Page 192 - Reconstructive Techniques in Musculoskeletal Tumor Surgery

Chapter 9
Structural complications (Henderson type 3) occurred in 15 reconstructions (15 of 110 [14%]) after a mean of three years (range, 0.0 – 13.5 years). These included six complications of the locking mechanism: three fractures, two instances of wear, and one unlocking of the locking mechanism. Four occurred in PEEK-OPTIMA locks. There were four periprosthetic fractures occurring at three weeks, eight months, 20 months, and six years, respectively. There were three fractures of the femoral component, two with a 12-mm core diameter and a defect of 17.5 and 21.5 cm and one with a 16-mm core diameter stem with a defect of 15.5 cm. These stem fractures occurred two, four, and four years, respectively. There was one fractured insert and one implant rotation deformity.
Two prosthetic fractures and one periprosthetic fracture resulted in revision or removal of the entire implant; others were managed either conservatively or with limited revision procedures such as xation of the periprosthetic fracture with a small plate, relocking of the locking mechanism, or revision of the locking mechanism. In addition, undisplaced ssure fractures occurred during implantation in 11 reconstructions: nine distal femoral replacements and two proximal tibial replacements. All healed uneventfully. Replacement of the bushings was performed in nine reconstructions (nine of 110 [8%]) after a mean of six years (range, 0.1 – 18 years).
Non-mechanical Complications
Deep infections (Henderson type 4) occurred in 15 reconstructions (15 of 110 [14%]). According to the Henderson classi cation, nine infections were early (<2 years after implantation [nine of 110, 8%]) and six were late (six of 110 [5%]). Three early-infected implants were retained. Three late infections occurred after operative intervention for another complication; of these, two were retained.
Local recurrences (Henderson type 5) occurred in ten patients (ten of 101 [10%]) after a mean of two years (range, 0.8 – 6 years). All patients who developed a local recurrence had clear surgical margins during the index resection. Two patients had received radiotherapy (one leiomyosarcoma, one high-grade osteosarcoma of an unusual subtype). Treatment consisted of ablative surgery in seven patients and of a second limb-salvaging resection (without removing the implant) in two. In one patient no further treatment was undertaken as a result of a poor prognosis. Focusing on patients without prior resections, local recurrences occurred in ve of 39 patients with an extra-articular resection (13%) and in four of 45 patients with an intra-articular resection (9%) (p = 0.561).
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