Change in cervical length after arrested preterm labor and risk of preterm birth.

OBJECTIVE: To assess the association between preterm birth and cervical length after arrested preterm labor in high-risk pregnant women. METHODS: In this post-hoc analysis of a randomized clinical trial, transvaginal cervical length was measured in women whose contractions had ceased 48 h after admission for threatened preterm labor. At admission, women were defined as having a high risk of preterm birth based on a cervical length of < 15 mm or a cervical length of 15-30 mm with a positive fetal fibronectin test. Logistic regression analysis was used to investigate the association of cervical length measured at least 48 h after admission and of the change in cervical length between admission and at least 48 h later, with preterm birth before 34 weeks' gestation and delivery within 7 days after admission. RESULTS: A total of 164 women were included in the analysis. Women whose cervical length increased between admission for threatened preterm labor and 48 h later (32%; n = 53) were found to have a lower risk of preterm birth before 34 weeks compared with women whose cervical length did not change (adjusted odds ratio (aOR), 0.24 (95% CI, 0.09-0.69)). The risk in women with a decrease in cervical length between the two timepoints was not different from that in women with no change in cervical length (aOR, 1.45 (95% CI, 0.62-3.41)). Moreover, greater absolute cervical length after 48 h was associated with a lower risk of preterm birth before 34 weeks (aOR, 0.90 (95% CI, 0.84-0.96)) and delivery within 7 days after admission (aOR, 0.91 (95% CI, 0.82-1.02)). Sensitivity analysis in women randomized to receive no intervention showed comparable results. CONCLUSION: Our study suggests that the risk of preterm birth before 34 weeks is lower in women whose cervical length increases between admission for threatened preterm labor and at least 48 h later when contractions had ceased compared with women in whom cervical length does not change or decreases. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Optimizing surgery of metaphyseal-diaphyseal fractures of the fifth metatarsal: a cadaveric study on implications of intramedullary screw position, screw parameters and surrounding anatomic structures.

AIMS: Many advocate screw fixation of fractures to the metaphyseal-diaphyseal junction of the fifth metatarsal base, better known as Jones fractures (JF), to facilitate quicker ambulation and return to sport. Maximizing screw parameters based on fifth metatarsal (MT5) anatomy, alongside understanding the anatomic structures compromised by screw insertion, may optimize surgical outcomes. This study aims to (1) correlate the proximity of JF to the peroneus brevis (PB) and plantar fascia (PF) footprints and (2) quantify optimal screw parameters given MT5 anatomy. MATERIALS AND METHODS: 3D CT-scan reconstructions were made of 21 cadaveric MT5s, followed by meticulous mapping of the PB and PF onto the reconstructions. Based on bone length, shape, narrowest intramedullary canal (IMC) diameter, and surrounding anatomy, two traditional debated screw positions were modeled for each reconstruction: (1) an anatomically positioned screw (AP), predicated on maximizing screw length by following the IMC for as long as possible, and (2) a clinically achievable screw (CA), predicated on maximizing screw length without violating the fifth tarso-metatarsal joint or adjacent cuboid bone. Fixation parameters were calculated for all models. RESULTS: The PB and PF extended into the JF site in 29% and 43%, respectively. AP's did not affect PB and PF footprint but required screw entry through the cuboid and fifth tarso-metatarsal joint in all specimens. CA screw entry sites, avoiding the cuboid and fifth tarso-metatarsal joint, partially compromised the PB and PF insertions in 33% and 62% with a median surface loss of 1.6%%(range 0.2-3.2%) and 0.81%%(range 0.05-1.6%), respectively. Mean AP screw length was 64±3.6mm and thread length 49±4.2mm. Mean CA screw length was 48±5.8mm and thread length 28±6.9mm. CONCLUSION: This study underscores the challenges associated with surrounding MT5 anatomy as they relate to optimal JF treatment. Both the extent of JF as well as a clinically achievable positioned screw violate the PB and PF footprints - although the degree to which even partial disruption of these footprints has on outcome remains unclear. To minimize damage to surrounding structures, including the PB and PF footprint, while allowing a screw length approximately two thirds of the metatarsal length, the CA screw position is recommended. This position balances the desire to maximize pull out strength while avoiding cortical penetration or inadvertent fracture site distraction.