Objectives

The objective of this study was to determine if the use of fascia lata as a tendon regeneration guide (placed into the tendon canal following harvesting the semitendinosus tendon) would improve the incidence of tissue regeneration and prevent fatty degeneration of the semitendinosus muscle.

Objective

We reviewed clinical results with minimally invasive method and using a new developed plate for unstable pelvic ring fractures, especially vertically unstable sacral fractures.

Objectives

The purpose of this study was to evaluate chronological changes in the collagen-type composition at tendon–bone interface during tendon–bone healing and to clarify the continuity between Sharpey-like fibres and inner fibres of the tendon.

We have been operating TKA for the deformity of OA and RA knee using OrthoPilot kinematic navigation system manufactured by Aesculap (Germany, Tutulingen) since 2005. It has the technology of ligament balance check capability, of which intra-operative registration is not so troublesome and also has the guidance system to achieve the correct bony cutting to the mechanical axis. Although we only have short-term results so far, we have evaluated our results and made some observations.

We have 151 cases at our institution composed of 114 OAs and 37 RAs, with 29 males and 122 females. Among them, 95 cases were able to follow-up over one year.

Limited only to three cases, we had to discontinue the usage of this system due to the loosening of the rigid body during surgery, which we had to change the maneuver to use manual instrument.

The average age at the time of surgery was 73.8 years (range, 38 to 90), and the average BMI was 24.5 (range, 15.6 to 37.7). The average femoral axis, which is the angle between the femoral mechanical axis and the femoral joint surface in the coronal plane, was 2.06 degrees (range, −9 to 10). The average pre-bone-cutting tibiofemoral axis was −8.04 degrees (range, −31 to 15), which after implantation became −0.18 degrees (range, −6 to 6). Tibial proximal cutting has to be perpendicular to the mechanical axis of the lower leg in the coronal plane. The average tibial medial cut was 1.61mm (range, 8 to −11) and tibial lateral cut was 6.78mm (range, 15 to −2). This difference of about 5mm indicates that the shape of tibia had varus deformity to the mechanical axis of the lower leg. On the femoral side, the average femoral medial cut was 9.72mm (range, 19 to 1) and femoral lateral cut was 8.23mm (range, 16 to 1). This almost identical cutting thickness indicates that there was almost no deformity to the mechanical axis on the femoral side. The final X-ray in the follow up period had not changed from the post-operative one. There was no change in VAS comparison three months post-operative.

The results of this study seem to indicate that the kinematic navigation system for TKA will lead to good results of patients’ satisfaction and long durability even for OA and RA knees.

We studied bone-tendon healing using immunohistochemical methods in a rabbit model.

Reconstruction of the anterior cruciate ligament was undertaken using semitendinosus tendon in 20 rabbits. Immunohistochemical evaluations were performed at one, two, four and eight weeks after the operation. The expression of CD31, RAM-11, VEGF, b-FGF, S-100 protein and collagen I, II and III in the bone-tendon interface was very similar to that in the endochondral ossification. Some of the type-III collagen in the outer layer of the graft, which was deposited at a very early phase after the operation, was believed to have matured into Sharpey-like fibres. However, remodelling of the tendon grafted into the bone tunnel was significantly delayed when compared with this ossification process. To promote healing, we believe that it is necessary to accelerate remodelling of the tendon, simultaneously with the augmentation of the ossification.

Purpose: Extruded tissue specimens excised during surgery on human intervertebral disc hernia and chondrocytes established and cultured from the excised tissue were observed via electron microscopy. Macrophages confirmed by CD68 immunostaining were added to the chondrocyte culture, and observed via electron microscopy. To observe, using an electron microscope, disc hernia degeneration at the cellular level as expressed in extruded tissue from a human intervertebral disc and cultured chondrocytes, and to investigate the mechanism of spontaneous regression and the effects of macrophages.

Materials and Methods: Tissues excised during surgery were fixed in various fixatives for electron microscopy and immune electron microscopy to avoid divided and treated with collagenase, and chondrocytes were then isolated and cultured. Human heparinized peripheral blood was separated using Ficoll and cultured. After culture, macrophages were collected and confirmed by CD68 immunostaining. These macrophages were added to the chondrocyte culture and observed under an electron microscope.

Results: Chondrocytes in the hernia is extruded region markedly differed from cultured chondrocytes. The tissue extruded from the intervertebral disc showed obvious degeneration such as changes in osmotic pressure. Macrophages were observed as the mechanism of spontaneous regression.

Discussion: In a previous study, we used ELISA to measure MMP-3 levels and TIMP-1 levels in both mRNA and serum in patients, and found a correlation between the two. In this study, we observed the pathological state of a disc hernia at the cellular level. When chondrocytes from the same tissue were cultured under conditions similar to those in the intervertebral disc, the extruded tissue showed a clear difference. It was considered that membrane osmotic pressure affects intervertebral disc hernia in humans and that protein transmission occurs in endoplasmic reticulum. It was also considered that spontaneous regression is due to the infiltration of macrophages.

Sterilisation by gamma irradiation in the presence of air causes free radicals generated in polyethylene (PE) to react with oxygen, which could lead to loss of physical properties and reduction in fatigue strength. Tissue retrieved from failed total hip replacements often has large quantities of particulate PE and most particles associated with peri-implant osteolysis are oxidised. Consequently, an understanding of the cellular responses of oxidised PE particles may lead to clarification of the pathogenesis of osteolysis and aseptic loosening.

We have used the agarose system to demonstrate the differential effects of oxidised and non-oxidised PE particles on the release of proinflammatory products such as interleukin-1β (IL-1β), IL-6, and tumour necrosis factor-α (TNF-α) from monocytes/ macrophages (M/M). Oxidised PE particles were shown to stimulate human M/M to phagocytose and to release cytokines. Oxidation may alter the surface chemistry of the particles and enhance the response to specific membrane receptors on macrophages, such as scavenger-type receptors.

We assessed the unloading effect of the patellar tendon-bearing (PTB) cast in five healthy volunteers using a new system for analysis of dynamic plantar pressure. We devised a method to improve the unloading effect of the PTB cast, and tested this using the same system.

Our findings showed that the conventional PTB cast only achieved unloading of 30% of the body-weight and that the part of the cast on the leg had a more important role in the unloading than that which was in contact with the patellar tendon. When the depth of the free space under the foot inside the PTB cast was 1, 2 and 3 cm, the unloading effect was 60%, 80% and 98%, respectively.

The unloading effect of the conventional PTB cast was disappointing at only 30% of body-weight. It was improved by producing a space between the sole of the foot and the cast, and was adjustable by altering the depth of this space.