Femoral Morphology Due to Impingement Influences the Range of Motion in Slipped Capital Femoral Epiphysis

Femoroacetabular impingement due to metaphyseal prominence is associated with the slippage in patients with slipped capital femoral epiphysis (SCFE), but it is unclear whether the changes in femoral metaphysis morphology are associated with range of motion (ROM) changes or type of impingement. We asked whether the femoral head-neck junction morphology influences ROM analysis and type of impingement in addition to the slip angle and the acetabular version. We analyzed in 31 patients with SCFE the relationship between the proximal femoral morphology and limitation in ROM due to impingement based on simulated ROM of preoperative CT data. The ROM was analyzed in relation to degree of slippage, femoral metaphysis morphology, acetabular version, and pathomechanical terms of "impaction” and "inclusion.” The ROM in the affected hips was comparable to that in the unaffected hips for mild slippage and decreased for slippage of more than 30°. The limitation correlated with changes in the metaphysic morphology and changed acetabular version. Decreased head-neck offset in hips with slip angles between 30° and 50° had restricted ROM to nearly the same degree as in severe SCFE. Therefore, in addition to the slip angle, the femoral metaphysis morphology should be used as criteria for reconstructive surger

Femoral Morphology Due to Impingement Influences the Range of Motion in Slipped Capital Femoral Epiphysis

Femoroacetabular impingement due to metaphyseal prominence is associated with the slippage in patients with slipped capital femoral epiphysis (SCFE), but it is unclear whether the changes in femoral metaphysis morphology are associated with range of motion (ROM) changes or type of impingement. We asked whether the femoral head-neck junction morphology influences ROM analysis and type of impingement in addition to the slip angle and the acetabular version. We analyzed in 31 patients with SCFE the relationship between the proximal femoral morphology and limitation in ROM due to impingement based on simulated ROM of preoperative CT data. The ROM was analyzed in relation to degree of slippage, femoral metaphysis morphology, acetabular version, and pathomechanical terms of “impaction” and “inclusion.” The ROM in the affected hips was comparable to that in the unaffected hips for mild slippage and decreased for slippage of more than 30°. The limitation correlated with changes in the metaphysic morphology and changed acetabular version. Decreased head-neck offset in hips with slip angles between 30° and 50° had restricted ROM to nearly the same degree as in severe SCFE. Therefore, in addition to the slip angle, the femoral metaphysis morphology should be used as criteria for reconstructive surgery

Collagen metabolism of human osteoarthritic articular cartilage as modulated by bovine collagen hydrolysates. PLoS One 2013

Abstract Destruction of articular cartilage is a characteristic feature of osteoarthritis (OA). Collagen hydrolysates are mixtures of collagen peptides and have gained huge public attention as nutriceuticals used for prophylaxis of OA. Here, we evaluated for the first time whether different bovine collagen hydrolysate preparations indeed modulate the metabolism of collagen and proteoglycans from human OA cartilage explants and determined the chemical composition of oligopeptides representing collagen fragments. Using biophysical techniques, like MALDI-TOF-MS, AFM, and NMR, the molecular weight distribution and aggregation behavior of collagen hydrolysates from bovine origin (CH-AlphaH, Peptan TM B 5000, Peptan TM B 2000) were determined. To investigate the metabolism of human femoral OA cartilage, explants were obtained during knee replacement surgery. Collagen synthesis of explants as modulated by 0-10 mg/ml collagen hydrolysates was determined using a novel dual radiolabeling procedure. Proteoglycans, NO, PGE 2 , MMP-1, -3, -13, TIMP-1, collagen type II, and cell viability were determined in explant cultures. Groups of data were analyzed using ANOVA and the Friedman test (n = 5-12). The significance was set to p#0.05. We found that collagen hydrolysates obtained from different sources varied with respect to the width of molecular weight distribution, average molecular weight, and aggregation behavior. None of the collagen hydrolysates tested stimulated the biosynthesis of collagen. Peptan TM B 5000 elevated NO and PGE 2 levels significantly but had no effect on collagen or proteoglycan loss. All collagen hydrolysates tested proved not to be cytotoxic. Together, our data demonstrate for the first time that various collagen hydrolysates differ with respect to their chemical composition of collagen fragments as well as by their pharmacological efficacy on human chondrocytes. Our study underscores the importance that each collagen hydrolysate preparation should first demonstrate its pharmacological potential both in vitro and in vivo before being used for both regenerative medicine and prophylaxis of OA

Compositional differences of collagen hydrolysates as determined by MALDI-TOF-MS.

<p>Mass spectra obtained in the (<b>A–C</b>) linear and (<b>D–F</b>) reflector mode reveal differences between (<b>A,D</b>) CH-Alpha®, (<b>B,E</b>) RDH, and (<b>C,F</b>) RDH-N with respect to peptide composition, as represented by the molecular weight distribution of the peptides, and the average molecular weight of each collagen hydrolysate preparation.</p

Effect of collagen hydrolysates on the collagen synthesis of OA cartilage.

<p>Incorporation of [³H]-proline and [¹⁴C]-proline into collagen of human cartilage explants was determined by measuring the radioactivity found in hydroxyproline. The [¹⁴C/³H]-incorporation ratio was then calculated and is expressed as percent of untreated control (100%) in the presence of 0.1, 0.5, 1, 2, and 10 mg/ml of RDH, RDH-N, or CH-Alpha®. Each experiment was done with explants removed from the lateral condyle of 6 patients graded with a Collins score of <1.5 and another 6 patients who presented lateral condyles with a Collin score between 1.5 and 3. Thus, explants from a total of 12 patients were used. Data shown are the mean±standard deviation (N = 12). Statistically significant different from untreated controls: **0.001</p

Three-dimensional AFM picture (top) and NMR-TOCSY spectra (middle, bottom) of collagen hydroylsates.

<p>The AFM picture (Fig. 2 top) shows the amorphous crystal-like structures in the presented 25 square micrometer area (0 to 5 micrometer) with a high resolution in the third dimension (0 to 150 nanometer), demonstrating that no higher-ordered collagen structures (eg, triple-helical collagen fragments) are present in the collagen hydrolysate preparation (RDH) from Rousselot. The highly resolved proton-NMR signals are displayed along the F1 and the F2 axes according to their ppm values (Fig. 2 middle and bottom). F1 is frequency axis one, F2 is the second frequency axis. The ppm values on both frequency axes correspond to the ppm values of the one-dimensional NMR spectrum. Depending on the relation of the magnetization transfer (via the bonds: TOCSY, via space: NOESY), an assignment of the signals to the protons is possible and thus leads to a characteristic fingerprint pattern of the collagen hydrolysate investigated (Fig. 2 middle and bottom). The TOCSY spectra (Fig. 2 middle and bottom) show, for example, one obvious difference in their signal patterns–namely, the characteristic cross-peak at F1: 1.5 ppm/F2: 7.2 ppm, highlighted as a grey circle in the TOCSY spectrum of RDH (Fig. 2 middle), is missing in the TOCSY spectrum of RDH-N (Fig. 2 bottom). This observation makes it clear that the fragments that belong to this cross-peak are missing in the sample RDH-N (Fig. 2 bottom). Thus, one change in the cross-peak signal pattern is already enough to distinguish between different collagen hydrolysates.</p

Concentration-dependent effect of collagen hydrolysates on the synthesis and/or release of MMP-1, MMP-3, and MMP-13.

<p>MMPs were determined within nutrient media of cultured human articular cartilage. Following stabilization of explant metabolism for 4–6 days, explants were treated for additional 6 days with 0–10 mg/ml collagen hydrolysate. MMPs were determined with ELISA, and data are expressed as mean±standard deviation (N = 5). Statistically significant different from untreated controls: *0.01</p