Peter A Nolte

Publications of Peter A Nolte

• Tuberositas osteotomy for total knee arthroplasty: a review of the literature.

  Authors: Christian B L Zonnenberg, Lukas A Lisowski, Michel P J van den Bekerom, Peter A Nolte

  The journal of knee surgery. 09/2010; 23(3):121-9.

  Tibial tubercle osteotomy (TTO) is a well-known technique for improving exposure in difficult total knee arthroplasty (TKA). We have performed a review of the literature concerning this procedureTibial tubercle osteotomy (TTO) is a well-known technique for improving exposure in difficult total knee arthroplasty (TKA). We have performed a review of the literature concerning this procedure with the purpose of evaluation using the clinical results and complication rates in primary and revision TKA using TTO. We conducted a search limited to the following databases: PubMed/Medline, Cochrane Database of Systematic Reviews, Cochrane Clinical Trial Register, and Embase. These were searched from 1979 to May 2009 to identify studies relating to the primary and revisions of TKA using a tuberositas osteotomy. Eighteen studies met the inclusion criteria including 823 cases. In 762 cases, a medial TTO was performed. Most patients had an improved knee function after TKA. Proximal migration of the osteotomized site (n=18), TTO-related pain (n=17), and avulsion fractures of the tubercle (n=13) were the most reported complications of this technique. TTO is a relatively safe and reproducible procedure for the enhancement of surgical exposure in difficult primary or revision TKA. Serious complications related to TTO were reported in 8 to 9% of all cases. Future studies should compare different fixation methods in a prospective randomized controlled way.

• Low-intensity pulsed ultrasound affects RUNX2 immunopositive osteogenic cells in delayed clinical fracture healing.

  Authors: Sjoerd Rutten, Peter A Nolte, Clara M Korstjens, Jenneke Klein-Nulend

  Bone. 08/2009;

  INTRODUCTION: Osteogenic cell proliferation and differentiation play an important role in adequate fracture healing, and is target for osteoinductive therapies in delayed fracture healing. The aim ofINTRODUCTION: Osteogenic cell proliferation and differentiation play an important role in adequate fracture healing, and is target for osteoinductive therapies in delayed fracture healing. The aim of this study was to investigate whether low-intensity pulsed ultrasound enhances fracture healing at the tissue level in patients with a delayed union of the osteotomized fibula through an effect on the presence of RUNX2 immunopositive osteogenic cells. The effect was studied in both atrophic and hypertrophic delayed unions. MATERIALS AND METHODS: Biopsies were obtained from 6 female and 1 male patient (age 43-63) with a delayed union of the osteotomized fibula after a high tibial osteotomy treated for 2-4 months with or without low-intensity pulsed ultrasound in a randomized prospective double-blind placebo-controlled trial. Immunolocalization of RUNX2 protein was performed to identify osteogenic cells. Histomorphometrical analysis was performed to determine the number of cells expressing RUNX2 located within and around the newly formed woven bone at the fracture end (area of new bone formation), and up to 3 mm distant from the fracture end. RESULTS: Cells expressing RUNX2 were present in all histological sections of control and low-intensity pulsed ultrasound-treated bone evaluated. Within the area of new bone formation, RUNX2 immunopositive cells were found in the undifferentiated soft connective tissue, at the bone surface (presumably osteoblasts), and within the newly formed woven bone. Low-intensity pulsed ultrasound treatment of fibula delayed unions significantly reduced the number of RUNX2 immunopositive cells within the soft connective tissue at the fracture ends, whereas the number of RUNX2 immunopositive cells at the bone surface was not affected. The number of RUNX2 immunopositive cells was similar for the atrophic and hypertrophic delayed unions. CONCLUSIONS: Immunolocalization of RUNX2 positive cells in delayed unions of the fibula reveals that delayed clinical fracture healing does not result in impairment of osteogenic cell proliferation and/or differentiation at the tissue level, even if delayed unions are clinically regarded as atrophic. Reduced number of osteogenic RUNX2 immunopositive cells within the soft connective tissue, and unchanged number of RUNX2 immunopositive cells at the bone surface, implicate that low-intensity pulsed ultrasound does not increase osteogenic cell presence, but likely affects osteogenic cell differentiation.

• Osteocyte morphology in human tibiae of different bone pathologies with different bone mineral density - is there a role for mechanosensing?

  Authors: Ruud P van Hove, Peter A Nolte, Aviral Vatsa, Cornelis M Semeins, Philip L Salmon, Theo H Smit, Jenneke Klein-Nulend

  Bone. 05/2009;

  Matrix strains due to external loading are different in bones of different pathologies with different bone mineral density (BMD), and are likely sensed by the osteocytes, the putative boneMatrix strains due to external loading are different in bones of different pathologies with different bone mineral density (BMD), and are likely sensed by the osteocytes, the putative bone mechanosensors. The mechanosensitivity of osteocytes appears to be strongly influenced by their morphology. In this study, we explored the possibility that osteocyte morphology might play a role in various bone pathologies with different BMD. Confocal laser scanning microscopy and nano-CT were used to quantitatively determine 3D morphology and alignment of osteocytes and osteocyte lacunae in human proximal tibial bone with relatively low (osteopenic), medium (osteoarthritic), and high (osteopetrotic) BMD.Osteopenic osteocytes were relatively large and round (lengths 8.9:15.6:13.4 mum), osteopetrotic osteocytes small and discoid shaped (lengths 5.5:11.1:10.8 mum), and osteoarthritic osteocytes large and elongated (lengths 8.4:17.3:12.2 mum). Osteopenic osteocyte lacunae showed 3.5 fold larger volume and 2.2 fold larger surface area than osteoarthritic lacunae, whereas osteopetrotic lacunae were 1.9 fold larger and showed 1.5 fold larger surface area than osteoarthritic lacunae. Osteopetrotic osteocyte lacunae had lower alignment than osteopenic and osteoarthritic lacunae as indicated by their lower degree of anisotropy. The differences in 3D morphology of osteocytes and their lacunae in long bones of different pathologies with different BMD might reflect an adaptation to matrix strain due to different external loading conditions. Moreover, since direct mechanosensing of matrix strain likely occurs by the cell bodies, the differences in osteocyte morphology and their lacunae might indicate differences in osteocyte mechanosensitivity. The exact relationship between osteocyte morphology and bone architecture, however, is complex and deserves further study.

• Low-intensity pulsed ultrasound increases bone volume, osteoid thickness and mineral apposition rate in the area of fracture healing in patients with a delayed union of the osteotomized fibula.

  Authors: Sjoerd Rutten, Peter A Nolte, Clara M Korstjens, Marion A van Duin, Jenneke Klein-Nulend

  Bone. 09/2008; 43(2):348-54.

  INTRODUCTION: Low-intensity pulsed ultrasound (LIPUS) accelerates impaired fracture healing, but the exact mechanism is unknown. The aim of this study was to investigate how LIPUS affects boneINTRODUCTION: Low-intensity pulsed ultrasound (LIPUS) accelerates impaired fracture healing, but the exact mechanism is unknown. The aim of this study was to investigate how LIPUS affects bone healing at the tissue level in patients with a delayed union of the osteotomized fibula, by using histology and histomorphometric analysis to determine bone formation and bone resorption parameters. MATERIALS AND METHODS: Biopsies were obtained from 13 patients (9 female, 4 male; age 42-63) with a delayed union of the osteotomized fibula after a high tibial osteotomy, treated for 2-4 months with or without LIPUS in a randomized prospective double-blind placebo-controlled trial. In the histological sections of the delayed union biopsies, 3 areas of interest were distinguished, i.e. 1) area of new bone formation at the fracture ends, 2) area of cancellous bone, and 3) area of cortical bone. Histomorphometrical analysis was performed to determine bone formation and bone resorption parameters (as well as angiogenesis). RESULTS: In LIPUS-treated delayed unions, endosteal callus formation by direct bone formation without a cartilage intermediate as well as indirect bone formation was observed, while in untreated controls only indirect bone formation was observed. In the area of new bone formation, LIPUS significantly increased osteoid thickness by 47%, mineral apposition rate by 27%, and bone volume by 33%. No increase in the number of blood vessels was seen in the newly formed bony callus. In the area of cancellous bone, bone volume was significantly increased by 17% whereas no effect on osteoid thickness and mineral apposition rate was seen. LIPUS did not affect osteoid volume, osteoid maturation time, number of osteocytes, osteocyte lacunae, or osteoclast-like cells in any of the areas of interest. CONCLUSIONS: Our results suggest that LIPUS accelerates clinical fracture healing of delayed unions of the fibula by increasing osteoid thickness, mineral apposition rate, and bone volume, indicating increased osteoblast activity, at the front of new bony callus formation. Improved stability and/or increased blood flow, but probably not increased angiogenesis, might explain the differences in ossification modes between LIPUS-treated delayed unions and untreated controls.

• Use of low-intensity pulsed ultrasound for posttraumatic nonunions of the tibia: a review of patients treated in the Netherlands.

  Authors: Sjoerd Rutten, Peter A Nolte, Gerard L Guit, Donald E Bouman, Gerardus H R Albers

  The Journal of trauma. 04/2007; 62(4):902-8.

  Low-intensity pulsed ultrasound is effective in fresh fracture healing, resulting in a 40% reduction in healing time. The aim of this study is to determine the effect of ultrasound treatment onLow-intensity pulsed ultrasound is effective in fresh fracture healing, resulting in a 40% reduction in healing time. The aim of this study is to determine the effect of ultrasound treatment on established tibia nonunions. The study group consists of all Dutch patients of posttraumatic consecutive nonunion of the tibia, who started their ultrasound treatment between January 2000 and February 2003. In total, 71 cases have been included, which involve 56 men and 15 women. Mean age was 40 years. Low-intensity pulsed ultrasound was the only new treatment. Strict criteria of enrollment minimized any spontaneous healing chance. According to literature, the spontaneous healing rate was between 5% and 30%. The study outcome, healed or failed, was the primary efficacy parameter. Thirty percent was chosen to represent the maximum expected spontaneous healing and was the basis for statistical evaluation. Stratification was performed for the variables at the ultrasound treatment start. The overall healing rate is 52 of 71 cases (73%). Ultrasound treatment shows a statistical significant higher healing rate compared with that of the spontaneous healing chance (p < 0.0001). Stratification shows no statistical significance for any of the variables analyzed. The long-term follow-up shows high compliance rate and no refractures. Tibia nonunions have a high occurrence rate and cause significant impairment to daily functioning. This study shows that low-intensity pulsed ultrasound is effective in the treatment of established tibia nonunions and can be seen as a good, safe, and cheaper alternative to surgery.