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Hội chứng ống khuỷu

Cubital tunnel syndrome causes ulnar nerve compression at the elbow — symptoms, diagnosis, and treatment options.

Updated Jun 2026
Một minh họa vẽ tay của một người không có khuôn mặt, với khuỷu tay cong, đang rung các ngón tay út và ngón áp út của bàn tay do cảm giác tê bì.
Hội chứng ống khuỷu: chèn ép dây thần kinh trụ tại khuỷu tay bên trong. Kieran Hirpara 4.0

Trang này được dịch bằng máy và chưa được bác sĩ kiểm tra. Bản tiếng Anh là bản chính thức.

Những gì bạn đang cảm thấy

Bạn có thể đang trải qua tình trạng đau, tê bì hoặc mất cảm giác ở ngón tay áp út và ngón út. Điều này xảy ra do dây thần kinh trụ bị chèn ép tại khuỷu tay. Tình trạng này được gọi là hội chứng ống khuỷu. Đây là dạng chèn ép phổ biến nhất đối với dây thần kinh cụ thể này. Đây cũng là vấn đề chèn ép dây thần kinh phổ biến thứ hai ở cánh tay trên của bạn.

Sự khó chịu thường trở nên nghiêm trọng hơn khi bạn gập khuỷu tay trong thời gian dài. Bạn có thể nhận thấy nó tăng lên khi ngủ với cánh tay cuộn lại. Nhiều bệnh nhân thấy rằng các triệu chứng bùng phát vào ban đêm hoặc khi thức dậy. Việc với tay ra sau lưng để cài áo ngực có thể trở nên khó khăn. Việc nhét áo vào quần cũng có thể kích hoạt cơn đau hoặc yếu cơ. Bạn có thể cảm thấy cảm giác bất ổn hoặc vụng về ở bàn tay.

Nam giới mắc tình trạng này có nhiều khả năng nhận thấy sự teo cơ ở bàn tay. Đây được gọi là teo cơ. Nó xảy ra thường xuyên hơn ở nam giới so với phụ nữ. Tình trạng này cũng có thể ảnh hưởng đến những người phải đối mặt với khó khăn về kinh tế. Những bệnh nhân này thường cần phẫu thuật ở độ tuổi sớm hơn những người khác.

Nếu các triệu chứng của bạn ở mức độ nhẹ hoặc trung bình, bạn có thể được hưởng lợi từ các phương pháp điều trị không phẫu thuật. Phần lớn bệnh nhân có mức độ nghiêm trọng như vậy sẽ cải thiện mà không cần phẫu thuật. Tuy nhiên, nếu bạn là trẻ em hoặc thiếu niên, tình trạng này rất hiếm. Điều trị không phẫu thuật khó có thể làm thuyên giảm các triệu chứng ở bệnh nhân trẻ tuổi.

Bác sĩ phẫu thuật của bạn sẽ thảo luận về chẩn đoán dựa trên xác suất thay vì sự chắc chắn. Không có xét nghiệm đơn lẻ nào xác nhận tình trạng này với độ chính xác 100%. Đánh giá lâm sàng là phần quan trọng nhất của việc chẩn đoán. Gần bốn mươi phần trăm bệnh nhân có chẩn đoán sơ bộ đã có các vấn đề về dây thần kinh khác hoặc kết quả xét nghiệm bình thường. Nếu các triệu chứng của bạn nghiêm trọng, bạn có thể được hưởng lợi từ việc giới thiệu sớm hơn để đánh giá phẫu thuật tay.

Những gì thực sự đang xảy ra

Hội chứng ống khuỷu tay xảy ra khi dây thần kinh trụ bị chèn ép hoặc kéo căng tại khuỷu tay. Dây thần kinh này chạy từ cổ xuống bàn tay. Nó đi qua một ống hẹp ở mặt trong khuỷu tay. Hãy tưởng tượng ống này giống như một ống tay áo chật. Khi không gian bên trong thu hẹp, dây thần kinh mất đi khả năng di chuyển tự do.

Khuỷu tay của bạn không chỉ là một khớp bản lề đơn giản. Đó là một khớp phức tạp nơi xương và mô mềm tương tác với nhau. Khi bạn gập cánh tay, hình dạng khuỷu tay thay đổi. Xương bên trong ống đẩy vào không gian, làm hẹp thêm không gian này. Sự thay đổi động này gây áp lực lên dây thần kinh. Ngay cả khi bạn không gập cánh tay hoàn toàn, việc gập lặp đi lặp lại vẫn có thể gây tổn thương. Trên thực tế, việc gập một phần lặp đi lặp lại có thể kích thích dây thần kinh nhiều hơn là giữ cánh tay hoàn toàn thẳng hoặc hoàn toàn gập.

Dây thần kinh cũng cần trượt mượt mà khi bạn cử động cổ tay và ngón tay. Nếu vị trí vai của bạn thay đổi, nó sẽ kéo dây thần kinh tại khuỷu tay. Sức căng thêm này làm tăng gánh nặng lên một vùng đã nhạy cảm. Ở một số người, một cơ phụ hoặc dây chằng lỏng lẻo tạo thêm áp lực. Điều này ít phổ biến hơn, nhưng nó có thể làm dây thần kinh bị kẹt thêm.

Khi dây thần kinh bị chèn ép, nó không thể truyền tín hiệu đúng cách. Điều này dẫn đến cảm giác tê, kiến bò hoặc yếu mà bạn cảm thấy ở ngón áp út và ngón út. Vấn đề không chỉ là áp lực tĩnh. Đó là sự kết hợp của việc chèn ép, kéo căng và giảm lưu lượng máu đến dây thần kinh. Hiểu điều này giúp bác sĩ phẫu thuật lựa chọn phương pháp điều trị phù hợp. Phẫu thuật nhằm tạo thêm không gian để dây thần kinh có thể di chuyển tự do trở lại.

Những gì chúng tôi có thể làm về vấn đề này

Hầu hết bệnh nhân có triệu chứng nhẹ hoặc trung bình tìm thấy sự giảm nhẹ thông qua điều trị bảo tồn. Hành trình của bạn thường bắt đầu với tự quản lý và vật lý trị liệu. Bạn có thể được khuyên tránh tì khuỷu tay hoặc giữ khuỷu tay ở tư thế gập trong thời gian dài. Vật lý trị liệu nhằm mục đích giảm kích thích và cải thiện sự di chuyển của dây thần kinh. Cách tiếp cận này khó có thể làm hết triệu chứng ở bệnh nhân nhi và thiếu niên, do đó trẻ em có thể cần một hướng điều trị khác. Hãy cho điều trị không phẫu thuật một cơ hội công bằng trước khi xem xét các lựa chọn khác.

Quản lý y khoa tập trung vào kiểm soát đau và viêm. Bác sĩ phẫu thuật của bạn có thể khuyên dùng thuốc giảm đau hoặc thuốc chống viêm để giúp bạn quản lý các hoạt động hàng ngày. Mặc dù bằng chứng không nêu chi tiết các loại tiêm cụ thể như cortisone, axit hyaluronic hoặc PRP cho tình trạng này, bác sĩ lâm sàng của bạn sẽ thảo luận về những gì phù hợp với trường hợp của bạn. Mục tiêu là làm dịu dây thần kinh bị kích thích để bạn có thể tham gia vào liệu pháp. Lưu ý rằng gần bốn mươi phần trăm bệnh nhân có chẩn đoán sơ bộ có một bệnh lý dây thần kinh khác hoặc kết quả dẫn truyền thần kinh bình thường, do đó chẩn đoán chính xác là chìa khóa trước khi bắt đầu dùng thuốc.

Nếu chăm sóc bảo tồn đạt đến giới hạn, phẫu thuật có thể được xem xét. Phẫu thuật hiệu quả trong điều trị hội chứng khe khuỷu, với hơn 90% bệnh nhân được chữa khỏi hoặc cải thiện. Không có sự đồng thuận về phương pháp phẫu thuật đơn lẻ tốt nhất, và hầu hết các bác sĩ phẫu thuật sử dụng nhiều hơn một thủ thuật phẫu thuật dựa trên các yếu tố cụ thể của bạn. Một nhóm nhỏ bệnh nhân có thể được hưởng lợi từ việc giới thiệu sớm để đánh giá phẫu thuật tay. Phẫu thuật lại sau phẫu thuật ban đầu mang lại kết quả thỏa mãn cho những người thất bại trong điều trị bảo tồn. Bác sĩ phẫu thuật của bạn sẽ thảo luận về cách tiếp cận tốt nhất cho bạn, lưu ý rằng đánh giá lâm sàng là yếu tố quan trọng nhất trong chẩn đoán.

Những điều cần biết

Hội chứng khe khuỷu thường phát triển chậm. Bạn có thể nhận thấy các triệu chứng sớm hơn so với người mắc hội chứng ống cổ tay, nhưng tình trạng này có xu hướng tiến triển chậm hơn. Đối với nhiều người, tình trạng này không tự thuyên giảm. Một nhóm bệnh nhân có thể được hưởng lợi từ việc chuyển tuyến sớm để đánh giá bởi bác sĩ phẫu thuật tay và phẫu thuật sớm hơn. Điều này có thể giúp ngăn ngừa tổn thương thần kinh lâu dài.

Phẫu thuật nói chung có hiệu quả. Hơn 90% bệnh nhân được chữa khỏi hoặc cải thiện sau khi điều trị. Bác sĩ phẫu thuật của bạn sẽ nhằm mục đích giảm áp lực lên thần kinh trụ. Đây là thần kinh chạy qua khuỷu tay. Các triệu chứng phân bố ngoài thần kinh trụ có thể thuyên giảm sau khi giải phóng khe khuỷu. Kết quả báo cáo bởi bệnh nhân là tốt, nhưng chúng bị ảnh hưởng bởi mức độ nghiêm trọng của các triệu chứng trước phẫu thuật. Nếu bạn đã có các triệu chứng trong thời gian dài, quá trình hồi phục có thể cảm thấy khác so với người mới khởi phát.

Biến chứng là không phổ biến. Tỷ lệ biến chứng ngắn hạn của phẫu thuật khe khuỷu thấp (3,2%). Tuy nhiên, các tỷ lệ này cao hơn ở những bệnh nhân mắc bệnh thận mạn tính. Bác sĩ phẫu thuật của bạn sẽ cẩn thận tránh các phẫu thuật chỉnh sửa không cần thiết bằng cách chú ý kỹ lưỡng đến các cấu trúc gần khuỷu tay.

Nếu bạn cần phẫu thuật lại, kết quả kém dự đoán và ít hài lòng hơn so với phẫu thuật lần đầu. Phẫu thuật lại sau phẫu thuật lần đầu cho hội chứng khe khuỷu mang lại kết quả thỏa mãn cho những bệnh nhân thất bại với điều trị bảo tồn, nhưng kết quả không được đảm bảo. Hiện tại chưa có sự đồng thuận về phương pháp phẫu thuật tốt nhất cho hội chứng khe khuỷu. Bác sĩ phẫu thuật của bạn sẽ chọn một phương pháp dựa trên giải phẫu cụ thể của bạn và kinh nghiệm của họ.

Quá trình hồi phục diễn ra dần dần. Bạn có thể nhận thấy sự cải thiện triệu chứng nhanh hơn nếu bạn có một cơ dị dạng ở cánh tay. Hầu hết mọi người trở lại các hoạt động bình thường khi cơn đau giảm đi. Tuy nhiên, không có sự khác biệt đáng kể về kết quả dài hạn sau khi giải nén tại chỗ mở và nội soi bằng dụng cụ giữ mô (retractor-endoscopic) cho thần kinh trụ trong hội chứng khe khuỷu. Mục tiêu là khôi phục chức năng và giảm khó chịu. Với việc chăm sóc thích hợp, bạn có thể mong đợi chất lượng cuộc sống tốt sau khi điều trị.

Khi nào cần gặp bác sĩ

Hãy gặp bác sĩ đa khoa nếu bạn có cơn đau dai dẳng không cải thiện khi nghỉ ngơi. Hãy yêu cầu đánh giá bởi bác sĩ chuyên khoa nếu bạn nhận thấy tình trạng yếu hoặc mất ổn định ở bàn tay. Hội chứng ống khuỷu là dạng chèn ép dây thần kinh trụ phổ biến nhất. Đây cũng là hội chứng chèn ép dây thần kinh phổ biến thứ hai ở chi trên. Bạn có thể đến khám sớm hơn trong tiến trình bệnh so với những bệnh nhân mắc hội chứng ống cổ tay. Các triệu chứng ảnh hưởng đến giấc ngủ hoặc công việc là dấu hiệu rõ ràng để tìm kiếm sự giúp đỡ. Đa số bệnh nhân có triệu chứng nhẹ hoặc trung bình đều được hưởng lợi từ điều trị bảo tồn. Tuy nhiên, việc đánh giá lâm sàng là yếu tố then chốt vì các xét nghiệm điện sinh lý thường không đủ nhạy cảm. Chẩn đoán nên được thảo luận dựa trên xác suất thay vì sự chắc chắn tuyệt đối.


Evidence & references

Overview

  • Cubital tunnel syndrome involves related anatomy, clinical presentation, and current management options [1].
  • A subset of patients with cubital tunnel syndrome may benefit from earlier referral for hand surgery evaluation and earlier surgery [2].
  • Patient-reported outcomes of surgical treatment for cubital tunnel syndrome are good but are affected by preoperative symptom severity [4].
  • Surgery is effective in treating cubital tunnel syndrome, with more than 90% of patients cured or showing improvement [5].
  • More rigorous scientific studies are needed to determine the most effective surgical approaches for cubital tunnel syndrome [6].
  • A treatment algorithm has been proposed to provide clarity about the challenges of treating the complex patient population with cubital tunnel syndrome [7].
  • There is currently no consensus on the best surgical treatment of cubital tunnel syndrome [8].
  • Carpal tunnel and cubital tunnel syndrome requiring surgery is more common in deprived patients and occurs at an earlier age [12].
  • Endoscopic cubital tunnel decompression has gained popularity, with early short-term results showing satisfactory outcomes and minimal complications [14].
  • The selection of operative procedures for cubital tunnel syndrome is influenced by patient factors and surgeon preference, with most surgeons using more than one operative procedure [29].

Anatomy & Pathophysiology

  • Definitions for the degree of ulnar nerve instability at the elbow are not uniformly agreed upon [28].
  • With elbow flexion, the ulnar nerve did not move appreciably in the distal–proximal direction directly at the cubital tunnel [49].
  • Maximal ulnar nerve excursion during elbow flexion occurs in the fatty region proximal to the elbow [49].
  • The humeral trochlea protrudes into the cubital tunnel during elbow flexion, causing dynamic morphologic changes in the ulnar nerve [50].
  • Tearing of the ulnar collateral ligament significantly increases elbow valgus laxity, which elongates the ulnar nerve during simulated throwing motion [51].
  • Increased elbow flexion influences the intraneural blood flow of the ulnar nerve in patients with cubital tunnel syndrome [57].
  • Exposure to lesser extraneural pressure by repetitive non-maximum elbow flexion might be more deleterious than maximum flexion pressure in cubital tunnel syndrome [55].
  • Shoulder position changes the ulnar nerve strain around the elbow in living patients with cubital tunnel syndrome [56].
  • The mechanism of symptom provocation by the elbow flexion test cannot be explained simply by dynamic pressure in the cubital tunnel, suggesting other pathophysiological factors contribute [58].
  • Ulnar nerve gliding is most severe during passive wrist movement in elbow flexion and forearm supination [59].
  • The study could not detect a definitive effect of elbow deformity (cubitus valgus/varus) on ulnar nerve strain or demonstrate the extent of acceptable clinical elbow deformity [61].
  • The throwing elbow is a common source of nerve injuries due to the unique combination of anatomy, high forces, and sheer repetition associated with throwing sports [62].
  • Dynamic ulnar nerve compression at the elbow due to the anconeus epitrochlearis muscle is an uncommon disorder with much remaining to be elucidated about its incidence and pathophysiologic mechanisms [64].

Classification

  • Cubital tunnel syndrome is the most common form of entrapment of the ulnar nerve [18].
  • Cubital tunnel syndrome is the second most common nerve compression syndrome of the upper extremity [18].
  • Definitions for the degree of ulnar nerve instability at the elbow are not uniformly agreed upon [28].
  • Further development of a classification system for ulnar nerve instability may be warranted to standardize treatment [28].
  • High-resolution ultrasound (HRU) shows good correspondence to clinical and ENMG classifications in cubital tunnel syndrome [35].
  • An intraoperative ulnar nerve subluxation classification system has promise in preventing adverse complications of ulnar nerve hypermobility after endoscopic cubital tunnel release [43].

Clinical Presentation

  • Cubital tunnel syndrome is the most common form of entrapment of the ulnar nerve [18].
  • Cubital tunnel syndrome is the second most common nerve compression syndrome of the upper extremity [18].
  • Patients with cubital tunnel syndrome present earlier in the course of their disease than patients with carpal tunnel syndrome [3].
  • Men with cubital tunnel syndrome are more likely to present with muscle atrophy than women [10].
  • Carpal tunnel and cubital tunnel syndrome requiring surgery is more common in deprived patients and occurs at an earlier age [12].
  • The majority of patients suffering from cubital tunnel syndrome with mild or moderate symptoms benefit from conservative treatment [20].
  • Cubital tunnel syndrome in pediatric or adolescent patients is rare [19].
  • Non-operative treatment of cubital tunnel syndrome in pediatric and adolescent patients is unlikely to resolve symptoms [22].
  • There is no consensus reference standard for the diagnosis of Cubital Tunnel Syndrome [11].
  • Provocative tests for Cubital Tunnel Syndrome have inadequate or inconsistent sensitivity and specificity [11].
  • Diagnosis of Cubital Tunnel Syndrome should be discussed in terms of probabilities rather than certainties [11].
  • Clinical evaluation is paramount in the diagnosis of cubital tunnel syndrome because electrodiagnostic testing often is not sufficiently sensitive to detect changes associated with the syndrome [17].
  • Nearly forty percent of patients with a provisional diagnosis of Cubital Tunnel Syndrome had either another nerve pathology or a normal nerve conduction study [21].

Investigations

  • Provocative tests for cubital tunnel syndrome have inadequate or inconsistent sensitivity and specificity [11].
  • There is no consensus reference standard for the diagnosis of cubital tunnel syndrome [11].
  • Diagnosis of cubital tunnel syndrome should be discussed in terms of probabilities rather than certainties [11].
  • Electrodiagnostic testing is often not sufficiently sensitive to detect changes associated with cubital tunnel syndrome [17].
  • Clinical evaluation is paramount in the diagnosis of cubital tunnel syndrome [17].
  • Nearly forty percent of patients with a provisional diagnosis of cubital tunnel syndrome had either another nerve pathology or a normal nerve conduction study [21].
  • Ulnar nerve cross-sectional area (CSA) measured by ultrasound is useful for the diagnosis of cubital tunnel syndrome [47].
  • Ulnar nerve CSA measured by ultrasound is most significantly different between patients and controls at the medial epicondyle [47].
  • Power Doppler ultrasound has high predictive value for severe cubital tunnel syndrome defined by axonal loss [54].
  • MRI is an effective diagnostic modality for identifying primary synovial chondromatosis as a causative factor of cubital tunnel syndrome [38].
  • Only a small number of individuals with MRI evidence of an anconeus epitrochlearis muscle (AEM) had clinical evidence of ulnar neuropathy [48].
  • Cubital tunnel decompression is associated with prior trauma to the anatomic site [53].

Treatment

Non-Operative Management

  • The majority of patients with mild or moderate cubital tunnel syndrome symptoms benefit from conservative treatment [20].
  • Non-operative treatment is unlikely to resolve symptoms in pediatric and adolescent patients [22].

Operative Management: General Principles and Selection

  • There is currently no consensus on the best surgical treatment for cubital tunnel syndrome [8].
  • Most surgeons use more than one operative procedure for cubital tunnel syndrome, with selection influenced by patient factors and surgeon preference [29].
  • Surgery is effective in treating cubital tunnel syndrome, with more than 90% of patients cured or showing improvement [5].
  • None of the surgical techniques has demonstrated universal superiority above all others, but all appear to be effective [41].
  • A subset of patients may benefit from earlier referral for hand surgery evaluation and earlier surgery [2].
  • Reoperation after primary surgery provides satisfactory results for patients who fail conservative treatment [15].
  • In situ decompression of the ulnar nerve is a reliable treatment with a low failure rate [40].

Operative Techniques: Decompression

  • Simple decompression with a small skin incision yielded satisfactory results in 14 of 18 elbows with no postoperative dislocation of the ulnar nerve [32].
  • Endoscopic and open in situ decompression techniques demonstrate similar effectiveness, outcomes, complication profiles, and reoperation rates for idiopathic cubital tunnel syndrome [39].
  • The patient-reported outcome of surgical treatment is good but is affected by preoperative symptom severity [4].

Operative Techniques: Transposition and Other Procedures

  • Both minimal medial epicondylectomy and anterior subcutaneous transposition can be used for cubital tunnel syndrome with a high rate of satisfaction [37].
  • Medial epicondylectomy is recommended for patients with cubital tunnel syndrome associated with abnormal nerve-conduction velocity [33].
  • The procedure offers complete release of constricting structures while preserving blood supply to the nerve and allowing early postoperative elbow mobilization [25].

Operative Techniques: Specialized and Combined Procedures

  • Bony encasement of the ulnar nerve secondary to heterotopic ossification of the elbow is treated with an approach that leads to superior range of motion, improved or resolved ulnar neuropathy, and good to excellent long-term functional outcomes [26].
  • Dual endoscopic carpal and cubital tunnel release is a safe and effective treatment option for patients with concurrent syndromes recalcitrant to nonsurgical management [36].

Complications

  • Surgery was effective in treating cubital tunnel syndrome with more than 90% of patients cured or showing improvement [5].
  • The short-term complication rates of cubital tunnel surgery are low (3.2%) [24].
  • Short-term complication rates for cubital tunnel surgery are higher for patients with chronic kidney disease [24].
  • Endoscopic cubital tunnel decompression shows satisfactory outcomes and minimal complications [14].
  • Reoperation after primary surgery of cubital tunnel syndrome gave satisfactory results for patients who fail conservative treatment [15].
  • Results of revision surgery for recurrent or persistent cubital tunnel syndrome are less predictable and satisfying than primary surgery [31].
  • Poor outcomes and unnecessary revision surgeries for cubital tunnel syndrome can be avoided with intraoperative attention to 7 structures distal to the medial epicondyle [44].

Recovery

  • Patients with carpal tunnel syndrome present earlier in the course of their disease than patients with cubital tunnel syndrome [3].
  • A subset of patients with cubital tunnel syndrome may benefit from earlier referral for hand surgery evaluation and earlier surgery [2].
  • The patient-reported outcome of surgical treatment of cubital tunnel syndrome is good but is affected by preoperative symptom severity [4].
  • Surgery was effective in treating cubital tunnel syndrome with more than 90% of patients cured or showing improvement [5].
  • Symptoms in an extra-ulnar distribution can resolve following cubital tunnel release [9].
  • Reliable, reproducible, and valid outcomes measures are lacking from the surgical literature for cubital tunnel syndrome [13].
  • Endoscopic cubital tunnel decompression shows satisfactory outcomes and minimal complications in early short-term results [14].
  • Reoperation after primary surgery of cubital tunnel syndrome gave satisfactory results for patients who fail conservative treatment [15].
  • The short-term complication rates of cubital tunnel surgery are low (3.2%), but higher for patients with chronic kidney disease [24].
  • Treatment of bony encasement of the ulnar nerve secondary to heterotopic ossification leads to superior range of motion, improved or resolved ulnar neuropathy, and good to excellent long-term functional outcomes [26].
  • There are no significant differences in long-term outcomes after open and retractor-endoscopic in situ decompression of the ulnar nerve in cubital tunnel syndrome [30].
  • Results of revision surgery for recurrent or persistent cubital tunnel syndrome are less predictable and satisfying than primary surgery [31].
  • Patients with an anomalous muscle (AE) experience quicker symptom improvement after cubital tunnel release than those without the anomalous muscle [34].

Key Evidence

  • [L5] This article reviews related anatomy, clinical presentation, and current management options for cubital tunnel syndrome with an emphasis on contemporary outcomes research. [1] (10.1016/j.jhsa.2015.03.011)
  • [L3] A subset of patients with cubital tunnel syndrome may benefit from earlier referral for hand surgery evaluation and earlier surgery. [2] (10.1177/15589447211058821)
  • [L4] Patients with carpal tunnel syndrome present earlier in the course of their disease than patients with cubital tunnel syndrome. [3] (10.1016/j.jhsa.2007.03.009)
  • [L3] The patient-reported outcome of surgical treatment of cubital tunnel syndrome is good but is affected by preoperative symptom severity. [4] (10.1016/j.jhsa.2009.05.014)
  • [L4] Surgery was effective in treating cubital tunnel syndrome with more than 90% of patients cured or showing improvement. [5] (10.1016/j.otsr.2014.03.009)
  • [L4] More rigorous scientific studies are needed to determine the most effective surgical approaches for cubital tunnel syndrome. [6] (10.1007/s12178-020-09650-y)
  • [L4] The purpose of this review is to summarize the most up-to-date literature regarding cubital tunnel syndrome and propose a treatment algorithm to provide clarity about the challenges of treating this complex patient population. [7] (10.1016/j.jhsg.2022.07.008)
  • [L5] There is currently no consensus on the best surgical treatment of cubital tunnel syndrome. [8] (10.1016/j.ocl.2012.07.017)
  • [L3] This study documents resolution of symptoms in an extra-ulnar distribution after cubital tunnel release. [9] (10.1007/s11552-014-9688-9)
  • [L4] Men with cubital tunnel syndrome are more likely to present with muscle atrophy than women. [10] (10.1177/1558944716643096)
  • [L4] There is no consensus reference standard for the diagnosis of Cubital Tunnel Syndrome, and provocative tests have inadequate or inconsistent sensitivity and specificity; diagnosis should be discussed in terms of probabilities rather than certainties. [11] (10.1016/j.jhsa.2011.03.021)
  • [L4] Carpal tunnel and cubital tunnel syndrome requiring surgery is more common in deprived patients and occurs at an earlier age. [12] (10.1177/1753193420939384)
  • [L3] Reliable, reproducible, and valid outcomes measures are lacking from the surgical literature for cubital tunnel syndrome. [13] (10.1016/j.jhsa.2009.05.010)
  • [L5] Endoscopic cubital tunnel decompression has gained popularity with early short-term results being encouraging, showing satisfactory outcomes and minimal complications. [14] (10.1136/jisakos-2020-000506)
  • [L4] Clinical evaluation is paramount in the diagnosis of cubital tunnel syndrome because electrodiagnostic testing often is not sufficiently sensitive to detect changes associated with the syndrome. [17] (10.1016/j.hcl.2013.08.019)
  • [L5] Cubital tunnel syndrome is the most common form of entrapment of the ulnar nerve and the second most common nerve compression syndrome of the upper extremity. [18] (10.1016/s0749-0712(21)00356-5)
  • [L3] Cubital tunnel syndrome in pediatric or adolescent patients is rare and can be treated successfully with surgical intervention. [19] (10.1016/j.jhsa.2012.01.016)
  • [L2] The majority of patients suffering from cubital tunnel syndrome with mild or moderate symptoms benefit from conservative treatment. [20] (10.1177/1753193408098480)
  • [L4] Nearly forty percent of patients with a provisional diagnosis of CubTS had either another nerve pathology or a normal test. [21] (10.1016/j.jse.2020.01.064)
  • [L4] Non-operative treatment of cubital tunnel syndrome in pediatric and adolescent patients is unlikely to resolve symptoms. [22] (10.1016/s0363-5023(11)60063-4)
  • [L4] The short-term complication rates of cubital tunnel surgery are low (3.2%), but higher for patients with chronic kidney disease. [24] (10.1016/j.jhsa.2017.01.020)
  • [L5] The procedure offers complete release of constricting structures while preserving blood supply to the nerve and allowing early postoperative elbow mobilization. [25] (10.1016/s0749-0712(21)00325-5)
  • [L4] This treatment approach leads to superior range of motion, improved or resolved ulnar neuropathy, and good to excellent long-term functional outcomes. [26] (10.1016/j.jse.2023.12.003)
  • [L4] Most surgeons use more than one operative procedure in their treatment of patients with cubital tunnel syndrome and the selection of the operative procedure is influenced by patient factors and surgeon preference. [29] (10.1007/s11552-008-9133-z)
  • [L3] There are no significant differences in long-term outcomes after open and retractor-endoscopic in situ decompression of the ulnar nerve in cubital tunnel syndrome. [30] (10.1227/neu.0b013e3182846dbd)
  • [L4] Results of revision surgery for recurrent or persistent cubital tunnel syndrome are less predictable and satisfying than primary surgery. [31] (10.1016/j.jhsa.2011.11.024)
  • [L4] The technique yielded satisfactory results in 14 of 18 elbows with no postoperative dislocation of the ulnar nerve. [32] (10.1054/jhsb.2002.0821)
  • [L4] The procedure is recommended for patients with cubital tunnel syndrome associated with abnormal nerve-conduction velocity. [33] (10.2106/00004623-198062060-00016)
  • [L3] Patients with an AE experience quicker symptom improvement after cubital tunnel release than those without the anomalous muscle. [34] (10.1016/j.jhsa.2017.06.033)
  • [L4] HRU proved to be an effective diagnostic tool for cubital tunnel syndrome and its etiologies, showing good correspondence to clinical and ENMG classifications. [35] (10.1016/j.otsr.2014.03.008)
  • [L4] Preliminary data demonstrate that dual endoscopic carpal and cubital tunnel release is a safe and effective treatment option for patients who present with concurrent cubital and carpal tunnel syndromes recalcitrant to nonsurgical management. [36] (10.1007/s11552-013-9552-3)
  • [L3] Both methods can be used for the treatment of cubital tunnel syndrome with a high rate of satisfaction. [37] (10.1016/j.jse.2005.10.007)
  • [Case_report] MRI is an effective diagnostic modality, and clinicians should be aware of primary synovial chondromatosis as a causative factor of cubital tunnel syndrome. [38] (10.1177/1758573216683396)
  • [L1] The current study demonstrates similar effectiveness between the endoscopic (ECTuR) and open (OCTuR) techniques for treatment of idiopathic cubital tunnel syndrome with similar outcomes, complication profiles, and reoperation rates. [39] (10.1177/1558944715616097)
  • [L4] In situ decompression of the ulnar nerve is a reliable treatment for cubital tunnel syndrome with a low failure rate. [40] (10.1177/1753193408101467)
  • [L4] None of the techniques in this review has demonstrated universal superiority above all others, but all appear to be effective in the treatment of cubital tunnel syndrome. [41] (10.3389/fsurg.2018.00048)
  • [L4] Our preliminary report of patients shows satisfactory outcomes, which suggests that our intraoperative ulnar nerve subluxation classification system has promise in preventing adverse complications of ulnar nerve hypermobility after endoscopic cubital tunnel release. [43] (10.1016/j.jhsg.2020.05.001)
  • [L5] Poor outcomes and unnecessary revision surgeries for cubital tunnel syndrome can be avoided with intraoperative attention to 7 structures distal to the medial epicondyle. [44] (10.1177/1558944718771390)
  • [L1] The ulnar nerve CSA measured by US imaging is useful for the diagnosis of cubital tunnel syndrome (CuTS), and is most significantly different between patients and controls at the medial epicondyle. [47] (10.1016/j.apmr.2017.08.467)
  • [L4] Only a small number of individuals with MRI evidence of an AEM had clinical evidence of ulnar neuropathy. [48] (10.1016/j.jse.2018.03.021)
  • [L5] With elbow flexion, the ulnar nerve did not move appreciably in the distal–proximal direction directly at the cubital tunnel, but maximal excursion was in the fatty region proximal to the elbow. [49] (10.1016/j.jhsa.2012.03.016)
  • [L5] The humeral trochlea protrudes into the cubital tunnel during elbow flexion, causing dynamic morphologic changes in the ulnar nerve. [50] (10.1016/j.jse.2022.05.026)
  • [L5] Tearing of the UCL significantly increased elbow valgus laxity, which in turn elongated the ulnar nerve during simulated throwing motion. [51] (10.1016/j.jse.2019.02.009)
  • [L4] Cubital tunnel decompression is associated with prior trauma to the anatomic site. [53] (10.1016/j.jhsa.2017.07.009)
  • [L3] Power Doppler ultrasound demonstrated high predictive value for severe cubital tunnel syndrome defined by axonal loss. [54] (10.1177/15589447221127334)
  • [L4] The increased pressure in the cubital tunnel could still be important, as exposure to a lesser extraneural pressure by repetitive non-maximum elbow flexion might be more deleterious. [55] (10.3109/2000656x.2012.747962)
  • [L4] To the best of our knowledge, this is the first study showing that shoulder position changes the ulnar nerve strain around the elbow in living patients with CubTS. [56] (10.1016/j.jse.2015.01.014)
  • [L3] Increased elbow flexion in patients with CuTS influences the intraneural blood flow of the ulnar nerve. [57] (10.1016/j.jhsa.2021.06.024)
  • [L3] The mechanism of provocation of symptoms of cubital tunnel syndrome by the elbow flexion test could not be explained simply by dynamic pressure in the cubital tunnel, and other pathophysiological factors could also be contributing. [58] (10.1016/j.jhsa.2010.11.013)
  • [L4] Ulnar nerve gliding was most severe during passive wrist movement in elbow flexion and forearm supination. [59] (10.5397/cise.2024.00934)
  • [L5] The study could not detect a definitive effect of elbow deformity on ulnar nerve strain or demonstrate the extent of acceptable clinical elbow deformity. [61] (10.1186/s12891-022-05786-9)
  • [L5] The throwing elbow is a common source of nerve injuries due to the unique combination of anatomy, high forces, and sheer repetition associated with throwing sports. [62] (10.1016/j.csm.2004.04.012)
  • [L4] Dynamic ulnar nerve compression at the elbow due to the anconeus epitrochlearis muscle is an uncommon, little-known disorder with much remaining to be elucidated about its incidence and pathophysiologic mechanisms. [64] (10.1016/j.jhsg.2022.11.002)

References

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1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.


Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.