1a; In Group 1b, these values were 35% (7/20), 55% (11/20), 10% (2/20), 0%; in Group 2a, 38% (6/16), 56% (9/16), 6% (1/16), 0%; in Group 2b, 25% (4/16), 44% (7/16), %25 (4/16), 6% (1/16), respectively Mean static two-point discriminations in Groups 1a, 1b, 2a, and 2b were 4.17 ± 0.58, 4.55 ± 0.69, 4.25 ± 0.68, and 5.9 ± 1.26 mm, respectively. The mean follow-up duration was 24 months in Group 1a, 24 months in Group 1b, 26 months in Group 2a, 21 months in Group 2b. Then, 17 (3 in Group 1a, 6 in Group 1b, 4 in Group 2a, 4 in Group 2b) of the 64 fingers were clean cut amputation, 45 (9 in Group 1a, 14 in Group 1b, 11 in Group 2a, 11 in Group 2b) were moderately crushed amputation, and 2 (1 in Group 2a, 1 in Group 2b) were severely crushed and/or avulsion injury. There was no statistically significant difference between groups 1a and 2a (p = .71). On the other hand, there was a statistically significant increase in sensory outcomes of patients in Group 1b compared to Group 2b (p = .009). There was no statistically significant between the groups in terms of mean age, type of injury and length of follow-up. CONCLUSION: We think that nerve repair does not have a positive effect on sensorial recovery in Tamai Zone 1 amputations, but nerve coaptation should be performed in Tamai Zone 2 replantations if possible for better sensorial result.

Assessment of blood distribution in response to post-surgical steal syndrome: A novel technique based on Thermo-Anatomical Segmentation.

The distal ischemic steal syndrome (ISS) is a complication following the construction of an arteriovenous (A-V) access for hemodialysis. The ability to non-invasively monitor changes in skin microcirculation improves both the diagnosis and treatment of vascular diseases. In this study, we propose a novel technique for evaluating the palms' blood distribution following arteriovenous access, based on thermal imaging. Furthermore, we utilize the thermal images to identify typical recovery patterns of patients that underwent this surgery and show that thermal images taken post-surgery reflect the patient's follow-up status. Thermal photographs were taken by a portable thermal camera from both hands before and after the A-V access surgery, and one month following the surgery, from ten dialysis patients. A novel term "Thermo-Anatomical Segmentation", which enables a functional assessment of palm blood distribution was defined. Based on this segmentation it was shown that the greatest change after surgery was in the most distal region, the fingertips (p < 0.05). In addition, the changes in palm blood distribution in both hands were synchronized, which indicates a bilateral effect. An unsupervised machine learning model revealed two variables that determine the recovery pattern following the surgery: the palms' temperature difference pre- and post-surgery and the post-surgery difference between the treated and untreated hand. Our proposed framework provides a new technique for quantitative assessment of the palm's blood distribution. This technique may improve the clinical treatment of patients with vascular disease, particularly the patient-specific follow-up, in clinics as well as in homecare.

Assessment of Tree-Based Statistical Learning to Estimate Optimal Personalized Treatment Decision Rules for Traumatic Finger Amputations.

Importance: Optimal treatment for traumatic finger amputation is unknown to date. Objective: To use statistical learning methods to estimate evidence-based treatment assignment rules to enhance long-term functional and patient-reported outcomes in patients after traumatic amputation of fingers distal to the metacarpophalangeal joint. Design, Setting, and Participants: This decision analytical model used data from a retrospective cohort study of 338 consenting adult patients who underwent revision amputation or replantation at 19 centers in the United States and Asia from August 1, 2016, to April 12, 2018. Of those, data on 185 patients were included in the primary analysis. Exposures: Treatment with revision amputation or replantation. Main Outcomes and Measures: Outcome measures were hand strength, dexterity, hand-related quality of life, and pain. A tree-based statistical learning method was used to derive clinical decision rules for treatment of traumatic finger amputation. Results: Among 185 study participants (mean [SD] age, 45 [16] years; 156 [84%] male), the median number of fingers amputated per patient was 1 (range, 1-5); 115 amputations (62%) were distal to the proximal interphalangeal joint, and 110 (60%) affected the nondominant hand. On the basis of the tree-based statistical learning estimates, to maximize hand dexterity or to minimize patient-reported pain, replantation was found to be the best strategy. To maximize hand strength, revision amputation was the best strategy for patients with a single-finger amputation but replantation was preferred for all other injury patterns. To maximize patient-reported quality of life, revision amputation was the best approach for patients with dominant hand injuries, and replantation was the best strategy for patients with nondominant hand injuries. Conclusions and Relevance: The findings suggest that the approach to treating traumatic finger amputations varies based on the patient's injury characteristics and functional needs.

Finger Replantation Optimization Study (FRONT): Update on National Trends.

PURPOSE: Traumatic digit amputations have an adverse impact on patients' daily living. Despite experts advocating for digit replantation, studies have shown a continued decrease in rate of replantation. We performed a national-level investigation to examine the recent trend of practice for digital replantation. METHODS: We used the National Inpatient Sample database under the Healthcare Cost and Utilization Project to select adult patients with traumatic digit amputation from 2001 to 2014. We calculated the rate of attempted and rate of successful digit replantation per year, subcategorizing for digit type (thumb or finger) and for hospital type (rural, urban nonteaching, or urban teaching). We also analyzed the pattern of distribution of case volume to each hospital type per year. We used 2 multivariable logistic regression models to investigate patient demographic and hospital characteristics associated with the odds of replantation attempt and success. RESULTS: Among the 14,872 adult patients with a single digit amputation from 2001 to 2014, only 1,670 (11.2%) underwent replantation. The rate of replantation attempt trended down over the years for both thumb and finger injuries at all hospital types, despite increasing proportions of cases being sent to urban teaching hospitals where they were more than twice as likely to undergo replantation. The rate of successful replantation stayed stable for the thumb at 82.9% and increased for fingers from 76.1% to 82.4% over the years. Patients were more likely to undergo replantation if they had private insurance or a higher level of income. Neither hospital case volume nor hospital type was predictive of successful replantation. CONCLUSIONS: Although more single-digit amputations were treated by urban teaching hospitals with higher likelihood to replant, the downward trend in rate of attempt regardless of hospital type demonstrates that concentration of case volume is not the solution to reverse the declining trend. CLINICAL RELEVANCE: Financial aspects of digit replantation need to be considered from both the patients' and the surgeons' perspectives to improve delivery of care for digit replantation.

Skin colour assessment of replanted fingers in digital images and its reliability for the incorporation of images in nursing progress notes.

AIMS AND OBJECTIVES: To determine whether nurses can accurately assess the skin colour of replanted fingers displayed as digital images on a computer screen. BACKGROUND: Colour measurement and clinical diagnostic methods for medical digital images have been studied, but reproducing skin colour on a computer screen remains difficult. DESIGN: The inter-rater reliability of skin colour assessment scores was evaluated. In May 2014, 21 nurses who worked on a trauma ward in Japan participated in testing. METHODS: Six digital images with different skin colours were used. Colours were scored from both digital images and direct patient's observation. The score from a digital image was defined as the test score, and its difference from the direct assessment score as the difference score. Intraclass correlation coefficients were calculated. Nurses' opinions were classified and summarised. RESULTS: The intraclass correlation coefficients for the test scores were fair. Although the intraclass correlation coefficients for the difference scores were poor, they improved to good when three images that might have contributed to poor reliability were excluded. Most nurses stated that it is difficult to assess skin colour in digital images; they did not think it could be a substitute for direct visual assessment. However, most nurses were in favour of including images in nursing progress notes. DISCUSSION: Although the inter-rater reliability was fairly high, the reliability of colour reproduction in digital images as indicated by the difference scores was poor. Nevertheless, nurses expect the incorporation of digital images in nursing progress notes to be useful. This gap between the reliability of digital colour reproduction and nurses' expectations towards it must be addressed. CONCLUSIONS: High inter-rater reliability for digital images in nursing progress notes was not observed. Assessments of future improvements in colour reproduction technologies are required. RELEVANCE TO CLINICAL PRACTICE: Further digitisation and visualisation of nursing records might pose challenges.

A Comparison of Functional Outcomes and Therapeutic Costs: Single-Digit Replantation versus Revision Amputation.

BACKGROUND: The functional outcomes and therapeutic costs between digit replantation and revision amputation have remained controversial. METHODS: A total of 1023 patients with single-digit traumatic amputation or devascularization who underwent successful digit replantation (failure excluded) or revision amputation from January 1, 2013, to January 1, 2016, were included in this study. All cases were subgrouped based on Tamai level of amputation and the injured digit. The clinical outcomes were assessed using the Michigan Hand Outcomes Questionnaire 1 year after the initial operation. The authors also compared the cost of treatment, the duration of hospitalization, and the duration of sick leave between the two treatments. RESULTS: Replantation of small (level I to V), ring (level I to III), and long (level I) fingers showed no functional benefit compared with initial revision amputation. In contrast, replantation of thumb (level I to V), index (level I to V), long (level II to V), and ring (level IV to V) fingers had better outcomes. The cost of replantation was higher and the durations of hospitalization and sick leave of replantation were also longer compared with the revision amputation group. CONCLUSIONS: Single amputated injuries of small (level I to V), ring (level I to III), and long (level I) fingers are a relative contradiction for replantation. Replantation of thumb (level I to V), index (level I to V), long (level II to V), and ring (level IV to V) fingers showed extra benefit compared with revision amputation.

IFSSH scientific committee on skin coverage: 2015 report.

Skin coverage in hand reconstruction is a challenging and vast chapter in hand surgery; covering every aspect of it in a report is simply not feasible. Therefore, this report focuses on a few specific topics. The coverage of anatomical regions like the fingertips is common ground for hand surgeons worldwide, but in the last 10 years, various refinements have been published in order to optimize the reconstruction of this organ. Nevertheless, in many emergency departments, the amputation of badly injured fingertips, including the thumb, remains the preferred treatment. The main focus of this report is to counter this tendency by providing alternatives to surgeons. Large defects in the fingers involving more than one segment, defects in the palm and in the dorsum of the hand are currently debated in international meetings. The use of skin substitutes vs. the use of extremely refined microsurgical procedures vs. classic island flaps has generated animated discussions, which are also influenced by cultural and socioeconomic factors around the world. This report offers the views of six surgeons from four different countries, in the hope of animating discussions and suggesting new approaches.

Quantitative assessment of dynamic control of fingertip forces after pollicization.

Dexterity after finger pollicization (reconstruction to thumb) is critical to functional outcomes. While most tests of hand function evaluate a combination of strength, coordination, and motor control, the Strength-Dexterity (S-D) paradigm focuses on the dynamic control of fingertip forces. We evaluated 10 pollicized and 5 non-pollicized hands from 8 participants ages 4-17 years (2 female, 6 male; 10.6 ± 4.5 years). Participants partially compressed and held an instrumented spring prone to buckling between the thumb and first finger to quantify dynamic control over the direction and magnitude of fingertip forces. They also completed traditional functional tests including grip, lateral pinch, and tripod pinch strength, Box and Blocks, and 9-hole peg test. Six of 10 pollicized hands and all non-pollicized hands had S-D scores comparable to typically developing children. However, dynamical analysis showed that pollicized hands exhibit greater variability in compression force, indicating poorer corrective action. Almost all pollicized hands scored below the normal range for the traditional functional tests. The S-D test Z-scores correlated moderately with Z-scores from the other functional tests (r = 0.54-0.61; p = 0.02-0.04) but more weakly than amongst the other functional measures (r = 0.58-0.83; p = 0.0002-0.02), suggesting that the S-D test captures a different domain of function. A higher incidence of radial absence in the hands with poor S-D scores (3/4 vs. 0/6 in hands with normal S-D scores, p = 0.03) was the only clinical characteristic associated with S-D outcome. Overall, these results suggest that while most pollicized hands can control fingertip forces, the nature of that control is altered.

Comparison of magnification in primary digital nerve repair: literature review, survey of practice trends, and assessment of 90 cadaveric repairs.

PURPOSE: To review published clinical outcomes and current practice trends and to assess the quality of cadaveric digital nerve repairs using either loupe or microscopic magnification. METHODS: Published clinical outcomes of digital nerve repair accounting for magnification level were reviewed. Members of the American Society for Surgery of the Hand were surveyed regarding their current surgical practices. Ninety cadaveric digital nerve repairs were performed by 9 hand surgeons using loupe or microscopic magnification and evaluated by a visual grading scale. Univariate and multivariate analyses were used to evaluate repairs. RESULTS: We examined 6 publications involving 130 repairs with loupes (4-6×) and 255 repairs with microscopes. Univariate analysis revealed no statistically superior clinical outcomes using high-powered loupes (4-6×) versus microscopic magnification, with no data on lower-magnification loupes more commonly used in practice. Survey data indicated that 52% of hand surgeons use microscopes and 48% use loupes, with 78% using 2.5 to 3.5× magnification. Univariate analysis of the cadaveric repairs demonstrated excellent repairs in 60% of microscope repairs versus 29% of loupe repairs. Multivariate analysis determined that microscopic magnification was 3.9 times more likely than loupes to yield an excellent repair. The surgeon, level of training, repair time, and stitches per repair were not significantly related to an excellent repair. CONCLUSIONS: Our study indicated that microscope use produces superior quality digital nerve repair. Approximately half of hand surgeons use loupes in current practice, mostly at low magnification (2.5-3.5×). In this context, a higher level of magnification may be positively correlated with better clinical outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

Diagnosis-Related Groups in Hand Surgery--a comparison of six European countries.

Diagnosis-Related Group (DRG) is a classification system, which groups patients according to their diagnosis and resource consumption. Common hand surgical diagnoses and procedures were processed using national DRG-groupers of six European countries. The upper thresholds of length of stay (LoS) are indicated for every country with the exception of Spain. The mean value in the series was 9.9 days for Germany, 4.5 days for Austria, 10.7 days for Italy, 9.7 days for Sweden and 9.4 days for the United Kingdom (UK). Germany and Austria also have lower thresholds of LoS and the average LoS.Multiple finger replantation presented the highest single case reimbursement in Germany, Austria and the UK (13,825 €, 10,576 € and 9,198 €). Scaphoid non-union had the highest single case reimbursement in Italy (2,676 €), flap coverage of wounds in Spain (5,506 €) and trapeziometacarpal arthritis in Sweden (5,350 €). The mean values for single case reimbursement were as follows: Germany 3,211 €, Austria 2,821 €, Italy 1,947 €, Spain 3,594 €, Sweden 2,403 € and the UK 3,253 €. Ten out of 19 cases showed the highest reimbursement in Spain, followed by the UK (5 cases), Sweden (2 cases), Germany and Austria (1 case each). Applying the case numbers of our clinic to the reimbursement system of each country, total proceeds would be 2.25 million € in Spain, 1.79 million € in Germany as well as the UK, 1.75 million € in Austria, 1.63 million € in Sweden and 1.22 million € in Italy. The consequences of international differences in efficiency and reimbursement are hard to assess as they are influenced by multiple factors that are seldom purely market-driven. However, the consideration of international data for benchmarking and refinement of national compensation systems should be a useful instrument.

Macro- and microcirculatory assessment of cold sensitivity after traumatic finger amputation and microsurgical replantation.

INTRODUCTION: Finger replantations after traumatic amputation are associated with good prognosis and acceptable functional results. However, cold sensitivity is a common and sometimes disabling sequelae after digital replantation. The exact causes of cold intolerance are still unclear; neural as well as vascular mechanisms have been discussed. We examined the macro- and microvascular performance of replanted fingers using high-resolution color-coded sonography for the assessment of skin vessel density of the fingertips as well as nailfold capillary microscopy and laser Doppler anemometry. Subsequently, we correlated these findings with the presence of cold sensitivity of the replanted digits. PATIENTS AND METHODS: Thirty-seven patients (mean age 45 years; range 19-72) with 40 traumatic finger amputations and microsurgical replantations were studied. The mean time interval between amputation and examination was 57.7 months (range 13-95). Macro- and microvascular examination consisted of electronic oscillograms of both arms, photoplethysmograms of all fingers before and after cold test, duplex ultrasound of the finger arteries, high-resolution color-coded sonography of the fingertips and nailfold capillary microscopy with laser Doppler anemometry. RESULTS: Cold sensitivity was present in 33 (83%) of the 40 replanted fingers. Peripheral arterial disease of the upper extremity could be excluded as all oscillograms showed normal findings. A vasospastic reaction after cold test was documented in 74% (30 of 38) of the replanted fingers, compared to 24% (9 of 38) of the contralateral uninjured fingers. Raynaud's phenomenon was restricted to replanted fingers and occurred in 10 of 40 patients (25%). Compared with the contralateral fingertips, reduced skin vessel density was found in 27 of 36 (75%) replants. Nailfold capillary microscopy revealed uncharacteristic morphologic patterns. The capillary flow velocity was 0.28 +/- 0.12 mm/s in the replanted fingers and 0.48 +/- 0.23 mm/s in their unaffected counterparts (P < 0.001). Correlating these findings with the presence of cold intolerance, reduced skin vessel density in the fingertips was significantly different between cold-sensitive replants and those without cold sensitivity (P = 0.05). Reduced skin vessel density was not related to the extent of reconstruction of nerves (P = n.s.), arteries (P = n.s.) and veins (P = n.s.). CONCLUSIONS: Our results do not confirm hypotheses that cold sensitivity after finger replantations is caused by macrovascular problems nor do they support assumptions of a primary capillary microcirculatory failure. Our findings of reduced vessel density point towards diminished thermoregulatory capacities in the fingertips of cold-sensitive replanted digits.