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Purpose: To measure the biomechanical properties (maximum load, stiffness, and elongation) of the anterolateral ligament (ALL), gracilis, and iliotibial band (ITB) within the same subject. METHODS: Thirteen unpaired knees were used (7 women, 6 men). The donors had a mean age at death of 54 years (range: 37 to 70 years). The mechanical properties of two types of ALL grafts were evaluated: ITB and two-strand gracilis. The mechanical properties of ALL were also measured. Validated methods were used to perform the tensile tests to failure and to record the results. Student's t-test was used to compare the various samples. RESULTS: The maximum load to failure was 141 N (±40.6) for the ALL, 200.7 N (±48.7) for the gracilis, and 161.1 N (±27.1) for the ITB. Only the gracilis had a significantly higher failure load than ITB and ALL (P = .001 and P = .03). The stiffness was 21 N mm-1 (±8.2) for the ALL, 131.7 N mm-1 (±43.7) for the gracilis, and 39.9 N mm-1 (±6) for the ITB. The elongation at failure was 6.2 mm (±3.2) for the ALL, 19.9 mm (±6.5) for the gracilis, and 20.8 mm (±14.7) for the ITB. CONCLUSIONS: The gracilis had the highest maximum load to failure. The ITB's mechanical properties most closely resemble those of the ALL. CLINICAL RELEVANCE: The biomechanical properties of each potential ALL graft can be factored in when deciding which type of graft to use.

The purpose of this study was to analyse the learning curve and complication rate of the open Latarjet procedure. The first 68 Latarjet procedures performed by a single surgeon for chronic anterior shoulder instability were reviewed retrospectively. The standard open surgical technique was followed faithfully during each procedure. Post-operative complications were taken from patient medical records. Post-operative evaluation consisted of clinical and radiological assessments. The rate of early (

Homeostasis of the intervertebral disc relies on nutrient supply and waste clearance through the dense capillary network that is in contact with the cartilage endplate (CEP). We developed a micro-computerized tomography (micro-CT) method to quantify the marrow contact channel surface (MCCS) with the CEP and to validate the hypothesis according to which MCCS was correlated to the effective permeability of the vertebral endplate (VEP) and influenced by the mechanical stimuli. The influence of compression loading on local vascularization was investigated. Six 4-week-old skeletally immature pigs were instrumented with left pedicle screws and rod at both T5-T6 and L1-L2 levels to create asymmetrical spine tethers. After 3 months of growth, three cylindrical specimens of the VEP (one central and two lateral right and left) were obtained from both the instrumented and the control levels. We used a previously validated method for measuring permeability. Micro-CT analysis (resolution 12 mu m) yielded a gray-scale 2D-image of the discal end of each specimen converted into a binary 2D-image to derive the MCCS. Correlations between MCCS and effective permeability were assessed. Effective permeability and MCCS were significantly decreased compared to the control group especially on the tethered side (-41..5%, p = 0.004 and -52.5%, p = 0.0009, respectively). Correlations were significant and showed maximal value (r(2) = 0.430, p < 0.0001) on the tethered side involving maximal compressive loadings. Mechanical stimuli, due to unbalanced growth, altered the vascularization and the convective properties of the CEP. The cascade of mechanobiological events should offer perspectives for research on disc degeneration and attempted treatment. (C) 2010 Orthopaedic Research Society.

We compared disc hydration properties of adolescent idiopathic scoliosis before and 5 years after spinal fusion with an age-matched control group. We conducted a prospective MRI follow-up of 23 patients. Disc and nucleus volumes were reconstructed on T2 weighted sequence. In the scoliotic group, vd and vn were lower than control group, hydration ratio (Vn/Vd) was lower. After surgery, subjacent discs rehydrated. AIS induces a loss of IVD hydration. Surgical correction can reverse homeostasis disturbances related to spinal deformity.

Ideal surgical management of adolescent idiopathic scoliosis (AIS) aims for an optimal correction of the deformity while preserving mobility. An unbalanced rigid spine puts the mobile segment at higher risk of disk degeneration. The goal of our study is to clarify the long term outcome of AIS after spinal fusion.