Lumbrical muscle tear: clinical presentation, imaging findings and outcome.

The incidence of lumbrical muscle tear is increasing due to the popularity of climbing sport. We reviewed data from 60 consecutive patients with a positive lumbrical stress test, including clinical examination, ultrasound and clinical outcomes in all patients, and magnetic resonance imaging in 12 patients. Fifty-seven patients were climbers. Lumbrical muscle tears were graded according to the severity of clinical and imaging findings as Grade I-III injuries. Eighteen patients had Grade I injuries (microtrauma), 32 had Grade II injuries (muscle fibre disruption) and 10 had Grade III injuries (musculotendinous disruption). The treatment consisted of adapted functional therapy. All patients completely recovered and were able to return to climbing. The healing period in Grade III injuries was significantly longer than in the patients with Grade I or II injuries ( p < 0.001). We recommend evaluation of specific clinical and imaging findings to grade the injuries and to determine suitable therapy. LEVEL OF EVIDENCE: IV.

Uncommon lesions in the internal auditory canal (IAC): review of the literature and case report.

BACKGROUND: Despite the relatively frequent occurrence of multiple primary tumors, namely, 10% of intracranial tumors, metastasis is a rare occurrence within the internal auditory canal (IAC) and cerebellopontine angle (CPA). Intracanalicular metastases of adenocarcinoma are documented, but a primary adenocarcinoma remains unreported. We provide a review of uncommon lesions in the IAC and describe to our knowledge the first instance of a primary adenocarcinoma. CASE REPORT: A 60-year-old man presented with nausea and vomiting. Cranial computed tomography scan revealed bilateral nonspecific periventricular and subcortical vascular lesions. He presented 8 months later with left-sided tinnitus, progressive hearing loss, and attacks of vertigo. Magnetic resonance imaging (MRI) showed an extra-axial mass most likely representing a left-sided vestibular schwannoma with characteristic contrast enhancement in the IAC. The follow-up MRI showed an unchanged pattern of contrast enhancement. Due to progressive headaches and dizziness, the patient underwent a left transtemporal craniotomy with subtotal tumor resection. Histological examination revealed blennogenic cylindrical adenocarcinoma. The investigations for the primary tumor site were all negative. The patient's condition deteriorated gradually. MRI showed an increase of the residual tumor and meningeosis carcinomatosa, and cerebrospinal fluid (CSF) examination was positive for tumor cells. The patient was treated with intrathecal chemotherapy. He died of multiple organ failure. DISCUSSION: The discussion focuses on the incidence of extra-axial CPA and IAC lesions with their clinical presentations and their radiological findings. We address the issue of a possible regulation of CPA lesion laterality by asymmetrically expressed genes. In view of the sparse literature on treatment of single intracanalicular metastases, the review is broadened to the current treatment recommendations of single brain metastases. CONCLUSIONS: The differentiation between benign and malign lesions in the CPA and IAC is important, as it requires diverse treatment protocols. For the physician this differentiation represents a clinical and radiological challenge. For the developmental research the left-right asymmetry might be a field of research.