Sinding-Larsen-Johansson syndrome with minimally displaced patellar sleeve avulsion fracture: a case report with multimodality approach and literature review.

Sinding-Larsen-Johansson syndrome is an osteochondrosis affecting the inferior pole of the patella. Most cases can be easily diagnosed with adequate clinical history, physical examination, and proper imaging, including conventional radiography, ultrasound, and magnetic resonance imaging. Differentiating this condition from patellar sleeve avulsion fractures is important, since treatment is frequently surgical in the latter. Overlap between these two conditions can also occur. We present a case of an 11-year-old boy, with Sinding-Larsen-Johansson syndrome on both knees and a minimally displaced acute patellar avulsion sleeve fracture of the left knee, which was treated conservatively.

International comparative study of low back pain care pathways and analysis of key interventions.

PURPOSE: Low back pain (LBP) is a major public health problem worldwide. Significant practice variation exists despite guidelines, including strong interventionist focus by some practitioners. Translation of guidelines into pathways as integrated treatment plans is a next step to improve implementation. The goal of the present study was to analyze international examples of LBP pathways in order to identify key interventions as building elements for care pathway for LBP and radicular pain. METHODS: International examples of LBP pathways were searched in literature and grey literature. Authors of pathways were invited to fill a questionnaire and to participate in an in-depth telephone interview. Pathways were quantitatively and qualitatively analyzed, to enable the identification of key interventions to serve as pathway building elements. RESULTS: Eleven international LBP care pathways were identified. Regional pathways were strongly organized and included significant training efforts for primary care providers and an intermediate level of caregivers in between general practitioners and hospital specialists. Hospital pathways had a focus on multidisciplinary collaboration and stepwise approach trajectories. Key elements common to all pathways included the consecutive screening for red flags, radicular pain and psychosocial risk factors, the emphasis on patient empowerment and self-management, the development of evidence-based consultable protocols, the focus on a multidisciplinary work mode and the monitoring of patient-reported outcome measures. CONCLUSION: Essential building elements for the construction of LBP care pathways were identified from a transversal analysis of key interventions in a study of 11 international examples of LBP pathways.

Pain at the knee: the Morel-Lavallée lesion, a case series.

Post-traumatic pain at the knee is a common clinical presentation with a wide and varied differential diagnosis. The Morel-Lavallée lesion (MLL) is a rare cause of pain at the knee, caused by post-traumatic shearing of the hypodermis from the underlying fascia. The space created can fill with blood, lymph and necrotic fat giving specific findings on ultrasound and magnetic resonance (MR) evaluation. Three different cases of patients diagnosed with the MLL surrounding the knee are presented, with clinical and radiological findings. The different treatment options will be evaluated. The MLL is a rare but important cause of post-traumatic pain at the knee. Clinical exam and history are mandatory in diagnosing an MLL. Ultrasound and MR examination are very helpful in assessing the diagnosis. Various treatment options, nonsurgical as well as surgical, seem to be effective and should be considered depending on presentation and duration.

ACTN3 (R577X) genotype is associated with fiber type distribution.

alpha-Actinin-3 is a Z-disc structural protein found only in type II muscle fibers. The X allele of the R577X polymorphism in the ACTN3 gene results in a premature stop codon and alpha-actinin-3 deficiency in XX homozygotes. Associations between the R577X polymorphism and the muscle-power performance of elite athletes have been described earlier. About 45% of the fiber type proportions are determined by genetic factors. The ACTN3 variant could be one of the contributing genes in the heritability of fiber type distribution through its interaction with calcineurin. The aim of this study was to quantify the association between the polymorphism and muscle fiber type distribution and fast-velocity knee extension strength. Ninety healthy young men (18-29 y) were genotyped for ACTN3 R577X. Knee extensor strength was measured isometrically (45 degrees ) and at different dynamic velocities (100-300 degrees /s) on a programmable dynamometer. Twenty-two XX and twenty-two RR subjects underwent a biopsy of the right vastus lateralis muscle. Fiber type composition was determined by immunohistochemistry. Homozygotes for the R allele show significantly higher relative dynamic quadriceps torques at 300 degrees /s, compared with XX carriers (P < 0.05). Fiber type characteristics differed significantly between the two genotype groups. The percentage surface and number of type IIx fibers were greater in the RR than the XX genotype group (P < 0.05), and alpha-actinin-3 protein content is systematically higher in type IIx compared with type IIa fibers (staining intensity ratio IIx to IIa = 1.17). This study shows that the mechanism, by which the ACTN3 polymorphism has its effect on muscle power, might rely on a control function of fiber type proportions.