Other articles by Caroline A. Hundepool on PubMed

• Early Posttraumatic Psychological Stress Following Peripheral Nerve Injury: a Prospective Study Journal of Plastic, Reconstructive & Aesthetic Surgery : JPRAS. Oct, 2013  |   Pubmed ID: 23759202 Psychological symptoms frequently accompany severe injuries of the upper extremities and are described to influence functional outcome. As yet, little knowledge is available about the occurrence of posttraumatic psychological stress and the predictive characteristics of peripheral nerve injuries of the upper extremity for such psychological symptoms. In this prospective study, the incidence of different aspects of early posttraumatic stress in patients with peripheral nerve injury of the forearm is studied as well as the risk factors for the occurrence of early psychological stress.
• The Effect of Stem Cells in Bridging Peripheral Nerve Defects: a Meta-analysis Journal of Neurosurgery. Jul, 2014  |   Pubmed ID: 24816327 OBJECT.: For decades the gold standard for reconstructing a large peripheral nerve defect has been, and remains, the nerve autograft. Alternatives to the nerve autograft include biological conduits and vessels. Adding stem cells in the lumen of a nerve conduit has been the subject of multiple studies. The purpose of the present meta-analysis was to summarize animal experimental studies on the effect of stem cells as a luminal additive when reconstructing a peripheral nerve defect with a nerve graft.
• Prognostic Factors for Outcome After Median, Ulnar, and Combined Median-ulnar Nerve Injuries: a Prospective Study Journal of Plastic, Reconstructive & Aesthetic Surgery : JPRAS. Jan, 2015  |   Pubmed ID: 25448370 A major problem in the surgical treatment of peripheral nerve injuries of the upper extremities is the unpredictable final outcome. More insight and understanding of the prognostic factors is necessary to improve functional outcome after repair of the peripheral nerves. The objective of this study was to identify prognostic factors for the functional recovery of peripheral nerve injury of the forearm and their independent contribution in the outcome in the first year after reconstruction.
• Ultrasonographic Quantification of Intrinsic Hand Muscle Cross-sectional Area; Reliability and Validity for Predicting Muscle Strength Archives of Physical Medicine and Rehabilitation. May, 2015  |   Pubmed ID: 25482051 To investigate whether ultrasonographic measurement of the cross-sectional area (CSA) of the intrinsic hand muscles can be used to predict muscle strength in a valid and reliable manner, and to determine if this method can be used for follow-up of patients with peripheral nerve injury between the wrist and elbow.
• Noninvasive Ultrasound of the Tibial Muscle for Longitudinal Analysis of Nerve Regeneration in Rats Plastic and Reconstructive Surgery. Nov, 2015  |   Pubmed ID: 26505720 Today's criterion standards for measuring functional recovery after nerve trauma in experimental studies are the muscle mass ratio and the isometric tetanic force; both tests are invasive and require a sacrificial procedure. The authors propose ultrasound as a noninvasive method to determine muscle atrophy, and evaluate its validity and reliability by comparing it to muscle mass ratio, isometric tetanic force, and histology.
• Motor Nerve Recovery in a Rabbit Model: Description and Validation of a Noninvasive Ultrasound Technique The Journal of Hand Surgery. Jan, 2016  |   Pubmed ID: 26710731 To develop and validate a noninvasive ultrasound technique for the longitudinal analysis of functional recovery after segmental peroneal nerve reconstruction in a rabbit model.
• The Learning Rate in Three Dimensional High Definition Video Assisted Microvascular Anastomosis in a Rat Model Journal of Plastic, Reconstructive & Aesthetic Surgery : JPRAS. Nov, 2016  |   Pubmed ID: 27650118 Three-dimensional (3D) high definition (HD) video systems are changing microsurgical practice by providing stereoscopic imaging not only for the surgeon and first assistant using the binocular microscope, but also for others involved in the surgery. The purpose of this study was to evaluate the potential to replace the binocular microscope for microarterial anastomoses and assess the rate of learning based on surgeons' experience. Two experienced and two novice microsurgeons performed a total of 88 rat femoral arterial anastomoses: 44 using a 3D HD video device ('Trenion', Carl Zeiss Meditech) and 44, a binocular microscope. We evaluated anastomosis time and modified OSATS scores as well as the subjects' preference for comfort, image adequacy and technical ease. Experienced microsurgeons showed a steep learning curve for anastomosis times with equivalent OSATS scores for both systems. However, prolonged anastomosis times were required when using the novel 3D-HD system rather than direct binocular vision. Comparable learning rates for anastomosis time were demonstrated for novice microsurgeons and modified OSATS scores did not differ between the different viewing technologies. All microsurgeons reported improved comfort for the 3D HD video system but found the image quality of the conventional microscope superior, facilitating technical ease. The present study demonstrates the potential of 3D HD video systems to replace current binocular microscopes, offering qualitatively-equivalent microvascular anastomosis with improved comfort for experienced microsurgeons. However, image quality was rated inferior with the 3D HD system resulting in prolonged anastomosis times. Microsurgical skill acquisition in novice microsurgeons was not influenced by the viewing system used.
• Recipient-derived Angiogenesis with Short Term Immunosuppression Increases Bone Remodeling in Bone Vascularized Composite Allotransplantation: A Pilot Study in a Swine Tibial Defect Model Journal of Orthopaedic Research : Official Publication of the Orthopaedic Research Society. Jun, 2017  |   Pubmed ID: 27471833 Current vascularized composite allotransplantation (VCA) transplantation protocols rely upon life-long immune modulation to maintain tissue perfusion. Alternatively, bone-only VCA viability may be maintained in small animal models using surgical angiogenesis from implanted autogenous vessels to develop a neoangiogenic bone circulation that will not be rejected. This study tests the method's efficacy in a large animal model as a bridge to clinical practice, quantifying the remodeling and mechanical properties of porcine tibial VCAs. A segmental tibial defect was reconstructed in Yucatan miniature swine by transplantation of a matched tibia segment from an immunologically mismatched donor. Microsurgical repair of nutrient vessels was performed in all pigs, with simultaneous intramedullary placement of an autogenous arteriovenous (AV) bundle in Group 2. Group 1 served as a no-angiogenesis control. All received 2 weeks of immunosuppression. After 16 weeks, micro-CT and histomorphometric analyses were used to evaluate healing and remodeling. Axial compression and nanoindentation studies evaluated bone mechanical properties. Micro-CT analysis demonstrated significantly more new bone formation and bone remodeling at the distal allotransplant/recipient junction and on the endosteal surfaces of Group 2 tibias (p = 0.03). Elastic modulus and hardness were not adversely affected by angiogenesis. The combination of 2 weeks of immunosuppression and autogenous AV-bundle implantation within a microsurgically transplanted tibial allotransplant permitted long-term allotransplant survival over the study period of 16 weeks in this large animal model. Angiogenesis increased bone formation and remodeling without adverse mechanical effects. The method may allow future composite-tissue allotransplantation of bone without the risks associated with long-term immunosuppression. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1242-1249, 2017.
• Safety and Suitability of Finger Replantations As a Residency Training Procedure: A Retrospective Cohort Study With Analysis of the Initial Postoperative Outcomes Annals of Plastic Surgery. Apr, 2017  |   Pubmed ID: 27893542 Finger replantations demand technical excellence in microsurgery and hand trauma care. The objective of this study was to determine whether finger replantations constitute an appropriate and safe procedure for residency training. Additionally, the prognostic risk factors for the need to take a replanted finger back to the operation room and replant failure were analyzed.All patients who underwent finger replantation after complete amputation between 2007 and 2015 were included in a retrospective comparative study. These patients were either treated by an attending plastic surgeon (cohort 1) or by a postgraduate year 5 or 6 resident under supervision (cohort 2). Logistic regression analysis was used to identify the prognostic risk factors for emergent take backs and replant failures.A total of 109 completely amputated fingers were replanted in 89 patients. Fifty-seven digits were replanted in cohort 1, and 52 digits were replanted in cohort 2. Patient demographic data revealed an equal distribution between the two cohorts with an overall finger-replantation success rate of 67.0%. The prognostic risk factors related to increased take back and replant failure rates were fewer than two venous anastomoses (take back odds ratio [AOR], 0.27; confidence interval (CI), 0.12-0.63; and replant failure AOR, 0.21; 95% CI, 0.08-0.55) and intraoperative noticeable problems regarding the vascular anastomoses (take back AOR, 2.26; 95% CI, 0.96-5.33 and replant failure AOR, 2.45; 95% CI, 1.00-6.00). The type of surgeon did not exhibit an influence on the risk of take back (OR, 1.14; 95% CI, 0.53-2.41) or replant failure (OR, 1.03; 95% CI, 0.46-2.30). Similarly, after adjusting for all risk factors, the risks for take backs (AOR, 1.04; 95% CI, 0.46-2.36) and replant failures (AOR, 0.91; 95% CI, 0.38-2.19) did not differ between the 2 cohorts.Finger replantations can be applied as a safe procedure in residency training under standardized conditions and do not negatively affect quality of care. Technical proficiency in microsurgery and elective and trauma hand care as well as supervision by an experienced plastic or hand surgeon are mandatory. Regardless of the surgeons' experience, fewer than 2 venous anastomoses and the presence of intraoperative vascular anomalies represent significant prognostic risk factors for postoperative complications.
• Optimizing Decellularization Techniques to Create a New Nerve Allograft: an in Vitro Study Using Rodent Nerve Segments Neurosurgical Focus. Mar, 2017  |   Pubmed ID: 28245670 OBJECTIVE Commercially available processed nerve allografts have been shown to be inferior to autografts in previous animal studies. The authors hypothesized that combining different processing and storage techniques will result in improved nerve ultrastructure preservation, lower immunogenicity, and minimized cellular debris. Different processing protocols were evaluated using chemical detergents, enzymes, and irradiation, with the addition the of enzyme elastase, were used. Additionally, the difference between cold and frozen storage was investigated. The goal of this study was to create an optimized nerve allograft. METHODS Fifty rat nerves were decellularized with modifications of previous protocols and the addition of elastase. Subsequently, the nerve segments were stored at either 4°C or -80°C. Both processed and fresh control nerves were analyzed with confocal microscopy using immunohistochemical staining on the basal lamina (laminin γ-1), Schwann cells (S100 protein), and immunogenicity using major histocompatibility complex-I (MHCI) staining. Morphology of the ultrastructure and amount of cellular debris were analyzed on cross-sections of the nerves stained with toluidine blue and H & E, and by using electron microscopy. RESULTS Nerve ultrastructure was preserved with all decellularization protocols. Storage at -80°C severely altered nerve ultrastructure after any decellularization method. Elastase was found to significantly reduce the immunogenicity and amount of Schwann cells, while maintaining good structural properties. CONCLUSIONS Reduced immunogenicity, diminished cellular debris, and the elimination of Schwann cells was observed when elastase was added to the nerve processing while maintaining ultrastructure. Storage at -80°C after the decellularization process heavily damaged the nerve ultrastructure as compared with cold storage. Further in vivo studies are needed to prove the nerve regenerative capacity of these optimized allografts.
• The Effect of Full Dose Composite Tissue Allotransplantation Immunosuppression on Allograft Motor Nerve Regeneration in a Rat Sciatic Nerve Model Microsurgery. Aug, 2017  |   Pubmed ID: 28792625 The purpose of this study was to identify which triple immunosuppressive protocols, currently used for vascularized composite allotransplantation in the clinic, will have the best effect on motor function recovery following nerve allograft reconstruction.