Aims

Patients undergoing femoral lengthening by external fixation tolerate treatment less well when compared to tibial lengthening. Lengthening of the femur with an intramedullary device may have advantages.

Aims

This study describes the Osseointegration Group of Australia’s Accelerated Protocol two-stage strategy (OGAAP-1) for the osseointegrated reconstruction of amputated limbs.

Internal lengthening devices in the femur lengthen along the anatomical axis, potentially creating lateral shift of the mechanical axis. We aimed to determine whether femoral lengthening along the anatomical axis has an inadvertent effect on lower limb alignment. Isolated femoral lengthening using the Intramedullary Skeletal Kinetic Distractor was performed in 27 femora in 24 patients (mean age 32 years (16 to 57)). Patients who underwent simultaneous realignment procedures or concurrent tibial lengthening, or who developed mal- or nonunion, were excluded. Pre-operative and six-month post-operative radiographs were used to measure lower limb alignment. The mean lengthening achieved was 4.4 cm (1.5 to 8.0). In 26 of 27 limbs, the mechanical axis shifted laterally by a mean of 1.0 mm/cm of lengthening (0 to 3.5). In one femur that was initially in varus, a 3 mm medial shift occurred during a lengthening of 2.2 cm.

In a normally aligned limb, intramedullary lengthening along the anatomical axis of the femur results in a lateral shift of the mechanical axis by approximately 1 mm for each 1 cm of lengthening.

We report the results of intramedullary leg lengthening conducted between 2002 and 2009 using the Intramedullary Skeletal Kinetic Distractor in 69 unilateral lengthenings involving 58 femora and 11 tibiae. We identified difficulties that occurred during the treatment and assessed whether they were specifically due to the implant or independent of it. Paley’s classification for evaluating problems, obstacles and complications with external fixators was adopted, and implant-specific difficulties were continuously noted. There were seven failures requiring premature removal of the device, in four due to nail breakage and three for other reasons, and five unsuccessful outcomes after completion of the lengthening. In all, 116 difficulties were noted in 45 patients, with only 24 having problem-free courses. In addition to the difficulties arising from the use of external fixators, there were almost the same number again of implant-specific difficulties.

Nevertheless, successful femoral lengthening was achieved in 52 of the 58 patients (90%). However, successful tibial lengthening was only achieved in five of 11 patients (45%).

Between October 2001 and September 2009 we lengthened 242 lower-limb segments in 180 patients using the Intramedullary Skeletal Kinetic Distractor (ISKD). Mechanical failure was defined either as breakage of the ISKD or failure of the internal mechanism to activate. Retrieved nails which failed mechanically were examined by the manufacturer for defects. In all, 15 ISKDs in 12 patients (13 limbs) failed mechanically representing an overall failure rate of 6.2%, with fracture of the device occurring in ten of the 15 failures. Two nails in one patient failed to lengthen and had to be replaced. The manufacturer detected an error in the assembly of the nail, which prompted a wide recall. One nail jammed after being forcefully inserted, and two nails failed to lengthen fully. Lengthening was achieved in all 12 patients, although three required a second operation to exchange a defective nail for a new, functioning device.

The ISKD is a complex mechanical device which lengthens by the oscillation of two telescopic sections connected by a threaded rod. The junction between these sections is surrounded by a keyring collar. This keyring collar is the weakest part of the device.

We present the results of the surgical correction of lower-limb deformities caused by metabolic bone disease. Our series consisted of 17 patients with a diagnosis of hypophosphataemic rickets and two with renal osteodystrophy; their mean age was 25.6 years (14 to 57). In all, 43 lower-limb segments (27 femora and 16 tibiae) were osteotomised and the deformity corrected using a monolateral external fixator. The segment was then stabilised with locked intramedullary nailing. In addition, six femora in three patients were subsequently lengthened by distraction osteogenesis. The mean follow-up was 60 months (18 to 120). The frontal alignment parameters (the mechanical axis deviation, the lateral distal femoral angle and the medial proximal tibial angle) and the sagittal alignment parameters (the posterior distal femoral angle and the posterior proximal tibial angle) improved post-operatively. The external fixator was removed either at the end of surgery or at the end of the lengthening period, allowing for early mobilisation and weight-bearing. We encountered five problems and four obstacles in the programme of treatment.

The use of intramedullary nails prevented recurrence of deformity and refracture.

Our aim was to evaluate the results of triple arthrodesis, performed without the use of supplementary bone graft. We carried out a retrospective review of 100 consecutive triple arthrodeses. All the operations had been performed by the senior author (TSS) using a standard technique. Only local bone graft from the excised joint surfaces had been used, thereby avoiding complications at the donor site.

The mean age of the patients at surgery was 58 years (18 to 84). The mean time to union was 5.1 months (3 to 17). There were 75 good, 20 fair and five poor results. There were four cases of nonunion.

Our study has shown that comparable rates of union are achieved without the need for supplementary bone graft from the iliac crest or other donor site.

We performed nine metatarsal and three proximal phalangeal lengthenings in five patients with congenital brachymetatarsia of the first and one or two other metatarsal bones, by a one-stage combined shortening and lengthening procedure using intercalcary autogenous bone grafts from adjacent shortened metatarsal bones. Instead of the isolated lengthening of the first and the other metatarsal bones, we shortened the adjacent normal metatarsal and used the excised bone to lengthen the short toes, except for the great toe, to restore the normal parabola. One skin incision was used. All the operations were performed bilaterally and the patients were followed up for a mean period of 69.5 months (29 to 107). They all regained a nearly normal parabola and were satisfied with the cosmetic results. Our technique is straightforward and produces good cosmetic results. Satisfactory, bony union is achieved, morbidity is low, and no additional surgery is required for the removal of metal implants

Vascular malformations are rare congenital lesions which often have associated skeletal changes. Over a period of ten years, 90 patients at our clinic had a vascular anomaly of the lower limb, examined by either CT or MRI. Of these, 18 (20%) had bony involvement. A questionnaire was sent to these patients (8 men, 10 women) to evaluate their age of presentation, initial symptoms and current complaints. Radiological imaging revealed 15 low- and three high-flow lesions. The mean age at presentation to a physician was six years of age. Pain was the most common complaint. Disparity in leg length of 2 cm or more was observed in ten patients. Of the 16 patients with muscle infiltration, 13 had four or more muscles involved. Treatment by resection alone would require radical surgery

We performed one-stage lengthening using intercalary autogenous bone graft in 34 metatarsals and seven proximal phalanges in 21 patients with congenitally short metatarsals. At operation, in order to decrease the tension in the surrounding soft tissues, we gradually distracted the osteotomies of the affected bones for 20 to 30 minutes. The patients, all women, were followed up for a mean period of 2.1 years (1 to 6.5). The average gain in length for the 34 metatarsal procedures was 14 mm (6 to 21), equivalent to an increase of 32% (11 to 51), and for the seven proximal phalangeal lengthenings 8 mm (5 to 11), an increase of 54% (47 to 65). There was no evidence of neurovascular impairment. The technique of gradual distraction during operation is simple and effective. It overcomes the disadvantages of one-stage lengthening such as a small gain in length and neurovascular damage