Outcome of surgery for recurrent patellar dislocation based on the distance of the tibial tuberosity to the trochlear groove.

We evaluated the outcome in a series of patients with recurrent patellar dislocation who had either medial transfer of the tibial tuberosity and lateral release or an isolated lateral release as the primary treatment. The decision to use one or other procedure was based on a pre-operative distance between the tibial tuberosity to the trochlear groove (TTTG) of less than 10 mm to include the tibial tuberosity transfer in addition to the lateral release. Between April 2002 and December 2006, 49 patients (63 knees) underwent one of these procedures. A total of 35 patients (46 knees) was evaluated at a mean of 38 months (13 to 71) post-operatively. Medial transfer of the tibial tuberosity was performed in 33 knees and isolated lateral release in the remaining 13. Evaluation included the International Knee Documentation Committee (IKDC), the Kujala and the Short-form 36 scores. From the tibial tuberosity group 23 knees also underwent radiological examination at follow-up. There were further episodes of patellar dislocation in six of the 46 knees available for review. Further dislocation was noted in five of 33 knees (15.2%) in the tibial tuberosity transfer group and in one of 13 knees (7.7%) in the lateral release group. The mean subjective IKDC score was 80.4 (sd 11.6), the mean Kujala score 88 (sd 8.2) and the mean objective IKDC score was 79% normal and 21% nearly normal. The mean post-operative TTTG distance in the tibial tuberosity transfer group was 8.9 mm (3.2 to 15.7) compared with the mean pre-operative value of 16.8 mm (12.2 to 24.4).

Portal circulation aneurysms: two case reviews.

Venous aneurysms of the superior mesenteric vein and portal vein are an uncommon occurrence and often an incidental finding. They can also be associated with hepatocellular disease and portal hypertension. We present CT and ultrasound findings of these entities. The management of venous aneurysms is generally conservative with serial imaging.

Primary "brown pigment" bile duct stones.

Bile duct stones from 42 patients were morphologically and chemically analysed. The calculi from 27 patients had important primary bile duct stone (PBDS) features, consisting of a general ovoid shape and fragile structure, with alternating light and dark brown pigmented layers on cross-section. Chemically these stones contained low levels of cholesterol, with high levels of bilirubin and calcium. Subsequent infrared spectroscopy analysis showed that calcium bilirubinate and calcium palmitate were the only calcium salts present. Calcium palmitate was prominent in the light brown layers. A morphological and chemical comparison with gallbladder stones showed that bile duct "stasis stones" were similar in morphological and chemical composition to the brown pigment gallbladder calculi. However, they were distinct from most gallbladder stones, indicating that primary bile duct calculi have an aetiology that is different to 90% of gallbladder calculi. Primary bile duct calculi were observed to occur with or without the presence of a gallbladder, and more interestingly, in the bile duct of two patients with cholesterol gallbladder stones. Bile duct bile of patients with primary choledocholithiasis were always moderately to profusely infected and with abundant calcium bilirubinate precipitation. Moreover, this study has shown that PBDS chemical analyses profiles were consistent and correlated well with their defined morphology. Consequently, PBDS may be accurately identified at the time of operation by morphology. An important aetiological factor would appear to be infection, which would seem to promote bile duct bile stasis and eventual stone growth.

Effect on pregnancy on gallstone formation.

An ultrasound study was carried out to determine the incidence of gallstone formation during pregnancy. One hundred and thirty seven pregnant women attending antenatal clinics were studied; 70 women were primigravidas and 67 were 1 para or more. An ultrasound of the gallbladder was carried out at 20 weeks or less of gestation and a repeat of ultrasound examination was performed soon after delivery. Five women had gallstones diagnosed before pregnancy; 1 of these was a primigravida, the other 4 were para 1 or more. None of the women developed gallstones during pregnancy. This finding suggests that pregnancy is unlikely to be an important factor in gallstone formation.

Bacteria and gallstone nucleation.

This preliminary study reports for the first time that there might be a possible association between bacteria and the aetiology of some cholesterol calculi. The gall-bladder biles from 225 cholecystectomy patients underwent bacteriological and microscopic study. Cholesterol calculi from 13 patients (10.2%) were observed to be associated with gall-bladder bile profusely infected with at least one bacterial species that was shown to possess beta-glucuronidase activity, an enzyme that is thought to promote calcium bilirubinate precipitation in bile. Concomitantly, the associated gall-bladder bile was 'high' in calcium bilirubinate precipitation and the precipitate was also detected in the centre of the gallstones. Moreover, in approximately half of these patients (six of 13), the cholesterol gallstones' nuclear areas also contained calcium palmitate, which is also thought to be due to bacterial activity. The results also support the hypothesis that bacteria with active beta-glucuronidase (for example, Escherichia coli) can significantly influence the aetiology of brown pigment gallstones. In contrast, bacteria were observed to have no role in black pigment gallstone formation, as their associated gall-bladder biles were always observed to be sterile.

Gallstones at autopsy and cholecystectomy: a comparative study.

An examination of 613 post-mortems gave a prevalence of biliary disease at autopsy of 36.5%, higher than reported previously in Australia. This consisted of an asymptomatic gallstone prevalence of 18.9%, with a further 5.7% of the autopsies having granular biliary sludge and 11.9% having had a previous cholecystectomy. Although the rate of occurrence of cholesterol gallstones was approximately half that of the pigment gallstones and pigment biliary sludge combined, no significant association between the sex of the postmortems and stone type was observed at autopsy (chi 2(1) = 0.1: P greater than 0.05). The ratio of biliary disease between females and males was approximately 2:1. Gallstones and biliary sludge from 310 cholecystectomy patients showed that cholesterol gallstones were approximately twice as common in men, and approximately six times as common in women than pigment gallstones. In this group of patients there was a significant association between the sex of the patient and the rate of occurrence of stone type. The rate of occurrence of cholesterol gallstones was significantly higher than pigment gallstones in both the males and females at cholecystectomy (chi 1(2) = 18.97; P less than 0.0001). A female to male ratio of approximately 2:1 was also observed. A statistically significant higher rate of pigmented biliary disease was observed at autopsy than at cholecystectomy. (chi 2 = 101.0; P less than 0.0001). Analyses on biliary sludge, a filterable, fine granular pigmented material in bile, suggest that it may be the direct precursor for a number of different gallstone types.