black place; bruise/Vaccination site discoloration; pain got worse; spot in the outside of thighs that hurts/pain in my legs; thigh muscles got tight; spasms in thigh muscles; can't take walks with my dogs; arthritis; lost balance; numbness in thumbs; possible blocked artery being pinched in neck area; muscle aches/muscle problems; Patient also mentioned to be tired; This spontaneous case was reported by a consumer and describes the occurrence of VACCINATION SITE DISCOLOURATION (black place), CONTUSION (bruise/Vaccination site discoloration), PAIN (pain got worse), PAIN IN EXTREMITY (spot in the outside of thighs that hurts/pain in my legs) and MUSCLE TIGHTNESS (thigh muscles got tight) in a 74-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 002B21A and 037B21A) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concurrent medical conditions included Arthritis since September 2020.   On 09-Mar-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 06-Apr-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to 1 dosage form. On an unknown date, the patient experienced VACCINATION SITE DISCOLOURATION (black place), CONTUSION (bruise/Vaccination site discoloration), PAIN (pain got worse), PAIN IN EXTREMITY (spot in the outside of thighs that hurts/pain in my legs), MUSCLE TIGHTNESS (thigh muscles got tight), MUSCLE SPASMS (spasms in thigh muscles), GAIT DISTURBANCE (can't take walks with my dogs), ARTHRITIS (arthritis), BALANCE DISORDER (lost balance), HYPOAESTHESIA (numbness in thumbs), NECK PAIN (possible blocked artery being pinched in neck area), MYALGIA (muscle aches/muscle problems) and FATIGUE (Patient also mentioned to be tired). The patient was treated with PARACETAMOL (TYLENOL) for Adverse event, at an unspecified dose and frequency and CYCLOBENZAPRINE HYDROCHLORIDE (FLEXERIL [CYCLOBENZAPRINE HYDROCHLORIDE]) for Adverse event, at an unspecified dose and frequency. At the time of the report, VACCINATION SITE DISCOLOURATION (black place) and CONTUSION (bruise/Vaccination site discoloration) had resolved, PAIN (pain got worse) and MYALGIA (muscle aches/muscle problems) had not resolved and PAIN IN EXTREMITY (spot in the outside of thighs that hurts/pain in my legs), MUSCLE TIGHTNESS (thigh muscles got tight), MUSCLE SPASMS (spasms in thigh muscles), GAIT DISTURBANCE (can't take walks with my dogs), ARTHRITIS (arthritis), BALANCE DISORDER (lost balance), HYPOAESTHESIA (numbness in thumbs), NECK PAIN (possible blocked artery being pinched in neck area) and FATIGUE (Patient also mentioned to be tired) outcome was unknown.        For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   Patient developed a black place where the shot was injected. Patient said it was not a bruise because it was color black and when resolved it was not yellow but the  HCP said it was a bruise. It appeared 3-4 days after vaccination, and was pinkish/reddish before that.  Patient had muscle aches before the vaccine and went to HCP in Sep 2020.  After the second dose, the pain got worse.  Patient also reported having a spot in the outside of thighs that hurts.  In June, patient reported going to ER.  Patient also mentioned being tired, unable to take walks with her dogs and that  her muscles would tighten up and have spams if  she stood for 5-10 minutes. After picking something up patient lost balance. Patient also experienced thumb numbness and possible blocked artery being pinched in neck area, which was suggested by HCP.  X-ray studies were done as well as bloodwork with unspecified results.