A Retrospective Comparative Study of Internal Fixation with Contoured Plate Using Bicortical Screw Versus a Double Plate in Comminuted Olecranon Fractures / 대한정형외과학회잡지

PURPOSE: To analyze the clinical result of a contoured plate fixation using a bicortical screw and a double plate fixation in the surgical treatment of an adult's comminuted olecranon fracture. MATERIALS AND METHODS: A total of 22 patients were classified by Mayo classification as Type IIB (17) and Type IIIB (5). All patients enrolled in the study were treated between July 2002 and September 2009. Twelve patients were operated on using the contoured plate internal fixation using a bicortical screw procedure classified as group 'A'. The 10 patients operated on by a double plate fixation were classified as group 'B'. The Mayo elbow performance score was used to compare postoperative clinical results based on total points in 4 categories: pain, range of motion, articular stability, and articular function. RESULTS: The clinical results of using the Mayo elbow performance score of group 'A' were that 10 scored in the 'excellent' range and 2 scored in the 'good' range the following: in group 'B' were in the excellent range and 3 were in the good range. Both groups showed satisfactory results. Postoperative elbow exercises in group 'A' commenced 7.8 (5-14) days on average, postoperatively. For 'B' group, post-operative elbow exercises began 4.5 (3-7) days following the operation. With regard to the exercise and the range of elbow motion, group 'A' averaged 113.5 degrees and group 'B' averaged 112 degrees. After surgery, the average durations until the bone union were 3.8 (2.4-5.6) months for group 'A' and 4 (2.5-5) months for group 'B', respectively. CONCLUSION: There was no significant difference in the clinical results between patients treated with the contoured plate internal fixation using a bicortical screw or the internal fixation using a double plate in the surgical treatment of adults with comminuted olecranon fracture or dislocation. Therefore, both types of operative approach are acceptable.

Comparision of Non-locking Monocortical and Bicortical Screw System for Anterior Cervical Fusion and Plating in Degenerative Cervical Spondylosis

OBJECTIVE: Non-locking bicortical screw and locking monocortical screw system have usually been used in anterior cervical spine fusion and plating. The purpose of this study is to evaluate the differences in stability and safety between the non-locking bicortical and monocortical screw-plate system. METHODS: The authors reviewed 135 cervical spondylotic patients who underwent anterior cervical fusion from Jan. 1995 through Jun. 2002. The patients were separated into two groups: Group 1. consisted of 68 patients (male: 55, female 13 and mean age: 50.5years) treated with non-locking bicortical screw system, Group 2. consisted of 67 patients (male 50, female 17, mean age: 59.6 years) treated with non-locking monocortical screw system. The mean follow-up duration was 50 months (from 9 to 101 months). A comprehensive evaluation between two groups were made. RESULTS: There were no graft material related complications in both groups. But instrument related complications were 1 case of screw breakage and 1 case of screw loosening in group 1 and 1 case of screw loosening in group 2. Mean time for plate and screw fixation was less required in group 2 than group 1. Fusion had occurred in all patients of both groups. CONCLUSION: Non-locking monocortical screw fixation can be recommended for anterior cervical fusion and plating in degenerative disease, making the procedure quicker, easier, and safer compare with non-locking bicortical screw.

Biomechanical analysis of mandibular bilateral sagittal split ramus osteotomy with bicortical screws internal fixation / 实用口腔医学杂志

Objective: To study the mandibular bilateral sagittal split ramus osteotomy (BSSRO) with bicortical screws rigid internal fixation(RIF) with the three-dimensional finite element method, and supply directions for clinic practice.Methods:CT scanned technology and the finite element software (Ansys) were used to establish the three-dimensional finite element model of BSSRO with bicortical screws RIF. The stress distribution of the mandible and the RIF and the displacement of split mandible were calculated under three kind of occlusion situation.Results:Under the same kind of occlusion situation, the stress and displacement of the split mandible with single upper screws fixation was higher than that with the reverse "L" screws fixation, the stress and displacement of the split mandible with 2.0 mm diameter screws fixation was higher than that with 2.7 mm diameter screws fixation. With the same kind of fixation method, the stress and the displacemen of the mandible under the incisor occlusion was the highest.Conclusion:The fixation distance, position, distribution angle of the bicortical screws all have effects on the fixation stability. The patient should avoid the incisor occlusion after the surgery.

The Efficacy of the Unicortical Screw in the Anterior Cervical Fusion of the Degenerative Cervical Spine Disease

Anterior cervical fusion without internal fixation destabilizes an already unstable spine and can result in tenuous bone graft stability and potential for incorporation. Anterior fusion of cervical spine with screw-plates is gaining in popularity in the management of anterior cervical spine instability. Eighty six cases that underwent anterior fusion with or without internal fixation and autogenous iliac bone graft were compared and analyzed. The pathologies included 40 cases of cervical disc disease, 43 of cervical spondylosis and 3 of ossification of posterior longitudinal ligament. Changes in the alignment of the total cervical spine and of the fused segment were evaluated in both groups. Dislodgement of the grafted bone, which was observed in 2 of 11 cases in the nonplate group, was not seen in the plate group. Hardware failure was developed in 3 of 24 cases in the bicortical group, but not in 51 cases in the unicortical group. Alignment of the cervical spine was corrected and relatively well manintained in the plate group compared with the nonplate group. We concluded that a unicortical screw fixation was superior than a bicortical screw and a fusion without plating system could not keep a cervical lordotic curve in the treatment of the degenerative cervical disease.

Anterior Cervical Fusion: A Retrospective Analysis of 152 Cases

Anterior cervical fusion has enjoyed an increasing acceptance and frequency of utilization in the treatment of symptomatic degenerative, traumatic, and neoplastic disorders. Since the introduction of plate systems, cervical fusion with fixation has become popularized. We present our experiences of 152 cases of cervical fusion in degenerative and traumatic lesions, focusing on their surgical results and complications, along with our opinions about the various plate systems we used. Between March 1993 and May 1996, 152 patients with symptomatic degenerative and traumatic cervical lesions between C3-4 and C7-T1 levels were treated with anterior cervical fusions. These patients were retrospectively studied according to their medical records and radiological studies. A comparison between various plate systems were also done. There were 110 men and 42 women, aged from 21 to 77 years. Mean follow up period was 17 months. Mean fused segments were 1.4. Various plate systems were used: Caspar plate system in 14 patients; Top plate in 102; Orion plate in 21; and none in 15. Dislodgement of bone graft, screw loosening, and fusion failure that required reoperation were occurred in 8 cases. None of them were initially treated with unicortical type screws. Asymptomatic esophageal perforation was developed in one case among them. In conclusion, anterior cervical fusion with screw plate system can be carried out with acceptable complication rate. Although relative follow up period was short, we concluded that the locking type screw plate system was superior than the classic bicortical screw system in their procedural simplicity, unnecessary penetration of posterior cortex, and elimination of the fear for the neurological complication.