Compression of the median nerve in pregnancy is thought to be due to fluid retention within the carpal tunnel space. We aim to discover the cause of carpal tunnel syndrome (CTS) in pregnancy using high resonance ultrasonography. Methods: This is a cross-sectional study where obstetric patients were screened for CTS and subjected to a non invasive ultrasonic imaging. Results: A total of 63 patients were seen with 25 diagnosed to have CTS (39.7%) and 38 patients had none (60.3%) based on a screening tool. Age ranged from 20-42 years old with the highest range in the 28-30 year old group (34.9%). In patients with CTS, the cross sectional area of the median nerve inside the tunnel was a mean of 0.908 cm² ie larger, while non-CTS patients had a mean of 0.797 cm² inside the tunnel. The transverse carpal ligament (TCL) measured a mean of 0.0988 cm in the CTS group (ie thinner) and 0.1058 cm in the non-CTS group. Median nerve mobility at equal to or less than one tendon width was 80% in pregnant women with CTS and 92.1% for those without. No fluid was present within the carpal tunnel of all patients. The results were statistically not significant. Conclusion: Ultrasonographic evidence in pregnant women with CTS shows a larger median nerve, a more mobile median nerve and a less thick transverse carpal ligament. There is absence of fluid retention and synovitis ruling out extrinsic compression of the median nerve as cause of CTS in pregnancy.

INTRODUCTIONCarpal tunnel syndrome (CTS) is a common pregnancy complication. However, it is often overlooked by medical practitioners and patients alike. This study aimed to describe CTS in relation to pregnancy and assess how significant the disease was among pregnant women.

METHODSIn a prospective cross-sectional study, 333 respondents were randomly selected from among pregnant women attending the primary care maternal health clinic in a university hospital. CTS was diagnosed clinically based on patient history and physical examination. The severity of CTS was assessed using the Boston Carpal Tunnel Questionnaire. Symptomatic respondents were asked whether they had mentioned their problems to doctors and received appropriate treatment.

RESULTS82 (24.6%) pregnant women presented with symptoms of CTS, a majority of whom were ethnic Malays (Malay 87.8%; non-Malay 12.2%). The risk for developing CTS during the third trimester of pregnancy was found to be two-fold among Malay women compared to patients of other ethnicities (odds ratio 2.262; 95% confidence interval 1.10-4.46; p = 0.024). The commonest complaint was daytime numbness (76.8%). The severity of CTS among patients was predominantly mild (80.5%), and the symptoms were severe enough to affect hand function in approximately one-third (34.1%) of the group. However, only 25.6% of symptomatic patients mentioned their problems to their doctors, and of these, 9.5% received treatment.

CONCLUSIONCTS is prevalent in the third trimester of pregnancy, especially among Malay women, in whom the risk of developing the syndrome is two-fold. Yet, this troublesome complication of pregnancy appears to be under-recognised, with most patients not being treated appropriately.

Adolescent ; Adult ; Carpal Tunnel Syndrome ; diagnosis ; epidemiology ; etiology ; pathology ; Cross-Sectional Studies ; Female ; Humans ; Middle Aged ; Pregnancy ; Pregnancy Complications ; diagnosis ; epidemiology ; pathology ; Pregnancy Trimesters ; Risk Factors ; Severity of Illness Index ; Young Adult