Evaluation of the Circles Measurement and the ABC Classification of Acromioclavicular Joint Injuries.

BACKGROUND: Acromioclavicular joint (ACJ) injuries are common. Despite this, it remains unclear how best to assess, classify, and manage these cases. A simple, reliable, valid, and accurate radiographic parameter to measure ACJ displacement would allow improved consistency of diagnosis and subsequent treatment pathways. PURPOSE: To evaluate "the circles measurement" and associated "ABC classification" as a tool for assessing ACJ displacement and injury classification. STUDY DESIGN: Descriptive laboratory study. METHODS: The circles measurement is taken from a lateral Alexander radiograph of the shoulder. The measurement is the center-to-center distance between 2 circles drawn to define the lateral extent of the clavicle and the anteromedial extent of the acromion; it is independent of the displacement plane, judging total ACJ displacement in any direction rather than trying to quantify vertical and/or horizontal displacement. When utilized clinically, the circles measurement is a single measurement calculated as the difference between values recorded for the injured and uninjured sides. Validation of the circles measurement was performed using lateral Alexander radiographs (including ±20° projection error in all planes) and computed tomography of standardized ACJ injury simulations. We assessed inter- and intrarater reliability, convergent validity, and discriminant validity of the circles measurement and subsequently generated a classification of ACJ injury based on displacement. RESULTS: Reliability and validity of the circles measurement was excellent throughout. Interrater reliability (ICC [intraclass correlation coefficient] [2,1], 95% CI; n = 78; 4 observers) was 0.976 (0.964-0.985). Intrarater reliability (ICC [2,1]; 95% CI; n = 78; 2 measures) was 0.998 (0.996-0.998). Convergent validity (Pearson correlation coefficient, r) was 0.970 for ideal radiographs and 0.889 with ±20° projection error in all planes. Discriminant validity, with 1-way analysis of variance, showed a P value of <.0001 and effect size (η2) of 0.960, with the ability to distinguish between the previously defined stable (Rockwood IIIA) and unstable (Rockwood IIIB) injuries. The results permitted objective, statistically sound parameters for the proposed ABC classification system. CONCLUSION: The circles measurement is a simple, reliable, valid, accurate, and resilient parameter for assessing ACJ displacement and can be used in conjunction with the proposed ABC classification to define ACJ injuries more accurately and objectively than previously described. CLINICAL RELEVANCE: This novel parameter has the potential to standardize the initial assessment and possibly the subsequent clinical management of ACJ injuries, in addition to providing a standardized measure for future research.

Penetration of a topically administered anti-tumor necrosis factor alpha antibody fragment into the anterior chamber of the human eye.

OBJECTIVE: To determine whether topically applied ESBA105, a single-chain antibody fragment against tumor necrosis factor (TNF)-α, could efficiently penetrate into the anterior chamber of the human eye. DESIGN: Multicenter, interventional cohort study. PARTICIPANTS: Otherwise healthy patients undergoing cataract surgery (cohorts I-III) or combined cataract surgery and vitrectomy (cohort IV). METHODS: ESBA105 (n = 57) or placebo (n = 22) was preoperatively applied as eye drops to 1 eye in patients scheduled for cataract surgery (n = 73) or combined cataract surgery and vitrectomy (n = 6). ESBA105 was administered on the day of surgery at 1-hour intervals (last dose 1 hour preoperatively) as 1.6 mg in 4 drops for cohort I (n = 15) and as 3.2 mg in 8 drops for cohorts II (n = 15) and IV (n = 6). Cohort III (n = 43) was randomized 1:1 in double-masked fashion to receive either ESBA105 6.4 mg or placebo over 4 days using 4 drops per day at 4-hour intervals (last dose 12 hours preoperatively). Aqueous humor (all cohorts), vitreous humor (cohort IV only), and blood samples (all cohorts) were collected for measurement of ESBA105. MAIN OUTCOME MEASURES: ESBA105 intraocular concentration. RESULTS: Both 4 times daily over 4 days dosing (cohort III) and 8 times daily dosing (cohorts II and IV) resulted in reliably high ESBA105 concentrations in aqueous humor. Mean molar excess of intraocular ESBA105 over its target (intraocular TNF-α) was calculated as 96-fold (cohort III) to 359-fold (cohorts II and IV). Results from the cohorts receiving 4 and 8 hourly drops per 1 day (cohorts I, II, and IV) indicated that dose-dependent intraocular concentrations of ESBA105 were achieved within hours of dosing. After 8 times daily dosing, 5 of 6 vitreous samples (cohort IV) had undetectable ESBA105 levels. ESBA105 was detected in 17 of 55 preoperative serum samples but no longer detectable in serum 1 day after surgery (0 of 19 samples). In cohort III, treatment-emergent adverse events were identical between ESBA105 and placebo groups (2 cases each of eye irritation). CONCLUSIONS: These results demonstrate that the topically applied single-chain antibody fragment ESBA105 penetrated into the anterior chamber of the human eye at therapeutic levels.