The mechanism of metastasis.

The establishment of clinically detectable skeletal metastasis is a multifactorial process. This process can be divided into three general areas of understanding. The first is that of the intrinsic characteristics and properties of the tumor cells, which allow and facilitate their migration from the site of primary neoplasia to the distant host skeleton. Second, there are anatomic considerations of the human body, which influence the distribution of metastatic seeding. Third, there are the considerations of the host organism's biology, including the immune system, the circulatory system, and the affected host skeleton, which hinder and, at times, potentiate the ability of neoplastic cells to establish skeletal lesions.

Arthrofibrosis in acute anterior cruciate ligament reconstruction. The effect of timing of reconstruction and rehabilitation.

Arthrofibrosis is a potential complication of acute ACL reconstruction. Arthrofibrosis prevents the patient from regaining full range of motion, particularly the terminal 5 degrees of full extension, postoperatively. We did a retrospective study of 169 acute ACL reconstructions in a population of young athletes (average age, 22 years). We sought to determine the optimal time to perform acute ACL reconstruction with respect to arthrofibrosis and the effects of an accelerated versus conventional rehabilitation program. The short-term results were evaluated by range of motion measurements and 13 week Cybex scores. Patients whose ligaments were reconstructed within the 1st week after injury (Group I) had a statistically significant (P less than 0.05) increased incidence of arthrofibrosis (limited extension, scar tissue) over patients who had ACL reconstruction delayed 21 days or more (Group III). At 13 weeks after the reconstruction procedure, Group III patients scored an average of 70% (compared to 51% for Group I, P less than 0.05) on the Cybex evaluation. They also showed a trend toward more flexion of the knee as well as near full extension. Patients who had an ACL reconstruction between 8 and 21 days after injury (Group II) had a similar incidence of arthrofibrosis as Group I when they followed a conventional rehabilitation program postoperatively. However, only a small number of cases (approximately 4%) of Group II patients who followed an accelerated postoperative rehabilitation program had any arthrofibrosis--an observation we also made in the Group III patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute anterior cruciate ligament injury.

This article covers a retrospective investigation of the time from an acute anterior cruciate ligament tear to the intra-articular reconstruction of the tear. The study was conducted to find a specific time that would result in greater knee strength, range of motion (ROM) and/or patient satisfaction after surgery. The patient population was divided into three groups, and the Cybex, ROM and modified Noyes' questionnaire scores were evaluated for each group. The patient data base was collected through the Physical Therapy Department at Methodist Sports Medicine Center in Indianapolis. The analyses indicated that patients who delayed surgery for 22 or more days had better ROM scores, specifically full extension. The results did not show any correlation between the time from injury to surgery and the postoperative strength or patient satisfaction of the involved knee. Further analyses also indicated that patients who delayed surgery for one week or more and who underwent an accelerated rehabilitation program after surgery attained full range at a similar rate as those who delayed surgery for 22 or more days.