Purpose of the study: Data are scarce in the literature on lower limb length discrepancy (LLD) after total hip arthroplasty (THA). This parameter is difficult to evaluated intraoperatively with conventional instruments. In addition LLD after THA is often poorly tolerated and can be a source of legal suites. The purpose of this work was to evaluate the contribution of navigation for controlling lower limb length during implantation of a THA.

Material and method: Sixty-five THA were implanted in 63 patients, aged 35–81 years, using a passive navigation system based on a function reference system which controlled the position of the implants and the length of the operated leg. Limb length and femur length were measured radiographically on both sides before and after surgery. The horizontality of the acetabular U lines was measured on the AP view of the pelvis. An independent radiologist made all measurements.

Results: The precision of the radiographic measurements was < 3 mm. The precision of the navigation system was < 3 mm. Subjectively, 56 of the 63 patients did not have a feeling of LLD preoperatively. No un programmed difference > 3 mm in leg length between the before and after THA measurements was noted. Preoperatively, seven patients complained of lower back pain related to LLD and three had a compensated shoe measuring 5 to 10 mm. These latter three patients had a horizontal pelvis (< 1) after THA. In all cases, the overall length correction was achieved by adapting the length of the neck.

Discussion: In our opinion, not all radiologically determined and/or clinically perceived LLD should be corrected. Care must be taken to ensure that permanent preoperative hip flexion does not perturb limb length measurements.

Conclusion: The navigation system used in this series for the implantation of THA was able to control operated limb length with precision.

Purpose of the study: In rheumatoid arthritis, 15 to 28% of patients present hip involvement, sometimes requiring arthroplasty. The purpose of this work was to evaluate the usefulness of cementless implants for patients with inflammatory hip disease, recognising that cemented implants are widely used for this indication.

Material and method: The was a retrospective series of 63 consecutive first-intention cementless total hip arthroplasties (THA) implanted from April 1986 to June 2007 in 48 patients (35 females), mean age 55 years (range 19–87), with rheumatoid arthritis. The majority of these patients were on a two-drug regimen of corticosteroids and methotrexate. Twelve patients were taking anti-TNF alpha. In all cases, both the femoral and acetabular elements of the implant were inserted without cement. The Postel-Merle-d’Aubligné (PMA) score was used for clinical assessment (preop, postop, last follow-up). Signs of loosening were noted on the plain x-rays.

Results: Mean follow-up was 103 months (range 12–264). There was a significant improvement in the PMA score. There were two intraoperative complications (calcar fissuration). Twenty-one cases (33%) exhibited acetabular protrusion requiring autologous bone graft. At last follow-up, all acetabular grafts were incorporated. At last follow-up there were no cases of deep infection. Three cases (4.8%) required uniplar acetabular revision for aseptic loosening at 127, 145, and 217 months after initial implantation. Major wear of the polyethylene insert was observed in all hips, associated with retroacetabular osteolysis. A new cementless implant was used for the revision in two cases, with satisfactory outcome a mean 41 months from revision. In addition, four cups and three stems presented unchanged lucent lines and had not been revised at last follow-up.

Discussion: THA is a therapeutic option for the rheumatoid hip. Long-term outcome with cemented THA has shown an increased incidence of deep infections and aseptic loosening in this context. At mean 9 years follow-up, we have had very encouraging results with cementless implants in this context.

Purpose of the study: The rate of intra and postoperative complications is generally high after surgery for neurogenic paraosteoarthropathy, also termed hetero-topic ossification.

Material and methods: We present a series of 60 cases of osteoma involving the hip joint, analyzing complications in comparison with data in the literature.

Results and discussion: Vascular complications (n=7): one required suture of the common femoral artery, three ligature of the deep femoral artery, two ligature of the deep femoral vein and one ligature of the collateral branches of the deep femoral vessels. Mean intraoperative blood loss was 1300 cc. None of the vascular complications gave rise to death or amputation. Early septic complications (n=4): three occurred after simple resection of the ossification and cured after surgical revision and antibiotics with no major impact on joint motion; one occurred after a procedure for resection of the ossification plus total hip arthroplasty and led to ankylosis of the hip joint but cured after surgical revision and prolonged antibiotic therapy. Sepsis was favored by a long hemorrhagic surgical procedure in patients at risk. Neurological complications (n=0): such complications are greatly feared but rare. Posterior ossifications expose the sciatic nerve to injury but generally displacement the nerve rather than enclosing it in the osteoma. Fracture complications (n=1): the outcome was favorable, both in terms of bone healing and joint motion. A classical complication mentioned in the literature and synonym to recurrent ossification or invalidating residual stiffness. Most are favored by ankylosis, osteoporosis, immobilization and a particularly dynamic surgeon. Recurrences (n=6): all were posttraumatic with a delay from accident to surgery ≥ 18 months.

Conclusion: Complications are related to the localization of the osteoma (relations with nerves and vessels), associated osteopathy, and the complete or partial joint stiffness. Preoperative imaging (x-rays and computed tomography with contrast injection) should localize the osteoma, keeping in mind that certain localizations create preferential conditions for certain risks. An analysis of the topography of the paraosteoarthropathy should enable the surgeon to choose the most appropriate approach. Intraoperatively, risk assessment can usefully anticipate complications which always compromise functional outcome.

Purpose: Surgery is the mainstay treatment for chondro-sarcoma. About 35–40% of these tumours are located in the pelvis. Treatment requires significant sacrifices to ensure acceptable survival.

Material and methods: This retrospective analysis of ten patients treated between 1993 and 2001 for pelvic chon-drosaromas was undertaken to examine survival and functional sequelae as a function of treatment and tumour grade. All patients had primary chondrosarcoma. The population included seven men and three women, mean age 50.9 years (range 28–77). Mean survival was 39.7 months.

A biopsy was obtained in all cases (seven under scan guidance). Six patients required complementary surgical biopsy. According to the O’Neel and Ackermann classification, the tumours were grade I in five patients, grade II in two, grade III in three. Tumour classification according to the Enneking topography was: zone I one patient, zone I and II one patient, zone I+II+III one patient, zone II three patients, zone II+III three patients, and zone III one patient. Careful search for extension failed to identify metastasis preoperatively in any patient. For six patients, tumour resection was performed without reconstruction. Resection was associated with a Pugent reconstruction in three patients. All patients were reviewed with an AP view of the pelvis and a chest x-ray.

Results: In sano resection was achieved in eight out of nine patients. For the ninth patient, resection was marginal according to the pathology report. Postoperative survival revealed the presence of metastasis in three patients. One patient developed recurrent tumour. At last follow-up, two patients had died and one had multiple metastases. Seven are currently disease free. Early postoperative complications occurred in 80% of the patients.

Discussion: Currently, surgery remains the treatment of choice for pelvic chondrosarcoma, despite the major perioperative morbidity. Reconstruction, if attempted must always respect the rules of carcinological resection. Reconstruction does not appear to be mandatory since the rate of secondary and late complications remains particularly high in the case of extensive reconstruction. Histological grade, tumour size and quality of surgical resection are the predominant prognostic factors.