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Compressive Neuropathy of the Deep Motor Branch of the Ulnar Nerve in Amateur Cyclist
Korean J Sports Med 2020;38:234-237
Published online December 1, 2020;  https://doi.org/10.5763/kjsm.2020.38.4.234
© 2020 The Korean Society of Sports Medicine.

Jae Jun Nam1, In Cheul Choi1, Ji Hun Park2, Jong Woong Park1

1Department of Orthopaedics, Korea University Anam Hospital, Seoul,
2Department of Orthopaedics, Korea University Guro Hospital, Seoul, Korea
Correspondence to: In Cheul Choi
Department of Orthopaedics, Korea University Anam Hospital, 13 Jongam-ro, Seongbuk-gu, Seoul 02841, Korea
Tel: +82-2-920-6995, Fax: +82-2-924-2471
E-mail: indolldr@korea.ac.kr
Received July 21, 2020; Revised October 9, 2020; Accepted October 27, 2020.
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
 Abstract
A 36-year-old female amateur cyclist developed mononeuropathy of the deep branch of the ulnar nerve due to nerve compression adjacent to the ulnar tunnel (type II Guyon’s canal syndrome) caused by prolonged bicycle riding. The patient’s signs and symptoms persisted even after refraining from cycling for 4 weeks; thus, she underwent decompression of the deep branch of the ulnar nerve in the palm and wrist. Three months postoperation, she recovered nearly full power and function of her left hand.
Keywords : Cyclist palsy, Motor branch of ulnar nerve, Type II Guyon’s canal syndrome
μ„œ λ‘ 

μ²™κ³¨κ΄€λ‚΄μ—μ„œ μ²™κ³¨μ‹ κ²½μ˜ 압박은 λ‹€μ–‘ν•œ 원인듀이 보고되고 μžˆλ‹€. 주둜 외상에 μ˜ν•œ κ²°μ ˆμ’…μ΄λ‚˜ 지방쒅 λ“±μ˜ 곡간 점유 λ³‘μ†Œμ— μ˜ν•˜κ±°λ‚˜1 반볡적인 외상 등에 μ˜ν•œ κ°€μ„± 동λ§₯λ₯˜, 척골 동λ§₯λ‚΄λΆ€μ˜ ν˜ˆμ „μ¦, μ†Œμ§€κ΅¬ λ§μΉ˜μ¦ν›„κ΅°2 등이 보고되고 μžˆλ‹€. 이외에도 κ³Όλ„ν•œ μš΄λ™μ— μ˜ν•΄ μ›μœ„ μ²™κ³¨κ΄€μ—μ„œμ˜ 압박은 감각신경은 보쑴되고 μš΄λ™μ‹ κ²½μΈ μ²™κ³¨μ‹ κ²½μ˜ 심뢀 λΆ„μ§€λ§Œ μ••λ°•λ˜λŠ” 제2ν˜•μ˜ 척골관 증후ꡰ이 유발될 수 μžˆλ‹€3. μ €μžλ“€μ€ 사이클 λ™ν˜ΈμΈμ—κ²Œμ„œ λ°œμƒν•œ 제2ν˜• 척골관 증후ꡰ을 κ²½ν—˜ν•˜μ˜€μœΌλ©°, 수술적 치료λ₯Ό 톡해 μž„μƒμ μœΌλ‘œ 쒋은 κ²°κ³Όλ₯Ό μ–»μ—ˆκΈ°μ— λ³΄κ³ ν•˜λŠ” 바이닀.

증 λ‘€

λ³Έ μž„μƒμ—°κ΅¬λŠ” ν™˜μžμ˜ μ§„λ£Œκ³Όμ • 쀑에 발견된 증둀λ₯Ό λ³΄κ³ ν•˜λŠ” κ²ƒμœΌλ‘œ λ³΄κ³ μ„œ μž‘μ„±ν•˜λŠ” κ³Όμ •μ—μ„œ ν™˜μžμ—κ²Œ μΆ”κ°€λ‘œ μœ„ν•΄κ°€ κ°€ν•΄μ§€λŠ” 일은 μ—†μœΌλ―€λ‘œ ν™˜μžμ—κ²Œ λ”°λ‘œ μ„œλ©΄λ™μ˜λ‚˜ IRB μŠΉμΈμ€ 받지 μ•Šμ•˜λ‹€.

36μ„Έ μ—¬μž ν™˜μžλ‘œ 3κ°œμ›”μ „ μ‹œμž‘λœ 쒌츑 μˆ˜λΆ€μ˜ κ·Όλ ₯μ•½ν™”λ₯Ό ν˜Έμ†Œν•˜λ©° λ‚΄μ›ν•˜μ˜€λ‹€. ν™˜μžλŠ” μ£ΌλΆ€λ‘œ νŠΉλ³„ν•œ 외상λ ₯은 μ—†μ—ˆμœΌλ‚˜ μ•½ 5κ°œμ›”μ „λΆ€ν„° 사이클 λ™ν˜ΈνšŒμ—μ„œ ν™œλ™μ„ μ‹œμž‘ν•˜μ˜€κ³  맀일 3μ‹œκ°„μ”© μžμ „κ±° 타기λ₯Ό ν•˜μ˜€λ‹€. 신체검사상 쒌츑 μˆ˜μ§€μ˜ κ°κ°μ €ν•˜λŠ” μ—†μ—ˆμœΌλ‚˜ μˆ˜λΆ€ λ‚΄μž¬κ·Ό μœ„μΆ•μ΄ λšœλ ·ν•˜μ˜€κ³ (Fig. 1) κ·Όλ ₯은 λ¬΄μ§€μ˜ μ§‘κ²Œλ ₯을 κΈ°μ€€μœΌλ‘œ 건츑이 20 lb, ν™˜μΈ‘μ΄ 7.5 lb둜 건츑과 λΉ„κ΅ν•˜μ—¬ μ•½ 40% μˆ˜μ€€μœΌλ‘œ κ°μ†Œλ˜μ–΄ μžˆμ—ˆλ‹€. μˆ˜κ·ΌλΆ€ μ£Όλ³€μ—μ„œ Tinel μ†Œκ²¬μ€ κ΄€μ°°λ˜μ§€ μ•Šμ•˜κ³  Froment κ²€μ‚¬λŠ” μ–‘μ„±μ΄μ—ˆλ‹€. λ‹¨μˆœλ°©μ‚¬μ„  검사상 μˆ˜κ·ΌλΆ€μ˜ 골절 λ“±μ˜ μ΄μƒμ†Œκ²¬μ€ κ΄€μ°°λ˜μ§€ μ•Šμ•˜μœΌλ©° 전기생리검사상 μ‹ κ²½μ „λ„κ²€μ‚¬μ—μ„œ 척골관 μ£Όλ³€μ—μ„œ 볡합근 ν™œλ™μ „μœ„μ˜ 잠볡기 및 전도속도가 μ§€μ—°λ˜μ–΄ μžˆμ—ˆκ³  감각신경 ν™œλ™μ „μœ„λŠ” μ •μƒμ†Œκ²¬μ„ λ³΄μ˜€λ‹€. 근전도 κ²€μ‚¬μƒμ—μ„œ 제1λ°°μΈ‘ 골간근과 μ†Œμ§€ μ™Έμ „κ·Όμ—μ„œ 비정상 자발적 ν™œλ™μ „μœ„μ™€ κ°μ†Œλœ μš΄λ™λ‹¨μœ„ ν™œλ™μ „μœ„κ°€ ν™•μΈλ˜μ—ˆλ‹€(Table 1).

Table 1 . Study of NCV and EMG

VariableResult
NCV
MuscleStimulation siteLatency (msec)Amplitude (mV)
ADMWrist6.6 (Prolonged)4.0 (Reduced)
FDIDWC4.12.2 (Marked Reduced)
Needle EMG
MuscleInsertional activitySpontaneous activityMUAP (duration)RP
ADMIIAF&P (οΌ‹)LongR
FDIIIAF&P (οΌ‹οΌ‹)LongMarkedly R

NCV: nerve conduction velocity, EMG: electromyography, ADM: abductor digiti minimi, FDI: first dorsal interossei, DWC: distal wrist crease, MUAP: motor unit action potentials, RP: recruitment pattern, F&P: fibrillation potentials and positive sharp waves, R: reduced.


Fig. 1. Clinical photography showing the hypotrophy of the first dorsal interosseous muscle (arrow) of the left hand.

μ €μžλ“€μ€ ν™˜μžμ—κ²Œ 병인에 λŒ€ν•΄ μ„€λͺ… ν›„ μ²™κ³¨μ‹ κ²½μ˜ μš΄λ™λΆ„μ§€κ°€ μ••λ°•λ˜λŠ” κ³Όλ„ν•œ μžμ „κ±° 타기 μš΄λ™μ„ μ€‘λ‹¨ν•˜λ„λ‘ κΆŒκ³ ν•˜μ˜€λ‹€. κ·ΈλŸ¬λ‚˜ ν™˜μžμ˜ 증상은 μš΄λ™ 쀑단 후에도 μ•…ν™” μ§„ν–‰λ˜λŠ” μ†Œκ²¬μ„ λ³΄μ˜€κ³  μ €μžλ“€μ€ 수술적 치료둜 κ°μ••μˆ μ„ κ³„νšν•˜μ˜€λ‹€. 수술 μ „ μ‹œν–‰ν•œ 초음파 검사상 쒌츑 척골관 μ›μœ„λΆ€, μ†Œμ§€κ·Όκ΅¬μ˜ μ„¬μœ μ„± 근막 ν•˜λ°©μ—μ„œ μ²™κ³¨μ‹ κ²½μ˜ 심뢀 뢄지인 μš΄λ™μ‹ κ²½ 뢄지가 건츑과 λΉ„κ΅ν•΄μ„œ λΉ„λŒ€λ˜μ–΄ μžˆλŠ” μ†Œκ²¬μ„ ν™•μΈν•˜μ˜€λ‹€(Fig. 2). μˆ˜μˆ μ€ 손λͺ© μ²™μΈ‘ ꡴곑 μ£Όλ¦„μ—μ„œ μ²™κ³¨κ΄€μ˜ μ›μœ„λΆ€κΉŒμ§€ ν”ΌλΆ€ 절개λ₯Ό μ‹œν–‰ν•˜μ—¬ μ²™κ³¨μ‹ κ²½μ˜ ν‘œμž¬μ„± 뢄지와 심뢀 뢄지λ₯Ό ν™•μΈν•˜κ³  μ†Œμ§€κ·Όκ΅¬μ˜ μ„¬μœ μ„± 근막을 μ ˆκ°œν•˜μ—¬ 심뢀 뢄지λ₯Ό κ°μ••ν•˜μ˜€λ‹€(Fig. 3).

Fig. 2. Ultrasonography showing the larger diameter of the ulnar nerve motor branch (circles) of the left hand than the right hand (left side arrow), underneath the fibrotic fascial band of hypothenar muscle (asterisks). (A) Right wrist. (B) Left wrist.
Fig. 3. (A) An intraoperative view of the thickened hypothenar muscle (asterisk) compressing the deep motor branch of ulnar nerve. (B) After releasing the hypothenar muscle (asterisk) fascia, the motor branch of ulnar nerve (arrow) can be found.

수술 ν›„ 1주일 λ™μ•ˆ 단상지 λΆ€λͺ©κ³ μ •μ„ μ μš©ν•˜μ˜€κ³  이후 κ΄€μ ˆμš΄λ™κ³Ό μΌμƒμƒν™œμ„ ν—ˆλ½ν•˜μ˜€λ‹€. ν™˜μžλŠ” 수술 ν›„ 1κ°œμ›”λΆ€ν„° 주관적인 κ·Όλ ₯ νšŒλ³΅μ„ λŠλ‚„ 수 μžˆμ—ˆλ‹€κ³  ν•˜μ˜€κ³  수술 ν›„ 3κ°œμ›”μ§Έμ—λŠ” 외견상 μœ„μΆ•λ˜μ—ˆλ˜ 근윑의 νšŒλ³΅μ„ 확인할 수 μžˆμ—ˆκ³ (Fig. 4) 신체검사상 λ¬΄μ§€μ˜ μ§‘κ²Œλ ₯이 수술 μ „ 7.5 lbμ—μ„œ 13 lb둜 νšŒλ³΅λ˜μ—ˆμœΌλ©° 수술 ν›„ 4κ°œμ›”μ§Έ μ‹œν–‰ν•œ 전기생리검사상 신경전도검사와 근전도 κ²€μ‚¬μƒμ—μ„œ 수술 μ „ μ΄μƒμ†Œκ²¬μ„ 보이던 μˆ˜μΉ˜λ“€μ΄ μ •μƒν™”λœ 것을 ν™•μΈν•˜μ˜€λ‹€.

Fig. 4. Clinical photography at 3 months postoperation showing recovery of the first dorsal interosseous muscle (arrow) on the left hand.
κ³  μ°°

척골신경은 κ²°μ ˆμ’…μ΄λ‚˜ 지방쒅 λ“±μ˜ 곡간 점유 λ³‘μ†Œ, 이상 근윑, 외상 λ“± λ‹€μ–‘ν•œ 원인에 μ˜ν•΄ μ²™κ³¨κ΄€λ‚΄μ—μ„œ 압박될 수 있고1,2,4, 특히 μ›μœ„ μ²™κ³¨κ΄€λ‚΄μ—μ„œ μš΄λ™μ‹ κ²½λΆ„μ§€μΈ μ‹¬λΆ€λΆ„μ§€λ§Œ μ••λ°•λ˜λ©΄ 감각 신경증상은 μ—†κ³  λ‚΄μž¬κ·Όμ˜ κ·Όλ ₯μ•½ν™”κ°€ μ£Ό 증상인 제2ν˜• 척골관 μ¦ν›„κ΅°μœΌλ‘œ λΆ„λ₯˜ν•œλ‹€5. λ˜ν•œ 척골신경 심뢀뢄지가 μ••λ°•λ˜λŠ” μœ„μΉ˜μ— λ”°λΌμ„œ λ‹€μ–‘ν•œ ν˜•νƒœλ‘œ λ‚΄μž¬κ·Όμ˜ κ·Όμœ„μΆ•μ΄ 유발될 수 μžˆλ‹€κ³  보고되고 μžˆλ‹€6.

졜근 건강을 μœ„ν•œ 슀포츠 인ꡬ가 μ¦κ°€ν•˜λ©΄μ„œ κ³Όκ±° 전문적인 μš΄λ™μ„ μˆ˜λ“€μ—κ²Œμ„œλ§Œ μ§„λ‹¨λ˜μ—ˆλ˜ μ§ˆν™˜λ“€μ΄ 일반 λ™ν˜ΈμΈμ—κ²Œμ„œλ„ λ‚˜νƒ€λ‚˜κ³  μžˆλ‹€. μ‚¬μ΄ν΄μ„ μˆ˜ λ§ˆλΉ„λŠ” μ „ν˜•μ μΈ μš΄λ™μžμ„Έμ™€ μ†μž‘μ΄ ν˜•νƒœμ— μ˜ν•΄ μ²™κ³¨μ‹ κ²½μ˜ 심뢀 λΆ„μ§€μ—μ„œλ§Œ 압박이 μΌμ–΄λ‚˜λŠ” 제2ν˜•μ˜ 척골관 증후ꡰ이닀3. μ•žμ— λ‚˜μ—΄ν–ˆλ˜ μ—¬λŸ¬ μ›μΈλ“€μ²˜λŸΌ μ˜μƒ 진단 검사상 ν˜•νƒœμ μΈ λ³€ν™”κ°€ λšœλ ·ν•˜μ§€ μ•ŠκΈ° λ•Œλ¬Έμ— μ„Έλ°€ν•œ 병λ ₯μ²­μ·¨λ₯Ό ν†΅ν•œ μž„μƒμ  μ˜μ‹¬κ³Ό ν•¨κ»˜ μˆ™λ ¨λœ μž¬ν™œμ˜ν•™ ν˜Ήμ€ μ‹ κ²½κ³Ό μ „λ¬Έμ˜μ˜ 전기생리검사가 μ‹œν–‰λ˜μ–΄μ•Ό ν•œλ‹€. λ³Έ μ¦λ‘€μ˜ ν™˜μžλ„ μ΄ˆμ§„ μ‹œμ—λŠ” 병λ ₯청취상 μš΄λ™λ ₯이 κ°„κ³Όλ˜μ—ˆλ‹€κ°€ 좔후에 과도할 μ •λ„μ˜ μžμ „κ±° νƒ€κΈ°μ˜ μš΄λ™λ ₯이 ν™•μΈλœ κ²½μš°μ΄λ‹€.

μΌμ‹œμ μΈ κ³Όλ„ν•œ μš΄λ™μ— μ˜ν•΄ 유발된 μ‹ κ²½ 병변은 μš΄λ™μ˜ 쀑지, μžμ„Έκ΅μ • λ“±μ˜ 보쑴적 치료둜 증상 ν˜Έμ „μ΄ μ˜ˆμƒλœλ‹€. 사이클 ν•Έλ“€μ˜ ν˜•νƒœμ™€ μ°©μš©ν•˜λŠ” μž₯κ°‘μ˜ λ‘κ»˜μ— λ”°λ₯Έ 척골관 주변에 κ°€ν•΄μ§€λŠ” μ••λ ₯의 변화에 λŒ€ν•œ 연ꡬ가 λ³΄κ³ λ˜μ–΄ μžˆλ‹€7. Hankey와 Gubbay3도 μ‚¬μ΄ν΄μ„ μˆ˜ λ§ˆλΉ„ 증둀λ₯Ό λ³΄κ³ ν•˜λ©΄μ„œ μ‚¬μ΄ν΄μ˜ μ†μž‘μ΄ 그립의 λ³€κ²½λ§ŒμœΌλ‘œ 증상이 ν˜Έμ „λœ 증둀λ₯Ό λ³΄κ³ ν•˜μ˜€λ‹€. κ·ΈλŸ¬λ‚˜ 보쑴적 치료 λ°©λ²•μœΌλ‘œ 증상이 ν˜Έμ „λœ μ¦λ‘€λŠ” μž„μƒμ  증상이 κ²½λ―Έν•˜μ˜€κ³  전기생리검사상 νƒˆμ‹ κ²½ λ³€ν™”λŠ” μ‹¬ν•˜μ§€ μ•Šμ•˜λ‹€. ν•¨κ»˜ 보고된 수술적 μΉ˜λ£Œκ°€ ν•„μš”ν–ˆλ˜ 또 λ‹€λ₯Έ μ¦λ‘€μ—μ„œλŠ” μš΄λ™ 쀑단을 ν¬ν•¨ν•œ 보쑴적 μΉ˜λ£Œμ— μ¦μƒν˜Έμ „μ΄ μ—†μ—ˆκ³  전기생리검사상 λšœλ ·ν•œ νƒˆμ‹ κ²½ μ†Œκ²¬μ΄ ν™•μΈλœ μ¦λ‘€μ˜€λ‹€. λ³Έ μ¦λ‘€μ˜ ν™˜μžμ—μ„œλ„ μž„μƒμ¦μƒμ˜ μ•…ν™”κ°€ 진행 μ€‘μ΄μ—ˆκ³  수술 전에 μ‹œν–‰ν–ˆλ˜ μ „κΈ°μƒλ¦¬κ²€μ‚¬μƒμ—μ„œ 제1λ°°μΈ‘ 골간근과 μ†Œμ§€ μ™Έμ „κ±΄μ—μ„œ 진행성 λ§Œμ„± νƒˆμ‹ κ²½ μ†Œκ²¬μ„ λ³΄μ˜€λ‹€. λ‹€λ₯Έ μ••λ°•μ„± μ‹ κ²½ λ³‘λ³€μ—μ„œμ™€ λ§ˆμ°¬κ°€μ§€λ‘œ κ³ ν•΄μƒλ„μ˜ 초음파λ₯Ό 톡해 척골관 μ›μœ„λΆ€μ—μ„œ μ²™κ³¨μ‹ κ²½μ˜ μš΄λ™λΆ„μ§€μ˜ 주행을 따라 μ΄μƒμ†Œκ²¬μ„ κ΄€μ°°ν•  수 있고8 반볡적인 μžκ·Ήμ— μ˜ν•œ μ‹ κ²½μ˜ 직경을 건츑과 λΉ„κ΅ν•˜κ±°λ‚˜ 초음파 μƒμ˜ 저에코(hypoechoic) λ³€ν™” λ“±μœΌλ‘œ ν•΄λ‹Ή μ‹ κ²½μ˜ λΆ€μ’… μ—¬λΆ€λ₯Ό ν™•μΈν•˜λŠ” 것은 전기생리검사와 ν•¨κ»˜ 진단에 μœ μš©ν•˜λ‹€.

λ³Έ μ¦λ‘€μ—μ„œλ„ 전기생리검사 후에 μ‹œν–‰ν•œ 초음파 μƒμ—μ„œ 척골관 μ›μœ„λΆ€ μ†Œμ§€κ·Όμ˜ 기원 κ·Όλ§‰μ˜ μ‹¬λΆ€μ—μ„œ ν•΄λ‹Ή μ‹ κ²½μ˜ λΉ„λŒ€λ₯Ό 건츑과 λΉ„κ΅ν•˜μ—¬ 확인할 수 μžˆμ—ˆλ‹€. μž„μƒμ˜λŠ” μ „λ¬Έ μš΄λ™μ„ μˆ˜λΏ μ•„λ‹ˆλΌ 일반 λ™ν˜ΈμΈμ—μ„œλ„ 단기간 κ³Όλ„ν•œ μš΄λ™μœΌλ‘œ μ‚¬μ΄ν΄μ„ μˆ˜ λ§ˆλΉ„μ— ν•΄λ‹Ήν•˜λŠ” 제2ν˜•μ˜ 척골관 증후ꡰ이 생길 수 μžˆμŒμ„ μ£Όμ§€ν•˜μ—¬μ•Ό ν•œλ‹€. λ˜ν•œ 제2ν˜•μ˜ 척골관 증후ꡰ은 비ꡐ적 λ“œλ¬Έ μ••λ°•μ„± μ‹ κ²½λ³‘μ¦μ΄μ§€λ§Œ μ„Έμ‹¬ν•œ 병λ ₯청취와 신체검사, 전기생리검사λ₯Ό 톡해 진단할 수 있고 보쑴적 μΉ˜λ£Œμ— λ°˜μ‘ν•˜μ§€ μ•Šμ„ 경우 μ‘°κΈ° κ°μ••μˆ μ„ 톡해 λΉ λ₯Έ κ·Όλ ₯의 νšŒλ³΅μ„ κΈ°λŒ€ν•  수 μžˆμ„ κ²ƒμœΌλ‘œ μƒκ°ν•œλ‹€.

Conflict of Interest

No potential conflict of interest relevant to this article was reported.

Author Contributions

Conceptualization: ICC. Methodology: JHP. Writing–original draft: JJN. Writing–review & editing: JWP.

References
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