The Crossing Motor Ulnar Nerve Branch at Elbow.

BACKGROUND AND OBJECTIVES: Cubital tunnel syndrome is the second most common nerve entrapment, and understanding the anatomy is crucial for the success of the nerve release. During ulnar nerve release for cubital tunnel syndrome, a motor branch is frequently encountered crossing anteriorly over the ulnar nerve from its medial/ulnar side proximally to the lateral/radial side distally. Little has been noted about this crossing branch in the literature. In this anatomic study, we sought to characterize this branch further and discuss its potential significance in cubital tunnel release. METHODS: We performed a cadaveric dissection of 48 elbow specimens as if performing a cubital tunnel release. We assessed for the presence of the crossing motor branch of the ulnar nerve and measured the distance from the medial epicondyle to the branch takeoff and to its target of innervation. RESULTS: Of our 48 specimens, 34 (71%) were noted to have a crossing motor branch at the area of compression by the deep flexor carpi ulnaris muscle fascia (common aponeurosis). On average, the distance from the medial epicondyle to the branch origin from the ulnar nerve was 18.2 mm and to the target muscle innervation was 28.4 mm. CONCLUSION: Identifying this branch is important for performing a cubital tunnel release, and awareness of this anatomy during ulnar nerve decompression procedures may help avoid injury to this motor branch.

Symptomatic Idiopathic Ulnar Nerve Instability in the Elbow Diagnostic Considerations and 1-Year Outcomes After Anterior Transposition of Ulnar Nerve.

BACKGROUND: Symptomatic idiopathic ulnar nerve instability (IUNI) in the elbow is an uncommon condition characterized by symptoms of ulnar neuritis resulting from frictional injury to the ulnar nerve from repetitive subluxation out of the cubital tunnel. This study reports the 1-year clinical outcomes after treatment of IUNI with anterior transposition of the ulnar nerve. METHODS: This is a retrospective case study of five patients. Ulnar nerve instability was diagnosed clinically based on the presence of ulnar neuritis symptoms in combination with a positive "ulnar nerve push past" test. Electromyography (EMG) was performed on all patients. After failure of nonsurgical treatment, five patients underwent anterior subcutaneous transposition of the ulnar nerve at the elbow. Clinical outcome scores and time to resolution of symptoms were recorded at a minimum follow-up of 12 months. RESULTS: The mean age of the patients at the time of surgery was 37.8 years (range: 18 to 57 years). The mean duration of symptoms prior to surgery was 15.7 ± 4.9 months. All five patients reported neuritis symptoms in the distribution of ulnar nerve in the hand and had ulnar nerve instability in the cubital tunnel on clinical examination. All patients were symptom free within 6 months after anterior transposition of the ulnar nerve.

Ultrasound-guided minimally invasive cubital tunnel thread release: An experimental study.

INTRODUCTION: Cubital Tunnel Syndrome is characterized by the compression of the ulnar nerve in the cubital tunnel and can cause restrictions to the activities of daily living. Traditional treatment includes conservative methods and, in more severe cases, different types of surgery. In these cases, common side effects of surgery may limit the clinical success. A new alternative could be a minimally invasive Ultrasound-guided (US-guided) thread release of cubital tunnel retinaculum also known as the Osborne's ligament. The aim of this study was to assess the efficacy and safety of ultrasound-guided thread cubital tunnel release (TCuTR) in an anatomical specimen model. METHODS: In this single-center prospective experimental study, US-guided thread cubital tunnel release (TCuTR) was performed on 11 softly embalmed anatomic specimens. Subsequently, the elbows were dissected to assess the transection of Osborne's ligament and potential damage to adjacent structures. RESULTS: Due to calcification, one specimen was ineligible for the intervention. In all remaining ten interventions, Osborne's ligament (OL) was completely transected, without any damage to the surrounding nerves, blood vessels, tendons, or muscles. CONCLUSION: US-guided decompression has demonstrated a high success rate in transecting Osborne's ligament while averting damage to neighboring structures. This emerging technique appears to present an efficient and secure alternative to existing procedures.

Subcutaneous Anterior Transposition With Modified Procedures to Prevent Recurrence Associated With the Transposed Ulnar Nerve.

Subcutaneous anterior transposition of the ulnar nerve is a common surgical treatment for cubital tunnel syndrome. However, there are surgical failures associated with the new compressive sites at the edge of flexor carpi ulnaris (FCU) and resubluxation posterior to the medial epicondyle of the transposed nerve. To reduce the muscle volume at the edge of FCU, we approach the ulnar nerve by dividing the muscle belly of the FCU humeral heads. This procedure can reduce repeated traction forces on the transposed nerve at the edge of the FCU. To keep the transposed ulnar nerve anteriorly, we use a fat flap including the membranous superficial fascia. This flap can softly stabilize the ulnar nerve and act as a pliable cover to prevent perineural scarring or further constriction around the flap. Ninety-three elbows in 90 patients who had undergone this procedure for cubital tunnel syndrome were evaluated. According to Messina's criteria, the numbers of patients showing excellent, good, fair, and poor recovery were 41 (44%), 47 (51%), 5 (5%), and 0 (0%), respectively. Most patients experience resolution of symptoms and good functional outcomes. None of the patients suffered recurrence, infection, or nerve injury.

Cubital tunnel release with Wide Awake Local Anaesthesia No Tourniquet (WALANT) technique in an outpatient setting is safe and effective.

Ulnar nerve release is often performed under general anaesthesia. Wide Awake Local Anaesthesia No Tourniquet (WALANT) is a new anaesthetic method increasingly used by hand surgeons in an outpatient setting. It has advantages such as the possibility to shift surgical interventions out of the regular surgical theatre settings into an outpatient clinical setting, no risk of complications or side effects resulting from regional and general anesthesia and decreased costs. The use of WALANT has not been investigated extensively in elbow surgery. This study aims to evaluate clinical outcomes after ulnar nerve release under WALANT 27 patients with ulnar nerve release for cubital tunnel syndrome were included. The primary outcome was the presence of (remaining) symptoms after ulnar nerve release. Data was extracted from medical records. 13 out of 27 patients had (mild) remaining symptoms after ulnar nerve release, and 1 complication (superficial wound infection) was seen. Ulnar nerve release under WALANT is safe and effective in patients with primary ulnar nerve entrapment that have failed conservative therapy.

Round table discussion: the management of idiopathic cubital tunnel syndrome.

Idiopathic cubital tunnel syndrome is the second most common neuropathy in the upper limb. Best evidence regarding the surgical management of this condition has evolved from anterior or submuscular transposition as the former reference standard, to in situ simple release. Differences of opinion remain regarding the timing of surgery, type of surgery and adjunctive surgery. Four surgeons with Level 5 expertise were asked to answer specific questions regarding this condition.

The anatomical variations of the cubital tunnel in a South African body donor sample.

PURPOSE: The ulnar nerve (UN) courses through the cubital tunnel, which is a potential site of entrapment. Anatomical variations of the cubital tunnel may contribute towards cubital tunnel syndrome (CuTS), however, these are not well described. The aim was to compare the range of variations and dimensions of the cubital tunnel and the UN between sexes and sides of the body. METHODS: Sixty elbows from 30 embalmed bodies (17 males and 13 females) were dissected. The prevalence of the cubital tunnel retinaculum (CuTR) or anconeus epitrochlearis (AE) forming the roof of the tunnel was determined. The length, width, thickness, and diameter of the cubital tunnel and its roof were measured. The diameter of the UN was measured. RESULTS: The AE was present in 5%, whereas the CuTR was present in the remaining 95% of elbows. The tunnel was 32.1 ± 4.8 mm long, 23.4 ± 14.2 mm wide, 0.18 ± (0.22-0.14) mm thick, and the median diameter was 7.9 ± (9.0-7.1) mm, while the median diameter of the UN was 1.6 ± (1.8-1.3) mm. The AE was thicker than the CuTR (p < 0.001) and the UN was larger in elbows with the AE present (p = 0.002). The tunnel was longer in males (p < 0.001) and wider on the right (p = 0.014). CONCLUSION: The roof of the cubital tunnel was more frequently composed of the CuTR. The cubital tunnel varied in size between sexes and sides. Future research should investigate the effect of the variations in patients with CuTS.

Electrodiagnostic severity does not predict short- to midterm outcomes of cubital tunnel release surgery.

HYPOTHESIS: This study aimed to explore the prognostic value of electrodiagnostic studies (EDS) to clarify their utility in clinical practice prior to cubital tunnel release surgery and to identify patient factors associated with patient-reported functional improvement after surgery. Our hypothesis was that patients with severe preoperative findings on EDS will tend to experience less functional improvement after surgery given the extent of ulnar nerve compressive injury. METHODS: Patients with cubital tunnel syndrome and preoperative electrodiagnostic data treated from 2012 to 2022 with cubital tunnel release were assessed regarding demographic information, preoperative physical examination findings, EDS findings, postoperative complications, and patient-reported outcomes. Short- to midterm quick Disabilities of the Arm, Shoulder, and Hand questionnaire (qDASH) scores were collected for all patients for further evaluation of preoperative EDS data. Patients were grouped into those who had met the minimal clinically important difference (MCID) in delta qDASH at short- to midterm follow-up and those who did not. EDS data included sensory nerve onset latency, peak latency, amplitude, conduction velocity, as well as motor nerve latency, velocity, and amplitude. Electromyographic (EMG) studies were also reviewed, which included data pertaining to fibrillations, presence of abnormal fasciculation, positive sharp waves, variation in insertional activity, motor unit activity, duration of activity, and presence of increasing polymorphisms. RESULTS: Of the 257 patients included, 160 (62.0%) were found to meet the MCID for short- to midterm qDASH scores. There were no significant differences between patients who did or did not meet the MCID regarding baseline demographics, comorbidities, preoperative examination findings, and operative technique. Patients who met MCID tended to have lower complication (3.80% vs. 7.20%, P = .248) and revision (0.60% vs. 4.10%, P = .069) rates, but these findings were not statistically significant. The cubital tunnel severity as determined by the EDS was similar between cohorts (14.1% vs. 14.3%, P = .498). Analysis of EMG testing showed there were no significant differences in preoperative, short- to midterm qDASH, or delta short- to midterm qDASH scores for patients with or without abnormal EMG findings. Multivariate regression suggested that only age (P = .003) was associated with larger delta qDASH scores. CONCLUSION: Patient-reported preoperative disease severity may predict the expected postoperative change in ulnar nerve functional improvement, and EDS may not have prognostic value for patients undergoing cubital tunnel decompression. Therefore, physicians may suggest surgical treatment without positive EDS findings and still expect postoperative improvement in functional outcomes.

State of the art review. Upper extremity revision nerve compression surgery.

Although surgical release of upper extremity nerve compression syndromes is highly effective, persistence or recurrence of symptoms and signs may occur. Thorough investigation is necessary in this situation before treatment is recommended. If the symptoms cannot be explained by other pathology than compression of the affected nerve and if conservative management has not provided improvement, reoperation may be considered. This review provides an overview of the diagnostic and surgical considerations in the revision of carpal tunnel syndrome, cubital tunnel syndrome and thoracic outlet syndrome.Level of evidence: V.

Comparative Analysis of Ultrasound-Assisted Precise Localization vs. Traditional Open Incision in Situ Decompression for the Treatment of Cubital Tunnel Syndrome.

AIM: To retrospectively analyze and compare ultrasound-assisted localization in situ with the traditional, open incision method for treating cubital tunnel syndrome (CuTS). MATERIAL AND METHODS: We retrospectively analyzed 51 patients treated between 2018 and 2022 and categorized them according to treatment method: ultrasound-assisted precise localization in situ decompression (n=21; Cohort 1) and traditional open incision in situ decompression (n=30; Cohort 2). We additionally collected Visual Analogue Scale (VAS) scores, Vancouver Scar Scale (VSS) scores, modified Bishop scores, aesthetic appearance, preoperative Dellon's stage, and analgesics requirements. Additional dependent variables of interest included operation time, hospital stay duration, complications, and reoperation rate. RESULTS: Neither cohort demonstrated significant changes in Dellon's stage, modified Bishop score, or VAS scores between baseline and 6 weeks postoperative. Cohort 1 showed better aesthetics and postoperative VSS and VAS scores than Cohort 1. In addition, Cohort 1 enjoyed a significantly shorter mean operation time and hospital stay. Cohort 1 had 5 (23.80%) complications, including superficial infection (n=1), hematoma (n=1), and incomplete decompression (n=3). Cohort 2 had 9 complications (30.00%), including superficial infection (n=2), hematoma (n=2), and severe scarring (n=5). The partial, incomplete decompression cases in Cohort 1 and the severe scar case in Cohort 2 were treated with reoperation. CONCLUSION: Both procedures effectively treated most cases of CuTS and were associated with good postoperative outcomes. Patients who underwent ultrasound-assisted localization in situ decompression had shorter surgeries and hospital stays, better postoperative aesthetics, better VSS and VAS scores, and required less pain medication during the postoperative period. Traditional open incision in situ produced a more thorough decompression.