Conor Hurson

The role of Dkk1 in bone mass regulation: correlating serum Dkk1 expression with bone mineral density.

The Wnt/β‐catenin pathway is a major signaling cascade in bone biology, playing a key role in regulating bone development and remodeling, with aberrations in signaling resulting in disturbances in bone mass. The objectives of our study were to correlate serum Dkk1 expression with bone mineral density (BMD) and assess the potential role of Dkk1 as a serological marker of bone mass. Serum was collected from a cohort of patients (n = 36), 18 patients with a reduced BMD and 18 control patients. Serum Dkk1 expression as quantified by ELISA was correlated with lumbar and femoral t‐ and z‐scores. Serum Dkk1 concentration in the osteoporosis group was significantly higher than control group (941 ± 116 vs. 558 ± 47 pg/ml, p < 0.01). Serum Dkk1 expression was highly correlated with bone mass variables with inverse associations found between serum Dkk1 expression and lumbar t‐score (r = −0.34, p = 0.00433), lumbar z‐score (r = −0.22, p = 0.1907), femur t‐score (r = −0.42, p = 0.0101), and femur z‐score (r = −0.43, p = 0.0089). Our data further emphasizes the pivotal role played by Wnt/β‐catenin signaling in bone mass regulation. Dkk1, a powerful antagonist of canonical Wnt signaling, may have a role to play as a serological marker for disorders of bone mass, warranting further evaluation.

Pediatric trampoline injuries

Introduction: The recreational use of trampolines has increased dramatically during the last 10 years. There has been a striking increase in the number of children presenting to fracture clinics with injuries associated with trampoline use. This increase in trampoline injuries has been reported in North America, but there has been a paucity of research in this area in Europe. Methods: We prospectively recorded details of patients presenting to our institution, Our Ladys Childrens Hospital, Crumlin (Dublin, Ireland), during the busy summer months of June, July, and August 2005. Details recorded included type and mechanism of injury, the mode of referral, treatment, inpatient days, outpatient visits, specific details relating to trampoline safety, and an analysis of the cost of medical care. Results: There were 101 patients treated for trampoline-related injuries in 3 months from June to August 2005. This represented 1.5% of the total attendances to the emergency department. The average age was 8.5 years (range, 1.4-17.4 years). There were 55 fractures, 38 soft tissue injuries, 5 head injuries, and 5 neck injuries, with an average Pediatric Trauma Score of 11.4. Fifty seven percent (58/101) of patients were on the trampoline with at least 1 other person. Twenty patients (19.8%) were admitted to hospital requiring 71 inpatient days. Twelve patients were treated in theatre. There were 163 fracture clinic visits, 212 x-rays, and 2 magnetic resonance imaging scans. Conclusions: Trampolines are a high-risk activity with the potential for significant orthopaedic injury. In Ireland, we have recently seen a dramatic increase in pediatric trampoline-related injuries mirroring the trend in the United States during the last 10 to 15 years. We found that more than 1 individual on a trampoline is a major risk factor for injury, where the lightest person is 14 times more likely to be injured than the heavier. The lighter person also has a greater chance of being injured with smaller numbers on the trampoline. We reiterate the American Academy of Pediatrics policy statement advice that trampolines be used only in supervised training programs-never at home, in outdoor playgrounds, or in schools. The public should be made aware of the potential dangers of trampolines through public health campaigns, radio, and television.

Incomplete Atypical Femoral Fractures: Assessing the Diagnostic Utility of DXA by Extending Femur Length

Atypical femoral fractures (AFFs) are associated with prolonged bisphosphonate therapy. A feature of incomplete AFF is a localized periosteal reaction. It has been suggested that extending the length of the femur image at the time of dual-energy X-ray absorptiometry (DXA) may diagnose an incomplete AFF. In patients older than 50 yr on bisphosphonate therapy for more than 5 yr, we extended femur length at the time of routine DXA. Abnormal DXA images were suggested in 19 of 257 patients (7.4%). On X-ray, 7 patients (2.7%) showed no abnormality, 7 patients (2.7%) showed evidence of AFF, and 5 patients (2.0%) showed an unrelated radiographic abnormality. Of the 7 cases with X-ray evidence of AFF, 5 had a periosteal flare and 2 had a visible fracture line, both of whom needed insertion of an intramedullary nail. We demonstrated that it is feasible to detect incomplete AFF early using extended femur length imaging with a prevalence in our sample of 2.7% (95% confidence interval: 1.7%-3.7%).

Clinician approach to diagnosis of stress fractures including bisphosphonate-associated fractures

Stress fractures are repetitive strain injuries that occur in normal bones and in abnormal bones. Stress fractures share many features in common but differences depend on the status of the underlying bone. This review article for clinicians addresses aspects about stress fractures with particular respect to fatigue fractures, Looser zones of osteomalacia, atypical Looser zones, atypical femoral fractures associated with bisphosphonate therapy and stress fractures in Pagets disease of bone.

Improving Hip Fracture Care in Ireland: A Preliminary Report of the Irish Hip Fracture Database

Introduction. Hip fractures are common injuries in the older persons, with significant associated morbidity and mortality. The Irish Hip Fracture Database (IHFD) was implemented to monitor standards of care against international standards. Methods. The IHFD is a clinically led web-based audit. We summarize the data collected on hip fractures from April 2012 to March 2013 from 8 centres. Results. There were 843 patients with the majority being (70%) female. The 80–89-year age group accounted for the majority of fractures (44%). Most (71%) sustained a fall at home. Intertrochanteric fractures (40%) were most common. Only 28% were admitted to an orthopaedic ward within 4 hours. The majority (97%) underwent surgery with 44% having surgery within 36 hours. Medical optimization (35%) and lack of theatre space (26%) accounted for most of the surgical delay. While 29% were discharged home, 33% were discharged to a nursing home or other long-stay facilities. There was a 4% in-hospital mortality rate. Conclusions. Several key areas in both the database and aspects of patient care needing improvement have been highlighted. The implementation of similar databases has led to improved hip fracture care in other countries and we believe this can be replicated in Ireland.

Abdominal aortic aneurysm repair and colonic infarction: a risk factor appraisal.

Objective  Colonic infarction is a recognized complication of abdominal aortic aneurysm (AAA) surgery. The clinical difficulty in establishing the diagnosis combined with the patients poor physiological status is usually associated with a fatal outcome. We assessed our experience with this problem to identify a possible risk factor profile for these patients.

LUNG TISSUE STORAGE: OPTIMIZING CONDITIONS FOR FUTURE USE IN MOLECULAR RESEARCH

The quality of tissue studied impacts greatly on oligonucleotide microarray results, emphasizing the importance of harvesting techniques. The analyzed RNA extracted from human lung samples preserved via 4 different storage conditions (RNAlater, phosphate-buffered saline, TRIzol, liquid nitrogen). RNA was assessed by denaturing gel electrophoresis, Agilent bioanalysis, real-time polymerase chain reaction (PCR), and Test3 Affymetrix chip hybridization. Results revealed better quality RNA from RNAlater samples on gel electrophoresis and bioanalysis. RNAlater samples also showed greater yield (r18s via PCR P <.05) and resulted in better Test3 chips hybridization (p <.05), suggesting RNAlater was superior at preserving lung tissue nucleic acid.

Biomechanical analysis of tibial tray fractures post total knee arthroplasty

The fracture of the tibial tray is a rare complication post total knee arthroplasty. We present the case of a 74-year-old lady who had pain in the left knee due to an anteromedial fracture of her metal tibial tray post total knee arthroplasty with a kinematic (Howmedica) prosthesis. There are 25 reported cases of fractures of the posterior-medial aspect of the tibial tray. This is the first case describing an anteromedial tibial tray fracture. We performed a retrieval analysis of the polyethylene component and the fractured tibial base plate and reviewed the literature to determine the predisposing factors contributing to tibial tray fractures. Tibial component malalignment, excessive polyethylene wear and subsequent bone lysis, inherent metallurgical weakness and certain design features of the tray have been identified as the possible contributing factors to failure in this case.RésuméLa fracture du plateau tibial est une complication rare après arthroplastie du genou. Les auteurs rapportent un cas de fracture de la partie antéromédiale du plateau tibial d’une prothèse Kinematic (Howmedica) chez une femme de 74 ans. Alors que 25 cas de fractures de la partie postéromédiale ont été publiés, ce cas est le premier concernant la portion antéromédiale du plateau tibial. Parmi les facteurs prédisposants, la malposition du composant tibial, l’usure excessive du polyéthylène, l’ostéolyse secondaire à l’usure, des défauts métallurgiques et certaines caractéristiques du dessin du plateau peuvent être incriminés.

Thoracoscopic management of primary spontaneous pneumothorax.

BackgroundVideo-assisted thoracoscopic surgery (VATS) is the preferred option for the surgical management of primary spontaneous pneumothorax (PSP).AimsTo evaluate the role of thoracoscopic blebectomy with and without chemical pleurodesis.MethodsA retrospective study was performed on 113 consecutive cases carried out in one unit.ResultsOne hundred and thirteen VATS procedures were performed on 108 patients. The mean age was 23 years (range 14–45). The male to female ratio was 82:26. Recurrent pneumothorax was the indication for surgery in 80%. Conversion to an open procedure was required in 10 cases (9%), most commonly due to severe adhesions. Successful endoscopic blebectomy was performed in 98 cases (87%), 48 of which had an additional chemical pleurodesis. Follow-up is currently to a mean of 28 months. Recurrence has occurred in eight cases, including only three in the group managed with additional chemical pleurodesis (6.25%).ConclusionVATS with blebectomy and chemical pleurodesis is a safe and effective procedure in the management of PSP.

Tourniquet-associated povidone-iodine-induced chemical burns.

A 75-year-old man underwent routine left total knee arthroplasty under a spinal anaesthetic. An adequately sized pneumatic tourniquet with wool padding was used and a clear adhesive drape applied circumferentially around the thigh to isolate the tourniquet. A 10% w/w povidone-iodine solution had been used to prepare the left leg. The tourniquet was inflated just prior to cementation of the implants with a tourniquet time of 40 min. The total …