The study is designed as a prospective comparative study. All patients will receive prophylactic anticoagulation according to routine hospital protocol after surgery. A bedside ultrasound examination will be performed by a trained anesthesiologist prior to the surgery and then daily beginning on postoperative day 2 until patient discharge.

Recent studies conducted at the emergency department evaluated the usefulness of an abbreviated bedside compression ultrasound test for diagnosis of Deep Venous Thrombosis (DVT) in the proximal region. This abbreviated ultrasound test conducted in the groin and popliteal regions to assess the compressibility of the femoral and popliteal veins required as little as 3.5 min to complete 15 and can be easily mastered by residents with minimum training. These studies showed a promising sensitivity ranging from 70% to 100% and a specificity ranging from 75.9% to 99.6%.

Anesthesiologists are now well-trained in performing ultrasound scans as they perform ultrasound-guided peripheral nerve blocks routinely. Scanning for significant proximal DVT could potentially be anesthesiologists' extended role as they follow up patients who underwent orthopedic surgeries for postoperative pain control as part of the acute pain service.

Inclusion Criteria:

• ASA physical status I-III
• 18-85 years of age, inclusive
• 50-110 kg, inclusive
• 150 cm of height or greater
• Patients who are scheduled to have surgical repair of the fractured hip and those who will have unilateral or bilateral, primary or revision, hip or knee arthroplasty.

Exclusion Criteria:

• The presence of indwelling femoral vascular catheter or dialysis vascular shunts in the operative leg
• An above-knee amputation
• The inability to access all two landmarks (femoral and popliteal veins) for two-point ultrasonography because of the presence of a cast, external fixation apparatus, or other obstacles