Total disc replacement for chronic discogenic low back pain: a Cochrane review.

Study Design: Systematic literature review.

Objective: To assess the effect of total disc replacement for chronic low back pain due to lumbar degenerative disc disease compared with fusion or other treatment options.

Summary Of Background Data: There is an increasing use in disc replacement devices for degenerative disc disease, but their effectiveness compared with other interventions such as fusion of the motion segment or conservative treatment remains unclear.

Growth factor interactions in bone regeneration.

Bone regeneration is a complex process regulated by a large number of bioactive molecules. Many growth factors and cytokines involved in the natural process of bone healing have been identified and tested as potential therapeutic candidates to enhance the regeneration process. Although many of these studies show an enhancement of the bone regeneration process by a single drug therapy, in vivo bone regeneration is the result of a complex interplay between the applied growth factor and various endogenous produced growth factors.

Goat bone tissue engineering: comparing an intramuscular with a posterolateral lumbar spine location.

The aim of this study was to investigate the effect of implant location on bone formation in goats using autologous bone marrow-derived stromal cells in porous calcium phosphate scaffolds. Intramuscular locations were compared to posterolateral spine fusion locations in eight goats. As scaffolds, we used biphasic calcium phosphate porous blocks of 5 x 5 x 5 mm.

Orthotopic location has limited benefit from allogeneic or autologous multipotent stromal cells seeded on ceramic scaffolds.

Improvement of tissue-engineered grafts is still a challenge in the field of regenerative medicine. Using multipotent stromal cells (MSCs), which have immunosuppressive qualities in an allogeneic situation, off-the-shelf implants can be created. This study compared allogeneic and autologous MSCs at an orthotopic (L1 transverse process model) and ectopic (intramuscular) implantation location in 2-year-old goats.

In vivo matrix production by bone marrow stromal cells seeded on PLGA scaffolds for ligament tissue engineering.

Ligament tissue engineering based on cell-seeded biomechanically functional constructs is a commonly studied strategy toward native anterior cruciate ligament replacement. Little is known about the survival and differentiation of the seeded cells after the transplantation. We applied retroviral genetic marking to trace implanted cells and studied their differentiation by species-specific immunolabeling of the extracellular matrix produced.

Relating cell proliferation to in vivo bone formation in porous Ca/P scaffolds.

Most current methods for cell monitoring on 3D porous scaffolds involve end-stage investigation of scaffolds. Repeated measurements on scaffolds, without disturbing cell vitality and proliferation, are needed to relate in vitro to in vivo data. Alamar Blue was used for this purpose.

No efficacy of silver bone cement in the prevention of methicillin-sensitive Staphylococcal infections in a rabbit contaminated implant bed model.

Data from literature showed that a new type of metallic silver PMMA cement had good results in infection prophylaxis. This study investigated the in vivo efficacy of silver cement in the prevention of methicillin-sensitive Staphylococcal infections, compared to plain and tobramycin-containing cement. In 48 rabbits, 0.

Prophylaxis of infection and effects on osseointegration using a tobramycin-periapatite coating on titanium implants--an experimental study in the rabbit.

No options are available for local antibiotic delivery from uncemented implants. By loading a porous titanium implant with a biomimetic HA-coating (PeriApatite, PA) with antibiotics, we could obtain adequate local antibiotic concentrations and reduce infection susceptibility. This study investigated the efficacy of a tobramycin-loaded PA-coated titanium foam implant in preventing infection, as well as the effects on osseointegration.

The effect of timing of mechanical stimulation on proliferation and differentiation of goat bone marrow stem cells cultured on braided PLGA scaffolds.

Bone marrow stromal cells (BMSCs) have been shown to proliferate and produce matrix when seeded onto braided poly(L-lactide/glycolide) acid (PLGA) scaffolds. Mechanical stimulation may be applied to stimulate tissue formation during ligament tissue engineering. This study describes for the first time the effect of constant load on BMSCs seeded onto a braided PLGA scaffold.

Comparing various off-the-shelf methods for bone tissue engineering in a large-animal ectopic implantation model: bone marrow, allogeneic bone marrow stromal cells, and platelet gel.

Construction of bone grafts for regenerative medicine would highly benefit from off-the-shelf components, such as allogeneic bone marrow stromal cells (BMSCs) and blood-derived growth factors from platelet concentrate. Although allogeneic BMSCs are considered immunosuppressive, their use in transplantation studies is still cautioned. In this study, we used off-the-shelf goat allogeneic BMSCs, per-operatively aspirated bone marrow (BM) and platelet gel (PLG).

In vitro release of antibiotics from commercial PMMA beads and articulating hip spacers.

The efficacy and benefits of high-dose antibiotic cement spacers compared with beads in the treatment of an infected prosthesis have been shown. However, in clinical practice, commercial, low-dose antibiotic bone cement is often used. This study investigated the in vitro antibiotic release of hip spacers made from Refobacin-Palacos-R or Antibiotic-Simplex-P cement compared with Septopal beads.

Traumatic thoracic and lumbar spinal fractures: operative or nonoperative treatment: comparison of two treatment strategies by means of surgeon equipoise.

Study Design: A center parallel cohort study with blinded inclusion based on clinical equipoise.

Objective: To compare outcomes of nonoperative and operative treatment strategies in terms of quality of life and neurologic and functional status.

Summary Of Background Data: Despite a considerable body of literature, sound evidence regarding the optimal treatment for traumatic thoracic and lumbar spine fractures is lacking.

Three-dimensional fiber deposition of cell-laden, viable, patterned constructs for bone tissue printing.

Organ or tissue printing, a novel approach in tissue engineering, creates layered, cell-laden hydrogel scaffolds with a defined three-dimensional (3D) structure and organized cell placement. In applying the concept of tissue printing for the development of vascularized bone grafts, the primary focus lies on combining endothelial progenitors and bone marrow stromal cells (BMSCs). Here we characterize the applicability of 3D fiber deposition with a plotting device, Bioplotter, for the fabrication of spatially organized, cell-laden hydrogel constructs.

The incidence of donor site pain after bone graft harvesting from the posterior iliac crest may be overestimated: a study on spine fracture patients.

Study Design: A retrospective cohort study on patients with traumatic vertebral fractures who underwent fusion with iliac crest bone.

Objective: To evaluate the influence of low back surgery on donor site attributed pain, we compared donor site pain between patients who underwent high and low level fusions.

Summary Of Background Data: The most common complication of posterior iliac crest bone graft harvesting is postoperative pain at the donor site.

Identification of orthopaedic infections using broad-range polymerase chain reaction and reverse line blot hybridization.

Background: Culture remains the gold standard in the diagnosis of bacterial infection, but molecular biological techniques have yielded promising results. In this study, we validated a combined polymerase chain reaction and reverse line blot hybridization protocol for identifying musculoskeletal infections.

Methods: Samples were obtained from seventy-six patients undergoing orthopaedic surgery for various aseptic and septic indications.

The relation between organ anatomy and pre-existent vertebral rotation in the normal spine: magnetic resonance imaging study in humans with situs inversus totalis.

Study Design: In this cross-sectional magnetic resonance imaging study, vertebral rotation was measured in the transverse plane of the normal, nonscoliotic spine of persons with a complete mirror image reversal of the internal body organs, called situs inversus totalis.

Objectives: To determine if a pattern of rotation exists in the normal spine of persons with situs inversus totalis, opposite of what was found in humans with normal organ anatomy.

Summary Of Background Data: In humans, as well as in quadrupeds, the mid and lower thoracic vertebrae of the normal, nonscoliotic spine show a pre-existent pattern of rotation to the right side.

Analysis of ectopic and orthotopic bone formation in cell-based tissue-engineered constructs in goats.

Despite decades of extensive research, the application of cell-based bone tissue engineering in clinically relevant models remains challenging. To improve effectiveness, a better understanding of how the technique should work is crucial. In the current study, we investigated the onset time, rate, location and direction of bone formation in ectopically and orthotopically implanted clinically sized tissue-engineered constructs to gain insight the mechanism behind it.

The effect of cell-based bone tissue engineering in a goat transverse process model.

A disadvantage of traditional posterolateral spinal fusion models is that they are highly inefficient for screening multiple conditions. We developed a multiple-condition model that concentrates on the initial process of bone formation from the transverse process and not on a functional fusion. The effect of bone marrow stromal cells (BMSCs) in four different porous ceramic scaffolds was investigated in this setting.

Cement augmentation techniques in traumatic thoracolumbar spine fractures.

Study Design: Review of human cadaveric and in vivo animal studies and clinical trial.

Objective: To develop less invasive surgical techniques for reconstruction of the anterior column in thoracolumbar fractures.

Summary Of Background Data: Persistent central endplate depression can cause anterior column insufficiency after posterior surgery for traumatic thoracolumbar fractures.

A new in vivo screening model for posterior spinal bone formation: comparison of ten calcium phosphate ceramic material treatments.

This study presents a new screening model for evaluating the influence of multiple conditions on the initial process of bone formation in the posterior lumbar spine of a large animal. This model uses cages designed for placement on the decorticated transverse process of the goat lumbar spine. Five conduction channels per cage, each be defined by a different material treatment, are open to both the underlying bone and overlying soft tissue.

Balloon vertebroplasty in combination with pedicle screw instrumentation: a novel technique to treat thoracic and lumbar burst fractures.

Study Design: Clinical trial (phase II).

Objectives: To assess the feasibility and safety of balloon vertebroplasty after posterior short-segment reduction and fixation for the treatment of traumatic burst fractures.

Summary Of Background Data: Hardware failure and loss of reduction after posterior short-segment instrumentation are complications caused by insufficiency of anterior column support.

Optimization of bone-tissue engineering in goats.

Successful bone-tissue engineering (TE) has been reported for various strategies to combine cells with a porous scaffold. In particular, the period after seeding until implantation of the constructs may vary between hours and several weeks. Differences between these strategies can be reduced to (a) the presence of extracellular matrix, (b) the differentiation status of the cells, and (c) the presence of residual potentially immunogenic serum proteins.

Bone tissue engineering in a critical size defect compared to ectopic implantations in the goat.

Since the application of the autologous bone graft, the need for an alternative has been recognized. Tissue engineering (TE) of bone by combining bone marrow stromal cells (BMSCs) with a porous scaffold, is considered a promising technique. In this study we investigated the potential of tissue engineered bone to heal a critical sized defect in the goat.

Osteogenicity of autologous bone transplants in the goat.

Background: Little is known about the specific mechanisms that make autologous graft bone (AG) superior to the current alternatives. A potential mechanism is the active bone formation by the osteoprogenitor cells within the AG. However, whether these cells survive the transplantation is questionable, especially in nonvascularized, clinically sized grafts.

Optimization of bone tissue engineering in goats: a peroperative seeding method using cryopreserved cells and localized bone formation in calcium phosphate scaffolds.

Background: Bone tissue engineering by combining cultured bone marrow stromal cells with a porous scaffold is a promising alternative for the autologous bone graft. Drawbacks of the technique include the delay necessary for cell culture and the complicated logistics. We investigated methods to bypass these drawbacks.