Thigh pain, subsidence and survival using a short cementless femoral stem with pure metaphyseal fixation at minimum 9-year follow-up.

BACKGROUND: Short femoral stems designed to spare bone stock and improve load transfer at the proximal femur level have been introduced in recent years. However, little is known on the long-term outcomes of these stems. HYPOTHESIS: Short cementless stems have low rate of thigh pain and subsidence as well as few revision needs at mid-term follow-up. MATERIALS AND METHODS: We prospectively followed 64 patients (72 hips) undergoing total hip arthroplasty with a femoral stem designed to achieve a pure metaphyseal fixation. Patients with hip fracture, femoral neck deformity and osteoporotic bone were excluded. Clinical evaluations were performed annually until the last follow-up, a minimum of 9 years after surgery. At each follow-up, implant positioning was assessed on conventional plain films with a computer assisted radiographic evaluation. RESULTS: The Harris hip score improved from 43 points (range 19-50) before surgery to 88 points (range 73-100) at the final follow-up (P=0.001), and the Womac score averaged 47 points (range 35-56 points) preoperatively and 76 points (range 63-84) at the last follow-up (P=0.001). Thigh pain was reported by five patients (8%) at the 2-year follow-up, but only in two (3%) was still present, and related to the prosthesis, at last follow-up. Computer assisted radiographic analysis showed a neutral alignment of the stem in 56% of cases, a varus-valgus alignment less than 5° in 36% and equal to 5° in 8%. Stem subsidence was observed in 12 hips but was less than 4mm in all cases (range 0-3mm). Calcar height remained unchanged over time. Adaptive bone remodelling, including proximal bone resorption and distal cortical hypertrophy were not observed at follow-up. No patients had aseptic loosening of the stem nor were radiolucent lines detectable at the level of the porous coating. Survivorship analysis showed a 100% survival rate of the stem at nine years. DISCUSSION: This study showed that a femoral stem designed to achieve a pure metaphyseal fixation may obtain, in a selected group of patients with adequate bone quality, satisfactory clinical outcomes without compromising implant stability. The limited periprosthetic bone remodelling observed after a minimum of 9 years follow-up suggests that this type of implant may improve mechanical stresses on host bone compared with standard stems requiring diaphyseal fixation. LEVEL OF EVIDENCE: Level IV. Historical series.

Pathophysiology of gastroesophageal reflux and distal esophageal motility in children with gastroesophageal reflux disease.

We investigated the mechanisms of gastroesophageal reflux (GER) and esophageal motility during endogenous esophageal acid exposure in 17 patients with reflux disease alone (age range 3-20 months) (group A) and in 10 patients with reflux disease complicated by esophagitis (age range 4-19 months) (group B), by simultaneous recording distal esophageal sphincter relaxation was the predominant mechanism of reflux in both groups of subjects; however, it was more frequent in group B patients (Bpts), whereas reflux episodes due to appropriate sphincter relaxation were detected more frequently in group A patients (Apts). During endogenous acid exposure, primary peristalsis was the most frequent esophageal motor event in all patients; furthermore, its amplitude was significantly higher in Apts as compared with Bpts. Primary peristalsis was more efficacious (rise of intraluminal pH by at least 0.5 unit) in patients with reflux disease alone, whereas nonspecific motor irregularities were more common in children with reflux esophagitis. It is concluded that the major mechanism of GER in patients with reflux esophagitis is an inappropriate sphincter relaxation; reflux due to appropriate sphincter relaxation is associated with less severe reflux disease; and patients with esophagitis exhibit a deranged esophageal motility during spontaneous acid exposure.

[Kinetics of tetanus antitoxin after administration of specific immunoglobulins]. / Cinetica dell'antitossina tetanica dopo somministrazione di immunoglobuline specifiche.

The antitoxin titer, at different time intervals from the administration of 250 I.U. of specific immunoglobulins, was determined by means of passive hemagglutination in the serum of 28 non-immune subjects, selected among the wounded hospitalized at a First Aid Station. The maximum titer of circulating antitoxin was reached in the majority of the cases, already after 6 hours. Twenty-four hours after the inoculation, 62.5% of the treated subjects showed antibodies with a titer equal to, or higher than, 0.01 I.U./ml. Nine of the subjects, who showed antibodies, were monitored for 30 days. The level of tetanus antitoxin was not appreciably modified within the first 10 days. Between 11 and 20 days the titer, even though reduced on the average, remained above the minimum protective level of 0.01 I.U./ml, while after 21-30 days, this titer dropped under this value in three out of 6 subjects.