Knee swelled up; knee pain; She feels crippled by the shot. She feels if she takes a step or moves the wrong way like she has ripped out her knee; My arm hurt / arm pain; This case was received via an unknown source (no reference has been entered for a health authority or license partner) on 14-Oct-2021 and was forwarded to Moderna on 14-Oct-2021.     This spontaneous case was reported by a consumer and describes the occurrence of JOINT SWELLING (Knee swelled up), ARTHRALGIA (knee pain) and JOINT INJURY (She feels crippled by the shot. She feels if she takes a step or moves the wrong way like she has ripped out her knee) in a 59-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch no. 021C21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     No Medical History information was reported.   On 07-Jul-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 12-Aug-2021, received dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On an unknown date, the patient experienced JOINT SWELLING (Knee swelled up) (seriousness criterion disability), ARTHRALGIA (knee pain) (seriousness criterion disability), JOINT INJURY (She feels crippled by the shot. She feels if she takes a step or moves the wrong way like she has ripped out her knee) (seriousness criterion disability) and PAIN IN EXTREMITY (My arm hurt / arm pain). The patient was treated with PREDNISONE (oral) for Adverse event, at a dose of 1 dosage form. At the time of the report, JOINT SWELLING (Knee swelled up), ARTHRALGIA (knee pain), JOINT INJURY (She feels crippled by the shot. She feels if she takes a step or moves the wrong way like she has ripped out her knee) and PAIN IN EXTREMITY (My arm hurt / arm pain) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Magnetic resonance imaging: inconclusive (abnormal) Showed "a tiny bit of arthritis in there". On an unknown date, X-ray: inconclusive (Inconclusive) x-rays of her knee which showed no changes and inconclusive (Inconclusive) x-rays of her knee which showed no changes.   The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) was unknown.   Concomitant product use was not provided by the reporter.  It was reported that the patient also received a methyl-prednisone 40mg and lidocaine injection on 24SEP2021. Talked to 2 doctors and has plans to see a 3rd doctor on Monday.  Company Comment: This case concerns a 59-year-old female patient with no relevant medical history, who experienced the unexpected serious events of JOINT SWELLING, ARTHRALGIA and JOINT INJURY. The events occurred approximately 3 weeks after receiving the first dose of Moderna COVID-19 Vaccine. Rechallenge was not applicable. The benefit-risk relationship of mRNA-1273 (Moderna COVID-19 Vaccine) is not affected by this report.   This case was linked to MOD-2021-353003 (Patient Link).; Sender's Comments: This case concerns a 59-year-old female patient with no relevant medical history, who experienced the unexpected serious events of JOINT SWELLING, ARTHRALGIA and JOINT INJURY. The events occurred approximately 3 weeks after receiving the first dose of Moderna COVID-19 Vaccine. Rechallenge was not applicable. The benefit-risk relationship of mRNA-1273 (Moderna COVID-19 Vaccine) is not affected by this report.