Spica MRI is a fast and effective tool to assess morphology after closed reduction for developmental dysplasia of the hip (DDH) without the need for sedation. The multiplanar capabilities allow depiction of coronal and axial reduction of the hips. Due to MRI's inherent ability to delineate soft tissue structures, both intrinsic and extrinsic obstacles to failed reduction may be identified. Technical and interpretative challenges of spica MRI are discussed.

A series of ester homologues 2-5 of the mu receptor nonequilibrium antagonist beta-funaltrexamine (1, beta-FNA) was synthesized. These ligands were of interest in our investigation of the relationship between the structure of the ester function and the ability to irreversibly block mu opioid receptors. While all of the ligands were potent reversible agonists in the guinea pig ileum (GPI) and mouse vas deferens (MVD) preparations, most appeared to behave as irreversible antagonists of morphine. The benzyl 5 and phenethyl 6 esters possessed irreversible mu antagonist potency that was of similar magnitude to that of beta-FNA in the GPI. In the MVD, all esters appeared to irreversibly block the agonist effect of morphine, but none of the compounds irreversibly antagonized [D-Ala2,D-Leu5]enkephalin to a significant degree. [3H]Dihydromorphine displacement studies revealed no relationship between the affinity of the esters 1-6 and the irreversible blockage of mu receptors in the GPI or MVD. Possible reasons for the observed structure-activity relationship are discussed.

Multiligament knee injuries (MLKIs) are debilitating injuries that increasingly occur in young athletes. Return to sport (RTS) has historically been considered unlikely due to the severity of these injuries. Reporting in the literature regarding objective outcomes following MLKI, including RTS, is lacking, as are clear protocols for both rehabilitation progressions and RTS testing. RTS following MLKI is a complex process that requires an extended recovery duration compared to other surgery types. Progressions through postoperative rehabilitation and RTS should be thoughtful, gradual, and criterion based. After effective anatomic reconstruction to restore joint stability, objective measures of recovery including range of motion, strength, movement quality, power, and overall conditioning guide decision-making throughout the recovery process. It is important to frame the recovery process of the athlete in the context of the severity of their injury, as it is typically slower and less linear. Improved reporting on objective outcomes will enhance our understanding of recovery expectations within this population by highlighting persistent deficits that may interfere with a full recovery, including RTS.M ultiligament knee injuries (MLKIs) are defined as a tear of 2 or more of the major knee ligaments, which include the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), and lateral collateral ligament or fibular collateral ligament (FCL). 1,2 These devastating injuries are relatively uncommon, with more recent reports of 0.072 events per 100-patient years within the general population. 1,3,4 MLKIs are often associated with knee dislocation, defined as a rupture of both cruciates with or without additional grade III injury to one of the collaterals. 5 Disruption of the popliteal artery and/or common peroneal nerve (CPN) constitutes a medical emergency that can have devastating consequences if unrecognized. 6 MLKIs are seen more commonly in younger patients, with a mean age of 37 AE 15 years. 7,8 The incidence of knee dislocation has been inversely correlated with age. 7,8 MLKIs are often associated with high-energy trauma such as a motor vehicle accidents or fall from a height; however, nearly 50%, occur through a low-velocity mechanism, most commonly sport. 9,10 Rates of MLKI caused by skiing sports and ball sports are as high as 29.4% and 6.9%, respectively. In the same cohort, motor vehicle accidents only accounted for 19.2% of all injuries. 7 Given the severity of MLKI and the complexity of multiligament knee reconstruction (MLKR), return to sport (RTS) has historically been considered highly unlikely. RTS data have been inconsistent and incomplete, but existing evidence cites a RTS rate of 53%, 11 with competitive athletes having a lower RTS rate of 22%. 11 While surgical proficiency with MLKR has improved, RTS may be hindered by concerns regarding long-term joint health. MLKI patients show high rates of concomitant injury to articular cartilage (28.3%-48%) and men...

A series of 6,14-dideoxynaltrexones that contain different electrophiles in the 6-position were synthesized and evaluated for nonequilibrium opioid antagonist activity in the guinea pig ileum and mouse vas deferens preparations. Members 3-5 of the series possessed irreversible antagonist activity profiles similar to those previously reported for the 14-hydroxy analogues. In contrast, the 14-deoxy-beta-funaltrexamine (14-deoxy-beta-FNA) analogue (6) exhibited a profile of irreversible antagonist activity that differed from that of beta-FNA. It was concluded that the 14-hydroxy group is not essential for irreversible blockage when the electrophile is capable of reacting with a broad spectrum of nucleophiles. However, with a highly selective electrophile such as the fumarate group, the 14-hydroxy function appears to play a role in aligning the molecule to optimize attack by a receptor-based nucleophile.