Bleeding in the pelvis is rare without significant trauma and is usually seen in patients who are taking blood-thinning medications, such as warfarin (Coumadin). In these patients, a rapid-onset sciatica pain can be a sign of bleeding in the back of the pelvis and abdomen that is compressing the spinal nerves as they exit to the lower extremities. Infection of the pelvis is infrequent but can be a complication of conditions such as diverticulosis, Crohn's disease, ulcerative colitis, pelvic inflammatory disease with infection of the Fallopian tubes or uterus, and even appendicitis. Pelvic infection is a serious complication of these conditions and is often associated with fever, lowering of blood pressure, and a life-threatening state.
Since the hip flexors are so easy to overuse and strain, it is important to stretch them before exercise or strenuous activity. Because of their connectedness to other muscle groups in the legs (like the quadriceps), it is important to stretch the muscle group as a whole, not individually. This ensures that the entire area is warmed up and ready for the strain of exercise or activity, not just one or two individual muscles.
The side of the pain on its own doesn’t tell us much, and most of the one-sided sources of pain are viscera that usually cause abdominal pain instead of back pain, or in addition to it. In other words, the only reason to worry about right or left lower back pain is if it is otherwise worrisome: if you have other red flags or significant non-back symptoms. 

If low back pain occurs after a recent injury — such as a car accident, a fall or sports injury — call your primary-care physician immediately. If there are any neurological symptoms, seek medical care immediately. If there are no neurological problems (i.e. numbness, weakness, bowel and bladder dysfunction), the patient may benefit by beginning conservative treatment at home for two to three days. The patient may take anti-inflammatory medications such as aspirin or ibuprofen and restrict strenuous activities for a few days. 

These exercises can be done three to five times per week; be sure to build in a rest day here or there to allow your hip muscles to recover. Working to strengthen your knees and ankles can be done as well to be sure you completely work all muscles groups of your lower extremities. Remember, your ankle and knee muscles help control the position of your hips, just as your hip muscles control the position of your knees and ankles. They all work together in a kinetic chain.
If low back pain occurs after a recent injury — such as a car accident, a fall or sports injury — call your primary-care physician immediately. If there are any neurological symptoms, seek medical care immediately. If there are no neurological problems (i.e. numbness, weakness, bowel and bladder dysfunction), the patient may benefit by beginning conservative treatment at home for two to three days. The patient may take anti-inflammatory medications such as aspirin or ibuprofen and restrict strenuous activities for a few days.
The diagnosis of low back pain involves a review of the history of the illness and underlying medical conditions as well as a physical examination. It is essential that a complete story of the back pain be reviewed including injury history, aggravating and alleviating conditions, associated symptoms (fever, numbness, tingling, incontinence, etc.), as well as the duration and progression of symptoms. Aside from routine abdomen and extremity evaluations, rectal and pelvic examinations may eventually be required as well. Further tests for diagnosis of low back pain can be required including blood and urine tests, plain film X-ray tests, CAT scanning, MRI scanning, bone scanning, and tests of the nerves such as electromyograms (EMG) and nerve conduction velocities (NCV).
AAOS does not endorse any treatments, procedures, products, or physicians referenced herein. This information is provided as an educational service and is not intended to serve as medical advice. Anyone seeking specific orthopaedic advice or assistance should consult his or her orthopaedic surgeon, or locate one in your area through the AAOS Find an Orthopaedist program on this website.
How to do it: Stand with your feet together, holding dumbbells by your sides. Take a wide step out to your right and lower into a side lunge, reaching dumbbells on either side of right leg [as shown]. Bend your left knee and shift your weight into both legs, into a wide squat position, reaching the dumbbells to floor in front of you, then extend your right leg and shift your weight to the left, moving into a side lunge with your left leg.
Low back pain (LBP) is a common disorder involving the muscles, nerves, and bones of the back.[4] Pain can vary from a dull constant ache to a sudden sharp feeling.[4] Low back pain may be classified by duration as acute (pain lasting less than 6 weeks), sub-chronic (6 to 12 weeks), or chronic (more than 12 weeks).[3] The condition may be further classified by the underlying cause as either mechanical, non-mechanical, or referred pain.[5] The symptoms of low back pain usually improve within a few weeks from the time they start, with 40–90% of people completely better by six weeks.[2]
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