We tested four types of surgical repair for load to failure and distraction in a bovine model of Achilles tendon repair. A total of 20 fresh bovine Achilles tendons were divided transversely 4 cm proximal to the calcaneal insertion and randomly repaired using the Dresden technique, a Krackow suture, a triple-strand Dresden technique or a modified oblique Dresden technique, all using a Fiberwire suture. Each tendon was loaded to failure. The force applied when a 5 mm gap was formed, peak load to failure, and mechanism of failure were recorded. The resistance to distraction was significantly greater for the triple technique (mean 246.1 N (205 to 309) to initial gapping) than for the Dresden (mean 180 N (152 to 208); p = 0.012) and the Krackow repairs (mean 101 N (78 to 112; p < 0.001). Peak load to failure was significantly greater for the triple-strand repair (mean 675 N (453 to 749)) than for the Dresden (mean 327.8 N (238 to 406); p < 0.001), Krackow (mean 223.6 N (210 to 252); p <  0.001) and oblique repairs (mean 437.2 N (372 to 526); p < 0.001). Failure of the tendon was the mechanism of failure for all specimens except for the tendons sutured using the Krackow technique, where the failure occurred at the knot.

The triple-strand technique significantly increased the tensile strength (p = 0.0001) and gap resistance (p = 0.01) of bovine tendon repairs, and might have advantages in human application for accelerated post-operative rehabilitation.

We examined whether a selective cyclooxygenase-2 (COX-2) inhibitor (celecoxib) was as effective as a non-selective inhibitor (ibuprofen) for the prevention of heterotopic ossification following total hip replacement. A total of 250 patients were randomised to receive celecoxib (200 mg b/d) or ibuprofen (400 mg t.d.s) for ten days after surgery. Anteroposterior radiographs of the pelvis were examined for heterotopic ossification three months after surgery. Of the 250 patients, 240 were available for assessment. Heterotopic ossification was more common in the ibuprofen group (none 40.7% (50), Brooker class I 46.3% (57), classes II and III 13.0% (16)) than in the celecoxib group (none 59.0% (69), Brooker class I 35.9% (42), classes II and III 5.1% (6), p = 0.002). Celecoxib was more effective than ibuprofen in preventing heterotopic bone formation after total hip replacement.

Purpose: Heterotopic ossification is a recognised complication after total hip arthroplasty. Prevalence can reach 53%, particularly if prophylaxis is not given, leading to postoperative pain and limiting the functional prognosis. Non-steroidal antiinflammatory drugs have proven efficacy but also present the risk of gastroduodenal toxicity making postoperative administration hasardous. Recently, selective COX-2 inhibitors have been shown to have a similar antiinflammatory activity with a clear reduction in gastrointestinal disorders. We hypothesised that selective COX-2 inhibitors could be as effective as classical NSAID for the prevention of heterotopic ossifications.

Material and methods: This clinical trial was conducted according to a prospective randomised protocol comparing a group of patients given prophylaxis with Celecoxib (Celebrex®) and another group of patients given ibuprofen (Brufen®). All patients scheduled for total elective prostheses were radomised in a prospective manner to one of the two groups, either Celecoxib 200mg b.i.d. or ibuprofen 400mg t.i.d. for ten immediate postoperative days. Radiological assessment was performed by two independent investigators blinded to the study (an orthopaedic surgeon and a radiologist) who scored calcifications according to the Brooker classification (type I to IV) at three months after surgery. Reproducibility of radiogram reading was tested and analysed with a kappa test K=0.74).

Results: Two hundred ten patients were randomised and 73 have had their three-month radiograms. The Cele-coxib group included 37 patients: 24 with Brooker stage 0, eleven with stage 1, two with stage 2. The ibuprofren group included 42 patients, 15 with Brooker 0, 16 with Brooker 1; nine with Brooker 2 and two with Brooker 3. The statistical analysis will be performed at the end of this study (June 2002).

Discussion: The preliminary results show that Celecoxib appears to have the same efficacy as ipubrofen for the prevention of heterotopic ossification after total hip arthroplasty. There was a clear trend in favour of Celecoxib.

We report the 12 to 74 month results of our mark I saddle prosthesis after its use as a salvage device for gross loss of pelvic bone stock in 76 patients with failed hip arthroplasties. The implant transmits load between iliac bone and bare polish chrome-cobalt. Our clinical and radiological results indicate that a useful and stable articulation can be achieved in most cases, provided that continued deep infection can be avoided. The appearance of radiological sclerosis at the bearing site in successful cases seems to indicate that significant late migration will not occur. Based on our experience with the mark I prosthesis we have designed and developed a mark II model which has freedom of axial rotation of the saddle. Our early results in 40 cases show a significant improvement over the results which could have been predicted for the mark I device.