[Treatment of femoral and tibial septic pseudarthrosis by internal lengthening. Apropos of 24 cases]. / Le traitement des pseudarthroses fémorales et tibiales septiques par allongement interne. A propos de 24 cas.

Twenty two patients aged 18 to 47 years were treated for 24 infected bone defects and nonunions (6 femora and 16 tibiae) by radical resection of the necrotic bone and distraction osteogenesis techniques to regenerate the excised bone. Nonunion, infection, limb shortening, deformity, and osteoporosis were all addressed simultaneously. All patients underwent either bifocal or trifocal internal lengthening by bone transport technique of sliding a bone fragment, producing distraction osteogenesis behind it until the defect was bridged. The mean bone defect was 8.2 cm, with a range up to 16 cm. Eradication of the infection was achieved in all cases prior to the removal of the fixator. Problems with union requiring bone graft augmentation were encountered in three patients. One patient, who sustained a refracture, underwent an amputation. The mean time to union was 4.4 months, if the time was taken from the day the intercalary segment came in contact with the targed segment. Deformity and length inequality were corrected successfully in the majority of the patients. The bone result was excellent in 15 cases, good in 7, fair in one, and poor in one. The functional result was excellent in 11 cases, good in 8, fair in 3, and poor in 2. Distraction osteogenesis treatment seems to be superior to any other method used for treatment of infected bone defects and nonunions, especially in terms of eradication of osteomyelitis and quality of bone union. However, the ability to achieve excellent bone result in even the worst infected bone defects and nonunions does not guarantee a favourable functional result, unless the patient has an acceptable neurovascular status.

Simultaneous bilateral trochanteric and subtrochanteric fractures: case reports.

We report three cases of very rare simultaneous bilateral trochanteric and subtrochanteric fractures. These combined fractures are severe, life-threatening injuries that should be treated according to the principles of treatment of multiple injuries. Adequate fluid resuscitation, early one-stage internal fixation of both fractures, and early mobilization of the patient are the major determinants of successful outcome.

Traumatic hemipelvectomy. A case report and comments on associated injuries.

The twenty-fifth reported case of survival following traumatic hemipelvectomy is presented. Our patient is the fourth female survivor and the second who escaped associated injuries to either the genito-urinary system or the rectum.

Treatment of subtrochanteric fractures of the femur: a study of intramedullary compression nailing.

The results of prospective treatment of 31 patients with subtrochanteric fractures using the Derby intramedullary nail are presented. The nail design, plus cerclage wires in unstable cases, allows axial compression of the fracture, to give rigid fixation and load-sharing between bone and nail. Twenty-seven patients were followed up for an average of 21.7 months. There were no mechanical failures of the nails, and all 27 fractures united, two in minimal varus. Relatively early mobilization of the patients with isolated fractures occurred.

The effects of medullary reaming on the torsional strength of the femur.

The authors have investigated the effect on the torsional strength of the bone of reaming the medulla of the femur from 12 to 16 mm in steps of 1 mm. Five groups of femurs, with 10 pairs in each, were tested comparatively in torsional loading and the torque required to cause fracture and the angle through which the bone had twisted at fracture were directly recorded for each pair. The results of maximum torque at failure (expressed as a proportion of the same parameter for the unreamed femur) plotted against the ratio of bone shaft diameter to reamed diameter showed a good correlation. The proportional maximum torque was found to range from 0.63 (at 12 mm) to 0.36 (at 16 mm) with a sharp transition between 14 and 15 mm. This drastic reduction was felt to be important for both the surgeon and the patient.

Derby intramedullary nail: further biomechanical comparison.

This paper is the second part of a study into the mechanical effectiveness of a new intramedullary femoral nail (the Derby nail). The results of three point bending tests have shown that the Derby nail is stronger and stiffer than both the K and Zickel nails and offers advantages over the AO plate, despite the latter's higher load carrying ability when used on the compressively loaded bone face. Previous work by the authors has shown the Derby nail to be superior in torsional loading and it is felt that this intramedullary device offers sound clinical advantages over the other designs, this being confirmed by extensive clinical trials.

Treatment of fractures of the distal third of the femur. A prospective trial of the Derby intramedullary nail.

We report a prospective study of 26 cases of fracture of the distal third of the femur treated with the Derby intramedullary nail. This new design controls rotation and allows compression of the fracture, permitting early weight-bearing. All the fractures united in good position within four months, 12 of them with minimal external callus. There were no implant failures and the only serious complication was one case of deep infection.

Medullary femoral nailing of pathological fractures using the Derby nail--a preliminary report of 22 cases.

A new medullary femoral nail is reported. The device provides dynamic compression, producing rigid stabilization with resistance to rotational stresses. We present 22 cases of pathological fractures of the femur treated by the Derby nail. Rigid fixation was achieved with no sepsis, loosening or implant failure at the latest follow-up or death. The mean time spent in hospital was 20 days and patients took full weight, on average, by the 9th postoperative day.

Derby intramedullary nail--a biomechanical comparison.

This paper describes the design and function of the Derby intramedullary nail and its biomechanical testing, comparing it with the K nail and reamed unfractured femurs. The Derby nail is designed to transmit torsional loads and apply compression to the fracture site using a sliding proximal collar and distal extendable 'wings'. Femurs fixed with Derby, K and Zickel nails and AO plates were tested in torsion and the rotation and torsional load at failure recorded and compared with unfractured control femurs. The results show that the strength of the Derby nail in torsion is approximately equal to 4 times and the energy to failure 2.3 times that of the K nail.