Anatomy of the interchondral joints and the effects on mobility of ribs.

BACKGROUND: Variations in the anatomy of the anterior rib cage and costal margin have been observed. We sought to evaluate the location of interchondral joints and evaluate their effect on mobility of the rib cage. METHODS: Cadaveric dissections were performed to evaluate the anatomy of the anterior ribs and the composition of the costal margin. Experienced chest wall surgeons and anatomists evaluated this anatomy through a standardized dissection and assessment. The presence of interchondral joints, and morphology and mobility of ribs were quantified. In addition, the movement and interactions of the ribs with upward pressure on the costal margin at the tip of the 10th rib were assessed. RESULTS: Twenty-eight cadavers were evaluated bilaterally. In all patients, the first rib attached to the manubrium, the second rib attached to the sternal/manubrial junction, and ribs 3 to 6 attached directly to the sternum. Interchondral joints were present between ribs 4/5 in 0%, 5/6 in 35%, 6/7 in 96%, and 7/8 in 96%. The eighth/ninth ribs had free tips in 58% and 92%, respectively, and 10th rib was floating in 46%. Upward pressure on the costal margin resulted in compression of the ribs up to, on average, the 5.7 ± 0.6 rib with no compression above this level. This level corresponded to the rib interspace just above the most superior interchondral joint in 98% of evaluation. The transmission of these upward forces demonstrated an articulation of the ribs at the costal cartilage-sternal junction in the lower ribs. CONCLUSION: Bridging interchondral joints are common between ribs 5 to 8 and participate in distributing forces from the costal margin across the chest wall. Upward forces at the costal margin are transmitted across the lower rib cage and result in increased mobility of the lower half of the ribs. The eighth/ninth ribs often have mobile tips, and the 10th is often a floating rib. LEVEL OF EVIDENCE: Diagnostic Test; Level II.

Outcomes of severely injured pregnant trauma patients: a multicenter analysis.

Nearly 10% of pregnant women suffer traumatic injury. Clinical outcomes for pregnant trauma patients (PTPs) with severe injuries have not been well studied. We sought to describe outcomes for PTPs presenting with severe injuries, hypothesizing that PTPs with severe injuries will have higher rates of complications and mortality compared to less injured PTPs. A post-hoc analysis of a multi-institutional retrospective study at 12 Level-I/II trauma centers was performed. Patients were stratified into severely injured (injury severity score [ISS] > 15) and not severely injured (ISS < 15) and compared with bivariate analyses. From 950 patients, 32 (3.4%) had severe injuries. Compared to non-severely injured PTPs, severely injured PTPs were of similar maternal age but had younger gestational age (21 vs 26 weeks, p = 0.009). Penetrating trauma was more common in the severely injured cohort (15.6% vs 1.4%, p < 0.001). The severely injured cohort more often underwent an operation (68.8% vs 3.8%, p < 0.001), including a hysterectomy (6.3% vs 0.3%, p < 0.001). The severely injured group had higher rates of complications (34.4% vs 0.9%, p < 0.001), mortality (15.6% vs 0.1%, p < 0.001), a higher rate of fetal delivery (37.5% vs. 6.0%, p < 0.001) and resuscitative hysterotomy (9.4% vs. 0%, p < 0.001). Only approximately 3% of PTPs were severely injured. However, severely injured PTPs had a nearly 40% rate of fetal delivery as well as increased complications and mortality. This included a resuscitative hysterotomy rate of nearly 10%. Significant vigilance must remain when caring for this population.

Predictors of fetal delivery in pregnant trauma patients: A multicenter study.

BACKGROUND: Pregnant trauma patients (PTPs) undergo observation and fetal monitoring following trauma due to possible fetal delivery (FD) or adverse outcome. There is a paucity of data on PTP outcomes, especially related to risk factors for FD. We aimed to identify predictors of posttraumatic FD in potentially viable pregnancies. METHODS: All PTPs (≥18 years) with ≥24-weeks gestational age were included in this multicenter retrospective study at 12 Level-I and II trauma centers between 2016 and 2021. Pregnant trauma patients who underwent FD ((+) FD) were compared to those who did not deliver ((-) FD) during the index hospitalization. Univariate analyses and multivariable logistic regression were performed to identify predictors of FD. RESULTS: Of 591 PTPs, 63 (10.7%) underwent FD, with 4 (6.3%) maternal deaths. The (+) FD group was similar in maternal age (27 vs. 28 years, p = 0.310) but had older gestational age (37 vs. 30 weeks, p < 0.001) and higher mean injury severity score (7.0 vs. 1.5, p < 0.001) compared with the (-) FD group. The (+) FD group had higher rates of vaginal bleeding (6.3% vs. 1.1%, p = 0.002), uterine contractions (46% vs. 23.5%, p < 0.001), and abnormal fetal heart tracing (54.7% vs. 14.6%, p < 0.001). On multivariate analysis, independent predictors for (+) FD included abdominal injury (odds ratio [OR], 4.07; confidence interval [CI], 1.11-15.02; p = 0.035), gestational age (OR, 1.68 per week ≥24 weeks; CI, 1.44-1.95; p < 0.001), abnormal FHT (OR, 12.72; CI, 5.19-31.17; p < 0.001), and premature rupture of membranes (OR, 35.97; CI, 7.28-177.74; p < 0.001). CONCLUSION: The FD rate was approximately 10% for PTPs with viable fetal gestational age. Independent risk factors for (+) FD included maternal and fetal factors, many of which are available on initial trauma bay evaluation. These risk factors may help predict FD in the trauma setting and shape future guidelines regarding the recommended observation of PTPs. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Outcomes for advanced aged (35 and older) versus younger aged pregnant trauma patients: A multicenter study.

BACKGROUND: Effects of advanced maternal age (AMA) pregnancies (defined as ≥35 years) on pregnant trauma patients (PTPs) are unknown. This study compared AMA versus younger PTPs, hypothesizing AMA PTPs have increased risk of fetal delivery (FD). METHODS: A retrospective (2016-2021) multicenter study included all PTPs. Multivariable logistic regression was used to evaluate risk of FD after trauma. RESULTS: A total of 950 PTPs were included. Both cohorts had similar gestational age and injury severity scores. The AMA group had increased injuries to the pancreas, bladder, and stomach (p < 0.05). There was no difference in rate or associated risk of FD between cohorts (5.3% vs. 11.4%; OR 0.59, CI 0.19-1.88, p > 0.05). CONCLUSION: Compared to their younger counterparts, some intra-abdominal injuries (pancreas, bladder, and stomach) were more common among AMA PTPs. However, there was no difference in rate or associated risk of FD in AMA PTPs, thus they do not require increased observation.