Return to Play After Surgical Treatment for Acromioclavicular Joint Dislocation: A Systematic Review.

BACKGROUND: Acromioclavicular (AC) joint dislocation is a common clinical problem among young and athletic populations. Surgical management is widely used for high-grade dislocations (Rockwood III-VI) and in high-demand athletes at high risk of recurrence. PURPOSE: To systematically review the evidence in the literature to ascertain the rate and timing of return to play (RTP) and the availability of specific criteria for safe RTP after surgical treatment for AC joint dislocation. STUDY DESIGN: Systematic review; Level of evidence, 4. METHODS: A systematic literature search based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was conducted in the PubMed database. Clinical studies were eligible for inclusion if they reported on RTP after surgical treatment for AC joint dislocation. Statistical analysis was performed with SPSS. RESULTS: We found 120 studies including 4327 cases meeting our inclusion criteria. The majority of patients were male (80.2%), with a mean age of 37.2 years (range, 15-85) and a mean follow-up of 34.5 months. Most were recreational athletes (79%), and the most common sport was cycling. The overall rate of RTP was 91.5%, with 85.6% returning to the same level of play. Among collision athletes, the rate of RTP was 97.3%, with 97.2% returning to the same level of play. In overhead athletes, the rate of RTP was 97.1%, with 79.2% returning to the same level of play. The mean time to RTP was 5.7 months (range, 1.5-15). Specific RTP criteria were reported in the majority of the studies (83.3%); time to return to play was the most commonly reported item (83.3%). Type III Rockwood injuries had the highest RTP rate at 98.7% and the earliest RTP at 4.9 months. Among the different surgical techniques, Kirschner wire fixation had the highest rate of RTP at 98.5%, while isolated graft reconstruction had the earliest RTP at 3.6 months. CONCLUSION: The overall rate of RTP was reportedly high after surgical treatment for AC joint dislocation, with the majority of patients returning to their preinjury levels of sport. There is a lack of consensus in the literature for what constitutes a safe RTP, with further focus on this topic required in future studies.

Cationic complexes of iridium: diiodobenzene chelation, electrophilic behavior with olefins, and fluxionality of an Ir(I) ethylene complex.

The synthesis of a series of dicationic Ir(III) complexes is described. Reaction of Ir(CO)(dppe)I (dppe = 1,2-bis(diphenylphosphino)ethane)) with RI (R = CH(3) and CF(3)) results in formation of the Ir(III) precursors IrR(CO)(dppe)(I)(2) (R = CH(3) (1a) and CF(3) (1b)). Subsequent treatment with AgOTf (OTf = triflate) generates the bis(triflate) analogues IrR(CO)(dppe)(OTf)(2) (R = CH(3) (2a) and CF(3) (2b)), which undergo clean metathesis with NaBARF (BARF = B(3,5-(CF(3))(2)C(6)H(3))(4)(-)) in the presence of 1,2-diiodobenzene (DIB) forming the dicationic halocarbon adducts [IrR(CO)(dppe)(DIB)][BARF](2) (R = CH(3) (3a) and CF(3) (3b)). Complexes 3a and 3b demonstrate facile exchange chemistry with acetonitrile and carbon monoxide forming complexes 4 and 5, respectively. NMR investigation of the mechanism reveals that the process proceeds through an eta(1)-diiodobenzene adduct, where labilization at the coordination site trans to the alkyl group occurs first. Complex 3a reacts with ethylene forming the cationic iridium(I) product [Ir(C(2)H(4))(2)(CO)(dppe)][BARF] (6), which demonstrates fluxional behavior. Variable-temperature NMR studies indicate that the five-coordinate complex 6 undergoes three dynamic processes corresponding to ethylene rotation, Berry pseudorotation, and intermolecular ethylene exchange in order of increasing temperature based on NMR line shape analyses used to determine the thermodynamic parameters for the processes. The DIB adducts 3a and 3b were also found to promote olefin isomerization of 1-pentene, and polymerization/oligomerization of styrene, alpha-methylstyrene, norbornene, beta-pinene, and isobutylene via cationic initiation.