Acute handlebar syndrome: Two extremes of a challenging diagnosis

Background:

Ulnar nerve mononeuropathy diagnosis can be challenging depending on where neural lesion is present. Repetitive trauma during cycling is a rare cause of ulnar neuropathy.

Case Description:

We describe two patients who developed the handlebar syndrome, an ulnar nerve palsy at Guyon’s canal after cycling. The first patient had the syndrome after a short-distance ride and she was treated surgically, while the second patient developed the classical syndrome after a long ride and received conservative treatment. Surgical treatment of the first patient led to functional recovery.

Conclusion:

Handlebar syndrome is a neuropathy caused by extrinsic repetitive compression of ulnar nerve at wrist. Increasing incidence of this disease can be expected after increasing popularity of cycling sports. Avoid of repetitive trauma is the main management goal, with surgical treatment reserved for failure of conservative treatment.

Idiopathic Ventral Spinal Cord Herniation: Video Report and Systematic Review

BACKGROUND

Idiopathic ventral spinal cord herniation (ISCH) is a rare disease; however, it is an important differential diagnosis. Its treatment presents some controversies.

CASE DESCRIPTION

We report on a 55-year-old woman who had been presenting with relevant back pain and leg weakness for the past 3 years and urinary incontinence for the past 3 months. Clinical examination disclosed paresis on the right inferior limb and right foot, as well as a T6-level painful hypoesthesia. Magnetic resonance imaging disclosed a T4/T5 ISCH. The patient underwent surgical decompression. During the procedure, we opened the arachnoid and cut the dentate ligaments of the spine, which considerably improved the mobility and safety of the procedure. In the early follow-up, our patient presented a partial improvement regarding the paresis grades and hypoesthesia pain relief on the left side. A video showing the surgical procedure and case evolution is presented. We also assembled literature reviews to compare our case with others. ISCH is becoming a more recognized cause of progressive thoracic myelopathy. However, this condition is still frequently misdiagnosed. Magnetic resonance imaging is the key for diagnosis. The objective of surgical treatment is to prevent myelopathy progression. The technique presented in this report is an appropriate surgical option, once it is a safer way to identify and treat the defect. The neurologic condition usually improves greatly after surgical treatment, especially when the patient presents positive predictive factors.

CONCLUSIONS

ISCH is being more recognized. The technique presented is an appropriate surgical option.

Optimal E2 (reference) electrode placement in fibular motor nerve conduction studies recording from the tibialis anterior muscle

INTRODUCTION

In this study we aimed to determine the contribution of the E2 (reference electrode) to the compound muscle action potential (CMAP) amplitude during fibular motor recording to the tibialis anterior (TA) when E2 is placed over routine referential vs. alternative sites.

METHODS

The CMAP was obtained from 10 healthy subjects, using the active electrode (E1) over sites routinely used as E2 for the TA, whereas the E2 was over the contralateral knee. The same procedure was performed with the E1 over alternative E2 sites.

RESULTS

Significant electrical signal was captured over routine E2 placement sites. Among the tested alternative E2 sites, the ipsilateral patella (especially its medial aspect) was the most electrically silent.

DISCUSSION

Using alternative E2 sites with near isoelectric recordings can optimize near-field potential measurement in the fibular motor recording to the TA and represents a more accurate way of measuring nerve and muscle function. Muscle Nerve 59:249-253, 2019.