Why are bone and soft tissue measurements of the TT-TG distance on MRI different in patients with patellar instability?

Purpose

To determine whether the tibial tuberosity-to-trochlear groove distance (TT-TG) and patellar tendon-to-trochlear groove distance (PT-TG) are equal, whether the bony and cartilaginous points coincide in the trochlea, and whether the insertion of the PT coincides with the most anterior point of the TT in patients with patellar instability.

Methods

Fifty-three MRI scans of patients with patellar instability were examined. TT-TG and PT-TG were measured by three examiners in 31 knees. Additionally, the bone–cartilage distance in the trochlea [trochlear cartilage to trochlear bone (TC-TB)] and the distance between the mid-point of the PT insertion and the most anterior point of the TT (PT-TT) were measured by one examiner. The intraclass correlation coefficient was used to evaluate the reliability of the measurements between the three examiners. The relationships between the measurements were determined, the means of the measurements were calculated, and the correlations between PT-TG and TT-TG, PT-TT, and TC-TB were assessed.

Results

The ICC was above 0.8. PT-TG was 3.7 mm greater than TT-TG. The TC and TB coincided in 73 % of cases, and the mean TC-TB was 0.3 mm. The PT was lateral to the TT in 94 % of the cases, and the mean PT-TT was 3.4 mm. The Pearson’s correlation coefficients between PT-TG and TT-TG, PT-TT, and TC-TB were 0.946, 0.679, and 0.199, respectively.

Conclusion

TT-TG underestimated PT-TG, primarily due to the lateralization of the PT insertion relative to the most anterior point of the TT. Clinical relevance: our study shows that in patients with patellar instability, there are differences in the absolute values of TT-TG and PT-TG, as previously reported for patients without patellar instability. Hence, normal cut-off values based on case–control studies of TT-TG cannot be equivalently used when measuring PT-TG to indicate TT medialization in patients with patellar instability. It is also important to note that the clinical outcomes cannot be directly compared between patients evaluated using TT-TG versus PT-TG measurements.

Level of evidence

III.

     

Collection of peripheral blood progenitor cells for autologous use: performance enhancements of COBE spectra, auto-PBSC

Collection of peripheral blood stem cells (PBSC) must be performed in a safe and effective manner. Issues like automation, collection efficiency (CE), and adverse events must be considered. Auto-PBSC (COBE Spectra) is a fully automated program for PBSC collection. Changes in the protocol were made to achieve high CE, low product volume, and resulted in three groups of patients. Standard operating procedures (SOPs) were developed to reduce citrate toxicity and patients with central venous catheter. Twenty patients and 27 collections (Group 1), 88 patients and 112 collections (Group 2), and 158 patients and 194 collections (Group 3) were recorded. The protocol changes increased CE significantly from 31% (Group 1) to 57 and 59% (Group 2 and 3). Adjusting endpoint according to the preapheresis number of CD34+ cells reduced the collection time and the volume of the product significantly (median 227 min and 56 mL) without affecting CE. Mean level of ionized calcium before collection was 1.22 mmol/L, measured in 31 patients. This declined to a mean of 1.07 mmol/L after 1 h of collection and remained unchanged despite continuous calcium infusion. The number of patients with mild symptoms of citrate toxicity was reduced from 20 to 6%. A central venous catheter was used in 15%. Compared to peripheral access no differences in blood flow rate or time to perform the collection were found. Changes in the Auto-PBSC protocol resulted in an improved CE and a small product. SOPs reduced the number of patients with citrate toxicity and with central venous catheter.     

Analysis of HER-3, insulin growth factor-1, nuclear factor-kB and epidermal growth factor receptor gene copy number in the prediction of clinical outcome for K-RAS wild-type colorectal cancer patients receiving irinotecan-cetuximab

BackgroundA large proportion of colorectal cancer patients does not benefit from the use of anti-epidermal growth factor receptor (EGFR) treatment although in the absence of a mutation of the K-RAS gene. Preliminary observations suggested that HER-3, insulin-like growth factor-1 (IGF-1), nuclear factor-kB (NF-kB) and EGFR gene copy number (GCN) might identify patients not likely to benefit from anti-EGFR therapy. We tested the interaction between HER-3, IGF-1, NF-kB, EGFR GCN and K-RAS mutational analysis to verify the relative ability of these variables to identify a subgroup of patients more likely to benefit from EGFR-targeted treatment among those harbouring a K-RAS wild-type status.Patients and methodsWe retrospectively collected tumours from 168 patients with metastatic colorectal cancer treated with irinotecan–cetuximab. K-RAS was assessed with direct sequencing, EGFR amplification was assessed by chromogenic in situ hybridisation (CISH) and HER-3, IGF-1 and NF-kB were assessed by immunohistochemistry.ResultsIn patients with K-RAS wild-type tumours, the following molecular factors resulted independently associated with response rate: HER-3 [odds ratio (OR) = 4.6, 95% confidence interval (CI) 1.8–13.6, P = 0.02], IGF-1 (OR = 4.2, 95% CI 2–10.2, P = 0.003) and EGFR GCN (OR = 4.1, 95% CI 1.9–26.2, P = 0.04). These factors also independently correlated with overall survival as follows: HER-3 [hazard ratio (HR) = 0.4, 95% CI 0.28–0.85, P = 0.008], IGF-1 (HR = 0.47, 95% CI 0.24–0.76, P < 0.0001) and EGFR GCN (HR = 0.59, 95% CI 0.22–0.89, P = 0.04).DiscussionWe believe that our data may help further composing the molecular mosaic of EGFR-resistant tumours. The role of HER-3, IGF-1 and CISH EGFR GCN should be prospectively validated in clinical trials investigating anti-EGFR treatment strategies in colorectal cancer patients.     

Comparative study of histopathological and immunohistochemical findings in skin biopsies from patients with psoriasis before and after treatment with acitretin

Background:  Acitretin has been shown to be effective for psoriasis treatment. Its mechanism of action is not completely understood, and there are few studies focusing on histological and immunohistochemical differences before and after treatment of psoriasis with acitretin.
Methods:  This is a prospective study of 17 patients with plaque psoriasis treated with acitretin for 4 months with biopsies taken before and after therapy. Histological features and immunohistochemical reactions to cytokeratin (CK) 10, CK16, CK19, Ki67 and CD1a were evaluated and compared.
Results:  There were nine men and eight women with median age of 47 years. Epidermal thickness, CK16 positivity, Ki67 and CD1a-positive cell index reduced after treatment (p < 0.01). Suprapapillary plate thickness stayed the same (p > 0.05) although the epidermal/suprapapillary thickness ratio was significantly higher before treatment (p < 0.01). CK10 positivity was lower and a thicker basal cell layer was seen in the epidermis before treatment (p < 0.01). CK19 was negative in all cases.
Conclusions:  Acitretin therapy improved histological and immunohistochemical features typical of psoriasis. In psoriasis, suprapapillary plates are not thin, but the epidermal/suprapapillary thickness ratio is increased. Basal cell layer is expanded in psoriasis. Langerhans' cells were less frequent after treatment, and that finding has to be investigated further to determine its role in acitretin mechanism of action.     

Patients with acute myocardial infarction and interfering factors when seeking emergency care: implications for health education

With the objective of estimating the time elapsed between the beginning of the signs and symptoms of a heart attack until the arrival at the cardiology emergency service (Delta T) and the factors that influence in this process, 112 patients were studied, with an infarction diagnosis with supraunleveling ST segment. The delta T was on average of 3h59+/-2h55min; 99(88%) of those patients sought out an emergency service within 1h after the beginning of the event. Unmarried patients presented a delta T smaller in relation to the others (P=0,006), as well as those that recognized the symptoms as a heart event; thoracic pain with burning symptoms, were described by 25 (24%) of patients, and the first attitude taken, in view those symptoms, was self-medication 37(33%). The recognition of the signs and symptoms of Acute Myocardium Infarction, is a decisive factor for the seeking of a specialized service.