The databases of the Picture Archiving and Communication Systems of two hospitals were searched and all children who had a lateral radiograph of the ankle during their attendance at the emergency department were identified. In 227 radiographs, Bohler’s and Gissane’s angles were measured on two separate occasions and by two separate authors to allow calculation of inter- and intra-observer variation. Intraclass correlation coefficients were used to assess the reliability of the measurements.

For Bohler’s angle the overall inter-observer reliability, the intraclass correlation coefficient was 0.90 and the intra-observer reliability 0.95, giving excellent agreement. This reliability was maintained across the age groups. For Gissane’s angle, inter- and intra-observer reliability was only fair or poor across most age groups.

Further analysis of the Bohler’s angle showed a significant variation in the mean angle with age. Contrary to published opinion, the angle is not uniformly lower than that of adults but varies with age, peaking towards the end of the first decade before attaining adult values. The age-related radiologic changes presented here may help in the interpretation of injuries to the hindfoot in children.

We used demineralised bone matrix (DBM) to augment re-attachment of tendon to a metal prosthesis in an in vivo ovine model of reconstruction of the extensor mechanism at the knee. We hypothesised that augmentation of the tendon-implant interface with DBM would enhance the functional and histological outcomes as compared with previously reported control reconstructions without DBM. Function was assessed at six and 12 weeks postoperatively, and histological examination was undertaken at 12 weeks.

A significant increase of 23.5% was observed in functional weight-bearing at six weeks in the DBM-augmented group compared with non-augmented controls (p = 0.004). By 12 weeks augmentation with DBM resulted in regeneration of a more direct-type enthesis, with regions of fibrocartilage, mineralised fibrocartilage and bone. In the controls the interface was predominantly indirect, with the tendon attached to the bone graft-hydroxyapatite base plate by perforating collagen fibres.

Introduction: The aim of the study was to investigate the reproducibility and accuracy of templating total hip arthroplasty with on-screen digital radiographs using three commercially available software packages, and compare the results to templating on-screen using acetates.

Method: In twenty patients undergoing hybrid total hip arthroplasty, pre-operative templating for acetabular size, femoral offset and stem size were performed by three independent observers using on-screen digital radiographs by three different techniques. The magnification of the on-screen images were adjusted appropriately by using a metal coin marker of known size attached to the patient at time of acquiring the radiographs. These images were used to template for total hip arthroplasty using three commercially available digital templating software packages (Orthoview™ Workstation, Southampton, UK, Ferrania LifeWeb TraumaCad™, Berkshire, UK and mdesk™ software suite, RSA Biomedical, Sweden). The templated results were compared with the component sizes subsequently implanted and to templating on-screen using acetates. Intra- and inter-observer reproducibility were assessed using the Intraclass Correlation Coefficient (ICC).

Results: Intra-observer reproducibility was good for the three software systems with almost all ICC values > 0.70. Inter-observer reproducibility was less consistent, which may reflect familiarity and may improve with a “learning curve”. All three software systems tended to slightly undersize the acetabular size.

Discussion: For both reproducibility and accuracy, all the three commercial systems were comparable with templating using the acetate template method. Digital templating using software packages is an acceptable method of templating. Templating software packages are certainly an attractive proposition but until installation & maintenance costs are reduced, “traditional” templating with acetates remains the most effective option.

Recombinant Bone Morphogenetic Protein 7 (OP-1) has been available in the UK since 2001, but there has been little published data on its use in the upper limb. In our institution OP-1 has been used in the management of 23 upper limb patients between 2001–2005, including 10 humeral non-unions. We believe this represents one of the largest single-unit cohorts of humeral fractures treated with OP-1.

We reviewed the 10 humeral patients, who were all tertiary referrals with established non-unions. Two had been treated non-operatively before referral. The remaining eight had undergone a mean of 2.1 operations before OP-1 was used, with autologous bone grafting used in the majority of cases. Surgery occurred at a mean of 70.5 months following initial fracture. Seven patients underwent revision of the fracture fixation, and autologous bone graft was used with the OP-1 in 8 cases. Clinical union was established in 8 patients (80%) within a mean of 7.4 months. Radiological union was achieved in 8 patients (80%) within a mean of 9.1 months. No complications or adverse effects from the use of OP-1 were encountered.

Both cases which failed to unite had a definite history of deep infection prior to index surgery, despite initial treatment with a staged revision procedure before OP-1 use.

This study shows that OP-1 can be used successfully in the treatment of recalcitrant non-unions of the humerus following failure of traditional fracture management methods.

We used an in vivo model to assess the use of an autogenous cancellous bone block and marrow graft for augmenting tendon reattachment to metallic implants. We hypothesised that augmentation of the tendon-implant interface with a bone block would enable retention of the graft on the implant surface, enhance biological integration, and result in more consistent functional outcomes compared with previously reported morcellised graft augmentation techniques.

A significant improvement in functional weight-bearing was observed between six and 12 weeks. The significant increase in ground reaction force through the operated limb between six and 12 weeks was greater than that reported previously with morcellised graft augmented reconstructions. Histological appearance and collagen fibre orientation with bone block augmentation more closely resembled that of an intact enthesis compared with the morcellised grafting technique. Bone block augmentation of tendon-implant interfaces results in more reliable functional and histological outcomes, with a return to pre-operative levels of weight-bearing by 24 weeks.

We examined the mechanical properties of Vicryl (polyglactin 910) mesh in vitro and assessed its use in vivo as a novel biomaterial to attach tendon to a hydroxyapatite-coated metal implant, the interface of which was augmented with autogenous bone and marrow graft. This was compared with tendon re-attachment using a compressive clamp device in an identical animal model. Two- and four-ply sleeves of Vicryl mesh tested to failure under tension reached 5.13% and 28.35% of the normal ovine patellar tendon, respectively. Four-ply sleeves supported gait in an ovine model with 67.05% weight-bearing through the operated limb at 12 weeks, without evidence of mechanical failure.

Mesh fibres were visible at six weeks but had been completely resorbed by 12 weeks, with no evidence of chronic inflammation. The tendon-implant neoenthesis was predominantly an indirect type, with tendon attached to the bone-hydroxyapatite surface by perforating collagen fibres.

In 20 patients undergoing hybrid total hip arthroplasty, the reproducibility and accuracy of templating using digital radiographs were assessed. Digital images were manipulated using either a ten-pence coin as a marker to scale for magnification, or two digital-line methods using computer software. On-screen images were templated with standard acetate templates and compared with templating performed on hard-copy digital prints.

The digital-line methods were the least reliable and accuracy of sizing compared with the inserted prostheses varied between −1.6% and +10.2%. The hard-copy radiographs showed better reproducibility than the ten-pence coin method, but were less accurate with 3.7% undersizing. The ten-pence coin method was the most accurate, with no significant differences for offset or acetabulum, and undersizing of only 0.9%.

On-screen templating of digital radiographs with standard acetate templates is accurate and reproducible if a radiopaque marker such as a ten-pence coin is included when the original radiograph is taken.

We developed an in vivo model of the attachment of a patellar tendon to a metal implant to simulate the reconstruction of an extensor mechanism after replacement of the proximal tibia. In 24 ewes, the patellar tendon was attached to a hydroxyapatite (HA)-coated titanium prosthesis. In 12, the interface was augmented with autograft containing cancellous bone and marrow. In the remaining ewes, the interface was not grafted.

Kinematic gait analysis showed nearly normal function of the joint by 12 weeks. Force-plate assessment showed a significant increase in functional weight-bearing in the grafted animals (p = 0.043). The tendon-implant interface showed that without graft, encapsulation of fibrous tissue occurred. With autograft, a developing tendon-bone-HA-implant interface was observed at six weeks and by 12 weeks a layered tendon-fibrocartilage-bone interface was seen which was similar to a direct-type enthesis.

With stable mechanical fixation, an appropriate bioactive surface and biological augmentation the development of a functional tendon-implant interface can be achieved.