Ulnar Nerve Neuropathy After Surgery for Intraarticular Distal Humerus Fractures: An Analysis of 116 Patients

PURPOSE

To identify the incidence and the factors associated with a postoperative ulnar nerve neuropathy in patients who had undergone open reduction and internal fixation for intraarticular distal humerus fractures.

METHODS

We retrospectively reviewed 116 patients who had undergone surgery between January 2011 and December 2020. Age, sex, BMI, mechanism of injury, open or closed fracture, operation time, tourniquet time, and nerve injury at the final examination were collected from medical charts. We essentially used the paratricipital approach. In cases in which the reduction of intraarticular bone fragments was difficult, olecranon osteotomy was used. Ulnar nerve function was graded according to a modified system of McGowan. We conducted logistic regression analysis to investigate factors of neuropathy using items identified as statistically significant in univariate analysis as explanatory variables.

RESULTS

Thirty-four patients (29.3%) had persistent neuropathy at the final follow-up. In the modified McGowan classification, 28 patients had grade 1 and 6 patients had grade 2 neuropathy. Olecranon osteotomy emerged as a distinct explanatory variable for the prophylaxis of ulnar nerve neuropathy in the multivariate analysis (odds ratio, 0.30; 95% confidence interval, 0.12-0.73). Anterior transposition, however, was not a statistically significant factor (odds ratio, 1.91; 95% confidence interval, 0.81-4.56).

CONCLUSIONS

Olecranon osteotomy was the only independent factor associated with preventing the occurrence of ulnar nerve neuropathy. Ulnar nerve transposition might not be associated with prevention of ulnar nerve neuropathy.

TYPE OF STUDY/LEVEL OF EVIDENCE

Prognostic IV.

Supercharged End-to-Side Nerve Transfer for Ulnar Neuropathy: Redefining Nomenclature and Recommendations for Standardisation of Surgical Technique Description

Supercharged end-to-side (SETS) nerve transfers have been described as a treatment option for ulnar neuropathy, however, there is inconsistency in the nomenclature used to describe the microsurgical technique. The purpose of this article is to systematically review the available literature on the SETS nerve transfer technique and to provide an overview of the technical variations to facilitate standardisation of surgical method. A literature review was performed through PubMed, MEDLINE, and Ovid databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that reported surgical technique of anterior interosseous nerve (AIN) to ulnar nerve SETS transfer were included. Studies were excluded when not referencing SETS/reverse end-to-side (RETS) nerve transfers, studies referencing nerve transfers other than AIN to motor fascicle bundle of the ulnar nerve (MUN), animal studies, and studies not reporting technique. Of the 168 studies found, 14 articles were included. In five articles, distal visualisation of the MUN in Guyon's canal was specifically cited. In the four studies that commented on donor preparation, sharp neurectomy proximal to the AIN branching point was undertaken. Recipient preparation was commented on in seven of the included studies. Two studies referred to an epineurial window only while five specifically recommended a perineurial window. Coaptation site was specified in four studies and all studies used sutures for coaptation, with four articles stipulating that 9-0 nylon was used. Additionally, fibrin glue was used in conjunction with suture technique in four studies. Consistency in nomenclature used to describe SETS microsurgical technique is needed before case series measuring outcome can be reliably interpreted. This review allowed for the development of suggestions for standardisation of nomenclature and minimal reporting requirements when describing SETS technique. Standardisation of technique will allow for reproducibility and facilitate future evaluations of outcome in prospective randomised control trials.

Iatrogenic Ulnar Nerve Neuropathy Following Reverse Total Shoulder Arthroplasty: Electrodiagnostic Findings in 18 Patients

Background A reverse total shoulder arthroplasty (RTSA) is often recommended for rotator cuff pathology and may be associated with a myriad of complications, including prosthetic instability, infection, humeral problems, and glenoid loosening. Neurological injuries following an RTSA are infrequent and are usually related to brachial plexus or proximal nerve injury in the affected arm. Iatrogenic ulnar nerve neuropathy is exceedingly rare. Aims This study describes the clinical and electrodiagnostic (EDX) features of 18 patients with ulnar nerve neuropathy complicating RTSA. Materials and methods All patients underwent EDX studies, and 14 had an ultrasound (US) study. Results All patients complained of numbness, tingling, hyperalgesia, and/or allodynia in the distribution of the ulnar nerve. Eight (44%) patients reported hand weakness, and one (6%) noted wasting of the intrinsic hand muscles. Decreased pinprick sensation in the ulnar nerve distribution was detected in all patients. Seventeen (94%) patients had weakness of the ulnar nerve-innervated intrinsic hand muscles. All patients had focal slowing of the motor conduction of the ulnar nerve across the elbow. Sensory potentials were either absent or of a low amplitude over the digital and/or dorsal cutaneous branch of the ulnar nerve in all patients. Twelve (86%) patients showed an increase in the cross-sectional area (CSA) of the ulnar nerve at the elbow; six (43%) had a hypoechoic ulnar nerve. Ulnar nerve neuropathy was confirmed at the elbow in all 18 patients. Of the 14 (78%) patients who underwent surgical intervention for ulnar nerve neuropathy following an RTSA, only four had complete symptom resolution. Conclusions Surgeons should be cognizant of ulnar nerve neuropathy as a potential complication of an RTSA and take precautions to avoid damage to the ulnar nerve intraoperatively. EDX and US studies should be performed to confirm and assess the site and severity of the injury.

Peripheral Nerve Stimulator for Pain After Surgery for Ulnar Neuropathy at the Elbow

Neuropathy secondary to ulnar nerve entrapment is a painful condition that often persists following surgical decompression. We present the case of a 43-year-old female with Ehlers-Danlos syndrome and left ulnar neuritis refractory to surgical management. Peripheral nerve stimulation of the ulnar nerve proximal to the elbow resulted in a significant reduction in pain and improvement in disability post-implantation. This case suggests that peripheral nerve stimulation is a promising minimally invasive technique that should be considered for treating non-operative upper extremity neuropathic pain.

Peripheral Nerve Compression Syndromes in Children

Nontraumatic neuropathies of the upper limb are rare in children. In this paper, we present the latest updates in this field and also critically review the diagnosis and treatment of nerve compression syndromes in children. This review describes the most common manifestations including idiopathic carpal tunnel syndrome (CTS), CTS occurring as a component of lysosomal storage diseases (mucopolysaccharidosis) and hereditary neuropathies, ulnar nerve neuropathy, and atraumatic radial nerve neuropathies.