Y. Dohi

Prospective Outcomes of Comminuted Periarticular Metacarpal and Phalangeal Fractures Treated Using a Titanium Plate System

PURPOSE The purpose of this study was to prospectively evaluate clinical results for open reduction and internal fixation of unstable metaphyseal fractures of the metacarpal and phalangeal bones using a miniature titanium plate. METHODS Fifty-one consecutive patients with periarticular fractures with metaphyseal comminution and displacement were enrolled. Intra-articular involvement with a split or depression fracture was identified in 22 hands. Minimum follow-up was 1 year. There were 37 male and 14 female patients; average age was 38 years (range, 14-63). Of the 51 fractures, 15 were open; 8 of these had additional soft tissue injury, involving neurovascular injury in 4 and extensor tendon injury in 6. The average duration from injury to surgery was 6 days (range, 2-40 days). RESULTS Bone union was successfully achieved in all patients over an average period of 2.6 months. The final range of total active motion (%TAM) was excellent (>85%) for 26, good (70%-84%) for 17, fair (50%-69%) for 5, and poor (<49%) for 3. Postoperative complications occurred in 5 patients, including fracture redisplacement in 2, a collapse or absorption of the condylar head in 2, and superficial infection due to hardware exposure in one. Subsequently, 2 of these patients had malrotation deformities or osteoarthritic changes in the injured finger. Plates were removed in 30 cases, and additional surgery was required in 20 cases. Postoperative grip strength averaged 87% of the contralateral side. Statistical analysis revealed that patient age was significantly correlated with %TAM of the injured finger at 1-year follow-up (p < .01), and intra-articular (p < .05) and phalangeal bone (p < .01) involvement, as well as associated soft tissue injury (p < .05), significantly affected the range of finger motion. CONCLUSIONS Despite the technical demands of plating for comminuted metacarpal and phalangeal fractures, the low-profile titanium plate system was highly effective in maintaining anatomic reduction. The postoperative complication rate was relatively low, and the objective outcomes approached a reasonable level at 1-year follow-up. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.

Al2O3 doped apatite‐wollastonite containing glass ceramic provokes osteogenic differentiation of marrow stromal stem cells

Fresh marrow cells were obtained from femora of Fischer rats and cultured in a medium containing 15% fetal calf serum (FCS) until confluence. After trypsinization, cells were subcultured at a cell density of 100 x 10(3)/35-mm well in the presence of FCS, beta-glycerophosphate, and ascorbic acid phosphate on four different culture substrata. The period of subculture was 2 weeks; the substrata used were the culture dish, apatite-wollastonite containing glass ceramic (AW), hydroxyapatite coated AW (HA/AW), and Al2O3 doped AW (Al/AW). The HA coating was attained by the incubation of AW in simulated physiological solution. The glass matrix of AW and HA/AW contained MgO, CaO, P2O5, and SiO2; Al/AW contained Al2O3 in addition to these components. The subculture on Al/AW substratum showed many alkaline phosphatase (ALP) positive nodules and the highest ALP activity. On a Northern blot analysis the housekeeping gene of beta-actin mRNA was evenly detected from the cells cultured on all substrata; however, bone-specific osteocalcin mRNA was only detected from the cells on Al/AW. These results indicate that Al/AW provokes the osteoblastic differentiation of marrow stromal stem cells.

Reverse midpalmar island flap transfer for fingertip reconstruction.

Significant soft tissue defects of the fingertip with exposure of tendon or bone represent a challenging problem when homodigital or heterodigital artery island flaps are not available. In an attempt to resolve this problem, 15 patients with fingertip injuries involving palmar skin defects or amputation were treated with a vascularized flap transfer from the midpalmar area. A 2.5 x 1.5 to 4.5 x 2 cm flap from the radial or distal aspect of the midpalm, pedicled on the terminal branch of the superficial palmar arch or common/proper palmar digital artery and vein, was transferred in a retrograde fashion to cover the skin and soft tissue defects of the finger. All the flaps survived without complications. Moving two-point discrimination in the flap averaged 6 mm in patients who underwent sensory flap transfer. We concluded that vascularized skin flaps from the radial or distal aspects of the midpalm offer a good alternative option for the reconstruction of fingertip palmar skin and soft tissue defects.

Spectrocolorimetric evaluation of repaired articular cartilage after a microfracture

BackgroundIn clinical practice, surgeons differentiate color changes in repaired cartilage compared with surrounding intact cartilage, but cannot quantify these color changes. Objective assessments are required. A spectrocolorimeter was used to evaluate whether intact and repaired cartilage can be quantified.FindingsWe investigated the use of a spectrocolorimeter and the application of two color models (L* a* b* colorimetric system and spectral reflectance distribution) to describe and quantify articular cartilage. In this study, we measured the colors of intact and repaired cartilage after a microfracture. Histologically, the repaired cartilage was a mixture of fibrocartilage and hyaline cartilage. In the L* a* b* colorimetric system, the L* and a* values recovered to close to the values of intact cartilage, whereas the b* value decreased over time after the operation. Regarding the spectral reflectance distribution at 12 weeks after the operation, the repaired cartilage had a higher spectral reflectance ratio than intact cartilage between wavelengths of 400 to 470 nm.ConclusionThis study reports the first results regarding the relationship between spectrocolorimetric evaluation and the histological findings of repair cartilage after a microfracture. Our findings demonstrate the ability of spectrocolorimetric measurement to judge the repair cartilage after treatment on the basis of objective data such as the L*, a* and b* values and the SRP as a coincidence index of the spectral reflectance curve.

Quantitative Analysis of Bone Formation in the Composites of Cultured Marrow Cells and Hydroxyapatite by X-Ray Computed Tomography

When porous hydroxyapatite (HA) ceramics are combined with cultured marrow mesenchymal stem cells or with differentiated osteoblasts, the composites can show in vivo osteogenic potential. We attempted to analyze this potential by using high resolution X-ray computed tomography (CT). The computer system can visualize the three-dimensional (3D) structure of the ceramics and also measure the pore size, diameter and volume as well as the newly formed bone in the pores areas. In this study, rat marrow mesenchymal stem cells were cultured in pore areas of the HA ceramics for two weeks to force the cells into osteoblastic lineage. The HA ceramics with the cultured cells were then implanted at subcutaneous sites of syngeneic rats. Histological analysis confirmed the in vivo bone formation in pore areas of the implanted HA ceramics. By using the 3D CT analysis of the implants, extensive bone formation was seen in outer pore areas compared with that in inner pore areas and the volume of the newly formed bone increased as time passed. These results evidenced the osteogenic potential of the HA ceramics loaded with cultured cells which can be evaluated by non-destructive analysis using X-ray computed tomography. Introduction We have reported the in vivo bone forming capability of bone marrow cells when combined with porous ceramics. Not only fresh [1,2] but also cultured marrow cells [3] can show the bone formation. It is believed that the osteogenic potential can be attributed to the existence of mesenchymal stem cells in the bone marrow [4]. The number of the stem cells can be expanded and further differentiated into osteoblasts in culture condition [5,6]. The cultured stem cells [3] or osteoblasts [7] in porous HA can show in vivo osteogenic potential. The potential can be estimated by conventional histological and biochemical analyses (measurements of alkaline phosphatase activity and osteocalcin contents at protein and gene expression levels). Although, the methods needs cutting/ homogenization process of the implants and thus, the methods are destructive. Purpose of this study is to estimate the osteogenic potential by non-destructive analysis using X-ray computed tomography [8]. Materials and Methods Marrow cells were obtained from the femoral shafts of 7-week-old male Fischer 344 rats and cultured in the medium consisted of an Eagle minimal essential medium (MEM) containing 15% fetal bovine serum and antibiotics in a T-75 flask. During the culture, non-adherent cells were washed off leaving the adherent cell layer (marrow mesenchymal cells) [5]. After 1 week in the primary culture, confluent cells were harvested after treatment with 0.25% trypsin solution and condensed at the density of 10 cell/ml. The coralline HA ceramic(Interpore 200; disk shape of 5mm diameter / 2mm thickness and pore diameter of 200um: Interpore International, Irvine, California) were soaked in the cell suspension for two hours, then the composites were subcultured for 2 weeks in the medium supplemented with Key Engineering Materials Online: 2003-05-15 ISSN: 1662-9795, Vols. 240-242, pp 615-618 doi:10.4028/www.scientific.net/KEM.240-242.615

Reliability of the iPad Measurement for Range of Dart-Throwing Motion

Hypothesis: The dart-throwing motion (DTM) is functionally very important movement from radial extension to ulnar flection of the wrist and the anatomical and biomechanical futures have been demonstrated experimentally. Clinically, there is the only report to be published to describe the method of goniometric measurement for DTM but the reliability of measurement has not been evaluated. We hypothesized that our DTM measurement method using a tablet device and a simple jig can be a more reliable method. Methods: Participants were 10 healthy volunteers for assessing intrarater reliability and 3 examiners for interrater reliability. Range of extension-flexion and DTM were evaluated. Participants moved their wrist in each motion plane on a flat table. During the DTM measurements, their hand was fixed to an isosceles right triangle jig and kept their wrist rotation 45° obliquely on the table, so they moved their wrist freely in a DTM plane on the table. Photo images at each maximum wrist position from right overhead were recorded using a tablet device and the angle was measured by goniometric software launched on the device. Reference points were marked on participant’s skin before recording images according to our protocol. Intraclass correlation coefficients (ICC) were compared to determine intrarater and interrater reliability, using the SPSS software package (P < .05). Results: All results are shown in Table 1. According to the guideline provided by Landis and Koch, there was substantial intraobserver (ICC = .67, .71) and interobserver (ICC = .77, .72) in flexion and extension, respectively. We observed almost perfect intraobserver (ICC = .92) and substantial interobserver (ICC = .79) in ulnar flexion and substantial intraobserver (ICC = .62) in radial extension in a DTM plane. There was moderate interobserver (ICC = .59) in radial extension in a DTM plane. Conclusion: The results of the study indicate that the measuring method of the range of motion by use of tablet device can maintain fixed reliability or more. Intrarater and interrater reliability of our method of measurement for DTM compares favorably with conventional flexion-extension motion. The recording of photo image can transform a 3-dimensional object to the plane figure and make the measurement easy.

Osteogenic Potential of Tissue Engineered Bone by Combination of Marrow Mesenchymal Cells and Cultured Bone/Ceramic Constructs

Introduction: Osteogenesis occurs in porous hydroxyapatite (HA) when HA blocks combined with marrow mesenchymal cells are grafted in vivo. In vitro bone formation occurs in HA pores when HA combined with marrow cells is cultured in osteogenic medium containing dexamethasone. Cultured bone/HA constructs possess higher osteogenic ability when they are grafted in vivo. Marrow mesenchymal cells (MSCs) contain many stem cells which can generate many tissue types. In the present study, we investigated osteogenic potential of cultured bone/HA combined with MSCs. Materials and Methods: Marrow cells were obtained from the femoral bone shaft of male Fischer 344 rats (7 weeks old), and were cultured in T-75 flasks. Primary cultured cells were trypsinized and combined with porous HA (5x5x5 mm, Interpore 500). The composites were subcultured in osteogenic medium containing dexamethasone. One tenth of primary cells were transferred into new T-75 flasks containing standard medium. After 2 weeks, MSCs were trypsinized, combined with cultured-bone/HA constructs, and prepared for implantation. MSC/cultured-bone/HA constructs, cultured bone/HA constructs, and HA alone were subcutaneously implanted into syngeneic rats. These implants were harvested at 2 or 4 weeks post-implantation, and prepared for histological and biochemical analyses. Results: Alkaline phosphatase activity and osteocalcin content of MSC /cultured bone/HA constructs were much higher than those of cultured bone/HA constructs at 2 and 4 weeks post-implantation. Histological examination supported these findings. Discussion and Conclusion: MSCs show high ability of cell proliferation. In addition, MSCs can generate new blood vessels which would support regeneration of bone tissue. Here, we suggested that MSCs could promote osteogenesis. We also showed that excellent engineered bone tissue could be fabricated by combining MSCs and cultured bone derived from dexamethasone-treated MSC culture.

Bone Regeneration from Frozen Marrow Mesenchymal Cells/Recombinant Human Bone Morphogenetic Protein/Hydroxyapatite Transplantation

Introduction: Marrow mesenchymal cells contain stem cells and can regenerate tissues. We previously reported the clinical application of autologous cultured bone to regeneration therapy. However, in cases with low numbers of active cells, culture is often unsatisfactory. If frozen marrow cells retain their osteogenic potential, we could clinically use them in regeneration therapy as alternatives to high active cells obtained from youngsters. Here, we examined osteogenic potential of frozen human mesenchymal stem cells in combination with recombinant human bone morphogenetic protein (rhBMP) using biochemical and histological analyses. Method: Marrow fluid was aspirated from the human iliac bone of a 46-year-old man with lumbar canal stenosis during surgery. Two weeks after primary culture in standard medium, bone marrow mesenchymal stem cells (BMSCs) were trypsinized for the preparation of a cell suspension, and cells were concentrated to 106 cells/ml by centrifugation. Cells were kept at – 80 °C until use. To impregnate porous hydroxyapatite (HA) with rhBMP, 1 3g rhBMP/20 3l 0.1 % trifluoroacetic acid was applied on HA, and then desiccated under vacuum. In the present study, we used 4 subgroups: BMSC/rhBMP/HA, BMSC/HA, rhBMP/HA, and HA only. HA constructs from the 4 subgroups were implanted at subcutaneous sites on the back of 5-week-old nude mice (BALB/cA Jcl-nu). Eight weeks after implantation, implanted HA constructs were harvested, and biochemical and histological analyses were performed. Alkaline phosphatase activity (ALP) and human osteocalcin (hOs) levels were measured. Results and Discussion: ALP activity and hOs in the BMSC/BMP/HA subgroup were 2 or 3 times that in the BMSC/HA subgroup. Histological analysis showed that significant bone formation was observed in these two subgroups, and supported biochemical data. However, in the BMP/HA and HA only subgroups, significant bone formation could not be detected histologically nor biochemically. These results indicated that a combination of rhBMP and BMSCs, and only with a minimal amount of 1 3g rhBMP, allowed successful generation of human bone. In the human body, rhBMP in the order of milligrams is necessary for bone formation. However, by combining BMSCs, HA and rhBMP, only a small amount of rhBMP was needed to dramatically enhance osteogenic potential. As we reported here, cryopreserved BMSCs also showed high osteoblastic activity. In conclusion, this study provided histological and biochemical evidence that combination of cryopreserved BMSCs, BMP, and porous HA could enhance osteogenic potential.