Comparison of electrodiagnostic findings in acute traumatic versus chronic non-traumatic ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: A common concept is that traumatic nerve injuries are more likely axonal, and that compressive neuropathies are more likely demyelinating. The purpose of this study was to compare traumatic versus non-traumatic ulnar neuropathy at the elbow (UNE) to look for electrodiagnostic differences between the two groups. METHODS: A retrospective 3 year review of UNE patients at two academic health science centers was conducted. Patients were grouped into acute traumatic UNE versus chronic non-traumatic UNE based on clinical history. Electrodiagnostic measurements were compared between the two groups. RESULTS: There were 50 subjects with acute traumatic UNE and 41 with chronic non-traumatic UNE. Mean age and sex distribution were similar but those with traumatic UNE had a 7 month duration of symptoms, while those with chronic UNE had 29 month duration (p < .001). All electrodiagnostic measurements were similar between the two groups including compound muscle action potential amplitudes, motor conduction velocities, frequency of conduction block, sensory nerve studies, and needle electromyography. DISCUSSION: We did not find a difference between the two groups. One should not make inferences regarding acuity or etiology based on electrodiagnostic features alone.

Diagnostic efficiency of conventional ultrasound, shear wave elastography, and superb microvascular imaging in evaluating ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: The current diagnosis of ulnar neuropathy at the elbow (UNE) relies mainly on the clinical presentation and nerve electrodiagnostic (EDX) testing, which can be uncomfortable and yield false negatives. The aim of this study was to investigate the diagnostic value of conventional ultrasound, shear wave elastography (SWE), and superb microvascular imaging (SMI) in diagnosing UNE. METHODS: We enrolled 40 patients (48 elbows) with UNE and 48 healthy volunteers (48 elbows). The patients were categorized as having mild, moderate or severe UNE based on the findings of EDX testing. The cross-sectional area (CSA) was measured using conventional ultrasound. Ulnar nerve (UN) shear wave velocity (SWV) and SMI were performed in a longitudinal plane. RESULTS: Based on the EDX findings, UNE severity was graded as mild in 4, moderate in 10, and severe in 34. The patient group showed increased ulnar nerve CSA and stiffness at the site of maximal enlargement (CSA mean at the site of max enlargement [CSAmax] and SWV mean at the site of max enlargement [SWVmax]), ulnar nerve CSA ratio, and stiffness ratio (elbow-to-upper arm), compared with the control group (p < .001). Furthermore, the severe UNE group showed higher ulnar nerve CSAmax and SWVmax compared with the mild and moderate UNE groups (p < .001). The cutoff values for diagnosis of UNE were 9.5 mm2 for CSAmax, 3.06 m/s for SWVmax, 2.00 for CSA ratio, 1.36 for stiffness ratio, and grade 1 for SMI. DISCUSSION: Our findings suggest that SWE and SMI are valuable diagnostic tools for the diagnosis and assessment of severity of UNE.

Bony encasement of the ulnar nerve secondary to heterotopic ossification of the elbow: an evaluation of long-term outcomes.

BACKGROUND: Ulnar neuropathy at the elbow caused by heterotopic ossification (HO) is a rare condition. This retrospective study aims to report on 32 consecutive cases of ulnar nerve encasement caused by elbow HO and evaluate long-term outcomes of operative management and a standardized postoperative rehabilitation regimen. METHODS: A retrospective case series was conducted on 32 elbows (27 patients) that underwent operative management of bony ulnar nerve encasement. All procedures were performed in the inpatient setting at an Academic Level 1 Trauma Center from September 1999 to July 2021 by one of 3 fellowship-trained shoulder and elbow. Postoperatively, all patients received formal physical therapy, HO prophylaxis (30 received indomethacin, 2 received radiation), and a structured continuous passive motion machine regimen. Patient demographics, age, gender, type of injury, history of tobacco use, and medical comorbidities were obtained to include in the analysis. Long-term follow-up examinations were performed to evaluate elbow flexion-extension arc of motion, Mayo Elbow Performance Score, and visual analog scale pain scores. RESULTS: Thirty-two elbows with complete bony ulnar nerve encasement secondary to HO were identified (14 from burns, 15 from trauma, 3 closed head injuries). Following surgery, the mean flexion-extension arc of motion improved significantly, increasing from 21° to 100° at long-term follow-up (average 8.7 years, range 2-17 years), with statistically significant improvements in preoperative vs. long-term postoperative elbow extension (P < .001), flexion (P < .001), and total arc of motion (P < .001). There was a statistically significant improvement in pre- vs. postprocedure ulnar nerve function, as demonstrated by a decrease in average McGowan grade (1.2-0.7; P = .002). Additionally, 63% of patients with preoperative ulnar neuropathy symptoms (20/32) had either complete resolution or subjective improvement after surgery. The mean time from injury to surgery was 518 days (range 65-943 days). Age, gender, time to surgery, and medical comorbidities were not associated with outcomes. The complication rate was 9% (3/32). Patients had an average flexion-extension arc of motion of 97° and average Mayo Elbow Performance Score of 80 ("good") at long-term follow-up. CONCLUSIONS: The combination of operative management, postoperative HO prophylaxis, and a regimented rehabilitation program has proven to be a durable solution for treating and ensuring good long-term functional outcomes for patients with elbow HO and bony ulnar nerve encasement. This treatment approach leads to superior range of motion, improved or resolved ulnar neuropathy, and good to excellent long-term functional outcomes.

Clinical and neurophysiological recovery of ulnar nerve conduction block at the elbow.

INTRODUCTION/AIMS: An important mechanism of peripheral nerve motor and sensory dysfunction is conduction block (CB). However, recovery from mechanically induced CB has been rarely studied in humans. The aim of this study was to describe clinical, electrodiagnostic (EDx), and ultrasonographic (US) characteristics of CB recovery in ulnar neuropathy at the elbow (UNE). METHODS: We recruited a group of consecutive patients presenting to our EDx laboratory with UNE and >50% motor CB. Patients' histories were obtained and neurologic, EDx, and US examinations were repeated every 1-3 mo for at least 12 mo. RESULTS: We studied 10 patients (5 men), with a mean age of 63 y (range, 51-81 y). In all affected arms CB was localized to the retrocondylar groove. Following conservative management, myometrically measured index finger abduction improved from a median of 49% to 100% relative to the contralateral index finger, and ulnar nerve CB decreased from a median of 74% to 6%. Most of the improvement took place within 8 mo of symptom onset, and 6 mo after receiving treatment instructions. Mean motor nerve conduction velocity improved from 15 to 27 m/s in the most affected 2-cm ulnar nerve segment. DISCUSSION: The resolution of CB after typical chronic compression may take longer than after acute compression. This should be considered by clinicians when estimating prognosis for discussions with patients.

Cubital Tunnel Syndrome: Does a Consensus Exist for Diagnosis?

PURPOSE: Cubital tunnel syndrome (CuTS) is the second most common compressive neuropathy of the upper extremity. We aimed to determine a consensus among experts using the Delphi method for clinical criteria that could be validated further for the diagnosis of CuTS. METHODS: The Delphi method was used for establishing a consensus among a group of expert panelists, comprising 12 hand and upper-extremity surgeons, who ranked the diagnostic clinical importance of 55 items related to CuTS on a scale from 1 (least important) to 10 (most important). The average and SDs of each item were calculated, and Cronbach α was used to assess homogeneity among the panelist-ranked items. RESULTS: All panelists answered the 55-item questionnaire. A Cronbach α value of 0.963 was obtained on the first iteration. The top criteria that were considered most clinically relevant to the diagnosis of CuTS among the group were determined based on the most highly ranked and correlated items among the expert panelist group. The criteria based on which there was agreement were as follows: (1) paresthesias in ulnar nerve distribution, (2) symptoms precipitated by increased elbow flexion/positive elbow flexion tests, (3) positive Tinel sign at the medial elbow, (4) atrophy/weakness/ late findings (eg, claw hand of the ring/small finger and Wartenberg or Froment sign) of ulnar nerve-innervated muscles of the hand, (5) loss of two-point discrimination in ulnar nerve distribution, and (6) similar symptoms on the involved side after successful treatment on the contralateral side. CONCLUSIONS: Our study demonstrated a consensus among an expert panelist group of hand and upper-extremity surgeons on potential diagnostic criteria for CuTS. This consensus on diagnostic criteria may help clinicians readily diagnose CuTS in a standardized form; however, further weighting and validation are necessary prior to the development of a formal diagnostic scale. CLINICAL RELEVANCE: This study is the first step in producing a consensus on how to diagnose CuTS.

A complete analysis of the surgical treatment for cubital tunnel syndrome: an umbrella review.

BACKGROUND: Numerous original studies have been presented regarding various surgical treatments for cubital tunnel syndrome (CubTS). The results of these analyses regarding the different surgical treatments for CubTS frequently differ and, in some cases, contradict each other, creating confusion. Therefore, our umbrella review aimed to summarize the evidence from meta-analyses and systematic reviews regarding the surgical treatments of CubTS, and along with the new, more detailed outcomes, provide an evidence-based tool for surgeons performing these procedures. MATERIALS AND METHODS: To perform this umbrella review, a systematic search was conducted for meta-analyses investigating CubTS in PubMed, Scopus, Embase, Web of Science, Google Scholar, Cochrane Library, BIOSIS, and EBSCO medical databases. RESULTS: Detailed comparison of surgical outcomes, such as clinical improvement, complications, or reoperation rates, of different treatment methods for CubTS was performed. New risk ratios in all categories were established based on all of the primary studies available in the literature. DISCUSSION: The goal of the present umbrella review was to gather and summarize all data about the surgical treatments for CubTS in the available literature and provide new outcomes and an evidence-based tool for surgeons performing these procedures. Each comparison of the surgical techniques has been discussed, and the present study's results were compared with the outcomes of the previous studies.

Modified paratricipital approach without mobilization of the ulnar nerve prevents postoperative ulnar neuropathy in distal humerus fractures.

BACKGROUND: In distal humerus fracture surgery, postoperative ulnar neuropathy is a common complication. The present study assessed the utility of the modified paratricipital approach for preventing ulnar neuropathy. This approach preserved the continuity of the attachment of the triceps with the ulnar nerve and allowed anterior subluxation of the ulnar nerve onto the hardware to be avoided. METHODS: From December 2018 to March 2020, 13 patients who underwent surgery for distal humerus fracture through the modified paratricipital approach at our hospital were prospectively enrolled in the study. Ulnar neuropathy, Mayo Elbow Performance Score (MEPS), and Range of motion (ROM) were evaluated. RESULTS: No postoperative ulnar neuropathy was observed. At the final follow-up, the mean Mayo Elbow Performance score was 97.7 (range, 85-100). The mean arc motion was 132.7° (range, 115°-145°) with a mean flexion contracture of 4.2° (range, 0°-10°) and mean flexion of 136.2° (range, 120°-145°). Hardware breakage leading to a loss of reduction occurred in one case, but the other fractures united. CONCLUSIONS: Our results demonstrated the effectiveness of the modified paratricipital approach for preventing postoperative ulnar neuropathy. The modified paratricipital approach is a safe and reliable method of performing distal humerus fracture surgery.

The hand diagram: A novel outcome measure following supercharged end-to-side anterior interosseous nerve to ulnar nerve transfer in severe compressive ulnar neuropathy.

BACKGROUND: With advances in the surgical management for severe ulnar neuropathy with the introduction of the super charged-end-to-side (SETS) anterior interosseous nerve (AIN) to ulnar nerve transfer, a simple and reliable outcome measure is required. There is currently not "one" standardized outcome measure used to represent and compare results. PURPOSE: To present the abduction hand diagram as a "novel", reproducible, and simple outcome measure for patients with severe ulnar neuropathy. STUDY DESIGN: Retrospective case series. METHODS: Nine patients with severe entrapment/compressive ulnar neuropathy at the elbow were reviewed. Clinical parameters included preoperative and postoperative abduction tracings, Medical Research Grade (MRC) muscle strength, key pinch strength, Disability of the Hand Arm and Shoulder (DASH) score, and crossed finger test. Electrodiagnostic data included change in compound muscle action potentials (CMAP) amplitude of the first dorsal interosseous (FDI), and abductor digiti minimi (ADM). Summary statistics were used for demographic and clinical data. RESULTS: Average follow-up was 22.8 ± 9.3 months. At 18-months of follow up, 44% had ADM MRC grade 3 strength or higher, mean key pinch strength improved to 72 ± 19.3%, and mean DASH was 33 ± 28.7. There was a mean increase of 16.7 ± 9.1 mm and 31.5 ± 12 mm in total and summed hand abduction tracing measurements respectively. CONCLUSIONS: Hand abduction tracings are a quantitative outcome measure to follow recovery over time for intrinsic hand function and can be used in patients with severe ulnar neuropathy following surgical intervention.

A Tardy Ulnar Palsy with an Anomalous Course of Ulnar Nerve.

Variations are inherent feature of the intricate brachial plexus. They can be at the level of origin, the course, or the innervation pattern of each peripheral nerve. Knowledge of the various described variations can be worthwhile during the routine hand surgery procedures. We present a case of an elderly patient with anomalous intramuscular course of the ulnar nerve presenting with ulnar neuropathy at the elbow. Level of Evidence: IV.

Evidence-based guideline: Neuromuscular ultrasound for the diagnosis of ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: The purpose of this literature review is to develop an evidence-based guideline for the use of neuromuscular ultrasound in the diagnosis of ulnar neuropathy at the elbow (UNE). The proposed research question was: "In patients with suspected UNE, does ulnar nerve enlargement as measured with ultrasound accurately identify those patients with UNE?" METHODS: A systematic review and meta-analysis was performed, and studies were classified according to American Academy of Neurology criteria for rating articles for diagnostic accuracy. RESULTS: Based on Class I evidence in four studies, it is probable that neuromuscular ultrasound measurement of the ulnar nerve at the elbow, either of diameter or cross-sectional area (CSA), is accurate for the diagnosis of UNE. RECOMMENDATION: For patients with symptoms and signs suggestive of ulnar neuropathy, clinicians should offer ultrasonographic measurement of ulnar nerve cross-sectional area or diameter to confirm the diagnosis and localize the site of compression (Level B).

Cutaneous silent period in ulnar neuropathy at the elbow.

INTRODUCTION/AIMS: The cutaneous silent period (CSP) reflects the function of A-delta sensory fibers. There are few studies on CSP in nerve entrapment syndromes. This study aims to evaluate the neurophysiological abnormalities of small-diameter sensory fibers in ulnar neuropathy at the elbow (UNE) by means of CSP. METHODS: We consecutively evaluated UNE patients at one electrodiagnostic laboratory. The CSP was obtained upon stimulating the fifth (D5) and third digits, recording from the first dorsal interosseous (FDI) and abductor pollicis brevis (APB) muscles. RESULTS: We enrolled 37 UNE patients (mean age 55.4 ± 11.2 y) and 30 controls (mean age 51.2 ± 11.1 y). The combinations of the D5-APB and D5-FDI mean onset latencies of CSP were significantly more prolonged in patients (83.7 ± 6.8 and 84.5 ± 8 ms, respectively) than in controls (78.2 ± 8.1 and 79.4 ± 7.6 ms, respectively). The D5-FDI duration of CSP was shorter in patients (52.2 ± 8.3 ms) than in controls (55.8 ± 7 ms). The mean of the onset latencies of D5-FDI and D5-APB was related to the clinical severity (P = .013 and .0025, respectively). D5-APB and D5-FDI onset latencies were more prolonged and the duration was shorter in the UNE group with absent ulnar sensory nerve action potentials (SNAPs) and axonal motor damage than in patients with preserved SNAPs and with demyelinating damage. DISCUSSION: CSP was able to demonstrate abnormalities of small-diameter myelinated sensory fibers. This damage was directly related to UNE severity and to axonal damage of motor fibers. Absence of a sensory large-diameter fiber response did not exclude preserved residual small fiber conduction.

Risk factors of asymptomatic reduction of motor conduction velocity of the ulnar nerve across the elbow.

INTRODUCTION: The aim of the study was to check the risk factors for subjects with motor conduction velocity (MCV) reduction of the ulnar nerve across the elbow without symptoms/signs of ulnar neuropathy at the elbow (UNE) using a database of a previous multicenter case-control study on UNE patients. METHODS: From the previous database, we extracted all asymptomatic UNE (A-UNE) and matched for age and sex with a control and UNE groups with a ratio of 1:2. Anthropometric factors were measured and all participants filled in a questionnaire on demographic, lifestyle factors, and medical history. One-sample proportion test and univariate and multivariate logistic regression analyses were performed. RESULTS: We enrolled 64 A-UNE, 124 UNE, and 124 controls (mean age 53 years). There were more males with A-UNE than females (74.2%). The predominantly or exclusively concerned side of A-UNE was the right. Logistic regression showed that A-UNE was associated with diabetes (OR = 2.99, 95% CI = 1.21-7.39) and width of cubital groove (CGW) (OR = 0.89, 95%  CI = 0.81-0.97). DISCUSSION: Risk factors for A-UNE are different from UNE. The prevalence of right side in A-UNE was not due to particular elbow postures. Diabetes is a risk factor, probably because MCV reduction of the ulnar nerve across the elbow was an early manifestation of asymptomatic polyneuropathy in diabetes. A-UNE is associated with narrow CGW as already demonstrated in UNE, even if the OR was higher in UNE than in A-UNE. Only future longitudinal studies will be able to check whether the A-UNE subjects develop symptoms and signs of true mononeuropathy with time.

Effect of Perineural Dextrose Injection on Ulnar Neuropathy at the Elbow: A Randomized, Controlled, Double-Blind Study.

OBJECTIVE: To compare perineural dextrose injection efficacy in the treatment of ulnar neuropathy at the elbow with a control group. DESIGN: Prospective double-blind randomized control study. SETTING: Training and research hospital. PARTICIPANTS: The study was completed with 40 patients with ulnar neuropathy at the elbow. INTERVENTION: Normal saline (0.9% sodium chloride) was injected in patients in the control group (n=20; mean age=38.1±10.7 years; median duration of symptoms=4.5 months), and 5% dextrose was injected in patients in the dextrose group (n=20; mean age=43.6±13.5 years; median duration of symptoms=5 months), perineurally under ultrasound guidance twice at 2-week intervals. Ultrasound-guided perineural injection of 1 cc each was administered into the ulnar nerve, 2 cm and 4 cm distal to the medial epicondyle, at the level of the medial epicondyle, and 2 cm and 4 cm proximal to the medial epicondyle. The amount of total fluid injected was 5 cc. MAIN OUTCOME MEASURE(S): At baseline and weeks 2, 4, and 12, the patients were evaluated with the Visual Analog Scale for pain and the Disabilities of the Arm Shoulder and Hand questionnaire for disability. Electrophysiological evaluation was performed with ulnar nerve conduction studies, and the ulnar nerve cross-sectional area was measured on ultrasonography. RESULTS: The improvements in pain, disability, ulnar motor nerve velocity, and ulnar nerve cross-sectional area in the dextrose group were superior to those in the control group, especially at weeks 4 and 12 (P<.001, using independent samples t tests). CONCLUSION: Perineural 5% dextrose may be an effective alternative therapy for those with ulnar neuropathy at the elbow for up to the 12th week.

Reliability and validity of the modified McGowan grade in patients with cubital tunnel syndrome.

INTRODUCTION: This study aimed to assess the reliability and validity of the modified McGowan grading system and to determine its ability to distinguish the severity of cubital tunnel syndrome (CuTS) between the different grades. MATERIALS AND METHODS: We prospectively enrolled 39 consecutive patients with CuTS from March 2018 to December 2020. Inter- and intra-observer reliability was assessed by two orthopaedic surgeons with a minimum 2-week interval using Cohen kappa coefficients. Validity was assessed by Spearman's correlation with objective clinical outcomes (grip strength, Semmes-Weinstein monofilament test [SWMT], static two-point discrimination [2PD], and motor conduction velocity [MCV]). In addition, the relationship between the grading system and patient-reported outcomes (Disabilities of the Arm, Shoulder and Hand score and Boston Questionnaire) was evaluated using Spearman's correlation. The ability to distinguish the severity between the different grades was assessed using the Kruskal-Wallis analysis. RESULTS: The inter-observer kappa value was 0.54 and intra-observer kappa value was 0.59, which imply a moderate reliability. The modified McGowan grade had a moderate correlation with objective clinical outcomes (grip strength [r = - 0.350, p = 0.029], SWMT [r = 0.552, p < 0.001], 2PD [r = 0.456, p = 0.004], and MCV [r = - 0.394, p = 0.021]). However, patient-reported outcomes did not correlate with this grading system. Kruskal-Wallis analysis revealed significant differences between grades in terms of SWMT, 2PD, grip strength, and Boston Questionnaire functional score (p = 0.006, 0.025, 0.014, and 0.043, respectively); however, these differences were statistically significant only for a limited number of parts. CONCLUSIONS: The modified McGowan grade has a moderate inter- and intra-observer reliability. This grading system moderately correlates with objective sensory-motor functions and MCV of patients with CuTS. However, the modified McGowan grade does not reflect the patient's perceived disabilities and has a weakness in distinguishing the severity of patients' conditions among the different grades.

Preventive strategies, exercises and rehabilitation of hand neuropathy in cyclists: A systematic review.

BACKGROUND: Recreation, transportation and sport are the most common uses of bicycles. Unfortunately, repetitive bicycle use can also cause injuries, such as osteoarticular direct and undirect traumatisms and sometimes compression nerve entrapment caused by an extrinsic compressive force. PURPOSE: The aim of the study is to define diagnostic process, preventive strategies, and treatment of ulnar and median neuropathies in cyclists. STUDY DESIGN: Systematic review. METHODS: A search was conducted on PubMed, EMBASE, the Cochrane Library, and Web of Science. Two reviewers independently reviewed articles and came to a consensus about which ones to include. The authors excluded all duplicates, articles involving individuals with other sport-related injuries than cycling, and articles unrelated to peripheral neuropathies. Articles were included if hand palsy was due to peripheral compression of ulnar or median nerve in cyclists. RESULTS: The search identified 15,371 articles with the keywords "Peripheral Nervous System Diseases" OR "neuropathy" OR "ulnar palsy" OR "median palsy" AND "bicycling" OR "bike" OR "bicycle" OR "cyclist". The reviewers analyzed 48 full texts. There were 20 publications that met the criteria and were included in the systematic review. These articles were used to describe the main methods used for diagnosis, prevention and treatment of hand neuropathy of cyclists. CONCLUSION: Despite the range of treatment available for peripheral neuropathies, a unique and common protocol is lacking on this specific topic. For this reason, we delineate a definitive recovery protocol to show the best therapeutic methodologies present in the current literature. Preventive strategies, period of rest since the beginning of the symptomatology, rehabilitation training with muscle strengthening, orthoses at night are the first strategies, but if the symptoms persist, pharmacologic treatment and eventual surgical decompression are sometimes the unique solution.

Comparison of electrodiagnosis, neurosonography and MR neurography in localization of ulnar neuropathy at the elbow.

INTRODUCTION: In patients with ulnar neuropathy at the elbow (UNE) the precise determination of the site of lesion is important for subsequent differential diagnostic considerations and therapeutic management. Due to a paucity of comparable data, to better define the role of different diagnostic tests, we performed the first prospective study comparing the diagnostic accuracy of short segment nerve stimulation, nerve ultrasonography, MR neurography (MRN), and diffusion tensor imaging (DTI) in patients with UNE. METHODS: UNE was clinically diagnosed in 17 patients with 18 affected elbows. For all 18 affected elbows in patients and 20 elbows in 10 healthy volunteers, measurements of all different diagnostic tests were performed at six anatomical positions across the elbow with measuring points from distal (D4) to proximal (P6) in relation to the medial epicondyle (P0). Additional qualitative assessment regarding structural changes of surrounding nerve anatomy was conducted. RESULTS: The difference between affected arms of patients and healthy control arms were most frequently the largest at measure intervals D2 to P0 and P0 to P2 for electrophysiological testing, or measure points P0 and P2 for all other devices, respectively. At both levels P0 and at P2, T2 contrast-to-noise ratio (CNR) of MRN and mean diffusivity (MD) of DTI-based MRN showed best accuracies. DISCUSSION: This study revealed differences in diagnostic performance of tests concerning a specific location of UNE, with better results for T2 contrast to noise ratio (CNR) in MRN and mean diffusivity of DTI-based MRN. Additional testing with MRN and nerve ultrasonography is recommended to uncover anatomical changes.

Diagnosis and Severity Evaluation of Ulnar Neuropathy at the Elbow by Ultrasonography: A Case-Control Study.

Background: Traditional diagnostic techniques such as clinical examination and electrodiagnosis are less sensitive in diagnosing ulnar neuropathy at the elbow (UNE). Ultrasonography (USG) is increasingly being used to diagnose UNE. However, clinical applicability is limited by the lack of uniformity in the previous studies. Therefore, we aimed to study in the Indian patients the diagnostic utility of the ulnar nerve cross-sectional area (CSA) and a novel parameter-entrapment index (EI) in UNE measured by USG and to find if both these parameters correlate with the electrodiagnostic severity. Methods: This retrospective casecontrol study included 28 patients (36 nerves) of UNE and 12 (24 nerves) age- and gender-matched healthy controls. Electrodiagnostic severity was graded using the Padua classification. USG was performed in both groups, and CSA was measured at the medial epicondyle (ME) and 5 cm proximally and distally. EI was calculated by multiplying the ratio of CSA above ME over CSA at ME by 100. Best cutoffs were derived by the receiver operating characteristic curve analysis. Results: UNE group had significantly higher CSA at all three locations and lower EI than the control group. CSA at ME ≥9.7 mm2 and EI ≤61.5 has sensitivity and specificity of 88.9%/87.5% and 72.2%/79.2%, respectively. There was no significant difference in CSA and EI between nonsevere and severe UNE groups. Conclusion: CSA at ME and EI have good sensitivity and specificity in diagnosing UNE. However, they cannot differentiate nonsevere from severe UNE.

Cubital tunnel perfusion in different postures-An anatomical investigation.

INTRODUCTION/AIMS: For cubital tunnel syndrome, the avoidance of predisposing arm positions and the use of elbow splints are common conservative treatment options. The rationale is to prevent excessive stretching and compression of the nerve in the cubital tunnel, as this mechanical stress impedes intraneural perfusion. Data regarding those upper extremity postures to avoid, or whether elbow flexion alone is detrimental, are inconsistent. This study aimed to assess perfusion and size changes of the cubital tunnel during different postures in an experimental cadaver setup. METHODS: Axillary arteries in 30 upper extremities of fresh cadavers were injected with ultrasound contrast agent. High-resolution ultrasound of the cubital tunnel was performed during five different arm postures that gradually increased tension on the ulnar nerve and caused cubital tunnel narrowing. Contrast enhancement within the tunnel was measured to quantify perfusion. Cubital tunnel cross-sectional area was measured to detect compression. RESULTS: Increasing tension significantly reduced perfusion. When isolated, neither shoulder elevation, elbow flexion, pronation, nor extension of wrist and fingers impaired perfusion. However, combining two or more of these postures led to significant decreases. Significant narrowing of the cubital tunnel was seen in full elbow flexion and shoulder elevation. DISCUSSION: Combinations of some upper extremity joint positions reduce nerve perfusion, but isolated elbow flexion does not have a significant impact. We hypothesize that elbow splints alone may not influence cubital tunnel perfusion but may only prevent direct compression of the ulnar nerve. Advising patients about upper extremity postures that should be avoided may be more effective.

Enhancing diagnostic accuracy using a side-to-side cross-sectional area ratio for the diagnosis of unilateral ulnar mononeuropathy at the elbow.

INTRODUCTION: Neuromuscular ultrasonography (NMUS) is a valuable adjunct to electrodiagnostic testing for the diagnosis of entrapment neuropathy. The aim of this study was to determine whether diagnostic accuracy of NMUS could be enhanced in patients with unilateral ulnar mononeuropathy at the elbow (UNE) by utilizing side-to-side ulnar nerve cross-sectional area (CSA) ratios. METHODS: Retrospective case-control analysis of unilateral UNE cases identified cutoff values for elbow segment ulnar nerve maximum CSA (MCSA) of the symptomatic/asymptomatic limb (M ratio), as well as side-to-side ratios comparing MCSA with ipsilateral CSA at the Guyon canal (E/G), middle forearm (E/F), and middle humerus (E/H). Diagnostic accuracy values were calculated. RESULTS: The optimal M-ratio cut-off was 1.22 (sensitivity, 92.9%; specificity, 97.8%; accuracy, 95.4%). Optimal cutoffs for inter-E/G, -E/F, and -E/H ratios were 1.07 (sensitivity, 98%; specificity, 78%; accuracy, 87.7%), 1.11 (sensitivity, 95%; specificity, 80%; accuracy, 87.2%), and 1.18 (sensitivity, 95%; specificity, 93%; accuracy, 94%), respectively. DISCUSSION: The M ratio and inter-E/H ratio exhibited high diagnostic accuracy for unilateral UNE. Prospective studies are needed to compare the accuracy of the new measures with a single MCSA measurement.

Postoperative management and rehabilitation after the supercharged end-to-side anterior interosseous nerve to ulnar motor nerve transfer: A report of 3 cases.

INTRODUCTION: Compressive ulnar neuropathy at the elbow is the second most common compressive neuropathy. Nerve transfers are used for severe ulnar neuropathies as a means of facilitating recovery. Hand therapy and rehabilitation after nerve transfers have not been extensively explored. PURPOSE OF THE STUDY: The aim of this repeated case study was to describe the responses, functional outcome, and neuromuscular health of three participants after the supercharged end-to-side (SETS) anterior interosseous nerve (AIN) to ulnar motor nerve transfer do describe the hand therapy and recovery of 3 cases reflecting different recovery potential mediators, trajectories, and outcomes. STUDY DESIGN: Repeated case study. METHODS: Three participants of similar age (76-80 years) that had severe ulnar neuropathy who underwent surgical treatment including a SETS AIN to ulnar motor nerve surgery were purposively selected from an ongoing clinical trial, based on their response to the surgical and the rehabilitation intervention (large, moderate, and small improvements). Clinical evaluations included measuring range of motion, strength testing, and clinical tests (ie, Egawa's sign) and, subjective assessment of rehabilitation adherence., Quick Disability of Arm, Shoulder and Hand and decomposition-based quantitative electromyography were performed at >23 months to evaluate patients. RESULTS: All the three participants completed the surgical and hand therapy interventions, demonstrating a variable course of recovery and functional outcomes. The Quick Disability of Arm, Shoulder and Hand scores (>23 months) for participants A, B, and C were 68, 30, and 18, respectively. The person with the least improvement had idiopathic Parkinson's disease, dyslipidemia, history of depression, and gout. Comparison across cases suggested that the comorbidities, longer time from neuropathy to the surgical intervention, and psychosocial barriers to exercise and rehabilitation adherence influenced the recovery process. The participants with the best outcomes demonstrated improvements in his lower motor neurons or motor unit counts (109 and 18 motor units in the abductor digiti minimi (ADM) and first dorsal interosseous, respectively) and motor unit stability (39.5% and 37.6% near-fiber jiggle in the ADM and first dorsal interosseous, respectively). The participant with moderate response to the interventions had a motor unit count of 93 for the ADM muscle. We were unable to determine motor unit counts and measurements from the participant with the poorest outcomes due to his physical limitations. CONCLUSIONS: SETS AIN to ulnar motor nerve followed by multimodal hand therapy provides measurable improvements in neurophysiology and function, although engagement in hand therapy and outcomes appear to be mediated by comorbid physical and psychosocial health.