[Persistent shoulder symptoms in calcific tendinitis: clinical and radiological predictors]. / Aanhoudende schouderklachten bij tendinitis calcarea.

OBJECTIVE: We assessed the most important demographics and radiological characteristics at the time of diagnosis of rotator cuff calcific tendinitis (RCCT), and their associations with long-term clinical outcome. DESIGN: Observational study. METHOD: Baseline characteristics and treatment were evaluated in 342 patients in whom RCCT had been diagnosed. Interobserver agreement of the radiological investigations was analysed. Patients were sent a general questionnaire and 2 shoulder questionnaires, the "Western Ontario rotator cuff" (WORC) and the "Disabilities of the arm, shoulder and hand" (DASH) for evaluation of long-term clinical outcome. Associations between baseline characteristics and long-term outcomes were analysed using logistic regression. RESULTS: Mean age at diagnosis was 49.0 years (SD = 10.0), and 60% were female. The dominant arm was affected in 66%, and 21% had bilateral RCCT. Calcifications were on average 18.7 mm in size (SD = 10.1, ICC = 0.84 (p < 0.001)) and located 10.1 mm (SD = 11.8) medially to the acromion (ICC = 0.77 (p < 0.001)). 32% of the calcifications had a Gärtner type I classification (κ: 0.47 (p<0.001)). After a mean follow-up of 14 years (SD =7.1), median WORC score was 72.5 (range: 3.0-100.0) and median DASH score 17.0 (range: 0.0-82.0). Female gender, dominant arm involvement, bilateral disease, longer duration of symptoms at presentation, and presence of multiple calcifications were associated with inferior long-term outcomes. CONCLUSION: RCCT is not self-limiting. Radiological variations have no significant predictive value. We identified specific prognostic factors for inferior long-term outcome; more intensive follow-up and treatment should be considered in patients with these characteristics.

Tibial anatomy in normal small breed dogs including anisometry of various extracapsular stabilizing suture attachment sites.

OBJECTIVES: To investigate proximal tibial anatomy and its influence on anisometry of extracapsular stabilizing sutures in small dog breeds. MATERIALS AND METHODS: Mediolateral radiographs of the femora, stifles, and tibiae of 12 small breed dogs were acquired with the stifles positioned at various angles. Measurements taken included tibial plateau angle (TPA), diaphyseal: proximal tibial angle (DPA), patellar tendon angle (PTA), Z-angle, relative tibial tuberosity width (rTTW), and the distance between six combinations of two femoral and three tibial extra-capsular stabilizing suture (ECS) attachment sites. Theoretical strain through stifle range-of-motion was recorded. RESULTS: The TPA (32° ± 5.8°), DPA (10.2° ± 7.3°), PTA (103.7° ± 6.2°), and Z-angle (70.4° ± 9.0°) were positively correlated with one another (R >0.7), but none were correlated with rTTW (0.93 ± 0.10). The F2-T1 combination of ECS attachment sites had lowest strain for nine stifles. The shortest attachment site separation was at a stifle flexion of 50° for nine stifles. Proximal tibial anatomy measurements could not predict optimal attachment site combination, optimal stifle angle for suture placement, or ECS strain. CLINICAL SIGNIFICANCE: There is individual variation in the optimal attachment site combination and stifle angle for suture placement, which may influence consistency of outcomes with ECS.

Chemical imaging of single catalyst particles with scanning µ-XANES-CT and µ-XRF-CT.

The physicochemical state of a catalyst is a key factor in determining both activity and selectivity; however these materials are often not structurally or compositionally homogeneous. Here we report on the 3-dimensional imaging of an industrial catalyst, Mo-promoted colloidal Pt supported on carbon. The distribution of both the active Pt species and Mo promoter have been mapped over a single particle of catalyst using microfocus X-ray fluorescence computed tomography. X-ray absorption near edge spectroscopy (XANES) and extended X-ray absorption fine structure revealed a mixed local coordination environment, including the presence of both metallic Pt clusters and Pt chloride species, but also no direct interaction between the catalyst and Mo promoter. We also report on the benefits of scanning µ-XANES computed tomography for chemical imaging, allowing for 2- and 3-dimensional mapping of the local electronic and geometric environment, in this instance for both the Pt catalyst and Mo promoter throughout the catalyst particle.

Management of feline distal tibial fractures using a hybrid external skeletal fixator.

OBJECTIVE: To document the results of management of feline distal tibial fractures with circular-linear hybrid external skeletal fixators. METHODS: Retrospective examination of case records and radiographs of cats with distal tibial fractures managed with hybrid external skeletal fixators. Signalment, pre-operative fracture conformation, post-operative fracture reduction, implant complications, time to tibial and fibular fracture healing and time to hybrid external skeletal fixators removal were analysed. RESULTS: Case records of eight cats were reviewed and included three closed fractures and five type 1 open fractures. Post-operative fracture reduction was considered appropriate in all cases. Healing of five tibial fractures was complete and hybrid external skeletal fixators were removed within a mean of 13 weeks. Healing of the fibular fracture was complete within a mean of 12 · 1 weeks. Three tibial fractures demonstrated non-union and were revised after a mean duration of 24 weeks. All three non-union fractures were open on presentation. CLINICAL SIGNIFICANCE: Feline distal tibial fractures may be managed with hybrid external skeletal fixators, however, non-union still occurs. In this study type I open feline distal tibial fractures appeared more likely to develop non-union.

Cranial translation of the humeral head on radiographs in rotator cuff tear patients: the modified active abduction view.

Cranial translation of the humeral head is related to massive rotator cuff tears; however, it may be unapparent in early-stage tears. The goal of this study was to investigate whether active abduction leads to increased active cranial humeral translation in early-stage tears. We assessed 20 consecutive patients (9 full-thickness supraspinatus tears, 11 posterosuperior tears) using the newly introduced modified active abduction view: acromiohumeral (AH) distance was measured on radiographs acquired during rest and active isometric abduction and adduction tasks with the arm alongside the body. Rest AH was 7.5 mm (SD = 1.53); during abduction and adduction, it decreased to 2.1 mm (95 % CI 1.28-3.01, p < 0.001) and 1.1 mm (95 % CI 0.46-1.65, p = 0.001), respectively. Cranial translation during abduction was more severe in shoulders with posterosuperior cuff tears (∆AH = 3 mm, SD = 1.5) compared to supraspinatus tears (∆AH = 1 mm, SD = 1.6), with a mean difference of 2 mm (95 % CI 0.64-3.58, p = 0.007). Both active isometric abduction and adduction leads to active cranial translation in cuff tear patients. Cranial translation is largest during active abduction. Furthermore, there is significant more cranial translation in posterosuperior cuff tear patients compared to supraspinatus cuff tear patients. Possibly, radiographs combined with active tasks offer new possibilities in diagnosing early-stage rotator cuff tears.

Cranial humerus translation, deltoid activation, adductor co-activation and rotator cuff disease - different patterns in rotator cuff tears, subacromial impingement and controls.

BACKGROUND: Arm adductor co-activation during abduction has been reported as a potential compensation mechanism for a narrow subacromial space in patients with rotator cuff dysfunction. We assessed differences in acromiohumeral distance at rest and the amount of humerus translation during active abduction and adduction in patients with rotator cuff tears (n=20) and impingement (n=30) and controls (n=10), controlled for deltoid, pectoralis major, latissimus dorsi and teres major activation (electromyography). METHODS: During the acquirement of shoulder radiographs, subjects performed standardized isometric arm abduction and adduction tasks. EMG's were normalized between -1 and 1 using the "Activation Ratio", where low values express (pathologic) co-activation, e.g. adductor activation during abduction. FINDINGS: In patients with cuff tears mean rest acromiohumeral distance was 7.6mm (SD=1.6): 3.5mm narrower compared to patients with impingement (95%-CI: 2.4-4.5) and 1.3mm narrower compared to controls (95%-CI: -0.1-2.7). Both during abduction and adduction tasks, cranial translation was observed with equal magnitudes for patients and controls, with average values of 2.3 and 1.7mm, respectively. Where patients with cuff tears had lower adductor Activation Ratios (i.e. more adductor co-activation during abduction), no association between abductor/adductor muscle activation and acromiohumeral distance was found. INTERPRETATION: The subacromial space is narrower in patients with rotator cuff tears compared to patients with impingement and controls. We found additional subacromial narrowing during isometric abduction and, to a lesser amount, during adduction in all subjects and more adductor co-activation in patients with cuff tears. We found no association between subacromial space and activation of the deltoid and main adductors.

Pathologic deltoid activation in rotator cuff tear patients: normalization after cuff repair?

Rotator cuff (RC) tears have a high prevalence, and RC repair surgery is frequently performed. Evaluation of deltoid activation has been reported as an easy to measure proxy for RC functionality. Our goal was to test the success of RC repair in restoring muscle function, by assessing deltoid activation with varying arm abduction moment loading tasks in controls and in RC tear patients before and 1 year after RC repair. Averaged rectified electromyography recordings (rEMG) of the deltoid during 2-s isometric arm abduction tasks were assessed in 22 controls and 33 patients before and after RC repair. Changes in deltoid activation as a response to increased arm abduction moment loading (large vs. small moment), without changing task force magnitude, were expressed as: R = (rEMGLarge - rEMGSmall)/(rEMGLarge + rEMGSmall), where R > 0 indicates an increase in muscle activation with larger moment loading. In controls, a significant increase in deltoid activation was observed with large abduction moment loading: R = 0.11 (95 % CI 0.06-0.16). In patients, R was larger: 0.20 (95 % CI 0.13-0.27) preoperatively and 0.16 (95 % CI 0.09-0.22) postoperatively. Increased compensatory deltoid activation was found in pre-operative RC tear patients. The post-operative decrease in compensatory deltoid activation, although not significant, could indicate (partially) restored RC function in at least some patients.

The Supraspinatus and the Deltoid - not just two arm elevators.

BACKGROUND: The debate on the clinical and functional role of the Supraspinatus in relation to the Deltoid necessitates experimental assessment of their contributions to arm elevation. Our goal was to evaluate the responses of both muscles to increased elevation moment loading. METHODS: Twenty-three healthy volunteers applied 30N elevation forces at the proximal and distal humerus, resulting in small and large glenohumeral elevation moment tasks. The responses of the Deltoid and Supraspinatus were recorded with surface and fine-wire electromyography, quantified by (EMGdistal-EMGproximal), and normalized by the summed activations (EMGdistal+EMGproximal) to RMuscle ratios. RESULTS: Deltoid activity increased with large elevation moment loading (RDE=.11, 95%-CI [.06-.16]). Surprisingly, there was no significant average increase in Supraspinatus activation (RSSp=.06, 95%-CI [-.08 to .20]) and its response was significantly more variable (Levene's test, F=11.7, p<.001). There was an inverse association between the responses (ß=-1.02, 95%-CI [-2.37 to .32]), indicating a potential complementary function of the Supraspinatus to the Deltoid. CONCLUSION: The Deltoid contributes to the glenohumeral elevation moment, but the contribution of the Supraspinatus is variable. We speculate there is inter-individual or intra-muscular function variability for the Supraspinatus, which may be related to the frequently reported variations in symptoms and treatment outcome of Supraspinatus pathologies.

Arm adductor with arm abduction in rotator cuff tear patients vs. healthy -- design of a new measuring instrument [corrected].

The incidence of (a)symptomatic rotator cuff tears is high, but etiologic mechanisms are unclear and treatment outcomes vary. A practical tool providing objective outcome measures and insight into etiology and potential patient subgroups is desirable. Symptomatic cuff tears coincide with humerus cranialization. Adductor co-activation during active arm abduction has been reported to reduce subacromial narrowing and pain in cuff patients. We present an easy-to-use method to evaluate adductor co-activation. Twenty healthy controls and twenty full-thickness cuff tear patients exerted EMG-recorded isometric arm abduction and adduction tasks. Ab- and adductor EMG's were expressed using the "Activation Ratio (AR)" (-1 ≤ AR ≤ 1), where lower values express more co-activation. Mean control AR's ranged from .7 to .9 with moderate to good test-retest reliability (ICC: .60-.74). Patients showed significantly more adductor co-activation during abduction, with adductor AR's ranging between .3 (teres major) and .5 (latissimus dorsi). In conclusion, the introduced method discriminates symptomatic cuff tear patients from healthy controls, quantifies adductor co-activation in an interpretable measure, and provides the opportunity to study correlations between muscle activation and humerus cranialization in a straightforward manner. It has potential as an objective outcome measure, for distinguishing symptomatic from asymptomatic cuff tears and as a tool for surgical or therapeutic decision-making.

Mid-term results of total hip arthroplasty with the CementLess Spotorno (CLS) system.

BACKGROUND: Except for those reported by the designers, there are no published mid-term results of the use of the CementLess Spotorno (CLS) Total Hip Arthroplasty system. We present the results of (1) a ten to seventeen-year follow-up prospective cohort study of this system, and (2) retrospective analyses of factors influencing clinical and radiographic outcomes. METHODS: We studied a series of 102 consecutive CLS arthroplasties with a minimal duration of follow-up of ten years. Indications for the procedures were osteoarthritis (n = 90), rheumatoid arthritis (n = 8), and femoral head osteonecrosis (n = 4). The Merle d'Aubigné-Postel score, polyethylene wear, and radiographic status were recorded at regular intervals. Survival analyses, repeated-measures analysis of variance, and a nested case-control study (with the cases having early revision due to aseptic cup loosening within ten years after the index procedure and the controls having no early cup revision) were used for evaluation. RESULTS: There were fourteen revisions, including nine due to aseptic cup loosening. The ten-year Kaplan-Meier survival rate was 92.2% (95% confidence interval [CI] = 86.9 to 97.5) with revision for any reason as the end point. The fifteen-year survival rate was 78.4% (95% CI = 63.9 to 92.9) with revision for any reason as the end point, 81.6% (95% CI = 66.7 to 96.5) with revision due to aseptic cup loosening as the end point, and 99.0% (95% CI = 97.0 to 100.0) with revision due to aseptic stem loosening as the end point. The average amount of polyethylene wear at the time of final follow-up was 1.92 mm (range, 0.6 to 4.3 mm). The wear rate in the cases was significantly higher than that in the controls (0.31 vs. 0.16 mm/yr, p < 0.001). Factors with a significant effect on polyethylene wear were age at surgery (a 0.3-mm increase per every ten years younger, p = 0.001) and a larger head component (an effect of 0.53 mm for the 32 vs. the 28-mm component; p < 0.0001). Male sex had an effect of -0.66 point (p = 0.07) on the final Merle d'Aubigné-Postel score. CONCLUSIONS: The results of this CLS system, particularly with regard to the femoral stem, are comparable with those with other reliable cementless systems. Nevertheless, the prevalence of aseptic acetabular cup loosening in the second decade after the operation demonstrates a potentially substantial problem with regard to long-term survival. A high polyethylene wear rate, male sex, a younger age at the time of surgery, and a 32-mm head component size are related to inferior clinical outcomes and a higher risk of implant revision.

Critical appraisal of the revised Ghent criteria for diagnosis of Marfan syndrome.

Marfan syndrome (MFS) is a connective tissue disorder with major features in cardiovascular, ocular and skeletal systems. Recently, diagnostic criteria were revised where more weight was given to the aortic root dilatation. We applied the revised Marfan nosology in an established adult Marfan population to define practical repercussions of novel criteria for clinical practice and individual patients. Out of 180 MFS patients, in 91% (n = 164) the diagnosis of MFS remained. Out of 16 patients with rejected diagnosis, four patients were diagnosed as MASS (myopia, mitral valve prolapse, borderline non-progressive aortic root dilatation, skeletal findings and striae) phenotype, three as ectopia lentis syndrome and in nine patients no alternative diagnosis was established. In 13 patients, the diagnosis was rejected because the Z-score of the aortic root was <2, although the aortic diameter was larger than 40 mm in six of them. In three other patients, the diagnosis of MFS was rejected because dural ectasia was given less weight in the revised nosology. Following the revised Marfan nosology, the diagnosis of MFS was rejected in 9% of patients, mostly because of the absence of aortic root dilatation defined as Z-score ≥2. Currently used Z-scores seem to underestimate aortic root dilatation, especially in patients with large body surface area (BSA). We recommend re-evaluation of criteria for aortic root involvement in adult patients with a suspected diagnosis of MFS.

Photodynamic therapy using topically applied hypericin: comparative effect with methyl-aminolevulinic acid on UV induced skin tumours.

Photodynamic therapy (PDT) is a treatment option particularly well-suited for superficial (pre)malignant skin lesions due to the skin's accessibility to light. In the present study, the efficacy of topical hypericin-PDT was evaluated using a mouse model for actinic keratosis. For comparison, similar experiments were conducted with methyl-aminolevulinic acid (Me-ALA). Small skin tumours (1-2 mm) were induced in hairless mice by chronic UV irradiation. After topical application of hypericin (0.1% in gelcream for 24 h) or Me-ALA (Metvix® for 4 h), the lesional/non-lesional skin surface fluorescence ratio was determined and fluorescence microscopy was used to study the skin penetration of the photosensitizers. The antitumour activity of topical PDT (20 mW cm(-2), 40 J cm(-2)) was evaluated by measurement of the lesional diameters. Moreover, biopsies were taken at various time points after PDT for histological evaluation of the therapy. Our results demonstrate that after topical application of hypericin and Me-ALA, tumour selectivity is limited in mouse skin. The microscopic distribution of hypericin fluorescence showed an accumulation in the stratum corneum and low fluorescence levels in the rest of the lesions, whereas the distribution of PpIX in the skin was more homogenous. Topical hypericin-PDT was found to be less efficient (44% total lesional clearance) as compared to Me-ALA-PDT (80% total lesional clearance). Full lesional necrosis was observed in responsive lesions, and the atypical cells of actinic keratosis were replaced by normal keratinocytes 3 weeks later, both after hypericin-PDT and Me-ALA-PDT.

Propagation of a partial incomplete ossification of the humeral condyle in an American cocker spaniel.

A hypoattenuating lesion in the left humeral condyle of an American cocker spaniel consistent with partial incomplete ossification of the humeral condyle was observed on computed tomography. Left forelimb lameness developed over the following three weeks at which time repeat computed tomography examination confirmed propagation of the lesion. Lameness resolved following placement of a transcondylar positional screw, suggesting that lameness was secondary to condylar instability. To the authors' knowledge this is the first report of propagation of an intracondylar lesion in a dog.

In vitro and in vivo multidrug resistance reversal activity by a Betti-base derivative of tylosin.

BACKGROUND: The multidrug resistance (MDR) proteins are present in a majority of human tumours. Their activity is important to understand the chemotherapeutic failure. A search for MDR-reversing compounds was conducted among various Betti-base derivatives of tylosin. METHODS: Here, we evaluate the in vitro and in vivo P-glycoprotein (P-gp)-modulating activity of the most promising compound N-tylosil-1-alpha-amino-(3-bromophenyl)-methyl-2-naphthol (TBN) using human MDR1 gene-transfected and parental L5178 mouse lymphoma cell lines. RESULTS: In vitro experiments showed that TBN dramatically increased the P-gp-mediated cellular uptake of the fluorescent substrate rhodamine 123. Similarly, TBN was found to act as a very potent enhancer of the cytotoxicity of doxorubicin on the resistant cell line. We also provide in vivo evidence using DBA/2 mice in support for an increased tumoural accumulation of doxorubicin, without affecting its tissue distribution, resulting in an enhanced antitumoural effect. CONCLUSION: Our results suggest that TBN is a potent modulator of the P-gp membrane pump and that the compound could be of clinical relevance to improve the efficacy of chemotherapy in MDR cancers.

Preliminary results of five feline total hip replacements.

Five feline total hip replacements (including one case of staged bilateral total hip replacement) for management of proximal femoral physeal fractures are reported. The surgical procedure was a modified version of that widely used in dogs. Craniodorsal luxation was the only major complication encountered. Subjectively outcomes appeared to be good in all cases.

Delayed spinal cord injury following microchip placement in a dog.

A three-year-old female, entire Yorkshire Terrier dog was examined because it had progressive non-weight-bearing left forelimb lameness and tetraparesis of two weeks duration. Clinical signs were first observed following mating. Examination confirmed non-weight-bearing left forelimb lameness and tetraparesis. Left forelimb muscle atrophy was also noticed. Survey radiography revealed a metallic foreign body consistent with a microchip in close proximity to the left articular facets between the fifth and sixth cervical vertebrae. Computed tomography identified the exact location of the foreign body encroaching on the left dorsolateral vertebral canal, and osteolysis of the lamina of the sixth cervical vertebra. Surgical removal of the foreign body was performed via a dorsal approach to the caudal cervical vertebral column. Two weeks following surgery the dog showed return of left forelimb function and resolving tetraparesis. Microchip implantation had been performed three years previously.

Bursectomy compared with acromioplasty in the management of subacromial impingement syndrome: a prospective randomised study.

In a prospective randomised study we compared the results of arthroscopic subacromial bursectomy alone with debridement of the subacromial bursa followed by acromioplasty. A total of 57 patients with a mean age of 47 years (31 to 60) suffering from primary subacromial impingement without a rupture of the rotator cuff who had failed previous conservative treatment were entered into the trial. The type of acromion was classified according to Bigliani. Patients were assessed at follow-up using the Constant score, the simple shoulder test and visual analogue scores for pain and functional impairment. One patient was lost to follow-up. At a mean follow-up of 2.5 years (1 to 5) both bursectomy and acromioplasty gave good clinical results. No statistically significant differences were found between the two treatments. The type of acromion and severity of symptoms had a greater influence on the clinical outcome than the type of treatment. As a result, we believe that primary subacromial impingement syndrome is largely an intrinsic degenerative condition rather than an extrinsic mechanical disorder.