Pubic symphysis dysfunction

• Symphysis pubis dysfunction
  • experienced by pregnant women and may start insidiously during pregnancy or abruptly in the peripartum period
  • occurs when the laxity of the ligaments increases. This occurs secondary to hormonal changes during pregnancy e.g. increased levels of relaxin
    • the ligament laxity associated with pregnancy may cause instability and possible separation of the symphyseal joint (i.e. diastasis)
  • degree of separation of separation of the pubic symphysis can be determined in pregnancy with ultrasound or radiologically in the post-partum period
    • separation of up to 9 mm is considered physiological in pregnancy, but pathological if the gap across the pubis is greater than 10 mm (4 mm in non-pregnant females) (1)
    • amount of separation does not always correlate with the severity of symptoms or the degree of disability
    • symphysis pubis dysfunction can occur even without demonstrable separation
  • epidemiology
    • incidence has been quoted at between 1:300 and 1:20000 of pregnancies depending on the diagnostic criteria used
      • however a UK based study found a prevalence of 1/36 women (2). The study authors suggested that this incidence probably reflected their interest in the condition - however they stated that they believed that this figure still represents an underestimate of the problem
      • note though it has been stated that up to 70% of pregnant women experience some form of lower back or pelvic pain in pregnancy, with up to 20% reporting severe pelvic girdle pain (4)
    • more prevalent in Scandinavian countries - this increased prevalence may possibly be due to a genetic link
    • symptoms tend to increase as pregnancy progresses
    • may recur with subsequent pregnancies
    • multiparous women are at increased risk
    • a large study based in Norway found that for the majority the symptoms started in the first trimester and that symptoms persisted after delivery for a mean of 6.5 years (3)
  • clinical features
    • these include pain/discomfort over the symphysis pubis with radiation to the groins and the medial aspects of the thighs, and pain over the sacroiliac joints
      • symptoms appear to vary widely - for some women it may be no more than a discomfort but for others it can become completely debilitating
      • walking is often difficult and a waddling gait is adopted
      • symptoms may be precipitated by any movement that puts stress on the symphysis pubis joint such as standing on one leg during walking, dressing or climbing stairs
    • clinical examination
      • may reveal point tenderness over the symphysis pubis joint and pressure applied over the trochanters reproduces the pain
      • occasionally symphysis oedema may be present
      • a gap at the symphysis pubis may be palpable
      • may exhibit a duck-like waddling gait
  • treatment
    • generally supportive with analgesia and physiotherapy
    • if persistent symptoms and pelvic instability then surgical treatment may be an option - however surgical reduction in pregnancy has a high risk of miscarriage
    • epidural analgesia has been used to treat this condition during pregnancy (1)
    • symptoms tend to get worse as pregnancy progresses and management can be challenging, especially when symptoms are severe or start early in the pregnancy (4)
      • all treatment options are supportive and include lifestyle advice, oral analgesia and physiotherapy-supported exercises and belts

Notes:

• important to distinguish between symphysis pubis dysfunction and rupture of the symphysis pubis joint

Reference:

1. Scicluna JK et al. Int J Obstet Anesth. 2004 Jan;13(1):50-2. Epidural analgesia for acute symphysis pubis dysfunction in the second trimester.
2. Owens K et al. Symphysis pubis dysfunction-a cause of significant obstetric morbidity. Eur J Obstet Gynecol Reprod Biol. 2002 Nov 15;105(2):143-6
3. Maclennan AH, Maclennan AC. Symptom-giving pelvic girdle relaxation of pregnancy, postnatal pelvic joint syndrome and developmental dysplasia of the hip. The Norwegian Association for Women with Pelvic Girdle Relaxation. Acta. Obstet. Gynecol. Scand. 1997;76: 760–764.
4. Munro K, Griffin L, Banerjee A. Ask the expert: Diagnosis and management of complications in pregnancy in primary care BMJ 2023; 382 :p1345 doi:10.1136/bmj.p1345