Compartment syndrome, a devastating consequence of limb trauma, is characterised by severe tissue injury and microvascular perfusion deficits. We hypothesised that leucopenia might provide significant protection against microvascular dysfunction and preserve tissue viability. Using our clinically relevant rat model of compartment syndrome, microvascular perfusion and tissue injury were directly visualised by intravital video microscopy in leucopenic animals. We found that while the tissue perfusion was similar in both groups (38.8% (standard error of the mean (. sem). 7.1). , 36.4. % (. sem. 5.7), 32.0% (. sem. 1.7), and 30.5% (. sem. 5.35) continuously-perfused capillaries at 45, 90, 120 and 180 minutes compartment syndrome, respectively versus 39.2% (. sem. 8.6), 43.5% (. sem. 8.5). , . 36.6% (. sem. 1.4) and 50.8% (. sem. 4.8) at 45, 90, 120 and 180 minutes compartment syndrome, respectively in leucopenia), compartment syndrome-associated muscle injury was significantly decreased in leucopenic animals (7.0% (. sem. 2.0), 7.0%, (. sem. 1.0), 9.0% (. sem. 1.0) and 5.0% (. sem. 2.0) at 45, 90, 120 and 180 minutes of compartment syndrome, respectively in leucopenia group versus 18.0% (. sem. 4.0), 23.0% (. sem. 4.0), 32.0% (. sem. 7.0), and 20.0% (. sem. 5.0) at 45, 90, 120 and 180 minutes of compartment syndrome in control, p = 0.0005). This study demonstrates that the inflammatory process should be considered central to the understanding of the pathogenesis of cellular injury in compartment syndrome. Cite this article: Bone Joint J 2015;97-B:539–43

Aims. Compartment syndrome results from increased intra-compartmental pressure (ICP) causing local tissue ischaemia and cell death, but the systemic effects are not well described. We hypothesised that compartment syndrome would have a profound effect not only on the affected limb, but also on remote organs. Methods. Using a rat model of compartment syndrome, its systemic effects on the viability of hepatocytes and on inflammation and circulation were directly visualised using intravital video microscopy. Results. We found that hepatocellular injury was significantly higher in the compartment syndrome group (192 PI-labelled cells/10. -1 . mm. 3. , standard error of the mean (. sem. ) 51) compared with controls (30 PI-labelled cells/10. -1 . mm. 3. , . sem . 12, p < 0.01). The number of adherent venular white blood cells was significantly higher for the compartment syndrome group (5 leukocytes/30s/10 000 μm. 2. , . sem 1. ) than controls (0.2 leukocytes/30 s/10 000 μm. 2. , . sem . 0.2, p < 0.01). Volumetric blood flow was not significantly different between the two groups, although there was an increase in the heterogeneity of perfusion. Conclusions. Compartment syndrome can be accompanied by severe systemic inflammation and end organ damage. This study provides evidence of the relationship between compartment syndrome in a limb and systemic inflammation and dysfunction in a remote organ. Cite this article: Bone Joint J 2016; 98-B:1132–7

Introduction. The combined incubation of a composite scaffold with bone marrow stromal cells in a perfusion bioreactor could make up a novel hybrid graft material with optimal properties for early fixation of implant to bone. The aim of this study was to create a bioreactor activated graft (BAG) material, which could induce early implant fixation similar to that of allograft. Two porous scaffold materials incubated with cells in a perfusion bioreactor were tested in this study. Methods and Materials. Two groups of 8 skeletally mature female sheep were anaesthetized before aspiration of bone marrow from the iliac crest. For both groups, mononuclear cells were isolated, and injected into a perfusion bioreactor (Millenium Biologix AG, Switzerland). Scaffold granules Ø∼900–1500 μm, ∼88% porosity) in group 1, consisted of hydroxyapatite (HA, 70%) with -tricalcium-phosphate (−TCP, 30%) (Danish Technological Institute, Denmark). The granules were coated with poly-lactic acid (PLA) 12%, in order to increase the mechanical strength of the material (Phusis, France). Scaffold granules Ø∼900–1400 μm, 80% porosity) in group 2 consisted of pure HA/-TCP (Fin Ceramica, Italy). For both groups, cells were incubated in the bioreactor for 2 weeks. Fresh culture medium supplemented with dexamethasone and ascorbic-acid was added every third or fourth day. Porous titanium alloy implants with diameter=length=10mm (Biomet, USA) were inserted bilaterally in each of the distal femurs of the sheep; thus 4 implants in each sheep. The concentric gap (2 mm) surrounding the implant was filled with 1) BAG (autogenous), 2) granules, 3) granules+bone marrow aspirate (BMA, autologous) or 4) allograft. The sheep were euthanized after 6 weeks. Distal femurs were removed and implant-bone samples were divided in two parts. The superficial part was used for mechanical testing and micro-CT scanning, and the profound part for histomorphometry. Push-out tests were performed on an 858 Bionix MTS hydraulic materials testing machine. Shear mechanical properties between implant and newly generated bone were calculated to assess implant fixation. Results were assessed by One-way ANOVA. P-values less than 0.05 were considered significant. Results. One sheep in group 1 had to be euthanized after 4 weeks (excluded). One implant in each group was loosened and could not undergo push-out test (excluded). Group 1: No significant differences regarding failure energy (kJ/m2, p=0.44) or ultimate shear strength (MPa, p=0.17) could be seen. Shear stiffness (MPa) was significantly higher for the allograft group (p=0.04). Group 2: No significant differences regarding failure energy (p=0.11) or shear stiffness (p=0.52) could be seen. Ultimate shear strength was significantly higher for allograft (p=0.04). Results from μ-CT scanning and histomorphometry are pending. Discussion and Conclusion. The present study shows a possible effect of bioreactor activated bone substitute on early implant fixation. We are currently working on bone microarchitecture surrounding implant and histomorphometry. These results will aid in determining if BAG could make up a promising alternative for allograft as bone graft material

Aims

Musculoskeletal infection is a devastating complication in both trauma and elective orthopaedic surgeries that can result in significant morbidity. Aim of this study was to assess the effectiveness and complications of local antibiotic impregnated dissolvable synthetic calcium sulphate beads (Stimulan Rapid Cure) in the hands of different surgeons from multiple centres in surgically managed bone and joint infections.

Objectives. Deep bone and joint infections (DBJI) are directly intertwined with health, demographic change towards an elderly population, and wellbeing. The elderly human population is more prone to acquire infections, and the consequences such as pain, reduced quality of life, morbidity, absence from work and premature retirement due to disability place significant burdens on already strained healthcare systems and societal budgets. DBJIs are less responsive to systemic antibiotics because of poor vascular perfusion in necrotic bone, large bone defects and persistent biofilm-based infection. Emerging bacterial resistance poses a major threat and new innovative treatment modalities are urgently needed to curb its current trajectory. Materials and Methods. We present a new biphasic ceramic bone substitute consisting of hydroxyapatite and calcium sulphate for local antibiotic delivery in combination with bone regeneration. Gentamicin release was measured in four setups: 1) in vitro elution in Ringer’s solution; 2) local elution in patients treated for trochanteric hip fractures or uncemented hip revisions; 3) local elution in patients treated with a bone tumour resection; and 4) local elution in patients treated surgically for chronic corticomedullary osteomyelitis. Results. The release pattern in vitro was comparable with the obtained release in the patient studies. No recurrence was detected in the osteomyelitis group at latest follow-up (minimum 1.5 years). Conclusions. This new biphasic bone substitute containing antibiotics provides safe prevention of bone infections in a range of clinical situations. The in vitro test method predicts the in vivo performance and makes it a reliable tool in the development of future antibiotic-eluting bone-regenerating materials. Cite this article: M. Stravinskas, P. Horstmann, J. Ferguson, W. Hettwer, M. Nilsson, S. Tarasevicius, M. M. Petersen, M. A. McNally, L. Lidgren. Pharmacokinetics of gentamicin eluted from a regenerating bone graft substitute: In vitro and clinical release studies. Bone Joint Res 2016;5:427–435. DOI: 10.1302/2046-3758.59.BJR-2016-0108.R1

Infected non-union after severe open fracture or unsuitable fracture operation is frequently associated with bone defect and its treatment has been controversial. We have used microsurgical vascularised composite graft for these problematic cases. Fifty one patients aged 17∼70 year old (43.6 years old in average), including 41 men and 10 women. Follow-up has been more than 6 months. The vascularised composite graft included a free fibular osteocutaneous flap in 41 cases, a vascular pedicled fibular osteocutaneous flap in 2 cases, a free iliac osteocutaneous flap in 5 cases, a vascularised cutaneous flap in 2 cases and other in one case. All infected non-unions were united without trouble and co-existing infection was successfully eradicated. This method also enables the patients rapid bone union and subsequent early functional recovery. This success was attributed to greater transport of oxygen and good antibiotic perfusion in presence of good blood supply. We conclude that microsurgical vascularised composite graft for infected non-union is an extremely useful method with early bone union and subsidence of infection

We have done emergency vascularized composite graft by microsurgical technique for severe open fractures. It is essential for open injury to cover bones, joints, tendons etc. Vascularized composite graft for open fracture with tissue defect covers bone etc., prevents infection and promotes subsequent early functional recovery. Eighteen patients aged 3–55year old with an average age of 23.1y.o. were treated with this methos. Traffic injuries of leg and foot in children were the most common and others were open severe fracture with tissue defects. The composite graft employed were peroneal osteocutaneous flap, latissimus dolsi flap, parascapular flap and groin flap. The advantage of these flaps to cover the damaged structure primrily facilitatrs rapid tissue repair without infection and scar formation. In fact, except one reoperation due to a skin necrosis in parascapular flap, all grafted flaps successfully repaired the severe damaged bone and joint. Sufficient perfusion of antibiotics by these vascularized flap prevents infection in all cases. Primary emergency vascularized composite graft for severe open fracture with tissue defect is shown to be extremely useful method with rapid repair and functionnal recovery

Introduction. CXC chemokine receptor 4 (CXCR4) is a specific receptor for stromal-derived-factor 1 (SDF-1). SDF-1/CXCR4 interaction contributes to the regulation of endotherial progenitor cell (EPC) recruitment in ischemic tissues. The purpose of this study is to investigate the mechanistic function of CXCR4 on EPCs for bone fracture healing. Materials and methods. We made CXCR4 gene knockout mice using the Cre/loxP system. A reproducible model of femoral fracture was created in both Tie2-Cre CXCR4 knockout mice (CXCR4KO) and wild type mice (control). To evaluate gain function of the SDF-1/CXCR4 pathway, we set three groups of the SDF-1 intraperitoneally injected group, wild type group, and SDF-1 injected CXCR4 KO group. Results. In morphological examinations, relative callus area at week 2 was significantly greater in control group. Real time RT-PCR analysis showed that the gene expressions of angiogenic and osteogenic markers were higher in wild type group. CXCR4KO group represented a significantly lower perfusion value at fracture site than control group. In gain function study, the fracture in the SDF-1 injected group is significantly faster healed. Conclusion. Our results indicated the significance of SDF-1/CXCR4 signal in EPCs to bone fracture healing. This study also suggested that the promotion of CXCR4/SDF-1 signal on EPCs lead to the acceleration of bone fracture healing for new therapeutic strategies to fracture repair

Introduction. Traumatized musculoskeletal tissue often exhibits prolonged time to healing, mostly due to low blood flow and innervation. Intermittent Pneumatic Compression (IPC) increases blood flow and decreases thromboembolic event after orthopedic surgery,[1] however little is known about healing effects.[2] We hypothesized that IPC could stimulate tissue repair: 1.) blood flow 2.) nerve ingrowth 3.) tissue proliferation and during immobilisation enhance 4.) biomechanical tissue properties. Methods. Study 1: In 104 male Sprague Dawley (SD) rats the right Achilles tendon was ruptured and the animals freely mobilized. Half the group received daily IPC-treatment, using a pump and cuff over the hindpaw that inflates/deflates cyclicly, 0–55mmHg (Biopress SystemTM, Flexcell Int.), and the other half received sham-treatment. Healing was assessed at 1,3,6 weeks by perfusion-analysis with laser doppler scanner (Perimed, Sweden), histology and biomechanical testing. Study 2: 48 male SD-rats were ruptured as above. Three groups of each 16 rats were either mobilized, immobilized or immobilized with IPC treatment. Immobilization was performed by plaster cast. Healing was assessed at 2 weeks with histology and biomechanical testing. Results. Study 1: At 3 and 6 weeks reperfusion increased by 21% and 23% (p< 0.05) after IPC-treatment, strengthened by the observation of elevated numbers of blood vessels and nerves. Fibroblast density was at all time points significantly increased in the IPC group. At three and six weeks the IPC treated tendons displayed an increased tissue organization confirmed by higher collagen I/III ratio in the IPC group. No differences (p = 0.10) were found regarding biomechanical strength. Study 2: Compared to mobilization, immobilization caused a downregulation (p<0.05) of all biomechanical and histological parameters, eg. maximum force decreased 80% and collagen III occurrence by 83%. However when immobilization was combined with IPC biomechanical and histological healing increased significantly compared to pure immobilization, eg. maximum force increased 63% and collagen III occurrence by 150%. Conclusion. This study demonstrated that IPC treatment can counteract biomechanical and morphological deficits caused by immobilization by enhancing proliferative soft tissue repair. Thus, IPC promotes tissue repair by stimulating tissue perfusion and nerve ingrowth as well as accelerating both fibroblast proliferation and collagen organization

Aims

Complex fractures of the femur and tibia with associated severe soft tissue injury are often devastating for the individual. The aim of this study was to describe the two-year patient-reported outcomes of patients in a civilian population who sustained a complex fracture of the femur or tibia with a Mangled Extremity Severity Score (MESS) of ≥ 7, whereby the score ranges from 2 (lowest severity) to 11 (highest severity).

Aims

Dual plating of distal femoral fractures with medial and lateral implants has been performed to improve construct mechanics and alignment, in cases where isolated lateral plating would be insufficient. This may potentially compromise vascularity, paradoxically impairing healing. This study investigates effects of single versus dual plating on distal femoral vascularity.

Aims

It has been generally accepted that open fractures require early skeletal stabilization and soft-tissue reconstruction. Traditionally, a standard gauze dressing was applied to open wounds. There has been a recent shift in this paradigm towards negative pressure wound therapy (NPWT). The aim of this study was to compare the clinical outcomes in patients with open tibial fractures receiving standard dressing versus NPWT.

Aims

The aim of this study was to evaluate near-infrared spectroscopy (NIRS) as a continuous, non-invasive monitor for acute compartment syndrome (ACS).

There have been many advances in the resuscitation and early management of patients with severe injuries during the last decade. These have come about as a result of the reorganisation of civilian trauma services in countries such as Germany, Australia and the United States, where the development of trauma systems has allowed a concentration of expertise and research. The continuing conflicts in the Middle East have also generated a significant increase in expertise in the management of severe injuries, and soldiers now survive injuries that would have been fatal in previous wars. This military experience is being translated into civilian practice.

The aim of this paper is to give orthopaedic surgeons a practical, evidence-based guide to the current management of patients with severe, multiple injuries. It must be emphasised that this depends upon the expertise, experience and facilities available within the local health-care system, and that the proposed guidelines will inevitably have to be adapted to suit the local resources.

We present the results of 13 patients who suffered severe injuries to the lower leg. Five sustained a traumatic amputation and eight a Gustilo-Anderson type IIIC open fracture. All were treated with debridement, acute shortening and stabilisation of the fracture and vascular reconstruction. Further treatment involved restoration of tibial length by callus distraction through the distal or proximal metaphysis, which was commenced soon after the soft tissues had healed (n = 8) or delayed until union of the fracture (n = 5).

All patients were male with a mean age of 28.4 years (17 to 44), and had sustained injury to the leg only. Chen grade II functional status was achieved in all patients. Although the number of patients treated with each strategy was limited, there was no obvious disadvantage in the early lengthening programme, which was completed more quickly.

Between 2000 and 2006 we performed salvage tibiotalar arthrodesis in 17 diabetic patients (17 ankles) with grossly unstable ankles caused by bimalleolar fractures complicated by Charcot neuro-arthropathy. There were ten women and seven men with a mean age of 61.6 years (57 to 69). A crossed-screw technique was used. Two screws were used in eight patients and three screws in nine. Additional graft from the malleoli was used in all patients. The mean follow-up was 26 months (12 to 48) and the mean time to union was 5.8 months (4 to 8). A stable ankle was achieved in 14 patients (82.4%), nine of whom had bony fusion and five had a stiff fibrous union. The results were significantly better in underweight patients, in those in whom surgery had been performed three to six months after the onset of acute Charcot arthropathy, in those who had received anti-resorptive medication during the acute stage, in those without extensive peripheral neuropathy, and in those with adequate peripheral oxygen saturation (> 95%). The arthrodesis failed because of avascular necrosis of the talus in only three patients (17.6%), who developed grossly unstable, ulcerated hindfeet, and required below-knee amputation.

The aim of this study was to report the pattern of severe open diaphyseal tibial fractures sustained by military personnel, and their orthopaedic–plastic surgical management.The United Kingdom Military Trauma Registry was searched for all such fractures sustained between 2006 and 2010. Data were gathered on demographics, injury, management and preliminary outcome, with 49 patients with 57 severe open tibial fractures identified for in-depth study. The median total number of orthopaedic and plastic surgical procedures per limb was three (2 to 8). Follow-up for 12 months was complete in 52 tibiae (91%), and half the fractures (n = 26) either had united or in the opinion of the treating surgeon were progressing towards union. The relationship between healing without further intervention was examined for multiple variables. Neither the New Injury Severity Score, the method of internal fixation, the requirement for vascularised soft-tissue cover nor the degree of bone loss was associated with poor bony healing. Infection occurred in 12 of 52 tibiae (23%) and was associated with poor bony healing (p = 0.008). This series characterises the complex orthopaedic–plastic surgical management of severe open tibial fractures sustained in combat and defines the importance of aggressive prevention of infection.

Cite this article: Bone Joint J 2013;95-B:101–5.

We treated 47 patients with a mean age of 57 years (22 to 88) who had a proximal humeral fracture in which there was a severe varus deformity, using a standard operative protocol of anatomical reduction, fixation with a locking plate and supplementation by structural allografts in unstable fractures. The functional and radiological outcomes were reviewed.

At two years after operation the median Constant score was 86 points and the median Disabilities of the Arm, Shoulder and Hand score 17 points. Seven of the patients underwent further surgery, two for failure of fixation, three for dysfunction of the rotator cuff, and two for shoulder stiffness. The two cases of failure of fixation were attributable to violation of the operative protocol. In the 46 patients who retained their humeral head, all the fractures healed within the first year, with no sign of collapse or narrowing of the joint space. Longer follow-up will be required to confirm whether these initially satisfactory results are maintained.

A series of 26 children was referred to our specialist unit with a ‘pink pulseless hand’ following a supracondylar fracture of the distal humerus after a mean period of three months (4 days to 12 months) except for one referred after almost three years. They were followed up for a mean of 15.5 years (4 to 26). The neurovascular injuries and resulting impairment in function and salvage procedures were recorded. The mean age at presentation was 8.6 years (2 to 12). There were eight girls and 18 boys.

Only four of the 26 patients had undergone immediate surgical exploration before referral and three of these four had a satisfactory outcome. In one child the brachial artery had been explored unsuccessfully at 48 hours. As a result 23 of the 26 children presented with established ischaemic contracture of the forearm and hand. Two responded to conservative stretching. In the remaining 21 the antecubital fossa was explored. The aim of surgery was to try to improve the function of the hand and forearm, to assess nerve, vessel and muscle damage, to relieve entrapment and to minimise future disturbance of growth.

Based on our results we recommend urgent exploration of the vessels and nerves in a child with a ‘pink pulseless hand’, not relieved by reduction of a supracondylar fracture of the distal humerus and presenting with persistent and increasing pain suggestive of a deepening nerve lesion and critical ischaemia.

The surgical treatment of three- and four-part fractures of the proximal humerus in osteoporotic bone is difficult and there is no consensus as to which technique leads to the best outcome in elderly patients. Between 1998 and 2004 we treated 76 patients aged over 70 years with three- or four-part fractures by percutaneous reduction and internal fixation using the Humerusblock.

A displacement of the tuberosity of > 5 mm and an angulation of > 30° of the head fragment were the indications for surgery.

Of the patients 50 (51 fractures) were available for follow-up after a mean of 33.8 months (5.8 to 81). The absolute, age-related and side-related Constant scores were recorded. Of the 51 fractures, 46 (90.2%) healed primarily. Re-displacement of fragments or migration of Kirschner wires was seen in five cases. Necrosis of the humeral head developed in four patients. In three patients a secondary arthroplasty had to be performed, in two because of re-displacement and in one for necrosis of the head. There was one case of deep infection which required a further operation and one of delayed healing.

The mean Constant score of the patients with a three-part fracture was 61.2 points (35 to 87) which was 84.9% of the score for the non-injured arm. In four-part fractures it was 49.5 points (18 to 87) or 68.5% of the score for the non-injured arm.

The Humerusblock technique can provide a comfortable and mobile shoulder in elderly patients and is a satisfactory alternative to replacement and traditional techniques of internal fixation.