Assessment of Head Displacement and Disassembly Force With Increasing Assembly Load at the Head/Trunnion Junction of a Total Hip Arthroplasty Prosthesis.

BACKGROUND: Most femoral components used now for total hip arthroplasty are modular, requiring a strong connection at assembly. The aim of this study was to assess the effect of assembly force on the strength of head-trunnion interface and to measure the initial displacement of the head on the trunnion with different assembly forces. METHODS: Three assembly load levels were assessed (A: 2 kN, B: 4 kN, C: 6 kN) with 4 implants in each group. The stems were mounted in a custom rig and the respective assembly loads were applied to the head at a constant rate of 0.05 kN/s (ISO7260-10:2003). Load levels were recorded during assembly. Head displacement was measured with a laser sensor. The disassembly force was determined by a standard pull-off test. RESULTS: The maximum head displacement on the trunnion was significantly different between the 2 kN group and the other 2 groups (4 kN, 6 kN, P = .029), but not between the 4 kN and 6 kN groups (P = .89). The disassembly forces between the 3 groups were significantly different (mean ± standard deviation, A: 1316 ± 223 kN; B: 2224 ± 151 kN; C: 3965 ± 344 kN; P = .007), with increasing assembly load leading to a higher pull-off force. For the 4 kN and 6 kN groups, a first peak of approximately 2.5 kN was observed on the load recordings during assembly before the required assembly load was eventually reached corresponding to sudden increase in head displacement to approximately 150 µm. CONCLUSION: An assembly force of 2 kN may be too low to overcome the frictional forces needed to engage the head and achieve maximum displacement on the trunnion and thus an assembly load of greater than 2.5 kN is recommended.

The missing piece of the trauma armoury-medial femoral condyle plate.

Fixation of distal femoral fractures is often challenging due to the fracture configuration and associated poor bone quality. Dual plating (lateral and medial) has become an acceptable option to provide improved stability versus a single plate fixation. Though there are several commercially available anatomically designed plates for the lateral femoral condyle, there is no anatomic plate available in UK specifically for medial fixation of distal femur fractures. Our aim is to determine the best suited pre-contoured plate for stabilising the medial femoral condyle (MFC). Right sided femur sawbones were used to determine how well 18 different pre-contoured anatomical plates (Depuy Synthes, Leeds, UK) fit the medial femoral condyle. Some of these had variable angle (VA) option. Lift off, fit and notch penetration were assessed and recorded independently by 4 orthopaedic trauma surgeons. The number and distribution of screws in the MFC that each plate allowed was also determined. To do this the MFC was divided into quadrants: Proximal anterior (PA), distal anterior (DA), proximal posterior (PP) and distal posterior (DP). The ipsilateral anterolateral proximal tibial (VA and 4.5 mm non-VA), PHILOS, posteromedial proximal tibial and ipsilateral lateral extra-articular distal humeral plate offered good sagittal fit, less than 2 mm lift off at the condyles and no diaphyseal lift off. Plate positioning in the PA quadrant offered the best fit. The ipsilateral anterolateral proximal tibial plates (VA) and PHILOS allowed at least 4 screws to be placed in the PA and 2 in the PP quadrant with no notch penetration. The Tomofix provided good fit, but all 4 screws were in PA quadrant, with distal screws causing notch penetration. The non-VA and PHILOS plates did not offer the VA advantage. The ipsilateral anterolateral proximal tibial VA plates provided the best anatomical fit for the MFC with the greatest number of screws in the condylar quadrants with the option of variable angle screw placement.

Improving communication with primary care to ensure patient safety post-hospital discharge.

INTRODUCTION: Successful communication between hospitals and primary care is of paramount importance to enable continuity of care and maintain patient safety post-discharge. Discharge summaries are the simplest way for GPs to obtain information about a patient's hospital stay. A quality improvement study was conducted with the aim of increasing the content of discharge summaries for inpatients in the authors' department. METHODS: A prospective review of 60 electronic discharge summaries was conducted over a 6-week period. The content of discharge summaries was reviewed in accordance with local trust guidelines. Targeted, intensive, cost and time-effective educational interventions were then conducted. A post-intervention review of 60 discharge summaries was performed. A further review of 60 discharge summaries was performed after 12 months. RESULTS: Initial results pre-intervention confirmed suboptimal content of discharge summaries. Post-intervention results showed each component of discharge summaries improved in terms of content, with six of eight components having a statistically significant (P<0.05) increase. This was maintained after 12 months. CONCLUSIONS: This study has demonstrated how simple, intensive educational sessions can lead to an improvement in discharge summaries and communication with primary care.

Quality of Plaster Molding for Distal Radius Fractures Is Improved Through Focused Tuition of Junior Surgeons.

OBJECTIVES: Successful nonoperative management of distal radius fractures requires an adequately reduced fracture held in a well-molded cast. The purpose of this study was to determine whether a targeted teaching session to the same group of junior doctors led to objective improvement in fracture reduction and plaster molding and hence a decrease in the redisplacement of these fractures. DESIGN: Retrospective review. SETTING: Level I academic trauma center. METHODS: A retrospective review of all dorsally angulated distal radius fractures treated in plaster that presented to our plaster room over a 4-week period (group 1, n = 52). This was followed by the intervention and a subsequent 4-week prospective review (group 2, n = 36). Radiographs were reviewed before manipulation, after manipulation, and at follow-up by a single senior orthopaedic trainee using predetermined criteria. INTERVENTION: A targeted teaching session on fracture reduction and cast molding to the same group of junior doctors involved in managing all these cases. MAIN OUTCOME MEASURES: Adequate fracture reduction, plaster molding, redisplacement, and further intervention before and after the targeted intervention. RESULTS: In group 1, 85% had adequate fracture reduction but only 36% showed adequate molding. This was improved in group 2%-94% adequate reduction and 65% adequate molding (P = 0.022). The rate of redisplacement was improved from 65% to 44% in group 2. In both groups, the rate of redisplacement was around 20% for adequately reduced and molded fractures, compared with around 90% for adequately reduced but inadequately molded cases (P < 0.001). The rate of further intervention improved from 27% to 8% (P = 0.052). CONCLUSIONS: We recommend that specific teaching focusing on fracture reduction and molding techniques is included in orthopaedic juniors' induction teaching or as a separate session. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Data protection among junior medical staff: a questionnaire study.

OBJECTIVE: There have been numerous reports of loss of confidential information amongst UK public agencies. The aim of the study was to examine current standards of practice and knowledge of junior medical staff with respect to management of patient identifiable information. METHODS: An anonymous multiple choice questionnaire was completed by 50 junior medical staff in each of 2 separate district general hospitals in the UK. RESULTS: Sixty-two percent of physicians surveyed held patient identifiable information electronically, outside of normal NHS use. Thirty percent of physicians used portable memory sticks, of which, 68% were not password protected. Ninety percent of physicians used patient ward lists in paper format with 18% frequently using a domestic waste bin for disposal. Thirty-five percent of physicians were aware of the Caldicott principles, and 58% were aware of the Data Protection Act as applied to their duties. CONCLUSIONS: Despite having statutory duties toward the management of patient identifiable information, many physicians are not aware of their responsibilities and obligations. This is unlikely to be an isolated local issue. More emphasis needs to be placed on data management in hospital induction procedures for new employees, and security measures, such as encryption software, should be made more widely available.

An isolated articular surface fracture of the distal patella: an unusual and previously unreported paediatric injury.

Paediatric patella fractures are uncommon, accounting for less than 1% of all paediatric fractures. This case report describes a previously undocumented patella fracture in a child, with a clear mechanism of injury. We present a case of a previously healthy 14-year-old boy who fell directly onto his right knee after coming off his pushbike. He sustained an isolated fracture involving the articular surface of the distal part of the patella with minimal displacement. The patient was managed conservatively in a Richard splint for three weeks, followed by a knee brace with gradually increasing degrees of flexion. He was instructed to be nonweight bearing for two weeks and then partial weight bearing for six weeks. At the final followup, after 9 weeks, the patient had full return of function and standard radiographs show the fracture to be healed. This case report has demonstrated how direct compression to the paediatric patella can cause a fracture isolated to its articular surface. It has detailed the natural progression of this injury to radiographic union, using a conservative management strategy. The authors believe that this case report provides an interesting insight into the variation of paediatric patella fractures and their contrasting management strategies.

Osteoma cutis masquerading as an ingrowing toenail: a case report.

Osteoma cutis of the foot is extremely rare and there are very few reported cases. The incidence of in-growing toenail in the United Kingdom is estimated to be 10,000 new cases per year and many are treated non-operatively. We present a case where osteoma cutis was masquerading as an in-growing toenail, and wish to highlight the condition as a differential diagnosis for this condition. There have been case reports of bony cutaneous lesions of the foot, both benign and malignant and so these are especially important to consider in the differential diagnoses where non-operative management is being considered.