Gait propulsion in patients with facioscapulohumeral muscular dystrophy and ankle plantarflexor weakness.

Facioscapulohumeral muscular dystrophy is a slowly progressive hereditary disorder resulting in fatty infiltration of eventually most skeletal muscles. Weakness of trunk and leg muscles causes problems with postural balance and gait, and is associated with an increased fall risk. Although drop foot and related tripping are common problems in FSHD, gait impairments are poorly documented. The effect of ankle plantarflexor involvement on gait propulsion has never been addressed. In addition to ankle plantarflexion, gait propulsion is generated through hip flexion and hip extension. Compensatory shifts between these propulsion sources occur when specific muscles are affected. Such a shift may be expected in patients with FSHD since the calves may show early fatty infiltration, whereas iliopsoas and gluteus maximus muscles are often spared for a longer time. In the current study, magnetic resonance imaging was used to assess the percentage of unaffected calf, iliopsoas and gluteus maximus muscles. Joint powers were analyzed in 10 patients with FSHD at comfortable and maximum walking speed to determine the contribution of ankle plantarflexor, hip flexor and hip extensor power to propulsion. Associations between muscle morphology, power generation and gait speed were assessed. Based on multivariate regression analysis, ankle plantarflexor power was the only factor that uniquely contributed to the explained variance of comfortable (R(2)=80%) and maximum (R(2)=86%) walking speed. Although the iliopsoas muscles were largely unaffected, they appeared to be sub-maximally recruited. This submaximal recruitment may be related to poor trunk stability, resulting in a disproportionate effect of calf muscle affliction on gait speed in patients with FSHD.

Trunk muscle involvement is most critical for the loss of balance control in patients with facioscapulohumeral muscular dystrophy.

BACKGROUND: Although it is known that muscle weakness is a major cause of postural instability and leads to an increased incidence of falls in patients with neuromuscular disease, the relative contribution of lower extremity and trunk muscle weakness to postural instability has not been studied well. METHODS: We determined the relationship between muscle fatty infiltration and sagittal-plane balance in ten patients with facioscapulohumeral muscular dystrophy. Sagittal-plane platform translations were imposed in forward and backward directions on patients with facioscapulohumeral muscular dystrophy and healthy controls. Stepping thresholds were determined and kinematic responses and center-of-mass displacements were assessed using 3 dimensional motion analysis. In the patients, magnetic resonance imaging was used to determine the amount of fatty infiltration of trunk and lower extremity muscles. FINDINGS: Stepping thresholds in both directions were decreased in patients compared to controls. In patients, significant correlations were found for fatty infiltration of ventral muscles with backward stepping threshold and for fatty infiltration of dorsal muscles with forward stepping threshold. Fatty infiltration of the rectus abdominis and the back extensors explained the largest part of the variance in backward and forward stepping thresholds, respectively. Center-of-mass displacements were dependent on intensity and direction of perturbation. Kinematic analysis revealed predominant ankle strategies, except in patients with lumbar hyperlordosis. INTERPRETATION: These findings indicate that trunk muscle involvement is most critical for loss of sagittal-plane postural balance in patients with facioscapulohumeral muscular dystrophy. This insight may help to develop rehabilitation strategies to prevent these patients from falling.

Bone cysts in patients with afibrinogenaemia: a literature review and two new cases.

Afibrinogenaemia is an autosomal recessive disease with an estimated prevalence of approximately one in a million. The most common symptoms of afibrinogenaemia are umbilical cord bleeding, bleeding into skin, mouth, muscles, gastrointestinal and genitourinary tracts and the central nervous system. Other recognized complications include; haemarthroses, spontaneous splenic rupture, epistaxis, menorrhagia, recurrent abortion and venous and arterial thromboembolism. Bone cysts have also been described as a rare complication of afibrinogenaemia. The aim of this study was to conduct a systematic literature review, summarize the reported cases and to report two new cases. Three electronic databases were searched for relevant publications: PubMed, Medline and EMBASE. The following search criteria were used: '(bone cysts OR intraosseous haematoma OR intraosseous haemorrhage) AND (afibrinogenaemia OR fibrinogen deficiency)'. The reference lists of the selected papers were searched for more relevant literature. In total, eight patients had bone cysts as complication of afibrinogenaemia and six of them suffered from pain in their extremities. Bone cysts were primarily located in the vicinity of the cortex or trabeculae in the diaphysis of the long bones, especially in the femora, tibiae and humeri. Some were regressive, probably due to reactive bone remodelling. A number of cysts were filled with serosanguinous fluid. It might be useful to check for bone cysts when patients with congenital afibrinogenaemia complain of 'rheumatic' pains in their extremities. Whole body magnetic resonance imaging is the diagnostic imaging technique of choice. Recurrent episodes of pain, but not radiological deterioration, appear to benefit from prophylactic therapy with fibrinogen concentrate.

Aneurysmal bone cyst: the role of cryosurgery as local adjuvant treatment.

BACKGROUND: Aneurysmal bone cysts (ABCs) are most often treated with intralesional surgery (curettage) and additional bone grafting. There is debate on whether or not to use adjuvant therapy to decrease the local recurrence rate. This study is done to assess the outcome of curettage and cryosurgery as a treatment of ABC. METHODS: We analyzed 80 consecutive cases of ABC treated with curettage and cryosurgery. Patients were followed minimal 24 months after surgery (average 55 months, range 24-122 months) with physical examination and radiographs. Functional outcome was evaluated using the musculoskeletal tumor society score (MSTS). RESULTS: The 80 patients were all treated with curettage and cryosurgery. Additional bone grafting was used in 73 patients, osteosynthesis in 12 and spondylodesis in 1 patient. Four local recurrences were found in this study, a recurrence rate of 5%. All local recurrences were treated successfully with curettage and cryosurgery again 7-33 months after the initial surgery. Postoperative one fracture, one wound infection, and three transient nerve palsy occurred. The average MSTS score was 29.2 at follow-up. CONCLUSIONS: The use of cryosurgery as adjuvant therapy results in a lower local recurrence rate when compared to other publications for the treatment of ABC and excellent functional results.

Promises and challenges of positron emission tomography for assessment of sarcoma in daily clinical practice.

A correct histological diagnosis, careful staging and detection of tumour response to treatment are all crucial in the management of sarcomas. Imaging is important in all of these stages. Sarcomas have distinct biological and treatment-related features posing challenges for imaging. For example, size measurements may not adequately reflect response rates. Techniques which can measure tissue function rather than generate merely anatomical data such as positron emission tomography (PET) are rapidly gaining interest. We discuss the importance of imaging in different stages of patient management, emphasising the unique characteristics of sarcoma. Furthermore, we discuss the potential of PET for the various indications, focussing on therapy evaluation.

Oncological and functional results of cryosurgical therapy of enchondromas and chondrosarcomas grade 1.

BACKGROUND AND OBJECTIVES: Cryosurgery using liquid nitrogen is used as adjuvant treatment after intralesional resection of bone tumours to induce cell death. It is applied to enlarge the oncological margins of resection and to reduce the local recurrence rate. The objective of this study is to analyze the oncological and functional results. METHODS: We studied the oncological and functional results of curettage and cryosurgery in 123 patients with 130 tumors. There were 75 enchondromas and 55 chondrosarcomas grade 1. The minimal follow-up period for all patients was 2 years (range 24-119 months). RESULTS: During follow-up one local recurrence of an active enchondroma and one local recurrence of an aggressive enchondroma occurred. They were treated with curettage and cryosurgery again. Both patients were disease-free at minimum of 3 years follow-up. No local recurrences after treatment of chondrosarcoma grade 1 were seen. Functional scores, according to the MSTS scoring system, showed an average score of 28 points (94%) at 2 years follow-up. Post-operative fractures were seen in 18 patients (14%). CONCLUSIONS: Curettage and cryosurgery for enchondroma and chondrosarcoma grade 1 has excellent oncological and functional results. The post-operative management has been adjusted to reduce the number of fractures.

Assessment of mandibular invasion of squamous cell carcinoma by various modes of imaging: constructing a diagnostic algorithm.

The aim of this study was to determine the optimal combination of preoperative examination methods to predict mandibular invasion by squamous cell carcinoma of the oral cavity. Data were gathered prospectively but evaluated retrospectively. The preoperative results of clinical examination, conventional radiography, bone single photon emission computed tomography (SPECT), computed tomography and magnetic resonance imaging were compared to the histological results of resection specimens from 67 patients with tumours, adjacent or fixed to the mandible, histologically confirmed as squamous cell carcinoma. The examination methods with acceptable sensitivity and specificity were selected and diagnostic algorithms were constructed using all possible combinations. The preferred diagnostic algorithm was found to be either computed tomography or magnetic resonance imaging, followed by a bone SPECT in cases where the first scan is negative. A negative bone SPECT rules out mandibular invasion (100% sensitivity). This algorithm accurately predicted mandibular invasion in 85% of the patients, without yielding false negative results. In this study group, application of such an algorithm would have resulted in a reduction of the number of unnecessary mandibular resections by 50%. The suggested, preferred, diagnostic algorithm shortens the preoperative screening process, avoiding unnecessary costs, as well as considerably reducing the number of unnecessary mandibular resections.

Current imaging concepts in pediatric osteomyelitis.

The diagnosis of osteomyelitis remains a difficult diagnostic dilemma. In this article, which is particularly aimed at those whose practice does not include a large paediatric population, we review the pathophysiology of paediatric osteomyelitis and contrast it with the available imaging modalities. We examine the role of the radiologist as well as the usefulness of each modality. Secondly, we review the different clinical scenarios such as acute, subacute and chronic, as well as specific forms of osteomyelitis; the latter includes subacute chronic ostemyelitis, toxic synovitis, spondylodiscitis as well as the congenital inflammatory disorders such as rubella and syphylis. The most useful imaging findings to look for and their significance are assessed and we evaluate their usefulness in each case. Close cooperation between clinicians and imagers remains the key to early and adequate diagnosis of paediatric osteomyelitis.