Currently available fracture fixation devices that were originally developed for healthy bone are often not effective for patients with osteoporosis. Resulting outcomes are unsatisfactory, with longer recovery times, often requiring re-surgery for failed cases. One major issue is the design of bone screws, which can loosen or pull-out from osteoporotic bone. Design improvements are possible, but the development of new screws is a lengthy and expensive process due to the manufacture of the complex geometry involved. The aim of this research was to validate our currently available 3D printing technology in the design, manufacture and testing of screws.

Three standard wood screw designs were reverse-engineered using computational modelling and then fabricated in polymeric resin using 3D rapid prototyping on a Stereolithography (SLA) machine. The original metal screws and the 3D screws (n=5 of each) were then inserted into a synthetic bone block (Sawbones, PCF5) representing the mechanical properties of severely osteoporotic cancellous bone. Pull-out tests were conducted in accordance with ASTM 543-13.

The three metal screws exhibited pull-out strengths of 125, 74 and 118 N respectively. The 3D printed screws by comparison showed pull-out strengths approximately 15–20 % lower than their metal counterparts. However, when the results were normalised to the material tested, showing the relative changes to the first design, the pattern of results in the metal and 3D printed groups were almost identical (within 3 % of each other), showing excellent correlation.

This study is the first to show that 3D Rapid Prototyping can be used in the pre-clinical testing of orthopaedic screws. The methodology provides a cheaper, faster development process for screws, allowing huge scope for development and improvement. Future work will include expanding the study to include more screw configurations as well as testing in higher density foams to compare performance in healthier bone.

Purpose of Study: To assess the efficacy of two-stage correction (skeletal traction followed by Partial Fasciec-tomy) in treating severe Dupuytren’s contractures.

Material, Methods and Results: We retrospectively reviewed sixteen fingers in fifteen patients with severe Dupuytren’s contracture (Tubiana Grade III/IV), operated between April 2000 and July 2005. The mean age was 58 years (27 – 82 years).

All patients underwent an initial application of Orthofix external fixator with pins in the proximal and middle phalanx. The patients were advised to gradually distract the device 3-4 times a day, for two weeks. They were then brought back for removal of fixator and partial fasciectomy with closure of skin by V-Y plasty.

The results were assessed in thirteen patients, as two were lost to follow-up. The mean follow-up period was 30 months (6 – 64 months). The total mean preopera-tive extension deficit improved from 130 degrees to 38 degrees postop.; PIP joint deformity improved from a mean of 77 degrees to 33 degrees postop. and the mean TRAM (Total range of active movements) improved from 108 degrees to 165 degrees.

Functional assessment was done using Michigan Hand Outcome Questionnaire. Overall improvement in hand function was from a preoperative 34% to a postoperative 89%.; aesthetic improvement from a preop. of 46% to a postop of 81% and pain improvement from a preop of 66% to a postop of 96%.

One patient had recurrence, one had features of RSD (Reflex Sympathetic Dystrophy) and one had to undergo amputation due to poor tolerance and persistent infection.

Conclusion: Severe Dupuytren’s contracture is a challenging deformity to deal. The two-stage correction may be considered as an alternative method of treatment in cooperative patients. Our study has shown promising results with good patient satisfaction

We reviewed 13 patients with a complex fracture-dislocation of the proximal interphalangeal joint of a finger and one patient with a complex fracture-dislocation of the interphalangeal joint of thumb. We had treated these injuries using a pins and rubbers traction system which had been modified to avoid friction of the pins against the bone during mobilisation of the joint in order to minimise the risk of osteolysis. A Michigan hand outcome questionnaire was used for subjective assessment. The active range of movement (AROM) of the proximal and distal interphalangeal joints and the grip strength were used for objective assessment.

The mean follow-up was 34 months (12 to 49). The mean normalised Michigan hand outcome score was 84. The mean AROM of the proximal interphalangeal joint was 85° and that of the distal interphalangeal joint 48°. The mean grip strength was 92% of the uninvolved hand.

Twelve patients have returned to their original occupations. There has been no radiological osteolysis or clinical osteomyelitis. This modified traction system has given acceptable results with a low rate of complications. It is light, cheap, effective and easy to apply.

Ten patients, who underwent treatment for complex fracture-dislocation of the proximal interphalangeal joint of finger and one patient for that of the interphalangeal joint of thumb with a modified pins and rubbers traction system, were reviewed to evaluate the clinical and functional results. Two patients had open fracture-dislocation, 5 had pilon fractures and 4 had fracture-dislocations. The system was modified to avoid rotation of the pins in the bone during joint mobilization, thus minimizing the risk of osteolysis due to friction of pins over the bone.

Michigan hand scoring system was used for subjective assessment and range of motion at proximal and distal interphalangeal joints and grip strength for objective assessment. Average follow-up was 18 months (range 3 months to 28 months). The average normalised Michigan hand score was 86. Based on Michigan scores, overall hand function was rated excellent in 8 patients, good in 2 and poor in 1. Eight patients have returned to their original jobs. The average arc of flexion in the proximal interphalangeal joint was 85 degrees and in the distal interphalangeal joint it was 47 degrees. The average grip strength was 95 percent of the uninvolved side. Two patients developed minor pin site infection, which did not necessitate pin removal or any alteration in the treatment regime. There have been no cases of osteolysis, osteitis or osteomyelitis. This modification of pins and rubbers traction system has given very acceptable results with a low complication rate. It is light, cheap, effective and easy to apply.

Open reduction and internal fixation of comminuted, displaced intra-articular or potentially unstable fractures of the distal radius with plate and screws has increasingly become a favoured treatment. Intra-operative assessment of fixation with the help of an image intensifier has always been difficult because of the anatomy of the distal radius which has an average ulnar inclination of 22 degrees and an average volar tilt of 14 degrees. These inclination and tilt produce superimposition of images and imaging of the implants placed as distal as possible to achieve satisfactory fixation often shows the screws to be penetrating the joint.

We describe two new radiographic views of the distal radius, which we used intra-operatively in ten patients undergoing open reduction and internal fixation of distal radius fractures. These are the tangential views of the articular surface of the distal radius taken by elevating the wrist so that the forearm makes an angle to the operating table to negate the effects of natural inclination and tilt in antero-posterior and lateral views. The images were compared with the images of standard antero-posterior and standard lateral views. Screws were thought to have been penetrating the joint in the standard lateral views of all of them and in the standard antero-posterior views of eight of them. However, no screw was seen penetrating the joint in these new views.

The tangential views showed correct relation of the screws with the articular surface and a more distal placement of the plate was possible. This enabled the screws to engage the sub-chondral bone and obtain bi-cortical purchase in presence of dorsal comminution. We recommend use of these views in open reduction and internal fixation of distal radius fractures.