Power Doppler ultrasonographic assessment of the ankle in patients with inflammatory rheumatic diseases

Table 1 The Outcome measures in rheumatology clinical trials definitions of ultrasound pathological findings

RA bone erosion	An intra-articular discontinuity of the bone surface that is visible in two perpendicular planes
Synovial fluid	Abnormal hypoechoic or anechoic (relative to subdermal fat, but sometimes may be isoechoic or hyperechoic) intra-articular material that is displaceable and compressible, but does not exhibit a Doppler signal
Synovial hypertrophy	Abnormal hypoechoic (relative to subdermal fat, but sometimes may be isoechoic or hyperechoic) intra-articular tissue that is nondisplaceable and poorly compressible and which may exhibit a Doppler signal
Tenosynovitis	Hypoechoic or anechoic thickened tissue with or with- out fluid within the tendon sheath, which is seen in two perpendicular planes and which may exhibit a Doppler signal
Enthesopathy	Abnormally hypoechoic (loss of normal fibrillar architecture) and/or thickened tendon or ligament at its bony attachment (may occasionally contain hyperechoic foci consistent with calcification), seen in two perpendicular planes that may exhibit a Doppler signal and/or bony changes, including enthesophytes, erosions, or irregularity

RA: Rheumatoid arthritis.

Table 2 Patient positions for ultrasound examination of ankle structures

Supine, with flexed knee, foot on the examination bed

Tibiotalar joint: anterior recess

Talonavicular joint

Subtalar joint: lateral and medial recess

Tendon compartments

Anterior: Tibialis anterior tendon

Extensor hallucis longus tendon

Extensor digitorum longus tendon

Lateral: Peroneus brevis tendon

Peroneus longus tendon

Medial (frog position):

Tibialis posterior tendon

Flexor digitorum longus tendon

Flexor hallucis longus tendon

Prone, with the foot hanging over the examination bed

Achilles tendon

Superficial and retrocalcaneal bursae

Subtalar joint: posterior recess

Table 3 The frequencies of various pathologies in the symptomatic ankles with either early or established rheumatoid arthritis

	Early RA	Established RA	Overall
Number of ankles	62	38	100
Joint synovitis
Talocrural joint synovitis	32.2%	39.5%	35.0%
Subtalar joint synovitis	30.7%	36.8%	33.0%
Talonavicular joint synovitis	27.4%	26.3%	27.0%
Overall	48.4%	68.4%	56.0%
Tenosynovitis
Ankle flexors (TP, FDL, FHL)	54.8%	31.6%	46.0%
Peroneal tendons (PB, PL)	33.9%	21.1%	29.0%
Ankle extensors (TA, EHL, EDL)	12.9%	5.3%	10.0%
Overall	69.4%	47.4%	61.0%
Achilles tendon involvement
Retrocalcaneal bursitis	35.5%	13.2%	27.0%
AT enthesitis	19.4%	26.3%	22.0%
AT tendonitis	12.9%	13.2%	13.0%
AT paratenonitis	8.1%	2.6%	6.0%
Overall	38.7%	39.5%	39.0%

TP: Tibialis posterior; FDL: Flexor digitorum longus; FHL: Flexor hallucis longus; PB: Peroneus brevis; PL: Peroneus longus; TA: Tibialis anterior; EDL: Extensor digitorum longus; EHL: Extensor hallucis longus; AT: Achilles tendon; RA: Rheumatoid arthritis.