Ian R. McPhail

Quadrilateral Space Syndrome: The Mayo Clinic Experience With a New Classification System and Case Series

Quadrilateral space syndrome (QSS) arises from compression or mechanical injury to the axillary nerve or the posterior circumflex humeral artery (PCHA) as they pass through the quadrilateral space (QS). Quadrilateral space syndrome is an uncommon cause of paresthesia and an underdiagnosed cause of digital ischemia in overhead athletes. Quadrilateral space syndrome can present with neurogenic symptoms (pain and weakness) secondary to axillary nerve compression. In addition, repeated abduction and external rotation of the arm is felt to lead to injury of the PCHA within the QSS. This often results in PCHA thrombosis and aneurysm formation, with distal emboli. Because of relative infrequency, QSS is rarely diagnosed on evaluation of athletes with such symptoms. We report on 9 patients who presented at Mayo Clinic with QSS. Differential diagnosis, a new classification system, and the management of QSS are discussed, with a comprehensive literature review. The following search terms were used on PubMed: axillary nerve, posterior circumflex humeral artery, quadrilateral space, and quadrangular space. Articles were selected if they described patients with symptoms from axillary nerve entrapment or PCHA thrombosis, or if related screening or imaging methods were assessed. References available within the obtained articles were also pursued. There was no date or language restriction for article inclusion; 5 studies in languages besides English were reported in German, French, Spanish, Turkish, and Chinese.

Transcutaneous partial pressure of oxygen after surgical wounds

Transcutaneous partial pressure of oxygen (TcPO2) predicts wound healing in critical ischemia. However, no studies have controlled for the effect of wounds on TcPO2. In this study, in 24 hip or knee arthroplasty cases without vascular disease, TcPO2 was measured preoperatively at the incision site, contralaterally, and at a reference site on the chest wall. The measurements were repeated at 2 days and 2 months postoperatively and compared. TcPO2, normal preoperatively, decreased at all sites on the second postoperative day (p < 0.001), with a trend toward a greater decrease at the wound (p 1/4 0.09). All wounds healed, and TcPO2 returned to baseline at all sites 2 months postoperatively. In conclusion, acute surgical wounds are associated with a significant and widespread decrease in cutaneous TcPO2 in the setting of normal arterial perfusion. This decrease is likely multifactorial and deserves further investigation.

Abdominal Aortic Aneurysm and Diastasis Recti

Midline abdominal incisional hernias are common following open repair of abdominal aortic aneurysms. These may be caused by the weakness of connective tissue. This study sought to determine the prevalence of diastasis recti among unoperated Caucasian males with abdominal aortic aneurysm compared to a control group with atherosclerotic lower extremity peripheral arterial disease. Forty-two consecutive white males referred for evaluation of abdominal aortic aneurysm (n = 18) or peripheral arterial disease (n = 24) were examined by a single examiner at the Mayo Clinic. Both groups were similar in terms of age and smoking history, 2 major risk factors for both abdominal aortic aneurysm and peripheral arterial disease. Abdominal aortic aneurysm patients ranged in age from 59 to 89 (mean, 73.2) years. Seventeen of 18 (94.4%) had a history of smoking. Peripheral arterial disease patients ranged in age from 52 to 93 (mean, 70.8) years. Twenty-one of 24 (87.5%) had a history of smoking. Diastasis recti were present in 12 of 18 (66.7%) subjects with abdominal aortic aneurysm versus 4 of 24 (16.7%) subjects with peripheral arterial disease (P = .001, 2-tailed Fisher exact test). Diastasis recti are significantly more common in males with abdominal aortic aneurysm than peripheral arterial disease and may provide an important clue to screen for abdominal aortic aneurysm in those at risk.

Inflammatory Abdominal Aortic Aneurysm A Case Report and Review of Literature

We report a case of an abdominal aortic aneurysm (AAA) that underwent inflammatory transformation which we treated medically with corticosteroids. Medical therapy resulted in resolution of presenting symptoms and observed inflammatory changes. We review the clinical features, associated pathology, diagnostic, and therapeutic options in the management of inflammatory AAA.

Prevalence of Abdominal Wall Hernia in Participants With Abdominal Aortic Aneurysm Versus Peripheral Arterial Disease—A Population-Based Study

Small studies suggest an association between abdominal aortic aneurysms (AAAs) and hernias, possibly related to connective tissue weakness. We evaluated the association between AAA and abdominal wall hernia (AWH), using peripheral arterial disease (PAD) patients as controls, in Olmsted County, Minnesota. In a retrospective cohort study we queried the electronic medical records for the diagnosis of AAA. The resulting data were then queried for prevalence of AWH. The same set of queries was repeated for PAD. Occurrence of AWH in the 2 groups was compared using the chi-square test. Of the 187 151 patient records queried, 939 had AAA and 3465 had PAD. Abdominal wall hernia occurred in 157 (16.7%) patients with AAA and in 343 (9.9%) patients with PAD. Abdominal wall hernia was 1.7 times more prevalent in those with AAA versus PAD (P < .0001). A history of hernia may prompt screening for AAA in some patients.

Retrievable inferior vena cava filters can be placed and removed with a high degree of success: Initial experience.

Evaluate the success rate of retrievable inferior vena cava filter (IVC) removal in a tertiary care practice.

Digital obstructive arterial disease can be detected by laser Doppler measurements with high sensitivity and specificity

OBJECTIVE This study was conducted to determine the sensitivity and specificity of laser Doppler flowmetry (LDF) measurements for digital obstructive arterial disease (DOAD) using angiography as the reference standard and to compare the accuracy of different classical tests used to assess DOAD. Diagnosis of vascular abnormalities at the digital level is challenging. Angiography is the gold standard for assessment of DOAD but is invasive and expensive to perform. METHODS We performed a retrospective analysis of consecutive patients referred at Mayo Clinic (Rochester, Minn) for upper extremity arterial assessment during a 27-month period. Finger-brachial index, skin blood flow (in arbitrary units [a.u.]), and skin temperature (in degrees Celsius) were recorded in each digit on the pulp at baseline and after a thermal challenge test (hand placed in a thermal box at 47.0°C for 15 minutes). Angiogram analysis was blinded and performed by a radiologist using a vascularization scale ranging from 0 (no vessel) to 4 (normal). The receiver operating characteristic curve was used to define a specific cutoff point to detect DOAD. Twenty-two patients had LDF measurements and complete angiograms. RESULTS A total of 185 digits were analyzed because some patients had only analysis of one hand. The best area under the curve (AUC) was 0.98 (range, 0.94-0.99) for postwarming skin blood flow, with a cutoff point of ≤206 a.u. This AUC was statistically different from AUCs of all the other tests (P < .01). Sensitivity and specificity were 93% (95% confidence interval, 85%-97%) and 96% (95% confidence interval, 90%-99%), respectively. CONCLUSIONS LDF combined with a thermal challenge is highly accurate, safe, and noninvasive means to detect DOAD.

Clubbing Due to Peripheral Hypervascularization: Recognition by Contrast-Enhanced, Three-Dimensional Magnetic Resonance Angiography

To the Editor: The magnetic resonance angiogram of the left hand shown by Wiesmann et al1 is an incomplete display of the arteries that is further confounded by venous contamination. From this image, one cannot conclude that “there is no evidence of vasculitis or arterial stenosis or occlusion.” Spatial resolution of a fraction of a millimeter is required to diagnose vasculitis in the hand. …

Embolic Strokes After Peripherally Inserted Central Catheter Placement

Peripherally inserted central catheters (PICCs) have become popular for a range of indications in both inpatient and outpatient settings. Though PICCs are generally safe, they can be associated with a variety of complications. We present here a case with embolic strokes due to inadvertent arterial placement of PICC, an uncommon but potentially life-threatening complication. A high clinical suspicion with critical evaluation of radiographs is indispensable for suspecting misplaced PICCs.

Mediastinal seminoma presenting with superior vena cava syndrome

We present a rare cause of superior vena cava syndrome (SVC) in a previously healthy male aged 31 years. Malignancy was suspected due to unintentional weight loss and childhood exposure to radioactive fallout from a nuclear facility accident. A very large anterior mediastinal mass was identified and demonstrated to be an extragonadal seminoma. Extragonadal germ cell tumours are rare tumours with a high potential for cardiovascular, pulmonary and vascular sequelae. Studies have documented an increased risk of developing seminoma in patients with radioactive exposure. Chemotherapy was initiated, during which the patient experienced progressive and new symptoms, found to be due to extensive thromboembolic disease, which responded well to anticoagulation. Seventy-two months after completing chemotherapy, without need for surgical management, he remains free of the disease.