Aims

Fibrinolysis plays a key transition step from haematoma formation to angiogenesis and fracture healing. Low-magnitude high-frequency vibration (LMHFV) is a non-invasive biophysical modality proven to enhance fibrinolytic factors. This study investigates the effect of LMHFV on fibrinolysis in a clinically relevant animal model to accelerate osteoporotic fracture healing.

Objectives

The treatment of osteoporotic fractures is a major challenge, and the enhancement of healing is critical as a major goal in modern fracture management. Most osteoporotic fractures occur at the metaphyseal bone region but few models exist and the healing is still poorly understood. A systematic review was conducted to identify and analyse the appropriateness of current osteoporotic metaphyseal fracture animal models.

Bone tendon junction (BTJ) healing after injury is often slow, without restoration of fibrocartilage transition zone. Fibrocartilage formation has been observed near articular cartilage. It was hypothesised that articular cartilage interposition could stimulate fibrocartilage transition zone regeneration and improve BTJ healing.

Partial patellectomy repair was performed in goat. Articular cartilage harvested from excised patella segment was interposed between the patella and patellar tendon during repair. No cartilage interposition was used in control group. Samples were harvested at six, 12, and 24 weeks for histological examination (n=6 each). The histological images were digitised and analyzed using an image analysis system. Healing progress was assessed by the amount of new bone formation and fibrocartilage transition zone regeneration. Quantitative data were analyzed using SPSS version 14.0. Statistic al significance level was set at p < 0.05.

There was progressive increase in maximum new bone length and area of new bone formed with time (p< 0.05, Kruskal-Wallis test). No difference was observed between treatment groups. Articular cartilage interposition resulted in more fibrocartilage regeneration and higher proteoglycan uptake at all time points. At 24 weeks, length of fibrocartilage formed measured 7760 ± 629 μm with articular cartilage interposition, compared with 787± 274 μm in control (p = 0.002, Mann-Whitney test). Safranin O length measured 3301 ± 1236 μm with articular cartilage interposition, compared with 277 ± 187 μm in control (p = 0.03, Mann-Whitney test).

Autologous articular cartilage interposition stimulates fibrocartilage transition zone regeneration in BTJ repair without affecting bone formation.

Intra-operative 3-D fluoroscopy has limitations, including low resolution images, little soft tissue information and small working volume. Fusion of 3D data sets (MRI/ CT) had been developed in pre-operative planners. We employed the same principle and developed a new technique of navigation with fused images of pre-operative MRI/CT and intra-operative 3D fluoroscopy.

Pre-op CT/MRI in DICOM was imported to the Stryker Leibinger Spine 3-D and segmentation of the intended bone performed. Patient tracker was mounted and 3-D fluoroscopy performed using Siemens ISO-C 3D. Fusion of CT/MRI with 3D fluoroscopy was performed using “surface matching image correlation” and this automatically registered the bone with MRI/CT. The fused images were then ready for 3D navigation procedures.

Nine patients were included in the series. There were eight fracture cases and seven performed with fused CT and 3-D fluoroscopy (two PCL avulsion fractures, two tibial plateau fractures, one femoral condyle fracture and three pelvic-acetabular fractures). Total of twenty-three screws had been inserted without complication. One tibial plateau fracture fixation and one core decompression for avascular necrosis of femoral head were performed with fused MRI to 3D fluoroscopy.

In conclusion, intra-operative 3-D navigated procedures with fused pre-operative MRI/CT and intra-operative 3-D fluoroscopy were all successful with (1) extended working volume (2) higher resolution images (3) more soft tissue information. We foresee more applications of this new technique in other areas of computer aided surgery

In tibial plateau fracture, anatomical reduction of articular surface with stable fixation can restore the mechanical axis and allow early mobilization. Concomitant management of ligamentous and meniscal injury is essential for preservation of knee function. Open reduction and internal fixation has a significant complication rate.Percutaneous,fluoroscopically and arthroscopically assisted osteosynthesis with special fracture reduction and fixation technique can achieve the purpose of management of tibial plateau fracture, while limiting the soft tissue damage.

18 cases, including all J. Schatzker’s type of tibial plateau fracture, were operated with minimal access surgical technique. Male patients were predominant. The age ranged from 22 to 61 (mean 33.5). Detail pre-operatives planning with CT scan were performed in 16 patients. Fluoroscopy, arthroscopy and special fracture reduction and fixation technique were applied to all cases. All 18 cases could be reviewed. Follow up period ranged from 1 to 4 years (mean 2.3 yr.). Outcome was assessed by HSS Knee Score, standing radiograph and arthroscopy (2 cases).

According to HSS score, 14 patients were rated as excellent (100 to 85), 3 good (84 to 70), 1 fair (69 to 60) and none poor (< 60). Subjectively, 14 patients were satisfied with the treatment. 13 patients were working and participating in sport before injury. 15 took no analgesic, 2 took it once a week and 1 more often. In standing radiograph, only 2 patients showed minimal narrowing of joint space. There was no significant complication directly associated with the procedure.

Percutaneous, fluoroscopically and arthroscopically assisted osteosynthesis is a safe and effective minimal access surgical procedure. Precise pre-operative planning and special fracture reduction and fixation technique are all crucial for success. Short-term clinical outcome is encouraging.