Fibre optic confocal imaging (FOCI) of keratinocytes, blood vessels and nerves in hairless mouse skin in vivo

Fibre optic confocal imaging (FOCI) enabled subsurface fluorescence microscopy of the skin of hairless mice in vivo. Application of acridine orange enabled imaging of the layers of the epidermis. The corneocytes of the stratum corneum, the keratinocytes in the basal layers and redundant hair follicles were visualised at depths greater than 100 μm. Cellular and nuclear membranes of keratinocytes of the skin were visualised by the use of acridine orange and DIOC5(3). Imaging of the skin after injection of FITC-dextran revealed an extensive network of blood vessels with a size range up to 20 μm. Blood cells could be seen moving through dermal vessels and the blood circulation through the dermal vascular bed was video-taped. The fluorescent dye 4-di-2-ASP showed the presence of nerves fibres around the hair follicles and subsurface blood vessels. Comparison was made between images obtained in vivo using FOCI and in vitro scanning electron microscopy and conventional histology. FOCI offers the potential to study dynamic events in vivo, such as blood flow, skin growth, nerve regeneration and many pathological processes, in ways which have not previously been possible.     

Acquired Idiopathic Stiffness After Contemporary Total Knee Arthroplasty: Incidence,Risk Factors,and Results Over 25 Years

BackgroundAcquired idiopathic stiffness (AIS) remains a common failure mode of contemporary total knee arthroplasties (TKAs). The present study investigated the incidence of AIS and manipulation under anesthesia (MUA) at a single institution over time, determined outcomes of MUAs, and identified risk factors associated with AIS and MUA.MethodsWe identified 9771 patients (12,735 knees) who underwent primary TKAs with cemented, modular metal-backed, posterior-stabilized implants from 2000 to 2016 using our institutional total joint registry. Mean age was 68 years, 57% were female, and mean body mass index was 33 kg/m². Demographic, surgical, and comorbidity data were investigated via univariate Cox proportional hazard models and fit to an adjusted multivariate model to access risk for AIS and MUA. Mean follow-up was 7 years.ResultsDuring the study period, 456 knees (3.6%) developed AIS and 336 knees (2.6%) underwent MUA. Range of motion (ROM) increased a mean of 34° after the MUA; however, ROM for patients treated with MUA was inferior to patients without AIS at final follow-up (102° vs 116°, P < .0001). Significant risk factors included younger age (HR 2.3, P < .001), increased tourniquet time (HR 1.01, P < .001), general anesthesia (HR 1.3, P = .007), and diabetes (HR 1.5, P = .001).ConclusionAcquired idiopathic stiffness has continued to have an important adverse impact on the outcomes of a subset of patients undergoing primary TKAs. When utilized, MUA improved mean ROM by 34°, but patients treated with MUA still had decreased ROM compared to patients without AIS. Importantly, we identified several significant risk factors associated with AIS and subsequent MUA.Level of EvidenceLevel III, retrospective comparative study.     

Primary myelofibrosis: risk stratification by IPSS identifies patients with poor clinical outcome

OBJECTIVES:

To evaluate whether risk scores used to classify patients with primary myelofibrosis and JAK-2 V617F mutation status can predict clinical outcome.

METHODS:

A review of clinical and laboratory data from 74 patients with primary myelofibrosis diagnosed between 1992 and 2011. The IPSS and Lille scores were calculated for risk stratification and correlated with overall survival.

RESULTS:

A V617F JAK2 mutation was detected in 32 cases (47%), with no significant correlation with overall survival. The patients were classified according to the scores: Lille - low, 53 (73.%); intermediate, 13 (18%); and high, 5 (7%); and IPSS – low, 15 (26%); intermediate-1, 23 (32%); intermediate-2, 19 (26%); and high, 15 (31%). Those patients presenting a higher risk according to the IPSS (high and intermediate-2) had a significantly shorter overall survival relative to the low risk groups (intermediate-1 and low) (p = 0.02).

CONCLUSIONS:

These results emphasize the importance of the IPSS prognostic score for risk assessment in predicting the clinical outcome of primary myelofibrosis patients.     

Radiologic case study. Abrasion chondroplasty mimicking avascular necrosis

Arthroscopic abrasion arthroplasty, subchondral drilling, and microfracture continue to be performed with some frequency in younger patients with focal chondral defects and occasionally for patients with moderate degenerative knee arthritis. The plain radiographic appearance after those procedures may mimic avascular necrosis, but MRI is a sensitive method used to exclude the diagnosis of avascular necrosis and evaluate the extent to which fibrocartilaginous repair tissue has formed. When combined with an appropriate clinical history, dedicated articular cartilage imaging sequences improve the sensitivity and specificity that MRI provides in these patients with chondral knee injuries.     

Successful nonoperative management of chronic osteoarthritis pain of the knee: safety and efficacy of retreatment with intra-articular hyaluronans

CONTEXT: Although there are many nonsurgical therapies available for the treatment of pain associated with osteoarthritis (OA), their long-term use and safety have not been systematically followed. Intra-articular hyaluronan therapy has been used in the treatment of symptoms associated with OA of the knee with a very favorable safety profile. Five intra-articular hyaluronan products are approved in the US. No systematic review of the safety and efficacy of their chronic use has been reported. OBJECTIVE: To evaluate the literature on the efficacy and safety of repeat courses of hyaluronan therapy in patients with OA of the knee. DATA SOURCES: MEDLINE, EMBASE, searched through October 2004. STUDY SELECTION: Databases were searched using the terms hyaluronan, sodium hyaluronate, hyaluronic acid, hylan, hylan G-F 20, osteoarthritis, adverse events, repeat treatment, and multiple courses. DATA SYNTHESIS: There are some data that support the benefit and safety of repeat treatment for all products. Data also indicate that one formulation of sodium hyaluronate (molecular weight [MW] 500-730 kDa) is well tolerated and as effective after multiple courses of treatment as it is after a single course. There is also clinical evidence that prolonged use of sodium hyaluronate (MW 500-730 kDa) may significantly decrease the rate of deterioration of joint structure. Localized severe acute inflammatory reactions reported with repeated treatment in some patients are not a class effect but may be linked to physicochemical characteristics of hylan-based treatment. CONCLUSIONS: Repeat courses of the hyaluronans are safe and effective in the treatment of pain associated with OA of the knee.     

Total knee arthroplasty for patients 90 years of age and older

This study was done to review the reliability, durability, and safety of primary and revision total knee arthroplasty for patients 90 years of age and older. Because little data exist about the safety or efficacy of total knee replacement in this elderly population some physicians may be hesitant to recommend elective surgery to patients of this age. Fifty-one total knee replacements were done for 41 patients age 90 to 102 years (mean, 92 years). Forty-four primary total knee replacements and seven revision total knee replacements were done. Each patient was followed up until death or for a minimum of 2 years (mean, 4.0 years). The Knee Society pain scores improved significantly for the primary and revision groups from preoperative mean scores of 30 and 29 points to latest followup scores of 86 and 87 points, respectively. One patient died in the early postoperative period of causes related to the operation. The remaining patients have lived an average of 4.4 +/- 2.2 years after the primary knee arthroplasties and 5.7 +/- 2.8 years after the revision knee arthroplasties. No knees have required revision subsequently. Total knee replacement was reliable, durable, and safe in this group of patients older than 90 years. Primary care physicians and surgeons should be aware that primary and revision total knee replacement can be done safely and effectively for patients 90 years and older and result in years of marked pain relief for those patients.