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The Intrafix device (DePuy Mitek, Raynham, MA) is one of a number of recently developed products whose aim is to improve fixation of quadrupled hamstring grafts when used for anterior cruciate ligament reconstruction. We present a case of failure and intra-articular migration of the sleeve of an Intrafix device causing locking of the knee 10 weeks after anterior cruciate ligament reconstruction. We were unable to identify the cause of the failure or migration of the device. Rehabilitation had been progressing normally and without incident. The broken fragments were removed arthroscopically, and the reconstruction was found to be intact and healing well. Presumably, the device retained enough mechanical function to allow healing to progress, despite failure of the sleeve. This is, to our knowledge, the first reported case of such an event occurring with the new generation of hamstring graft fixation devices.

Background: The implementation of the European Working Time Directive has meant the introduction of shift patterns of working for junior doctors. Patient handover between shifts has become a necessary part of practice in order to reduce the risk of medical errors. Data handed over between shifts are used to prioritise clinical jobs outstanding, and to create theatre lists. We present a closed-loop audit of handover practice to assess whether standardised proformas improve clinical data transfer between shifts during handover in our Orthopaedic Unit., Methods: We collected data handed over between shifts for a period of one week at our department. The data were in the form of hand written data on plain paper used to assist verbal handover. Data were analysed and a standardised handover sheet was trialled. After feedback from juniors the sheet was revised and implemented. A re-audit, of handover data, was then undertaken using the revised standardised proforma during a period of 1 week., Results: Forty-eight patients were handed over in week 1 while 55 patients were handed over during re-audit. The standardised proformas encouraged use of pre-printed patient labels which contained legible patient identifiers, use of labels increased from 72.9% to 93.4%. Handover of outstanding jobs increased from 31.25% to 100%. Overall data handed over increased from 72.6% to 93.2%. Handover of relevant blood results showed little improvement from 18.8% to 20.7%, Conclusion: This audit highlights the issue of data transfer between shifts. Standardised proformas encourage filling of relevant fields and increases the data transferred between shifts thereby reducing the potential for clinical error cause by shift patterns.

The carcinogenic potential of human parathyroid hormone 1-84 (PTH) was assessed by daily subcutaneous injection (0, 10, 50, 150 microg/kg/day) for 2 years in Fischer 344 rats. Histopathological analyses were conducted on the standard set of soft tissues, tissues with macroscopic abnormalities, selected bones, and bones with abnormalities identified radiographically. All PTH doses caused widespread osteosclerosis and significant, dose-dependent increases in femoral and vertebral bone mineral content and density. In the mid-and high-dose groups, proliferative changes in bone increased with dose. Osteosarcoma was the most common change, followed by focal osteoblast hyperplasia, osteoblastoma, osteoma and skeletal fibrosarcoma. The incidence of bone neoplasms was comparable in control and low-dose groups providing a noncarcinogenic dose for PTH of 10 microg/kg/day at a systemic exposure to PTH that is 4.6-fold higher than for a 100 microg dose in humans. The ability of PTH to interact with and balance the effects of both the PTH-1 receptor and the putative C-terminal PTH receptor, may lead to the lower carcinogenic potential observed with PTH than reported previously for teriparatide.

Biomechanical studies involving all-wire and hybrid types of circular frame have shown that oblique tibial fractures remain unstable when they are loaded. We have assessed a range of techniques for enhancing the fixation of these fractures. Eight models were constructed using Sawbones tibiae and standard Sheffield ring fixators, to which six additional fixation techniques were applied sequentially. The major component of displacement was shear along the obliquity of the fracture. This was the most sensitive to any change in the method of fixation. All additional fixation systems were found to reduce shear movement significantly, the most effective being push-pull wires and arched wires with a three-hole bend. Less effective systems included an additional half pin and arched wires with a shallower arc. Angled pins were more effective at reducing shear than transverse pins. The choice of additional fixation should be made after consideration of both the amount of stability required and the practicalities of applying the method to a particular fracture.

Background: Although clear differences in fracture site displacement have previously been demonstrated between transverse and oblique fracture models stabilised by an asymmetrical method, the direction of the obliquity has not been examined biomechanically., Methods: Eight Sawbones tibiae were cut to represent oblique fractures: four ran from antero-inferior to postero-superior and four from antero-superior to postero-inferior. These were fixed with a Sheffield Ring Fixator and cyclically loaded in axial and off-axis compression. Direct measurements were taken of inter-fragmentary displacement., Results: Significant differences were detected between the fracture directions (P < 0.01) and inter-fragmentary displacements were generally reduced in antero-superior to postero-inferior fractures compared with antero-inferio to postero-superior fractures., Interpretation: Fixation asymmetries need to be tailored to specific fracture orientation to improve fracture site mechanics.

Daily sc injections of N-terminal analogs of PTH increase bone mass and decrease fractures in osteoporotic women. We investigated the efficacy and safety of human PTH-(1-84) (full-length PTH) in the treatment of postmenopausal osteoporosis in a double-blind, placebo-controlled study. The women (n = 50-53/group) self-administered PTH (50, 75, or 100 microg) or placebo by daily sc injection for 12 months. PTH treatment induced time- and dose-related increases in lumbar spine bone mineral density (BMD). The 100-microg dose increased BMD significantly at 3 months (+2.0%) and 12 months (+7.8%). BMD underestimated the anabolic effect of PTH in lumbar spine (bone mineral content, +10.0%) because bone area increased significantly (+2.0%). A nonsignificant decrease (-0.9%) in total hip BMD occurred during the first 6 months with the 100-microg dose, but this trend reversed (+1.6%) during the second 6 months. Bone turnover markers increased during the first half of the study and were maintained at elevated levels during the second 6 months. Protocol compliance was excellent (95-98%), and treatment was generally safe and well tolerated. Dose-related incidences of transient hypercalcemia occurred, but only one patient (100-microg group) was withdrawn because of repeated hypercalcemia. Thus, full-length PTH was efficacious and safe over 12 months.

Clinical experience and published studies suggest that oblique fractures of the tibia are associated with delayed healing and non-union. Experimental studies have attributed this to increased shear at the fracture site. We have adopted the practice of using supplementary olive wires to reduce shear when using circular fixation for these fractures. A complete cohort of 54 oblique tibial fractures treated with the Sheffield Ring Fixator (Orthofix, Verona) was reviewed to elucidate the effect of using additional olive wires on fracture healing/treatment times. Fifty patients were studied in the final analysis. With low-energy injuries, the use of olive wires reduced treatment times significantly (no olives: 37 weeks, olives: 22 weeks, P<0.05), although this was not seen with higher energy injuries (no olives: 44 weeks, olives: 39 weeks, P=NS). There was no evidence of additional complications related to their use. We recommend the use of additional olive wires in the circular fixation of these difficult fractures.