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can be corrected over a short time frame with altered positioning to relieve stress on the lumbar spine. A few sessions of physical therapy can help implement these changes and teach the patient a basic stretching and strengthening program, and 12-week program of therapy has been shown to reduce pain during the second half of pregnancy [37]. Rest plays a role, but can often be counterproductive, leading to more stiffening of muscles and joints.
ACOG recommends the use of low-heeled shoes with arch supports, using lum- bar support when sitting, placement of a board between the box spring and mattress for if the bed is soft, squatting to use the knees when bending to pick up heavy objects, sleeping on the side with a pillow between the knees for additional support, and the use of heat, ice, or massage to relieve painful areas [38].
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Discussion
It is well established that the hormone relaxin peaks during the first trimester of preg- nancy and helps to widen the pubic symphysis and both sacroiliac joints in prepara- tion for delivery [39]. It is not well established, however, whether this hormonal effect leads directly to pelvic pain or whether additional biomechanical, metabolic, genetic, or degenerative factors play separate roles. In reality, pregnancy-related pel- vic girdle pain (PPGP) is likely caused by a combination of all these and other factors that affect women during and after pregnancy [40]. There is no consensus as to the constellation of symptoms with which women present, though it is generally accepted that sharp, stabbing, dull, or shooting pain posteriorly in the SI joints or anteriorly in the pubic symphysis – or both – is usually the primary complaint.
Groin pain, on the other hand, can come from the hip joint itself or surrounding structures, including but not limited to muscles, tendons, connective tissue, and adjacent joints, most notably the pubic symphysis. Evaluation of groin pain begins with ruling out an inguinal or abdominal hernia, low-back disorders, bone infection such as osteomyelitis, bone tumors, urinary or gastrointestinal disease, rupture of the pubic symphysis, and round ligament pain [40]. The round ligament attaches to the uterus, and as the fetus grows, stretching of the ligament can cause transient sharp lower abdominal pain that radiates into the groin. It is treated with pelvic tilt- ing [41]. A thorough history of prior malignancy, signs of local or systemic infec- tion, inflammatory arthropathy, previous trauma, or recent weight loss is critical.
Direct examination of the lumbar spine and SI joints and strength, sensory, and reflex testing of the lower limbs help to rule out disc herniation, mechanical low- back pain, or posterior pelvic abnormalities.
The primary differential for groin pain includes muscle or tendon strain, hip flexor bursitis, femoroacetabular impingement with a labral tear, hip joint degenerative changes, hypermobility, rectus abdominis-adductor aponeurosis injury, or pubic sym- physis dysfunction. The pubic symphysis measures 3–6 cm in nonpregnant individu- als and can separate an additional 2–3 cm during pregnancy. Persistent widening over more than 10 cm is called diastasis, though the exact measurements do not correlate to severity of symptoms. Pain from symphyseal separation localizes to the lower abdomen or suprapubic area but can also radiate into the buttocks, down the legs, or into the groin on one or both sides [42]. Women often complain of pain on weight- bearing, going up and down stairs, and turning in bed. They often wake up in the middle of the night. There is conflicting literature on the incidence of pubic symphysis separation causing pain, but the mainstay of diagnosis is palpation. Deep pressure over the pubic symphysis may evoke local discomfort or cause referral. A step-off may also be felt. Women may also have pain with sit-ups and activation of the adduc- tors, which attach just adjacent to the symphysis. X-rays are not necessary in making the diagnosis, though with pain recalcitrant to conservative management, imaging, especially after delivery of the child, may be warranted to differentiate between degenerative changes, osteitis pubis, diastasis, or inflammatory arthropathy.
Treatment for women with pubic symphyseal pain includes a pelvic belt or gir- dle, activity modification, strengthening of the hip abductors and adductors to better support the pelvis, sleeping in the lateral decubitus position, graded exercise pro- gram, and corticosteroid injections into the joint [43].
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In the absence of recent trauma or specific injury, muscle or tendon strain is unlikely. Hip flexor bursitis is also less common in pregnant females. In those with a history of hip problems or those who have new-onset groin pain with positive labral signs, it is possible and likely that the hip joint is the culprit. Femoroacetabular impingement occurs when the femoral head-neck junction consistently comes in contact with the acetabulum, due to an osseous abnormality on either the femur or pelvis. Overuse and repeated hip flexion and adduction, such as when playing soc- cer and hockey, can lead to tearing of the labrum, a cartilaginous structure that adds depth and cushioning to the joint. Pregnancy can exacerbate symptoms, and mater- nal positioning during delivery can lead to new tearing [44].
Evaluation of the hip involves checking flexion, internal and external rotation, and abduction and adduction of the joint. Impingement testing is performed by flex- ing the hip to 90° than internally rotating and adducting the leg across midline, compressing the femoral head-neck junction against the acetabulum. Reproduction of pain is suggestive of FAI. The scour test is performed by flexing the hip to 90°
and then directing a vertical force down the femur, simultaneously rotating or
“scouring” the joint through its 360° of circular motion. Reproduction of familiar pain or a catch is positive for a likely labral tear. Pain with a straight leg raise at 20°
of hip flexion may also indicate hip joint pathology.
Diagnosis of impingement and labral pathology is confirmed with MRI arthro- gram of the hip [44]. The contrast injection allows for visualization of the labrum, which is not always delineated clearly without dye. Contrast media has not been studied in pregnant women, but given its potential risk as evidenced by laboratory and animal studies, it is best to avoid arthograms and intravenous contrast unless the benefits outweigh the risks [36]. In the case of possible hip labral tears, the woman can be treated based on clinical features, reserving advanced imaging for after labor and delivery. Instead of MRI, patients in extreme pain can undergo a diagnostic and therapeutic injection of anesthetic and corticosteroid into the femoroacetabular joint.
If the patient feels better after the joint is numbed, it is a positive test for an intra- articular pain generator. Manual therapy to relax surrounding soft tissue and physical therapy for hip and abdominal strengthening and stability are also conservative mea- sures used to avoid more aggressive studies and management. MRI without contrast has been shown to be safe, as detailed above, so if osteonecrosis of the femoral head [45] or other more significant bony disease is suspected, MRI may be warranted.
Given all of the biomechanical changes associated with pregnancy, muscles may be activated differently and lead to trigger points in the peripelvic region. Psoas trigger points can mimic impingement, as passive flexion of the hip contracts already contracted muscle, reproducing pain with very specific referral patterns in the groin and down the front of the thigh. Release of these trigger points with dry needling or via manual therapy can provide immediate relief.
Finally, as women gain weight and the uterus compresses the abdomen, the lateral femoral cutaneous nerve, which runs below the inguinal ligament and into the thigh, can be compressed, a condition known as meralgia paresthetica. Women complain of paresthesias into the upper to mid-anterolateral thigh, and there is decreased sensation to light touch in the nerve’s distribution. This condition is exacerbated in the third
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