Limb development in skeletally-immature large-sized dogs: A radiographic study

Despite the extreme morphological variability of the canine species, data on limb development are limited and the time windows for the appearance of the limb ossification centres (OCs) reported in veterinary textbooks, considered universally valid for all dogs, are based on dated studies. The aim of this study was to acquire up-to-date information regarding the arm, forearm and leg bone development in skeletally-immature large-sized dogs from 6 weeks to 16 weeks of age. Nine litters of 5 large-sized breeds (Boxer, German Shepherd, Labrador Retriever, Saarloos Wolfdog, White Swiss Shepherd Dog) were included, for a total of 54 dogs, which were subject to radiographic examination on a bi-weekly basis. The appearance of 18 limb OCs was recorded and 14 radiographic measurements were performed; their relationship with age and body weight was investigated and any breed differences were analysed using different statistical non-parametric tests. The number of OCs present was significantly different at 6 and 8 weeks of age between the investigated breeds. The appearance of the OCs occurred earlier in the Saarloos Wolfdog, while the Labrador Retriever was the later breed. In Boxers and Labrador Retrievers, various OCs showed a delayed appearance compared to the data reported in the literature. The number of OCs was strongly and positively correlated to body weight. Breed differences were also observed in the relative increase of the measured OCs and were not limited to dogs of different morphotypes. Statistically significant differences were most frequently observed between Saarloos Wolfdogs and the other breeds. The OCs that showed a greater variability in their development were the olecranon tuber, the patella and the tibial tuberosity. Their increase was more strongly correlated with the dog’s age and body weight. Our data strongly suggest that differences in limb development exist in dog breeds of similar size and morphotype.

Basic morphometry, microcomputed tomography and mechanical evaluation of the tibiotarsal bone of a dual-purpose and a broiler chicken line

Continuous loading of the skeleton by the body’s weight is an important factor in establishing and maintaining bone morphology, architecture and strength. However, in fast-growing chickens the appendicular skeleton growth is suboptimal making these chickens predisposed to skeletal mineralization disorders and fractures. This study compared the macro- and microstructure as well as the mechanical properties of the tibiotarsus of a novel dual-purpose, Lohmann Dual (LD) and a highly developed broiler, Ross (Ross 308) chicken line. Eighty one-day-old male chicks of each line were grown until their body weight (BW) reached 2000g. Starting at the day of hatching, six birds of each line were sampled weekly. The weight, length and width of the tibiotarsus were measured and its mechanical properties (rigidity, M-Max and the M-fracture) were evaluated using the three-point bending test. Additionally, the mineral density of both, trabecular and cortical bone, the bone volume fraction, the trabecular number, thickness and separation plus cortical thickness of both chicken lines were analyzed using microcomputed tomography. The growth of the tibiotarsus in both chicken lines followed a similar pattern. At the same age, the lighter LD chickens had shorter, thinner and lighter tibiotarsi than those of Ross chickens. However, the LD chickens had a similar cortical thickness, bone volume fraction and similar mineral density of both trabecular and cortical bone to that of Ross chickens. Furthermore, the tibiotarsus of LD chickens was longer, heavier and wider than those of Ross chickens of the same BW. In addition the rigidity of the LD tibiotarsus was greater than that of Ross chickens. This suggests that the tibiotarsus of LD chickens had more bending resistance than those of Ross chickens of the same BW. Consequently, fattening LD chickens to the marketable weight should not affect their leg skeleton stability.

Effects of adjuvant exemestane versus anastrozole on bone mineral density for women with early breast cancer (MA.27B): a companion analysis of a randomised controlled trial

BACKGROUND

Treatment of breast cancer with aromatase inhibitors is associated with damage to bones. NCIC CTG MA.27 was an open-label, phase 3, randomised controlled trial in which women with breast cancer were assigned to one of two adjuvant oral aromatase inhibitors-exemestane or anastrozole. We postulated that exemestane-a mildly androgenic steroid-might have a less detrimental effect on bone than non-steroidal anastrozole. In this companion study to MA.27, we compared changes in bone mineral density (BMD) in the lumbar spine and total hip between patients treated with exemestane and patients treated with anastrozole.

METHODS

In MA.27, postmenopausal women with early stage hormone (oestrogen) receptor-positive invasive breast cancer were randomly assigned to exemestane 25 mg versus anastrozole 1 mg, daily. MA.27B recruited two groups of women from MA.27: those with BMD T-scores of -2·0 or more (up to 2 SDs below sex-matched, young adult mean) and those with at least one T-score (hip or spine) less than -2·0. Both groups received vitamin D and calcium; those with baseline T-scores of less than -2·0 also received bisphosphonates. The primary endpoints were percent change of BMD at 2 years in lumbar spine and total hip for both groups. We analysed patients according to which aromatase inhibitor and T-score groups they were allocated to but BMD assessments ceased if patients deviated from protocol. This study is registered with ClinicalTrials.gov, NCT00354302.

FINDINGS

Between April 24, 2006, and May 30, 2008, 300 patients with baseline T-scores of -2·0 or more were accrued (147 allocated exemestane, 153 anastrozole); and 197 patients with baseline T-scores of less than -2·0 (101 exemestane, 96 anastrozole). For patients with T-scores greater than -2·0 at baseline, mean change of bone mineral density in the spine at 2 years did not differ significantly between patients taking exemestane and patients taking anastrozole (-0·92%, 95% CI -2·35 to 0·50 vs -2·39%, 95% CI -3·77 to -1·01; p=0·08). Respective mean loss in the hip was -1·93% (95% CI -2·93 to -0·93) versus -2·71% (95% CI -4·32 to -1·11; p=0·10). Likewise for those who started with T-scores of less than -2·0, mean change of spine bone mineral density at 2 years did not differ significantly between the exemestane and anastrozole treatment groups (2·11%, 95% CI -0·84 to 5·06 vs 3·72%, 95% CI 1·54 to 5·89; p=0·26), nor did hip bone mineral density (2·09%, 95% CI -1·45 to 5·63 vs 0·0%, 95% CI -3·67 to 3·66; p=0·28). Patients with baseline T-score of -2·0 or more taking exemestane had two fragility fractures and two other fractures, those taking anastrozole had three fragility fractures and five other fractures. For patients who had baseline T-scores of less than -2·0 taking exemestane, one had a fragility fracture and four had other fractures, whereas those taking anastrozole had five fragility fractures and one other fracture.

INTERPRETATION

Our results demonstrate that adjuvant treatment with aromatase inhibitors can be considered for breast cancer patients who have T-scores less than -2·0.

FUNDING

Canadian Cancer Society Research Institute, Pfizer, Canadian Institutes of Health Research.

Osteosarcoma of limb bones: a clinical, radiological and histopathological diagnostic agreement at Black Lion Teaching Hospital, Ethiopia

OBJECTIVES

To measure the strength of agreement in clinical, radiological and histopathological diagnosis of osteosarcoma in a 5 year study period.

SETTING

Addis Ababa University, Black-Lion ('Tikur Anbessa') Hospital-BLH, is the country's highest tertiary level referral and teaching hospital. The departments involved in this study (Radiology, Pathology and Orthopedics) receive referred patients from all over the country.

METHODS

All bone tumor patients, presenting to the three departments at BLH between the study period, December, 2003 - March, 2008 were recruited for the study. 51 patients with radiological diagnosis of osteosarcoma of the extremities were identified and their clinical and histopathological diagnoses reviewed in detail. All patients had a clinical examination, plain radiographs and biopsies of the affected part of the extremity. Radiographs of selected difficult cases were discussed at joint orthopedic & radiologic sessions every week. The radiological and histopathological diagnoses made were categorized separately using WHO classification of bone tumors. Strength of agreement between radiological and histopathological diagnoses was measured using Cohen's Kappa test.

RESULTS

Of the total of 216 bone tumor patients presented and biopsied in the five year period, fifty one (51) had osteosarcoma of extremity bones. Commonest age affected by osteosarcoma was 16 (7-55 years) and sex ratio was 1:1. Osteosarcoma was also the single most common clinical, radiological and histological diagnosis made. Considering all bone tumors presented together, the study indicated that radiological diagnosis was confirmed by similar histological diagnosis in 172 out 205 cases (84%) and the corresponding Cohen's Kappa value (0.82) showed excellent level of agreement between radiological and histological diagnoses of all bone tumors. The agreement between radiological and histopathological diagnoses of osteosarcoma of the limbs was 84.5%.

CONCLUSION

There is an excellent agreement between clinical, radiological and histopathological diagnoses of bone tumors in general and osteosarcoma in particular. In setups where there is limited or no histopathological service, joint clinical and radiological decision could lead to a higher degree of accuracy in diagnosis of bone tumors, especially osteosarcoma. Radiological diagnosis of bone tumors at Black Lion Hospital, Addis Ababa is excellent.

Severe bilateral rachitic genu valgum in patients with nonbullous congenital ichthyosiform erythroderma: a report of two cases and review of literature

We present two cases of ichthyosiform erythroderma associated with severe bilateral genu valgum. Other musculoskeletal features associated with this condition are described. The details and outcome of operative intervention for the correction of the deformities are discussed. The disturbances of the metabolism of vitamin D and medical management are discussed. A review of literature is presented.

Correction of deformities in children using the Taylor spatial frame

The Taylor spatial frame is a unique external fixator. Despite its growing popularity, few reports on its use have been published. We evaluated the effectiveness of the Taylor spatial frame in the treatment of various deformities in 31 children and adolescents. All but one patient were anatomically corrected. Complications included superficial pin tract infection (45%), three fractures of the femoral regenerate, transient peroneal palsy, and injury to the genicular artery. Despite many challenging problems, our results compared favorably with the results achieved by others. We believe that the Taylor spatial frame is a very capable and accurate fixator for the precise correction of complex deformities.

A complementary method for the detection of osteoblastic metastases on digitized radiographs

PURPOSE

This study was conducted to evaluate the diagnostic usefulness of gray level parameters in order to distinguish healthy bone from osteoblastic metastases on digitized radiographs.

MATERIALS AND METHODS

Skeletal radiographs of healthy bone (n = 144) and osteoblastic metastases (n = 35) were digitized using pixels 0.175 mm in size and 4,096 gray levels. We obtained an optimized healthy bone classification to compare with pathological bone: cortical, trabecular, and flat bone. The osteoblastic metastases (OM) were classified in nonflat and flat bone. These radiological images were analyzed by using a computerized method. The parameters (gray scale) calculated were: mean, standard deviation, and coefficient of variation (MGL, SDGL, and CVGL, respectively) based on gray level histogram analysis. Diagnostic utility was quantified by measurement of parameters on healthy and pathological bone, yielding quantification of area under the receiver operating characteristic (ROC) curve, AUC.

RESULTS

All three image parameters showed high and significant values of AUC when comparing healthy trabecular bone and nonflat bone OM, showing MGL the best discriminatory ability (0.97). As for flat bones, MGL showed no ability to distinguish between healthy and flat bone OM (0.50). This could be achieved by using SDGL or CVGL, with both showing a similar diagnostic ability (0.85 and 0.83, respectively).

CONCLUSION

Our results show that the use of gray level parameters quantify healthy bone and osteoblastic metastases zones on digitized radiographs. This may be helpful as a complementary method for differential diagnosis. Moreover, our method will allow us to study the evolution of osteoblastic metastases under medical treatment.

Increases in bone mineral density after functional electrical stimulation cycling exercises in spinal cord injured patients

PURPOSE

To assess the change in bone mineral density (BMD) after spinal cord injury (SCI) and to evaluate whether BMD loss can be reversed with the intervention of functional electric stimulation cycling exercises (FESCE).

METHODS

Fifteen males with SCI were included. Fifteen able-bodied males were also tested to compare BMD. In the SCI group, the FESCE was performed for six months, and then was discontinued in the subsequent six months. BMD was performed before the FESCE, immediately after six months of the FESCE, and at the end of the subsequent six months.

RESULTS

Before the FESCE, the BMD of the SCI subjects in every site, except the lumbar spine, was lower than that of the able-bodied subjects. After six months of FESCE, BMD of the distal femur (DF) and proximal tibia (PT) increased significantly, and BMD of the calcaneus (heel) showed a trend of increase. However, the BMD in the DF, PT, and heel decreased significantly after the subsequent six months without FESCE. The BMD of the femoral neck (FN) decreased progressively throughout the programme.

CONCLUSIONS

Our study showed site-specific BMD changes after FESCE. The BMD loss in the DF and PT was partially reversed after six months of FESCE, but the effect faded once the exercise was discontinued.