Periprosthetic fracture (PF) after primary total hip arthroplasty
(THA) is an uncommon but potentially devastating complication. This
study aims to investigate the influence of cemented stem designs
on the risk of needing a revision for a PF. We analysed data on 257 202 primary THAs with cemented stems
and 390 linked first revisions for PF recorded in the National Joint
Registry (NJR) of England, Wales and Northern Ireland to determine
if a cemented femoral stem brand was associated with the risk of
having revision for a PF after primary THA. All cemented femoral
stem brands with more than 10 000 primary operations recorded in
the NJR were identified. The four most commonly used cemented femoral
stems were the Exeter V40 (n = 146 409), CPT (n = 24 300), C-Stem
(n = 15 113) and Charnley (n = 20 182). We compared the revision risk ratios due to PF amongst the stems
using a Poisson regression model adjusting for patient factors.
Compared with the Exeter V40, the age, gender and ASA grade adjusted
revision rate ratio was 3.89 for the cemented CPT stem (95% confidence
interval (CI) 3.07 to 4.93), 0.89 for the C-Stem (95% CI 0.57 to
1.41) and 0.41 for the Charnley stem (95% CI 0.24 to 0.70).Aims
Patients and Methods
The use of journal clubs and, more recently,
case-based discussions in order to stimulate debate among orthopaedic
surgeons lies at the heart of orthopaedic training and education. A
virtual learning environment can be used as a platform to host virtual
journal clubs and case-based discussions. This has many advantages
in the current climate of constrained time and diminishing trainee
and consultant participation in such activities. The virtual environment
model opens up participation and improves access to journal clubs
and case-based discussions, provides reusable educational content,
establishes an electronic record of participation for individuals,
makes use of multimedia material (including clinical imaging and
photographs) for discussion, and finally, allows participants to
link case-based discussions with relevant papers in the journal
club. The Leicester experience highlights the many advantages and some
of the potential difficulties in setting up such a virtual system
and provides useful guidance for those considering such a system
in their own training programme. As a result of the virtual learning
environment, trainee participation has increased and there is a
trend for increased consultant input in the virtual journal club
and case-based discussions. It is likely that the use of virtual environments will expand
to encompass newer technological approaches to personal learning
and professional development.
Digital radiography is becoming widespread. Accurate pre-operative templating of digital images of the hip traditionally involves positioning a calibration object at its centre. This can be difficult and cause embarrassment. We have devised a method whereby a planar disc placed on the radiographic cassette accounts for the expected magnification. Initial examination of 50 pelvic CT scans showed a mean hip centre distance of 117 mm (79 to 142) above the gluteal skin. Further calculations predicted that a disc of 37.17 mm diameter, placed on the cassette, would appear identical to a 30 mm sphere placed at the level of the centre of the hip as requested by our templating software. We assessed accuracy and reproducibility by ‘reverse calibration’ of 20 radiographs taken three months after hip replacement using simultaneous sphere and disc methods, and a further 20 with a precision disc of accurate size. Even when variations in patient size were ignored, the disc proved more accurate and reliable than the sphere. The technique is reliable, robust, cost effective and acceptable to patients and radiographers. It can easily be used in any radiography department after a few simple calculations and manufacture of appropriately-sized discs.
A case of pencil-gore granuloma occurring 45 years after the initial injury is described. The clinical and radiological presentation was suggestive of a soft-tissue sarcoma. The diagnosis was confirmed by biopsy, which also revealed foreign body fragments which, on spectometric analysis, had high concentrations of carbon and aluminium.
Ten patients underwent endoprosthetic replacement of the distal humerus for bone tumours over a period of 30 years. There were eight primary and two secondary tumours in four men and six women with a mean age of 47.5 years (15 to 76). The mean follow-up was eight years (9 months to 31 years). Four patients required further surgery, three having revision for aseptic loosening; two of these and one other later needing a rebushing. There were no cases of postoperative nerve palsy, infection, local recurrence or mechanical failure of the implant. Four patients died from their disease, all with the prosthesis functioning satisfactorily. At follow-up the mean flexion deformity of the elbow was 15° (0 to 35) and the mean range of flexion was 115° (110 to 135). The functional results showed a mean Toronto extremity salvage score of 73% of normal. Endoprosthetic replacement of the distal humerus and elbow is a satisfactory method of treating these rare tumours.
