NAIL FOLD CAPILLARY OBSERVATION IN REPLANTEDSEVERED FINGERS

WEI LU, M.D., Ph.D.,* DAPING WANG, M.D., Ph.D., LIJUN LIU, M.D., Ph.D., JIANYI XIONG, M.D., and QIANWEN HE, M.D.

Observation of circulation in replanted severed fingers often relies on the clinical experience of the doctor. This article discusses nail foldcapillary loops (NFCL) observation in the monitoring of the perfusion and circumfluence of replanted digits. In our study, 30 patients with atotal of 39 replanted digits were selected. The WX-9A900 Microcirculation Checkout System (MCS) was adopted to perform evaluation ofcirculation postoperatively. The digits were monitored by clinical examination and MCS at 5- to 7-h intervals for 24 h and then at 2-daysintervals for 14 days. Our results showed that seven digits were observed with inadequate venous circumfluence, and large, long NFCLpresented within 6–12 h postoperatively. Among the replanted digits, two replants resulted in venous crisis that did respond to an arterialinterdiction test, and needed venous grafts. Two digits were observed to have insufficient arterial supply, one of which resulted in arterialcrisis. In this case, NFCL could not be observed and had no response to vein interdiction test. This case needed venous graft to rebuildblood perfusion, and survived eventually. We concluded therefore, that compared with the former studies, NFCL correlates closely with theperfusion and circumfluence of the replanted digits. MCS is noninvasive, reliable, and a direct method in postoperative monitoring of digitreplanted. VVC 2008 Wiley-Liss, Inc. Microsurgery 28:13–16, 2008.

Microsurgical digital replantation has been widely per-

formed since Komatsu and Tamai successfully replanted

a completely amputated thumb.1 Although the surgical

instruments, techniques, and refined indications have

improved, the incidence of vascular crisis in replanted

digits is about 10–30%, and the failure rate about 5–

25%.2–4 Monitoring of the replanted digits continues to

be a challenge. In addition, there is no widely adopted

objective method in the direct observation of the blood

flow in the replanted digits. Nail fold capillary loops

(NFCL) is a mirror of the digit circulation and directly

related to their distal perfusion. NFCL is a type of capil-

lary, located in the proximal end of digit’s nail. NFCL

can easily be observed through the microscope in a digit

nail fold that has blood circulation. In this article, a clini-

cal study was undertaken to evaluate noninvasive moni-

toring of the circulation of postoperative replanted digits.

The device WX-9A900 microcirculation checkout system

(MCS) was adopted to explore the objective changes of

the NFCL in replanted digits. Furthermore, the study

aimed to find abnormal circulation changes as early as

possible so that immediate steps could be taken to save

the replanted digits.

MATERIAL AND METHODS

Thirty cases with a total of 39 severed digits in the

proximal or mid sections of the fingers were selected

using strict protocol. This patient group was composed of

30 patients (nonsmokers) with a total of 39 severed dig-

its. There were 15 male and 15 female patients with an

average age of 24 years (range: 16–32 years). Of these

amputations, 28 digits were severed in the mid section

and 11 in the proximal section. They included 3 thumbs,

7 index fingers, 12 middle fingers, 11 ring fingers, and 6

little finger digits. Replantation process included Kerssler

needle longitudinal interfixation of the severed fingers,

and anastomosis of 1–2 arteries and 2–4 veins. Antibiot-

ics and anticoagulant were implemented postoperatively

to prevent infection and clotting. Detection method and

indexes were as follows: tests were all performed in the

afternoon; examination rooms were quiet and comforta-

ble; and the temperature was 288C. MCS (Fig. 1) was

used for evaluation. Patients could lie down if feeling

weak. One or more sandbags were used to match the

position of the hand and finger. The contralateral side of

the uninjured corresponding finger was checked first, and

then compared with the replanted digit. The test indexes

included: the amount of NFCL (counts/mm), size, shape,

and dynamic of the red blood cells. In addition, if NFCL

showed disorders of the replanted digits, the vein and/or

artery obstruction of the upper extremity were performed

for 30–90 s to observe the dynamic circulation status and

changes of the digits.

WX-9A900 Microcirculation Checkout System

The instruments consisted of three parts: video cap-

ture system, display system, and main computer (Fig. 1).

These were installed in an examination room. The

replanted digit was placed in the fixation bed, clove oil

was painted on the nail fold. The display system could

then show the NFC loops of the digit, while the main

computer analyzed the indexes of the NFC loops

described above.

Department of Traumatic and Hand Surgery, Southern Medical UniversityShenzhen Hospital, Shenzhen, Guangdong 518035, China

*Correspondence to: Wei Lu, M.D., Ph.D., Department of Traumatic andHand Surgery, Southern Medical University Shenzhen Hospital, Shenzhen,Guangdong 518035, China. E-mail: winerlu@hotmail.com

Received 23 March 2007; Accepted 9 August 2007

Published online 2 January 2008 in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/micr.20445

VVC 2008 Wiley-Liss, Inc.

Significance of the Vessel Obstruction

1. Artery obstruction of the upper extremity may stop the

blood inflow of the capillaries, the NFC loops may

become shorter, smaller, and even disappear.

2. The vein obstruction of the upper extremity may stop

the blood outflow of the capillaries, the NFC loops

may become larger, longer, and greater in number.

Detection Steps

1. Check the NFCL of the contralateral side of the corre-

sponding finger.

2. Obstruct the vein and/or artery of the upper extremity

for 30–90 s, record the NFCL’s changes. In our study,

a tourniquet was used in the test for this purpose. The

pressure of vein obstruction was the diastolic pressure

of the patient; artery obstruction was performed by

compressing the radial and ulnar arteries at the wrist.

3. Check the NFCL of the digits replanted.

4. Repeat step 2 on the replanted digits if necessary.

RESULTS

Most cases were without any complication (no inad-

equate venous circumfluence and no insufficient arterial

apply), the NFCL could not be observed after 3-days

postoperatively, but 1–3 small loops/H of NFCL

appeared in the 48–72 h when the vein was blocked. Af-

ter 3 days postoperatively, more and more NFCL ap-

peared and became increasingly bigger. NFCL recovered

to normal in size and number within a week (Fig. 2,

Table 1).

In the cases with insufficient venous perfusion, many

large, long NFCL appeared within 12 h (3–12 loops/

mm), the NFCL increased and enlarged when the vein

was blocked. When the artery was blocked, the NFCL

became thinner but the NFCL number remained the

same. In cases with venous crisis, the NFCL remained

unchanged whether the artery or vein was blocked (Fig. 3,

Table 1).

In the cases with insufficient arterial apply, no NFCL

appeared and 1–3 loops/H presented when the vein was

blocked. However, in cases of arterial crisis, there was no

response in any form.

In the cases with venous (three digits) and arterial cri-

sis (one digit), reexploration was performed, and venous

graft was used to rebuilt the circulation. Finally, one digit

with arterial crisis was partially necrosed, while the

others survived.

CASE REPORTS

Case 1

This case involved a 22-year-old female with her

middle finger severed at the middle phalangeal bone.

The digit replantation was performed 2 h after injury.

Interfixation of the bone was performed with a mini

plate and two arteries and three veins were rebuilt. The

digit had been showing warm, normal capillary refill

time postoperatively. The NFCL could not be observed

within 48-h postoperation, but three small NFCL

appeared in 54 h when the vein was blocked. At 3 days

after replantation, the NFCL of the digit replanted

became increasingly bigger. It recovered to normal size

and number as compared with the contralateral digit

within 6 days.

Case 2

An 18-year-old man sustained a totally severed left

thumb at the interphalangeal joint. During the replanta-

tion process, Kerssler needle longitudinal interfixation

was done, and two arteries and two veins were anasto-

mosed. General routine of anticoagulation was performed

postoperatively. At 6 h after the replantation, the re-

planted thumb was found to have an inadequate venous

circumfluence: swelling, cyanosis, faster capillary filling

time, and the NFCL check showed longer, larger NFCL

than the contralateral thumb, and greater in number (8/

mm to 6/mm). When the artery of the replanted thumb

was blocked, the NFCL became smaller and shorter with

same NFCL number. So we judged the thumb to be the

incompletely obstructed. At 2 h after the anticoagulant

drug and other measurement was used, the appearance of

the thumb remained same, but NFCL showed no response

to arterial interdiction test, which indicated venous crisis

and complete vein obstruction. A reexploration of the

replanted thumb was performed, the thrombosis was

found and removed, and venous graft was used. The digit

ultimately survived.

Figure 1. Manipulation platform for NFCL checking.

14 Lu et al.

Microsurgery DOI 10.1002/micr

DISCUSSION

Until now, the postoperative monitoring of digit

replants has relied primarily on the surgeon’s experience.

Most of the current objective methods of digit monitoring

are indirect: these instruments estimate the circulation

status via observing the skin temperature, oxygen tension,

and other indirect indexes.5,6 In this article, we applied

MCS to directly observe the NFCL. We hoped this could

be a direct method to decrease the failure of the digit

replantation.

NFCL is a type of capillary located in the proximal

end of digit’s nail. NFCL can easily be observed through

the microscope in a digit nail fold that has blood circula-

tion. In addition, NFCL’s status can directly and dynami-

cally reflect the current blood circulation status of the

replanted digits.7,8 Therefore, this clinical study was

undertaken to evaluate the feasibility for the NFCL obser-

vation in the judgment of the circulation status in

replanted digits. In our earlier study,9,10 we checked

NFCL in normal digits and in random cases of replanted

Figure 3. Shows normal NFCL (A), and insufficient venous perfusion (B): many large, long NFCL appeared within 12 h (3–12 loops/mm).

Table 1. The Appearance of the NFCL in Digits Replanted

Time

Normal surviving digits Digits with vessel disorder

Counts Shapes Flow speed Counts Shapes Flow speed

6 h — — — 0–14 Much slow

12 h — — — 8–14 Much slow

1 d — Very slow 7–16 — —

2 d 2–5 Slow — — —

5 d 3–7 Faster — — —

7 d 9–14 Normal — — —

14 d 9–16 Normal — — —

Figure 2. NFCL appearance: (1d) 1 day after replantation, no NFCL was observed; (3d) 3 days after replantation, a small number of NFCL

could be discriminated; (5d) and (7d): 5 days and a week later postoperatively, NFCL were increasingly longer and larger to normal.

NFCL Observation in Replanted Severed Fingers 15

Microsurgery DOI 10.1002/micr

digits. We concluded that NFCL observation was an

objective way of monitoring the digit’s blood circulation.

However, the random selected cases made it difficult for

statistical analysis of the results. In this study, we

designed a prospective observational study. The section

of the severed digits, and the sex and age of the patients

were strictly stipulated, and the indexes were redesigned.

CONCLUSION

We found that in cases without any complication,

the NFCL could appear within 2-days postoperatively,

as opposed to 3 days observed in our early findings.

This result showed that blocking the arterial or/and ve-

nous flow appropriately can help to diagnose the digits’

earlier blood flow disorder more promptly. As a result,

most of the digits with insufficient blood flow were

observed promptly and treated with medication. Three

digits with vessel crisis underwent venous graft, and

only part of one digit became necrosed (survival rate:

>98%). We conclude that NFCL observation can be an

effective and useful method in the early diagnosis and

for the future management of blood flow abnormality in

replanted digits.

REFERENCES

1. Komatsu SA, Tamai S. Successful replantation of a completely cut-off thumb: Case report. Plast Reconstr Surg 1968;42:374–377.

2. Masuhara K, Tamai S, Fukunishi H, Obama K, Komatsu S. Experi-ence with reanastomosis of the amputated thumb. Seikei Geka1967;18:403–404.

3. Dec W. A meta-analysis of success rates for digit replantation. TechHand Up Extrem Surg 2006;10:124–129.

4. Isogai N, Cooley BG, Kamiishi H. Clinical outcome of digitalreplantation using the fibrin glue-assisted microvascular anastomosistechnique. J Hand Surg [Br] 1996;21:573–575.

5. Kiyoshige Y. Effect of hyperbaric oxygen therapy as a monitoringtechnique for digital replantation survival. J Reconstr Microsurg1999;15:327–330.

6. Ad El DD, Harper A, Hoffman LA. Digital replantation teachingmodel in rats. Microsurgery 2000;20:42–46.

7. Hasegawa K, Pereira BP, Pho RW. The microvasculature of the nailbed, nail matrix, and nail fold of a normal human fingertip. J HandSurg [Am] 2001;26:283–290.

8. Terreri MT, Andrade LE, Puccinelli ML, Hilario MO, Goldenberg J.

Nail fold capillaroscopy: Normal findings in children and adoles-

cents. Semin Arthritis Rheum 1999;29:36–42.9. Lu W, Liu QM, Chen X. The observation of the nail fold capillary

loops change in normal people with digit vessel blocked. J ChinMicrocircula 2000;4:109–110.

10. Lu W, Xiao JD, Chen X. The application of the nail fold capillary

in the observation of replanted severed fingers. J Chin Microcircula2003;7:37–38.

16 Lu et al.

Microsurgery DOI 10.1002/micr