Supracostal approach in percutaneous nephrolithotomy: experience with 102 cases.

PURPOSE: To assess retrospectively the safety and efficacy of the supracostal approach in percutaneous nephrolithotomy (PCNL). PATIENTS AND METHODS: Among 862 patients who underwent PCNL between April 1986 and December 1999, supracostal puncture was performed in 102. Their stones were either solitary (66.5%), multiple (15.7%), or staghorn (19.6%). Upper ureteral calculi were the commonest indication (32.4%). The interspace between the 11th and 12th ribs was used in all cases. After tract dilatation with telescopic metal dilators, pneumatic or ultrasound lithotripsy was used for fragmentation. RESULTS: Complete clearance was achieved in 79.5%. Ten patients (9.8%) had pleural violation in the form of hydrothorax, pneumothorax, or hydropneumothorax. All of these patients were managed successfully by intercostal chest tube drainage. CONCLUSION: Supracostal puncture in a safe and effective approach with acceptable morbidity in selected cases of staghorn, upper ureteral, and upper caliceal calculi.

Prosthetic interposition arthroplasty for the palliative treatment of end-stage spastic hip disease in nonambulatory patients with cerebral palsy.

We reviewed our experience in using a prosthetic arthroplasty for the treatment of painful degenerative arthritis in 11 nonambulatory patients (14 hips) with cerebral palsy. Age of the patients ranged from 11 to 20 years. Three patients had previously undergone a salvage procedure. Radiographic follow-up averaged 16 months (range, 4 months to 5 years). Ten of the hips remained located on the latest radiographs, and four of the hips dislocated within 4 months of the procedure. No patient exhibited migration or failure of the implants, although one patient exhibited periprosthetic osteolysis, which remained unchanged over a 4-year period. Clinical follow-up averaged 5 years (range, 2-6 years). Ten patients (13 hips) had complete relief of hip pain. Caretaker satisfaction was high for these patients, with all 10 caretakers stating that they would recommend the procedure. One patient continued to have persistent pain in the hip, and the caretaker stated that she would not recommend the procedure.

Biomechanical and computer analysis of radial head prostheses.

Radial head fractures can lead to significant upper extremity disability. A comminuted radial head fracture with a medial collateral ligament tear presents a clinical conundrum. The radiocapitellar (RC) joint should be maintained, yet the head frequently cannot be reduced and stabilized. The silicone rubber implant currently available is not biomechanically or clinically satisfactory, and thus there is a need for a more suitable prosthetic replacement for the radial head. We have attempted to design such a prosthesis and have examined prosthetic design with various materials that would best transmit force of the RC joint. Design configurations based on our cadaveric and radiographic measurements were tested with structural finite element method computer analyses. Materials examined included titanium alloy, cobalt-chrome alloy, alumina ceramic, and ultrahigh molecular weight polyethylene (UHMWPE). Metals and ceramic transmitted force at the distal bone and implant interface and strain shielded the proximal radial cortex while UHMWPE distributed load uniformly through the cortex and along the entire bone and implant interface. In addition, load transmission comparisons were made with the intact radial head, with a silicone prosthesis, and with 6 and 10 mm thick UHMWPE prostheses in cadaveric specimens. UHMWPE prostheses transmit more force to the RC joint than the silicone prosthesis and with leads closer to physiologic levels at all flexion angles. UHMWPE prostheses not only transmit much more force than silicone, but because of substantially less deformation under load, also provide more stability to the joint.