Resistant fabric warming is a viable alternative to forced-air warming to prevent inadvertent perioperative hypothermia during hemiarthroplasty in the elderly.

BACKGROUND: Surgical site infection (SSI) is associated with inadvertent perioperative hypothermia (IPH). This can be prevented by active patient warming. However, results from comparisons of warming techniques are conflicting. They are based mostly on elective surgery, are from small numbers of patients, and are dominated by the market leader, forced-air warming (FAW). Furthermore, the definition of hypothermia is debatable and systematic reviews of warming systems conclude that a stricter control of temperature is required to study the benefits of warming. AIM: To analyse core temperatures in detail in a large subset of elderly patients who took part in a randomized trial of patient warming following hemiarthroplasty who had received constant zero-flux thermometry to record their temperature. METHODS: Regression models with a fixed effect for warming group and covariates related to temperature were compared for 257 participants randomized to FAW or resistant fabric warming (RFW) from a prior clinical trial. FINDINGS: Those in the RFW group were -0.08°C cooler and had a cumulative hypothermia score -1.87 lower than those in the FAW group. There was no difference in the proportion of hypothermic patients at either <36.5°C or <36.0°C. CONCLUSIONS: This is the first study to provide accurate temperature measurements in patients undergoing a procedure predominantly under regional rather than general anaesthetic. It shows that RFW is a viable alternative to FAW for preventing IPH during hemiarthroplasty. Further studies are needed to measure the benefits of patient warming in terms of clinically important outcomes.

Reducing Implant Infection in Orthopaedics (RIIiO): Results of a pilot study comparing the influence of forced air and resistive fabric warming technologies on postoperative infections following orthopaedic implant surgery.

BACKGROUND: Active warming during surgery prevents perioperative hypothermia but the effectiveness and postoperative infection rates may differ between warming technologies. AIM: To establish the recruitment and data management strategies needed for a full trial comparing postoperative infection rates associated with forced air warming (FAW) versus resistive fabric warming (RFW) in patients aged >65 years undergoing hemiarthroplasty following fractured neck of femur. METHODS: Participants were randomized 1:1 in permuted blocks to FAW or RFW. Hypothermia was defined as a temperature of <36°C at the end of surgery. Primary outcomes were the number of participants recruited and the number with definitive deep surgical site infections. FINDINGS: A total of 515 participants were randomized at six sites over a period of 18 months. Follow-up was completed for 70.1%. Thirty-seven participants were hypothermic (7.5% in the FAW group; 9.7% in the RFW group). The mean temperatures before anaesthesia and at the end of surgery were similar. For the primary clinical outcome, there were four deep surgical site infections in the FAW group and three in the RFW group. All participants who developed a postoperative infection had antibiotic prophylaxis, a cemented prosthesis, and were operated under laminar airflow; none was hypothermic. There were no serious adverse events related to warming. CONCLUSION: Surgical site infections were identified in both groups. Progression from the pilot to the full trial is possible but will need to take account of the high attrition rate.

Correlation of histological and microbiological findings in septic and aseptic knee implant failure.

INTRODUCTION: The Musculoskeletal Infection Society (MSIS) has defined specific clinical and laboratory criteria for the diagnosis of periprosthetic joint infection (PJI). In this study we assessed the diagnostic utility of MSIS microbiological and histological criteria for PJI in 138 cases of septic and aseptic knee implant failure. MATERIALS AND METHODS: Intra-operative samples from 60 cases of knee septic implant failure (SIF) and 78 cases of aseptic implant failure (AIF), defined on the basis of clinical, laboratory and operative findings/surgical management, were analysed microbiologically and histologically. Findings were correlated with the final clinical diagnosis and the specificity, sensitivity, accuracy, positive and negative predictive value of MSIS microbiological and histological criteria for knee PJI were assessed. RESULTS: 80% of SIF cases showed culture of the same organism from two or more samples (ie MSIS microbiological criteria for definite PJI); 8.3% grew an organism from one sample, and 11.7% showed no growth from any sample. 23.1% of AIF cases grew an organism from one sample and 76.9% showed no growth from any sample. MSIS histological criteria for PJI identified 96.7% of SIF cases. The sensitivity, specificity, accuracy and positive and negative predictive value of MSIS histological criteria for PJI were 96.7%, 100%, 98.6%, 100% and 97.5%, respectively. MSIS microbiological and histological criteria identified all AIF cases. CONCLUSIONS: Knee PJI is more often identified by current MSIS histological than microbiological criteria. A significant proportion of SIF cases show either no growth or growth of an organism from only one sample. AIF is identified by both MSIS microbiological and histological criteria. Correlation of clinical, radiological and laboratory findings is required for the diagnosis of knee PJI.

The role of histology in the diagnosis of spondylodiscitis: correlation with clinical and microbiological findings.

AIMS: The aim of this study was to determine the diagnostic utility of histological analysis in spinal biopsies for spondylodiscitis (SD). PATIENTS AND METHODS: Clinical features, radiology, results of microbiology, histology, and laboratory investigations in 50 suspected SD patients were evaluated. In 29 patients, the final (i.e. treatment-based) diagnosis was pyogenic SD; in seven patients, the final diagnosis was mycobacterial SD. In pyogenic SD, the neutrophil polymorph (NP) infiltrate was scored semi-quantitatively by determining the mean number of NPs per (×400) high-power field (HPF). RESULTS: Of the 29 pyogenic SD patients, 17 had positive microbiology and 21 positive histology (i.e. one or more NPs per HPF on average). All non-SD patients showed less than one NP per HPF. The presence of one or more NPs per HPF had a diagnostic sensitivity of 72.4%, specificity 100%, accuracy 100%, positive predictive value (PPV) 81.0%, and negative predictive value (NPV) 61.9%. Sensitivity, specificity, and accuracy were greater using the criterion of positive histology and/or microbiology than positive histology or microbiology alone. Granulomas were identified histologically in seven mycobacterial SD patients, and positive microbiology was detected in four. CONCLUSION: The diagnosis of pyogenic SD was more often confirmed by positive histology (one or more NPs per HPF on average) than by microbiology, although diagnostic sensitivity was greater when both histology and microbiology were positive. Cite this article: Bone Joint J 2019;101-B:246-252.

Fracture-related infection: A consensus on definition from an international expert group.

Fracture-related infection (FRI) is a common and serious complication in trauma surgery. Accurately estimating the impact of this complication has been hampered by the lack of a clear definition. The absence of a working definition of FRI renders existing studies difficult to evaluate or compare. In order to address this issue, an expert group comprised of a number of scientific and medical organizations has been convened, with the support of the AO Foundation, in order to develop a consensus definition. The process that led to this proposed definition started with a systematic literature review, which revealed that the majority of randomized controlled trials in fracture care do not use a standardized definition of FRI. In response to this conclusion, an international survey on the need for and key components of a definition of FRI was distributed amongst all registered AOTrauma users. Approximately 90% of the more than 2000 surgeons who responded suggested that a definition of FRI is required. As a final step, a consensus meeting was held with an expert panel. The outcome of this process led to a consensus definition of FRI. Two levels of certainty around diagnostic features were defined. Criteria could be confirmatory (infection definitely present) or suggestive. Four confirmatory criteria were defined: Fistula, sinus or wound breakdown; Purulent drainage from the wound or presence of pus during surgery; Phenotypically indistinguishable pathogens identified by culture from at least two separate deep tissue/implant specimens; Presence of microorganisms in deep tissue taken during an operative intervention, as confirmed by histopathological examination. Furthermore, a list of suggestive criteria was defined. These require further investigations in order to look for confirmatory criteria. In the current paper, an overview is provided of the proposed definition and a rationale for each component and decision. The intention of establishing this definition of FRI was to offer clinicians the opportunity to standardize clinical reports and improve the quality of published literature. It is important to note that the proposed definition was not designed to guide treatment of FRI and should be validated by prospective data collection in the future.

Single-stage treatment of chronic osteomyelitis with a new absorbable, gentamicin-loaded, calcium sulphate/hydroxyapatite biocomposite: a prospective series of 100 cases.

AIMS: Chronic osteomyelitis may recur if dead space management, after excision of infected bone, is inadequate. This study describes the results of a strategy for the management of deep bone infection and evaluates a new antibiotic-loaded biocomposite in the eradication of infection from bone defects. PATIENTS AND METHODS: We report a prospective study of 100 patients with chronic osteomyelitis, in 105 bones. Osteomyelitis followed injury or surgery in 81 patients. Nine had concomitant septic arthritis. 80 patients had comorbidities (Cierny-Mader (C-M) Class B hosts). Ten had infected nonunions. All patients were treated by a multidisciplinary team with a single-stage protocol including debridement, multiple sampling, culture-specific systemic antibiotics, stabilisation, dead space filling with the biocomposite and primary skin closure. RESULTS: Patients were followed up for a mean of 19.5 months (12 to 34). Infection was eradicated in 96 patients with a single procedure and all four recurrences were successfully managed with repeat surgery. Adverse events were uncommon, with three fractures, six wound leaks and three unrelated deaths. Outcome was not dependant on C-M host class, microbial culture, wound leakage or presence of nonunion. CONCLUSION: This single-stage protocol, facilitated by the absorbable local antibiotic, is effective in the treatment of chronic osteomyelitis. It offers a more patient-friendly treatment compared with other published treatment options. Cite this article: Bone Joint J 2016;98-B:1289-96.

Periosteal chondroma at birth.

Periosteal chondroma is a slow-growing, cartilaginous, surface tumor that usually occurs in the second and third decades of life. The youngest reported age at diagnosis is 5 years. Marginal excision is the treatment of choice. We report a case of a periosteal chondroma noted at birth and treated conservatively. This report expands the age range of periosteal chondroma to include neonates and suggests a role for observation in its management.

Differential effects of estrogen in the injured forebrain of young adult and reproductive senescent animals.

Estrogen attenuates neural damage resulting from a variety of experimental injury models in adult female rats. To determine whether estrogens neuroprotective actions are age-specific, the present study compared the effects of estrogen on young adult and reproductive senescent animals subject to excitotoxic injury to the forebrain. NMDA was injected bilaterally into the olfactory bulbs of estrogen and placebo-replaced young adult and reproductive senescent animals. Lysates of the olfactory bulb and its basal forebrain afferent, the horizontal limb of the diagonal band of Broca (hlDBB), harvested 24h later were analyzed for expression of IL-1beta, IL-10, and nerve growth factor (NGF). NMDA injections resulted in local activation of microglia and an increase in IL-1beta. Estrogen replacement decreased IL-1beta expression in young adult females, but paradoxically enhanced its expression in reproductive senescent females. Furthermore, bulb injury increased IL-1beta production in the hlDBB of reproductive senescent animals although estrogen replacement was able to suppress lesion-induced expression of this cytokine. In both, the olfactory bulb and hlDBB, constitutive expression of the anti-inflammatory cytokine IL-10 was significantly higher while that of NGF was almost 50% lower in senescent animals as compared to young adults, indicating that aging preferentially altered Th2-type secretions. The present findings are consistent with our earlier observations that estrogen does not exert trophic effects in the aging forebrain and supports the hypothesis that estrogen treatment to reproductive senescent females may exacerbate neural injury.

Clinical presentation, natural history, and cumulative death rates of 230 adults with primary cryptococcal meningitis in Zambian AIDS patients treated under local conditions.

SETTING: Inpatient medical wards, Department of Medicine, University Teaching Hospital, Lusaka, Zambia. OBJECTIVE: To define the natural history, clinical presentation, and management outcome of microbiologically confirmed cryptococcal meningitis in adult AIDS patients treated under local conditions where antifungal and antiretroviral therapies are not routinely available. DESIGN: A descriptive, longitudinal, observational study. METHODS: All adult patients admitted to the medical wards of the University Teaching Hospital, Lusaka, Zambia with cerebrospinal fluid culture proved, primary cryptococcal meningitis, during a 12 month period were enrolled into the study. The following details were acquired: clinical features, HIV status, laboratory data, treatment accorded, and survival. RESULTS: A total of 230 patients with primary cryptococcal meningitis were studied (median age 32 years; range 15-65 years; 112 males, 118 females). Cryptococcal meningitis was the first AIDS defining illness in 210 (91%) patients. One hundred and thirty of the 230 (56%) patients had received treatment with fluconazole monotherapy and 100 (43%) patients received palliative care only without any antifungal therapy. A 100% case fatality rate was observed in both groups at follow up: by seven weeks in the untreated group and at six months in the fluconazole treated group. The cumulative median survival from time of diagnosis was 19 days (range 1-164 days) for the fluconazole treated group and 10 days (range 0-42 days) for the untreated group. CONCLUSION: Cryptococcal meningitis, under current treatment accorded at the University Teaching Hospital, Lusaka, has a 100% mortality in young Zambian adults with AIDS. The current treatment accorded to Zambian adults with cryptococcal meningitis is inappropriate. An urgent need exists to improve strategies for the clinical management of AIDS patients in poor African countries. The wider ethical and operational issues of making available antifungals to African AIDS patients are discussed.

Pathologic fractures after surgery and radiation for soft tissue tumors.

Twenty pathologic fractures occurred in 285 patients with soft tissue tumors that were treated with radiation therapy and surgery. Twelve of these fractures occurred in 11 patients from a subpopulation of 163 patients with 168 soft tissue tumors of the thigh (155 soft tissue sarcomas and 13 aggressive fibromatosis). The fractures occurred at a mean of 40.5 months after treatment and were not associated with significant trauma. Risk factors associated with the development of fracture included tumor location within the anterior compartment of the thigh, extensive surgical periosteal stripping, and a marginal or intralesional margin of resection. The dose, timing, and fractionation of radiation therapy were not related to the risk of fracture. A high rate of complications was seen with this series, including fracture nonunion (45%) and deep infection (20%). Prophylactic intramedullary fixation of the femur should be considered for patients undergoing resection of large tumors in the anterior compartment of the thigh requiring extensive periosteal stripping and adjuvant radiation therapy.

Limb salvage surgery with vascular reconstruction.

Vascular reconstruction and limb salvage surgery has been the authors' preferred approach when malignancy involves major vessels of the extremities. Treatment of 16 patients involved resection, with vascular grafting in 14 patients and rotationplasty in two patients. The major vessels were surrounded by tumor in six patients, nearly encased in three patients, invaded by tumor in four patients, and widely contaminated by intralesional surgery in three patients. The tumor stage included one Stage IB, 12 Stage IIB, two Stage IIIB sarcomas, and one multiply recurrent carcinoma. The largest average tumor dimension was 9.5 cm, and the length of grafting was 14 cm. Major nerves were sacrificed in eight (50%) patients, flaps or muscle transfers were done in seven (44%), chemotherapy was administered in nine (56%), radiation therapy was used in four (25%), and pulmonary metastasectomy was done in two (12%). At a mean followup of 56 months, 50% (eight of 16) of patients were alive without disease. Local recurrence was 12% (two of 16 patients), and infection was 12% (two of 16 patients). Limb salvage was achieved in 88% (14 of 16 patients), and functional status was judged good or excellent in 81% (13 of 16 patients). The complication rate observed in this subset of patients is significant, yet local control and the incidence of major complications was acceptable. Results observed from this series and data gathered from the literature clearly indicate that patients can avoid amputation, despite malignant involvement of major vessels to their extremities.

NGF stimulation increases JNK2 phosphorylation and reduces caspase-3 activity in the olfactory bulb of estrogen-replaced animals.

Estrogen receptors are extensively colocalized with neurotrophins and their receptors in the rodent forebrain. We have shown previously that estrogen increases mRNA and protein expression of the nerve growth factor (NGF)-specific tyrosine kinase receptor, trkA, while decreasing expression of the universal neurotrophin receptor p75. In view of the pro-survival roles described for trks and the context-dependent stimulation of survival and cell death pathways activated by p75, differential regulation of these receptors by estrogen is likely to alter neurotrophin-dependent cell signaling. This hypothesis was tested in vivo, using the rodent olfactory bulb as a model. We found that NGF activated the extracellular signal-regulated protein kinase (ERK) equally in estrogen replaced and hormone-deprived animals. However in the case of c-jun-kinase (JNK), a related MAP kinase, pretreatment with estrogen altered NGF activation of a specific isoform of this protein. Specifically, NGF stimulation did not alter JNK1 or JNK2 activation in the estrogen-deprived condition, but significantly increased JNK2 activation in estrogen-replaced animals. Increased JNK2 phosphorylation in the NGF-injected, estrogen- replaced animals was paralleled by decreased activity of caspase-3, an enzyme required for apoptosis. In view of the disparate roles assigned to JNK, this latter finding suggests that estrogen pretreatment may preferentially direct neurotrophin-dependent JNK activation toward regeneration and plasticity rather than cell death.

The role of radiotherapy and limb-conserving surgery in the management of soft-tissue sarcomas in adults.

The treatment of soft-tissue sarcomas has undergone significant changes over the past several decades. Previously, patients were often treated with surgery alone, which frequently necessitated amputation of the affected extremity. Less extensive, limb-sparing operations combined with adjuvant irradiation are now feasible for most patients without compromising the likelihood of cure.

Megavoltage radiotherapy for aneurysmal bone cysts.

PURPOSE: An aneurysmal bone cyst (ABC) is a rapidly expansile and destructive benign tumor of bone that is usually treated by curettage and bone graft, with or without adjuvant treatment. For recurrent tumors, or tumors for which surgery would result in significant functional morbidity, does radiotherapy (RT) provide a safe and effective alternative for local control? PATIENTS AND METHODS: Nine patients with histologically diagnosed aneurysmal bone cysts without other associated benign or malignant tumors were treated at the University of Florida with megavoltage RT between February 1964 and June 1992. The patients received local radiotherapy doses between 20 and 60 Gy, with 6 patients receiving 26--30 Gy. In 6 patients the diagnosis was made by biopsy alone; 3 underwent intralesional curettage before RT. Minimum follow-up was 20 months; 7 of 9 patients (77%) had follow-up greater than 11 years. RESULTS: No patient experienced a local recurrence (median follow-up, 17 years). One patient required stabilization of the cervical spine 10 months after RT because of dorsal kyphosis from vertebral body collapse. No other significant side effects were experienced, and no patients developed secondary malignancies. Four patients were lost to follow-up: at 20 months, 11.5 years, 17 years, and 20 years after the initiation of treatment, none with any evidence of local recurrence. All of the patients who had significant pain before RT had relief of their symptoms within 2 weeks of completion of therapy. CONCLUSIONS: Using modern-day RT, patients with recurrent or inoperable aneurysmal bone cysts can be treated effectively (with minimal toxicity) using a prescribed tumor dose of 26--30 Gy.

Extra copies of chromosomes 7, 8, 12, 19, and 21 are recurrent in adamantinoma.

Adamantinoma of long bones is a rare neoplasm predominantly involving the tibia. Cytogenetic studies of adamantinoma are few. Cytogenetic or molecular cytogenetic analysis of four adamantinomas, and a review of eleven cases in the literature reveals extra copies of chromosomes 7, 8, 12, 19, and 21 as recurrent in this neoplasm. Adamantinoma may be confused with a variety of primary and metastatic epithelial and mesenchymal neoplasms. Observation of these aneuploidies may be useful in establishing the diagnosis of adamantinoma.

Allograft-allograft healing? Salvage of massive allografts after fracture.

Two cases are presented in which an allograft was inserted to salvage a previous allograft bone reconstruction that had followed resection for osteosarcoma. In each instance an allograft-allograft junction was created and, with time, healed. In the first case, a fracture of a distal femoral osteoarticular allograft was salvaged by adding a second allograft and a total knee arthroplasty. This construct preserved the majority of the allograft and allowed rapid rehabilitation. In the second case, an allograft arthrodesis of the knee was salvaged after fracture by replacing the distal portion of the fractured allograft with a new allograft. Again, an allograft-allograft junction was created and healed within 6 months. Allograft fractures pose challenging reconstructive problems. In these two cases, the addition of more allograft facilitated continued limb salvage and function.

The mechanism of metastasis.

The establishment of clinically detectable skeletal metastasis is a multifactorial process. This process can be divided into three general areas of understanding. The first is that of the intrinsic characteristics and properties of the tumor cells, which allow and facilitate their migration from the site of primary neoplasia to the distant host skeleton. Second, there are anatomic considerations of the human body, which influence the distribution of metastatic seeding. Third, there are the considerations of the host organism's biology, including the immune system, the circulatory system, and the affected host skeleton, which hinder and, at times, potentiate the ability of neoplastic cells to establish skeletal lesions.

Percutaneous radiofrequency ablation of osteoid osteoma.

Osteoid osteoma is a benign bone tumor. Patients usually require surgical treatment for reliable pain relief. Difficulties with intraoperative localization of the tumor and anatomic locations that carry a high morbidity with en bloc resection complicate open surgery. Various methods have been developed to lessen the invasiveness of surgery including computed tomography-guided percutaneous radiofrequency thermal ablation. Eleven patients in three different centers were evaluated and diagnosed with osteoid osteoma based on typical histories, physical examinations, and imaging studies. All patients were treated with computed tomography-guided percutaneous radiofrequency thermal ablation after medical treatment failed. Excellent pain relief was reported in 10 patients. One patient suffered recurrence of a femoral neck lesion despite an initial 7-month period without pain. Patients were given a questionnaire to quantify the effectiveness of percutaneous radiofrequency ablation in terms of pain relief and return to function. The current study shows that percutaneous radiofrequency thermal ablation provides reliable, excellent pain relief and early return to function with minimal morbidity as compared with traditional open techniques. The authors suggest that this technique be used for all patients with extraspinal osteoid osteomas that are not immediately adjacent to neurovascular structures.