We studied the safety of external
Aims. Anatomical atlases document classical safe corridors for the
placement of transosseous fine wires through the calcaneum during
circular frame external
Objectives. Taper junctions between modular hip arthroplasty femoral heads and stems fail by wear or corrosion which can be caused by relative motion at their interface. Increasing the assembly force can reduce relative motion and corrosion but may also damage surrounding tissues. The purpose of this study was to determine the effects of increasing the impaction energy and the stiffness of the impactor tool on the stability of the taper junction and on the forces transmitted through the patient’s surrounding tissues. Methods. A commercially available impaction tool was modified to assemble components in the laboratory using impactor tips with varying stiffness at different applied energy levels. Springs were mounted below the modular components to represent the patient. The pull-off force of the head from the stem was measured to assess stability, and the displacement of the springs was measured to assess the force transmitted to the patient’s tissues. Results. The pull-off force of the head increased as the stiffness of the impactor tip increased but without increasing the force transmitted through the springs (patient). Increasing the impaction energy increased the pull-off force but also increased the force transmitted through the springs. Conclusions. To limit wear and corrosion, manufacturers should maximize the stiffness of the impactor tool but without damaging the surface of the head. This strategy will maximize the stability of the head on the stem for a given applied energy, without influencing the force transmitted through the patient’s tissues. Current impactor designs already appear to approach this limit. Increasing the applied energy (which is dependent on the mass of the hammer and square of the contact speed) increases the stability of the modular connection but proportionally increases the force transmitted through the patient’s tissues, as well as to the surface of the head, and should be restricted to safe levels. Cite this article: A. Krull, M. M. Morlock, N. E. Bishop. Maximizing the
Failed internal
The purpose of this study was to determine whether
it would be feasible to use oblique lumbar interbody
Objectives. Secondary fracture healing is strongly influenced by the stiffness of the bone-fixator system. Biomechanical tests are extensively used to investigate stiffness and strength of
With the development of systems of trauma care the management of pelvic disruption has evolved and has become increasingly refined. The goal is to achieve an anatomical reduction and stable
Aims. The aim of this study was to report the mid-term clinical outcome
of cemented unlinked J-alumina ceramic elbow (JACE) arthroplasties
when used in patients with rheumatoid arthritis (RA). Patients and Methods. We retrospectively reviewed 87 elbows, in 75 patients with RA,
which was replaced using a cemented JACE total elbow arthroplasty
(TEA) between August 2003 and December 2012, with a follow-up of
96%. There were 72 women and three men, with a mean age of 62 years
(35 to 79). The mean follow-up was nine years (2 to 14). The clinical condition
of each elbow before and after surgery was assessed using the Mayo
Elbow Performance Index (MEPI, 0 to 100 points). Radiographic loosening
was defined as a progressive radiolucent line of >1 mm that was
completely circumferential around the prosthesis. Results. The mean MEPI scores significantly improved from 40 (10 to 75)
points preoperatively to 95 (30 to 100) points at final follow-up
(p < 0.0001). Complications were noted in ten elbows (ten patients;
11%). Two had an intraoperative humeral fracture which was treated
by
We have compared the outcomes of the use of external
Aims. To synthesise the literature and perform a meta-analysis detailing
the longitudinal recovery in the first two years following a distal
radius fracture (DRF) managed with volar plate
External
Evaluate if treating an unstable femoral neck fracture with a locking plate and spring-loaded telescoping screw system would improve construct stability compared to gold standard treatment methods. A 31B2 Pauwels’ type III osteotomy with additional posterior wedge was cut into 30 fresh-frozen femur cadavers implanted with either: three cannulated screws in an inverted triangle configuration (CS), a sliding hip screw and anti-rotation screw (SHS), or a locking plate system with spring-loaded telescoping screws (LP). Dynamic cyclic compressive testing representative of walking with increasing weight-bearing was applied until failure was observed. Loss of fracture reduction was recorded using a high-resolution optical motion tracking system.Aims
Methods
We compared a new
We reviewed seven children with torticollis due to refractory atlanto-axial rotatory
Fractures of the scaphoid are most common in young men; immobilisation in a cast usually means a long period away from work and athletic activities. Early rigid
We treated 47 patients with a mean age of 57 years (22 to 88) who had a proximal humeral fracture in which there was a severe varus deformity, using a standard operative protocol of anatomical reduction,
Ununited fractures of the scaphoid with extensive bone resorption are usually treated by bone grafting and internal
In a prospective, randomised trial, we compared the use of three Ullevaal hip screws with that of two Hansson hook-pins in 278 patients with fractures of the femoral neck. Background factors were similar in both groups. Follow-up was for two years. There were no significant differences between the groups in length of time of surgery, hospital stay, general complications, mortality, pain or walking ability. Likewise, the rates of early failure of
An account is given of 38 patients with complicated tibial fractures who were treated by the Portsmouth method of external