80-90% reduction in low back pain specifically in the SI joints; This is a spontaneous report from a Pfizer sponsored program. A contactable consumer (patient) reported that, A 71-years-old male patient received bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE; Solution for injection, Batch/Lot number EN6202), dose 2 via an unspecified route of administration, administered in the Arm Left (upper) on 03Mar2021 (at the age of 71-years-old) as a DOSE 2, SINGLE for covid-19 immunisation (To be vaccinated against the virus). Patient's medical history included, Osteoarthritis, Arthritis and insomnia, all from an unknown date and unknown if ongoing. Concomitant medications included ibuprofen (IBUPROFEN), paracetamol (TYLENOL), vitamin b complex one a day 100% multivitamin (B COMPLEX [VITAMIN B COMPLEX]), lisinopril (LISINOPRIL), acetylsalicylic acid (BABY ASPIRIN), pantoprazole sodium (PANTOPRAZOLE SODIUM), all were taken for an unspecified indication and start and stop date were not reported. Patient received bnt162b2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE; Solution for injection, Batch/Lot number EL9269), dose 1 via an unspecified route of administration, on 09Feb2021 (at the age of 71-years-old) as a DOSE 1, SINGLE for covid-19 immunisation. Patient's history of all previous immunization with the Pfizer vaccine considered as suspect (or patient age at first and subsequent immunizations if dates of birth or immunizations are not available) were None. No additional Vaccines was administered on Same Date of the Pfizer Suspect. Other vaccinations within four weeks prior to the first administration date of the suspect vaccine(s) and events following prior vaccinations were None. Patient's Family Medical History Relevant to events was none. The patient experienced 80-90% reduction in low back pain specifically in the SI joints (reduction in inflammation in the lumbo sacral region, therapeutic response unexpected) on 01Apr2021. The first dose was given on 09Feb2021 and the second dose was given on 03Mar2021. Patient stated that, there was a reduction in the general osteo arthritic inflammation. He had not been able to sleep a lot in the past couple of years and then ended up skiing the last 2 weeks of March. His hips usually bother him about 55 minutes into exercise. Patient had a 90-95% reduction of pain in his chronic idiopathic SI joint inflammation. Patient hasn't used a lidocaine patch since the first week of March. This event happened about 2 weeks after the second dose. Patient had the same diet, physical activity, and personal inappropriate behavior so he did not know what else could have caused this other than the vaccine.  The patient later clarifies and confirms that it is an 80-90% reduction in low back pain specifically in the SI joints. He went in for a Lidocaine shot on 30Mar2021. he was getting better before he went skiing in the end of the month. Patient went days without thinking about his back, this has not been a progressive improvement, but it was dramatic and sustained. It was reported that, It used to take the patient half way down the hallway to be able to straightened up his back in the morning but now he pops right out of bed. No relevant Tests were performed. Event Did not require a visit to the Emergency Room or Physician Office. Reporter seriousness for the event was Unspecified. Outcome of the event was not recovered.