Introduction. Bisphosphonates are among the most commonly prescribed drugs in Osteoporotic Patients. Their mode of action is anti-resorptive. Since remodeling is a key step in fracture healing, there has been concern regarding the effect of bisphosphonates on fracture healing. Objectives. To assess the effect of alendronate on fracture healing in the rabbit ulna osteotomy model. Materials and methods. 16 New Zealand white rabbits were divided into 2 equal groups. Bilateral ulnar osteotomies were performed in the first week. Group 1 was the control group and group 2 was gavaged with alendronate solution (human equivalent dose). 2 rabbits were euthanised at 3 and 6 weeks and the remaining 4 rabbits were euthanised at 8 weeks. Fracture healing was assessed radiologically, with mechanical testing using the Instron 4302 materials testing machine and histologically, in that order. Results. The fractures healed satisfactorily in all the control group animals. However, in the alendronate treated group, there was an abundance of woven bone and little lamellar bone in the callus. However there was no significant difference in mechanical testing. In addition we did not find any evidence of Osteonecrosis in the Bisphosphonate treated group. Conclusion. Bone remodelling in the alendronate treated group is slower but a larger amount of bone callus is formed around the fracture, thus giving the fracture callus a higher ultimate load to failure at an earlier stage

Ten cases of missed Monteggia lesions were reviewed following treatment. Four cases were treated with an ulnar osteotomy, open reduction of radial head and annular ligament reconstruction (Group A). In six cases only an open reduction of the radial head was performed with an ulnar osteotomy (Group B). No annular ligament reconstruction was done in Group B. The mean age seven in both groups (range 4-12 years). The children presented three months to 24 months after the initial injury. Nine patients were classified as Bado type I, and one with Bado type III injury. The mean follow-up was 20 months (8-26 months) after surgery. In both groups the ulnar osteotomy healed uneventfully. In group A, there was one superficial infection, the mean loss of pronation was 12 degrees and in one case the radial head re-subluxed. In group B, the mean loss of pronation was 10 degrees. Elbow flexion was comparable to Group A. No radial head subluxation was seen in this group. No child in either group had any functional limitation in activities. Thus, in chronic Monteggia lesion, annular ligament reconstruction is not always required to restore radio-capitellar alignment. Open reduction of radial head with an ulnar osteotomy and stable fixation will suffice. Ligament reconstruction will not stabilise an inadequately reduced radial head

Purpose of Study. We report the outcome of five cases of chronic paediatric Monteggia lesion treated with a modified Bell-Tawse procedure. Methods. Five patients with a chronic Monteggia lesion were treated over an eight-year period (2004–2012) at our institution. All underwent a modified Bell-Tawse procedure. The patient medical records were retrospectively analysed. We report the outcome in five patients. Results. Four girls and one boy were treated for a chronic Monteggia lesion in the period studied. The mean age at time of surgery was 8 years old (range 4–14 years). The mechanism of injury was post-traumatic in four of the five cases, while in one case the mechanism was uncertain. All children underwent modified Bell-Tawse procedure. All children ultimately required ulnar osteotomy, while two also required radial osteotomy. At a mean follow-up of 22 months (range 16–38 months), four children had experienced complications. Symptomatic metalwork was removed in one case, two children re-dislocated the affected joint, and one child required revision Bell-Tawse procedure. No nerve palsies were noted on follow-up. Conclusion. Paediatric elbow trauma necessitates early, senior management. We report a series of five patients who underwent modified Bell-Tawse procedure for chronic Monteggia lesion. Four of the five children experienced complications. All required shortening osteotomies. The chronic Monteggia lesion is an unusual but troublesome presentation in the paediatric population. Further research in the area is necessary

Clinical assessment of elbow deformity in children at present is mainly based on physical examination and plain X-ray images, which may be inaccurate if the elbow is not in fully supination; furthermore, the rotational deformity is even harder to be determined by such methods. Morrey suggested that the axis of rotation of the elbow joint can be simplified to a single axis. Based on such assumption, we are proposing a method to assess elbow deformity using rotational axis of the joint, and an optimized calculation algorithm is presented. The rotation axis of elbow in respective to the upper arm can be obtained from the motion tract of markers placed at the forearm. Cadaver study was done, in which three skeletal motion trackers were placed over both the anterior aspect of humerus, as well as distal ulna. Osteotomy was created at the supracondylar region of humerus through lateral approach, and the bone fragments were stabilized with a set of external skeletal fixator, leaving the soft tissue intact. The amount of deformity was created manually by adjusting the position of the distal fragment via skeletal fixator. Ultrasound 3D motion tracking system from Zebris® was used in this study, and the program was developed under the Matlab environment. Cycles of passive elbow flexion/extension motion were carried out for each set of deformity. The data were initially transformed to humerus coordinate, and since the upper arm was not absolutely stationary, its influence on the measured position of ulna was adjusted. With this adjusted data, a best fit plane that would include most of the ulna positions (MU) within a minimal distance was obtained. The rotation axis was calculated as the normal vector to this plane, and the carrying angle could subsequently be assessed according to the relationship between this axis and the x-axis on the xy-plane as well as on the xz-plane. Fresh frozen cadaver study was conducted in the Medical Simulation Center at Tzu-Chi University. After adjustment of the raw data to eliminate the influence of humerus motion, the ulna motion could be narrowed down from a band of 10mm to 3mm, with a significant smaller standard deviation. The rotation axis was obtained by the normal vector to the best fit plane. Two different approaches were attempted to find the plane. In the first method, the plane was obtained via least square method from the adjusted ulna positions, and the second method found the plane via RANSAC method. Calculations were repeated several times for each method, and the results showed a variation of 5 degrees in the first method and about 2 degrees in the second method. Rotational axis can be used to define the 3-dimensional deformity of elbow joint; however, it is difficult to obtain such axis accurately due to hypermobility and multi-directional motion of the shoulder joint. In this study, we have developed another method to assess the elbow deformity using motion analysis system instead of the conventional image studies, and this may be applicable clinically if the facility becomes more accessible in the future. (This research was supported by the project TCRD-TPE-99-30 granted by the Buddhist Tzu-Chi General Hospital, Taipei Branch)

After a fracture of the distal radius, the bone segments may heal in a suboptimal position. This condition may lead to a reduced hand function, pain and finally osteoarthritis, sometimes requiring corrective surgery. The contralateral unaffected radius is often used as a reference in planning of a corrective osteotomy procedure of a malunited distal radius. In the conventional procedure, radiographs of both the affected radius and the contralateral radius have been used for planning. The 2D nature of radiographs renders them sub-optimal for planning due to overprojection of anatomical structures. Therefore, computer-assisted 3D planning techniques have been developed recently based on CT images of both forearms. The accuracy of using the contralateral forearm for CT based 3D planning the surgery of the affected arm and the optimal strategy for planning have not been studied thoroughly. To estimate the accuracy of the planned repositioning using the contralateral forearm we investigated bilateral symmetry of corresponding radii and ulnae using 3-dimensional imaging techniques. A total of 20 healthy volunteers without previous wrist injury underwent a volumetric computed tomography scan of both forearms. The left radius and ulna were segmented to create virtual 3 dimensional models of these bones. We selected a distal part and a larger proximal part from these bones and matched them with a mirrored CT-image of the contralateral side. This allowed estimation of the accuracy by calculation of relative displacements (Δx, Δy, Δz) and rotations (Δψx, Δψy, Δψz) required to align the left bone with the right bone segments as a reference. We also investigated the relationship between longitudinal length differences in radius and ulna and utilised this relationship to arrive at an optimal planning of the length of the affected radius after surgery. Relative differences in displacement and orientation parameters after planning based on the contralateral radius were (Δx, Δy, Δz): −0.81±1.22 mm, −0.01±0.64 mm, and 2.63±2.03 mm; and (Δψx, Δψy, Δψz): 0.13°±1.00°, −0.60°±1.35°, and 0.53°±5.00°. The same parameters for the ulna were (Δx,Δy, Δz): −0.22±0.82 mm, 0.52±0.99 mm, 2.08±2.33 mm; and (Δψx, Δψy, Δψz): −0.56°±0.96°, −0.71°±1.51°, and −2.61°±5.58°. The results also point out that there is a strong linear relationship between absolute length differences (Δz) of the radius and ulna among the individuals. Since we observed substantial length difference of the longitudinal bone axes of both forearms in healthy individuals, including the length difference of the adjacent forearm bones in the planning turned out to be useful in improving length correction in computer-assisted planning of radius or ulna osteotomies. The improved planning markedly reduces length positioning variability, (from 2.9± 2.1 mm to 1.5 ± 0.6 mm). We expect this approach to be valuable for 3-D planning of a corrective distal radius osteotomy. Awareness of the level of bilateral symmetry is important in reconstructive surgery procedures when the contralateral unaffected side is used as a reference for planning and evaluation. Bilateral asymmetry may introduce length errors into this type of preoperative planning that can be reduced by taking into account the concomitant ulnae asymmetry