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Letter to the Editor


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Med Ultrason 2020, Vol. 22, no. 1, 114-119

Letter to the Editor

Is transthoracic lung biopsy a safe procedure?

Cezar Iulian Bețianu


, Mihaela Goicea


, Giorgiana Ion


, Andrei Bondari


1Department of Radiology and Medical Imaging, „Carol Davila” Central Military Emergency University Hospital, Bucharest, 2Radiology and Imaging Department, Faculty of Medicine, University of Medicine and Pharmacy, Craiova, Romania

Received 17.12.2019 Accepted 09.01.2020 Med Ultrason

2020, Vol. 22, No 1, 114-115, DOI: 10.11152/mu-2360, Corresponding author: Giorgiana Ion

„Carol Davila” Central Military Emergency University Hospital, Bucharest, Romania 134 Calea Plevnei, Bucharest 010825, Romania E-mail: [email protected]

To the Editor,

The transthoracic lung biopsy is a minimally invasive diagnostic procedure used for determining the manage- ment of patients with a high suspicion for malignancy lesions. Although the importance of percutaneous lung biopsy has been clearly stated by many studies [1-3], we observed that percutaneous biopsy is still regarded with great concern by both patients and physicians mostly be- cause of its possible complications. In literature, compli- cation rates after percutaneous lung biopsies reach up to 38.8 % while major complications occur in up to 5.7% of cases [3]. The most frequently described post-procedural complication is pneumothorax, occurring in 25% of cas- es [3]. Severe complications include pneumothorax re- quiring intervention, haemothorax, air embolism, needle track seeding and death [4]. Literature describes a 0.061

% rate for air embolism and tumor seeding, 0.092% rate for haemothorax and 0.07-0.15% rate for death [4]. The purpose of this letter is to point out that percutaneous lung biopsy is underappreciated since it is a rapid, ac- curate and safe diagnostic tool with a relatively low rate of complications.

A group of 317 patients underwent percutaneous lung core biopsies in our hospital between July 2015 and June 2018. The procedures were guided either by computed tomography (CT) or ultrasound (US) and were performed with 18 G Tru-cut needles. The decision for performing the biopsy as well as the selection of the puncture site

were made based on CT examinations; this was consid- ered sufficient also for subsequently US-guided proce- dures, since the morphologic correlation between CT and US in lung lesions is reliable [5]. Of the 317 patients, complications occurred in 33 cases (10.41%): 25 pneu- mothoraces (7.89%), 3 haemothoraces (0.95%), 7 alveo- lar haemorrhages (2.21%) and 1 infection at puncture site (0.32%), in a patient with decompensated diabetes mel- lites. There were no cases of air embolism, needle track seeding or death.

To sum up, the lung biopsy is a relatively safe proce- dure, given the adequate selection of patients. The com- plication rates in our hospital are comparable to larger internationally published data.


1. Galluzzo A, Genova C, Dioguardi S, Midiri M, Cajozzo M. Current role of computed tomography-guided transtho- racic needle biopsy of metastatic lung lesions. Future Oncol 2015;11(2 suppl):43-44.

2. Russo U, Sabatino V, Nizzoli R, et al. Transthoracic com- puted tomography-guided lung biopsy in the new era of personalized medicine. Future Oncol 2019;15:1125-1134.

Fig 1. A. Axial CT image shows a pulmonary tumour of 70/80 mm diameter located in the superior right lobe with chest wall and rib invasion. B. Ultrasound-guided transthoracic biopsy of the tumour. No postprocedural complications occurred.



Med Ultrason 2020; 22(1): 114-119 3. Heerink WJ, de Bock GH, de Jonge GJ, Groen HJ,

Vliegenthart R, Oudkerk M. Complication rates of CT- guided transthoracic lung biopsy: meta-analysis. Eur Ra- diol 2017;27:138-148.

4. Tomiyama N, Yasuhara Y, Nakajima Y, et al. CT-guided needle biopsy of lung lesions: A survey of severe com-

plication based on 9783 biopsies in Japan. Eur J Radiol 2006;59:60-64.

5. Chira R, Chira A, Mircea PA. Intrathoracic tumors in contact with the chest wall – ultrasonographic and com- puted tomography comparative evaluation. Med Ultrason 2012;14:115-119.

Received 02.01.2020 Accepted 05.01.2020 Med Ultrason

2020, Vol. 22, No 1, 115-116, DOI: 10.11152/mu-2395, Corresponding author: Dr. Boudier-Revéret MD

Hôtel-Dieu du Centre Hospitalier de l’Université de Montréal, 3840, Saint-Urbain St., Montreal,

QC, H2W 1T8, Canada Phone: 1-514-890-8000

E-mail: [email protected]

Suprastyloid crest of the radius in wrist ultrasonography:

a bony prominence not to mistake for Lister’s tubercle

Mathieu Boudier-Revéret


, Stéphanie Jean


, Chueh Hung Wu


1Department of Physical Medicine and Rehabilitation, Centre Hospitalier de l’Université de Montréal, Montreal, Canada, 2Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei, Taiwan

To the Editor,

Ultrasound (US) is becoming increasingly popular amongst physiatrists to diagnose and treat musculoskel- etal (MSK) pathologies. Well-designed standardized protocols have been published to scan the most common painful joints and surrounding structures. At the wrist, Lister’s tubercle, which is also known as the dorsal tu- bercle, serves as the main landmark to identify the dor- sal extensor compartments at the distal radius [1]. It is a clear boundary between the 2nd compartment, which sits on the radial side of the tubercle, and the 3rd and 4th compartments, which sit on its ulnar side. However, in many patients, another similarly shaped bony promi- nence is present between the 1st and 2nd compartments.

It is not mentioned in most reference MSK US textbooks [2,3] and is called the suprastyloid crest of the radius (fig 1, supplementary video 1, on the journal site). Its Latin name is crista suprastyloidea radii [4] and it lies just proximal to the radial styloid and corresponds to the ac-

tual insertion site of the brachioradialis muscle. In some patients with a more prominent suprastyloid crest, it might be mistaken for Lister’s tubercle by nov- ice sonographers. In that case, the 1st compartment would be misidentified as the 2nd compartment, and confusion might ensue. However, no 3rd compartment would be seen ulnar to the bony prominence, and the 2nd compart- ment does not contain as many tendons as the 4th.

Easy ways to avoid this pitfall are to palpate the bony landmarks before placing the US probe on the patient’s Fig 1. This schematic diagram depicts the anatomy of the six extensor compartments at the dorsal wrist. Lister’s tuber- cle, also known as the dorsal tubercle, (arrow) divides the 2nd and 3rd compartments, whereas the suprastyloid crest (arrow- head) divides the 1st and 2nd compartments. 1st compartment:

APL, abductor pollicis longus. EPB, extensor pollicis brevis.

2nd compartment: ECRL, extensor carpi radialis longus. ECRB, Extensor carpi radialis brevis. 3rd compartment: EPL, exten- sor pollicis longus. 4th compartment: ED, extensor digitorum.

EIP, extensor indicis proprius. 5th compartment: EDM, extensor digiti minimi. 6th compartment: ECU, extensor carpi ulnaris.


wrist. Lister’s tubercle is located more dorsally on the radius, and the suprastyloid crest is more on the radial edge of the radius, even if the distance separating the two bony prominences is often around 1.5-2 cm. Also, the ultrasonographer must use compartment anatomy to validate what compartment(s) he/she is looking at: How many tendons does it contain? What are the adjacent compartments? And of course: Where are the important bony landmarks?

Hopefully, this brief visual vignette will have educat- ed readers on one of the less known bony prominences of the dorsal wrist, the suprastyloid crest, and will allow

US professors and students to better teach and learn so- nographic anatomy.


1. Özçakar L, Kara M, Chang KV, et al. EURO-MUSCULUS/

USPRM Basic Scanning Protocols for wrist and hand. Eur J Phys Rehabil Med 2015;51:479-484.

2. Bianchi S, Martinoli C. Ultrasound of the musculoskeletal system. 2007: Springer Science & Business Media.

3. Jacobson JA. Fundamentals of Musculoskeletal Ultrasound E-Book. 3rd Edition. Elsevier Health Sciences. 2017.

4. Platzer W. Zur Anatomie der “Sellabriicke” und ihre Bezie- hung. 1992.

Ultrasound imaging for lateral gastrocnemius muscle injury:

tennis leg revisited

Yahya Doğan


, Levent Özçakar


1Hacettepe University Medical School, Department of Physical and Rehabilitation Medicine, Ankara, Turkey

To the Editor,

A 37-year-old male presented with left calf pain for the last 5-6 months. He declared that the problem had suddenly occurred during a match (playing football) and that he had become a little better after rest. In the meantime, he had received a 3-week physical therapy after which he had partially improved. Medical history and physical examination was suggestive for ‘tennis leg’

(strain at the myotendinous junction of the medial head of the gastrocnemius muscle). Accordingly, ultrasound (US) examination was also performed. While US imag- ing was negative for ‘tennis leg’, diligent sonopalpation uncovered that the patient’s complaints were actually lo- calized more on the lateral side where the myotendinous junction appeared to be asymmetric as compared to the

Received 04.12.2019 Accepted 19.12.2019 Med Ultrason

2020, Vol. 22, No 1, 116-117, DOI: 10.11152/mu-2338, Corresponding author: Yahya Doğan

Hacettepe University Medical School Department of Physical and Rehabilitation Medicine, Sıhhiye, Ankara, Turkey E-mail: [email protected] Fax number: +90 (312) 310 57 69

Fig 1. Comparative long- (A) and short-axis (B) US imaging for the calf muscles. White arrowhead shows the indentation at the myotendinous junction of the lateral head of the gastrocne- mius muscle (left images) when compared to the normal side (right images). GM; Medial head of the gastrocnemius muscle, GL; Lateral head of the gastrocnemius muscle, sc; subcutane- ous tissue.



Med Ultrason 2020; 22(1): 114-119 normal side (fig 1). In light of the US findings, the patient

was diagnosed with a healing strain of the lateral head of the gastrocnemius muscle.

Calf pain is a common complaint among patients of all ages but is most frequent in young and active peo- ple (especially runners). Often , calf strains or ruptures are seen in the medial gastrocnemius muscle (i.e. ‘tennis leg’) but other components of the posterior leg including the lateral gastrocnemius, soleus and plantaris may also harbor the underlying cause/lesion [1]. These injuries usually occur during physical activities whereby forced dorsiflexion of the ankle and simultaneous extension of the knee are inevitable. Patients commonly report a sud- den tear or ‘pop’ in their posterior leg after which they start suffering acute pain and tenderness [2]. According to the imaging studies, involvement of the medial gas- trocnemius occurs in 58 to 65% of all cases; the lateral gastrocnemius in 8 to 38% and other muscles are less frequent [2,3].

Presenting this (rare) case of ours, firstly, we em- phasise that medical history and physical examination

might sometimes be insufficient for an exact diagnosis.

Secondly, sono-palpation is definitely helpful for demon- strating and the prompt understanding of the lesion (for the physician and for the patient alike) [4]. Last but not least, especially when an intervention is to be planned, the aforementioned ‘sonographic understanding’ will turn into ‘precise targeting’ also [5].


1. Bryan Dixon J. Gastrocnemius vs. soleus strain: how to differentiate and deal with calf muscle injuries. Curr Rev Musculoskelet Med 2009;2:74-77.

2. Fields KB, Rigby MD. Muscular calf injuries in runners.

Curr Sports Med Rep 2016;15:320-324.

3. Koulouris G, Ting AYI, Jhamb A, Connell D, Kavanagh EC. Magnetic resonance imaging findings of injuries to the calf muscle complex. Skeletal Radiol 2007;36:921-927.

4. Çağlayan G, Özçakar L, Kaymak SU, Kaymak B, Tan AA.

Effects of sono-feedback during aspiration of Baker’s cysts:

A controlled clinical trial. J Rehabil Med 2016;48:386-389.

5. Özçakar L (Ed). Sonographic atlas for common musculo- skeletal pathologies. Milan: Edi.Ermes, 2017.

The utility of ultrasound examination in cubital tunnel syndrome caused by heterotopic ossification

Jakub Jačisko


, Karolína Sobotová


, Kamal Mezian


1Department of Rehabilitation and Sports Medicine, Second Faculty of Medicine, Charles University and University Hospital Motol, 2Department of Rehabilitation Medicine, Charles University, First Faculty of Medicine and General University Hospital in Prague, Czech Republic

Received 16.01.2020 Accepted 23.01.2020 Med Ultrason

2020, Vol. 22, No 1, 117-118, DOI: 10.11152/mu-2419, Corresponding author: Jakub Jačisko, MD

Department of Rehabilitation and Sports Medicine, Second Faculty of Medicine, Charles University and University Hospital Motol, V Úvalu 84 150 06 Prague, Czech Republic Phone: 00420776246648

E-mail: [email protected]

To the Editor,

A 65-year-old man presented with a one-year history of bilateral paresthesia of the ulnar side of the forearm and 4th to 5th finger, accompanied by numbness and weakness

of the mentioned area. The patient also reported sleep disturbance due to tingling sensations in his hand and fin- gers, resulting in awakening 3-4 times per night. His his- tory involved 30 years working with a vibrating sander.

Clinical examination revealed hypotrophy of the in- terosseous muscles. Tinel’s test was positive only over the ulnar nerve in the right ulnar sulcus area. Electromyo- graphy and nerve conduction studies revealed bilateral cubital tunnel syndrome, more severe on the right side.

Ultrasound (US) examination of both elbows showed a hyperechoic mass causing acoustic shadowing, in close contact with the ulnar nerve on the right side. The ulnar nerve was swollen bilaterally (right side, cross-section- al area 15 mm2; left side 11 mm2). Radiographs of the


Extensor digitorum brevis manus is uncommon but can easily be misinterpreted during wrist ultrasound examination

Ke-Vin Chang


, Wei-Ting Wu


, Ruei-Fang Wang


, Levent Özçakar


1Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Bei Hu Branch and National Taiwan University College of Medicine, Taipei, Taiwan, 2Department of Emergency Medicine, Taipei City Hospital, Ranai Branch, Taipei, Taiwan, 3Department of Physical and Rehabilitation Medicine, Hacettepe University Medical School, Ankara, Turkey

Received 06.11.2019 Accepted 19.12.2019 Med Ultrason

2020, Vol. 22, No 1, 118-119, DOI: 10.11152/mu-2298, Corresponding author: Ke-Vin Chang, MD, PhD

Department of Physical Medicine and Rehabilitation, National Taiwan University Hospital, Bei-Hu Branch and National Taiwan University College of Medicine, Taipei, Taiwan E-mail: [email protected]

[email protected]

To the Editor

A 37-year-old female complained of a distended sen- sation over her right wrist for the last six months. She reported occasional swelling at its dorsal aspect, accom- panied by only soreness but no pain after 30 minutes of continuous computer use. The medical history was other- wise unremarkable.

elbows showed multiple ossifications of the soft tissue around the medial and lateral humeral epicondyles bi- laterally (fig 1). The patient was informed of the treat- ment options (corticosteroid injection/consideration of surgery) and opted for corticosteroid injection. The ulnar nerve on the right side was injected under US guidance with a mixture of 40 mg (1 ml) methylprednisolone and 1 ml 1% trimecaine. The injection provided satisfactory pain relief at the 2-week and 3-month follow-up.

The utility of US examination is found not only in di- agnostic, but also in providing accurate therapy and fol- Fig 1. Left side: Ultrasound revealed a hyperechoic mass caus- ing acoustic shadowing bilaterally, with close contact to a swol- len ulnar nerve on the right side. D, distal; P, proximal; JG, joint gap; ME, medial epicondyle; white arrow, swollen ulnar nerve;

asterisk, heterotopic ossification. Right side: Anteroposterior radiographs of both elbow joints. White arrows, heterotopic os- sifications; L, left; R, right.

low-up. US examination can provide information about ulnar nerve morphology and surrounding structures that can be the cause of compression [1].Therapeutic injec- tion under US control is more precise and targeted. Dur- ing follow-up, US examination can be a very useful tool for evaluating therapeutic effect - in this particular case, a reduction in the cross-sectional area of the swollen nerve.

Heterotopic ossification (HO) is a pathologic forma- tion of bone within soft tissues. The main risk factors for HO are orthopedic surgery, trauma, brain or spinal cord injury and severe burns. Repetitive mechanical stress or microtrauma is generally thought to be present among the rest of the patients [2]. The long history of working with a vibrating sander in our patient was, probably, the risk factor for HO. More studies about HO in patients exposed to occupational vibration are needed.

Acknowledgment: This study was supported by the Foundation “Movement without Help”, Prague, Czech Republic.


1. Kara M, Yalçın S, Yenigün D, Tiftik T, Malas FÜ, Özçakar L. Heterotopic ossification and cubital tunnel syndrome in traumatic brain injury: Ultrasound ‘sees’ both. J Back Mus- culoskelet Rehabil 2015;28:415-417.

2. Meyers C, Lisiecki J, Miller S, et al. Heterotopic Ossifica- tion: A Comprehensive Review. JBMR Plus. 2019;3:e10172.



Med Ultrason 2020; 22(1): 114-119 She was referred for an ultrasound (US) examination

of the wrist. Pre-scanning physical examination revealed no tenderness and normal wrist motions. The transducer was first placed in the transverse plane at the ulnar styloid level. A hypoechoic mass was visualized between the ex- tensor indicis (EI)and extensor digitorum communis ten- dons (fig 1A). Power Doppler imaging showed increased intralesional vascularity. Additionally, a ganglion cyst was seen emerging from the joint between the capitate and scaphoid. The transducer was then pivoted to the lon- gitudinal plane and several parallel hyperechoic striates were seen inside the mass (fig 1B). We asked the patient to flex and extend the wrist and found out that the mass had a synchronized movement with finger extensor ten- dons (Supplementary Video 1, on the journal site). As a similar mass/structure was also identified at the contralat- eral wrist, she was considered to have bilateral extensor digitorum brevis manus (EDBM) muscles (fig 1C). We advised her to avoid any overuse of the wrist and gave instructions regarding the proper ergonomics for using electronic gadgets.

The EDBM is an accessory muscle inside the fourth extensor compartment of the dorsal wrist [1]. It usually emanates from the radiocarpal joint capsule and inserts distally on the EI tendon or the extensor hooks of middle, ring and little fingers. It receives innervation and vascular supply from the posterior interosseous nerve and artery, respectively. Its prevalence is around 2.3% in the general population based on a previous meta-analysis [2]. Par- ticipants with EDBM muscles are mostly asymptomatic and up to 50% of them have bilateral EDBM [1].

Of note, the existence of the EDBM muscle may in- crease the intra-compartmental pressure, leading to com- pression of the posterior interosseous nerve. In our case, concomitant presence of the EDBM muscle and the gan- glion cyst further congested the compartment. Therefore, after repetitive wrist movements, the blood flow to the EDBM muscle increased, resulting in a distension feel- ing due to muscle edema.

Undoubtedly, US imaging is useful for the diagnosis of several wrist pathologies [3,4]. However, once unfa- miliar with its presence, the EDBM muscle can easily/

likely be interpreted as a hypervascular tumor originating from the finger extensor tendon sheath- especially in the axial plane. During longitudinal imaging, its echotexture can be better clarified i.e. multiple hyperechoic lines un-

Fig 1. Ultrasound imaging of the extensor digitorum brevis manus muscle (white/black dashed area) in the transverse (A) and longitudinal (B) views. Schematic drawing (C). EDC, ex- tensor digitorum communis tendon; EI, extensor indicis ten- don; asterisks, ganglion cyst

der a hypoechoic background are consistent with perimy- sium in a muscle. Importantly, the synchronized move- ment with adjacent finger extensor tendons (on dynamic imaging) and bilateral presence (on comparative imag- ing) further confirmed the mass/structure to be an acces- sory muscle. In short, this report highlighted a relatively rare muscle variation on the dorsal hand, which should not be misinterpreted as a pathological finding during (a convenient but comprehensive) wrist US examination.

Acknowledgment: The present study is supported by the National Taiwan University Hospital, Bei-Hu Branch, Ministry of Science and Technology (MOST 106-2314-B-002-180-MY3) and Taiwan Society of Ul- trasound in Medicine.


1. Shereen R, Loukas M, Tubbs RS. Extensor Digitorum Bre- vis Manus: A Comprehensive Review of this Variant Mus- cle of the Dorsal Hand. Cureus 2017;9:e1568.

2. Yammine K. The prevalence of extensor digitorum brevis manus and its variants in humans: a systematic review and meta-analysis. Surg Radiol Anat 2015;37:3-9.

3. Wu WT, Chang KV, Mezian K, et al. Ulnar Wrist Pain Revisited: Ultrasound Diagnosis and Guided Injection for Triangular Fibrocartilage Complex Injuries. J Clin Med 2019;8:E1540.

4. Chang KV, Wu WT, Özçakar L. Ultrasound Imaging for Dorsal Ulnar Cutaneous Neuropathy With Exten- sor Carpi Ulnaris Tendinopathy. Am J Phys Med Rehabil 2017;96:e191-e192.



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