From 1986 to 1990, 42 feet in 30 patients had a combined chevron osteotomy and lateral release to correct their painful bunion deformity. Seventeen patients, 23 feet, were available for follow-up. The purpose of this study was to evaluate the outcome of this procedure and to determine the incidence of avascular necrosis. The patients were examined by an independent examiner, radiographs obtained, and questionnaires filled out. Avascular necrosis was determined using plain films read by a musculoskeletal radiologist who did not know the outcomes. The average age was 45 years at the time of the procedure. Average follow-up was 50 months. The preoperative intermetatarsal angle averaged 13 degrees and the hallux valgus angle averaged 31 degrees. At study follow-up, the intermetatarsal angle averaged 8 degrees and the hallux valgus angle averaged 17.5 degrees. The results were graded by the Mayo Clinic Forefoot Scoring System (75-point scale) and a subjective scoring system. Average postoperative Mayo Clinic score was 67. Fifteen feet were subjectively rated as excellent, six as good, and two as fair. Complications occurred in four feet. Hallux varus occurred in two feet, extension contracture in one foot, and an infection in one foot. None of the feet developed definite radiographic evidence of avascular necrosis. Distal chevron osteotomy combined with a lateral release for corrective bunion surgery has come under scrutiny, because of the risk of avascular necrosis of the first metatarsal head. However, our study showed no evidence of avascular necrosis on radiographs. In addition, 91% of patients had good to excellent results at an average 50-month follow-up.

No abstract

The purpose of this study was to quantitate the blood flow of the anterior cruciate ligament in vivo. Functional flow was evaluated using laser Doppler flowmetry (LDF), for which the output signal, blood cell flux (BCF), is expressed in terms of volts. Ten patients undergoing routine arthroscopic surgery with clinically intact anterior cruciate ligaments were selected at random for participation in the study. Under arthroscopic visualization, a 2.2-mm probe was placed through a trocar sleeve into the anterior cruciate ligament after the arthroscopic procedure. Pulsatile flow within the ligament was observed in all patients. The mean maximum BCF value ranged from 101 to 274 mV; SD range was +/- 3-9 mV. The mean minimum BCF ranged from 75 to 197 mV; SD range was +/- 0 to 9 mV. Laser Doppler flowmetry offers significant promise as a method for measurement of in vivo anterior cruciate and cruciate substitution blood flow.

The development of laser Doppler flowmetry (LDF) has provided a real-time, reliable method for monitoring capillary perfusion in multiple tissues. LDF has potential for the experimental and clinical assessment of bone blood flow. To compare the accuracy and ease of use of two commercially available laser Doppler flowmeters with different mechanisms for processing the Doppler-shifted component of light, estimates of bone blood flow were obtained in a sheep model using the two systems, and the values derived then compared with estimates of bone blood flow also obtained in a sheep using the technique of injection of labeled microspheres. The single-channel laser Doppler flowmeter, the LD 5000, processes the reference and Doppler-shifted beams on the surface of a single photodetector using optical heterodyning for measurement. The dual-channel flowmeter, the Periflux 2, uses two optical fibers to transmit reference and Doppler-shifted light to two separate photodetectors. The differential amplification and detection system improves the signal-to-noise ratio. Measurement of both metaphyseal (cancellous) and diaphyseal (cortical) blood flow using both LDF systems was compared with values obtained with an injection of 85Sr-labeled microspheres in three sheep. The LDF measurements were repeated after occlusion of the left femoral artery, and a 46Sc microsphere injection was performed prior to animal sacrifice. Two of the animals developed vasomotor instability, resulting in poor correlation between the measurements obtained with the Periflux 2, which is motion sensitive, and the values obtained with the microsphere method. High correlation was apparent in two of the three animals for the LD 5000 and the microsphere values.(ABSTRACT TRUNCATED AT 250 WORDS)