There has been concern over the safety of the upright position for shoulder surgery from anaesthetists uncomfortable with the risk of reduced cerebral blood flow (CBF). Because there are no studies documenting what happens to CBF during upright surgery we aimed to measure CBF through an indirect and non-invasive method using recently available Ultrasound monitoring equipment.

This study randomised patients into awake (interscalene block alone) and GA with block, and indirectly measured the CBF by using a validated Doppler technique on carotid flow both before and during the shoulder procedure. Non-invasive and invasive measurements of mean arterial pressure were made throughout the procedure, together with doppler measurement of carotid flow following preoperative measurement of carotid contribution to cerebral flow in the radiology department by an experienced sonographer. All measurements recorded in real time and charted independently.

This study has shown that CBF in both groups were consistent with the expected values, and CBF remained proportionate in supine to upright. CBF values in the block alone group were generally lower than the GA group. In the GA group the MAP dropped lower, requiring use of adrenergic drugs to bring the pressure up. Despite the significant drop in MAP, the CBF was still high. This could signify cerebral autoregulation is a significant factor in the upright position.

We have shown the feasibility of use of DOppler to indirectly measure CBF during upright surgery. Despite the predicted drop in MAP in this position with GA, we could NOT show a concurrent drop in CBF, demonstrating that much more complex factors regulate the CBF in these patients. Clearly, monitoring is the key to safe administration of anaesthetic in the upright position.

Platelet-leucocyte gel (PLG), a new biotechnological blood product, has hitherto been used primarily to treat chronic ulcers and to promote soft-tissue and bone regeneration in a wide range of medical fields. In this study, the antimicrobial efficacy of PLG against Staphylococcus aureus (ATCC 25923) was investigated in a rabbit model of osteomyelitis. Autologous PLG was injected into the tibial canal after inoculation with Staph. aureus. The prophylactic efficacy of PLG was evaluated by microbiological, radiological and histological examination. Animal groups included a treatment group that received systemic cefazolin and a control group that received no treatment.

Treatment with PLG or cefazolin significantly reduced radiological and histological severity scores compared to the control group. This result was confirmed by a significant reduction in the infection rate and the number of viable bacteria. Although not comparable to cefazolin, PLG exhibited antimicrobial efficacy in vivo and therefore represents a novel strategy to prevent bone infection in humans.

Purpose: Published series of minimally invasive cervical foraminotomy (MICF) have shown excellent short-term relief of cervical radiculopathy (85–98%) with minimal surgical morbidity. There have been no long-term clinical series documenting the stability of these results over time. This is the first long-term follow-up of MICF patients to determine the incidence of recurrent symptoms and need for additional cervical spine surgery.

Methods: We conducted a multi-center retrospective chart review of 73 patients who had MICF. Clinical outcome measures were assessed from clinic records, operative records, and telephone surveys.

Results: At 3 months, 70/73 patients (96%) reported relief of radicular pain compared to their preoperative state. By 40 months, 15 patients reported symptoms of cervical radiculopathy. 8 patients experienced recurrent symptoms, and the remaining 7 had a new radicular pattern. Of 7 patients with symptoms at new levels, 6 had pre-existing radiographic abnormality. 15 patients underwent additional cervical surgery after MICF. 3 patients underwent repeat MICF at the same level. An additional 2 patients had MICF at a different level. 7 patients had ACDF at the same level and 2 had fusion at a different level. There were no cases of frank instability or spondylolisthesis noted.

Conclusions: At 40 month follow-up, 21% or patients had radicular symptoms with 11% reporting recurrence of preoperative symptoms and 9% with radicular symptoms in a different distribution. 12% (9/73 patients) of the group required ACDF within the follow-up period. Thus, 64/73 patients were spared fusion in this series. Assuming the 2.5% per year incidence of adjacent level fusion cited in the literature, there would have been 6 cases likely to have required another fusion if all 73 patients had been treated with ACDF initially. From this perspective, MICF continues to be our procedure of choice for properly selected patients with cervical radiculopathy.

Background: Aseptic loosening remains the most common cause of failure of total hip arthroplasty. Its pathogenesis is based upon the generation of wear debris particles which trigger synovial macrophage activation.

Statins, inhibitors of 3-hydroxy-3 methylglutaryl coenzyme A (HMG-Co-A) reductase, have revolutionised the treatment of hypercholesterolaemia. More recently statins have been shown to have potent anti inflammatory effects. We investigated the effects of cerivastatin in attenuating the activation of human macrophages by polymethylmethacrylate (PMMA) particles.

Methods: Polymethylmethacrylate-particle-stimulated human macrophages were cultured in vitro with cerivastatin at 75 and 150... mols/litre. TNF-α (tumour necrosis factor alpha) and MCP-1 (monocyte chemotactic protein) expression were determined using ELISA. An ERK1/2 inhibitor, UO126 was utilised to identify the mitogen activated protein kinase (MAP-Kinase) pathway involved and western blotting was used to demonstrate the effect of Cerivastatin on this pathway.

Results PMMA-stimulated TNF-α and MCP-1 expression was consistently attenuated by cerivastatin therapy.

PMMA activation was attenuated by the ERK1/2 inhibitor, UO126.

Western blotting confirmed ERK downregulation by cerivastatin, establishing a mechanism for its anti-inflammatory effects.

Conclusion: We have demonstrated the beneficial effects of statins in suppressing particle mediated activation of macrophages and the potential to prevent or treat periprosthetic osteolysis.

Failure of total hip arthroplasty with acetabular deficiency occurred in 55 patients (60 hips) and was treated with acetabular revision using morsellised allograft and a cemented metal-backed component. A total of 50 patients (55 hips) were available for clinical and radiological evaluation at a mean follow-up of 5.8 years (3 to 9.5). No hip required further revision of the acetabular component because of aseptic loosening.

All the hips except one had complete incorporation of the allograft demonstrated on the radiographs. A complete radiolucent line of > 1 mm was noted in two hips post-operatively. A good to excellent result occurred in 50 hips (91%). With radiological evidence of aseptic loosening of the acetabular component as the end-point, the survivorship at a mean of 5.8 years after surgery was 96.4%.

The use of impacted allograft chips in combination with a cemented metal-backed acetabular component and screw fixation can achieve good medium-term results in patients with acetabular bone deficiency.

Background: Periprosthetic osteolysis precipitates aseptic component loosening, increases periprosthetic fracture risk and through massive bone loss, complicates revision surgery.

Its pathogenesis is based upon the generation of wear debris particles which trigger synovial macrophage activation. Statins, inhibitors of 3-hydroxy-3 methylglutaryl coenzyme A (HMG-Co-A) reductase, have revolutionised the treatment of hypercholesterolaemia and cardiovascular disease. The antiinflammatory properties of HMG-CoA reductase inhihitors or the statin family are well recognised. We investigated the effects of ceriv-astatin in attenuating the activation of human macrophages by polymethylmethacrylate (PMMA) particles.

Methods: Polymethylmethacrylate-particle-stimulated human macrophages were cultured in vitro with cerivastatin at 75 and 150micromols/litre. TNF- alpha (tumour necrosis factor alpha) and MCP-1 (monocyte chemotactic protein) expression were determined using ELISA. UO126, a Raf/MEK/ERK intracellular transduction pathway inhibitor, was utilised to identify the mitogen activated protein kinase (MAP- Kinase) pathway involved and western blotting was used to demonstrate the effect of cerivastatin on this pathway.

Results Human monocyte/macrophage cultures were activated by PMMA particles evidenced by TNF- alpha and MCP-1 expression(p< 0.05). This activation was consistently attenuated by cerivastatin therapy. Similarily, PMMA activation was attenuated by the Raf/MEK/ERK inhibitor, UO126.

Western blotting confirmed Raf/MEK/ERK down-regulation by cerivastatin, establishing a mechanism for its anti-inflammatory effects.

Conclusion We have demonstrated in vitro, that statins can abrogate particle induced inflammatory responses in a dose dependent manner and this is mediated intra-cellularily through its effect on the Raf/MEK/ERK transduction pathway. We propose that by attenuating this inflammatory response, the associated subsequent osteoclast activation and osteolysis is attenuated. Statins therefore may have role in promoting implant longevity

Background Apoptosis of osteoblasts and osteoclasts regulates bone homeostasis. Skeletal injury in humans results in angiogenic responses primarily mediated by vascular endothelial growth factor(VEGF), a protein essential for bone repair in animal models. Osteoblasts release VEGF in response to a number of stimuli and express receptors for VEGF in a differentiation dependent manner. This study investigates the putative role of VEGF in regulating the lifespan of primary human osteoblasts(PHOB) in vitro.

Methods PHOB were examined for VEGF receptors. Cultures were supplemented with VEGF(0–50ng/mL), a neutralising antibody to VEGF, mAB VEGF(0.3ug/mL) and Placental Growth Factor (PlGF), an Flt-1 receptor-specific VEGF ligand(0–100 ng/mL) to examine their effects on mineralised nodule assay, alkaline phosphatase assay and apoptosis.. The role of the VEGF specific antiapoptotic gene target BCl2 in apoptosis was determined.

Results PHOB expressed functional VEGF receptors. VEGF 10 and 25 ng/mL increased nodule formation 2.3- and 3.16-fold and alkaline phosphatase release 2.6 and 4.1-fold respectively while 0.3ug/mL of mAB VEGF resulted in approx 40% reductions in both. PlGF 50ng/mL had greater effects on alkaline phosphatase release (103% increase) than on nodule formation (57% increase). 10ng/mL of VEGF inhibited spontaneous and pathological apoptosis by 83.6% and 71% respectively, while PlGF had no significant effect. Pretreatment with mAB VEGF, in the absence of exogenous VEGF resulted in a significant increase in apoptosis (14 vs 3%). BCl2 transfection gave a 0.9% apoptotic rate. VEGF 10 ng/mL increased BCl2 expression 4 fold while mAB VEGF decreased it by over 50%.

Conclusions VEGF is a potent regulator of osteoblast lifespan in vitro. This autocrine feedback regulates survival of these cells, mediated via the KDR receptor and expression of BCl2 antiapoptotic gene.

Aims: Pharmacological modulation of skeletal muscle reperfusion injury after trauma associated ischaemia may improve limb salvage rates and prevent the associated systemic sequelae. Resuscitation with hypertonic saline restores the circulating volume and has favourable effects on tissue perfusion and blood pressure. The purpose of our study was to evaluate the effects of hypertonic saline on skeletal muscle ischaemia reperfusion (I/R) injury and the associated endorgan injury.

Methods: Adult male Sprague Dawley rats (n=24) were randomised into three groups: control group, I/R group treated with normal saline and I/R group treated with hypertonic saline. Bilateral hind-limb ischaemia was induced by rubber band application proximal to the level of the greater trochanters for 2.5 hours. Treatment groups received either normal saline or hypertonic saline prior to tourniquet release. Following twelve hours reperfusion, the tibialis anterior muscle was dissected and muscle function assessed electrophysiologically by electrical field stimulation. The animals were then sacrificed and skeletal muscle harvested for evaluation. Lung tissue was also harvested for measurement of wet-to-dry ratio, myeloperoxidase content and histological analysis.

Results: Hypertonic saline significantly attenuated skeletal muscle reperfusion injury as shown by reduced twitch and tetanic contractions of the skeletal muscle (Table). There was also a significant reduction in lung injury as demonstrated by differences in wet-to-dry ratio, myeloperoxidase content and histological analysis.

Conclusion: Resuscitation with hypertonic saline may have a protective role in attenuating skeletal muscle ischaemia reperfusion injury and its associated systemic sequelae.

Introduction Structure, position, strength, function and durability are critical following reconstruction after treatment of bone tumours. We aimed to assess performance and make recommendations in relation to shoulder reconstruction.

Methods Shoulder reconstruction following resection of bone tumours of the shoulder girdle was evaluated for thirty-two patients treated from 1987 to 2002. Several kinds of reconstructive procedures were performed and classified according to the system of the Musculoskeletal Tumour Society. Fourteen patients had an osteosarcoma, ten patients had a chondrosarcoma, four patients had an Ewings sarcoma and four had an extensive giant-cell tumour. The choice of reconstruction depended on the type of resection and the needs of the patient. The functional results were assessed and graded quantitatively according to the functional rating system of the Musculoskeletal Tumor Society. The average duration of follow-up was 75 months for the 23 patients who were still alive at the time of the latest follow-up examination.

Results Nine patients died of malignancy (four patients with surgical stage III disease and one with Paget’s osteosarcoma); these patients had an average 18 months follow-up post-operatively. The resection was classified as wide in 27 of 32 patients and as marginal in five. Two patients had local recurrence. Functional results were related to the type of resection and the method of shoulder reconstruction. In patients where the deltoid and rotator cuff could be preserved, allograft-prosthetic composite had better function than prosthesis alone after intra-articular resection of the humerus because reconstruction of the deltoid and the rotator cuff could be performed incorporating the allograft. After intra-articular resection of the proximal humerus with loss of the abductor mechanism, arthrodesis resulted in good function and more strength than was found after reconstruction with prosthesis or allograft-prosthetic composite. A secondary arthrodesis was performed in two patients with symptomatic instability following failed reconstruction with an allograft-prosthetic composite or an osteoarticular allograft. Insertion of an allograft, a vascularized fibular graft, a rotational latissimus dorsi flap and cancellous autograft bone was the preferred arthrodesis technique to achieve fusion as well as to reduce complications. There was one fracture and one infection in 10 patients. After extra-articular resection of the glenoid cavity and the proximal humerus with abductor mechanism, reconstruction with a functional spacer frequently resulted in superior subluxation of the implant and only fair function of the shoulder. With two teen-aged patients, a free fibular graft inserted after intra-articular resection of the proximal humerus led to fair function, to be followed by secondary arthrodesis when growth is complete. After resection of the acromion-glenoid cavity complex in one patient and the entire scapula in a child, no reconstruction resulted in good function of the shoulder.

Conclusions Indications for the method of reconstruction depend on type of resection, age, gender, occupation, the expected functional level and restriction of activity. After resection of the abductor mechanism, arthrodesis resulted in more strength and capacity to position the arm in space. It was suitable for the young. Allograft-prosthetic composite showed better function when the abductor mechanism had been reconstructed. Prostheses should be used in old patients or for palliative surgical treatment after resection the abductor mechanism. The most durable and functional reconstruction was arthrodesis.

Aims: Circulating endothelial precursor cells (CEPs) are thought to play a role in angiogenesis. We investigated the angiogenic stress of musculoskeletal trauma on CEP kinetics in trauma patients and their bone marrow progenitor populations in a murine model. Methods: Peripheral blood mononuclear cells (PB-MNCs) were isolated from patients (n=12) on consecutive days following closed lower-limb diaphyseal fractures. CEP levels, deþned by the surface expression patterns of VEGFR2, CD34 and AC133 were determined and cytokine analysis of collected serum was performed. Bonemarrow precursors deþned byLy-6A/E and c-Kit expression were harvested following the traumatic insult from the murine model and quantiþed on ßow cytometry. Human and murine progenitor populations were cultured on þbronectin and examined for markers of endothelial cell lineage (Ulexeuropaeus- agglutinin-1 binding and acetylated-LDL uptake) and cell morphology. Statistical analysis was performed using variance analysis. Results: A consistent increase in human CEPs levels was noted within 72 hours of the initial insult, the percentage increase over day 1 reaching 300% (p=0.008) and returning to normal levels by day 10. Murine bone marrow precursors were mobilisd within 24 hrs peaking at 48hrs (900% p=0.035). On culture, morphologically characteristic endotheliallike cells binding UEA-1 and incorporating LDL were identiþed. Serum VEGF levels increased signiþcantly within 24 hrs of the insult, (p=0.018) preceeding the peak in CEP mobilisation. Conclusion: We propose that musculoskeletal trauma through the release of chemokines such as VEGF, promotes rapid mobilisation of CEPs from born marrow, which have the potential to contribute to reparative neovascularisation. Strategies to enhance CEPs kinetics may accelerate this process and offer a therapeutic role in aberrant fracture healing.

Background: Circulating endothelial precursor cells (CEPS) are thought to play a role in postnatal angiogenesis. We investigated the angiogenic stress of musculoskeletal trauma on CEP kinetics in trauma patients and their bone marrow progenitor populations in a murine model.

Methods: Peripheral blood mononuclear cells (PB-MNCs) were isolated from patients (n=12) on consecutive days following closed lower-limb diaphyseal fractures. CEP levels, defined by the surface expression patterns of VEGFR2, CD34 and AC133 were determined and cytokine analysis of collected serum was performed. Bone marrow precursors defined by Ly-6A/E and c-Kit expression were harvested following traumatic insult from the murine model and quantified on flow cytometry. Human and murine progenitor populations were cultured on fibronectin and examined for markers of endothelial cell linage (Ulexeuropaeus- agglutinin- 1 binding and acetylated-LDL uptake) and cell morphology. Statistical analysis was performed using variance analysis.

Results: A consistent increase in human CEPs levels was noted within 72 hours of the initial insult, the percentage increase over day 1 reaching 300%.

Conclusion: We propose that musculoskeletal trauma through the release of chemokines such as VEGF, promotes rapid mobilisation of CEP from born marrow, which have the potential to contribute to reparative neovascularisation. Strategies to enhance CEPs kinetics may accelerate this process and offer a therapeutic role in aberrant fracture healing.

An injectable material consisting of calcium sulphate mixed with hydroxyapatite was investigated as a possible alternative to autograft in the restoration of bone defects. The material was studied both in vitro in simulated body fluid (SBF) and in vivo when implanted in rat muscles and into the proximal tibiae of rabbits. Variation in the strength and weight of the material during ageing in SBF was measured. Tissue response, material resorption and bone ingrowth were studied in the animal models.

A good tissue response was observed in both the rat muscles and rabbit tibiae without inflammatory reactions or the presence of fibrous tissue. Ageing in SBF showed that during the first week carbonated hydroxyapatite precipitated on the surfaces of the material and this may enhance bone ingrowth.

We investigated the outcome of deep-vein thrombosis (DVT) in the calf after total knee arthroplasty (TKA) in 48 patients (45 women and three men) by clinical assessment and venographic study between three and four years after surgery. The mean age of the patients was 67.2 ± 7.7 years (52 to 85) and the mean follow-up was 42.6 ± 2.7 months (38 to 48). The diagnosis was osteoarthritis in 47 patients and rheumatoid arthritis in one patient. There were 44 calf thrombi, four popliteal thrombi but no thrombi in the femoral or iliac regions. Of the 48 patients, 24 were clinically symptomatic and 24 were asymptomatic. Clinical examination was carried out on 41 patients, of whom 37 underwent ascending venography. Seven were evaluated by telephone interview.

No patient had the symptoms or signs of recurrent DVT, venous insufficiency in the affected leg, or a history of pulmonary embolism. No patient had been treated for complications of their DVT. Thirty-six of the 37 venographic studies were negative for either old or new DVT in the affected leg. One patient had residual thrombi in the muscular branches of the veins.

Our study shows that deep-vein thromboses in the calf after TKA disappear spontaneously with time. No patient developed a recurrent DVT, proximal propagation or embolisation. Treatment of DVT in the calf after TKA should be based on the severity of the symptoms during the immediate postoperative period.

We have studied 58 patients with pain from osteoporotic vertebral fractures which did not respond to conservative treatment. These were 53 women and five men with a mean age of 72.5 years. They received a nerve-root injection with lidocaine, bupivicaine and DepoMedrol. The mean follow-up period was 13.5 months.

The mean pain scores before treatment, at one and six months after treatment and at the final follow-up were 85, 24.9, 14.1, and 17.4, respectively. According to our modified criteria for grading results, six patients were considered to have an excellent result, 42 good and ten fair. A newly developed compression fracture was noted in three patients. There were no complications related to the injection.

Our study suggests that nerve-root injections are effective in reducing pain in patients with osteoporotic vertebral fractures and that these patients should be considered for this treatment before percutaneous vertebroplasty or operative intervention is attempted.

To determine whether systemic nitric oxide production in tourniquet-induced skeletal muscle ischaemia-reper-fusion injury (SMRI) is dependent on release of vascular endothelial growth factor (VEGF), a modulator of nitric oxide cytoprotection in myocardial ischaemia-reperfusion injury.

Mice were randomised (n=10 per group) into: time controls (no tourniquet) and test animals (bilateral hindlimb tourniquet ischaemia). Blood samples were collected in test animals prior to ischaemia and after reper-fusion. In controls, blood samples were collected at the same corresponding time points. Serum VEGF, nitric oxide metabolites (nitrite and nitrate) and the proinflammatory cytokine tumour necrosis factor (TNF)-α (an indicator of systemic inflammation) were determined. At the end of reperfusion, the lungs and muscle (right gastrocnemius) were harvested and tissue injury determined by measuring myeloperoxidase (MPO) activity, a marker of neutrophil infiltration. Data are presented as mean ± SEM and statistical comparison was performed using one-way analysis of variance (ANOVA) with significance attributed to P < 0.05.

In comparison to control animals, muscle (4.9±0.3 versus 4±0.03 units/g of wet tissue; P=0.02) and lung (16.7±1.9 versus 10.4±0.5; P=0.005) MPO activity at the end of repercussion was significantly greater in test animals. The table shows the results with respect to serum cytokine levels and nitricxide metabolites.

These data demonstrate that SMRI results in local and systemic proinflammatory responses. In contrast to myocardial ischaemia-reperfusion injury, nitric oxide production in tourniquet-induced SMRI is VEGF-independent. Alternative mechanisms for nitric oxide production in tourniquet-controlled extremity surgery requires further evaluation.

Twenty-seven cases of baterial vertebral osteomyelitis during the period Dec. 1986 to Dec. 1995, were analyzed. The ages of the 13 men and 14 women ranged from 23 to 69 years. The main clinical symptoms were lower back pain and a knocking pain, with only 7 patients presenting with fever at the time of admission. Nineteen patients had white cell counts of more than 9000/cumm, and the sedimentation rate was significnatly elevated in 24 of 27 patients. Operation procedures were performed in 19 patients of which 15 patients underwent anterior fusion and bone graft and 4 patients had debridement only. One patient underwent posterior fusion 4 weeks after the anterior debridement with Harrington instrumentation. Other patients underwent bone biopsy under CT guidance and were treated by intravenous antibiotics and bed rest only. Bone union occurred after a period of between 2 months and eleven months. Surgery was indicated if an abscess was present, neurological complications occurred, instability

Pyogenic infection of the spine has been regarded as rare or uncommon. Kuloskil in 1936 reported the earliest large series of 102 cases. It may present diagnostic difficulties, as it often had an insiduous onset. Lower back pain is often ignored, and radiological changes may take weeks or months to develop. Neurological compromise can and does occur when treatment is delayed. Howerver, the increasing use of diagnostic instruments including CT scan and MR imaging has markedly improved the diagnostic rate. From 1986 to 1995 we reviewed 27 cases with proven osteomyelitis of the spine by pathology. This is a report of our experience with clinical presentation, diagnosis and surgical treatment of pyogenic osteomyelitis of the spine.

Introduction: Limb reperfusion in patients following pneumatic tourniquet-controlled surgery is associated with nitric oxide (NO) generation. Meanwhile, NO mediates vascular endothelial growth factor (VEGF)-cytoprotection in myocardial ischaemia-reperfusion injury. In addition, VEGF is contributory in attenuating skeletal muscle ischaemia-reperfusion injury (SMRI). Whether this effect of VEGF is NO-mediated in SMRI is unknown. We investigate whether systemic nitric oxide production in tourniquet-induced SMRI is dependent on VEGF release.

Methods: Anaesthetised male C57BL/6 mice were randomised (n=10 per group) into two groups: time controls (no tourniquet) and test animals with bilateral hindlimb tourniquets (SMRI; 2 hours of ischaemia, 2 hours of reperfusion). Blood samples were collected in test animals prior to ischaemia and after 2 hours of reperfusion. In controls, blood samples were collected at the same corresponding time points. Serum VEGF, nitric oxide metabolites (nitrite and nitrate) and the proinflammatory cytokine tumour necrosis fractor (TNF)-α (an indicator of systemic inflammation) were determined. At the end of reperfusion, the lungs and muscle (right gastrocnemius) were harvested and tissue injury determined by measuring myeloperoxidase (MPO) activity, a marker of neutrophil infiltration. Data are presented as mean ± SEM and statistical comparison was performed using one-way analysis of variance (ANOVA) with significance attributed to P,0.05.

Results: In comparison to control animals, both the muscle (4.9±0.3 versus 4±0.03 units/g of wet tissue; P=0.02) and lung (16.7±1.9 versus 10.4±0.5; P=0.005) MPO activity at the end of reperfusion was significantly greater in test animals.

Conclusions: Our data demonstrates that SMRI results in local and systemic proinflammatory responses. In contrast to myocardial ischaemia-reperfusion injury, nitric oxide production in tourniquet-induced SMRI is VEGF-independent. Alternative mechanisms for nitric oxide production in tourniquet-controlled limb surgery requires further evaluation.

Background: Low molecular weight heparins (LMWH) are of undoubted efficacy as thromboprophylaxis in orthopaedic surgical practice. However, prolonged dosage inhibits bone nodule formation in vitro and we have previously reported that daily dosing significantly delays fracture healing. To further investigate these phenomena we hypothesised that LMWH’s would reduce osteoblast survival and thus bone formation by inducing programmed cell death (apoptosis).

Methods: Primary human osteoblasts were isolated from femoral heads excised during hip arthoplasty and cultured to passage 3–5. These were examined for VEGF receptor expression using a biotinylated binding assay on flow cytometry. Osteoblasts were grown to confluence and then incubated for 24 hours in control medium or medium treated with enoxaparin (200 – 2X10(−4) IU/mL) or combination of enoxaparin (200 – 2X10 (−4) IU/mL) and VEGF (1ng/ml). Apoptosis was determined by measuring cytosolic histone-associated DNA fragmentation using an enzyme linked immunosorbant assay. Results were confirmed by DNA fragmentation analysis on agarose gel electrophoresis. Cell functional viability was measured by a tetrazolium bioreduction colorimetric assay.

Results: Data is expressed as percentage of control apoptosis or viability, illustrates mean ± s.e.m. and n=4 experiments in each case. ANOVA was employed for statistical analysis; *versus control, #versus enoxaparin treated; p< 0.05 was considered significant.

Conclusions: Therapeutic doses of LMWH attenuate osteo-blast survival by inducing significant apoptosis. This effect is partly abrogated by VEGF, which independently enhances osteoblast viability, thus delaying spontaneous and enoxaparin induced apoptosis. These findings may explain the bone resorptive effects of prolonged LMWH therapy and suggest a potential therapeutic role for VEGF in conditions of delayed bone formation.

We operated on 111 patients with 159 congenital club feet with the aim of correcting the deformity and achieving dynamic muscle balance. Clinical and biomechanical assessment was undertaken at least six years after operation when the patient was more than 13 years of age. The mean follow-up was for 11 years 10 months (6 to 36 years).

Good and excellent results were obtained in 91.8%. Patients with normal function of the calf had a better outcome than those with weak calf muscles. The radiological changes were assessed in relation to the clinical outcome. The distribution of pressure under the foot was measured for biomechanical assessment.

Our results support the view that muscle imbalance is an aetiological factor in club foot. Early surgery seems to be preferable. It is suggested that operation should be undertaken as soon as possible after the age of six months, although it may be carried out up to the age of five years. The establishment of dynamic muscle balance appears to be an effective method of maintaining correction. Satisfactory long-term results can be achieved with adequate appearance and function.

We treated 12 patients with multilevel stenosis of the cervical canal after spondylosis or ossification of the posterior longitudinal ligament by an expansive open-door laminoplasty, stabilised by using an anchor system.

The preoperative sagittal diameter of the canal was 9.8 mm(±2.2) which was increased to 16.1 mm (±2.9) after surgery. The mean expansion ratio of the canal was 64% (42 to 100). The anchoring systems did not fail during the follow-up period (mean 29.5 months), and the decompression was maintained. The use of anchor systems to stabilise the posterior elements after laminoplasty is a simple and effective technique for maintaining the increased sagittal diameter of the canal.