Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Q: Restoration of posterior condylar offset during TKA is believed to be important to improving knee kinematics, maximizing ROM, and minimizing flexion instability. However, controversy exists regarding whether there are important anatomic differences between sexes and whether a unisex knee prosthesis can restore the anatomy of knees in males and females.', 'The purposes of our study were to determine if sex differences exist in (1) absolute posterior condylar offset size, (2) relative posterior condylar offset size in relation to total condylar height, and (3) posterior condylar articular cartilage thickness.', 'We identified 100 patients (50 men and 50 women) without a history of arthritis, deformity, dysplasia, osteochondral defect, fracture, or surgery about the knee who had MRI of the knee performed. All MR images were ordered by primary care medical physicians for evaluation of nonspecific knee pain. Using a previously described three-dimensional MRI protocol, we measured posterior condylar offset, total condylar height, and articular cartilage thickness at the medial and lateral femoral condyles and compared values to evaluate for potential sex differences. We performed an a priori power calculation using a 2-mm posterior condylar offset difference as the minimum clinically important difference; with 2n = 100, our power to detect such a difference was 99.8%.', 'Compared with females, males had greater medial posterior condylar offset (30 mm [95% CI, 29.3-30.7 mm; SD, 2.5 mm] vs 28 mm [95% CI, 27.0-28.5 mm; SD, 2.7 mm]), lateral posterior condylar offset (27 mm [95% CI, 26.2-27.3 mm; SD, 2.0 mm] vs 25 mm [95% CI, 24.2-25.4 mm; SD, 2.0 mm]), medial condylar height (63 mm [SD, 3.2 mm] vs 57 mm [SD, 4.4 mm]), and lateral condylar height (71 mm [SD, 5.2 mm] vs 65 mm [SD: 4.0 mm]) (all p values < 0.001). However, the mean ratio of medial posterior condylar offset to medial condylar height (0.48 [SD, 0.04] vs 0.49 [SD, 0.05]) and the mean ratio of lateral posterior condylar offset to lateral condylar height (0.38 [SD, 0.05] vs 0.38 [SD, 0.03]) were not different between sexes (p = 0.08 and p = 0.8, respectively). There also was no sex difference in mean articular cartilage thickness at either condyle (medial condyle: 2.7 mm [SD, 0.5 mm] vs 2.5 mm [SD, 0.7 mm]; lateral condyle: 2.6 mm [SD, 0.6 mm] vs 2.5 mm [SD, 0.8 mm]) (both p values ≥ 0.1).

A: Do no sex differences exist in posterior condylar offsets of the knee?
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Q: Reports on outcome after posterior cruciate ligament (PCL) reconstruction often contain both isolated PCL and combined knee ligament injuries. This makes it difficult to conclude on the outcome after reconstruction of isolated PCL injuries.', 'To investigate the outcome after PCL reconstruction in patients with an isolated PCL injury and to compare this with the outcome of patients treated with reconstruction after isolated anterior cruciate ligament (ACL) injuries.', 'Cohort study; Level of evidence, 3.', 'Seventy-one patients with an isolated PCL injury that was reconstructed surgically and who had registered in the Norwegian Knee Ligament Registry between 2004 and 2010 were included in this study. Patients with isolated ACL reconstructions (n = 9661) who had registered in the same period were included for comparison. Knee Injury and Osteoarthritis Outcome Score (KOOS) was used as the patient-reported outcome measure. Preoperative and 2-year postoperative KOOS scores were compared. Changes in KOOS score reported by the PCL patients were compared with changes reported by the ACL patients.', 'At the 2-year postoperative follow-up of the PCL-reconstructed patients, the patient-reported outcome was improved, measured by KOOS as follows: pain, 15.1 (95% CI, 8.5-21.8; P < .001); symptoms, 0.9 (95% CI, -6.6 to 8.3; P = .82); activities of daily living, 13.2 (95% CI, 6.6-13.9; P < .001); sports, 20.7 (95% CI, 11.8-29.4; P < .001); and quality of life, 26.6 (95% CI, 18.9-34.2; P < .001). According to the KOOS, the incremental improvements were similar for PCL and ACL patients. Time from injury to surgery was longer for the PCL patients compared with ACL patients (median, 21.5 vs 8.0 months; P < .001).

A: Do patients With Isolated PCL Injuries Improve From Surgery as Much as Patients With ACL Injuries After 2 Years?
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Q: To determine whether treatment with corticosteroids decreases the incidence of postextubation airway obstruction in an adult intensive care unit.', 'Clinical experiment.', 'Adult medical and surgical intensive care unit of a teaching hospital.', 'One hundred twenty-eight patients who were intubated for >24 hrs with a cuff leak volume <24% of tidal volume and met weaning criteria.', ': Patients were randomized into a placebo group (control, n = 43) receiving four injections of normal saline every 6 hrs, a 4INJ group (n = 42) receiving four injections of methylprednisolone sodium succinate, or a 1INJ group (n = 42) receiving one injection of the corticosteroid followed by three injections of normal saline. Cuff volume was assessed 1 hr after each injection, and extubation was performed 1 hr after the last injection. Postextubation stridor was confirmed by examination using bronchoscopy or laryngoscopy.', 'The incidences of postextubation stridor were lower both in the 1INJ and the 4INJ groups than in the control group (11.6% and 7.1% vs. 30.2%, both p < .05), whereas there was no difference between the two treated groups (p = .46). The cuff leak volume increased after the second and fourth injection in the 4INJ group and after a second injection in the 1INJ group compared with the control group (both p < .05).

A:
Does intravenous injection of methylprednisolone reduce the incidence of postextubation stridor in intensive care unit patients?
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