Background

Bone preservation is desired for future revision in any knee arthroplasty. There is no study comparing the difference in the amount of bone resection when soft tissue balance is performed with or without computer navigation.

To determine the effect on bony cuts when soft tissue balance is performed with or without use of computer software by standard manual technique in total knee arthroplasty.

One hundred patients aged 50 to 88 years underwent navigated TKR for primary osteoarthritis. In group A, 50 patients had both soft tissue release and bone cuts done using computer-assisted navigation. In group B, 50 patients had soft tissue release by standard manual technique first and then bone cuts were guided by computer-assisted navigation.

In group A the mean medial tibial resection was 5 ± 2.3 mm and lateral was 8 ± 1 mm compared to 5 ± 2 mm (P = 0.100) and 8 ± 1 mm respectively in group B (P = 0.860). In group A the mean medial femoral bone cut was 9 ± 2.9 mm and lateral was 8 ± 2 mm as compared to 9.5 ± 2.9 mm (P = 0.316) and 10 ± 2.2 mm respectively in group B (P = 0.001). Average prosthesis size was 6 (range 3 to 8) in group A as compared to size 5 (range 2 to 7) in group B. Average navigation time in group A was 102 minutes (range 45 to 172) and in group B was 83 minutes (range 42 to 165, P = 0.031).

Our results show that performing soft tissue release and bone cuts using computer- assisted navigation is more bone conserving as compared to manual soft tissue release and bone cuts using computer navigation for TKR, thus preserving bone for possible future revision surgery.

Introduction: The aim of our study was to assess any difference in outcome between non-surgical and surgical treatment of displaced calcaneal fractures.

Materials and Methods: We studied 40 patients between 2000 to 2005 with displaced calcaneal fractures. Patients with significant co-morbidities were excluded. Two groups of 14 patients, surgery vs. no surgery were compared for age, sex, length of follow-up, fracture type by Essex-Lopresti classification and SF-36 outcome score. The non-surgical group underwent treatment with rest, ice, compression, elevation and the surgical group underwent fixation with an AO calcaneal plate through an extended lateral approach.

Results: There was no statistically significant difference between the surgical and conservatively treated groups for age, sex, time since injury and fracture type according to Essex-Lopresti but a highly statistically significant difference in SF-36 outcomes between the two groups favouring surgically treated calcaneal fractures.

Summary: Displaced fractures of the calcaneum are a significant injury affecting patients general health. In the literature controversy exists as to whether operative or non-operative treatment is better for this type of fracture.

Conclusion: Although the numbers are small, our study favours operative intervention, if possible, for this controversial fracture.

The aim of our study was to determine if the canal flare index of the proximal femur is a dependent factor in prosthetic failure after Austin Moore hemiarthroplasty.

We measured the canal flare index on A-P hip X-rays of 100 and 100 patients with failed and successful Austin Moore hemiarthroplasty respectively. We also measured the canal flare index of a control group of 100 patients without hip fractures. The canal flare index (CFI) is defined as the ratio of the width of the femoral canal at two levels: 20mm proximal to the centre of the lesser trochanter and the canal isthmus. Overall we reviewed 300 radiographs. The study group consisted of 68 males and 232 females. In the failed Austin Moore group there were 62 patients (62%) with loosening, 28 patients (28%) with dislocations and 10 patients (10%) with periprosthetic fractures. The canal flare index of the proximal femur was significantly higher in patients who had persistent thigh pain with radiological loosening in comparison the successful and control groups. (3.3 vs 2.6; 3.2 vs 2.7 respectively: p< 0.001). On the other hand patients with periprosthetic fractures had a lower canal flare index in comparison with the successful and control groups (2.1 vs 2.6; 2.1 vs 2.7 respectively: p< 0.001). However there was no differences in the CFI of patients with dislocations compared with successful (2.4 vs 2.6;p=0.1) and control groups (2.4 vs 2.7;p=0.2). This remained the same when controlled for age and sex in a logistic regression analysis.

Conclusion: The CFI can identify patients prone to persistent thigh pain who present as radiological loosening and to periprosthetic fractures and an alternative cemented prosthesis should be considered in this group of patients

Limb lengthening by callus distraction and external fixation has a high rate of complications. We describe our experience using an intramedullary nail (Fitbone) which contains a motorised and programmable sliding mechanism for limb lengthening and bone transport. Between 2001 and 2004 we lengthened 13 femora and 11 tibiae in ten patients (seven men and three women) with a mean age of 32 years (21 to 47) using this nail. The indications for operation were short stature in six patients and developmental or acquired disorders in the rest.

The mean lengthening achieved was 40 mm (27 to 60). The mean length of stay in hospital was seven days (5 to 9). The mean healing index was 35 days/cm (18.8 to 70.9). There were no cases of implant-related infection or malunion.