Is the position of dual-mobility cup in THA for femoral neck fractures optimal? A retrospective study.

INTRODUCTION: Few studies have examined the relationship between the indication of total hip arthroplasty (THA) and the quality of its technical achievement. Implants mispositioning could happen more frequently while THA is performed on acute proximal femur fracture cases. The purpose of this study was to compare the frontal inclination (FTA) of double-mobility cups (DMC) in patients undergoing THA for hip osteoarthritis or fracture. MATERIALS AND METHODS: This retrospective study included all patients undergoing THA for hip fracture or hip osteoarthritis. The surgical protocol was identical in all patients and included a systematic DMC implantation. In the postoperative period, the FTA was measured on anteroposterior pelvic radiographs and compared between groups. Malposition was defined for FTA values outside the 35°-55° range. RESULTS: The study included 97 patients: 33 men, mean age: 78.8 years, 45 fractures. The misalignment rate was 55% after THA for fracture versus 33% for hip osteoarthritis (p = 0.02). The mean FTA value was 39° for "fracture" and 43° for "hip osteoarthritis" groups (p = 0.052). The risk for hip dislocation, surgical revision for mechanical or infectious cause was identical in both groups. DISCUSSION: Misalignment was more frequent when THA was achieved for an acute proximal femur fracture. Several explanations can be proposed: lesser bone quality, incomplete removal of upper acetabular osteophytes which can lead to excessive horizontalization of the cup and surgical procedure performed by younger surgeons in "fracture group". These misalignments don't cause more mechanical complications in the first months after surgery.

Correction of pelvic obliquity in neuromuscular spinal deformities using the "T construct": results and complications in a prospective series of 60 patients.

BACKGROUND: We present the results of a prospective series of 60 patients treated for neuromuscular spinal deformities with an original spinopelvic construct using two sacral screws and two iliac screws. Clinical and radiological results obtained with this new surgical technique were studied and discussed according to the epidemiological data and relevant literature. METHODS: From January 2008 to June 2010, the clinical data of every patient who underwent spinopelvic fixation for treatment of a neuromuscular spinal deformity were recorded prospectively. RESULTS: Sixty patients were operated on during the study period. Spinal correction and fusion was performed by posterior approach. In six patients with a residual spinopelvic imbalance more than 15° on lateral preoperative bending films, an anterior release of the thoracolumbar junction was performed on the same day, before posterior correction. Preoperative pelvic obliquity (PO) ranged from 4° to 44° (mean 21.6°). Postoperative pelvic obliquity ranged from 0° to 14 (mean 4.6°). No significant loss of correction was noted at the last follow-up. One patient died 3 months after the initial procedure due to respiratory compromise. 11 patients had early postoperative infections of the posterior approach. CONCLUSIONS: Despite a high rate of infectious complications, optimal correction of pelvic obliquity requires extension of spinal instrumentation to the pelvis. Spinopelvic fixation remains a difficult challenge in neurological patients with hypotrophy. We think that pelvic fixation with the "T construct" did provide effective and improved spinal stabilization in these patients, while reducing the need for a postoperative cast or brace. As a result, patients had a favourable postoperative course with early mobilization and return to a comfortable sitting position.

The "T-construct" for spinopelvic fixation in neuromuscular spinal deformities. Preliminary results of a prospective series of 15 patients.

BACKGROUND: We present the results of a prospective series of 15 patients treated for neuromuscular spinal deformities with an original spinopelvic construct using two sacral screws and two iliac screws. Results were compared to a prospective cohort of 62 patients treated for neuromuscular spinal deformities by spinopelvic fixation using iliosacral screws. METHODS: From November 2005 to June 2007, the clinical data of every patient who underwent spinopelvic fixation for treatment of a neuromuscular spinal deformity were recorded prospectively. RESULTS: Fifteen patients weighting less than 35 kg were operated on with a special segmental construct using two sacral screws and two iliac screws for pelvic anchorage. Sixty-two patients had spinopelvic fixation using iliosacral screws. Severity of the curve (Cobb angle) and reducibility were statistically equal in both groups. Operative time and blood loss were statistically identical in both groups. Curve correction was similar in both groups and postoperative pelvic obliquity ranged between 2° and 4°. No significant loss of correction was noted at the last follow-up. Fifteen patients had early postoperative infection of the posterior wound requiring re-operation. CONCLUSIONS: Despite a high rate of infectious complications, optimal correction of pelvic obliquity requires extension of spinal instrumentation to the pelvis. Pelvic fixation with the "T-construct" did provide effective and improved spinal stabilization in these patients, while reducing the need for a postoperative cast or brace. As a result, patients had a favorable postoperative course with early mobilization and return to a comfortable sitting position.

Spinopelvic fixation with iliosacral screws in neuromuscular spinal deformities: results in a prospective cohort of 62 patients.

PURPOSE: The results of a prospective series of 62 patients treated for neuromuscular spinal deformities with spinopelvic fixation using iliosacral screws are presented and discussed. METHODS: Sixty-two consecutive patients diagnosed with neuromuscular disorders were prospectively included. Pelvic obliquity and other angular parameters were measured. RESULTS: Mean age was 15.2 years (11.9 to 19.2 years). Spinal deformity was a thoracolumbar curve in 36 cases, a lumbosacral curve in 14 cases, a lumbar curve in four cases, and a combined thoracic and lumbar curve in eight cases. Lumbo-pelvic correction was done using two different strategies. In 15 patients with a normal frontal spinopelvic balance, the two rods were extended directly down to the iliosacral screws. In 47 patients with pelvic obliquity, iliosacral screws were linked to two short rods. The correction was then corrected by distraction and contraction maneuvers applied between the long and short rods. Postoperative angular parameters showed a good correction of spinal deformity in both groups. Patients with preoperative pelvic obliquity had a satisfactory and stable correction at final follow-up. CONCLUSIONS: The technique of pelvic fixation using iliosacral screws and connectors reduce difficulties and operative time due to the complicated three-dimensional bending of the rods for proper placement within the ilium. In patients with preoperative pelvic imbalance, a powerful pelvic anchorage as the iliosacral fixation allowed to use intraoperative reduction maneuvers. Despite the high rate of infectious complications in our patients, we think that our technique provided effective and improved spinal correction for patients with neuromuscular scoliosis.