O3266: Osteosarcoma Masquerading as Sports-related Injury: A Case Series

Introduction: Although seemingly rare, osteosarcomas account for 3% of all childhood cancers and are the most common type of bone cancer. This malignancy arises from osteoblasts which are most active during growth spurts. Consequently, long bones in adolescents are predominantly affected. Initial symptoms can be vague such as joint pain, swelling, or a limp, and patients often present first to their primary care physician. Therefore, thorough evaluation and appropriate workup on presentation is vital for diagnosis.

Case Description: There were a total of three patients included in this case series. Their histories and clinical courses are outlined below:

Discussion: 1. 17 year-old female wakeboarder with gradual knee and thigh pain for 8 weeks. She reported pain at rest, but not with activity. Exam: no tenderness to palpation or limited range of motion. Weakness and atrophy noted. Outcome: in remission.
2. 17 year-old male theater student with worsening knee and calf pain for 4 weeks after an injury while wearing high heels during dance choreography in a school play. He reported swelling and pain mostly with ambulation. Exam: medial joint line tenderness, mild swelling, limited flexion/extension, + lateral McMurray sign and Apley’s test. Outcome: amputation, no metastasis.
3. 16 year-old female dancer with gradual knee pain and limp for 6 weeks that was worse with bending and stairs, but claimed that it “hurts all the time.” Exam: tenderness to palpation over the lateral joint line and posterior aspect of the knee, limited flexion/extension, + patellar grind, and no palpable mass. Outcome: clinical trials, multiple lung relapses. Passed away 2/12/23 (age 25).

Conclusion: Given that each of these patients presented to a sports medicine clinic (though their true underlying etiology was oncologic), it is important to recognize the nuances of osteosarcoma presentation in an outpatient clinical setting. Many athletes present to their primary care provider for an initial diagnosis and subsequent guidance. A patient’s pain chronicity, location, and age all play a role in determining urgency of further diagnostic workup and subspecialist referral. These patients all had progressively worsening pain lasting more than 4 weeks and experienced pain at rest. Therefore, it is vital to increase awareness of these patterns to not only pediatricians/PCPs, but also orthopedists and non-operative sports medicine physicians.