STUDY DESIGN: Resident’s case problem. BACKGROUND: A 21-year-old athletic male college student presented to a direct-access physical therapy clinic with complaints of left calf pain 4 days in duration. After initial examination, a working diagnosis of calf strain was formulated. Three days following initial examination, the patient reported 80% improvement in symptoms and was performing activities of daily living pain free. Four weeks later, the patient returned with complaints of reoccurring calf pain. The patient’s signs, symptoms, and history at subsequent follow-up no longer presented a consistent clinical picture of calf strain; therefore, a D-dimer assay was ordered to rule out a deep vein thrombosis (DVT). DIAGNOSIS: The D-dimer was elevated so the patient was admitted to the hospital and started on low-molecular-weight heparin. A compression ultrasound revealed an extensive left superficial femoral and popliteal DVT in this otherwise healthy athlete. DISCUSSION: Lower extremity DVT is a serious and potentially fatal disorder. Physical therapists need to be diagnostically vigilant for vascular pathology in all patients with extremity pain and swelling. Employing the best current evidenced-based screening tools to rule out vascular pathology, such as deep and superficial vein pathology, should be the goal of every clinician. The Wells score is one such screening tool that has proven to be beneficial in this area. This case report presents a dilemma in diagnosis and illustrates the importance of revisiting differential diagnoses with each patient encounter. Clinicians must consider the possibility of a DVT with every patient seen with posterior leg pain. LEVEL OF EVIDENCE: Diagnosis, level 4.

J Orthop Sports Phys Ther 2011;41(12):942-947. doi:10.2519/jospt.2011.3823

KEY WORDS: clinical prediction rule, D-dimer assay, DVT

Study Design: Resident’s case problem.
Background: A 21-year-old healthy athletic male military cadet with complaint of worsening diffuse left knee pain was evaluated 4 days after onset. The knee pain began 2 hours after completing a long car trip, worsened over the subsequent 3 days, and became almost unbearable during the return trip. The patient reported constant pain, limited knee motion, and difficulty ambulating. In addition, he was unable to perform physical military training or attend academic classes due to the severe left knee pain. Past medical history revealed a mild left lateral calf strain 21⁄2 weeks prior, which completely resolved within 24 hours of onset.
Diagnosis: Our physical examination led us to either monoarticular arthritis, pseudothrombophlebitis (ruptured Baker’s cyst), or a lower leg deep vein thrombosis (DVT) as the cause of knee pain. Diagnostic imaging of this patient revealed a left superficial femoral vein thrombosis and popliteal DVT, with bilateral pulmonary emboli (PE).
Discussion: A systematic differential diagnosis was undertaken to rule out a potentially fatal DVT diagnosis as the cause of knee pain, despite minimal DVT risk factors. The physical therapist in a direct-access setting must ensure timely evaluation and referral of a suspected DVT, even when patient demographics cause the practitioner to question the likelihood of this diagnosis. The physical examination findings, clinical suspicion, and established clinical prediction rules can accurately dictate the appropriate referral action necessary.

J Orthop Sports Phys Ther. 2006;36(9):686-697. doi:10.2519/jospt.2006.2251

Key Words: blood, pulmonary embolism, screening