ORIGINAL ARTICLE

Sonographic assessment of carpal tunnel syndrome in rheumatoidarthritis: prevalence and correlation with disease activity

Omer Karadag • Umut Kalyoncu • Ali Akdogan • Yesim Sucullu Karadag •

Sule Apras Bilgen • Senay Ozbakır • Emilio Filippucci • Sedat Kiraz •

Ihsan Ertenli • Walter Grassi • Meral Calguneri

Received: 15 December 2010 / Accepted: 8 May 2011 / Published online: 24 May 2011

� Springer-Verlag 2011

Abstract Carpal tunnel syndrome (CTS) is one of the

most frequent extra-articular manifestations of rheumatoid

arthritis (RA). High frequency ultrasonography (US) is a

sensitive and specific method in diagnosis of CTS. This

study is aimed to: firstly assess diameter frequency of

CTS in RA with US and compare with a control group;

secondly, investigate relationship of CTS with disease

activity. One hundred consecutive RA patients (women/

men: 78/22) fulfilling ACR 1987 RA criteria and 45

healthy controls (women/control: 34/11) were enrolled

into study. Disease activity parameters, RA and CTS

patient global assessment and health assessment ques-

tionnaire (HAQ-DI) were recorded. Both patient and

control group were questioned about secondary causes of

CTS, and Katz hand diagram, Boston CTS questionnaire

and Phalen ve Tinel tests were applied once for each

hand. Wrist joint and carpal tunnel were assessed with US

grey scale and power Doppler US, then cross-sectional

area of median nerve (CSA) was calculated. Patients with

median nerve CSA between 10.0 and 13.0 mm2 were

evaluated with electromyography (EMG). CTS was

diagnosed if CSA of median nerve [13.0 mm2 or CTS

was shown with NCS. Although there was no difference

between RA patients and controls in age, sex, history of

DM (?) and goitre, CTS was more frequent in RA group

(respectively, 17.0% vs. 4.4%, P = 0.038). In RA group

with CTS, age, history of DM, disease duration, HAQ-DI

score, CTS patient global score, Boston symptom severity

and functional status scores were elevated compared to

without CTS [respectively, 57 (36–73) vs. 50 (24–76),

P = 0.041; 35.3% vs. 6.0%, P \ 0.001; 108 (12–396)

months vs. 72 (6–360) months, P = 0.036; 1.93 (0.75–

2.87) vs. 1.125 (0–2.75), P = 0.013; 52 (1–97) vs. 25

(0–91), P = 0.001; 2.81 (1.18–4.17) vs. 2.0 (1.0–4.01),

P = 0.01; 3.37 (1.37–5.0) vs. 2.25 (1.0–5.0), P = 0.008].

No difference was found between CTS (?) and (-) RA

patients in acute phase reactants, disease activity and US

findings (P [ 0.05). Sensitivity of Katz hand diagram was

higher than Tinel and Phalen tests (respectively, 100,

60.0, 66.7%). Boston symptom and functional scores of

RA patients with CTS diagnosed by EMG were increased

than patients CTS (-) by EMG [respectively, 3.05

(1.90–4.27) vs. 1.55 (1.0–2.90), P = 0.002; 3.25 (1.73–

3.82) vs. 1.12 (1.0–2.10), P = 0.008]. CTS frequency in

RA was found higher than normal population, especially

in patients with additional risk factors of CTS. There was

no relationship between CTS and disease activity.

CTS group had long disease duration and worse func-

tional status. CTS could be a result of the chronic course

in RA. In patient with CSA between 10 and 13 mm2,

Boston CTS questionnaire might give additional idea

about CTS.

Keywords Rheumatoid arthritis � Carpal tunnel

syndrome � Ultrasonography � Electromyography �Boston carpal tunnel syndrome questionnaire

O. Karadag (&) � U. Kalyoncu � A. Akdogan �S. A. Bilgen � S. Ozbakır � S. Kiraz � I. Ertenli � M. Calguneri

Department of Internal Medicine Unit of Rheumatology,

Hacettepe University, Incesu Caddesi No: 72/2, Ankara, Turkey

e-mail: omerk@hacettepe.edu.tr

Y. S. Karadag

Ankara Numune Education and Research Hospital 1st Neurology

Clinic, Ankara, Turkey

E. Filippucci � W. Grassi

Rheumatology Department, Universita Politecnica della Marche,

Ancona, Italy

123

Rheumatol Int (2012) 32:2313–2319

DOI 10.1007/s00296-011-1957-0

Introduction

Carpal tunnel syndrome (CTS) is one of the most frequent

extra-articular manifestations of rheumatoid arthritis (RA)

[1]. Nerve conduction studies (NCS) are the standard

diagnostic test for CTS [2]. High frequency ultrasonogra-

phy (US) is a non-invasive, cheaper, sensitive (89%) and

specific (83%) method in diagnosis of CTS [3, 4]. More-

over, US gives us opportunity to determine median nerve

and carpal tunnel pathologies [5]. Additionally, a CTS

severity algorithm based on the cross-sectional area (CSA)

of median nerve at proximal inlet of carpal tunnel has been

suggested (CSA 7.0–10.0 mm2: normal, 10.0–13.0 mm2:

mild, 13.0–15.0 mm2: moderate,[15.0 mm2: severe CTS)

[6]. The usefulness of this algorithm in RA was shown [7].

Additionally, RA patients with CSA between 10 and

13 mm2 are recommended to further evaluation with NCS.

But we could not find a US study investigating relationship

of disease activity with CTS in English literature. This

study was aimed to: firstly assess the prevalence of CTS

diagnosed by US in RA patients and healthy subjects

secondly, investigate relationship between CTS and disease

activity in RA.

Patients and methods

Patients

The study is approved by local ethics committee of

Hacettepe University. One hundred consecutive RA

patients (women/men: 78/22) fulfilling ACR 1987 RA

criteria and seen between May and November 2008 and 45

healthy control (women/men: 34/11) from check-up unit

were enrolled into study.

Clinical examinations

Demographic characteristics, swollen and tender joint

count, acute phase reactants [erythrocyte sedimentation

rate, C-reactive protein, complete blood count], RA patient

global assessment visual analogue scale (VAS 0–100 mm),

Health assessment questionnaire disability index (HAQ-

DI), disease activity score (DAS 28) and treatment

modalities were evaluated. Both patient and control group

were questioned about secondary causes of CTS [diabetes

mellitus (DM) and goitre]. CTS patient global score (VAS

0–100 mm), Katz hand diagram [8], Levine Boston CTS

questionnaire (BQ) [9], Phalen ve Tinel tests [10] were

applied once for each hand.

The BQ evaluates CTS in two subjects: Symptom

severity (BQ-sympt.) consisting of 11-items and functional

status (BQ-funct.) testing 8-items. A Turkish version of BQ

validated by Sezgin et al. [11] was used. The BQ was

presented in multiple-choice format, and scores were

assigned from 1 point (mildest) to 5 points (most severe).

Each score was calculated as the mean of the responses of

the individual items. Patients were divided into 4 groups

according to their mean score: extreme (4.1–5.0 points),

severe (3.1–4.0 points), moderate (2.1–3.0 points), mild

(1.1–2.0) points.

Ultrasonography

Sonographic evaluation of wrist joint and carpal tunnel

was performed by a rheumatologist (OK) blinded to the

physical and electrophysiologic findings of the subjects.

A MyLab 70 US system (Esaote Biomedica–Genoa, Italy)

equipped with a broadband 6–18-MHz linear transducer

was used. Patients were seated in a comfortable position

facing the sonographer, with the forearm resting on the bed

and fingers semi-flexed.

Wrist joint cavity widening and intra-articular power

Doppler signal (PDS) were assessed using a multi-planar

dorsal examination and adopting a semi-quantitative scor-

ing system from 0 to 3 (0: normal, 1: mild, 2: moderate, 3:

marked) [12, 13]. The median nerve was located superficial

to the echogenic flexor tendons. The full course of median

nerve in the carpal tunnel was assessed in longitudinal and

transverse planes. The main hallmark of tenosynovitis is

irregularities of tendon margins and presence of fluid in the

tendon’s sheath. The cross-sectional area of the median

nerve was measured at the proximal inlet of the carpal

tunnel using the pisiform bone as landmark by tracing a

continuous line within the hyperechogenicity boundary of

the nerve. No additional compression was applied on the

tissues under examination other than the weight of

the probe to avoid causing any artificial nerve deformity.

The cross-sectional area was measured three times, and the

mean value was used for further analysis. Each 10th patient

was asked to return within 24 h for assessing intra-observer

US reliability. A total of 9 CTS patients were assessed for

this purpose.

Nerve conduction studies

Hammer HB et al. [7] showed 10% of RA patients without

CTS symptoms had CSA areas reported in patients with

mild idiopathic CTS. And NCS are recommended for

patients with CSA 10.0–13.0 mm2.

According to this recommendation, electro-diagnostic

studies were carried out for all subjects with CSA between

10.0 and 13.0 mm2 according to the protocol proposed by

the American Academy of Neurology [14]. All testings

were done in the same room and in room temperature

conditions using Nihon Kohden 4 ME 8 elektrode entrance

2314 Rheumatol Int (2012) 32:2313–2319

123

4 record channel device by a neurologist (YSK) blinded to

clinical findings. Skin temperature on the hand was mea-

sured and maintained between 32.0 and 34.0�C. All par-

ticipants underwent median and ulnar nerve sensorimotor

NCS. Standard techniques of supramaximal percutaneous

stimulation with a constant current stimulator and surface

recording were used for NCSs. A ground electrode was

placed on the dorsum of the hand. The active electrode was

located over the thenar eminence (abductor pollicis brevis

muscle) for the median nerve and over the hypothenar

eminence (abductor digiti minimi) for ulnar nerve to record

compound muscle action potentials. The reference elec-

trode was placed over the first or fifth metacarpophalangeal

joint. The median and ulnar nerves were stimulated at the

wrist and elbow (antecubital region for median nerve, ulnar

fossa for ulnar nerve) at a distance of 8 cm from the wrist

to the active electrode. Sensory responses were obtained

antidromically.

Ring electrodes were used to obtain sensory nerve action

potentials. Electrodes were placed over the second finger

for the median nerve and fifth finger for the ulnar nerve.

The active recording electrode was placed more proxi-

mally, closest to the stimulator. The median and ulnar

nerves were stimulated at the wrist and elbow (antecubital

region for median nerve, ulnar fossa for ulnar nerve). The

severity of electrophysiological CTS impairment was

assessed by a previously reported neurophysiological

classification into 5 groups [15].

• Negative: nerve conduction studies are normal, no

electrophysiological evidence of CTS.

• Mild: slowing of the median sensory nerve conduction

velocity and normal distal motor latency.

• Moderate: slowing of the median sensory nerve con-

duction velocity and prolonged distal motor latency.

• Severe: absence of sensory response and prolonged

distal motor latency.

• Extreme: absence of motor and sensory responses.

The diagnosis of CTS was accepted in two situations:

1. CTS symptomatology ? CSA of median nerve

[13 mm2

2. CTS diagnosed with NCS in wrist with CSA

10.0–13.0 mm2

CTS Statistical analysis

Statistical analysis was performed with SPSS 11.0. Data

are presented as mean ± SD or median (range). CTS fre-

quency of RA patients was compared with control group.

Correlation between CSA of median nerve and age, disease

duration and CTS symptom duration was investigated.

Differences between CTS (?) and (-) RA groups

regarding age, sex, disease duration, RA treatments were

evaluated. Comparison of RA patients and controls for

numeric data was done with student t-test (for parametric

data) or Mann–Whitney U-test (for non-parametric data),

for nominal data with chi-square test. Correlation analysis

was made with Pearson’s or Sperman correlation test. In

the comparison of groups, P B 0.05 was accepted as

significant.

Results

One hundred consecutive RA patients (M/F: 22/78) were

recruited into the study. Patients mean age was

50.9 ± 12.6 years (range 24–76), and mean disease dura-

tion was 96.6 ± 80.3 month (Table 1). Demographic and

clinical findings of RA patients were shown in Table 1.

All of the patients were on DMARD treatment. Patients’

treatment protocols and per cents are shown in Table 3. Fif-

teen per cent of patients were on treatment of anti-tumour

necrosis factor a (TNF-a) agent ? DMARD combination.

Mean daily prednisolone dose was 1.43 ± 1.36 mg.

Seventy-one per cent of RA patients were rheumatoid

factor (RF) positive, and 69% of patients were anti-CCP

(cyclic citrulinnated peptide) positive. Sixty-two per cent

Table 1 Demographic and clinical findings of RA patients

Age, years (mean ± SD) 50.9 ± 12.6

Disease duration, month 96.6 ± 80.3

0–2 year, % 18

2–10 year, % 48

[10 year, % 34

Sex (female/male) 78/22

Diabetes mellitus, % 11

Hypothyroidism

Euthyroidism with treatment, % 16

Extra-articular involvement

Rheumatoid nodule, % 11

Pulmonary involvement, % 8

Treatment protocols

Mono-therapy 0

Double combination 15

Triple combination 57

Four agent combination 11

Anti-TNF ?DMARD combination 15

Anti-TNFa agent, % 15

Infliximab, % 5

Etanercept, % 3

Adalimumab, % 7

Combination treatments are consist of (hydroxychloroquine, metot-

rexate, sulphasalasine, leflunomide)

Rheumatol Int (2012) 32:2313–2319 2315

123

of patients had moderate or severe RA activity (Table 2.).

Laboratory, disease activity, damage and US findings of

RA patients are shown in Table 2.

Comparison of RA patients and controls

Although there was no difference between RA patients and

controls in age, sex, body mass index, history of DM (?)

and goitre, CTS was more frequent in RA group (respec-

tively, 17.0% vs. 4.4%, P = 0.038) (Table 3). Boston CTS

scores were higher in RA group.

CTS in RA patients

CTS was found in 30 of 200 wrists in RA group (15%) [12

mild (6%), 10 moderate (5%), 8 severe (4%)]. Twelve

patients had bilateral CTS. There were median nerve

abnormalities in 19 wrist (9.5%) [15 (7.5%) bifid median

nerve, 4 (2%) persistent median artery].

Comparison of RA patients with and without CTS

groups

In RA group with CTS age, history of DM, disease dura-

tion, HAQ-DI score, CTS patient global score, Boston

symptom severity and functional status scores were ele-

vated compared to without CTS group (Table 4). CTS was

found in RA patients with secondary causes, respectively,

in 6 of 11 (54.5%) patients with DM, in 3 of 16 (18.8%)

patients with goitre, and in 7 of 20 (35%) patients with DM

and/or goitre. Although patients with CTS were elder and

had longer disease duration and higher HAQ-DI and Bos-

ton scores, no difference was found between groups in

acute phase reactants, extra-articular manifestations (nod-

ules, pulmonary involvement) and disease activity findings

(P [ 0.05) (Table 4). In sonographic evaluation, there was

no difference between the groups regarding joint cavity

widening, power Doppler signal increase, flexor tenosyn-

ovitis frequencies (P [ 0.05).

In the assessment of sensitivities of tests in CTS, sen-

sitivity of Katz hand diagram was found higher than Tinel

and Phalen tests (respectively, 100, 60.0, 66.7%).

There was no correlation between CSA of median nerve

and demographic and disease activity markers except for

age (r2 = 0.233, P = 0.02) and body mass index

(r2 = 220, P = 0.028).

Intra-observer variability of CSA of median nerve was

found as kappa score = 0.94.

In subgroup analysis, 31 wrists of 20 RA patients (CSA

between 10 and 13 mm2) were assessed with NCS. Twelve

wrists (38.7%) of 8 patients had CTS. There was no difference

between these subgroups (CTS (?) and (-) regarding age,

RA disease duration, DAS 28, acute phase reactants, HAQ-

DI, body mass index, CTS symptom score, CSA except for

Boston symptom severity and functional status scores

[respectively, 3.05 (1.90–4.27) vs. 1.55 (1.0–2.90),

P = 0.002; 3.25 (1.73–3.82) vs. 1.12 (1.0–2.10), P = 0.008].

Discussion

This is the first study assessing CTS frequency in RA with

high frequency US. CTS frequency was found as 17% in

RA. Twelve per cent of patients had bilateral CTS. This

frequency is higher than the previous studies. Carmona

Table 2 Laboratory, disease activity, damage and US findings of RA

patients

Characteristics

Tender joint count 2 (0–11)

Swollen joint count 1 (0–8)

RA patient global score,a 39.2 ± 19.5

ESR, mm/h 17 (2–86)

CRP, mg/L 7 (1–17.6)

Rheumatoid factor (RF) positivity, %b 71

Anti-CCP antibody positivity, %b 69

DAS 28 3.56 ± 1.15

Remission (\2.6), % 23

Mild activity (2.6–3.2), % 15

Moderate (3.2–5.1), % 52

Active (C5.1), % 10

Complete blood count

Leucocyte,/mm3 7,400 ± 2,700

Haemoglobin, g/dL 12.9 ± 1.5

Haematocrite, % 37.7 ± 4.0

Thrombocyte, 103/mm3 284 ± 79

HAQ-DI 1.25 ± 0.84

Arthritis in physical examination, n (%) 64 (32%)

Joint cavity widening with US

0(normal), n (%) 70 (35%)

1 (mild), n (%) 85 (42.5%)

2 (moderate, n (%) 31 (15.5%)

3 (severe), n (%) 14 (7%)

Power Doppler signal increase

0 (No signal), n (%) 145 (72.5%)

1 (mild), n (%) 41 (21.5%)

2 (moderate), n (%) 11 (5.5%)

3 (severe), n (%) 3 (1.5%)

Flexor tenosynovitis, n (%) 35/200 (17.5%)

Values are labelled as mean ± SD or median (minimum maximum),a Visual analogue scale (0–100 mm), b results in administrated

patients, ESR Erythtrocyte sedimentation rate, CRP C-reactive pro-

tein, CCP Cyclic citrullinated peptide, DAS 28 Disease activity score,

HAQ-DI Health assessment questionnaire disability index

2316 Rheumatol Int (2012) 32:2313–2319

123

et al. [16] had found CTS frequency 10.7%. Symptom-

atology of CTS plus Phalen and/or Tinel test positivity or

previous diagnosis with NCS or previous surgery was

accepted as CTS diagnosis. In nerve conduction studies

detecting neuropathies in patients with RA, CTS frequency

was found as 10.1 and 12.5% [17, 18]. Although NCS is the

mostly accepted method in assessing CTS, it is expensive,

time-consuming, partly invasive and could not be reachable

in centres [19]. It does not give information about aetiology

of CTS and structures in carpal tunnel. Moreover, in

Table 3 Comparison of CTS risk factors and findings between RA patients and controls

RA patients (n = 100) Control group (n = 45) P

Age, years 50.9 ± 12.6 46.7 ± 12.6 NS

Sex, (female/male) 78/22 34/11 NS

Diabetes mellitus (?), n (%) 11 (11%) 5 (11.1%) NS

Goitre, n (%) 16 (16%) 4 (8.8%) NS

CTS (?), n (%) 17 (17%) 2 (4.4%) 0.038

Mild CTS 12 wrist 0 wrist

Moderate CTS 10 wrist 2 wrist

Severe CTS 8 wrist 0 wrist

Body mass index, kg/m2 26.65 ± 5.25 27.41 ± 4.66 NS

CTS global assessment, VAS 31.64 ± 27.4 23.48 ± 28.67 NS

CTS symptom duration, month 55.53 ± 43.50 37.57 ± 52.60 NS

CSA of median nerve, mm2 9.72 ± 2.18 9.51 ± 1.6 NS

Boston symptom severity score 2.19 ± 0.92 1.51 ± 0.72 \0.001

Boston functional status 2.55 ± 1.23 1.48 ± 0.84 \0.001

Values are labelled as mean ± SD, NS non significant, Global assessment 0–100 mm visual analogue scale

Table 4 Comparison of demographic and disease activity findings of CTS (?) and (-) RA patients

CTS (?) patients (n = 17) CTS (-) patients (n = 83)

Age, years 57 (36–73) 50 (24–76) 0.041

Sex, (female/male) 13/4 65/18 NS

Diabetes mellitus (?), n (%) 6 (35.3%) 5 (6.0%) \0.001

Goitre, n (%) 3 (17.6%) 13 (15.7%) NS

Disease duration, month 108 (12–396) 72 (6–360) 0.036

Body mass index, kg/m2 28.6 (20.4–42.9) 26.2 (16.2–40.8) NS

Tender joint count 2 (0–11) 2 (0–10) NS

Swollen joint count 1 (0–8) 1 (0–8) NS

RA patient global score 40 (20–80) 40 (0–90) NS

DAS 28 3.61 (2.03–5.20) 3.41 (0.63–6.26) NS

HAQ-DI 1.93 (0.75–2.87) 1.125 (0–2.75) 0.013

ESR, mm/sa 16.5 (6–42) 19 (2–86) NS

CRP, mg/dL 0.65 (0.11–1.50) 0.76 (0.1–17.6) NS

CTS global assessment, VAS 52 (1–97) 25 (0–91) 0.001

CTS symptom duration, month 42 (0–120) 40 (0–180) NS

CSA of median nerve, mm2 13.0 (9.0–15.3) 9 (6.0–12.0) \0.001

Joint cavity wideninga 1 (0–3) 1 (0–3) NS

PDS increasea 0 (0–2) 0 (0–3) NS

Flexor tenosynovitis 8/30 (26.7%) 27/170 (15.8%) NS

Boston symptom severity score 2.81 (1.18–4.17) 2.02 (1.0–4.01) 0.01

Boston functional status 3.37 (1.37–5.0) 2.25 (1.0–5.0) 0.008

Values are labelled as median (minimum–maximum, NS non significance, Global assessment 0–100 mm visual analogue scale, HAQ-DI Health

assessment questionnaire disability index, a 0: normal, 1: mild, 2: moderate, 3: marked joint cavity widening/or signal increase, Boston scores.

1–5

Rheumatol Int (2012) 32:2313–2319 2317

123

13–27% CTS patients, NCS is normal and additional

imaging methods are required [10]. It was shown that US

could be used in these patients [20].

High frequency US can assess structures in carpal tunnel

in addition to median nerve [5]. In CTS, enlargement of

median nerve occurs at the proximal site of compression.

Standardization of measurement of CSA was analysed, and

it was found 89% sensitive and 83% specific in detecting

CTS [3]. An algorithm evaluating CTS severity based on

CSA of median nerve was suggested [6].

It was shown that in patients with arthritis, CSA of

median nerve was increased [21]. The same study group

found CSA of median nerve in patients without CTS was

similar to healthy subjects [7]. But 10% of patients without

CTS, measures could overlap with that of mild CTS

(10.0–13.0 mm2). Additional NCS is recommended to this

subgroup.

Wrist arthritis and flexor tenosynovitis could bring

additional risk in CTS development [22]. High frequency

US could detect possible causes of CTS like flexor teno-

synovitis, median nerve abnormalities, persistent median

artery and accessory muscle [5]. We assessed joint cavity

widening and PDS increase in wrist joint. We could not

find a difference between the CTS (?) and (-) RA patients

in findings of arthritis, tenosynovitis and carpal tunnel

pathologies.

Rheumatoid arthritis disease activity and damage were

evaluated with tender and swollen joint count, patient

global assessment, DAS 28, acute phase reactants and

HAQ-DI. Whilst there was no difference in disease activity

parameters, disease duration and HAQ-DI were higher in

CTS group (P = 0.013). Agarwal et al. [17] found no

association with CTS and disease activity, duration and

HAQ score. Our patients had higher disease duration.

Longer disease duration could result with worse functional

status (high HAQ-DI). CTS might be partly reflects worse

functional status. Disease activity findings and acute phase

reactants reflect condition of a distinct period of disease.

Since there was no relation between disease activity and

patients with CTS had higher disease duration, worse

functional capacity might suggest CTS could develop in

chronic course.

RA patients and control group were similar in age, body

mass index, CTS risk factors. However, CTS frequency

was higher in RA (17% vs. 4.5%, P = 0.036). In subgroup

analysis 6 of 11 (54.5%) DM patients there were CTS. RA

patients with additional CTS risk factors (DM, goitre, older

age, obesity) should be carefully evaluated about CTS.

Weight loss and life style changes could suggest to these

patients to prevent CTS.

There are additional tests and questionnaires widely

used in CTS like (Tinel and Phalen tests, Katz hand dia-

gram and Boston CTS questionnaire [8, 15]. But we could

not find a study that had used these tests in RA. In our

study, sensitivity and specificity of Katz hand diagram was

higher than Tinel and Phalen tests. Also Katz hand diagram

is simple and gives opportunity to better localization of

symptoms. Thus, Katz hand diagram could be a screening

test in assessing CTS in RA patients.

Boston CTS questionnaire is widely used in evaluating

treatment response in CTS. Both symptom severity and

functional status scores were higher in CTS group. Another

aim of our study was to determine patients with CSA

10–13 mm2. Boston scores were found higher in CTS (?)

subgroup. Although NCS is suggested to this subgroup,

higher Boston CTS scores might give idea about CTS in

this group.

Limitations

US do not give information about peripheral neuropathy,

radiculopathy and other entrapment neuropathies.

Conclusion

CTS frequency in RA is found higher than normal popu-

lation, especially in patients with additional risk factors of

CTS. There was no relationship between CTS and disease

activity, and CTS group had long disease duration and

worse functional status. CTS could be a result of the

chronic course in RA. In patients with CSA between 10 and

13 mm2, Boston CTS questionnaire might give additional

idea about CTS.

Conflicts of interest none.

References

1. Young A, Koduri G (2007) Extra-articular manifestations and

complications of rheumatoid arthritis. Best Pract Res Clin

Rheumatol 21(5):907–927

2. Jablecki CK, Andary MT, Floeter MK, Miller RG, Quartly CA,

Vennix MJ, Wilson JR; American Association of Electrodiag-

nostic Medicine; American Academy of Neurology; American

Academy of Physical Medicine and Rehabilitation (2002) Prac-

tice parameter: Electrodiagnostic studies in carpal tunnel syn-

drome. Report of the American Association of Electrodiagnostic

Medicine, American Academy of Neurology, and the American

Academy of Physical Medicine and Rehabilitation. Neurology

58(11):1589–1592

3. Wong SM, Griffith JF, Hui AC, Tang A, Wong KS (2002) Dis-

criminatory sonographic criteria for the diagnosis of carpal tunnel

syndrome. Arthritis Rheum 46(7):1914–1921

4. McQueen FM, Ostergaard M (2007) Established rheumatoid

arthritis–new imaging modalities. Best Pract Res Clin Rheumatol

21(5):841–856

5. Filippucci E, Iagnocco A, Meenagh G, Riente L, Delle Sedie A,

Bombardieri S, Valesini G, Grassi W (2006) Ultrasound imaging

for the rheumatologist II. Ultrasonography of the hand and wrist.

Clin Exp Rheumatol 24(2):118–122

2318 Rheumatol Int (2012) 32:2313–2319

123

6. El Miedany YM, Aty SA, Ashour S (2004) Ultrasonography

versus nerve conduction study in patients with carpal tunnel

syndrome: substantive or complementary tests? Rheumatology

(Oxford) 43(7):887–895

7. Hammer HB, Haavardsholm EA, Kvien TK (2007) Ultrasono-

graphic measurement of the median nerve in patients with

rheumatoid arthritis without symptoms or signs of carpal tunnel

syndrome. Ann Rheum Dis 66(6):825–827

8. D’Arcy CA, McGee S (2000) The rational clinical examination.

Does this patient have carpal tunnel syndrome? JAMA

283(23):3110–3117

9. Levine DW, Simmons BP, Koris MJ, Daltroy LH, Hohl GG,

Fossel AH, Katz JN (1993) A self-administered questionnaire for

the assessment of severity of symptoms and functional status in

carpal tunnel syndrome. J Bone Joint Surg Am 75(11):1585–1592

10. Aroori S, Spence RA (2008) Carpal tunnel syndrome. Ulster Med

J 77(1):6–17

11. Sezgin M, Incel NA, Serhan S, Camdeviren H, As I, Erdogan C

(2006) Assessment of symptom severity and functional status in

patients with carpal tunnel syndrome: reliability and functionality

of the Turkish version of the Boston Questionnaire. Disabil

Rehabil 28(20):1281–1285

12. Brown AK, Quinn MA, Karim Z, Conaghan PG, Peterfy CG,

Hensor E, Wakefield RJ, O’Connor PJ, Emery P (2006) Presence

of significant synovitis in rheumatoid arthritis patients with dis-

ease-modifying antirheumatic drug-induced clinical remission:

evidence from an imaging study may explain structural pro-

gression. Arthritis Rheum 54(12):3761–3773

13. Filippucci E, Iagnocco A, Salaffi F, Cerioni A, Valesini G, Grassi

W (2006) Power Doppler sonography monitoring of synovial

perfusion at the wrist joints in patients with rheumatoid arthritis

treated with adalimumab. Ann Rheum Dis 65(11):1433–1437

14. Practice parameter for carpal tunnel syndrome (summary state-

ment) (1993) Report of the quality standards subcommittee of the

American academy of neurology. Neurology 43(11):2406–2409

15. Padua L, Pazzaglia C, Caliandro P, Granata G, Foschini M,

Briani C, Martinoli C (2008) Carpal tunnel syndrome: ultrasound,

neurophysiology, clinical and patient-oriented assessment. Clin

Neurophysiol 119(9):2064–2069

16. Carmona L, Gonzalez-Alvaro I, Balsa A, Angel Belmonte M,

Tena X, Sanmartı R (2003) Rheumatoid arthritis in Spain:

occurrence of extra-articular manifestations and estimates of

disease severity. Ann Rheum Dis 62(9):897–900

17. Agarwal V, Singh R, Wiclaf F, Chauhan S, Tahlan A, Ahuja CK,

Goel D, Pal L (2008) A clinical, electrophysiological, and path-

ological study of neuropathy in rheumatoid arthritis. Clin Rheu-

matol 27(7):841–844

18. Lanzillo B, Pappone N, Crisci C, di Girolamo C, Massini R,

Caruso G (1998) Subclinical peripheral nerve involvement in

patients with rheumatoid arthritis. Arthritis Rheum 41(7):1196–

1202

19. Ziswiler HR, Reichenbach S, Vogelin E, Bachmann LM, Villiger

PM, Juni P (2005) Diagnostic value of sonography in patients

with suspected carpal tunnel syndrome: a prospective study.

Arthritis Rheum 52(1):304–311

20. Koyuncuoglu HR et al (2005) The value of ultrasonographic

measurement in carpal tunnel syndrome in patients with negative

electrodiagnostic tests. Eur J Radiol 56(3):365–369

21. Hammer HB, Hovden IA, Haavardsholm EA, Kvien TK (2006)

Ultrasonography shows increased cross-sectional area of the

median nerve in patients with arthritis and carpal tunnel syn-

drome. Rheumatology (Oxford) 45(5):584–588

22. Khurana R, Berney SM (2005) Clinical aspects of rheumatoid

arthritis. Pathophysiology 12(3):153–165

Rheumatol Int (2012) 32:2313–2319 2319

123