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Síndrome do túnel radial

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Radial tunnel syndrome — causes forearm pain, weakness straightening fingers, and is distinct from tennis elbow.

Updated Oct 2026
Ilustração de uma pessoa segurando a parte externa superior do antebraço, sentindo dor.
A síndrome do túnel radial provoca uma dor incômoda na parte externa superior do antebraço, logo abaixo do cotovelo. Kieran Hirpara 4.0

Esta página foi traduzida automaticamente e ainda não foi verificada por um médico. A versão em inglês é a versão oficial.

O que você está sentindo

O principal sintoma é dor na parte externa do antebraço, perto do cotovelo. Ela geralmente é mais forte num ponto sensível alguns centímetros abaixo da protuberância óssea na parte externa do cotovelo. Pressionar esse ponto muitas vezes dói. A dor pode se espalhar pela parte de trás do antebraço em direção ao punho.

Certos movimentos a pioram. Girar a palma da mão para cima contra uma resistência, ou esticar o dedo médio contra uma resistência, pode provocar a dor. O mesmo acontece com atividades que colocam carga contínua no antebraço. Muitas pessoas notam que a dor piora depois do trabalho ou do esporte, e não em repouso.

Esta condição afeta um nervo que comanda músculos, e não a pele. Isso significa que é improvável que você tenha dormência ou formigamento, e o próprio nervo geralmente funciona normalmente. O problema é a dor, e não fraqueza nem perda de sensibilidade.

No dia a dia, a dor tende a aparecer em tarefas que exigem segurar e torcer. Levantar uma chaleira, girar uma maçaneta, usar uma chave de fenda ou torcer um pano podem doer. Como o ponto sensível fica perto da parte externa do cotovelo, esta condição muitas vezes é confundida com o cotovelo do tenista, e as duas podem ocorrer juntas.

Não existe um único exame que confirme esta condição. O seu cirurgião chega ao diagnóstico a partir da sua história e de um exame físico, procurando aquele ponto sensível específico e o padrão da sua dor.

Fique atento a estes sinais. Procure o seu médico de família ou peça uma avaliação com especialista se os seus sintomas não estiverem melhorando, estiverem piorando ao longo de semanas, acordarem você à noite ou impedirem você de trabalhar ou de usar o braço. Vá ao pronto-socorro no mesmo dia se o braço ficar quente, vermelho, inchado e dolorido, especialmente se houver febre, ou se a mão ficar pálida, fria, branca ou azulada. Se não conseguir contato com a clínica fora do horário de atendimento ou no fim de semana, vá ao pronto-socorro mais próximo.

O que está realmente acontecendo

A dor vem de um nervo, e não da própria articulação do cotovelo. Um nervo é um cabo que transmite sinais entre o cérebro e os músculos. Um ramo do nervo radial desce pela parte externa do antebraço, passando pelo cotovelo, para comandar os músculos que esticam o punho e os dedos.

Ao longo desse trecho, várias estruturas diferentes ficam perto do nervo. A borda de um músculo, uma faixa fibrosa ou um pequeno grupo de vasos sanguíneos que cruzam por ali podem, cada um, pressioná-lo. Não se trata de uma única passagem estreita. É mais como uma trilha com vários possíveis pontos de estrangulamento ao longo do caminho, e qualquer um deles pode apertar o cabo que corre ao lado.

Quando uma dessas estruturas pressiona o nervo, ele fica irritado e dolorido. É por isso que a dor fica num ponto sensível abaixo da protuberância óssea na parte externa do cotovelo, e é por isso que girar a palma da mão para cima ou esticar o dedo médio contra uma resistência a piora. Esses movimentos tracionam os músculos que esse nervo comanda, e o nervo irritado reclama.

O nervo continua funcionando, por isso os seus músculos continuam trabalhando e você não sente dormência nem formigamento. O problema é irritação e dor, e não perda de sinal. Como o ponto dolorido fica muito perto da parte externa do cotovelo, a dor é facilmente confundida com o cotovelo do tenista, que afeta um tendão na mesma região. As duas condições podem até acontecer juntas.

O que podemos fazer a respeito

O Dr. Kieran Hirpara, cirurgião de membros superiores no Mater Private Hospital Rockhampton, começa com as opções menos invasivas adequadas ao seu caso. Em geral, os pacientes são encaminhados à nossa clínica pelo médico de família; caso um fisioterapeuta tenha sugerido que você nos procure, ainda assim será necessário um encaminhamento do seu médico de família para que você tenha direito ao reembolso do Medicare. Na clínica, colhemos o histórico clínico, examinamos o seu braço e solicitamos exames de imagem, se forem ajudar. Para esta condição, normalmente tentamos primeiro o tratamento não cirúrgico e consideramos a cirurgia quando ele não trouxe melhora suficiente.

O primeiro passo é mudar a forma como você usa o braço. Reduzir as tarefas de segurar e torcer que desencadeiam a dor dá ao nervo irritado a chance de se acalmar. A terapia da mão tem como objetivo acalmar a dor e reconstruir a sua tolerância à carga no antebraço, para que o trabalho e as tarefas do dia a dia voltem a ser confortáveis. Pedimos que você dê a essas medidas uma tentativa adequada antes de pensar em qualquer outra coisa.

Analgésicos e anti-inflamatórios podem ajudar você a atravessar uma crise de dor. Eles aliviam o incômodo enquanto as outras medidas fazem efeito. Eles não resolvem a pressão sobre o próprio nervo.

Se o tratamento não cirúrgico não trouxe melhora suficiente, a cirurgia é uma opção. A operação se chama liberação do túnel radial. Ela funciona soltando o nervo em cada um dos pontos onde uma estrutura vizinha o está pressionando. Antes de recomendá-la, verificamos com cuidado onde o nervo está sendo comprimido, para que a operação atinja o ponto certo e mexa o mínimo possível nos tecidos ao redor. Como o diagnóstico depende da sua história e do exame físico, e não de um exame claro, tratamos a decisão de operar como uma decisão compartilhada, tomada em conjunto depois que você entender o que a cirurgia pode e não pode resolver.

O que esperar

Na maioria das pessoas, esta condição não danifica o nervo. O nervo continua funcionando, por isso os seus músculos continuam trabalhando e você não perde a sensibilidade. O problema é a dor, e a dor de um nervo irritado pode levar muito tempo para se acalmar. Ela raramente desaparece da noite para o dia, e muitas vezes piora com tarefas de segurar e torcer antes de diminuir.

A verdade é que esta condição é difícil de prever. Algumas pessoas melhoram com repouso, mudanças nas atividades e terapia da mão. Outras continuam com dor apesar de um bom tratamento não cirúrgico. Não existe um exame confiável para confirmar o diagnóstico, o que torna mais difícil dizer de antemão em qual grupo você vai ficar. O que podemos dizer é que a dor tende a ir e vir conforme a carga que você coloca no antebraço, em vez de aumentar de forma constante.

Se o tratamento não cirúrgico funcionar, a dor diminui gradualmente ao longo de semanas a meses, à medida que o nervo fica menos irritado. É de esperar que tarefas do dia a dia, como levantar uma chaleira ou girar uma maçaneta, fiquem menos dolorosas primeiro, antes que trabalhos mais pesados voltem a parecer normais. Se a cirurgia for feita depois que o tratamento não cirúrgico não ajudou o suficiente, a recuperação também é gradual, e não imediata, e algumas pessoas ainda têm alguma dor depois.

Se a condição não for tratada, ela pode melhorar sozinha, mas também pode persistir ou continuar piorando sempre que você voltar às tarefas que a agravam. Não há como saber de antemão o que vai acontecer. O que costuma fazer diferença é dar ao tratamento uma tentativa adequada e não forçar apesar de uma dor que não está melhorando.

Se os seus sintomas não estiverem melhorando, estiverem piorando ao longo de semanas, acordarem você à noite ou impedirem você de trabalhar ou de usar o braço, procure o seu médico de família ou peça uma avaliação com especialista. Vá ao pronto-socorro no mesmo dia se o braço ficar quente, vermelho, inchado e dolorido, especialmente se houver febre, ou se a mão ficar pálida, fria, branca ou azulada. Se não conseguir contato com a clínica fora do horário de atendimento ou no fim de semana, vá ao pronto-socorro mais próximo.

Quando procurar ajuda médica

Os sinais de alerta desta condição dizem respeito a uma dor que não melhora, e não a perigo. Procure o seu médico de família ou peça uma avaliação com especialista se a dor no antebraço não tiver melhorado após uma tentativa adequada de repouso e mudanças nas atividades, ou se ela continuar impedindo você de trabalhar ou de usar o braço. Peça a avaliação mais cedo, e não mais tarde, se o ponto sensível abaixo da parte externa do cotovelo for uma característica marcante, ou se girar a palma da mão para cima ou esticar o dedo médio contra uma resistência sempre provocar a dor. Esses padrões apontam para esta condição, e não para o cotovelo do tenista, e vale a pena esclarecê-los adequadamente.

Esta condição geralmente não danifica o nervo, por isso uma fraqueza repentina do punho ou dos dedos não faz parte do quadro típico. Se você notar uma fraqueza nova para esticar o punho, os dedos ou o polegar, peça uma avaliação com especialista prontamente, em vez de esperar, porque esse padrão sugere um problema nervoso diferente, que é avaliado no seu próprio prazo.

Vá a um pronto-socorro no mesmo dia se o braço ficar quente, vermelho, inchado e dolorido, especialmente se houver febre, ou se a mão ficar pálida, fria, branca ou azulada. Se não conseguir contato com a clínica fora do horário de atendimento ou no fim de semana, vá ao pronto-socorro mais próximo.

Em maior profundidade

Advanced reading: the deeper science (optional)

Esta seção vai além do que você precisa saber para tomar decisões sobre seu próprio tratamento. A síndrome do túnel radial merece ser lida com atenção, por um motivo desconfortável: trata-se da condição nesta região com a base de evidências mais fraca; não existe nenhum exame que a confirme, e informar claramente sobre essa incerteza deve fazer parte de qualquer decisão cirúrgica.

Não existe exame confirmatório

A maioria das compressões nervosas pode ser comprovada. A síndrome do túnel do carpo causa lentidão na condução nervosa no nível do punho; a síndrome do túnel cubital, no nível do cotovelo. Já na síndrome do túnel radial, isso geralmente não ocorre: o ramo nervoso envolvido inerva músculos, não a pele; portanto, não há dormência que possa ser mapeada, e os estudos de condução nervosa frequentemente apresentam resultados normais.

Assim, o diagnóstico baseia-se no padrão de dor, na presença de sensibilidade à palpação a poucos centímetros distalmente ao epicôndilo lateral (e não exatamente sobre ele), e na resposta ao bloqueio anestésico local. Cada um desses critérios é sugestivo, porém nenhum é definitivo. Revisões recentes descrevem controvérsias contínuas tanto quanto ao diagnóstico quanto aos resultados terapêuticos [1].

A consequência prática disso é uma alta taxa de confusão com a epicondilite lateral, condição que se localiza nas proximidades e pode coexistir com a síndrome do túnel radial. A persistência dos sintomas da “epicondilite lateral” mesmo após tratamento adequado é uma das situações mais comuns em que a síndrome do túnel radial acaba sendo considerada.

As evidências para o tratamento são realmente escassas

Uma revisão sistemática de intervenções constatou uma tendência de que a descompressão cirúrgica possa ser eficaz; o achado mais notável foi que a eficácia dos tratamentos conservadores é desconhecida, pois para a maioria deles não há nenhum estudo disponível [2].

Essa não é a formulação habitual do tipo “as evidências são limitadas”. Para a maioria dos tratamentos não cirúrgicos indicados para essa condição, simplesmente não foram realizados estudos. As revisões atuais ainda colocam o manejo não cirúrgico em primeiro lugar, considerando a descompressão uma opção viável para casos refratários [1]; essa ordem reflete uma cautela razoável, e não uma superioridade comprovada.

O que isso significa para a tomada de decisão

Duas consequências surgem, e elas apontam em direções opostas.

Contra a cirurgia precoce: o diagnóstico não pode ser confirmado, portanto a operação pode acabar descomprimindo um nervo que não é a causa do problema. Quando a descompressão falha, muitas vezes é impossível determinar se a operação foi inadequada ou se o diagnóstico estava errado.

Para considerar a cirurgia no paciente certo: também não há base científica que apoie as outras alternativas; assim, a espera não é a opção respaldada por evidências como as pessoas supõem. É simplesmente a opção de menor risco.

A postura razoável é reconhecer que, aqui, um diagnóstico seguro é mais importante do que em qualquer outro contexto abordado neste site: um histórico clínico consistente, exame físico que localize a lesão no túnel radial em vez do epicôndilo, exames de imagem que excluam a presença de lesões ocupantes de espaço e, idealmente, uma resposta convincente a um bloqueio diagnóstico, antes de se tomar uma medida irreversível.

Um problema relacionado, porém distinto

A paralisia do nervo interósseo posterior, caracterizada por fraqueza na extensão dos dedos e do polegar, e não por dor, é uma condição distinta, cujo tratamento é mais bem definido. Quando os exames de imagem não revelam nenhuma lesão compressiva, deve-se optar inicialmente pelo tratamento conservador; a cirurgia fica reservada para casos em que há lesões compressivas comprovadas ou quando o tratamento conservador falha [3]. Na ausência de lesões que ocupem espaço, recomenda-se tentar o tratamento não cirúrgico; a exploração cirúrgica é indicada caso não haja sinais de recuperação muscular após 6 semanas de observação ou se a fraqueza muscular for progressiva [4].

Esses são limites concretos, e sua existência ilustra claramente a diferença entre os casos: quando o nervo deixa de funcionar visivelmente, a literatura médica consegue indicar o que fazer e quando. Quando há apenas dor, isso não é possível.

Referências

[1] Wolf JM, Patel R, Ghosh K. Síndrome do túnel radial: revisão e melhores evidências. J Am Acad Orthop Surg. 2023;31(15):813-9. https://doi.org/10.5435/JAAOS-D-23-00314

[2] Huisstede B, Miedema HS, van Opstal T, de Ronde MT, Verhaar JA, Koes BW. Intervenções para o tratamento da síndrome do túnel radial: uma revisão sistemática de estudos observacionais. J Hand Surg Am. 2008;33(1):72.e1-72.e10. https://doi.org/10.1016/j.jhsa.2007.10.001

[3] McGraw I. Paralisia espontânea isolada do nervo interósseo posterior: revisão da etiologia e manejo. J Hand Surg Eur Vol. 2018;44(3):310-6. https://doi.org/10.1177/1753193418813788

[4] Sigamoney KV, Rashid A, Ng CY. Manejo da paralisia não traumática do nervo interósseo posterior. J Hand Surg Am. 2017;42(10):826-30. https://doi.org/10.1016/j.jhsa.2017.07.026

Reviewed by Dr Kieran Hirpara · 7 August 2026.

Talk to your treating clinician for advice specific to you.

For an appointment with the CQ Hand + Upper Limb team, ask your GP about a referral or visit www.cqupperlimb.com.

Evidence & references

This is the clinical evidence summary written for health professionals. It is technical, and it lists the research this page was built from. You do not need to read it to understand your treatment or to make a decision about it.

Overview

  • Radial tunnel syndrome is relatively uncommon but is an important cause of lateral forearm pain [1].
  • Clinical examination is a crucial part of the diagnosis of radial tunnel syndrome [1].
  • The duration of symptoms averaged 2.3 years before a definitive diagnosis of radial tunnel syndrome was made [2].
  • The diagnosis of radial tunnel syndrome remains clinical [5].
  • Adherence to a defined protocol is useful in diagnosing radial tunnel syndrome [5].
  • The issue surrounding radial tunnel syndrome traditionally has been properly identifying it clinically [7].
  • Compression of the radial nerve at the elbow is of moderate frequency compared to the ulnar tunnel syndrome [9].
  • A case of bilateral radial tunnel syndrome with signs discordant with traditionally used clinical diagnostic tests was successfully relieved with surgical decompression [6].
  • The Rule-of-Nine test effectively specifies the site of tenderness for the diagnosis of radial tunnel syndrome [11].

Anatomy & Pathophysiology

Clinical Presentation & Diagnostic Challenges

  • Radial tunnel syndrome is a relatively uncommon but important cause of lateral forearm pain [1].
  • Clinical examination is a crucial component of the diagnosis for radial tunnel syndrome [1].
  • The average duration of symptoms before a definitive diagnosis of radial tunnel syndrome was 2.3 years [2].
  • Prominent focal tenderness in the area of the radial tunnel is a principal diagnostic criterion for radial tunnel syndrome [20].
  • In radial tunnel syndrome, symptoms do not occur in the distribution of the purportedly affected nerve, which distinguishes focal tenderness from a positive Phalen's test in carpal tunnel syndrome [20].
  • Skeptics note that radial tunnel syndrome presents with normal neurologic function and no confirmatory electrodiagnostic evidence of nerve dysfunction, contrasting with other well-described entrapment neuropathies [20].

Etiology & Pathophysiology

  • There is dispute over the etiology of radial tunnel syndrome, with some skeptics questioning its status as a viable entrapment neuropathy [20].
  • The posterior interosseous nerve carries unmyelinated (group IV) afferent fibers from the wrist capsule and small myelinated (group IIA) afferent fibers from muscles along its distribution [20].
  • Unmyelinated group IV fibers are associated with nociception and pain [20].
  • The current best evidence for the conservative management of radial tunnel syndrome consists primarily of expert opinion and inferences from studies on other nerve compressions [3].

Relevant Elbow Anatomy

  • The elbow is a trocho-ginglymoid joint consisting of medial and lateral articulations that afford bony stability [63].
  • The ulnohumeral joint is formed by the articulation of the trochlea with the ulna within the greater sigmoid notch [63].
  • The radiocapitellar joint is formed by the articulation of the capitellum and radial head [63].
  • The radius is held in close approximation to the ulna at the proximal radioulnar joint by the annular ligament [63].
  • The lateral epicondyle is the origin of the lateral extensor musculature [63].
  • The radial nerve enters the interval between the brachialis and brachioradialis muscles in the proximal angle of the lateral approach to the elbow [66].
  • The deep branch of the radial nerve enters the supinator muscle [66].
  • The posterior interosseous nerve is located just superficial to the anterior joint capsule at the level of the radiocapitellar joint [75].
  • At the level of the radial neck, the posterior interosseous nerve may come in direct contact with the joint capsule [75].
  • Supination increases the linear distance between the posterior interosseous nerve and the radial head [107].

Classification

  • Radial tunnel syndrome (RTS) and posterior interosseous nerve (PIN) compression are distinct entities with different clinical presentations but share identical potential sites of nerve interference [29].
  • The author of [29] proposes unifying RTS and PIN compression as mild and severe forms of one disease to simplify nomenclature [29].
  • The authors of [52] recommend viewing radial tunnel syndrome and posterior interosseous nerve syndrome as a single condition presenting along a spectrum of nerve entrapment [52].
  • Radial tunnel syndrome is a pain syndrome caused by compression of the posterior interosseous nerve at the proximal forearm [22].
  • The diagnosis of radial tunnel syndrome remains clinical, and adherence to a defined protocol is useful in diagnosing this condition [5].
  • A differential latency of ≥0.30 ms was considered indicative of radial tunnel syndrome [16].
  • Radial tunnel syndrome is an illness construct based on a speculative pathophysiology with no verifiable pathophysiology or accepted reference standard for diagnosis [14].
  • Skeptics note that the signs and symptoms of RTS contrast from other well-described entrapment neuropathies in that there is prominent focal tenderness, normal neurologic function, and no confirmatory electrodiagnostic evidence of nerve dysfunction [20].
  • Prominent focal tenderness in the area of the radial tunnel remains one of the principal diagnostic criteria for RTS [20].
  • Focal tenderness at the radial tunnel in RTS differs from a positive Phalen's test in carpal tunnel syndrome in that the symptoms do not occur in the distribution of the purportedly affected nerve [20].
  • There has been no randomized controlled trial that compares surgical with nonsurgical treatment or with a placebo for RTS [20].
  • Skeptics of RTS point to the great variability of surgical results reported in the literature as one of the characteristics of placebo surgery [20].

Clinical Presentation

  • Radial tunnel syndrome is a relatively uncommon cause of lateral forearm pain [1].
  • Radial tunnel syndrome and posterior interosseous nerve compression are distinct entities with different clinical presentations [29].
  • The author proposes unifying radial tunnel syndrome and posterior interosseous nerve compression as mild and severe forms of one disease to simplify nomenclature [29].
  • The authors recommend viewing radial tunnel syndrome and posterior interosseous nerve syndrome as a single condition presenting along a spectrum of nerve entrapment [52].
  • Prominent focal tenderness in the area of the radial tunnel is one of the principal diagnostic criteria for radial tunnel syndrome [20].
  • In radial tunnel syndrome, symptoms do not occur in the distribution of the purportedly affected nerve, which differs from a positive Phalen's test in carpal tunnel syndrome [20].
  • A diagnosis of radial tunnel syndrome should be considered in patients with forearm and wrist pain that has not responded to more conventional treatment [13].
  • The diagnosis of radial tunnel syndrome remains clinical, and adherence to a defined protocol is useful in diagnosing the condition [5].
  • The issue surrounding radial tunnel syndrome has traditionally been properly identifying it clinically [7].
  • A case of bilateral radial tunnel syndrome presented with signs discordant with traditionally used clinical diagnostic tests [6].
  • Muscle denervation edema or atrophy along the distribution of the posterior interosseous nerve is the most common MR finding in radial tunnel syndrome [32].
  • A symptomatic double-level entrapment of the posterior interosseous branch of the radial nerve has been described [51].
  • Compression of the radial nerve at the elbow is of moderate frequency compared to ulnar tunnel syndrome [9].
  • The annual incidence rate of posterior interosseous nerve entrapment is estimated to be 0.03% [88].
  • The most frequent location of radial nerve entrapment is around the elbow, specifically involving the posterior interosseous nerve branch [88].
  • The radial tunnel spans 5 cm, extending from the humero-radial joint and running distally between the deep and superficial heads of the supinator [88].
  • The radial tunnel is bounded laterally by extensor carpi radialis longus and extensor carpi radialis brevis muscles and medially by biceps tendon and the brachialis [88].
  • The roof of the radial tunnel is formed by brachioradialis [88].
  • The floor of the radial tunnel is the elbow-joint capsule [88].
  • Potential sites of entrapment in the radial tunnel include capsular tissue of the radiocapitellar joint, hypertrophic crossing branches of leash of Henry, the leading proximal tendinous and medial edge of ECRB, the arcade of Frohse, and the distal border of the supinator between its two heads [88].
  • The arcade of Frohse is noted to be the most common site of entrapment in the radial tunnel [88].
  • Clinical criteria for radial tunnel syndrome include activity-related pain, maximal tenderness 3–5 cm distal to the lateral epicondyle, pain exacerbation with forearm supination, radiation to the dorsoradial aspect of the forearm, and a positive Lister test [81].
  • A clinical diagnosis of radial tunnel syndrome requires 4 of 5 diagnostic signs and symptoms, with one being maximal tenderness 3–5 cm distal to the lateral epicondyle [81].
  • Physical examination for radial tunnel syndrome includes wrist flexion and forearm pronation, the Rule of Nines test, and assessment of weakness and pain with resisted long finger extension [86].
  • The history for radial tunnel syndrome includes extensor musculature "forearm aching" [86].

Investigations

Clinical Diagnosis

  • A diagnosis of radial tunnel syndrome should always be born in mind when dealing with patients with forearm and wrist pain that has not responded to more conventional treatment [13].
  • It is important to understand the anatomic course and distribution of the radial nerve in order to make an accurate diagnosis [24].

Electrodiagnostic Studies

Imaging

  • Neuroimaging should be considered as a complementary diagnostic method in posterior interosseous neuropathy [132].
  • Dynamic ultrasonographic assessment of changes in the AP diameter and CSA is an effective diagnostic tool for identifying radial tunnel syndrome [121].
  • Ultrasonography, computed tomography, and magnetic resonance imaging revealed the location of the ganglion in every patient with radial nerve palsy caused by a ganglion [124].
  • The authors acknowledge that their study does not establish diagnostic accuracy or a reference standard for radial tunnel syndrome [49].

Treatment

Non-Operative Management

  • Current best evidence for the conservative management of radial tunnel syndrome consists primarily of expert opinion and inferences taken from studies on other nerve compressions and related syndromes [3].
  • The effectiveness of conservative treatments for radial tunnel syndrome is unknown because, for most treatments, no studies are available [48].
  • Prospective evaluation of a single corticosteroid injection demonstrated improvement in standardized outcomes measures of pain and function at one year in 75% of patients presenting with symptoms of radial tunnel syndrome [8].
  • Nonsurgical management is first-line for radial tunnel syndrome [4].
  • The two most common nerve entrapment disorders about the elbow, including radial tunnel, should be initially managed conservatively before considering surgical intervention [80].

Operative Management

  • Surgical decompression remains a viable option for refractory cases of radial tunnel syndrome despite ongoing controversy regarding diagnosis and outcomes [4].
  • There is a tendency that surgical decompression of the radial tunnel might be effective in patients with radial tunnel syndrome [48].
  • The authors advocate for surgery in high radial nerve entrapment neuropathy cases resistant to conservative treatment, emphasizing the importance of dissecting the entire length of the fibrous tunnel [17].
  • This study indicates that pain in patients with radial tunnel syndrome may be treated successfully by surgical decompression of the superficial branch of the radial nerve [104].
  • The results of radial tunnel release have been sufficiently good thus far as to warrant some attention, with an overall significant improvement in 99 of 108 cases (91.7%) when combined with other series [19].
  • Nineteen patients (20 extremities) felt satisfied and helped and believed they gained improved function because of surgical decompression of the radial tunnel [27].
  • The authors believe that a high rate of morbidity is associated with both the disease and its treatment, suggesting that great caution has to be taken before performing radial tunnel release [26].
  • The authors suggest that great caution be taken before performing radial tunnel release and strict adherence to the indications noted during the preoperative examination [50].

Evidence Limitations and Controversy

  • There has been no randomized controlled trial that compares surgical with nonsurgical treatment or with a placebo for radial tunnel syndrome [20].
  • Skeptics of radial tunnel syndrome point to the great variability of surgical results reported in the literature as one of the characteristics of placebo surgery [20].
  • Although radial tunnel syndrome is classically described as a nerve compression and entrapment syndrome, there is dispute over its etiology [20].

Complications

  • A high rate of morbidity is associated with both radial tunnel syndrome and its treatment [26].
  • In a case of congenital compression of the radial nerve, the patient was followed for an additional 3 months without clinical improvement in radial nerve function [12].
  • Nerve injury is an uncommon though troublesome complication of fractures or dislocations of the elbow [39].

Recovery

  • A patient with congenital compression of the radial nerve was followed for an additional 3 months without clinical improvement in radial nerve function [12].
  • In a patient with posterior interosseous-nerve syndrome secondary to rheumatoid synovitis where the duration of entrapment was more than two years, a tendon transfer was used as treatment [139].
  • Isolated posterior interosseous nerve neurectomy has shown excellent clinical outcomes, with few patients experiencing recurrent pain at long-term follow-up [123].

Key Evidence

  • [L5] Radial tunnel syndrome is relatively uncommon but is an important cause of lateral forearm pain, with clinical examination being a crucial part of the diagnosis. [1] (10.1197/j.jht.2006.02.005)
  • [L4] The duration of symptoms averaged 2.3 years before a definitive diagnosis of radial tunnel syndrome was made. [2] (10.1016/s0363-5023(83)80201-9)
  • [L5] Current best evidence for the conservative management of radial tunnel syndrome (RTS) consists primarily of expert opinion and inferences taken from studies on other nerve compressions and related syndromes. [3] (10.1197/j.jht.2006.02.020)
  • [L4] The article reviews the anatomy, diagnosis, and treatment of radial tunnel syndrome, noting that while nonsurgical management is first-line, surgical decompression remains a viable option for refractory cases despite ongoing controversy regarding diagnosis and outcomes. [4] (10.5435/jaaos-d-23-00314)
  • [L4] The diagnosis of radial tunnel syndrome remains clinical, and adherence to a defined protocol is useful in diagnosing this condition. [5] (10.1016/s0266-7681(98)80015-6)
  • [L5] A case of bilateral radial tunnel syndrome with signs discordant with traditionally used clinical diagnostic tests was successfully relieved with surgical decompression. [6] (10.1177/15589447211029045)
  • [L5] The issue surrounding radial tunnel syndrome traditionally has been properly identifying it clinically. [7] (10.1097/01.bth.0000231580.32406.71)
  • [L4] Prospective evaluation of corticosteroid injection demonstrated improvement in standardized outcomes measures of pain and function at one year in 75% of patients presenting with symptoms of radial tunnel syndrome. [8] (10.1016/j.jhsa.2017.06.095)
  • [Paper] Compression of the radial nerve at the elbow is of moderate frequency compared to the ulnar tunnel syndrome. [9] (10.1016/j.main.2004.10.006)
  • [L4] The Rule-of-Nine test effectively specifies the site of tenderness for the diagnosis of radial tunnel syndrome. [11] (10.1177/230949900401200115)
  • [L5] The patient was followed for an additional 3 months, without clinical improvement in radial nerve function. [12] (10.1016/s0363-5023(89)80099-1)
  • [L4] A diagnosis of radial tunnel syndrome should always be born in mind when dealing with patients with forearm and wrist pain that has not responded to more conventional treatment. [13] (10.1016/s0266-7681(05)80152-4)
  • [L5] Radial tunnel syndrome is an illness construct based on a speculative pathophysiology with no verifiable pathophysiology or accepted reference standard for diagnosis. [14] (10.1016/j.jhsa.2010.03.020)
  • [L4] A differential latency of ≥0.30 ms was considered indicative of radial tunnel syndrome. [16] (10.1016/s0363-5023(98)80163-9)
  • [Case_report] The authors advocate for surgery in high radial nerve entrapment neuropathy cases resistant to conservative treatment, emphasizing the importance of dissecting the entire length of the fibrous tunnel. [17] (10.1016/j.jse.2025.02.060)
  • [L4] The results of radial tunnel release have been sufficiently good thus far as to warrant some attention, with an overall significant improvement in 99 of 108 cases (91.7%) when combined with other series. [19] (10.1016/s0363-5023(79)80105-7)
  • [L5] [20] (10.1016/j.jhsa.2009.10.016)
  • [L5] Radial tunnel syndrome is a pain syndrome caused by compression of the posterior interosseous nerve at the proximal forearm. [22] (10.1016/j.ocl.2012.07.022)
  • [L5] It is important to understand the anatomic course and distribution of the radial nerve in order to make an accurate diagnosis. [24] (10.1007/s11420-011-9238-8)
  • [L5] The authors believe that a high rate of morbidity is associated with both the disease and its treatment, suggesting that great caution has to be taken before performing radial tunnel release. [26] (10.1097/00130911-200212000-00010)
  • [L4] Nineteen patients (20 extremities), however, felt satisfied and helped and believed they gained improved function because of surgical decompression of the radial tunnel. [27] (10.1016/s0363-5023(97)80086-x)
  • [L5] Radial tunnel syndrome (RTS) and posterior interosseous nerve (PIN) compression are distinct entities with different clinical presentations but share identical potential sites of nerve interference; the author proposes unifying them as mild (RTS) and severe (PIN compression) forms of one disease to simplify nomenclature. [29] (10.1177/1753193420953990)
  • [L4] Muscle denervation edema or atrophy along the distribution of the posterior interosseous nerve is the most common MR finding in radial tunnel syndrome. [32] (10.1148/radiol.2401050028)
  • [L4] Nerve injury is an uncommon though troublesome complication of fractures or dislocations of the elbow. [39] (10.1016/s0020-1383(79)80015-7)
  • [L4] [48] (10.1016/j.jhsa.2007.10.001)
  • [Paper] The authors acknowledge that their study does not establish diagnostic accuracy or a reference standard for radial tunnel syndrome. [49] (10.1177/17531934261463150)
  • [L4] The authors suggest that great caution be taken before performing radial tunnel release and strict adherence to the indications noted during the preoperative examination. [50] (10.1053/jhsu.1999.0566)
  • [L5] A symptomatic double-level entrapment of the posterior interosseous branch of the radial nerve is described. [51] (10.1016/s0363-5023(83)80202-0)
  • [L5] The authors advocate for consistent use of the terminology distinguishing the deep branch of the radial nerve (DBRN) and the posterior interosseous nerve (PIN), and recommend viewing radial tunnel syndrome and posterior interosseous nerve syndrome as a single condition presenting along a spectrum of nerve entrapment. [52] (10.1177/17531934241254706)
  • [L2] [81] (10.1016/j.jhsa.2024.09.023)
  • [L5] [88] (10.1016/j.jisako.2024.03.001)
  • [L4] This study indicates that pain in patients with radial tunnel syndrome may be treated successfully by surgical decompression of the superficial branch of the radial nerve. [104] (10.1177/1753193408099832)
  • [L5] Supination increases the linear distance between the PIN and radial head and should be considered to increase the safe working volume whenever intra-articular procedures are performed on the anterolateral aspect of the elbow. [107] (10.1016/j.jse.2018.08.019)
  • [L4] Dynamic ultrasonographic assessment of changes in the AP diameter and CSA is an effective diagnostic tool for identifying radial tunnel syndrome. [121] (10.1177/17531934261443138)
  • [L4] Isolated PINN have shown excellent clinical outcomes, with few patients experiencing recurrent pain at long-term follow-up. [123] (10.1177/1558944717692093)
  • [L4] Ultrasonography, computed tomography, and magnetic resonance imaging revealed the location of the ganglion in every patient. [124] (10.1016/s0363-5023(10)80102-9)
  • [L4] Neuroimaging should be considered as a complementary diagnostic method in PINS. [132] (10.1212/wnl.0000000000003287)
  • [L4] In the third patient, in whom the duration of entrapment was more than two years, a tendon transfer was used as treatment. [139] (10.2106/00004623-197355040-00009)

References

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[2] Radial tunnel syndrome: A spectrum of clinical presentations. The Journal of Hand Surgery. 1983. DOI: 10.1016/s0363-5023(83)80201-9

[3] Management of Radial Tunnel Syndrome: A Therapist's Clinical Perspective. Journal of Hand Therapy. 2006. DOI: 10.1197/j.jht.2006.02.020

[4] Radial Tunnel Syndrome: Review and Best Evidence. Journal of the American Academy of Orthopaedic Surgeons. 2023. DOI: 10.5435/jaaos-d-23-00314

[5] Radial Tunnel Syndrome: Diagnosis and Management. Journal of Hand Surgery. 1998. DOI: 10.1016/s0266-7681(98)80015-6

[6] Radial Tunnel Syndrome: Case Report and Comprehensive Critical Review of a Compression Neuropathy Surrounded by Controversy. HAND. 2021. DOI: 10.1177/15589447211029045

[7] A Unified Approach to Radial Tunnel Syndrome and Lateral Tendinosis. Techniques in Hand & Upper Extremity Surgery. 2006. DOI: 10.1097/01.bth.0000231580.32406.71

[8] Prospective Evaluation of Single Corticosteroid Injection in Radial Tunnel Syndrome. The Journal of Hand Surgery. 2017. DOI: 10.1016/j.jhsa.2017.06.095

[9] Compressions du nerf radial au coude. Chirurgie de la Main. 2004. DOI: 10.1016/j.main.2004.10.006

[11] A New Clinical Test for Radial Tunnel Syndrome—The Rule-of-Nine Test: A Cadaveric Study. Journal of Orthopaedic Surgery. 2001. DOI: 10.1177/230949900401200115

[12] Congenital compression of the radial nerve. The Journal of Hand Surgery. 1989. DOI: 10.1016/s0363-5023(89)80099-1

[13] Radial Tunnel Syndrome. Journal of Hand Surgery. 1995. DOI: 10.1016/s0266-7681(05)80152-4

[14] Radial Tunnel Syndrome. The Journal of Hand Surgery. 2010. DOI: 10.1016/j.jhsa.2010.03.020

[16] Differential latency testing: A more sensitive test for radial tunnel syndrome. The Journal of Hand Surgery. 1998. DOI: 10.1016/s0363-5023(98)80163-9

[17] High radial nerve entrapment neuropathy: an anatomical cadaver study and case report. Journal of Shoulder and Elbow Surgery. 2025. DOI: 10.1016/j.jse.2025.02.060

[19] The radial tunnel syndrome. The Journal of Hand Surgery. 1979. DOI: 10.1016/s0363-5023(79)80105-7

[20] Unusual Compression Neuropathies of the Forearm, Part I: Radial Nerve. The Journal of Hand Surgery. 2009. DOI: 10.1016/j.jhsa.2009.10.016

[22] Radial Tunnel Syndrome. Orthopedic Clinics of North America. 2012. DOI: 10.1016/j.ocl.2012.07.022

[24] Posterior Interosseous Neuropathy: Electrodiagnostic Evaluation. HSS Journal®: The Musculoskeletal Journal of Hospital for Special Surgery. 2012. DOI: 10.1007/s11420-011-9238-8

[26] Radial Tunnel Syndrome. Techniques in Hand and Upper Extremity Surgery. 2002. DOI: 10.1097/00130911-200212000-00010

[27] Radial tunnel syndrome: Long-term results of surgical decompression. The Journal of Hand Surgery. 1997. DOI: 10.1016/s0363-5023(97)80086-x

[29] Radial tunnel syndrome: definition, distinction and treatments. Journal of Hand Surgery (European Volume). 2020. DOI: 10.1177/1753193420953990

[32] MR Imaging Features of Radial Tunnel Syndrome: Initial Experience. Radiology. 2006. DOI: 10.1148/radiol.2401050028

[39] Acute nerve injury as a complication of closed fractures or dislocations of the elbow. Injury. 1979. DOI: 10.1016/s0020-1383(79)80015-7

[48] Interventions for Treating the Radial Tunnel Syndrome: A Systematic Review of Observational Studies. The Journal of Hand Surgery. 2008. DOI: 10.1016/j.jhsa.2007.10.001

[49] Re: Role of high-resolution dynamic ultrasonography in the evaluation of posterior interosseous nerve compression at radial tunnel: a prospective case-control study. Journal of Hand Surgery (European Volume). 1934. DOI: 10.1177/17531934261463150

[50] Results of surgical treatment for radial tunnel syndrome. The Journal of Hand Surgery. 1999. DOI: 10.1053/jhsu.1999.0566

[51] Double-entrapment radial tunnel syndrome. The Journal of Hand Surgery. 1983. DOI: 10.1016/s0363-5023(83)80202-0

[52] Nomenclature of the radial nerve: distinguishing between the deep branch of the radial nerve and the posterior interosseous nerve. Journal of Hand Surgery (European Volume). 2024. DOI: 10.1177/17531934241254706

[63] Orthopaedic Knowledge Update 13 Ebook Without Multimedia. Anatomy, Biomechanics, Physical Examination, and Imaging of the Elbow > Anatomy > Bony Anatomy.

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[88] Current concepts of surgical approach for radial nerve entrapment around the elbow. Journal of ISAKOS. 2024. DOI: 10.1016/j.jisako.2024.03.001

[104] Radial Tunnel Syndrome: Emphasis on the Superficial Branch of the Radial Nerve. Journal of Hand Surgery (European Volume). 2009. DOI: 10.1177/1753193408099832

[107] The posterior interosseous nerve crosses the radial head midline and increases its distance from bony structures with supination of the forearm. Journal of Shoulder and Elbow Surgery. 2019. DOI: 10.1016/j.jse.2018.08.019

[121] Role of high-resolution dynamic ultrasonography in the evaluation of posterior interosseous nerve compression at radial tunnel: a prospective case-control study. Journal of Hand Surgery (European Volume). 2026. DOI: 10.1177/17531934261443138

[123] Outcomes Following Isolated Posterior Interosseous Nerve Neurectomy: A Systematic Review. HAND. 2017. DOI: 10.1177/1558944717692093

[124] Diagnosis of radial nerve palsy caused by ganglion with use of different imaging techniques. The Journal of Hand Surgery. 1991. DOI: 10.1016/s0363-5023(10)80102-9

[132] Posterior interosseous neuropathy. Neurology. 2016. DOI: 10.1212/wnl.0000000000003287

[139] Posterior Interosseous-Nerve Syndrome Secondary to Rheumatoid Synovitis. The Journal of Bone & Joint Surgery. 1973. DOI: 10.2106/00004623-197355040-00009

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