Neglected, developmental hip dislocation treated with external iliofemoral distraction, open reduction, and pelvic osteotomy.

Between 1995 and 2003, we operated upon 18 children with 20 hips involved, aged 5-11 years (average: 7.5 years) suffering from an inveterate high developmental dislocation of the hip joint. An average follow-up period of our middle-term study was 51 months (range: 34-96 months). A two-staged management was applied. First, femoral head was lowered back to the level of acetabulum with an external fixator or a distractor device. The second stage involved open reduction combined with pelvic osteotomy and, in four cases with femoral derotation osteotomy. We noted two cases of avascular necrosis. Equal limb length was achieved in 15 cases. There were two cases of 0.5-cm length discrepancy, two cases of 1-cm length inequalities, and one case of 5-cm limb shortening. We endorse this method in neglected cases of previously untreated unilateral high developmental hip dislocations in children aged 8-10 years. It results in a usable hip joint without the need of femoral shaft shortening and facilitates future joint replacement.

Ultrasound measurement of rotator cuff thickness and acromio-humeral distance in the diagnosis of subacromial impingement syndrome of the shoulder.

The usefulness of ultrasound measurements in the diagnosis of the subacromial impingement syndrome of the shoulder was evaluated. Fifty-seven patients with unilateral symptoms of the impingement syndrome underwent ultrasound examination of both shoulder joints, which included assessment of rotator cuff integrity, measurement of rotator cuff thickness and the distance between the infero-lateral edge of acromion and the apex of the greater tuberosity of humerus (AGT distance) in the standard ultrasonographic positions. As a control group, 36 volunteers (72 shoulders) with no history of shoulder pain were examined sonographically. Ultrasonographic assessment of humeral head elevation, measured as the AGT distance, proved to be useful in establishing the diagnosis of the subacromial impingement syndrome of the shoulder. A difference in rotator cuff thickness of more than 1.1 mm and a difference in the AGT distance of more than 2.1 mm between both shoulder joints may reflect dysfunction of rotator cuff muscles.

Stress distribution around a TKR implant: are lab results consistent with observational studies?

Malalignment of Total Knee Replacement prosthesis has been reported to limit the implant survival time. We hypothesized that this may be secondary to excessive stress occurring at the bone-implant interface, resulting from abnormal load transfer across the knee joint. In this study, we conducted Finite Element Analysis of a geometrical model of the knee joint after Total Knee Replacement with different axial alignments. The calculated stresses and displacements were significantly higher with varus knee malalignment than with the valgus one. The stresses are not high enough to pose a serious risk of a crack or a fracture but might be responsible for chronic pain reported by some patients. In cases where optimal implant positioning is not possible, slight valgus malalignment might produce better results than varus.