Percutaneous Ultrasound-Guided Release of the Transverse Carpal Ligament Versus Open Surgery for Carpal Tunnel Syndrome: A Prospective Comparative Study
Phase: NA
Conditions: Carpal Tunnel Syndrome (CTS)
Sponsor: Fundacin Biomedica Galicia Sur

Date: December 1, 2020 
STUDY TITLE 
 
 
ULTRASOUND-GUIDED PERCUTANEOUS 
TRANSVERSE CARPAL LIGAMENT SECTION VS 
OPEN SURGERY FOR THE SURGICAL 
TREATMENT OF CARPAL TUNNEL SYNDROME 
(CTS).  
 
 
 
 
 
 
 

Date: December 1, 2020 
INDEX 
 
1. 
COVER....................................................................................................................... 1 
2. 
INDEX.........................................................................................................................2 
3. SUMMARY ............................................................................................................ 3 
4. BACKGROUND AND JUSTIFICATION OF THE STUDY..................................................4 
5. STUDY HYPOTHESIS................................................................................................5 
6. SPECIFIC AND SECONDARY OBJECTIVES OF THE STUDY............................................6 
7. DESIGN AND METHODS...........................................................................................6 
8. ETHICAL AND LEGAL ASPECTS............................................................................... 11 
9. IMPLEMENTATION PLAN.......................................................................................12 
10. FINANCIAL REPORT / SOURCE OF FINANCING..................................................... 13 
11. 
BIBLIOGRAPHY.........................................................................................................13 
12.- Annex 1............................................................................................................. 16 
 
 

Date: December 1, 2020 
 
 
 
3. SUMMARY 
• Title of the project: ULTRASOUND-GUIDED PERCUTANEOUS TRANSVERSE CARPAL 
LIGAMENT SECTION VS OPEN SURGERY FOR THE SURGICAL TREATMENT OF CARPAL 
TUNNEL SYNDROME (CTS). 
• Principal investigator.  
- Manuel Castro Menéndez. F.E.A. Orthopaedic Surgery and Traumatology. University 
Hospital Complex of Vigo. 
• Centres where the study is planned to be carried out. University Hospital Complex of 
Vigo 
• Design. Prospective observational cohort study. 
• Main and secondary objectives: To analyze the functional outcome of patients 
operated on for carpal tunnel syndrome (CTS) in a percutaneous ultrasound-guided 
manner and compare it with the results obtained by open surgery. 
• Primary endpoint: Clinical and functional improvement using a specific questionnaire 
for CTS: Boston Carpal Tunnel Syndrome Questionnaire (BCTQ).  
• Population under study and total number of patients: Patients from the CHUVI 
Health Area who have been diagnosed with Carpal Tunnel Syndrome and are going to 
undergo surgery at the centre from 1 February 2021 to 31 December 2021 by doctors 

Date: December 1, 2020 
specialising in Orthopaedic Surgery and traumatology belonging to the CHUVI Upper 
Limb Unit. 
• Duration of patient enrollment: From January 1, 2021 to January 31, 2024 (or until 
the calculated sample size is completed). 
• Calendar and expected date of completion of the study: Febrary 2024 end of 
collection; between April and May 2024 analysis and dissemination of results. 
 
4. BACKGROUND AND JUSTIFICATION OF THE STUDY 
Surgical treatment for carpal tunnel syndrome consists of the transverse carpal ligament 
(LTC) section. The section of this ligament is usually done through a palmar skin incision. 
This technique is a common, simple, safe and effective procedure for the treatment of 
this pathology, but it is not exempt from complications such as the presence of painful 
palm scars, prolonged pain in the incision area, fatigue or weakness of the hand, 
periincisional pain (pillar pain) or prolonged convalescence time -return to previous 
activities-1-3.  
To try to minimize complications, percutaneous techniques have been developed. With 
these procedures, by not making an open incision through the palm, it is expected that 
the incidence of discomfort and tenderness in the palmar area will be reduced. In 
addition, it is also expected that there will be a decrease in postoperative morbidity, less 
time to return to work, and greater recovery of grip strength when this technique is 
used1,4-7. However, its risk-benefit ratio compared to that of open release remains 
controversial8-12. The risks to adjacent neurovascular structures inherent in these 

Date: December 1, 2020 
percutaneous techniques remain one of the main factors preventing the acceptance of 
this technique4,13-15.  
To minimize these risks, ultrasound has been used as a guide when performing these 
percutaneous techniques, since ultrasound makes it possible to perfectly visualize carpal 
tunnel 
structures 
when 
performing 
this 
release1,12,16-18. 
Ultrasound-guided 
percutaneous carpal tunnel release is a minimally invasive technique that has been 
developed over the last 20 years and has been shown to be effective and safe in several 
studies 1,8,19-21.  
In our department, doctors from the Upper Limb Unit regularly use ultrasound for the 
diagnosis of upper limb pathology, as well as to perform local blocks when performing 
procedures under local anaesthesia. Due to the practice achieved with these 
procedures, ultrasound is being used as a support in other procedures such as the 
localization of foreign bodies, percutaneous release of CTS or the release of trigger 
fingers. 
The aim of this study is to assess whether percutaneous release of the carpal tunnel 
guided by ultrasound provides, in our experience, more benefits than performing it 
through a short palmar incision. 
 
5. HYPOTHESIS OF THE STUDY 
Opening of the transverse carpal ligament percutaneously ultrasound-guided for the 
surgical treatment of carpal tunnel syndrome (CTS) has better results than opening by 
open surgery (palmar incision). 

Date: December 1, 2020 
6. SPECIFIC AND SECONDARY OBJECTIVES OF THE STUDY 
Main objective:  
To analyze the functional results of  the surgical treatment of CTS using percutaneous 
ultrasound-guided technique and to compare them with the results obtained by open 
surgery with a palmar incision. 
Secondary objective:  
To analyze the presence of complications (scar pain, pillar pain) and the pre- and 
postoperative difference in manual grip strength (measured with a JAMAR manual 
dynamometer) of surgical treatment of CTS using percutaneous ultrasound-guided 
technique and compare them with the results obtained by open surgery with a palmar 
incision. 
 
 
7. DESIGN AND METHODS 
Design:  
Prospective observational cohort study. 
Study population:  
Patients in the CHUVI Health Area who have been diagnosed with CTS by a specialist in 
Orthopaedic Surgery and Traumatology at that centre, have undergone surgery for this 
pathology from 1 January 2021 to 31 January 2024, and meet the inclusion and exclusion 
criteria. 

Date: December 1, 2020 
- Inclusion Criteria:  
1.- Patient diagnosed with CTS by clinical examination and confirmed by complementary 
test (Electromyogram). 
2.- Patients over 18 years of age. 
3.- Patients who belong to the CHUVI Health Area. 
4.- Patients with the capacity to consent and who agree to participate by signing the 
informed consent. 
5.- Follow the guidelines and reviews set forth in the Consultation. 
- Exclusion Criteria: 
1- Patient who has previously undergone surgery for the same pathology in the same 
hand (recurrence). 
2.- Patient incapacitated or unable to follow guidelines indicated by the Physician. 
3.- Patient with associated pathology in the same hand for which he/she is going to be 
operated on in the same surgical act. 
4- Patients with the presence of associated synovitis at the level of the flexor tendons of 
the hand to be treated.  
 
- Sample size calculation. 
Based on the study published by Kim et al23, who studied the minimum clinically 
important difference (MCID) for the Boston Carpal Tunnel Syndrome Questionnaire22, 
and accepting an alpha risk of 0.05 and a beta risk of less than 0.2 in a bilateral contrast, 

Date: December 1, 2020 
98 subjects in the first group and 98 in the second group are needed to detect a 
difference equal to or greater than 0.94 units. The common standard deviation is 
assumed to be 1. A follow-up loss rate of 10% has been estimated. 
 
Procedure 
 
Patients from the CHUVI Health Area diagnosed with the explained pathology, who meet 
the inclusion and exclusion criteria, and who are going to undergo surgery at the CHUVI 
by specialist doctors from the Orthopaedic Surgery and Traumatology Service belonging 
to the Upper Limb Unit, will be recruited. These patients will be informed of their 
pathology, and after signing the informed consent, surgery will be performed in the two 
proposed ways:  
 -Procedure A: ultrasound-guided percutaneous surgery.  
-Procedure B: open surgery through a short palmar incision.  
These two forms of surgical treatment are approved and used in our Service. The 
assignment to one or another surgical technique will be made based on the criteria of 
the physician who diagnoses the patient, as he or she does in his or her usual clinical 
practice, once the patient's clinical characteristics, pathology, and preferences have 
been heard. 
Data will be collected from the patients included in the study in the preoperative 
consultation, intraoperatively and in the revision consultations that are usually carried 
out for this pathology 2 weeks after surgery, 6 weeks and 3 months. 
In the preoperative consultation, the following will be collected: 

Date: December 1, 2020 
1.- Grip strength of the hand measured with JAMAR manual dynamometer. 
2.- Score of the specific questionnaire for the pathology of CTS: Boston Carpal Tunnel 
Syndrome Questionnair22 (ANNEX 1). 
Surgery will include: 
1.- Time of surgical intervention 
2.- Use or not of an ischemia cuff to perform surgery. 
In the 2-week postoperative consultation, the following will be assessed: 
1.- State of surgical wound. 
2.- Presence of skin infection or other complication. 
3.- Presence of pillar pain. 
4.- Absence or presence of CTS (paresthesias or pain in the territory of the median 
nerve).  
In the consultations that will be carried out 6 weeks and 3 months after surgery, the 
following will be assessed:  
1.- Surgical incision status. 
2.- Presence of skin infection or other complication. 
3.- Presence of pillar pain. 
4.- Absence or presence of CTS (paresthesias or pain in the territory of the median nerve) 
5.- Grip strength of the hand measured with a JAMAR manual dynamometer. 
6.- Score of the specific questionnaire for the pathology of CTS: Boston Carpal Tunnel 
Syndrome Questionnair22 (ANNEX 1). 

Date: December 1, 2020 
Data recording and management. 
Potential candidates who meet the main characteristic of the study will be offered 
informed consent. Once the consent has been signed, a list of patients who meet the 
inclusion criteria and none of the exclusion criteria will be created.  
The principal investigator (Dr Manuel Castro Menéndez) will be responsible for the 
collection and custody of the data and will ensure that the pseudonymisation of the 
participants is maintained. These will be identified through a code in the CRD and in the 
electronic database, all their information being associated with this code and not with 
their personal data. 
The other members of the team as third parties involved in the statistical analysis of the 
data will only have access to the coded information. 
Statistical analysis. 
A descriptive analysis of the data will be carried out, presenting the qualitative variables 
with their absolute frequency and percentage, and the quantitative variables with their 
mean and standard deviation (SD) or median and percentiles if they do not conform to 
a normal distribution.  
Initially, a univariate analysis will be performed to determine which variables could have 
an independent effect on functional outcomes (grip strength, and the validated 
questionnaire for CTS: Boston Carpal Tunnel Syndrome Questionnaire 22).  
To compare quantitative variables between the two groups, to assess whether there are 
differences and whether they are significant, the normality of the distribution of the 
data in each of the cohorts will be analysed and the parametric t-student test or the 

Date: December 1, 2020 
non-parametric test (Mann-Whitney U) will be applied. For the comparison of the 
qualitative variables between the two cohorts, the Chi-square test will be used.  
Subsequently, including as independent variables those that show significance in the 
univariate analysis or are of clinical interest, they will be included in multivariate 
regression models.  
The data will be analyzed with the SPSS 22.0 Software and 0.05 will be considered as the 
α accepted significance level for all hypothesis tests. 
 
8. ETHICAL AND LEGAL ASPECTS 
Researchers undertake to respect the fundamental principles of the Declaration of 
Helsinki and the Council of Europe Convention on Human Rights and Biomedicine, as 
well as all current legislation related to the study. 
The handling of the study's data, as well as its database, will comply with the 
requirements set out in Regulation (EU) 2016/679 and of the European Parliament and 
of the Council, of 27 April 2016, on the protection of natural persons with regard to the 
processing of personal data and on the free movement of data.  and with Organic Law 
3/2018, of 5 December, on the Protection of Personal Data and guarantee of digital 
rights.  
The staff participating in the study will ensure that the anonymity of the participants is 
maintained. These will be identified through a code in the CRD and in the electronic 
database, all their information being associated with this code and not with their 
personal data. All documents will be stored securely and will only be accessible to 
members of the investigation team and authorized personnel.  

Date: December 1, 2020 
The study protocol and all associated documentation will be submitted for evaluation to 
the Galician ERC Network. Any modifications to the initial approved protocol will be 
forwarded for re-evaluation. 
 
Informed consent  
Study participants must sign an informed consent approved by the Network of Research 
Ethics Committees (CAEI) of Galicia before any of the study procedures are carried out. 
Patients will be provided with a study information sheet and one with informed consent. 
It will be clearly stated that the participant is free to withdraw from the study at any 
time and for any reason without affecting the treatment they will receive in the future 
and without any obligation to explain the reasons for their withdrawal.  
Informed consent will be given to patients in the consultation once they are diagnosed 
with their pathology, meet the inclusion and exclusion criteria, their pathology is 
explained to them and participation in the study is offered. 
 
9. IMPLEMENTATION PLAN 
Inclusion: January 2021 to January 31, 2024. 
Analysis and dissemination: Febrery 2024 to May 2024. 
10. FINANCIAL REPORT / SOURCE OF FUNDING 
The study has been approved by the Head of the Orthopaedic Surgery and Traumatology 
Service of the CHUVI. 
There is no source of funding. 

Date: December 1, 2020 
 
11. BIBLIOGRAPHY 
1.- Tai-Chang Chern, Li-Chieh Kuo, Chung-Jung Shao, Tong-Tai Wu, Kuo-Chen Wu, 
I-Ming Jou. Ultrasonographically Guided Percutaneous Carpal Tunnel Release: Early 
Clinical Experiences and Outcomes. Arthroscopy: The Journal of Arthroscopic & 
Related Surgery, 2015; 31(12): 2400-2410.   
https://doi.org/10.1016/j.arthro.2015.06.023 
2. Buoy H, Ozcan O, Oztekin HH. Long-term complications of open carpal tunnel 
release. Muscle Nerve 2008; 38: 1443-1446. 
3. Kluge W, Simpson RG, Nicol AC. Late complications after open carpal tunnel 
decompression. J Hand Surg 1996; 21: 205-207. 
4. Thoma A, Veltri K, Haines T, Duku E. A meta-analysis of randomized controlled 
trials comparing endoscopic and open carpal tunnel decompression. Plast Reconstr 
Surg 2004;114:1137-1146. 
5. Atroshi I, Larsson GU, Ornstein E, Hofer M, Johnsson R, Ranstam J. Outcomes of 
endoscopic surgery compared with open surgery for carpal tunnel syndrome among 
employed patients: Randomised controlled trial. BMJ 2006;332:1473. 
6. Kang HJ, Koh IH, Lee TJ, Choi YR. Endoscopic carpal tunnel release is preferred 
over mini-open despite similar outcome: A randomized trial. Clin Orthop Relat Res 
2013;471:1548-1554. 
7. Vasiliadis HS, Xenakis TA, Mitsionis G, Paschos N, Georgoulis A. Endoscopic 
versus open carpal tunnel release. Arthroscopy 2010;26:26-33. 
8. Okutsu I, Ninomiya S, Takatori Y, Ugawa Y. Endoscopic management of carpal 
tunnel syndrome. Arthroscopy 1989;5:11-18. 

Date: December 1, 2020 
9. Chow JC. Endoscopic release of the carpal ligament: A new technique for carpal 
tunnel syndrome. Arthroscopy 1989;5:19-24. 
10. Abrams R. Endoscopic versus open carpal tunnel release. J Hand Surg 
2009;34:535-539. 
11. Scholten RJ, Mink van der Molen A, Uitdehaag BM, Bouter LM, de Vet HC. 
Surgical treatment options for carpal tunnel syndrome. Cochrane Database Syst Rev 
2007; (4):CD003905. 
12. Dekimpe C, Andreani O, Camuzard O, Raffaelli C, Petrover D, Foti P, Amoretti 
N. Ultrasound-guided percutaneous release of the carpal tunnel: comparison of the 
learning curves of a senior versus a junior operator. A cadaveric study. Skeletal Radiol. 
2019 Nov; 48(11):1803-1809. DOI: 10.1007/S00256-019-03207-Y. Epub 2019 May 
22. PMID: 31114970. 
13. Vasiliadis HS, Xenakis TA, Mitsionis G, Paschos N, Georgoulis A. Endoscopic 
versus open carpal tunnel release. Arthroscopy 2010;26:26-33. 11. Benson LS, Bare 
AA, Nagle DJ, Harder VS, Williams CS, Visotsky JL. Complications of endoscopic 
and open carpal tunnel release. Arthroscopy 2006;22:919-924.e2.  
14. Boeckstyns ME, Sorensen AI. Does endoscopic carpal tunnel release have a 
higher rate of complications than open carpal tunnel release? An analysis of published 
series. J Hand Surg 1999;24:9-15.  
15. Concannon MJ, Brownfield ML, Puckett CL. The incidence of recurrence after 
endoscopic carpal tunnel release. Plast Reconstr Surg 2000;105:1662-1665. 
16. Tai TW, Wu CY, Su FC, Chern TC, Jou IM. Ultrasonography for diagnosing carpal 
tunnel syndrome: A metaanalysis of diagnostic test accuracy. Ultrasound Med Biol 
2012;38:1121-1128. 

Date: December 1, 2020 
17. Chern TC, Jou IM, Chen WC, Wu KC, Shao CJ, Shen PC. An ultrasonographic 
and anatomical study of carpal tunnel, with special emphasis on the safe zones in 
percutaneous release. J Hand Surg Eur Vol 2009;34:66-71.  
18. Chern TC, Wu KC, Huang LW, et al. A cadaveric and preliminary clinical study 
of ultrasonographically assisted percutaneous carpal tunnel release. Ultrasound Med 
Biol 2014;40:1819-1826. 
19.Lecoq B, Hanouz N, Morello R, et al. Ultrasound-assisted surgical release of carpal 
tunnel syndrome: results of a pilot open-label uncontrolled trial conducted outside the 
operating 
theatre. 
Joint 
Bone 
Spine. 
2015; 
82(6):442–5. 
https://doi.org/10.1016/j.jbspin. 2015.01.024.  
20. Petrover D, Silvera J, De Baere T, Vigan M, Hakimé A. Percutaneous ultrasound-
guided carpal tunnel release: study upon clinical efficacy and safety. Cardiovasc 
Intervent Radiol. 2017; 40: 568–75.  
21. Rojo-Manaute JM, Capa-Grasa A, Chana-Rodríguez F, et al. Ultraminimally 
invasive ultrasound-guided carpal tunnel release: a randomized clinical trial. J 
Ultrasound Med. 2016; 35:1149–57 
22. Levine DW, Simmons BP, Koris MJ, Daltroy LH, Hohl GG, Fossel AH, et al. A 
self administered questionnaire for the assessment of severity of symptoms and 
functional status in carpal tunnel syndrome. J Bone Joint Surg. 1993; 75A:1585-
892.23. Kim JK, Jeon SH. Minimal clinically important differences in the Carpal 
Tunnel Questionnaire after carpal tunnel release. Journal of Conflict Resolution. 
2013; 38(1):75-81. DOI:10.1177/002200276100500110 
 

Date: December 1, 2020 
12.- ANNEX 1.- Validated Spanish version of the Boston Carpal Tunnel 
Syndrome Questionnair22 
The following questions refer to the patient's symptoms on a typical day (24-
hour period) during the past 2 weeks: 
 
A. How severe is your wrist or hand pain at night? 
1. I don't have pain in my wrist or hand2. I have mild pain3. I have moderate pain4. I have 
severe pain5. I have very severe pain 
 
B. How often do you wake up during a typical night with wrist or hand pain 
(during the last 2 weeks)? 
1. Never2. Once3. Two or three times4. Four to five times5. More than five times 
 
C. Do you normally have pain in your hand or wrist during the day? 
1. No2. I have mild pain3. I have moderate pain4. I have severe pain5. I have very severe pain 
 
D. How often do you have pain in your wrist or hand during the day? 
1. Never2. Once or twice3. Three to five times4. More than five times5. The pain is constant 
 
E. How long did your last bout of pain last during the day? 
1. I never have pain during the day2. 10 minutes or less3. 10-60 minutes4. More than 60 
minutes5. The pain is constant throughout the day 
 
F. Do you have numbness (loss of sensation) in your hand? 
1. No2. I have mild numbness3. I have moderate numbness4. I have severe numbness5. I have 
very bad numbness 
 
G. Do you have weakness in your hand or wrist? 

Date: December 1, 2020 
1. No2. I have mild weakness3. I have moderate weakness4. I have severe weakness5. I have 
very serious weakness 
 
 
H. Do you have a tingling sensation in your hand? 
1. No2. I have mild tingling3. I have moderate tingling4. I have severe tingling5. I have very bad 
tingling 
 
I. How serious is the numbness (loss of sensation) or tingling sensation at 
night? 
1. I don't have numbness or tingling2. I have mild numbness or tingling3. I have moderate 
numbness or tingling4. I have severe numbness or tingling5. I have very bad numbness or 
tingling 
 
J. How many times did you wake up during a typical night from numbness or 
tingling of the hand, in the last 2 weeks? 
1. Never2. Once3. Two to three times4. Four to five times5. More than five times 
 
K. Do you have difficulty grasping and using small objects such as keys or 
pens? 
1. No2. I have mild difficulty3. I have moderate difficulty4. I have serious difficulty5. I have very 
serious difficulty 
 
 
 
 
 
 
 
------------------------------------------------------------------------------------------------------------------------------- 

Date: December 1, 2020 
Please answer all answers by circling a number that you think is appropriate. 
ACTIVITY 
No 
difficulty 
Little 
Difficulty 
Moderate 
difficulty 
Severe 
difficulty 
I can't do 
anything 
because of the 
symptoms 
A.- Writing,  
1 
2 
3 
4 
5 
B.- Buttoning 
clothes,  
1 
2 
3 
4 
5 
C.- Holding a 
book while 
reading,  
1 
2 
3 
4 
5 
D.- Grab a 
phone,  
1 
2 
3 
4 
5 
E.- Open jars 
1 
2 
3 
4 
5 
,F:- Do 
household 
chores 
1 
2 
3 
4 
5 
G:- Carry 
shopping bags  
1 
2 
3 
4 
5 
H.- Bathing and 
dressing 
1 
2 
3 
4 
5