Thalidomide prolongs survival after experimental musculoskeletal injury, through an effect on mononuclear apoptosis.

BACKGROUND: This study was conducted to investigate the effects of intravenous thalidomide administration in an experimental model of musculoskeletal trauma. We hypothesized that because thalidomide inhibits secretion of tumor necrosis factor alpha (TNF-α), survival of animals that received thalidomide would be significantly prolonged. MATERIAL AND METHODS: After an open fracture of the right femur, 24 rabbits were randomly assigned to control and thalidomide groups. Intravenous therapy with thalidomide was started 30 min after fracture. Hemodynamic monitoring of all animals was performed for 4 h. Survival was recorded and bacterial growth in blood and organs was measured after animal death or sacrifice. Blood was sampled for TNF-α measurement and for isolation of peripheral blood mononuclear cells (PBMCs). Apoptosis of PBMCs was measured by flow cytometry. RESULTS: Survival was significantly prolonged in the thalidomide group. Apoptosis of PBMCs was increased in the control group compared with the thalidomide group at 24 h. There were no differences in vital signs, blood and tissue cultures, and serum TNF-α concentration between the two groups. CONCLUSIONS: Intravenous thalidomide prolonged survival in an experimental model of severe musculoskeletal injury in rabbits. Its mechanism of action did not involve TNF-α suppression but prevention of mononuclear apoptosis. In view of these promising results, further research is needed to clarify the immunomodulatory mechanism of action of thalidomide and its potential use for the management of severe trauma.

Cemented Müller straight stem total hip replacement: 18 year survival, clinical and radiological outcomes.

AIM: To present the 18 year survival and the clinical and radiological outcomes of the Müller straight stem, cemented, total hip arthroplasty (THA). METHODS: Between 1989 and 2007, 176 primary total hip arthroplasties in 164 consecutive patients were performed in our institution by the senior author. All patients received a Müller cemented straight stem and a cemented polyethylene liner. The mean age of the patients was 62 years (45-78). The diagnosis was primary osteoarthritis in 151 hips, dysplasia of the hip in 12 and subcapital fracture of the femur in 13. Following discharge, serial follow-up consisted of clinical evaluation based on the Harris Hip Score and radiological assessment. The survival of the prosthesis using revision for any reason as an end-point was calculated by Kaplan-Meier analysis. RESULTS: Twenty-four (15%) patients died during the follow-up study, 6 (4%) patients were lost, while the remaining 134 patients (141 hips) were followed-up for a mean of 10 years (3-18 years). HSS score at the latest follow-up revealed that 84 hips (59.5%) had excellent results, 30 (22.2%) good, 11 (7.8%) fair and 9 (6.3%) poor. There were 3 acetabular revisions due to aseptic loosening. Six (4.2%) stems were diagnosed as having radiographic definitive loosening; however, only 1 was revised. 30% of the surviving stems showed no radiological changes of radiolucency, while 70% showed some changes. Survival of the prosthesis for any reason was 96% at 10 years and 81% at 18 years. CONCLUSION: The 18 year survival of the Müller straight stem, cemented THA is comparable to those of other successful cemented systems.

Association of NADPH oxidase p22phox gene C242T, A640G and -930A/G polymorphisms with primary knee osteoarthritis in the Greek population.

Osteoarthritis (OA) is the most common form of arthritis with still unknown pathogenic etiology and considerable contribution of genetic factors. Recently, a new emerging role of oxidative stress in the pathology of OA has been reported, lacking however elucidation of the underlying mechanism. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase being a complex enzyme produced by chondrocytes, presents the major source of reactive oxygen species and main contributor of increased oxidative stress. The present study aims to evaluate the association of NADPH oxidase p22phox gene C242T, A640G and -A930G polymorphisms with primary knee OA in the Greek population. One hundred fifty five patients with primary symptomatic knee OA participated in the study along with 139 matched controls. Genotypes were determined using polymerase chain reaction and restriction fragment length polymorphism technique. Allelic and genotypic frequencies were compared between both study groups. NADPH p22phox -A930G polymorphism was significantly associated with knee OA in the crude analysis (P = 0.018). No significant difference was detected for C242T and A640G polymorphisms (P > 0.05). The association between -A930G polymorphism and knee OA disappeared when the results were adjusted for obesity (P = 0.078, odds ratio 0.54, 95 % CI 0.272-1.071). The interaction between all three polymorphisms was not significant. The present study shows that NADPH oxidase p22phox gene C242T, A640G and -A930G polymorphisms are not risk factors for knee OA susceptibility in the Greek population. Further studies are needed to give a global view of the importance of this polymorphism in the pathogenesis of OA.

Risk factors affecting the incidence of infection after orthopaedic surgery: the role of chemoprophylaxis.

The incidence of surgical site infection and urinary tract infection following orthopaedic procedures has diminished in recent years due to modern antimicrobial prophylaxis. We conducted a case-control study (100 cases, 100 controls) in order to evaluate the risk factors associated with infection after orthopaedic procedures. The following risk factors were defined: gender, age, comorbidities [rheumatoid arthritis, diabetes mellitus, obesity (> 30 kg/m2), peripheral vessel disease], pre- and post-operative glucose levels, pre-operative and post-operative length of stay (days), duration (days) of urinary catheterization, type of parenteral antibiotic prophylaxis (cefotaxime or vancomycin), time of surgery (elective or scheduled), American Society of Anesthesiologists (ASA) Score (0-3), type of surgery (fracture osteosynthesis, joint replacement, spinal surgery, other), and the type of anesthesia administered (general, epidural, spinal). Urinary tract infection was the most frequent post-surgical infection (71 out of 100 cases) followed by surgical site infection (15 out of 100 cases). Using the multivariable logistic regression model, we found out that only the type of chemoprophylaxis was statistically significant risk factor (p < 0.001) associated with post-surgical infection. More specifically, the use of vancomycin instead of cephalosporin is associated with a lower risk of infection.

Tibial shaft fracture after removal of an ACE tibial nail.

Intramedullary interlocking nailing is the gold standard method for treatment of tibial shaft fractures. Thus, the growing use of the intramedullary nailing resulted in an increased number of tibial nails removal procedures in daily clinical practice. Despite adequate surgeon experience, the removal of tibial intramedullary nails is not without complications. One of the commonly used nails is the ACE (DePuy Orthopaedics, Inc., Warsaw, IN, USA). The purpose of this paper is to report such a complication following the removal procedure and review the pertinent literature. A 39-year-old female who had sustained a lower-third tibial fracture was treated with an intramedullary nail 5 years ago. Despite her unremarkable follow-up, for personal reasons, a removal procedure was planned. Two undisplaced fractures were observed in the postoperative radiological evaluation. The potential complications of the removal of intramedullary nailing of the tibia should be considered by both physician and patient.

Early increase of serum angiopoietin-2 are associated with early progression to death in experimental injury.

Severe trauma induces systemic inflammatory response syndrome (SIRS) through the release of proinflammatory mediators. Angiopoietin-2 (Ang-2) is over-produced in sepsis and leads to dysfunction of endothelial cells and subsequent multiple organ dysfunction. In order to define the role of Ang-2 in lethal injury, 45 rabbits were studied; eight were administered anesthesia; 11 were sham-operated and 26 were subject to femoral injury. Concentrations of Ang-2, malondialdehyde (MDA), tumor necrosis factor-alpha (TNFα) and endotoxins (LPS) were determined in serum and of Ang-2 in tissues; vital signs and overall survival were recorded. Bacterial growth was quantitatively assessed in liver, spleen and lung of animal that died. Survival of injured animals was shorter than sham operated ones. Serum concentrations of Ang-2 at 4 h was greater among animals where death supervened early, i.e. within 48 h after injury than among rabbits that died later. That was also the case for systolic, diastolic and mean arterial pressures. Serum MDA and TNFα and tissue bacterial growth did not differ between rabbits that died early and rabbits that died late. Serum LPS remained below the limit of detection. These results suggest that circulating Ang-2 participates in the pathogenesis of SIRS after injury connected with early haemodynamic instability.

Serum kinetics of soluble triggering receptor expressed on myeloid cells-1 differs in relation to the type of arthroplasty.

CONTEXT: Soluble triggering receptor expressed on myeloid cells-1 (sTREM-1) participates in the inflammatory process. PURPOSE: To describe changes of sTREM-1 in the serum after hemiarthroplasty (HA) and total hip arthroplasty (THA). METHODS: Serial blood samples were drawn from 122 patients with hip fracture. Interleukin-6 (IL-6), sTREM-1, and C-reactive protein (CRP) were measured. RESULTS: IL-6 and CRP were similarly increased after both HA and THA. sTREM-1 was increased early in HA and late after THA. The only parameter that was higher among patients who developed systemic inflammatory response syndrome was IL-6. CONCLUSIONS: Kinetics of sTREM-1 differs among patients undergoing HA of the hip and those undergoing THA.

Experimental osteomyelitis caused by methicillin-resistant Staphylococcus aureus treated with a polylactide carrier releasing linezolid.

BACKGROUND: The effectiveness of a new delivery system consisting of polymerized dilactide (PLA) with incorporated linezolid was investigated in a rabbit model as a means of treating methicillin-resistant Staphylococcus aureus (MRSA) osteomyelitis. METHODS: The PLA-linezolid system was prepared after thorough stirring of PLA with linezolid at a 10:1 ratio. Experimental osteomyelitis was established in 40 rabbits by a modification of the Norden model with MRSA as the test isolate. After a hole had been drilled in the upper right femur, the isolate was inoculated using a thin needle working as a foreign body. At three weeks, the needle was removed and cultured, and the PLA-linezolid system was implanted in half the animals (group B); the remaining half was the control group (group A). Animals were sacrificed at regular intervals; tissue around the site of implantation was examined for pathologic changes and cultured quantitatively. RESULTS: The prepared system eluted linezolid in vitro at concentrations much greater than the minimum inhibitory concentration (MIC) of the test pathogen for 11 days. At three weeks after inoculation of the test isolate, all animals had osteomyelitis. By the sixth week, bacterial growth from cancellous bone of group B was significantly lower than that in group A. However, this effect was not maintained until the end of the study (weeks 8 and 10), when the differences in bacterial growth in the two groups were not significant. CONCLUSION: Polymerized dilactide mixed with 10% linezolid achieved partial arrest of the offending pathogen in an experimental model of osteomyelitis caused by MRSA.

Finite element method in internal and hybrid external fixation of tibial condylar fractures: a comparative application study.

The treatment of tibial condylar fractures requires the preparation of personalized treatment, customized to the needs of the patient, that will take into consideration his or her personal activities. The purpose of the present study was (1) the development, by using the finite elements method, of a 3-dimensional, highly discrete, simulation model of the knee-tibia, (2) the creation of 6 types of fractures in this model according to Schatzker's classification, (3) the insertion of materials for internal and hybrid external fixation, (4) the recording of the model's biomechanical behavior during the load, and (5) the discovery of findings regarding the stability of the internal and hybrid external treatment methods. The results from the resolution procedure showed that the values of maximum displacements in every fracture type except type III were reduced in the models with internal fixation. This means decreased stiffness and therefore diminished stability of the hybrid external-bone complex in these types of fractures. Internal fixation provides postoperative stability, a basic precondition for accelerated fracture healing.

Kinematic and kinetic analysis of the knee joint before and after a PCL retaining total knee replacement during gait and single step ascent.

The objective of this study was to capture and analyze the kinetics and kinematics and determine the functional performance of the osteoarthritic knee after a posterior cruciate ligament (PCL) retaining total knee arthroplasty. Kinematic and kinetic gait analysis of level walking was performed in 20 subjects (12 female and 8 male) with knee ostoarthritis. These patients were free of any neurological diseases that could affect their normal gait. Mean age was 69.6 ± 6.6 years; mean height was 157.6 cm ± 7.6 cm; and mean weight was 77.2 ± 12.1 kg. Full body gait analyses were performed using the BIOKIN 3D motion analysis system before and 9 months after total knee arthroplasty procedures. Single-step ascending kinetic analyses and plantar pressure distribution analyses were also performed for all subjects. International Knee Society Scores (IKSSs) were also assessed pre- and postoperatively. Significant increases were noted postoperatively in average cadence (preoperative mean = 99.26, postoperative mean = 110.5; p < 0.004), step length (preoperative mean = 0.49, postoperative mean = 0.54; p < 0.01) , and walking velocity (preoperative mean = 0.78, preoperatively, postoperative mean = 0.99; p < 0.001). Decreases in stance duration percentage and knee adduction moment were also reported postoperatively. All patients showed a significant improvement of knee kinetics and kinematics after a PCL retaining total knee arthroplasty. Significant differences were found in the cadence, step length, stride length, and walk velocity postoperatively. IKSSs also significantly improved. Further research is warranted to determine the clinical relevance of these findings.

Unilateral or bilateral V-Y fasciocutaneous flaps for the coverage of soft tissue defects following total knee arthroplasty.

BACKGROUND: Soft tissue necrosis following total knee arthroplasty (TKA) may be the cause of the devastating complication of deep infection. It necessitates an immediate operative intervention because it could potentially jeopardise the arthroplasty or even the limb. METHODS: Sixteen consecutive patients with a mean age of 73,8 years (range 47 to76 years) over a 6-year period (January 2003 to December 2008) with wound dehiscence after TKA were enrolled in the present study. Unilateral or bilateral fasciocutaneous V-Y flaps that are differently oriented, depending on the local conditions of the tissues were used to reconstruct the soft tissues defects. RESULTS: In 15 of the 16 cases studied, the wound was successfully covered with the presented technique while in 1 patient a partial flap loss occurred, which was healed after surgical debridement and the application of vacuum system. No other complications occurred. Knee prosthesis was salvaged in all the patients with a good functional and esthetical outcome. CONCLUSIONS: The presented reconstructive technique is a simple, quick, versatile and reliable solution for the coverage of soft tissue defects following TKA, more than 2 cm width and grade 1 and 2 according to Laing classification, provided the V-Y flaps are applied early in the postoperative period and no complex defects are involved.

Fixation of Mitchell's osteotomy with bioabsorbable pins for treatment of hallux valgus deformity.

We hypothesised that the use of bioabsorbable pins in Mitchell's osteotomy would improve the outcome of patients treated for hallux valgus deformity. A total of 68 patients underwent Mitchell's osteotomy to correct hallux valgus deformity: 33 patients (group A) underwent Mitchell's osteotomy augmented with bioabsorbable pins and 35 patients were treated with the classic operative procedure (group B). Hallux valgus angle (HVA), intermetatarsal angle (IMA), the American Orthopaedic Foot and Ankle Society (AOFAS) hallux metatarsophalangeal-interphalangeal scale and the visual analogue score (VAS) for pain were measured preoperatively and postoperatively. There was no statistically significant difference between the two groups as far as the improvement of the IMA, HVA and AOFAS scale were concerned. Patients of group A had significantly less postoperative pain and returned to their previous activities earlier than patients of group B. The use of the pins did not improve the final outcome of the osteotomy. However, it allowed for faster rehabilitation due to less postoperative pain.

10-year evaluation of the cementless low-contact- stress rotating-platform total knee arthroplasty.

We present the clinical and radiographic outcomes of the cementless low-contact-stress (LCS) rotating-platform total knee arthroplasty. Overall, 423 prostheses were implanted in 393 consecutive patients (30 patients had bilateral total knee replacement) for primary varus gonarthrosis (381 patients) and rheumatoid arthritis (12 patients). There were 81 men and 312 women with a mean age of 73 years (range, 58-85 years). Patella replacement was not performed in any case. Clinical and radiographic evaluation was performed using the Knee Society Score (KSS) and the Knee Society Assessment Form, respectively. The mean follow-up was 10 years (range, 5-15 years). Three patients were lost to follow-up. Survival of the prostheses was 98% at 10 years; three prostheses required revision for deep infection, bearing dislocation, and periprosthetic fracture. The mean KSS improved significantly, from 42 and 44 points preoperatively to 90 and 79 points, respectively, at the latest evaluation (P < 0.001); results were excellent in 278 cases, good in 106, fair in 27, and poor in nine. Radiolucent lines were observed in 80 cases; revision arthroplasty was not performed in any of these cases. Complications included deep infection in one patient, bearing dislocation in one, skin necrosis in four, and a supracondylar fracture in one. The cementless LCS rotating-platform total knee arthroplasty is associated with excellent mid- and long-term results for patients with osteoarthritis and rheumatoid arthritis of the knee.