Lumbar
lumbar area
Lumbar.
Dorsal
The medical terminology combining form meaning lower back is "lumb/o" or "lumb".
I think you are trying to describe a Lumbar Puncture, which is performed in the lower (lumbar) region of the spine.
"Calf" is the most common designation for a young bovine. However, the animal may be called a bull calf if it is a male or a heifer if it is a female.
Lumb- is the medical terminology combining form meaning lower back.
lumbosacral
What I think you are looking for is "lumbago" which per definition is a symptom of lower back pain that can have numerous causes, it is preffered to use the cause as diagnosis (diagnostic codes) if known. Back pain can be caused by many different things of which one is strain of the lower back muscles. .A strain is caused by a tear/injury to muscles or tendons. There is no word other then strain in english for what you are asking for to my knowledge other than some direct translation to latin that is not used internationally.
Dorsal is the medical term meaning back.
Dorsum is a medical term meaning back. For example the dorsum of the hand is commonly known as the back of the hand.
the lumbar region (lower back)
A strain is a medical term meaning there has been abnormal stretching on a muscle and its tendons. This generally causes a painful contraction of the muscle in an attempt to protect itself from further damage. A lumbar strain is a strain in the lumbar region of the back, specifically, the region of the back from below the ribcage to where the spine attaches to the pelvis. This is a very common cause of back pain.
cervical region: neck Thoracic region: back Lumbar region: lower back sacral region: pelvic girdle Coccyxgeal region: tailbone