About one-third of human breast cancers require hormones for their continued growth and endocrine ablation or anti-hormone therapy can cause regression of these tumours. As a consequence, ovariectomy in premenopausal women or administration of an anti-oestrogen (tamoxifen) in postmenopausal women represent major options for treatment of metastatic breast cancer. Alternatively, chronic administration of agonistic analogues of luteinizing hormone-releasing hormone (LHRH) causes regression of mammary tumours in experimental animals, and such treatment has shown promise in a small series of premenopausal women with advanced breast cancer. It has been assumed that these results were achieved by suppressing the pituitary-ovarian axis, as the treatment causes a reduction in circulating levels of gonadal steroids similar to that produced by castration. However, LHRH agonists can exert major effects on tissues other than the pituitary in animals and in the human. Such findings, coupled with reports of LHRH in human breast milk and immunohistochemical evidence for the presence of LHRH-like activity in some human breast tumours, prompted us to test whether LHRH agonists could have direct antitumour effects. We now report major direct effects of LHRH and its agonists on the growth of breast tumour cells in culture.

Breast Neoplasms↗

PubMedDate not supplied

Letter: Goats and rabbits on Round Island.

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Animals↗

PubMedDate not supplied

Intraarticular iliotibial band reconstruction for anterior cruciate ligament insufficiency.

Intraarticular reconstruction of the anterior cruciate ligament by transferring the distal aspect and insertion of the iliotibial band has been clinically successful. Our surgical technique theoretically retains normal neurovascular supply, and thus, the potential for dynamic repair exists. Thirty-five patients, 28 men and 7 women, underwent this reconstruction. The average age was 24 years, with a range from 18 to 46. There were 27 chronic and 8 acute injuries. Pathological findings included an absent anterior cruciate (14 knees), severe stretching (13), failed reconstruction or repair (4), midportion tears (3), and avulsion (1). Postoperative patients were evaluated according to the Kennedy criteria. An anterior drawer of 2+ was not observed in any patient. There were no cases of 2+ rotary instability, and no pivot shifts. The possibility of a dynamic or proprioceptive repair was assessed by electromyography. While no evidence of electrical activity was recorded on the gluteus maximus on 60 normal knee examinations, all 10 tested postoperative iliotibial band patients had electrical activity. The failed results of the series showed no evidence of activity.

Adolescent↗

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Evaluation of patella viability after disruption of the arterial circulation.

Fifty patients whose surgical approach violated the arterial geniculate circulation to the patella were evaluated to determine the subsequent effect on patella viability. Comparative postoperative radionuclide scans in 100 knees, 50 control and 50 surgical, revealed an avascular insult in only 7 knees (14%). It appears that the intratendinous circulation described by Björkström and Goldie protects the patella from an avascular insult in the presence of geniculate arterial disruption.

Adolescent↗

PubMedDate not supplied

Role of the posterior cruciate ligament in total knee arthroplasty.

Since the introduction of condylar knee designs, total knee arthroplasty has become a remarkably successful and durable procedure. Improvements in instrumentation systems, fixation, and patellar resurfacing have been widely applied and have made total knee arthroplasty a reproducible procedure. The appropriate role for the posterior cruciate ligament in total knee arthroplasty, however, continues to be debated. Proponents of both cruciate substitution and cruciate retention can point to excellent clinical and radiographic results in the literature with knee designs of both types. Recent research findings in the areas of biomechanics, histology, and gait analysis, combined with refinements in intraoperative technique, have further sharpened the focus of the posterior cruciate ligament debate.

Arthroplasty, Replacement, Knee↗

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Mobile bearings in primary knee arthroplasty.

Mobile-bearing knee arthroplasty (MBKA) has potential advantages compared with conventional fixed-bearing total knee arthroplasty (TKA). By allowing unconstrained axial rotation, MBKA can offer greater articular conformity without an increased probability of loosening due to increased axial torque. Increased articular conformity minimizes polyethylene contact stresses, thereby reducing linear wear and subsurface fatigue failure. Axial rotation of the platform also enables self-correction of tibial component malrotation. Despite these advantages, the long-term clinical results obtained with current MBKA devices are similar to those obtained with well-designed fixed-bearing TKA prostheses, with no data suggesting their superiority. The disadvantages of MBKA include bearing dislocation and breakage, soft-tissue impingement, a steep technique learning curve, and concerns about volumetric wear. Hypothetically, longer-term follow-up of MBKA results may reveal a significant difference from fixed-bearing TKA results as the fatigue failure threshold of incongruent polyethylene is exceeded.

Biomechanical Phenomena↗

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Aldosterone and sodium balance: towards an understanding of the basic mechanisms.

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Aldosterone↗

PubMedDate not supplied

Epiphyseal osteochondroma of the anterior cruciate ligament.

An 8-year-old Black boy complained of pain, swelling, and a decreased range of motion in the knee. One arthrotomy operation was reported to show a normal knee joint. Six months later, a second arthrotomy demonstrated an osteochondroma growing from the epiphysis into the anterior cruciate ligament. Epiphyseal osteochondroma should be added to the working differential diagnosis on children with effusion and decrease of knee motion.

Bone Neoplasms↗

PubMedDate not supplied

The total condylar knee prosthesis: the first 5 years.

The total condylar knee prosthesis evolved from previous experience with other prostheses at the Hospital for Special Surgery. This evolution includes patellar resurfacing. Subsequent modifications have led to the total condylar knee prosthesis II (a cruciate substituting prosthesis), and the total condylar knee prosthesis III (a TCP II with increased constraint). The surgical technique requires ligamentous balance with correction of preoperative deformity by a soft-tissue release. Subsequently a standard operation is performed. Four hundred and sixty-one knees were reviewed with a minimum of one year follow-up and a maximum of 5 years. Seventy-five per cent were osteoarthritic knees. Using the Hospital for Special Surgery Knee Rating Scale, the results were excellent in 312 knees (68%), good in 109 knees (23.5%), fair in 18 knees (4%) and poor in 22 knees (4.5%). Osteoarthritic knees (excellent or good 93.5%) did slightly better than rheumatoid knees (excellent or good 87%). Complications include 6 infections, 6 subluxations and 10 cases of component loosening. There were 15 reoperations (3%). The results approach total hip arthroplasty in quality and so far have not deteriorated with time.

Adult↗

PubMedDate not supplied

Intra-articular transfer of the iliotibial muscle-tendon unit.

The intra-articular transfer of the iliotibial muscle tendon unit is reproducible, does not require revascularization, and permits early rehabilitation. Of 62 patients followed Up from 24 to 55 months, excellent or good functional results occurred in 58 (93.6%). In vitro biomechanical analysis does not accurately assess this reconstruction, which appears to be a dynamic muscle tendon transfer.

Adult↗