Pseudo-ataxia due to Osteoid Osteoma.

Background: Ataxia is diagnosed by typical features on examination suggestive of a cerebellar etiology and can invoke extensive diagnostic testing. Osteoid osteomas (OOs) are benign bone tumors of the lower limbs that occasionally present with focal neurological signs. Case Report: A 3-year-old male presented with apparent progressive gait ataxia and non-specific leg pain. Initial imaging was unremarkable. However, 12 months later, a lesion was identified in the distal right femur, which was found to be an OO. The gait disorder and pain resolved after surgery. Discussion: This case highlights the challenges of diagnosing a gait disorder in young children.

Screening and referral for children with physical disabilities.

The clinical care of children with physical disabilities is a major priority for paediatricians and paediatric orthopaedic surgeons. Cerebral palsy (CP) is the prototypical condition and remains the most common cause of physical disability in developed countries. The incidence is approximately 2 per 1000 live births, translating to between 600 and 700 new children per annum in Australia, with approximately 34 000 children and adults currently living with CP. This figure is predicted to rise inexorably over the next 20 years. The care of children with physical disabilities, including those with CP, is usually coordinated by paediatricians, general practitioners and allied health teams including physiotherapists, with input from paediatric orthopaedic surgeons when appropriate. The emphasis in care for children with CP has moved from 'reactive' to 'proactive'. In the past, children are often referred when symptomatic, for example when a hip dislocation had occurred and became painful. The emphasis now is on coordinated, multidisciplinary care in which musculoskeletal manifestations of disability are identified by screening programmes. Systematic screening, especially when population-based and linked to a register, avoids children getting 'lost in the system'. Early and more effective interventions may be offered for the prevention of contractures, dislocation of the hip and spinal deformities. In this review, we will focus on the assessment of gait in children with physical disabilities, and monitoring for hip and spine deformity.

Computer-assisted surgical correction of an antebrachial deformity in a dog.

OBJECTIVE: To report the use of three dimensional (3D) computed tomographic (CT) imaging, computer simulation and rapid prototype modelling to aid surgical correction of a complex antebrachial deformity in a dog. METHODS: A six-year-old, 13 kg spayed female Chihuahua crossbreed dog was presented for worsening forelimb gait and exercise intolerance. Both forelimbs had gross angular limb deformity with carpal hyper-flexion, valgus and radial procurvatum. Surgical planning from radiographs was problematic therefore CT data were used to generate 3D reconstructions of the antebrachium. Using imaging software we then quantified the nature of the deformity using a previously unreported method based on the centre of rotation of angulation as a 3D model. Computer simulated closing of the virtual wedge osteotomy was then performed as proof of concept. A stereolithographic model complete with osteotomy axes, was then created in plastic using a rapid prototyping machine. Oscillating saw guides were fabricated in polymethylmethacrylate and cold sterilised. A closing wedge osteotomy with de-rotation was performed and stabilised with a pre-contoured dynamic compression plate. At the three- and six-month follow-up examinations there was improved weight-bearing and cosmetic appearance. CONCLUSIONS: Computer assistance was valuable for locating and quantifying this antebrachial deformity and conceptualising the corrective surgery. The results of our study suggest that rapid prototyping can be used to create models and saw guides to simplify one-stage corrective osteotomies and more accurately treat angular limb deformity.

[Rupture of the extensor carpi radialis tendon in two horses]. / Ruptur der Sehne des Musculus extensor carpi radialis bei zwei Pferden.

Symptoms, diagnosis, therapy and clinical outcome of 2 horses which acquired a complete rupture of the extensor carpi radialis tendon by accident are described. The resulting gait abnormalities are very typical, so that the problem can be diagnosed already by clinical examination. With the help of ultrasound the diagnosis could be confirmed and the degree of damage quantified. The open wounds in the carpal region were surgically treated in a standing position and the limbs of both horses were kept under a splint bandage for 6 to 8 weeks. Prognosis in these cases was good, as both horses returned within 6 months back to their previous work.

Fenestration of vertebral artery at the craniovertebral junction in Down syndrome: a case report.

STUDY DESIGN: Case report of a Down syndrome patient with right vertebral artery fenestration and abnormalities of the craniovertebral junction. OBJECTIVES: Describe the utility of 3-dimensional computed tomography angiography for evaluating vertebral artery anomalies before surgery. SUMMARY OF BACKGROUND DATA: Previous reviews evaluating catheter angiograms identified various anomalies of vertebral artery at the craniovertebral junction. The frequency of vertebral artery anomalies is increased in patients having osseous anomalies at the craniovertebral junction. Down syndrome is associated with a high incidence of bone abnormalities at the craniovertebral junction, but there have been no published reports of vertebral artery anomalies per se at the craniovertebral junction. METHODS: A 16-year-old woman with trisomy 21 presented with gait abnormalities and myelopathy in association with bone abnormalities at the craniovertebral junction, including hypoplastic odontoid and ossiculum terminale. Computed tomography angiography showed that right vertebral artery bifurcated after exiting the C2 transverse foramen with one branch passing through the C1 transverse foramen, whereas the other turned posteromedially and entered the spinal canal between C1 and C2. RESULTS: Occipito-C2 posterior fusion was performed with a rod and screw system. Intraoperatively, the course of the anomalous right vertebral artery was identified by Doppler angiography, and the surgical approach was modified to allow safe pedicle screw insertion while avoiding vertebral artery injury. After surgery, myelopathy resolved within 3 months. CONCLUSIONS: Before corrective surgery of craniovertebral junction anomalies in patients with Down syndrome, the possibility of vertebral artery anomalies associated with abnormal craniovertebral junction anatomy should be considered. With preoperative 3-dimensional computed tomography angiography, we can precisely identify the anomalous vertebral artery and modify the surgical approach to reduce the possible risk of intraoperative vertebral artery injury in advance.