A Structured Algorithm for Decision-Making in Treatment of Carpal Tunnel Syndrome: Preliminary Report
Karpal Tünel Sendromlarinin Tedavisinde Yapılandırılmış Tedavi Algoritması: Ön Rapor
Göktekin Tenekeci1, Kazım O Unal2, Metin Akıncı2
1Department of Plastic, Reconstructive & Aesthetic Surgery, Mersin University Hospital, Mersin, Turkey
2Department of Hand and Microsurgery, Ankara Numune Training & Research Hospital, Ankara, Turkey
DOI: 10.5152/TurkJPlastSurg.2017.02229
162
www.turkjplastsurg.org
Correspondence Author / Sorumlu Yazar: Göktekin Tenekeci E-posta / E-mail: dr_tenekecig@hotmail.com
Received / Geliş Tarihi: 12.08.2016 Accepted / Kabul Tarihi: 13.02.2017 Content of this journal is licensed under a Creative Commons
Attribution-NonCommercial 4.0 International License.
Abstract
Objective: Carpal Tunnel Syndrome is a common entrapment syn- drome which lowers quality of life and is a reason for high costs for health care systems. The algorithm presented in this study may be helpful for surgeons’ decision-making for treatment of Carpal Tunnel Syndrome in terms of correct timing and treatment option.
Here, the treatment algorithm for carpal tunnel syndrome and its preliminary results are discussed.
Material and Methods: Decision-making for treatment of all Carpal Tunnel Syndrome patients enrolled in this study was per- formed according to the algorithm presented here, which is based on no thenar atrophy of patients and ability of median nerve in- nervated thenar muscles. Fifty one hands out of 88 were offered night splinting initially for three weeks while the rest thirty seven hands were operated as an emergent or urgent case without offer- ing night splinting.
Results: Quality of life of all the patients who were operated was improved except one and, awakening at night was disappeared in the postoperative period. 20 hands out of fifty one who were of- fered night splinting for three weeks were operated for carpal tun- nel release since patients felt no improvement in their complaints after three weeks of night splinting.
Conclusion: We believe that, this algorithm will help surgeons in decision-making process, determining the correct timing for sur- gery, improve patient satisfaction and provide the opportunity for explanation of the need for whichever treatment option is re- quired. The algorithmic approach we use in our cases is based on the examination of no thenar atrophy and ability of median nerve innervated thenar muscles.
Keywords: Carpal tunnel syndrome, median nerve, thenar muscle
Öz
Amaç: Karpal Tünel Sendromu hayat kalitesini düşüren ve sağlık sigorta sistemleri için yüksek maliyetlere sebep olan sık rastlanan bir tuzakanma sendromudur. Bu çalışmada sunulan algoritma, Karpal Tünel Sendromunun tedavisinde doğru zamanlama ve te- davi yönteminin belirlenmesinde cerrahlara yardımcı olabilecek bir algoritmadır. Karpal tünel sendromlarının tedavi algoritması ve ön sonuçları tartışılmaktadır.
Gereç ve Yöntemler: Bu çalışmaya dahil edilen tüm Karpal Tünel sendromlu olguların tedavisi, hastaların tenar trofisini ve median sinirin innerve ettiği tenar kasların becerisini temel alan bu algo- ritmaya göre yapılmıştır. 88 karpal tünel sendromlu elin ellibir'ine üç hafta gece atellemesi önerilmiş, geri kalan otuzyedi'si ise gece atellemesi önerilmeden acil veya acele olarak opere edilmiştir.
Bulgular: Opere edilen hastaların hayat kalitesi postoperatif dönemde biri hariç dizeldi ve gece uyanmaları geçti. Gece atel- lemesi önerilen ellibir elin 20si, üç hafta gece atellemesi sonrası şikayetlerinde gerileme olmaması sonucu opere edilerek karpal tünel serbestlemesi yapıldı.
Sonuç: Bu algoritmanın cerrahların karar verme sürecinde, doğru operasyon zamanlaması kararının alınmasına, hasta memnuniye- tinin artırılmasına ve hangi tedavi seçeneğinin açıklanabilmesine yardımcı olacağına inanmaktayız. Vakalarıımızda kullanılan bu al- goritma tenar trofi muayenesini, ve median sinirin innerve ettiği tenar kasların becerisini esas almaktadır.
Anahtar Sözcükler: Karpal Tünel Sendromu, median sinir, tenar kas
Cite this article as: Tenekeci G, Ünal KO, Akıncı M. A Structured Algorithm for Decision-Making in Treatment of Carpal Tunnel Syndrome: Preliminary Report.
Turk J Plast Surg 2017; 25(4): 162-7.
INTRODUCTION
Carpal Tunnel Syndrome (CTS) is the most frequently seen en- trapment syndrome in population.1 Patients with CTS, have lowered quality of life since the patients frequently complain of awakening at night and having difficulty during daily activ- ities and/or work. Some disorders that may accompany carpal tunnel syndrome may exacerbate symptoms. Carpal Tunnel Syndrome may sometimes be quite challenging for surgeons to decide for the correct timing of surgery and treatment modality, especially in complex cases. Here, the treatment algorithm for carpal tunnel syndrome and its preliminary results are discussed. The treatment algorithm discussed in this study, may be helpful to surgeons in decision-making for treatment of Carpal Tunnel Syndrome.
MATERIALS AND METHODS
This study is performed in accordance with Helsinki Declaration.
Eighty one patients, were diagnosed as carpal tunnel syndrome, admitted to our department through January – May 2013 were evaluated. Their chief complaints were pain, tingling and numbness of hand and awakening at night. Diagnosis of car- pal tunnel syndrome was based on patient history and physical examination in our cases. Also electrodiagnostic studies (EMG) were performed for those patients. All patients were assessed for thenar normotrophy, thenar hypotrophy and, severe thenar atrophy along with the ability of motion produced by median nerve innervated muscles of thenar region. Those items are im- portant and they build up our algorithm during decision-making process of CTS treatment. Thenar atrophy is severe devastation of thenar musculature which can be easily recognized, however thenar hypotrophy (Figure 1) can be explained as the slight dev- astation of thenar musculature over the thenar eminence. Ability of median nerve innervated thenar muscles (MNITM) is graded as normal functioning, clumsy and impaired. The patient is asked to pick up a pin from the table (Figure 2). If the patient can pick it up during the first or second attempt, MNITM are accounted as having normal ability, while if the patient is able to pick up the pin during the third or fourth attempt, MNITM are accounted as being functionally clumsy and producing clumsy fine move- ments. If patient is able to pick up the pin during the fifth at- tempt or later or unable to pick it up, it means that median nerve innervated muscles of this patient are functionally impaired and produce impaired fine movements.
In addition, the patients were questioned and evaluated for rheumatoid complaints, tennis elbow, and other additional pathologies that may accompany carpal tunnel syndrome.
Four patients who were having cervical disc hernia and three patients who were having widespread sensory-motor poly- neuropathy out of eighty one patients were not included in the study. 88 hands of 74 patients with CTS (60 unilater- al, 14 bilateral) were included in this study and all of them were treated according to the algorithm we present here in this article. For patients who were going to be operated for CTS, written informed consent was obtained. Fifty one hands were offered night splinting and rest for three weeks out of 88 hands. 20 hands out of Fifty one were operated for car-
pal tunnel release since patients felt no improvement in their complaints after three weeks of night splinting. Thirty seven hands were directly operated as an emergent or urgent case without offering night splinting (Table 1). Carpal tunnel re- lease is performed using mini incision.
14 hands of eleven patients were operated carpal for tunnel release and simultaneous tendon transfer for obtaining oppo- sition. Camitz transfer is performed for obtaining opposition in our cases but, in the absence of palmaris longus tendon or whenever it is weak, extensor indicis proprius tendon transfer was transferred for opposition.
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Figure 1. Thenar hypotrophy is seen in a patient with Carpal Tunnel Syndrome
Figure 2. Pick-up test which is used for grading and evaluating the ability of median nerve innervated thenar muscles in motion produ- ction
Two patients had thenar atrophy in one hand while thenar hy- potrophy in the other. Twelve hands of eleven patients had ten- nis elbow, eleven patients were having rheumatoid symptoms in hand and, two trigger fingers of two patients were accompa- nying to CTS. Operation of one patient, who deserved surgery for carpal tunnel release was postponed for two months since she was injected with steroid one month ago in another center.
Rheumatoid complaints were accompanying CTS in eleven pa- tients; in two, rheumatoid complaints were severe.
RESULTS
Quality of life of all the patients who were operated, was im- proved and awakening at night was disapperaed except one, during the postoperative period. Mean follow-up period was 3.9 months (2-7 months). Only one patient who had CTS symptoms for more than 20 years stated exacerbation in his complaints during the early postoperative period however his complaints gradually decreased during the follow-up period. Persistent rise in pressure of carpal tunnel leads to decreased axonal transport and intraneural blood flow, that results in fibrous scar formation of nerve.2 This may be at least partially irreversible, causing con- duction delay or complete nerve block.3 When carpal tunnel is released, reperfusion occurs in the segment of nerve where di- minished intraneural blood flow was seen. Ischemia-reperfusion injury plays a role in the symptomatology of CTS2 as in this long standing case. 20 hands out Fifty one hands who were offered night splinting for three weeks, were operated for carpal tunnel release since patients felt no improvement in their complaints after three weeks of night splinting. No thenar atrophy and abil- ity of MNITM was not exacerbated neither in cases whom CTS release was performed following night splinting which was of- fered for three weeks initially nor in other cases which were op- erated as urgent or emergent basis.
DISCUSSION
Carpal tunnel syndrome is a common disorder that causes pa- tient discomfort, functional impairment, especially in pinch-
ing and is a reason of high costs for the health care systems.
In the early twentieth century, paresthesias and numbness in the hands most prominent at night and bilateral symmetrical atrophy over the radial side of thenar eminence was named as ‘syndrome of partial thenar atrophy’.4 However, the same condition with lesser severity and without thenar atrophy was described as ‘acroparesthesia’.4 Both are now known as carpal tunnel syndrome. To the best of our knowledge, there is no re- port of an algorithm describing CTS management. The algo- rithm we present here is a candidate to fill the defficiency in the litterature for decision-making of CTS treatment. Especial- ly in complex cases, decision-making based on physical ex- amination and/or electrodiagnostic studies may be challeng- ing. Conservative treatments, surgical release of carpal tunnel and, opponensplasty in addition to carpal tunnel release are the treatment options for patients with CTS. This algorithm provides us the opportunity to determine the appropriate treatment option. The main drawback of this study is the lack of long term results. The aim of this article is to stress the im- portance of physical examination in patients with CTS.
Patients were undergone a detailed physical examination.
Other reasons that may accompany or exacerbate carpal tunnel symptoms are noted. In this study, diagnosis of CTS is based on a detailed physical examination and patient histo- ry. All the patients were undergone electrodiagnostic studies (EMG) as well. However, Graham reported that electrodiag- nostic studies did not change the probability of diagnosing CTS.5 However, nerve conduction studies and sensory tests used to quantify the severity of hand impairment and the outcome of treatments6, 7, 8 often do not correlate well with the severity of symptoms or with function.9-12 High false-neg- ative and false-positive rates serve as a reminder that atten- tion is needed when using nerve conduction study results as a measure of disease severity and treatment outcome.13 Our algorithm for treatment of Carpal Tunnel Syndrome is based on two items that correlate well with the severity of symp- toms and function; the evaluation of functionality of median nerve innervated thenar muscles (MNITM) and the degree of wasting of median nerve innervated muscles (trophy) over thenar eminence. MNITM stand for opponens pollicis, abduc- tor pollicis brevis and superficial head of flexor pollicis brevis.
The functionality of MNITM is evaluated by using pick-up test which uses tasks that resemble activities of daily life and re- quire subjects to use the median nerve innervated territory of hand.13 The degree of wasting of MNITM over thenar emi- nence is graded as normal no thenar atrophy, thenar hypotro- phy or severe thenar atrophy. The evaluation of functionality of MNITM over thenar region is graded as normal function- ing MNITM, clumsiness in MNITM and functionally impaired MNITM.
Abductor pollicis brevis (APB), a median nerve innervated muscle, is thought to be responsible from the pincer grip ac- tion.14 Pincer grip action translates the MNITM function, mainly APB function, into motion.14 Thus, we can judge and grade the MNITM function clinically. Yip et al.14 also used pick-up test to assess thenar motor deficit. But, without considering no the- nar atrophy and without grading the ability of picking-up, they
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Table I. Thenar findings and assessment of function of median nerve innervated thenar muscles (MNITM) in 37 hands which were operated either as an emergenct or an urgent case
Number
of hands No thenar Clumsy movements of MNITM 14 atrophy Impaired movements of MNITM 3
Thenar Normal movements of MNITM 2
hypotrophy Clumsy movements of MNITM 3 Impaired movements of MNITM 2 Thenar atrophy Normal movements of MNITM 1 Clumsy movements of MNITM 1 Impaired movements of MNITM 11
Total 37
MNITM: median nerve innervated thenar muscles
performed opponensplasty for all cases who failed to pick-up a coin. However we think that CTS release in combination with opponensplasty should be indicated in cases which no thenar atrophy and functional ability of MNITM are graded since, im- paired motion of MNITM may sometimes be reversible espe- cially in less severe cases. Eight cases Yip et al.14 have presented in their study have first used conservative treatment. But when conservative treatment failed to improve patients’s condition, they decided to make opponensplasty in addition to CTS re- lease. However we believe that, if a patient needs opponens- plasty in addition to carpal tunnel release, we have to release carpal tunel soon before MNITM are further damaged. Degree of muscle wasting is one of the determinants for regaining functional abilities of MNITM. Camitz transfer is indicated in thenar atrophy and in loss of palmar abduction in patients with severe long standing carpal tunnel syndrome.15
If patients with CTS do not exhibit thenar atrophy/hypotrophy and clumsiness/impairment in MNITM while they have rheu- matoid complaints, such as morning stiffness in hands which lasts more than an hour, and a warm environment helps re- lieving stiffness, night splinting for three weeks is suggest- ed. If tennis elbow is accompanying CTS and patient has no thenar hypotrophy/atrophy and no clumsiness/impairment of MNITM, night splinting and resting for three weeks is sug- gested. This may be helpful in relieving symptoms. If patient has cervical disc herniation and CTS symptoms at the same time, it is difficult to judge how much of those symptoms are caused by cervical disc herniation, and how much originates from median nerve entrapment in carpal tunnel. That’s why in such cases, patients are first consulted to Neurosurgery and are followed-up regularly. If patient complaints don’t subside inspite of all efforts been taken, CTS release may be encoun- tered after discussing the case in details with the patient.
All patients who are diagnosed with CTS, must not undergo release procedure since non-operative treatments can work in selected cases. Most guidelines suggest a course of non- operative treatment in patients diagnosed with carpal tunnel syndrome.16 Significant short term benefits can be achieved with conservative treatment such as splinting, oral steroids, ultrasound, yoga and carpal bone mobilisation, however duration of effectiveness of such conservative treatments remain unclear.17 Spontaneous improvement in symptoms, with reported rates of thirty three to fourty percent experi- encing some improvement was reported, depending on elec- trodiagnostic study severity.18-21 However, no thenar atrophy and movements of MNITM must be well evaluated, since find- ings in related to physical examination eases decision-making for conservative or operative treatment, the timing of CTS re- lease and the possible need for tendon transfer procedure in order to create opposition.
Since CTS is a progressive disorder timing and decision-mak- ing of CTS release is important. As severity of CTS increases, MNITM will become weakened, devastated, and therefore thenar hypotrophy or thenar atrophy may develop in time.
Similarly, normal ability and function of MNITM may become
‘clumsy’ or ‘impaired’ over time as the median nerve becomes
more severely entrapped. Median nerve segment under trans- verse carpal ligament is under progressive tension and this may cause progressive dysfunction of median nerve distal to the carpal tunnel. This means that median nerve innervated muscles in thenar region, namely opponens pollisis, abduc- tor pollicis brevis (mostly whole muscle body is innervated by median nerve) and flexor pollicis brevis (partially innervated by median nerve), may dysfunction thereby causing ‘clumsi- ness’ / ‘impairment’ especially during ‘pinching’. Therefore we evaluated the ability of MNITM by pick-up test. Also thenar muscles may diminish in size causing thenar hypotrophy or thenar atrophy. Camitz transfer is indicated in thenar atro- phy and in loss of palmar abduction in patients with severe long standing carpal tunnel syndrome.15 Therefore it is well accepted that, in patients with loss of palmar abduction and thenar atrophy, functional loss is less likely to be reversible.
Ability to reverse dysfunction of MNITM following CTS release is dependent on the trophy of thenar muscles. This is the rea- son why we perform CTS release as urgency or emergency, in cases with clumsy or impaired fine movements and normal no thenar atrophy or thenar hypotrophy. In such cases we believe that the ability of MNITM is more likely to return nor-
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Figure 3. The algorithm used in patients who have Carpal Tunnel Syn- drome with normal no thenar atrophy
Figure 4. The algorithm used in patients who have Carpal Tunnel Syn- drome with thenar hypotrophy
mal or near normal. As a result, patients with thenar atrophy without signs of ulnar nerve compensation and patients with impaired fine movements of MNITM accompanying thenar hypotrophy are indicated for Camitz transfer. Those are the ideas behind the algorithm we use.
A Carpal Tunnel Syndrome patient, who has normal no thenar atrophy and has normally functioning MNITM, still has time and chance to benefit from non-operative treatment such as night splinting for three weeks and resting (Figure 3). If the pa- tient complaints do not disappear or subside during this time, CTS release is suggested. If a patient with CTS has clumsiness/
impairment in MNITM function and/or thenar hypotrophy CTS release operation must be performed either as an urgen- cy (performed within three weeks) or as an emergency (per- formed within 1 week) operation (Figure 3, 4). If operation is postponed in such cases MNITM abilities may exacerbate and become clumsy or impaired. Also no thenar atrophy may be devastated and MNITM may become hypotrophic or atrophic.
Normal motion is seldomly produced by MNITM, in cases with thenar atrophy. In patients with thenar atrophy, if no clumsiness or impairment is seen with MNITM, only CTS release procedure is performed. Compensation or cross innervation of MNITM through ulnar nerve may cause normal ability of MNITM, in- spite of the presence of thenar atrophy. Wee has reported that absolute amplitude of ulnar compound muscle action poten- tials recorded at thenar area does not seem to be influenced significantly by the degree of thenar atrophy from median nerve pathologhy.22 However, there have been reports about significant preservation of function in CTS patients which was explained with the presence of Riche-Cannieu anastomosis.23 CTS release and Camitz transfer procedures are planned as an emergency procedure (performed in a week time) in case if patient has severe thenar atrophy and clumsiness in MNITM.
This condition is accepted as an emergency since in addition to an atrophic thenar musculature, movements of MNITM may be exacerbating. CTS release and Camitz transfer is performed if patient has severe thenar atrophy and impairment in fine movements MNITM, but such cases are not encountered as an emergency or urgency. (Figure 5)
CONCLUSION
Carpal Tunnel Syndrome patients may admit to hospitals with various clinical findings and accompanying disorders in single hand or both hands, which may confuse surgeons in deci- sion-making process. To the best of our knowledge, there is no study reporting an algorithm for CTS management. This study is a preliminary report in treatment of carpal tunnel syndrome.
We believe that, this algorithm is going to help surgeons in de- cision-making process, determining the correct timing for sur- gery and improve patient satisfaction. Also, prioritazing which side to be operated first, in case if both sides are effected can be decided. Accompanying disorders that may exacerbate patient complaints must be discussed with the patients. This algorithm is inspired through the progressive nature of CTS if left untreat- ed. History and physical examination are very important issues that guide us during our decision-making for treatment of CTS.
Ability of MNITM and assessment of no thenar atrophy are the two main determinants of the algorithm we use.
Ethics Committee Approval: Authors declared that the research was conducted according to the principles of the World Medical Associ- ation Declaration of Helsinki “Ethical Principles for Medical Research Involving Human Subjects” (amended in October 2013).
Informed Consent: Written informed consent was obtained from the patients for the publication of this study.
Peer-review: Externally peer-reviewed.
Author contributions: Concept - G.T., M.A.; Design - G.T., M.A.; Super- vision - G.T., M.A., K.O.U.; Resource - G.T., M.A., K.O.U.; Materials - X.X., X.X., X.X.; Data Collection and/or Processing - G.T., M.A., K.O.U.; Anal- ysis and/or Interpretation - G.T., M.A.; Literature Search - G.T.; Writing Manuscript - G.T.; Critical Reviews - G.T., K.O.U.
Conflict of Interest: No conflict of interest was declared by the authors.
Financial Disclosure: The authors declared that this study has re- ceived no financial support.
Etik Komite Onayı: Yazarlar çalışmanın World Medical Association Declaration of Helsinki “Ethical Principles for Medical Research Involv- ing Human Subjects”, (Ekim 2013’te gözden geçirilmiş) prensiplerine uygun olarak yapıldığını beyan etmişlerdir.
Hasta Onamı: Yazılı hasta onamı bu çalışmaya katılan hastalardan alınmıştır.
Hakem Değerlendirmesi: Dış bağımsız.
Yazar Katkıları: Fikir - G.T., M.A.; Tasarım - G.T., M.A.; Denetleme - G.T., M.A., K.O.U.; Kaynaklar - G.T., M.A., K.O.U.; Malzemeler - x.x.; Veri To- planması ve/veya işlemesi - G.T., M.A., K.O.U.; Analiz ve/veya Yorum - G.T., M.A.; Literatür taraması - G.T.; Yazıyı Yazan - G.T.; Eleştirel İnce- leme - G.T., K.O.U.
Çıkar Çatışması: Yazarlar çıkar çatışması bildirmemişlerdir.
Finansal Destek: Yazarlar bu çalışma için finansal destek almadıklarını beyan etmişlerdir.
166
Figure 5. The algorithm used in patients who have Carpal Tunnel Sy- ndrome with thenar atrophy
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