The necessity of electrodiagnostic studies and ultrasound in ulnar nerve entrapment according to surgeons in the Netherlands.

BACKGROUND: Ulnar nerve entrapment at the elbow (UNE) is the second most prevalent entrapment neuropathy after carpal tunnel syndrome. The objective of this study was to evaluate the expert opinion of different surgical disciplines regarding the need for electrodiagnostic or ultrasound confirmation of UNE and, if so, which test was preferred for confirmation. METHODS: A questionnaire was sent to all neurosurgeons and plastic or hand surgeons in the Netherlands to evaluate the current practice in planning surgical treatment of UNE. RESULTS: The response rate was 36.4 % (134 out of 368). 94 % of surgeons reported that > 95 % of their patients had EDX or ultrasound studies before surgery. 80.6 % of all surgeons who responded reported that they seldom operated on UNE without electrodiagnostic confirmation. Hand surgeons (25.9 %) were more willing to operate on clinically diagnosed UNE without EDX than neurosurgeons (9.4 %) CONCLUSIONS: Dutch surgeons prefer diagnostic confirmation of UNE either by ultrasound or EDX, with a preference for EDX and the vast majority of operated patients do have either EDX or ultrasound or both before surgery. Compared to neurosurgeons, hand surgeons are more willing to operate on patients with clinically defined UNE but normal electrodiagnostic studies.

Overuse of the psychoactive analgesics' opioids and gabapentinoid drugs in patients having surgery for nerve entrapment disorders.

Knowledge about risks for overuse of psychoactive analgesics in patients having primary surgery for carpal tunnel syndrome (CTS) or ulnar nerve entrapment (UNE), or both, is limited. We investigated if patients with those nerve entrapment disorders have a higher risk of overuse of psychoactive analgesics (i.e., opioids and gabapentinoid drugs) before, after, and both before and after surgery than observed in the general population after accounting for demographical and socioeconomic factors. Using a large record linkage database, we analysed 5,966,444 individuals (25-80 years), residing in Sweden December 31st, 2010-2014, of which 31,380 underwent surgery 2011-2013 for CTS, UNE, or both, applying logistic regression to estimate relative risk (RR) and 95% confidence interval (CI). Overall, overuse of the psychoactive analgesics was low in the general population. Compared to those individuals, unadjusted RR (95% CI) of overuse ranged in patients between 2.77 (2.57-3.00) with CTS after surgery and 6.21 (4.27-9.02) with both UNE and CTS after surgery. These risks were only slightly reduced after adjustment for demographical and socioeconomic factors. Patients undergoing surgery for CTS, UNE, or both, have a high risk of overuse of psychoactive analgesics before, after, and both before and after surgery.

Ulnar Nerve Compression at the Elbow Secondary to Intramuscular Lipoma of the Flexor Carpi Ulnaris: A Case Report.

CASE: A 62-year-old right-hand-dominant woman presented with 1 year of persistent radiating pain, weakness, and paresthesias in her left forearm and hand. Electromyography findings were significant for ulnar neuropathy distal to the branch innervating the flexor carpi ulnaris (FCU), without superimposed cervical radiculopathy or other focal entrapment neuropathy. During open ulnar nerve neurolysis, an intramuscular lipoma was encountered within the FCU. Lipoma excision and cubital tunnel release with ulnar nerve transposition were performed with complete relief of neuropraxia. CONCLUSION: We demonstrate full neurologic recovery after intramuscular lipoma excision and cubital tunnel release. Although rare, anomalous anatomy and tissue overgrowth should remain on the differential for patients presenting with atypical neuropraxia.

A 10-Year Update of Outcome Measures Used to Assess Results After Surgery for Cubital Tunnel Syndrome: A Systematic Review of the Literature.

HYPOTHESIS: Outcomes reporting for the surgical release of ulnar nerve cubital tunnel entrapment have variability in subjective, objective, and validated measures. The aim of this study is to review the literature to reassess the measures used to report surgical outcomes for ulnar neurolysis at the elbow. METHODS: This study was conducted in accordance with the PRISMA guidelines on systematic reviews. Six electronic databases were queried from the past 10 years using specific search terms and Boolean operators. Two independent reviewers assessed 4290 unique titles and abstracts that were screened for inclusion criteria. Sixty-eight full text articles were included for analysis. RESULTS: Statistical significance was noted in the number of outcome measures reported between studies from journals of impact factor within the first and third quartiles (P = 0.0086) and first and fourth quartiles (P = 0.0247), although no significance exists in the number of cubital tunnel-specific measures based on impact factor (P = 0.0783). Seventy-nine percent (n = 54) of the included studies report subjective measures; 54% (n = 37) included objective measures. Seventy percent (n = 48) of the studies report disease-specific outcome measures. CONCLUSION: There exists a discordance within the literature regarding the most appropriate, descriptive, and translational measures for reporting surgical outcomes of cubital tunnel syndrome. We recommend journal editors implement a requirement that authors reporting outcomes of ulnar nerve decompression must use a standard, validated measure to make comparisons across the literature universal. Furthermore, a minimum of at least 1 subjective and 1 objective measure should be standard.

Median and Ulnar Nerve Compressions: Simplifying Diagnostics and Surgery at the Elbow and Hand.

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Understand the anatomy of the median and ulnar nerves. 2. Perform clinical examination of the upper limb. 3. Analyze examination results to diagnose level of nerve compression. SUMMARY: Numbness and loss of strength are common complaints in the hand surgery clinic. Two nerves that are commonly entrapped (median and ulnar nerves) have several potential sites of entrapment, and in busy clinical practice, the less common sites may be overlooked, leading to wrong or missed diagnoses. This article reviews the anatomy of the median and ulnar nerves, provides tips to assist the busy clinician in diagnosis of site of entrapment(s), and discusses how to simplify surgery. The goal is to help the clinician be as efficient and accurate as possible when evaluating the patient with numbness or loss of strength in their hand.

Cost of surgical treatment for ulnar nerve entrapment in Finland, 2011-2015: a registry-based cost description study.

OBJECTIVES: The aim of this study was to evaluate the cost of surgical treatment for primary ulnar nerve entrapment (UNE) borne by the public sector in Finland. DESIGN: Registry-based cost description study. SETTING: Primary and secondary care throughout Finland. PARTICIPANTS: We identified all the patients diagnosed with primary UNE in the whole population of Finland from 2011 to 2015 from the Care Register for Health Care. From these patients, we identified those who had undergone ulnar nerve release during the year they were diagnosed or the following year. INTERVENTIONS: Open ulnar nerve release. OUTCOME MEASURES: The primary outcome measure was cost borne by the public sector in 2015 euros. The cost of surgery was based on the diagnosis-related group prices. We calculated the cost of a single visit to a primary care physician, an electroneuromyography examination, a preoperative visit to a hand surgeon and a follow-up appointment by telephone in specialised care for each patient. These unit costs were provided by the Finnish Institute for Health and Welfare and the same costs were used for each patient. We obtained the number of reimbursed sick days and the total amount reimbursed to each patient in euros within the 2 years after diagnosis from the Social Insurance Institution of Finland. RESULTS: During our study period, approximately 1786 primary UNE diagnoses were made yearly, and on average, 876 (49%) of patients received surgical treatment annually. The surgery-related cost per patient averaged at EUR 1341 (43%) and reimbursed sick leaves at EUR 952 (30%) during this period. The annual cost of surgical treatment for UNE borne by the public sector in Finland varied between EUR 3082 and EUR 3213 per patient. CONCLUSIONS: The average cost of surgical treatment for UNE in Finland was EUR 3140 per patient between 2011 and 2015.

Myofibroma mimicking peripheral nerve sheath tumour with ulnar nerve compression symptoms.

We report a case of myofibroma encasing the ulnar nerve on the medial aspect of the left arm with motor and sensory deficit secondary to compression. Initially, the tumour appeared to be a benign peripheral nerve sheath tumour based on preoperative imaging, with clinical examination positive for left hand clawing and a positive Wartenberg's and Froment's sign. However, intraoperative dissection demonstrated that the mass did not originate from the ulnar nerve proper, lowering suspicion for a peripheral nerve sheath tumour. Histopathological analysis showed spindle cell neoplasm, consistent with myofibroma. The patient underwent hand occupational therapy subsequently, with improvement of grip strength from 5 lb to 12 lb by 4 months postoperatively and resolution of clawing of the hand postoperatively. We discuss differentiating features for this rare occurrence of solitary adult myofibroma, where the final diagnosis was only made after formal histopathological analysis.

Prospective outcome analysis of ulnar tunnel syndrome: Comparing traumatic versus non-traumatic etiologies.

BACKGROUND: Ulnar tunnel syndrome (UTS) is relatively uncommon compared to the carpal tunnel or cubital tunnel syndromes. Few reports dedicated to the functional outcomes after surgical intervention of the UTS exist. Herein we compare the outcomes of patients with UTS of different etiologies. METHODS: Patients diagnosed with UTS between 2016 and 2020 were recruited. Ulnar tunnel release was performed in all patients, along with other necessary osteosynthesis or reconstructive procedures in the traumatic group. Patients were followed-up every six months post-operatively. Outcomes measured include: objective evaluations, subjective questionnaires, records of clinical signs, and grading of the British Medical Research Council scale for intrinsic muscle strength. RESULTS: 21 patients were recruited, and favorable results were noted in all of them after surgery. Traumatic UTS patients had a worse initial presentation than the non-traumatic cases, but had a greater improvement after surgery and yielded outcomes comparable with those of the patients without trauma. Patients with aberrant muscles in their wrists had better outcomes in some objective measurements than those without aberrant muscles. CONCLUSIONS: Ulnar tunnel release improves the outcome of patients regardless of the etiology, especially in patients with trauma-induced UTS. Thus, a proper diagnosis of the UTS should be alerted in all patients encountering paresthesia in the ulnar digits, ulnar-sided pain, weakness of grip strength, or intrinsic weakness to ensure good outcomes.

Factors influencing return to work after surgery for ulnar nerve compression at the elbow.

Ulnar nerve compression at the elbow (UNE) frequently affects people of working age. Surgically treated patients may not immediately return to work (RTW) postoperatively. In 2008, the Swedish Social Insurance Agency reformed the national insurance policy. We aimed to examine RTW postoperatively for UNE, variations among surgical methods, and potential risk factors for prolonged RTW (sick leave > 6 weeks). Surgically treated cases of UNE (n = 635) from two time periods (2004-2008 and 2009-2014) and two healthcare regions (Southern and South-eastern) were studied retrospectively regarding age, sex, comorbidities, occupation, type of surgery and time to RTW. A sub-analysis of the exact number of weeks before RTW (n = 201) revealed longer RTW for unemployed cases compared to employed cases. Prolonged RTW was seen among younger, manual workers and after transposition or revision surgery. Prolonged RTW was approximately four times more likely after transposition than after simple decompression. Comparisons before and after 2008 showed occupational differences and differences in RTW, where cases operated before 2008 more often had permanent sickness benefit, but the reform of the social insurance system did not seem to influence RTW. In conclusion, unemployment, younger age at surgery, manual labour, transposition, and revision surgery were related to prolonged RTW.

Psychometric Properties of the Patient-Reported Outcome Measures for People With Ulnar Nerve Entrapment at the Elbow: A Systematic Review.

OBJECTIVE: The objective of this study was to systematically review, critically appraise, and synthesize evidence on the measurement properties of patient-reported outcome measures (PROMs) for people with ulnar nerve entrapment at the elbow (UNE). METHODS: CINAHL, MEDLINE, Embase, and Scopus were searched for studies reporting on the psychometric properties of the PROMs used to assess pain, disability, and quality of life of people with UNE. Relevant data were extracted based on the Consensus-Based Standards for the Selection of Health Measurement Instruments 2018 checklist. Two authors independently rated the quality and risk of bias of the studies. A qualitative synthesis was performed according to the Consensus-Based Standards for the Selection of Health Measurement Instruments guidelines. The results were categorized based on the identified PROMs, and all the psychometric properties were summarized and presented. RESULTS: Eight included studies had a quality score of very good or higher. Among all the included PROMs, the Patient-Rated Ulnar Nerve Evaluation (PRUNE) was comprehensively evaluated in 4 studies and had high reliability, appropriate correlation to the physical component summary score of the 36-Item Short-Form Health Survey (r = -0.68), excellent content (cognitive interviews), structural (factor analysis) and discriminative validities, and high responsiveness. The Disabilities of the Arm, Shoulder and Hand Questionnaire was assessed in 5 studies and had appropriate properties, showing a high correlation with the 8-Item Short-Form Health Survey (r = 0.77) and PRUNE (r = 0.75) and moderate responsiveness. CONCLUSIONS: The PRUNE was the most specific to UNE, had the most supporting studies and evidence of excellent reliability, validity, and responsiveness and therefore was the preferred PROM. The Disabilities of the Arm, Shoulder and Hand Questionnaire demonstrated more limited validation across 5 studies and had moderate responsiveness. Information on other included PROMs was limited in terms of psychometric properties. IMPACT: This study provides insight into which PROM is potentially more suitable for measuring outcomes related to UNE.

Characteristics of surgically treated Guyon canal syndrome: A multicenter retrospective study.

Guyon canal (GC) syndrome is a rare peripheral neuropathy involving the distal part of the ulnar nerve. Several causes are associated with GC syndrome, including anatomic variations, space-occupying tumors, and trauma. Because of disease rarity, the only reported studies of GC syndrome are case series with small sample size. We conducted a multicenter study to identify the basic characteristics of patients with surgically treated GC syndrome and the risk factors for the disease. This retrospective multicenter study was conducted between January 2001 and December 2020. We screened 70 patients who underwent GC release surgery by seven hand surgeons at six institutes. A total of 56 patients were included in this study, including 38 patients (67.9%) who underwent isolated GC decompression and 18 (32.1%) who underwent combined peripheral nerve decompression. The mean patient age was 48.4 years (range: 20-89 years), and 40 patients (71.4%) were male. The average preoperative symptom duration was 18.5 months, and most patients were office workers. Ultrasound was positive for GC syndrome in 7/10 patients evaluated, CT in 2/5, MRI in 17/23, and electrodiagnostic studies in 35/44. The most common cause of GC syndrome was tumor (n = 23), followed by idiopathic (n = 17), trauma (n = 12), anatomic variants (n = 3), and inflammation (n = 3). In conclusion, most patients with GC syndrome in this study were male and had symptoms in one wrist. The most common cause of GC syndrome in this study was a tumor, including a ganglion cyst. Level of Evidence: Level IV case series.

Predictive Factors Associated with the Need for Simultaneous Carpal Tunnel and Ulnar Nerve at the Elbow Releases.

INTRODUCTION: Carpal tunnel syndrome and ulnar nerve compression at the elbow (e.g., cubital tunnel syndrome) are the most common upper extremity compressive neuropa- thies treated by hand surgeons. The aim of this study was to determine demographic factors and comorbidities that can help predict those patients most likely to undergo concurrent release of both the carpal tunnel and ulnar nerve at the elbow. We hypothesized that certain comorbidities, such as diabetes, would be associated with an increased risk for the necessity of concomitant procedures. METHODS: Using Truven Marketscan® database, all patients who underwent carpal tunnel release were identified from 2010 to 2017 using Current Procedural Terminology (CPT) codes. Patients were only included if they had continuous enrollment in the database for 12 months preoperatively. Preoperative comorbidities and concurrent procedures were collected us- ing CPT and ICD-9 and 10 codes. Patients who underwent simultaneous carpal tunnel and ulnar nerve at the elbow release on the same day were compared to those patients who underwent carpal tunnel release alone. Additionally, patients who underwent either procedure initially and then went on to have the other procedure at a later date were compared. Univariate analysis and binomial logistic regression were performed to assess the contribution of patient demographics and comorbidities on the necessity of simultaneous release. RESULTS: 259,574 patients underwent carpal tunnel release surgery and were included in the study. 24,401 (7.9%) of pa- tients also underwent simultaneous ulnar nerve release at the elbow on the same day. Significant risk factors associated with the need for simultaneous release, were male gender [(Odds Ratio (OR): 2.05, Confidence Interval (CI): 2.00-2.11, p < 0.001)], chronic pain (OR: 1.78, CI: 1.68-1.87, p < 0.001), diabetes (OR: 1.29, CI: 1.25-1.33, p < 0.001), history of al- coholism (OR: 1.23, CI: 1.10-1.38, p < 0.001), chronic renal disease (OR: 1.26, CI: 1.18-1.34, p < 0.001), tobacco use (OR: 1.49, CI: 1.42-1.56, p < 0.001), and patients with congestive heart failure (OR: 1.26, CI: 1.17-1.35, p < 0.001). Patients with consumer driven health plans and high deductible health plans (HDHP) were 1.5 times more likely to have simultane- ous release compared to those with comprehensive plans (OR: 1.46, CI: 1.37-1.56, p < 0.001; OR: 1.45, CI: 1.34-1.57, p < 0.001; respectively). For necessity of subsequent carpal or ulnar nerve release after either primary procedure, patients with a minimum of 3 years enrollment in the database were analyzed. Of the 113,505 patients who underwent initial carpal tunnel release, 1,746 (1.5%) went on to undergo release of the ulnar nerve at the elbow. Of the 12,673 patients who had initial ulnar nerve releases at the elbow, 721 (5.7%) required additional release of the carpal tunnel. CONCLUSION: Identification of patient demographic factors and comorbidities that can help predict the likelihood of si- multaneous release of both the carpal tunnel and ulnar nerve at the elbow can help direct management of these patients. Combining the two procedures can help save resources, minimize patient burden, and help reduce excess health care utilization.

Surgically Treated Carpal Tunnel Syndrome and Ulnar Nerve Entrapment at the Elbow in Different Occupations and their Effect on Surgical Outcome.

OBJECTIVE: We investigated whether certain occupations were over-represented among surgically treated carpal tunnel syndrome and ulnar entrapment at the elbow, and if manual occupation affected surgical outcome. METHODS: We included 9030 patients operated for CTS and 1269 for UNE registered in the Swedish National Quality Register for Hand Surgery (HAKIR) 2010-2016. Occupational data was retrieved from Statistics Sweden. Outcome was assessed using the QuickDASH questionnaire. RESULTS: In patients operated for CTS, there were more assistant nurses, attendants/care providers/personal assistants, nannies/student assistants, carpenters/bricklayers/construction workers, cleaners, nurses, and vehicle mechanics than in the general population. In the UNE population, assistant nurses and attendants/care providers/personal assistants were over-represented. Manual workers with CTS scored the preoperative QuickDASH higher than non-manual workers. CONCLUSIONS: Manual workers are overrepresented among surgically treated CTS and UNE. Manual workers with CTS have more symptoms preoperatively than non-manual workers.

Neurolymphomatosis of the Ulnar Nerve Presenting as Cubital Tunnel Syndrome: A Case Report.

Lymphoma is a malignant tumour of the lymphatic system. Neurolymphomatosis occurs when lymphoma cells invade the peripheral nervous system (PNS). Neurolymphomatosis has been reported involving the sciatic nerve, nerve roots and within the axilla and the upper arm. It can cause nerve dysfunction depending on the involved nerve. Neurolymphomatosis involving the ulnar nerve is rare. We report a patient with neurolymphomatosis of the ulnar nerve around the elbow that presented with features of cubital tunnel syndrome. A high index of suspicion is necessary in patients with cubital tunnel syndrome that present with uncommon symptoms such as sudden onset, rapid progression and/or severe pain. Level of Evidence: Level V (Therapeutic).

Diagnosis of ulnar nerve entrapment anterior to the medial epicondyle by ultrasound elastography and diffusion tensor imaging with fiber tractography: a case report.

Ulnar/cubital tunnel syndrome is the second most common compressive neuropathy of the upper limb. Permanent location of the ulnar nerve anterior to the medial epicondyle is extremely rare, with only five cases reported in the literature. Using ultrasound elastography and diffusion tensor imaging with fiber tractography, we diagnosed a case in which ulnar nerve entrapment was associated with anterior nerve location. Surgical release confirmed the diagnosis and the patient was symptom free 3 months after surgery.

Ulnar nerve dislocation in ulnar nerve entrapment at the elbow. Influence on surgical outcome.

Our aim was to assess the incidence of symptomatic ulnar nerve dislocation and its influence on surgical outcome after primary and revision surgeries in ulnar nerve entrapment at the elbow (ulnar neuropathy at the elbow (UNE) or cubital tunnel syndrome). The influence of pre- or intra-operative ulnar nerve dislocation on postoperative outcome was assessed in 548 surgically treated cases (548 nerves) from two hand surgery departments reporting to the Swedish National Quality Registry for Hand Surgery, using QuickDASH, a patient-reported outcome measure (PROM), before surgery and at 3 and 12 months postoperatively, and a doctor-reported outcome measure (DROM), grading as "cured-improved "or "unchanged-worsened," at a median follow-up of 3.0 months [IQR, 1.5-6.0]. 109 of the 548 cases (20%) showed documented pre- or intra-operative ulnar nerve dislocation; more often found at revision (35/75, 47%) than at primary surgery (74/473, 16%) (p < 0.0001). Cases with dislocation presented higher QuickDASH scores at 12 months (p = 0.026). A linear regression model, adjusted for age and gender, predicted higher QuickDASH scores at 12 months postoperatively for cases with dislocation (unstandardized B 11.3 [95% CI 0.4-22.2], p = 0.043). DROM grading as unchanged-worsened at a median 3 months predicted worse QuickDASH scores (p < 0.0001) than in cured-improved cases at 3 (unstandardized B, 18.4 [95% CI 9.4-27.3]) and 12 months (unstandardized B, 18.1 [9.1-27.0]). Primary surgeries had better DROM grading than revision surgeries (p = 0.033; cured-improved, 75% and 63%, respectively), but QuickDASH scores did not differ. Presence of a clinically relevant ulnar nerve dislocation resulted in worse outcome, perhaps due to more extensive surgery with transposition. Nerve dislocation needs attention when treating UNE patients.

A comparative study using electromyography to assess hand exercises for rehabilitation after ulnar nerve decompression.

Ulnar nerve (UN) entrapment is a common peripheral neuropathy and can lead to dysfunction of both sensory and motor function of the hand. Surgical release is the mainstay of treatment, but post-operative rehabilitation of UN innervated intrinsic muscles is lacking evidence. This cohort study utilized surface electromyography (EMG) and assessed the activation of UN innervated intrinsic and extrinsic hand muscles during four exercises in healthy participants. Exercises included rotating baoding balls, squeezing a stress ball or grip device every second, and repetitive finger abduction against a rubber band. Normalized percent activation of each muscle was calculated for each exercise. It was demonstrated that rubber band resistance (RBR) finger abduction showed significantly increased activation in both intrinsic muscles tested, while minimizing activation of the one tested UN innervated extrinsic muscle. Thus, to best target the intrinsic hand muscles without fatiguing extrinsic muscles, the inexpensive and practical RBR exercise is beneficial in post-UN release rehabilitation.

Dynamic Evaluation of Intraneural Microvascularity of the Ulnar Nerve Using Contrast-Enhanced Ultrasonography in Patients With Cubital Tunnel Syndrome.

PURPOSE: The purpose of this study was to compare the intraneural microvascular patterns of the ulnar nerve at 2 elbow flexion angles in asymptomatic volunteers and patients with cubital tunnel syndrome (CuTS) and to evaluate the effects of surgery on the microvascular pattern in patients with CuTS by using contrast-enhanced ultrasonography (CEUS). METHODS: This study included 10 elbows in 10 asymptomatic volunteers (control group) and 10 elbows in 10 patients with CuTS who underwent anterior subcutaneous transposition of the ulnar nerve (CuTS group). The CuTS group underwent clinical and electrophysiologic examinations and CEUS before surgery and at 1, 2, and 3 months after surgery. The intraneural enhancement pattern was calculated as an area under the curve (AUC) value in the entrapment site of the ulnar nerve within the cubital tunnel and in the area 1 cm proximal to the site (proximal site) at elbow flexion angles of 20° and 110°. RESULTS: Serial electrophysiologic examinations showed improvements at 1, 2, and 3 months after surgery compared with before surgery. In the control group, the AUC values of the central part of the cubital tunnel and proximal sites showed no substantial changes with the increase in elbow flexion. In the CuTS group, the AUC in the proximal site at 110° of elbow flexion was decreased compared with that at 20° of flexion before surgery. The AUC values for both the entrapment and proximal sites at 20° and 110° of elbow flexion were the most increased at 2 months after surgery compared with before surgery. CONCLUSIONS: Increased elbow flexion in patients with CuTS influences the intraneural blood flow of the ulnar nerve. Surgery for CuTS alters the intraneural blood flow. CLINICAL RELEVANCE: Quantitative evaluation of the intraneural blood flow of the ulnar nerve using CEUS may be a new supplementary diagnostic tool for CuTS and an indicator for the evaluation of postoperative recovery from nerve damage.

Possible points of compression of the ulnar nerve: Tricks and traps that await clinicians from an anatomical point of view.

The ulnar nerve can be subject to numerous types of compression. The most common are cubital tunnel and ulnar tunnel syndromes, but there are many others with more uncommon etiologies. The existence of additional communicating branches, median nerve involvement, various types of injuries, and unusual anatomical variations can be a challenge for both diagnosis and treatment. This review presents a comprehensive depiction of ulnar nerve entrapment syndromes with particular reference to their anatomical background, risk factors, and clinical evaluation. Even common disorders can result from atypical morphological changes. It is important to be familiar with them as it is a key ability in daily medical practice.