Changes in Femoral Posterior Condylar Offset, Tibial Posterior Slope Angle, and Joint Line Height after Cruciate-Retaining Total Knee Arthroplasty

PURPOSE: Changes in the femoral posterior condylar offset (PCO), tibial posterior slope angle (PSA), and joint line height (JLH) after cruciate-retaining total knee arthroplasty (CR-TKA) were evaluated to determine their influence on the flexion angle. MATERIALS AND METHODS: A total of 125 CR-TKAs performed on 110 patients were retrospectively reviewed. Pre- and postoperative PCO, PSA, and JLH were compared using correlation analysis. Independent factors affecting the postoperative flexion angle of the knee were analyzed. RESULTS: The PCO was 28.2+/-2.0 mm (range, 24.5 to 33.1 mm) preoperatively and 26.7+/-1.8 mm (range, 22.2 to 31.2 mm) postoperatively (r=0.807, p0.291). CONCLUSIONS: Although the PCO and JLH did not change significantly after CR-TKA, the PSA decreased by 5.5degrees with a small range of variation. Restoration of the PCO and JLH could promote optimization of knee flexion in spite of the decreased PSA after CR-TKA.

Change in Neural Tube Size for a Lumbar Spinal Stenosis Patient on Axial Loading Magnetic Resonance Imaging / 대한정형외과학회잡지

PURPOSE: A conventional magnetic resonance imaging (MRI) was conducted in supine position, showing a slight different from that conducted in upright position. Therefore, we simulated the upright position by applying the axial load on a lumbar spinal stenosis patient and measured the change of neural tube size in axial load and standardized the data. MATERIALS AND METHODS: We compared the axial loading MRI obtained from spinal stenosis patients who visited Wonkwang University Hospital outpatient clinic between October 2010 and May 2011 showing radiologic and physical symptoms. RESULTS: Neural tube sizes by conventional MRI were as follows: 195.57 mm² and 203.20 mm² on average between the left and right sides in L3/4; 194.64 mm² and 211.43 mm² on average in L4/5; and 199.38 mm² and 203.04 mm² on average in L5/S1. Neural tube sizes by axial loading MRI were as follows: 166.43 mm² and 174.27 mm² on average between the left and right sides in L3/4; 154.81 mm² and 158.67 mm² on average in L4/5; and 148.48 mm² and 157.19 mm² on average in L5/S1. Changes of neural tube sizes in L3/4, L4/5, and L5/S1 had a significant correlation (p<0.05). CONCLUSION: The axial loading device was an excellent tool in simulating the upright position for spinal stenosis patients, and the change of neural tube sizes reproduced for the upright position was statistically significant. This is thought to be meaningful for clinical applicability.

Rotator Cuff Repair in Patients over 75 Years of Age: Clinical Outcome and Repair Integrity

BACKGROUND: Some studies have shown significant functional improvement after rotator cuff (RC) repair in elderly patients. However, few studies have reported the healing potential of RC tears in elderly patients. METHODS: Twenty-five patients aged ≥ 75 years who underwent RC repair were enrolled. The mean age at the time of surgery was 78.3 years (range, 75 to 88 years) while the mean follow-up was 36.3 months (range, 18 to 114 months). We evaluated clinical and structural outcomes after RC repair in the retear and healed groups. RESULTS: Of 25 patients, 16 (64%) had healed RC lesions and 9 (36%) had retorn cuff lesions. The retear rate increased significantly with increasing initial tear size (small to medium, 13%; large, 60%; massive, 80%; p = 0.024) but not with increasing age (p = 0.072). The mean visual analog scale (VAS), University of California Los Angeles (UCLA), and Constant scores significantly improved from 5.2, 15.8, and 49.3 preoperatively to 1.4, 31.1, and 71.9 in the healed group and from 6.0, 14.4, and 39.5 preoperatively to 2.4, 28.3, and 63.6 in the retear group at the final follow-up (p < 0.05, respectively). There were no significant differences in clinical outcomes between the 2 groups at the final follow-up. Retear was significantly correlated with initial tear size (p = 0.001; odds ratio [OR], 2.771; 95% confidence interval [CI], 1.394 to 5.509 for large to massive tears) (p = 0.001; OR, 0.183; 95% CI, 0.048 to 0.692 for small to medium tears). CONCLUSIONS: There were significant improvements in clinical outcomes after RC repair in patients ≥ 75 years. Structural integrity after cuff repair did not affect the final clinical outcome. Even in elderly patients aged ≥ 75 years, healing of repaired RC can be expected in cases of small to medium tears. Although the retear rate was relatively high for large to massive tears, clinical outcomes still showed significant improvement.

Clear Cell Chondrosarcoma of the Tibia Diaphysis: A Case Report / 대한골관절종양학회지

Clear cell chondrosarcoma is a very rare malignant bone tumor that shows a strong predilection for the epiphysis or metaphysis of long bones. Many studies have reported that the proximal end of the femur is the most commonly affected site, followed by the proximal end of the humerus. Histopathologically, tumor cells of this type have centrally located round nucleoli with clear cytoplasm and a distinct cytoplasmic membrane. Generally, clear cell chondrosarcomas is not confused with conventional chondrosarcomas. However, when it involves the diaphysis in long bones, diagnosis can be hindered, as only three reports of this exist in the literature. We report herein an unusual case of clear cell chondrosarcoma of the tibial diaphysis in a 42-year-old male.