Re: hand, wrist 힘줄 파열 초음파 진단

[문형철]

J Ultrason

. 2021 Dec 15;21(87):e306–e317. doi: 10.15557/JoU.2021.0052

Sonography of tendon pathology in the hand and wrist

Andrea B Rosskopf 1,2,✉, Carlo Martinoli 3,4, Luca M Sconfienza 5,6, Salvatore Gitto 6, Mihra S Taljanovic 7,8, Riccardo Picasso 4, Andrea Klauser 9

• Author information
• Article notes
• Copyright and License information

PMCID: PMC8678645  PMID: 34970442

Abstract

Traumatic and non-traumatic tendon lesions are common at the wrist and hand. For the diagnosis, therapy management, and long-term prognosis of tendon lesions, a detailed understanding of the complex anatomy and knowledge of typical injury patterns is crucial for both radiologists and clinicians. Improvements in high-resolution ultrasound are producing high-quality images of the superficial tendinous and peritendinous structures. Thus, ultrasound is a valuable first-choice tool for visualizing traumatic, inflammatory, and degenerative conditions of the extensor and flexor tendons, particularly with the advantage of possible dynamic examination. The additional use of duplex-Doppler and power Doppler ultrasound imaging is recommended for detection of tenosynovitis in overuse injury, inflammatory disease, infection, and after traumatic conditions. In traumatic tendon injuries, knowing the precise injury zone is important for treatment decision-making. In cases of tendon rupture, the radiologist should report the tear type (i.e., complete or partial-thickness) and assess the degree of tendon retraction and associated avulsion injury, including the degree of fragment displacement. The function of intact flexor tendons may be impaired by thickening, strain, or rupture of corresponding annular pulleys. This review describes in detail the typical ultrasound imaging features of common pathologies of hand and wrist tendons, including annular pulley lesions.

초록

손목과 손에서

외상성 및 비외상성 힘줄 손상은 흔히 발생합니다.

힘줄 손상의 진단, 치료 관리, 장기 예후를 위해

방사선과 의사 및 임상 의사 모두에게

복잡한 해부학적 구조에 대한 상세한 이해와 전형적인 손상 패턴에 대한 지식이 필수적입니다.

고해상도 초음파 기술의 발전은

표면 힘줄 및 힘줄 주변 구조물의 고품질 이미지를 제공しています.

따라서

초음파는 외상성, 염증성, 퇴행성 질환으로 인한

신전 및 굴곡 건의 시각화에 유용한 첫 번째 선택 도구입니다.

특히 동적 검사가 가능하다는 장점이 있습니다.

과사용 손상, 염증성 질환, 감염, 외상 후 상태에서 건막염을 진단하기 위해

듀플렉스 도플러 및 파워 도플러 초음파 영상의 추가 사용이 권장됩니다.

외상성 힘줄 손상에서 정확한 손상 부위를 파악하는 것은

치료 결정에 중요합니다.

힘줄 파열 경우, 방사선과 의사는

파열 유형(예: 완전 또는 부분 두께)을 보고하고

힘줄 수축 정도 및 연관된 박리 손상(파편 이동 정도 포함)을 평가해야 합니다.

정상적인 굴곡 건의 기능은

해당 고리형 풀리(annular pulley)의 두꺼워짐, 긴장, 또는

파열로 인해 손상될 수 있습니다.

이 리뷰는

손과 손목 건의 일반적인 병리학적 소견,

특히 고리형 풀리 손상의 초음파 영상 특징을 상세히 설명합니다.

Keywords: tendon injury, hand, pulley injury, tenosynovitis, ultrasound

Introduction

At the center of our daily life activities, the hand is frequently exposed to both direct and indirect trauma and overuse injuries(1). Therefore, the detection and detailed eval‎uation of hand injuries are common referral indications for ultrasound (US) examinations. Most injuries to the hand are open injuries. These injuries occur more commonly to the extensor tendons rather than the flexor tendons(2). This review covers the most common injury patterns of pulleys, flexor and extensor tendons in the wrist and lesser fingers for a reader with a comprehensive knowledge of normal hand and wrist anatomy (for a detailed review of normal anatomy, please read the article by De Maeseneer et al.(3) in a previous issue of this journal). Tendons at the wrist level can be examined with a linear US transducer (10–18 MHz). However, abnormalities of the extensor tendons in the fingers are better assessed using a high-frequency US probe (14–33 MHz) such as a “hockey-stick” transducer with a smaller field-of-view, and a diligent scanning procedure.

소개

일상 생활의 중심에 있는 손은

직접적 및 간접적 외상 및 과사용 손상에 자주 노출됩니다(1).

따라서

손 손상의 검출 및 상세한 평가가 초음파(US) 검사의 일반적인 의뢰 지표입니다.

손의 대부분의 손상은

개방성 손상입니다.

이러한 손상은

굴곡 건보다 신전 건에서 더 자주 발생합니다(2).

이 리뷰는 손과 손목의 정상 해부학에 대한 포괄적인 지식을 갖춘 독자를 대상으로 손목과 손가락의 작은 관절에서 가장 흔한 풀리, 굴곡 및 신전 건의 손상 패턴을 다룹니다(정상 해부학에 대한 자세한 검토는 이 저널의 이전 호에 게재된 De Maeseneer et al.(3)의 논문을 참고하시기 바랍니다). 손목 수준의 힘줄은 선형 초음파 트랜스듀서(10–18 MHz)로 검사할 수 있습니다. 그러나 손가락의 신전 힘줄 이상은 작은 시야를 가진 “하키 스틱” 트랜스듀서와 같은 고주파 초음파 프로브(14–33 MHz)와 세심한 스캔 절차를 사용하여 더 정확히 평가할 수 있습니다.

Extensor tendonsTears and ruptures

Extensor tendon tears may be the result of open injuries or closed ruptures. The classification of extensor tendon injuries into anatomical zones (by Kleinert and Verdan, Fig. 1) and the eval‎uation of injury characteristics by imaging are essential tools for the selection of the appropriate treatment(4). In every case of a tendon tear, the radiologist should report the following details for the referring surgeon(5):

신전 힘줄파열 및 단열

신전건 파열은 개방성 손상이나 폐쇄성 파열로 인해 발생할 수 있습니다. 신전건 손상을 해부학적 구역(Kleinert와 Verdan, 그림 1)으로 분류하고 영상 검사를 통해 손상 특성을 평가하는 것은 적절한 치료법을 선택하는 데 필수적인 도구입니다(4). 모든 신전건 파열 사례에서 방사선과 의사는 의뢰 외과 의사에게 다음과 같은 세부 사항을 보고해야 합니다(5):

Fig. 1.

Open in a new tab

Zonal classification of extensor tendon injuries: from distal to proximal, odd numbers conventionally refer to specific joint levels. In the fingers: zone I indicates the DIP joint level, zone III the PIP joint, zone V the MCP joint; in the thumb: the IP joint level is zone I, the MCP joint is zone III

•  
•  
•  
•  

Full-thickness tears present on US as an absolute disruption of the tendon continuity (Fig. 2)(6,7). In acute indirect injury, tendon stumps are typically thickened and appear hypoechoic with inhomogeneities and loss of the normal fibrillar echotexture. After direct injury, the stumps typically appear even. Both static and dynamic US scanning should be used to assess the gap between the tendon stumps in order to inform the surgeon`s incision planning.

신전건 손상의 구역 분류: distal에서 proximal로, 홀수 번호는 일반적으로 특정 관절 수준을 의미합니다. 손가락의 경우: 구역 I은 DIP 관절 수준, 구역 III은 PIP 관절, 구역 V은 MCP 관절을 나타냅니다; 엄지손가락의 경우: IP 관절 수준은 구역 I, MCP 관절은 구역 III

• 파열의 정확한 위치;
• 파열 유형: 완전 파열 또는 부분 두께 파열;
• 부분 두께 파열의 경우: 건의 파열된 비율;
• 완전 건 파열의 경우: 건의 수축 정도 및 동반된 박리 손상, 박리된 뼈 조각의 이동 정도를 포함합니다.

완전 두께 파열은 초음파에서 힘줄 연속성의 절대적 단절로 나타납니다 (그림 2)(6,7). 급성 간접 손상 시 힘줄 잔여물은 두꺼워지고 이질성과 정상적인 섬유질 에코 텍스처의 상실을 동반한 저음영으로 나타납니다. 직접 손상 후, 잔여부는 일반적으로 평평하게 보입니다. 힘줄 잔여부 사이의 간격을 평가하기 위해 정적 및 동적 초음파 검사를 모두 사용하여 외과의사의 절개 계획을 안내해야 합니다.

Fig. 2.

Open in a new tab

Extensor pollicis longus full-thickness tear. A. Photograph showing a sutured wound over the dorsal thumb due to a penetrating injury by a glass fragment. B. After repair, long-axis 22–8 MHz US image shows signs of extensor pollicis longus retear. Note the subtotal discontinuity of the proximal tendon end (arrowheads) which appears retracted away from the sutures (thin arrow). Mild fluid (asterisk) fills the gap

장지신근(Extensor pollicis longus) 완전 파열. A. 유리 조각에 의한 관통 손상으로 인해 엄지 손등에 봉합된 상처의 사진. B. 수리 후, 장축 22–8 MHz 초음파 영상에서 장지신근 재파열의 징후가 관찰됩니다. 근위부 힘줄 끝의 부분적 연속성 결손(화살표)이 봉합선에서 멀어져 수축된 모습을 보입니다 (얇은 화살표). 경미한 체액(별표)이 틈을 채우고 있습니다.

Partial-thickness tears typically present on US as an incomplete interruption in tendon continuity or focal disturbance of the parallel fiber lining. A hypoechoic or anechoic tendon defect is commonly observed, along with fusiform tendon swelling(6,7). Furthermore, a hematoma in the synovial tendon sheath is often seen in acute settings. In chronic lesions, hypoechoic areas with fibrosis and adhesions typically surround the ruptured tendon. Bony fragments in cases with associated fractures may present as hyperechoic areas with posterior shadowing on US imaging(5,7). An US finding of an uninterrupted, hypomobile tendon is often reported in healed finger injuries due to tendon elongation. In such cases, the examiner can use passive flexion and extension movements of the finger (and its comparison to other fingers or the contralateral side) in order to detect any mild gliding abnormalities.

부분 두께 파열은 초음파에서 힘줄 연속성의 불완전한 단절 또는 평행 섬유층의 국소적 장애로 나타납니다. 저음향 또는 무음향 힘줄 결손이 흔히 관찰되며, fusiform 힘줄 부종이 동반됩니다(6,7). 급성 경우 관절막 힘줄 피막 내 혈종이 자주 관찰됩니다. 만성 병변에서는 파열된 힘줄을 둘러싸고 섬유화 및 유착을 동반한 저음영 영역이 일반적으로 관찰됩니다. 골절이 동반된 경우 골편은 초음파 영상에서 후방 그림자를 동반한 고음영 영역으로 나타날 수 있습니다(5,7). 힘줄 연장 때문에 치유된 손가락 손상에서 힘줄의 연속성이 유지되고 운동 범위가 제한된 초음파 소견이 자주 보고됩니다. 이러한 경우 검사자는 손가락의 수동적 굴곡 및 신전 운동(다른 손가락이나 반대쪽과 비교)을 통해 경미한 미끄러짐 이상을 감지할 수 있습니다.

The term “mallet finger” or “baseball finger” refers to a deformity of the finger due to injury of the extensor tendon at its insertion point along the base of the distal phalanx(5,7,8) (zone #1 injury; Fig. 3 and Fig. 4). The terminal portion of the tendon may rupture directly, or it may be torn from the insertion point with a small piece of bone, i.e., a so-called “bony avulsion injury” (Fig. 4). The typical injury mechanism is a sudden, forceful hyperflexion of an extended DIP joint, such as when a flying ball strikes the fingertip(8). If left untreated, a mallet finger may progress to a DIP joint flexion deformity and eventually result in a swan neck deformity.

망치 손가락

“망치 손가락” 또는 “야구 손가락”이라는 용어는 원위 지골 기저부에서 신근 힘줄의 부착 부위 손상으로 인한 손가락 변형을 의미합니다(5,7,8) (존 #1 손상; 그림 3 및 그림 4). 건의 말단 부분이 직접 파열될 수 있으며, 또는 뼈 조각과 함께 부착점에서 찢어져 나올 수 있습니다. 즉, 이른바 “뼈 박리 손상”(그림 4)입니다. 전형적인 손상 메커니즘은 확장된 DIP 관절의 갑작스럽고 강한 과신전입니다. 예를 들어 날아오는 공이 손가락 끝을 강타하는 경우(8). 치료를 받지 않으면 말렛 손가락은 DIP 관절 굴곡 변형으로 진행될 수 있으며, 결국 백조 목 변형으로 이어질 수 있습니다.

Fig. 3.

Open in a new tab

Schematic drawing of the extensor mechanism of the fingers with corresponding transverse slices: (1) terminal tendon, (2) lateral conjoined tendon, (3) medial conjoined tendon, (4) lateral slip, (5) central slip, (6) medial slip (7) sagittal bands

Fig. 4.

Open in a new tab

Mallet finger. A. On a longitudinal sonogram, the extensor tendon of the fourth finger (arrows) is completely torn from the distal phalanx (Distal Ph) base. The tendon stump is thickened and hypoechoic at the level of the distal third of the middle phalanx (Middle Ph). Tendon retraction (caliper) measured 4–5 mm. B. On a longitudinal T2-weighted MRI image, the extensor tendon retraction (arrows) is shown in the same patient

Typical US findings in mallet fingers include a defect at the insertion point observed as a space during DIP flexion that closes during DIP extension, a swollen tendon over the distal middle phalanx, and a hypomobile deep flexor tendon(9).

If bone is not involved, mallet finger injuries are stabilized in a splint for several weeks. Surgery is recommended for cases with complex injury patterns, such as fractures involving more than 30–50% of the joint surface or posttraumatic malalignment of the DIP joint, in order to prevent development of a swan neck deformity or a prolonged extension deficit(8).

망치 손가락의 전형적인 초음파 소견에는 DIP 굴곡 시 관찰되는 공간으로 나타나는 부착점 결손, 원위 중수골 위의 부어오른 힘줄, 그리고 저운동성 깊은 굴곡 힘줄이 포함됩니다(9).

뼈가 관여하지 않는 경우 말렛 손가락 손상은 몇 주 동안 부목으로 고정됩니다. 관절 표면의 30–50% 이상이 골절되거나 DIP 관절의 외상 후 부정렬이 있는 복잡한 손상 패턴의 경우, 백조 목 변형이나 장기적인 확장 결손의 발생을 방지하기 위해 수술이 권장됩니다(8).

Central slip lesion

Less common sports injuries are closed disruptions of the central slip (Fig. 3) at the base of the middle phalanx. They may occur with or without bony fragment avulsion(5,10,11) (zone #3 injury, Fig. 1 and Fig. 5). In the acute phase, detection of central slip lesions may be difficult by clinical examination alone. The PIP joint may still extend due to the intact lateral slips. If a central slip lesion is overlooked, the patient often returns after 2–3 weeks with a so-called “boutonnière deformity” (Fig. 5). This term refers to a flexion deformity of the PIP joint and hyperextension of the DIP joint(12) and is caused by an increased triangular ligament tension resulting in palmar migration of the lateral slip. The boutonnière deformity often remains permanent since the tendon will heal with splinting, but in a lengthened position. Therefore, the key to a good outcome after central slip rupture is an early diagnosis and initiation of a full-time splinting(12).

중앙 슬립 손상

덜 흔한 스포츠 손상은 중수골 기저부의 중앙 슬립이 폐쇄적으로 파열되는 것입니다(그림 3). 이 손상은 뼈 조각이 파열되지 않은 상태로 발생할 수도 있습니다(5,10,11) (구역 #3 손상, 그림 1 및 그림 5). 급성기에는 임상 검사만으로는 중앙 슬립 손상을 발견하기 어려울 수 있습니다. PIP 관절은 측부 슬립이 손상되지 않아 여전히 확장될 수 있습니다. 중앙 슬립 손상이 간과되면 환자는 2~3주 후 '부토니에르 변형'이라고 불리는 증상으로 재발할 수 있습니다. (그림 5). 이 용어는 PIP 관절의 굴곡 변형과 DIP 관절의 과신전(12)을 의미하며, 삼각 인대의 긴장 증가로 인해 측부 슬립이 손바닥 쪽으로 이동하여 발생합니다. 버튼니에르 변형은 부목 고정으로 힘줄이 치유되지만, 길이가 늘어난 상태로 치유되기 때문입니다. 따라서 중앙 슬립 파열 후 좋은 결과를 얻기 위한 핵심은 조기 진단과 전일제 부목 고정(12)의 조기 시작입니다.

Fig. 5.

Open in a new tab

Boutonniere deformity. A. Lateral radiograph and B. corresponding long-axis 17–5 MHz US image of the middle finger demonstrate a small piece of bone (arrow) avulsed from the base of the middle phalanx. In B, the donor site of avulsion (thin arrow) is shown as a small concavity at the base of the middle phalanx. The retracted fragment (large arrow) is in continuity with the central slip (arrowheads) of the extensor hood

For diagnosis, the US probe should be placed over the dorsal PIP joint in longitudinal alignment with the central slip. A pre-insertional extensor mechanism defect and impaired central slip gliding in finger flexion and extension are the primary diagnostic factors. Unfortunately, the anomalous location of the displaced lateral slip is more difficult to detect with US.

부토니에르 변형. A. 측면 방사선 사진과 B. 중지 손가락의 장축 17–5 MHz 초음파 이미지는 중수골 기저부에서 분리된 작은 뼈 조각(화살표)을 보여줍니다. B에서 골절 부위(얇은 화살표)는 중수골 기저부의 작은 함몰로 나타납니다. 수축된 조각(큰 화살표)은 신전근 덮개의 중앙 슬립(화살표 머리)과 연속성을 유지하고 있습니다.

진단을 위해 초음파 프로브는 중앙 슬립과 종축으로 정렬된 상태에서 등측 PIP 관절 위에 배치해야 합니다. 지골 굴곡 및 신전 시 확장기 메커니즘 결손과 중앙 슬립의 미끄러짐 장애가 주요 진단 요인입니다. 불행히도, 이탈된 측방 슬립의 이상적인 위치는 초음파로 탐지하기 어렵습니다.

Sagittal band disruption

Sagittal bands are the most important component of the dorsal extensor hood at the metacarpophalangeal (MCP) joint (Fig. 3). The superficial and deep layers of the sagittal bands attach to the palmar plate volarly and to the extensor tendon dorsally(3). The extensor digitorum communis (EDC) tendon is stabilized at the MCP joint and protected from subluxation during digital movement by the sagittal bands. The radial band is thinner and weaker than the ulnar band. Closed disruption of an EDC tendon sagittal band (zone #5 injury; Fig. 6) is a common injury after direct trauma to the proximal phalanx or the dorsal aspect of the MCP joint. Most often the third digit(10,13) is affected.

사지대 밴드 파열

사지대 밴드는 손가락 관절(MCP 관절)의 등측 확장기 덮개에서 가장 중요한 구성 요소입니다(그림 3). 사지대 띠의 표면층과 심층은 손바닥 쪽으로 손바닥 판에, 등쪽으로는 신전 건에 부착됩니다(3). 신전 지골 공통 건(EDC)은 MCP 관절에서 안정화되며, 손가락 운동 시 탈구로부터 사지대 띠에 의해 보호됩니다. 방사형 띠는 척골형 띠보다 얇고 약합니다. EDC 건 사지대 띠의 폐쇄성 파열 (존 #5 손상; 그림 6)은 근위 지골이나 MCP 관절의 등쪽에 직접적인 외상이 가해졌을 때 흔히 발생하는 손상입니다. 가장 자주 영향을 받는 손가락은 세 번째 손가락(10,13)입니다.

Fig. 6.

Open in a new tab

Sagittal band injury. A, B. Transverse 17–5 MHz US images over the dorsal aspect of the metacarpal head (MetH) of the right third finger acquired in extension (A) and in clenched-fist (B) position show transient ulnar dislocation of the common extensor tendon (arrowheads) during flexion. Mild local effusion (asterisks) is observed along the tendon path. C. Correlative photograph showing tendon dislocation (arrow) on the ulnar side of the third metacarpal head

Injuries to the sagittal band are classified into three types(5):

•  
•  
•  

Consequently, the EDC tendon may dislocate to the radial or ulnar side, such that the finger cannot actively extend at the MCP joint(14). Radial-sided ruptures of the sagittal band in particular frequently result in tendon instability. In dynamic US, sporadic snapping of the EDC tendon to one side (subluxation) or dislocation of the tendon between the metacarpal heads can be observed when the fist is clenched(13).

Acute injuries are treated with immobilization (splint in joint extension), whereas chronic lesions require surgical reconstruction of the injured sagittal band.

사지대 손상. A, B. 오른쪽 세 번째 손가락의 손바닥면(MetH)에 대한 17–5 MHz 초음파 영상(A)과 주먹을 쥔 자세(B)에서 촬영된 영상은 굴곡 시 공통 신전 건의 일시적인 척골 탈구(화살표)를 보여줍니다. 힘줄 경로를 따라 경미한 국소 삼출(별표)이 관찰됩니다. C. 제3 중수골 두의 척골 측에 힘줄 탈구(화살표)를 보여주는 상관 사진

사지탈 밴드 손상은 세 가지 유형으로 분류됩니다(5):

• 국소 타박상(유형 1);
• 반탈구(유형 2);
• 탈구(유형-3)로 분류됩니다.

이로 인해 EDC 건이 방사측 또는 척골측으로 탈구되어 MCP 관절에서 손가락을 능동적으로 펴지 못할 수 있습니다(14). 특히 방사측 사지대 파열은 건 불안정성을 자주 유발합니다. 동적 초음파 검사에서 주먹을 쥐었을 때 EDC 건이 한쪽으로 간헐적으로 튀어오르는 현상(부분 탈구) 또는 건이 중수골 머리 사이로 탈구되는 현상이 관찰될 수 있습니다(13).

급성 손상은 고정(관절 확장 상태의 부목)으로 치료되며, 만성 병변은 손상된 사지대 밴드의 수술적 재건이 필요합니다.

Extensor tenosynovitis

The term “tenosynovitis” is defined as any inflammation and swelling of the synovial sheath. Inflammatory processes, trauma, and overuse injuries lead to damage of the extrinsic extensor tendons and the surrounding tendon sheaths(15). In chronic tenosynovitis, one will find tears and ruptures of the tendons, as well as neighboring bony changes such as erosions or periosteal reactions.

Tenosynovitis may affect each extensor compartment (Fig. 7) at the level of the wrist(16).

신장건 활액막염

“건막염”은 활막막의 염증과 부종을 의미합니다. 염증 과정, 외상, 과사용 손상은 외재성 신근 건과 주변 건막막에 손상을 입힙니다(15). 만성 건막염에서는 건의 파열 및 파열, 주변 뼈의 변화(예: 침식 또는 골막 반응)가 관찰됩니다.

건막염은 손목 수준에서 각 신근 구획(그림 7)에 영향을 미칠 수 있습니다(16).

Fig. 7.

Schematic drawing of the six extensor tendon compartments of the wrist, labeled from I-VI, adapted from(34). APL – abductor pollicis longus; EPB – extensor pollicis brevis; ECRL – extensor carpi radialis longus; ECRB – extensor carpi radialis brevis; EPL – extensor pollicis longus; EIP – extensor indicis proprius; EDC – extensor digitorum communis; EDM – extensor digiti minimi; ECU – extensor carpi ulnaris; Asterisk – subsheath; LT – Lister’s tubercle; Note the retinacula for each compartment are removed for better visibility

그림 7.

손목의 6개 신근 힘줄 구획을 I-VI로 표시한 도식도,(34)에서 수정. APL – 엄지 외전근 장근; EPB – 엄지 신근 단근; ECRL – 요골 측 손목 신근 장근; ECRB – 요골 측 손목 신근 단근; EPL – 엄지 신근 장근; EIP – 검지 신근 근육; EDC – 손가락 신근 근육; EDM – 소지 신근 근육; ECU – 척골 손목 신근 근육; 별표 – 하부 피막; LT – 리스터 결절; 각 구획의 유지막은 가시성을 위해 제거되었습니다

First and second compartments

Tenosynovitis occurs most commonly in the first compartment as “De Quervain`s syndrome” (Fig. 8). This chronic injury stems from the overuse and repetitive movement of the extensor pollicis brevis (EPB) and the abductor pollicis longus (APL) tendons under the retinaculum at the level of the distal radius(17). Initially, this manifests as tendon edema, ensuing constriction of the tendon against the retinaculum, and thickening of the retinaculum, caused by microinjuries and impaired healing.

첫 번째 및 두 번째 구획

건막염은 주로 첫 번째 구획에서

“De Quervain`s syndrome” (Fig. 8)로 발생합니다.

이 만성 손상은 손목의 원위부 수준에서 건막 아래에서 extensor pollicis brevis (EPB)와 abductor pollicis longus (APL) 건의 과사용과 반복적인 움직임에서 기인합니다(17). 초기에는 건 부종으로 시작되어 건이 망막막에 압박되어 협착되고, 미세 손상과 치유 장애로 인해 망막막이 두꺼워집니다.

Fig. 8.

Open in a new tab

De Quervain’s syndrome. Short- (A) and long-axis (B) 24–8 MHz US images over the radial styloid reveal a thickened, hypoechoic retinaculum (arrowheads) and the swollen abductor longus and extensor pollicis brevis tendons. Note that the two tendons form a rounded complex and cannot be separated from each other, being constricted by the abnormal retinaculum

Dynamic US scanning, preferably in the long-axis view, may detect real-time gliding of the obstructed tendon under the retinaculum(17). The normal oval shape of the EPB and APL tendons on short-axis view typically changes to a rounder appearance in chronic settings. Thickened tendons also lead to partial tears of the retinaculum. In the acute stage, increased vascularization is observed in both the tendons and the retinaculum, whereas in chronic conditions, thickening and fibrotic lesions are observed. Sometimes a vertical septum is observed as having divided the first compartment into two discrete tunnels and increasing the risk of tenosynovitis. In such cases, only the EPB is typically involved, while the APL tendon remains unaffected (Fig. 9). Common causes of De Quervain’s syndrome include sporting activities that require repetitive flexion or extension of the wrist in combination with thumb abduction against resistance. This syndrome develops frequently during new motherhood (“baby wrist”) due to hormonal changes and an incorrect wrist position while lifting the baby(18).

데 쿠르바인 증후군.

단축축(A) 및 장축축(B) 24–8 MHz 초음파 영상에서 방사골 돌기 부위의 두꺼워지고 저음영을 보이는 망막막(화살표)과 부어오른 장지근과 짧은 엄지신근 힘줄이 관찰됩니다. 두 힘줄은 둥근 복합체를 형성하여 서로 분리되지 않으며, 이상적인 망막막에 의해 압박받고 있습니다.

동적 초음파 검사는

장축 방향에서 수행할 경우,

망막막 아래에서 차단된 건의 실시간 미끄러짐을 감지할 수 있습니다.(17)

단축축 방향에서

정상적인 타원형 모양의 EPB 및 APL 건은 만성 단계에서 더 둥근 모양으로 변합니다.

두꺼워진 건은 망막막의 부분 파열을 유발합니다.

급성기에는

힘줄과 망막 모두에서 혈관 신생이 증가하지만,

만성 상태에서는 두꺼워짐과 섬유화 병변이 관찰됩니다.

때로는 수직 격막이 첫 번째 구역을 두 개의 분리된 터널로 나누어 건막염 위험을 증가시키는 경우가 있습니다. 이러한 경우 일반적으로 EPB만 영향을 받고 APL 힘줄은 영향을 받지 않습니다(그림 9). 드 케르반 증후군의 일반적인 원인은 저항을 받으며 손목을 반복적으로 구부리거나 펴는 운동입니다. 이 증후군은 호르몬 변화와 아기를 들 때 손목의 잘못된 자세로 인해 새로운 엄마에게 자주 발생합니다(18).

Fig. 9.

Open in a new tab

De Quervain’s syndrome in a 20-year-old patient, related to selective entrapment of the extensor pollicis brevis by a thickened retinaculum. A. Transverse US image shows a vertical septum (thin white arrow) dividing the two tendons in the first compartment. Fluid (thick white arrow) is seen surrounding the extensor pollicis brevis tendon (EPB; yellow asterisk) due to tenosynovitis. Note the thickening of the surrounding retinaculum (yellow arrow heads). The abductor pollicis longus (white asterisk) and the ventral part of the retinaculum (white arrowhead) are unaffected. The transverse color Doppler image (B) and transverse power Doppler image (C) show increased vascularization (arrow heads) surrounding the EPB tendon due to tenosynovitis

그림 9.

새 탭에서 열기

20세 환자의 De Quervain 증후군으로, 두꺼워진 retinaculum에 의한 extensor pollicis brevis의 선택적 압박과 관련이 있습니다. A. 가로 초음파 영상에서 첫 번째 구획의 두 힘줄을 나누는 수직 격막(얇은 흰색 화살표)이 보입니다. 건막염으로 인해 엄지손가락 신근근(EPB; 노란 별표)을 둘러싼 체액(두꺼운 흰색 화살표)이 관찰됩니다. 주변 건막의 두꺼워짐 (노란색 화살표 머리)를 둘러싸고 있습니다. 엄지 외전근(abductor pollicis longus; 흰색 별표)과 인대막의 복부(흰색 화살표 머리)는 영향을 받지 않았습니다. 가로 색상 도플러 영상(B)과 가로 파워 도플러 영상(C)에서 건막염으로 인해 EPB 건 주위에 혈관 증가(화살표 머리)가 관찰됩니다.

Proximal intersection syndrome (also called crossover syndrome, peritendinitis crepitans or oarsmen’s wrist) is a type of overuse injury presenting clinically with pain and swelling at the distal forearm, some centimeter proximal to Lister’s tubercle. Here lies the intersection point of the first (APL and EPB) and the second extensor compartment (extensor carpi radialis longus (ECRL) and extensor carpi radialis brevis (ECRB) tendons)(19). US may detect edematous changes in the APL and EPB (typically at the myotendinous junctions) and the loss of a hyperechoic plane deviding the two different compartments(5,20). Other findings include sheath effusion and swelling, typically of the tendons in the second extensor compartment. Sometimes even ganglion cysts may be seen.

근위 교차 증후군 Proximal intersection syndrome (교차 증후군, peritendinitis crepitans 또는 노젓는 사람의 손목으로도 불림)은 임상적으로 전완부 말단부, Lister의 결절에서 몇 센티미터 proximal 부위에서 통증과 부종을 보이는 과사용 손상의 한 유형입니다. 이 부위는 첫 번째(APL과 EPB)와 두 번째 확장근 부위(extensor carpi radialis longus (ECRL)와 extensor carpi radialis brevis (ECRB) 힘줄)의 교차점입니다.(19) 초음파 검사는 APL과 EPB 힘줄(일반적으로 근건 접합부에서)의 부종 변화와 두 다른 구획을 구분하는 고반향 평면의 소실을 감지할 수 있습니다.(5,20) 기타 소견에는 힘줄(일반적으로 제2 신전 구획의 힘줄)의 피막 삼출액과 부종이 포함됩니다. 때로는 건낭 낭종이 관찰될 수도 있습니다.

Second and third compartments

Distal intersection syndrome occurs at the level of Lister’s tubercle, where the extensor pollicis longus (EPL) tendon, (i.e., third extensor compartment) crosses over the second extensor compartment tendons(16). The syndrome is often caused by mechanical rubbing between the tendons due to repeated flexion and extension movements of the wrist. Sheath effusion is typically observed around the EPL tendon proximal and distal to the intersection(21) (Fig. 10). During US examination, the carpal bones and joints should also be checked carefully along the full length of the tendon course, for impingement of tendons by underlying spurs or osteophytes. This syndrome can also be seen secondary to scaphoid fractures, or in patients with a scaphoid lunate advanced collapse (SLAC) wrist.

Fig. 10.

Open in a new tab

Distal intersection syndrome. A. Proximal to the criss-crossing point, transverse 17–5 MHz US image shows a distended sheath (asterisk) of the extensor pollicis longus (EPL) as it runs alongside the ulnar aspect of the extensor carpi radialis brevis (ERCB) and extensor carpi radialis longus (ECRL). B. More distally, transverse 17–5 MHz color Doppler US image demonstrates the extensor pollicis longus (EPL) as it crosses over the extensor carpi radialis brevis (ECRB) and longus (ECRL) tendons. The sheath of the second and third compartments appears mildly distended by tenosynovitis with effusion (asterisk). Note diffuse local hyperemia and the swollen appearance of the ECRB

Non-displaced Colles fractures may cause EPL tendon rupture, whereas the stabilizing screw tips in a stabilized Colles fracture may protrude dorsally, with possible impingement of the EPL tendon(22).

Fourth compartment

Patients with inflammatory or infectious disorders often present with EDC tenosynovitis (Fig. 11)(16,23). US with Doppler imaging helps to assess the activity level of inflammatory diseases and to monitor treatment effects. Tendon impingement with signs of tenosynovitis may be seen in the postoperative setting, such as following treatment of distal radius fractures with screw tip impingement (Fig. 12). Furthermore, an anomalous extensor indicis proprius muscle passing with the EDC tendon in the fourth compartment may also cause tenosynovitis, known as “extensor indicis proprius syndrome”(24).

Fig. 11.

Open in a new tab

Tenosynovitis of the fourth extensor compartment in a patient with psoriatic arthritis. A. Longitudinal US image with fluid, thickened synovium, and thickened retinaculum (white arrows) around the tendons in the fourth extensor compartment and increased vascularity on longitudinal (B) and transverse color Doppler (C) images, both in the synovium and the tendons

Fig. 12.

Open in a new tab

Screw tip impingement and tear of the extensor indicis proprius tendon in a 45-year-old woman after volar plating for distal radial fracture. A. Transverse 17–5 MHz US image obtained at the level of Lister’s tubercle (LT) reveals the thread and tip of a screw (thin arrow) impinging the extensor indicis proprius tendon. Note the intact extensor pollicis longus (EPL) and the displaced slips of the extensor digitorum communis (EDC). B. Transverse 17–5 MHz US image obtained proximal to A demonstrates the retracted extensor indicis proprius (arrowheads) surrounded by effusion and debris (asterisk). C. Longitudinal 17–5 MHz US image demonstrates the screw (thin arrow) and the empty sheath (asterisks) of the extensor indicis proprius filled with debris and hypoechoic effusion. Note the normal-appearing tendons of the extensor digitorum communis (EDC) as they run more superficially

Fifth compartment

The extensor digiti minimi (EDM) tendon is known for frequent anatomic variations with a bifurcated tendon (proximal, distal, or at level of the retinaculum), often with a concomitant synovial septum. Some studies suggested that a distally bifurcated tendon might impinge on the synovial septum during full finger flexion, inducing tenosynovitis(25). The EDM lies close to the distal radioulnar joint (DRUJ). Therefore, EDM tenosynovitis frequently occurs in patients with arthritis of the distal radioulnar joint (DRUJ). In severe tenosynovitis, synovial pannus may infiltrate the DRUJ capsule, leading to rupture of the adjacent retinaculum, ulnar head dorsal subluxation, and tendinopathy(26). Dynamic US in varying degrees of pronation and supination might be helpful in order to assess the tendon position in relation to the distal radioulnar joint.

Sixth compartment

A retinaculum-like structure known as the “subsheath” holds the extensor carpi ulnaris (ECU) tendon within a groove in the ulnar head(5,16). Chronic repetitive stress may lead to stenosing tenosynovitis of the subsheath. Typical ultrasound findings include fibrosis, reactive tenosynovial effusion, and thickening of the extensor retinaculum. A weak or torn subsheath may cause ECU tendon instability or dislocation out of the ulnar groove (Fig. 13).

Fig. 13.

Open in a new tab

DExtensor carpi ulnaris (ECU) instability. ECU instability in a patient with long-standing rheumatoid arthritis. US image demonstrates the ECU tendon (white asterisk) dislocated out of the groove (white arrows). The subsheath (void arrowheads) appears lax, wavy, and displaced out of the groove

Typical causes of subsheath tears include recurrent stress injuries (e.g., in racket sports), an abrupt twisting(27), and severe DRUJ arthritis. Note: In healthy subjects the ECU tendon “dislocates” partially with supination of the forearm (up to 50% of the groove’s width) and relocates with pronation. This can be nicely seen with dynamic ultrasound.

Flexor tendons and pulleys

High resolution US provides reliable eval‎uation of the flexor tendons of the finger (for anatomy, see Fig. 14 and Fig. 15) and distinction of tenosynovitis, partial-thickness tendon tears, and complete tears(28).

Fig. 14.

Open in a new tab

Drawing of the flexor tendons of the finger, superimposed on US image. Superficial – flexor digitorum superficialis tendon (yellow), Deep – flexor digitorum profundus tendon (green), DIP – distal interphalangeal joint, PIP – proximal interphalangeal joint, MCP – metacarpophalangeal joint, VP – volar plate

Fig. 15.

Open in a new tab

Schematic drawing of superficial (red) and deep (orange) finger flexor tendons with corresponding transverse slices. Palmar plate (blue), bone (grey)

Traumatic flexor tendon injuries

Using the anatomical classification system developed by Kleinert and Verdan(4), flexor tendon injuries are classified into 5 zones (Fig. 16). Flexor tendon injuries of the third, fourth and fifth digits are frequently open, caused by laceration, and often involve the mid-substance, but not the tendon insertion point(11). These injuries involve the flexor digitorum superficialis (FDS) tendon, the flexor digitorum profundus (FDP) tendon, or both. Injuries in Zones II to V injuries that involve the neurovascular bundle require urgent surgical repair (i.e., within 24 hours), particularly in Zone II(11)C. US permits measurement of cross-sectional flexor tendon thickness (i.e., when a tendon strain is suspected) and easy comparison with the contralateral finger(29).

Fig. 16.

Open in a new tab

Zonal classification of flexor tendon injuries: Zone I distal to the flexor digitorum superficialis (FDS) insertions, Zone II between the FDS insertions and the level of A1 pulleys, Zone III between the proximal aspect of A1 pulleys and the lumbricals origin from the flexor digitorum profundus (FDP) tendons, Zone IV at the carpal tunnel region, Zone V from the distal myotendinous junction to the carpal tunnel, TI distal thumb to the IP joint, TII between thumb IP joint and A1 pulley, and TIII at the thenar eminence

Jersey finger

The term “jersey finger” refers to a closed avulsion injury of the distal FDP tendon(27) (Fig. 17) that occurs when a DIP joint in active flexion is forcefully hyperextended. For example, in rugby or football games, a player snatches another player’s jersey with the fingertips as that player moves away(11). The fourth digit is frequently affected. FDP tendon avulsion injuries are assessed based on the extended Leddy and Packer classification(30) and largely require operative treatment. Type I injuries (i.e., FDP tendon retraction to the palm) often have compromised vascular flow and require urgent operative treatment within 7 to 10 days. Treatment options for chronic avulsion injuries older than 6 weeks depend on the function level of the digit(30).

Fig. 17.

Open in a new tab

Jersey finger. Long-axis 12–5 MHz US image of the middle finger reveals fracture of the volar aspect of the base of the distal phalanx with fragmentation (thin arrow) and proximal migration of a small piece of bone (void arrow) up to the distal edge of the A3-pulley. Note the flexor digitorum profundus tendon (white arrowheads) attached to the avulsed fragment and the empty sheath (void arrowheads) distal to it. DPh – distal phalanx; MPh – middle phalanx; PPh – proximal phalanx

Tenosynovitis of flexor tendons

Common causes of flexor tenosynovitis include overuse, local trauma, inflammatory arthritis, and infection(31).

Acute flexor tenosynovitis is characterized on US by hypoechoic or anechoic effusion in the synovial sheath, increased vascularization and distention of the tenosynovium. Furthermore, the echotexture in the involved tendon lacks the typical fibrillar pattern and the tendon appears thickened. Peritendinous edema is evident in some cases(28). Increased vascularization due to neo-vessels can be visualized with US color or power doppler in the tendon and the surrounding soft tissues(28).

In subacute and chronic cases of flexor tenosynovitis, the synovial sheath is thickened on US, and the flexor tendon is blurred(16). In infectious tenosynovitis and wound injuries, foreign bodies may be observed. In comparison, rice bodies may be found within the synovial sheath effusion in inflammatory arthritis, visualized as numerous, well-defined, floating echoic masses. US may be used for guided treatment with steroid injections, or for assessment of therapeutic treatments, with a successful response demonstrating decreased inflammatory activity.

In the fingers, the flexor tendons run through osseo-fibrous tunnels formed by the annular and cruciform pulleys and covered by the flexor retinaculum. In a “trigger-finger”, mechanical overuse causes thickening of the annular pulley, narrowing of the osseofibrous tunnel, and stenosing tenosynovitis of the adjacent flexor tendons(28)(Fig. 18).

Fig. 18.

Open in a new tab

Trigger finger. A. On an axial sonogram at the level of the fourth metacarpal head (Met IV), the A1-pulley (straight arrows) is thickened (1.5 mm). Its collateral ligaments appear artifactually hypoechoic due to anisotropy. Note the healthy A1-pulley (curved arrow) at the level of the third metacarpal head (Met III). B. On a longitudinal sonogram, A1-pulley thickening is shown. The flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP) tendons show fibrillar echotexture and synovial sheath effusion (asterisks) is seen proximally. Hash marks indicate articular cartilage; Met – metacarpal; Prox Ph – proximal phalanx; VP – volar plate

Pulley injuries

Most injuries of the annular pulleys (for anatomy, see Fig. 19A) happen in rock climbers. The A2 pulley of the third and fourth digits is most commonly affected(27). Typically, excessive stress with flexor tendon contraction against the pulley system causes pulley injury. A common risk factor for pulley injuries is the “crimp position”, with 90° or more flexion of the PIP joint and slight DIP joint hyperextension. Using high-resolution US probes, a normal annular pulley is identified as a very thin (0.3–0.5 mm) band surrounding the flexor tendons on their volar side (Fig. 19B)(5). Pulley ligaments are best visualized on transverse scanning planes: the normal US appearance of an annular pulley is hyperechoic on the volar side and hypoechoic on the lateral side (the latter due to anisotropy). The thickness of the annular pulleys is often increased (1.5-fold) in asymptomatic climbers, when compared to non-climbers(32) (Fig. 20). This structural adaptation simplifies US visualization of the pulley bands. Annular pulley injuries include pulley strains and partial or complete ruptures, involve one or multiple pulleys, and often result in variable bowstringing of the flexor tendons. Clinically, bowstringing is typically only visible when multiple injuries have occured in the A2, A3, and A4 pulleys(33). With imaging (US and MRI) the detection of minor degrees of bowstringing is more sensitive(34). The tendon–to-bone distance (TBD) increases in cases with bowstringing. US with forced flexion is used to determine the site of maximal volar bowstringing (MVB) and to diagnose which pulley has ruptured. In an A2 pulley rupture, MVB occurs over the proximal phalanx. In an A3 pulley rupture, MVB occurs at the distal proximal phalanx at level of the volar plate. In an A4 pulley rupture, MVB occurs over the middle part of the middle phalanx. US should be performed along the finger’s long axis to detect tendon bowstringing and measure TBD (Fig. 21). The transverse scanning plane is best for assessment of the site of pulley detachment and visualization of any small osseous avulsion fragments.

Fig. 20.

Open in a new tab

Transverse (A) and sagittal (C) US with normal thin appearance of A2-pulley (white arrowheads) with normal tendon-to-bone distance (TBD) in a non-climber. Transverse (B) and sagittal (D) US shows thickened A2 ligament (white arrowheads) due to chronic overuse in a climber. Images courtesy of Prof. A. Schweizer, Handsurgery, Balgrist University Hospital

Fig. 21.

Open in a new tab

Annular pulley injury. A. Longitudinal 17–5 MHz US image obtained over the injured right long finger of a 15-year-old boy during resisted flexion of the distal interphalangeal joint demonstrates bowstringing and volar displacement of the flexor tendons (arrows) secondary to acute rupture of the A2-pulley. In this particular case, there was also a combined injury of the A3- and A4-pulleys (not shown). An increased tendon-to-bone distance (>2 mm, double arrow), is seen over the proximal phalanx. Note an abundant effusion (asterisks) distending the tenosynovial sheath. B. Corresponding photograph shows volar soft-tissue swelling over the proximal (thin arrow) and middle (arrowhead) phalanges due to bowstringing of the flexor tendons. C. Longitudinal 17–5 MHz US image over the left long finger illustrates the normal A2-pulley as a thin hypoechoic band (white arrowheads) retaining the flexor tendons (arrow) against the shaft of the proximal phalanx

Dynamic US is used to eval‎uate any instability of the flexor system associated with pulley injuries. Volar tendon displacement relative to the bone is measured at rest and in forced flexion. The normal TBD at the level of the A2 pulley ligament is <2 mm(31) (Fig. 19). In a complete, isolated A2 pulley tear, the TBD at the level of the proximal phalanx is >2 mm at rest and >4 mm during forced flexion(31). In combined A2, A3, and A4 pulley tears, the TBD is >2 mm at rest and >5.5 mm during forced flexion (Fig. 21). US during forced flexion is particularly helpful for differentiation of isolated A2 pulley tears and combined A2 and A3 pulley tears(5,34). Diagnosis of partial pulley ruptures is more challenging because they produce little to no tendon displacement. In such cases, the affected pulley is hypoechoic and swollen. Abnormal vascularization can be detected in both the tendons and pulleys in acute conditions using Doppler examination. A classification system adapted from Schöffl and Schöffl (grade I-IV) for grade I to IV flexor pulley injuries is used to guide treatment decision making(35). While grade I to III injuries (i.e., strain, partial rupture, and complete rupture of a single pulley) can be managed conservatively without operation, Grade IV injuries (i.e., multiple pulley ruptures or a single rupture of A2 or A3 with concomitant trauma (ligaments/lumbrical muscles)) require surgery.