Mechanical properties and cytotoxicity of PLA/PCL films

Thermodynamically immiscible poly(lactic acid) (PLA) and poly(ε-caprolactone) (PCL) were blended and solution-cast by adding the 3% compatibilizer (tributyl citrate, TBC) of the PCL weight. In the PLA/PCL composition range of 99/1–95/5 wt%, mechanical properties of the PLA/PCL films with TBC were always superior to those of the films without TBC. The tensile strength of 42.9 ± 3.5 MPa and the elongation at break of 10.3 ± 2.7% were observed for the 93/7 PLA/PCL films without TBC, indicating that PCL addition is effective for strength and ductility. However, the tensile strength of 54.1 ± 3.4 MPa and the elongation at break of 8.8 ± 1.8% were found for the 95/5 PLA/PCL with TBC, indicating that the effect of co-addition of PCL and TBC on mechanical properties of the films is more pronounced. No cytotoxicity was observed for the PLA/PCL films regardless of TBC addition.

Arthroscopic Management of the Tibial Condylar Fractures / 대한정형외과학회잡지

Fractures of the tibial condyles, involving as they do weight-bearing articular surfaces and frequently accompanied by soft tissue injuries such as collateral ligaments, cruciate ligaments, and menisci present a variety of problems in treatment and prognosis. Slee, Apley, and others maintained the opinion that most fractures of the tibial condyles could be managed conservatively. On the other hand, Rombold, Schatzker, and others seemed to consider closed treatment to be virtually s form of therapeutic nihilism and adviced open reduction. But recently most authors agree that the method of treatment has to be selected in each individual case, and recommand anatomical reduction of the fracture as possible and early knee motion. The authors have treated 17 cases of tibial condylar fractures with arthroscopic management and extraarticular distal approach in the Department of Orthopedic surpery, Kang Dong Sacred Heart Hospital from Oct. 1986 to Jul. 1989. Of the above cases, 11 cases could be followed for a period of anywhere from 1 year to 31/2 years and analysed according to the cause, classification, treatment, and result. The following results were obtained from the analysis of 11 tibial condylar fractures. l. Of the 11 cases, 7 (63.6%) were male and 4 (36.4%) were female. 2. Of the 11 cases, 7 (63.6%) were due to traffic accident (5 pedestrians, 2 occupants) and 3 (27.3%) were due to fall from height. 3. Among 11 cases, 7 (63.6%) were associated with other injuries. 4. Bone graft was needed in 5 cases. 5. All were treated by arthroscopic management with anatomically and functionally good results. 6. By arthroscopic mangement, it was easy to find and treat the accompanying intraarticular lesion. 7. With early active and C.P.M. exercise, almost full range of motion was obtained in all cases.

Treatment of the Unstable Thoracolumbar Fractures Using Cotrel / 대한정형외과학회잡지

Surgical stabilization using instrumentation for thoracolumbar injuries offers several advantages such as nearly anatomic reduction of fractures, protection of neurologic structures and most importantly early ambulation of the patient. The treatment of fracture-dislocation of the thoracolumbar spine has been progressively improved over the past decades and recently a lot of new device have been introduced to improve fixability of the involved vertebrae three dimensionally and short segmental fixation as possible. The authors have treated 17 cases of unstable thoracolumbar fracture using Cotrel-Dubousset instrumentation in the Department of Orthopedic Surgery, Kangdong Sacred Heart Hospital from Jan. 1988 to Jan. 1989 with the following results: 1. Bursting fractures are the most common type(52.9%) of mechanism of injury. 2. Excellent anatomic reductions were obtained and compression, wedging and local kyphotic deformities were nicely corrected. 3. Short segmental fixation can preserve the maximal spinal mobility. 4. No significant loss of reduction or loosening of implant was found. 5. Remarkable neurologic recoveries were observed in cases of incomplete cord lesion. 6. Significant neurologic recovery was found in patients treated with laminectomy and Cotrel-Dubousset instrumentation.