Larry A. Danzig

Nutrition of the anterior cruciate ligament Effects of continuous passive motion

Twelve freshly killed mature male rabbits were used to study the effects of continuous passive motion (CPM) on regional and overall nonvascular nutritional path ways of the anterior cruciate ligament (ACL). One hundred fifty microcuries of 35sulphate was injected intraarticularly into each knee joint. The right knee underwent CPM for 1 hour, while the left knee remained immobilized. Both knee joints were then isolated and immediately frozen. The ACLs were removed while still mostly frozen, and sectioned into anterior, middle, and posterior thirds for the six rabbits in Group 1, and proximal, middle, and distal thirds for the six rabbits in Group 2. In addition, quadriceps tendon samples were harvested from each limb of three rabbits. After appro priate processing, all samples were counted in a scin tillation counter, and counts per minute per milligram of tissue were calculated. There was significantly higher uptake in rest extremity ACLs compared to CPM ex tremity ACLs (P = 0.0001 ). No significant difference was demonstrated in regional uptake comparing re spective thirds of the ACL in either Group 1 or Group 2. Quadriceps tendon uptake trended higher in the limbs exposed to CPM compared to those maintained at rest (P = 0.14). The ACL uses diffusion as a primary nutrient pathway. CPM does not increase nutrient up take by the ACL in this avascular model, but CPM may facilitate transport of metabolites out of the joint. No regional differences in uptake within the ACL occurred in either group.

The Hill-Sachs lesion. An experimental study.

The Hill-Sachs lesion is an important indication of previous anterior shoulder dislocation. We created Hill-Sachs lesions by using cadaveric humeri. Roentgenographs of these cadaveric humeri in the standard projections were then taken. Under fluoroscopy, new projections of the cadaveric humeri were obtained. In a clinical study, 15 patients (14 men and 1 woman; age range, 23 to 63 years; mean, 30 years) with known recurrent anterior shoulder dislocations were evaluated by using standard and new roentgenographic projections. On the basis of the cadaveric and clinical studies, the optimal methods for detect ing Hill-Sachs lesions include the following three roentgeno grams : anteroposterior view of the glenohumeral joint with the humerus in 45° internal rotation, the notch (Stryker) view, and the modified Didiee view.

The effects of non-weight-bearing and limited motion on the tensile properties of the meniscus

Recent clinical studies have suggested that many of the complications of prolonged immobilization after knee surgery can be prevented by permitting early motion while minimizing loading of healing tissues. The purpose of this study was to determine the effects of such a regimen on the tensile properties of the meniscus. The right knee of 10 skeletally mature sheep received a sham operation after which the hindlimb was placed in a harness that prevented weight bearing while permitting limited knee motion. The left knee served as the nonoperated control. Twelve weeks after surgery, paired specimens from the medial meniscus of each limb were tested in tension with the load parallel to the circumferentially oriented collagen fibers. No significant differences in the modulus, tensile strength, and ultimate strain between treated and control medial menisci were identified. Our data thus suggest that preventing weight bearing while permitting even limited motion of the knee will prevent any detrimental effect on the tensile properties of the meniscus in the circumferential direction.

Diagnosis and treatment of diffuse pigmented villonodular synovitis of the hip.

The first account of a circumscribed articular lesion due to pigmented villonodular synovitis (PVNS) was made by Simon in 1865l’, who considered this lesion to be a sarcoma. MoserI6 in 1909 reported the first example of the diffuse form of PVNS; the ankle was affected and the patient was free of recurrence seven years after synovectomy. Dowd* in 1912, who initially described the diffuse synovial lesion of the knee, was the first to question the malignant nature of this type of lesion. I n 1941, Jaffe et al.” introduced the term pigmented villonodular synovitis. Their observations, based on clinical a n d pathological experience with 20 cases involving joints, tendon sheaths and bursae, represent the definitive account of this condition. They

Evaluation of unstable shoulders by computed tomography A preliminary study

Three patients who had various types of glenohumeral joint instability, and in whom computed tomography (CT) was utilized as an additional diagnostic modality, are presented. In two of the three patients, routine radiography supplemented with special views docu mented the presence of a Hill-Sachs lesion; in the third, an equivocal abnormality was apparent. In all three individuals, CT verified the presence of a Hill- Sachs lesion; in one patient, there was also a Bankart deformity. CT represents a new and important modal ity that may be applied to the diagnostic evaluation of patients with unstable shoulders.

Osseous landmarks of the normal knee.

Increasing utilization of various orthopedic techniques, including total knee arthroplasties2 and reconstructive ligamentous procedures ,3 requires a thorough knowledge of the normal radiographic anatomy of the knee joint. With this in mind, we undertook a comprehensive anatomic, radiographic, and pathologic study of the knee joint in order to define the basic bony landmarks which aid in the interpretation of radiographs in both normal and abnormal articulations. Particular attention was directed to landmarks on the distal femoral condyles, the proximal tibial plateaus, and about the proximal tibiofibular joint.

Coccidioidomycosis of the extensor tenosynovium of the wrist. A case report.

A 59-year-old man had isolated coccidioidomycosis infestation of the tenosynovium of the wrist extensor tendons resistent to surgical and amphotericin chemotherapy. Some improvement has been noted on Miconazole chemothearapy, but neither the long term side effects nor clinical results are known.

The treatment of cervical spine metastasis from the prostate with a Halo cast.

Three patients with adenocarcinoma of the prostate and metastasis to the cervical spine required stabilization to prevent neurologic impairment. In each instance, a Halo cast was used. This method of stabilization is easily applied and well suited for patients with shortened life expectancy. It allows protection of the cord while chemotherapy and radiation are administered.