Objectives

Traumatic brachial plexus injury causes severe functional impairment of the arm. Elbow flexion is often affected. Nerve surgery or tendon transfers provide the only means to obtain improved elbow flexion. Unfortunately, the functionality of the arm often remains insufficient. Stem cell therapy could potentially improve muscle strength and avoid muscle-tendon transfer. This pilot study assesses the safety and regenerative potential of autologous bone marrow-derived mononuclear cell injection in partially denervated biceps.

We hypothesised that meniscal tears treated with mesenchymal stem cells (MSCs) together with a conventional suturing technique would show improved healing compared with those treated by a conventional suturing technique alone. In a controlled laboratory study 28 adult pigs (56 knees) underwent meniscal procedures after the creation of a radial incision to represent a tear. Group 1 (n = 9) had a radial meniscal tear which was left untreated. In group 2 (n = 19) the incision was repaired with sutures and fibrin glue and in group 3, the experimental group (n = 28), treatment was by MSCs, suturing and fibrin glue.

At eight weeks, macroscopic examination of group 1 showed no healing in any specimens. In group 2 no healing was found in 12 specimens and incomplete healing in seven. The experimental group 3 had 21 specimens with complete healing, five with incomplete healing and two with no healing. Between the experimental group and each of the control groups this difference was significant (p < 0.001).

The histological and macroscopic findings showed that the repair of meniscal tears in the avascular zone was significantly improved with MSCs, but that the mechanical properties of the healed menisci remained reduced.

The April 2013 Foot & Ankle Roundup³⁶⁰ looks at: whether arthroscopic arthrodesis is advantageous; osteochondral autografts; suture button associated fractures; an ultrasound solution to Achilles tendinopathy; the safety of the tendo Achilles in men; charcot and antibiotic-coated nails; and botox and Policeman’s Heel.

The April 2013 Spine Roundup³⁶⁰ looks at: smuggling spinal implants; local bone graft and PLIF; predicting disability with slipped discs; mortality and spinal surgery; spondyloarthropathy; brachytherapy; and fibrin mesh and BMP.

The belief that an intervertebral disc must degenerate before it can herniate has clinical and medicolegal significance, but lacks scientific validity. We hypothesised that tissue changes in herniated discs differ from those in discs that degenerate without herniation. Tissues were obtained at surgery from 21 herniated discs and 11 non-herniated discs of similar degeneration as assessed by the Pfirrmann grade. Thin sections were graded histologically, and certain features were quantified using immunofluorescence combined with confocal microscopy and image analysis. Herniated and degenerated tissues were compared separately for each tissue type: nucleus, inner annulus and outer annulus.

Herniated tissues showed significantly greater proteoglycan loss (outer annulus), neovascularisation (annulus), innervation (annulus), cellularity/inflammation (annulus) and expression of matrix-degrading enzymes (inner annulus) than degenerated discs. No significant differences were seen in the nucleus tissue from herniated and degenerated discs. Degenerative changes start in the nucleus, so it seems unlikely that advanced degeneration caused herniation in 21 of these 32 discs. On the contrary, specific changes in the annulus can be interpreted as the consequences of herniation, when disruption allows local swelling, proteoglycan loss, and the ingrowth of blood vessels, nerves and inflammatory cells.

In conclusion, it should not be assumed that degenerative changes always precede disc herniation.

Cite this article: Bone Joint J 2013;95-B:1127–33.

We compared the intracompartmental pressures (ICPs) of open and closed tibial fractures with the same injury pattern in a rabbit model. In all, 20 six-month-old New Zealand White male rabbits were used. They were randomised into two equal groups of ten rabbits; an open fracture group (group 1) and a closed fracture group (group 2). Each anaesthetised rabbit was subjected to a standardised fracture of the proximal half of the right tibia using a custom-made device. In order to create a grade II open fracture in group 1, a 10 mm segment of fascia and periosteum was excised. The ICP in the anterior compartment was monitored at six-hourly intervals for 48 hours. Although there was a statistically significant difference in ICP values within each group (both p < 0.001), there was no significant difference between the groups for all measurements (all p ≥ 0.089). In addition, in both groups there was a statistically significant increase in ICP within the first 24 hours, whereas there was a statistically significant decrease within the second 24 hours (p < 0.001 for both groups). We conclude that open tibial fractures should be monitored for the development of acute compartment syndrome to the same extent as closed fractures.

Cite this paper: Bone Joint J 2013;95-B:111–14.

Neurogenic claudication is most frequently observed in patients with degenerative lumbar spinal stenosis. We describe a patient with lumbar epidural varices secondary to obstruction of the inferior vena cava by pathological lymph nodes presenting with this syndrome. Following a diagnosis of follicular lymphoma, successful chemotherapy led to the resolution of the varices and the symptoms of neurogenic claudication.

The lumbar epidural venous plexus may have an important role in the pathogenesis of spinal stenosis. Although rare, epidural venous engorgement can induce neurogenic claudication without spinal stenosis. Further investigations should be directed at identifying an underlying cause.

Soaking bone grafts in a bisphosphonate solution before implantation can prevent their resorption and increase the local bone density in rats and humans. However, recent studies suggest that pre-treatment of allografts with bisphosphonate can prevent bone ingrowth into impaction grafts. We tested the hypothesis that excessive amounts of bisphosphonate would also cause a negative response in less dense grafts. We used a model where non-impacted metaphyseal bone grafts were randomised into three groups with either no bisphosphonate, alendronate followed by rinsing, and alendronate without subsequent rinsing, and inserted into bone chambers in rats. The specimens were evaluated histologically at one week, and by histomorphometry and radiology at four weeks. At four weeks, both bisphosphonate groups showed an increase in the total bone content, increased newly formed bone, and higher radiodensity than the controls. In spite of being implanted in a chamber with a limited opportunity to diffuse, even an excessive amount of bisphosphonate improved the outcome. We suggest that the negative results seen by others could be due to the combination of densely compacted bone and a bisphosphonate.

We suggest that bisphosphonates are likely to have a negative influence where resorption is a prerequisite to create space for new bone ingrowth.

The February 2013 Children’s orthopaedics Roundup³⁶⁰ looks at: the human genome; new RNA; cells, matrix and gene enhancement; the histology of x-rays; THR and VTE in the Danish population; potential therapeutic targets for GCT; optimising vancomycin elution from cement; and how much sleep is enough.

The aim of this study was to determine the effectiveness of antibiotic-impregnated implants in the prevention of bone infection. We used a model of contaminated fracture in goats to evaluate four treatment groups: no treatment, hand-made tobramycin-impregnated polymethylmethacrylate beads, commercially-available tobramycin-impregnated calcium sulphate pellets and commercially-available tobramycin-impregnated polymethylmethacrylate beads. Three weeks after intraosseous inoculation with streptomycin-resistant Staphylococcus aureus tissue cultures showed no evidence of infection in any of the antibiotic-treated groups. All of the cultures were positive in the untreated group. These results show that effective local antibiotic delivery can be obtained with both commercially-available products and with hand-made polymethylmethacrylate beads. The calcium sulphate pellets have the advantage of being bioabsorbable, thereby obviating the need for a second procedure to remove them.

This paper summarises the current knowledge on the effects of medullary reaming of long-bone fractures. Following a review of intramedullary vascular physiology, the consequences for vascularity, the autograft effects, the generation of heat, and fat embolism are outlined. Also, alternative reaming techniques are described.

A rat model of lumbar root constriction with an additional sympathectomy in some animals was used to assess whether the sympathetic nerves influenced radicular pain. Behavioural tests were undertaken before and after the operation.

On the 28th post-operative day, both dorsal root ganglia and the spinal roots of L4 and L5 were removed, frozen and sectioned on a cryostat (8 μm to 10 μm). Immunostaining was then performed with antibodies to tyrosine hydroxylase (TH) according to the Avidin Biotin Complex method. In order to quantify the presence of sympathetic nerve fibres, we counted TH-immunoreactive fibres in the dorsal root ganglia using a light microscope equipped with a micrometer graticule (10 x 10 squares, 500 mm x 500 mm). We counted the squares of the graticule which contained TH-immunoreactive fibres for each of five randomly-selected sections of the dorsal root ganglia.

The root constriction group showed mechanical allodynia and thermal hyperalgesia. In this group, TH-immunoreactive fibres were abundant in the ipsilateral dorsal root ganglia at L5 and L4 compared with the opposite side. In the sympathectomy group, mechanical hypersensitivity was attenuated significantly.

We consider that the sympathetic nervous system plays an important role in the generation of radicular pain.

We have evaluated the effect of the short-term administration of low therapeutic doses of modern COX-2 inhibitors on the healing of fractures.

A total of 40 adult male New Zealand rabbits were divided into five groups. A mid-diaphyseal osteotomy of the right ulna was performed and either normal saline, prednisolone, indometacin, meloxicam or rofecoxib was administered for five days. Radiological, biomechanical and histomorphometric evaluation was performed at six weeks.

In the group in which the highly selective anti-COX-2 agent, rofecoxib, was used the incidence of radiologically-incomplete union was similar to that in the control group. All the biomechanical parameters were statistically significantly lower in both the prednisolone and indometacin (p = 0.01) and in the meloxicam (p = 0.04) groups compared with the control group. Only the fracture load values were found to be statistically significantly lower (p = 0.05) in the rofecoxib group. Histomorphometric parameters were adversely affected in all groups with the specimens of the rofecoxib group showing the least negative effect.

Our findings indicated that the short-term administration of low therapeutic doses of a highly selective COX-2 inhibitor had a minor negative effect on bone healing.

During revision total hip replacement using morcellised compacted bone allograft, 16 patients were randomised to receive a graft which had been rinsed in either an ibandronate solution or in saline. Patients were assessed by dual energy x-ray absorptiometry after operation and at 3, 6, 12 and 24 months. A region of interest between the tip of the femoral stem and the distal plastic plug was chosen to measure the changes in bone density over time. The study was double-blinded. In all the control patients the bone density decreased during the first three months and then remained constant at this lower level. A large proportion of the mass of the bone graft was lost. In contrast, all patients with grafts treated with bisphosphonate showed a slight increase in bone density. The difference between the groups was highly significant at all points in time.

We conclude that rinsing the graft in a bisphosphonate solution prevents its resorption and may therefore reduce the risk of mechanical failure. The treatment is simple, inexpensive, and appears virtually free of risk.

Bisphosphonates reduce peri-prosthetic bone loss in the short term after total hip replacement but the mid- and longer term effects are not known. The aims of this randomised trial were to examine the effect of a single dose of 90 mg of pamidronate on the clinical and radiological outcome and peri-prosthetic bone mineral density in 50 patients (56 hips) over a five-year period, following total hip replacement.

At five years, 37 patients (42 hips) returned for assessment. The Harris hip scores were similar in the pamidronate and placebo groups throughout the study. Also at five years, four patients, two from each group had osteolytic lesions on plain radiography. These were located around the acetabular component in three patients and in the femoral calcar in one. The femoral and acetabular peri-prosthetic bone mineral density in the pamidronate group and the control group was similar at five years.

Pamidronate given as a single post-operative dose does not appear to influence the clinical outcome or prevent the development of osteolytic lesions at five years after total hip replacement.

Objectives

Local corticosteroid infiltration is a common practice of treatment for lateral epicondylitis. In recent studies no statistically significant or clinically relevant results in favour of corticosteroid injections were found. The injection of autologous blood has been reported to be effective for both intermediate and long-term outcomes. It is hypothesised that blood contains growth factors, which induce the healing cascade.

Ciprofloxacin hydrochloride-loaded microspheres were prepared by a spray-drying method using pectin and chitosan. The effects of different polymers and drug ratios were investigated.

The most appropriate carriers were selected by in vitro testing. A rat methicillin-resistant Staphylococcus aureus osteomyelitis model was used to evaluate the effects of the loaded microspheres.

The drug was released rapidly from the pectin carrier but this was more sustained in the chitosan formulation.

Chitosan microspheres loaded with ciprofloxacin hydrochloride were more effective for the treatment of osteomyelitis than equivalent intramuscular antibiotics.

The literature on fracture repair has been reviewed. The traditional concepts of delayed and nonunion have been examined in terms of the phased and balanced anabolic and catabolic responses in bone repair. The role of medical manipulation of these inter-related responses in the fracture healing have been considered.