Abstract:

We report the early results of 10 consecutive metal-on-metal resurfacing arthroplasties performed between May 2006 and July 2007 in young, active patients with gross femoral head defects. Failure was classified as revision for any reason. The mean age of our cohort at the time of surgery was 42.8 years and the minimal period of follow-up was 6.9 months. No patients were lost to follow-up. Up to the time of last review, there were no failures and all patients have returned to their preoperative levels of activity. This study shows promising early results of a bone-conserving, hydroxyapatite-coated, uncemented metal-on-metal bearing prosthesis in young, active patients with bony defects of the femoral head.

Authors:

Nemandra A. Sandiford, M.R.C.S., M.F.S.E.M., Clinical Research Fellow, The London Hip Unit, London, United Kingdom, Sarah Muirhead-Allwood, F.R.C.S., Consultant Orthopaedic Surgeon, The London Hip Unit, London, United Kingdom, The Royal National Orthopaedic Hospital, Middlesex, United Kingdom, John Skinner, F.R.C.S. (Tr/Orth), Consultant Orthopaedic Surgeon, The Royal National Orthopaedic Hospital, Middlesex, United Kingdom, Chindu Kabir, M.R.C.S., Clinical Research Fellow, The London Hip Unit, London, United Kingdom

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Abstract:

Over the past decade, the development of modified instrumentation and navigation assistance (permitting in-situ bone excision) have stimulated advances in minimally invasive total hip arthroplasty techniques. These techniques have been developed with an objective to reduce perioperative morbidity, hospitalization expenses, and total rehabilitation time. Furthermore, a concomitant increase in the promotion of these techniques by both industry and orthopaedic surgeons themselves has fueled patient demand. However, the most common minimally invasive techniques used require two incisions and either prevent or limit the surgeon's ability to directly visualize the bony structures of the hip. In this chapter, the authors present a case study that describes a single-incision, soft-tissue sparing, minimally invasive technique for total hip arthroplasty.

Authors:

John T. Williams, Jr., M.D., Chairman, Adult Joint Reconstruction , Department of Orthopedics, Albert Einstein Medical Center, Philadelphia, Pennsylvania, Phillip S. Ragland, M.D., Research Fellow, Department of Orthopedics, Albert Einstein Medical Center, Philadelphia, Pennsylvania

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Abstract:

Conforming articulations potentially decrease polyethylene contact stresses in total knee arthroplasty (TKA); however, less is known about the effect of coronal geometry on tibial loading and clinical failure. This study examined the relationship between coronal plane geometry and loading patterns in the proximal tibia. Composite tibiae were implanted with modular, metal-backed tibial trays and were compressively loaded with conforming and nonconforming ultra-high molecular weight polyethylene (UHMWPE) tibial bearings and comparable femoral components. Changes in strain on the proximal tibia were quantified using a photoelastic strain analysis method. In balanced loading, coronally dished components created a strain increase in the anterior medial tibia while creating a significant strain decrease in the posterior tibia. Proximal tibial strains were decreased and centralized in conforming versus flat articulations. This centralization of loading may lead to a reduction in edge loading during gait. Lower strains were observed with coronally dished implants in key regions corresponding to the clinical overload of the tibia leading to aseptic loosening.

Authors:

Michael E. Berend, M.D., Fellowship Director, Joint Replacement Surgeons of , Indiana Research Foundation, Center for Hip and Knee Surgery, St. Francis Hospital - Mooresville, Mooresville, Indiana, Scott R. Small, M.S., Engineering Director, Joint Replacement Surgeons of , Indiana Research Foundation, Center for Hip and Knee Surgery, St. Francis Hospital - Mooresville, Mooresville, Indiana, Rose-Hulman Institute of Technology, Terre Haute, Indiana, Merrill A. Ritter, M.D., Research Director, Joint Replacement Surgeons of Indiana Research Foundation, Center for Hip and Knee Surgery, St. Francis Hospital - Mooresville, Mooresville, Indiana, Christine A. Buckley, Ph.D., Associate Professor, Rose-Hulman Institute of Technology, Terre Haute, Indiana, James C. Merk, M.S., Rose-Hulman Institute of Technology, Terre Haute, Indiana, W. Kurt Dierking, M.S., Rose-Hulman Institute of Technology, Terre Haute, Indiana

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Abstract:

The purpose of this study was to assess the use of a novel bone void filler consisting of Type I collagen and various growth factors (VEGF, TGFß-1, TGFß-2, IGF-1, BMP-2, BMP-3, and BMP-7) and surgical fixation to treat diaphyseal forearm pseudarthroses. Eleven patients underwent an osteosynthesis procedure for isolated pseudarthrosis fractures of the forearm (six radial and five ulnar diaphysis). The mean duration between the initial failed surgical fixation and re-operation was 38 weeks. Radiographic signs of fracture healing after the application of the bone void filler were noted at a mean of 5 weeks, and complete fracture consolidation was achieved at a mean of 6 weeks. All patients demonstrated improved range of motion and grip strength. Additionally, all patients were pain-free by 6 weeks. The combination of a novel bovine bone-derived bone void filler and stable internal fixation led to union and rapid healing of forearm pseudarthroses.

Authors:

M. Strassmair, M.D., Director, Division of Hand Surgery, Department of Orthopaedic Surgery, Klinikum Starnberg, Starnberg, Germany, M.A. Mont, M.D., Director, Center for Joint Preservation and , Reconstruction, Rubin Institute for Advanced Orthopedics, Sinai Hospital of Baltimore, Baltimore, Maryland, USA, T.M. Seyler, M.D., Fellow, Center for Joint Preservation and , Reconstruction, Rubin Institute for Advanced Orthopedics, Sinai Hospital of Baltimore, Baltimore, Maryland, USA, H. Bosebeck, Ph.D., Chief Scientist & Medical Affairs, Heraeus Medical, Wehrheim, Germany, D.R. Marker, B.S., Medical Student, Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine,, Baltimore, Maryland, USA, D.M. LaPorte, M.D., Assistant Professor, Department of Orthopaedic Surgery, Johns Hopkins University School of Medicine,, Baltimore, Maryland, USA

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Abstract:

Circumferential (360°) fusion yields better long-term outcome in patients with high-grade spondylolisthesis. This result may be achieved by combined anterior and posterior techniques or by an all-posterior approach. As the anterior approach is fraught with numerous complications, many surgeons prefer the all-posterior approach to achieve circumferential fusion. We have described in this chapter the technique of using HMA screws to achieve posterior interbody fusion in situ, to be combined with posterolateral fusion and pedicle screw instrumentation to provide the 360° fusion in high-grade spondylolisthesis. This technique not only provides an increased chance of interbody fusion because of cancellous bone but also avoids the donor site morbidity associated with cortical fibular strut graft.

Authors:

Palaniappan Lakshmanan, M.D., M.S. (Orth), A.F.R.C.S., F.R.C.S. (Orth), Specialist Registrar, Trauma and Orthopedics, Wansbeck General Hospital, Ashington, UK, Sashin Ahuja, M.D., M.S. (Orth.), F.R.C.S., F.R.C.S. (Orth.), Consultant Spinal Surgeon, University Hospital of Wales & Llandough Hospital, Cardiff, UK, Mark Lewis, M.D., F.R.C.S., F.R.C.S. (Orth.), Consultant Orthopedic Surgeon, Royal Gwent Hospital, Newport, UK, John P Howes, M.D., F.R.C.S., F.R.C.S. (Orth.), Consultant Spinal Surgeon, University Hospital of Wales & Llandough Hospital, Cardiff, UK, Paul Rhys Davies, M.D., F.R.C.S., F.R.C.S. (Orth.), Consultant Spinal Surgeon, University Hospital of Wales & Llandough Hospital, Cardiff, UK

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Abstract:

Surgical correction is generally indicated as the primary form of management in children with severe early onset scoliosis. Even so, conservative, nonsurgical treatment is always considered first, as surgical correction carries significant concomitant consequences, including but not limited to crankshaft phenomenon and, more importantly, inhibition of further spine, lung, and chest growth in skeletally immature patients. Fusionless surgical procedures assuage some of these risks, as they are characteristically associated with techniques necessitating spinal fusion. One device looks particularly promising in treating and managing severe early onset scoliosis, the vertical expandable prosthetic titanium rib (VEPTR)-a device that was initially targeted toward children with thoracic insufficiency syndrome (TIS). Despite its promising results in correction of severe early onset scoliosis, as well as associated rib and chest wall deformities, the VEPTR nevertheless has a complication rate comparable to other fusionless techniques. Continued modifications and research will hopefully beget a device that permits thoracic and spinal growth in skeletally immature patients yet with fewer postoperative complications. In this chapter, the authors review the clinical experience with VEPTR to date and present their results in 16 children with congenital scoliosis cared for at Shriners Hospital of Philadelphia.

Authors:

Shailja C. Shah, B.S., Medical Student, Drexel University College of Medicine, Philadelphia, PA, John K. Birknes, M.D., Spine Fellow, Shriners Hospital for Children, Philadelphia, PA, Sukh Sagoo, M.D., Resident, Department of Orthopedics, Shriners Hospital for Children, Philadelphia, PA, Shelby Thome, B.A., Research Associate, Shriners Hospital for Children, Philadelphia, PA, Amer F. Samdani, M.D., Director, Pediatric Spine Service, Shriners Hospital for Children, Philadelphia, PA

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