Preoperative antibiotics reduce early surgical site infections after orthopaedic implant removal: a propensity-matched cohort study.

BACKGROUND: Implant removal in orthopaedics after fracture consolidation is a very common procedure but is still associated with a high rate of surgical site infection (SSI). Antibiotic prophylaxis is not recommended but advocated by some. AIM: To assess the efficacy of antibiotic prophylaxis in the prevention of early SSI following orthopaedic implant removal. METHODS: A monocentric retrospective cohort study was conducted. Patients who underwent orthopaedic implant removal procedures performed from 2016 to 2021 were included. A 1:1 propensity score matching function was used to create a cohort with matched baseline characteristics and associated risk factors for SSI. Inter-cohort comparison of the occurrence of SSI (superficial or deep) and revision surgery for SSI, after propensity score matching, was performed using the odds ratio to determine the effect of preoperative antibiotic prophylaxis. FINDINGS: In total, 965 distinct surgical procedures were included. Of these, 69 (7.15%) had an SSI, 24 (35.7%) of which required surgical revision; 214 procedures (22.18%) were performed under preoperative antibiotic prophylaxis. The propensity-matched cohort consisted of 396 procedures (198 with and without antibiotic prophylaxis). The SSI rates were 11.11% and 3.03%, respectively, in the control and antibiotic prophylaxis groups (odds ratio: 0.25; 95% confidence interval: 0.099; 0.63; P = 0.011). No difference was found for revision surgery. CONCLUSION: Preoperative administration of antibiotic prophylaxis considerably reduces the risk of SSI during the removal of an orthopaedic implant without increasing the risk of side-effects.

Wartime upper-extremity injuries in the Sahelian strip: Experience from a French Forward Surgical Team deployed in Mali.

This study aimed to analyze upper-extremity combat-related injuries (CRIs) and non-combat-related injuries (NCRIs) treated in the French Forward Surgical Team currently deployed in Gao, Mali. A retrospective study was conducted using the French Military Health Service OpEX surgical database from February 2013 to March 2020. All patients operated on for upper-extremity injury were included: 224 patients, with a mean age of 28.15 years, for 249 upper-extremity injuries. Seventy-six (33.9%) sustained CRIs and 148 (66.1%) NCRIs. Multiple upper-extremity injuries and associated injuries were significantly more common in the CRI group. The majority of NCRIs involved the hand. Debridement and wound care was the most common procedure in both groups. External fixation and fasciotomy were significantly more frequent in the CRI group, and internal fracture fixation in the NCRI group. The overall number of procedures was significantly higher in the CRI group. Due to the high frequency of upper-extremity injury in current theaters of operations, deployed orthopedic surgeons should be trained in basic hand surgery so as to optimally manage both CRIs and NCRIs.

Blast injury of the hand related to warfare explosive devices: experience from the French Military Health Service.

INTRODUCTION: The objective was to report on the experience of the French Army Health Service in the management of blast injury of the hands related to warfare explosive devices. METHODS: A retrospective study was conducted in the Percy Military Hospital (role 4 medical treatment facility) among French soldiers who presented with a combat-related blast injury of the hand between 2002 and 2018. The functional result was assessed by the disabilities of the arm, shoulder and hand (DASH) and the Orthotics and Prosthetics User Survey (OPUS, upper extremity functional status) scores. Proximal amputations (PAs) and distal amputations (DAs) were distinguished for the analysis. RESULTS: Fifteen patients with a mean age of 31±8 years were included. They totalised 20 blasted hands. There were 16 traumatic amputations: 8 in each of the PA and DA groups. Twelve patients had additional injuries, four of which were polytraumatic. Skin closure time and flap use were higher in the DA group. Only one thumb reconstruction was performed. At a mean follow-up of 6.5±4 years, the number of amputees wearing a prosthesis was higher in the PA group. The mean DASH and OPUS scores were 35.5%±24.0% and 64.0%±19.0%, respectively, with no difference between the two groups. CONCLUSION: The severity of hand blasts related to warfare explosive devices requires the systematic application of damage control surgery. PAs are frequent and secondary reconstruction options are limited. The functional result is poor and similar between proximal and distal amputees.

Metacarpal bone reconstruction by a cementless induced membrane technique.

Gunshot wounds to the hand often produce complex injuries and large segmental bone defects. Bone reconstruction remains a challenge in this context. The induced membrane technique is a simple and effective procedure for reconstruction of segmental bone defects. The technique is straightforward but must be performed rigorously. Usually polymethylmethacrylate (PMMA) cement is required for the first stage of the surgery. We describe four cases of metacarpal bone reconstruction after gunshot wounds in a limited-resource setting. Two patients were treated using the induced membrane technique with a polypropylene syringe body instead of PMMA cement, which was unavailable in this situation. A thick membrane was observed 6 weeks after spacer implantation. Bone union was achieved in all cases.

The state of microsurgical practice in French forward surgical facilities from 2003 to 2015.

Microsurgery is an unusual procedure in the theatres of military operations. We sought to analyze the state of microsurgical practices in the French medical treatment facilities (MTFs) deployed around the world in the 21st century. A retrospective study was conducted among all patients who were operated on in French forward surgical facilities between 2003 and 2015. Those who underwent microsurgical procedures for nerve injury, vascular injury, or extremity reconstruction were included. Only early vascular results were assessed. Among the 2589 patients operated on for an extremity injury during the study period, 56 (2.1%) were included, with the group composed of 29 patients with isolated nerve injuries, 28 patients with nerve and arterial injuries, and two patients with isolated arterial injuries, mostly at the hand level. Nerve procedures predominantly consisted of direct suturing, although autografting and nerve transfers were also performed. Thirteen microvascular repairs were carried out, including nine cases of proximal or digital revascularization; revascularization was successful in six of the nine cases. These procedures were completed by orthopedic surgeons trained in microsurgery, mostly under loupes magnification. Routine nerve repair in the field seems to be specific to French MTFs. Salvage of amputated or devascularized fingers in the combat zone had never been reported before. Such emphasizes the need to train deployed orthopedic surgeons to perform microsurgical procedures and to equip all MTFs with basic microsurgical sets and magnification means.

Surgical Management of Mycetoma in Chad: Experience from the French Forward Surgical Team Deployed in N'Djamena.

Mycetoma is a disease that occurs in the mycetoma belt, between latitudes 15̊ south and 30̊ north. It affects disadvantaged regions with limited access to medical and health facilities. Its general principles of care have changed little and are poorly known. We analyzed the management of mycetoma in Chad by French military surgeons deployed within the Epervier and Barkhane operations. This retrospective descriptive study was conducted among the cohort of Chadian patients managed by the N'Djamena forward surgical team from 2007 to 2018 as part of the medical support to the population. It includes 132 patients who had surgery for mycetoma. Surgical parameters of primary treatment and revisions procedures were analyzed. Postoperative follow-up was at least six months. Amputation was performed in 87/132 (66%) patients. Overall 11 (8.3%) required revision surgery, including 7 (5%) with eumycetoma recurrence. All recurrences occurred in the lower limb. The recurrence rate after excision was 10.2% (5/49) versus 2.3% after amputation (2/87). In the absence of effective and accessible medical treatment, surgery remains the basic treatment for mycetoma. Salvage surgery with local excision should always be considered. However, amputation is the only reliable treatment in cases with late presentation. It should not be proposed too early as limb function is preserved for a long time.

Type III open tibia fractures in low-resources setting. Part 1: strategy and principles of limb salvage.

In developing countries, road traffic accidents result in many cases of open trauma, especially fractures, with the tibia area at particular risk in motorcycle crashes. Despite a high prevalence of severe leg trauma with multi-tissue injuries, few studies have focused on the challenge of their reconstruction in these limited-resource settings. The first part of this review presents the surgical strategy. Limitations and principles of initial limb salvage are detailed. Orthopedic procedures for early damage control, based on debridement and temporary bone stabilization, are often required. The priority is to shorten the time to initial surgical management to avoid infection, which jeopardizes reconstruction.

RIP4 is an ankyrin repeat-containing kinase essential for keratinocyte differentiation.

The epidermis is a stratified, continually renewing epithelium dependent on a balance among cell proliferation, differentiation, and death for homeostasis. In normal epidermis, a mitotically active basal layer gives rise to terminally differentiating keratinocytes that migrate outward and are ultimately sloughed from the skin surface as enucleated squames. Although many proteins are known to function in maintaining epidermal homeostasis, the molecular coordination of these events is poorly understood. RIP4 is a novel RIP (receptor-interacting protein) family kinase with ankyrin repeats cloned from a keratinocyte cDNA library. RIP4 deficiency in mice results in perinatal lethality associated with abnormal epidermal differentiation. The phenotype of RIP4(-/-) mice in part resembles that of mice lacking IKKalpha, a component of a complex that regulates NF-kappaB. Despite the similar keratinocyte defects in RIP4- and IKKalpha-deficient mice, these kinases function in distinct pathways. RIP4 functions cell autonomously within the keratinocyte lineage. Unlike IKKalpha, RIP4-deficient skin fails to fully differentiate when grafted onto a normal host. Instead, abnormal hair follicle development and epidermal dysplasia, indicative of progression into a more pathologic state, are observed. Thus, RIP4 is a critical component of a novel pathway that controls keratinocyte differentiation.

Nerve transfer to biceps to restore elbow flexion and supination in children with obstetrical brachial plexus palsy.

PURPOSE: Nerve transfers to restore elbow flexion have been described for traumatic brachial plexus palsy in adults. Indications are less frequent in infants and the results are less published. METHODS: Ten patients with obstetrical brachial plexus palsy were operated on for lack of flexion against gravity with ulnar or median nerve transfer to biceps motor branch. The primary endpoint was improvement in elbow flexion and supination. RESULTS: Mean age at surgery was 12.5 months and mean follow-up was 2.6 years. The Active Movement Scale (AMS) was used to evaluate elbow flexion and forearm supination. At the last follow-up, the average AMS score improved from 0.3 to 5.7 for elbow flexion and from 0.6 to 5.8 for forearm supination. There was no statistical correlation between the age at surgery and the AMS score 18 months post-operatively. CONCLUSIONS: Nerve transfer to the biceps motor branch can improve elbow flexion and forearm supination in selected patients with upper lesions and can be safely performed until the age of two years.

[Severe leg trauma in a resource-poor environment: indications for amputation in emergencies]. / Traumatismes graves du segment jambier en milieu précaire: place de l'amputation en urgence.

Although the development of multitissue limb reconstruction has reduced the role of post-traumatic primary amputation of the leg, some patients should nonetheless undergo emergency amputations. In developing countries, the socioeconomic context associated with the limited health care supply compromises still further the prognosis of preservation efforts. The decision criteria for surgery are thus different in these settings. The choice of emergency leg amputation or attempted preservation in developing countries depends on the epidemiology of severe leg trauma, the local and general prognosis, and the practice conditions. Three factors must be combined before limb preservation can be attempted: adequate local and general adequate wound elements, an available, experienced surgeon with a competent care structure, and a favorable social context.

Neonatal murine epidermal cells express a functional multidrug-resistant pump.

Phospho-glycoproteins are members of the ABC transporter family encoded by the multidrug-resistant genes. These proteins are highly expressed in many tumor cells derived from patients undergoing treatment with anti-cancer drugs. Phospho-glycoproteins are large 12 transmembrane spanning molecules of 170 kDa, involved in adenosine-5'-triphosphate-dependent efflux of molecules out of the cell, known currently as multidrug-resistant pumps. Expression analysis of phospho-glycoproteins in mice and humans indicates widespread distribution in a number of organs, such as brain and testis. We have analyzed skin, and more particularly keratinocytes, to determine whether they express phospho-glycoproteins and express the multidrug-resistant phenotype. Immunofluorescent staining of skin showed that keratinocytes located in the basal layer of the epidermis preferentially expressed phospho-glycoproteins, as did the outer root sheath cells of hair follicles. Phospho-glycoprotein expression on the basal cells was restricted to the cell surface. Polymerase chain reaction analysis of first strand cDNA from keratinocytes identified the phospho-glycoproteins to be mdr1b. Using beta1 integrin expression and density gradient centrifugation we were able to enrich and identify the basal cell compartment by flow cytometric analysis and assay this subset of cells for phospho-glycoprotein activity. Basal cells loaded with rhodamine 123, a substrate for multidrug-resistant pumps, effluxed the molecule from the cells in a time-dependent manner. This study shows that basal layer keratinocytes express functional phospho-glycoproteins. We speculate that phospho-glycoproteins may play a role in regulating the level of environmental toxins and differentiation factors, as has been suggested for other progenitor cell compartments.

Identification of a new fibroblast growth factor receptor, FGFR5.

A novel fibroblast growth factor receptor (FGFR), designated FGFR5, was identified from an EST database of a murine lymph node stromal cell cDNA library. The EST has approximately 32% identity to the extracellular domain of FGFR1-4. Library screening with this EST identified two full-length alternative transcripts which we designated as FGFR5 beta and FGFR5 gamma. The main difference between these transcripts is that FGFR5 beta contains three extracellular Ig domains whereas FGFR5 gamma contains only two. A unique feature of FGFR5 is that it does not contain an intracellular tyrosine kinase domain. Predictive structural modelling of the extracellular domain of FGFR5 gamma suggested that it was a member of the I-set subgroup of the Ig-superfamily, consistent with the known FGFRs. Northern analysis of mouse and human FGFR5 showed detectable mRNA in a broad range of tissues, including kidney, brain and lung. Genomic sequencing identified four introns but identified no alternative transcripts containing a tyrosine kinase domain. Extracellular regions of FGFR5 beta and 5 gamma were cloned in-frame with the Fc fragment of human IgG(1) to generate recombinant non-membrane bound protein. Recombinant FGFR5 beta Fc and R5 gamma Fc demonstrated specific binding to the ligand FGF-2, but not FGF-7 or EGF. However, biological data suggest that FGF-2 binding to these proteins is with lower affinity than its cognate receptor FGFR2C. The above data indicate that this receptor should be considered as the fifth member of the FGFR family.

Radioimmunoassay of primary bile salts in serum.

Rapid, sensitive radioimmunoassays have been developed for the conjugated primary bile salts, cholate and chenodeoxycholate, using immunogens prepared by the mixed anhydride procedure. Antibodies produced showed equal specificity for glycine and taurine conjugates. Cross-reactivities were comparable with those from other published radioimmunoassays. The assays were routinely performed on unextracted sera and the concentrations correlated well with concentrations determined by gas-liquid chromatography. Accuracy, determined by the addition of bile salt to charcoal-extracted serum, and percision, determined by replicate analysis of a normal sample, were both less than +/- 10%. These figures are comparable with those obtained by both gas-liquid chromatography and other radioimmunoassays for bile salts. Normal sera were found to contain 0.49-1.32 mumol/l of cholate and 0.55-2.02 mumol/l of chenodeoxycholate. Serum concentrations in patients with liver disease were higher than this normal range. Three patients with mild liver distrubance were found to have one bile salt in the upper limit of normal, but in each case the other primary bile salt was outwith the normal range.

Fluctuations of serum bile acid concentrations during the menstrual cycle.

Fasting primary bile acid conjugates were measured in 44 women by radioimmunoassay methods. Bile acid values were significantly greater in the 21 women who were in the first half of the menstrual cycle than in the 23 women in whom blood was sampled during the second half of the cycle. Similar measurements were made at weekly intervals after menstruation in five subjects; increased values were observed in the first week. It is concluded that serum bile acid values fluctuate during the menstrual cycle.

Measurement of serum primary bile acid ratio by gas liquid chromatography and radioimmunoassay.

The application of a sensitive gas liquid chromatography (GLC) assay has enabled patients in different diagnostic groups to be differentiated on the basis of the ratio of the primary bile acids, cholic: chenodeoxycholic acid. Because this method is unsuitable for a routine clinical laboratory, the primary bile acid ratio (PBR) is determined by radioimmunoassay techniques (RIA), and the results were compared with GLC analysis. RIA provided comparable results in control subjects and patients with large-duct obstruction, but significantly higher PBR values were found in cirrhotic subjects.

The estimation of phospholipids in bile.

Total and lipid phosphorus were measured in the duodenal aspirate of 24 fasting subjects following an injection of cholecystokinin. The lipid phosphorus values were lower than the total phosphorus, a difference most pronounced in dilute samples. Storage at -20 degrees C over 4 weeks resulted in a loss of over 50% lipid phosphorus. Such alterations in the lipid phosphorus affected the calculation of biliary phospholipid and hence the saturation index of cholesterol in bile causing it to be erroneously elevated. It is concluded that analysis of bile samples should be undertaken on freshly obtained samples and include a preliminary step for the extraction of lipids.