Biomedical subjects

G E van Dyk

Publications and source records attributed to G E van Dyk.

4 recordsLinked to original sources

PubMed1998

Cancellous bone grafting of large osteochondral defects: an experimental study in dogs.

Autogenous cancellous bone was evaluated as a material to repair large osteochondral defects in 20 adult mongrel dogs. In one knee, the bone graft was used to fill an osteochondral cylindrical defect (10 mm diameter x 10 mm deep) created in the femoral trochlea. A similar lesion was created in the contralateral knee but was left untreated for spontaneous healing. Four animals were killed at each of five periods (2, 4, 8, 12, and 24 weeks), and the healing response of the defects was evaluated by gross anatomic inspection, plain film radiography, high-resolution radiography, and histology. The results of this study suggest that the use of a cancellous bone graft accelerates the repair of large osteochondral defects and produces more uniform filling of the defect than the ungrafted control. The reparative surface of the grafted lesions also differed from that of controls, having uniform coverage with histochemical-positive staining fibrocartilage at 8 weeks, a finding not observed in any control defect through the length of this study, 24 weeks.

Animals↗

PubMed1997

The popliteal bursa (Baker's cyst): an arthroscopic perspective and the epidemiology.

The purpose of this study was to establish the incidence of the anatomic structure, the popliteal bursa, in patients undergoing arthroscopy and to determine the relationship to associated clinical and pathological factors. Diagnostic arthroscopy was used to identify the presence of the popliteal bursa in 187 consecutive patients (195 knees). Thirty-seven percent of knees had a popliteal bursa identified by the communication with the posterior medial compartment. The cause of the popliteal bursa was not established by this study. This study refuted the causes proposed by others. The existing erroneous conclusions concerning the cause of the popliteal bursa were probably attributable to the failure to recognize the common continuity of the bursa and the knee joint. When the popliteal bursa is present (37%), it becomes symptomatic by responding to the intraarticular disease because of its continuity with the knee joint.

Adult↗

PubMedDate not supplied

Clinical assessment of asymptomatic knees: comparison of men and women.

Two hundred ten adults, 100 women and 110 men, were recruited on the condition of always having asymptomatic knee joints. These recruits were initially solicited by newspaper advertisement. The women were recruited in 3 weeks, but additional efforts and 3 months were necessary to assemble the group of men. The volunteers underwent a uniform comprehensive medical history questionnaire, physical examination, and plain film radiographs. The data collected were subjected to computerization and statistical analysis. Although these subjects were always asymptomatic, only 4.5% of 200 women's knees and 21% of 220 men's knees had no "positive" physical findings. The findings of hypermobile patella, patellar crepitus, and lateral patellar position on Merchant x-ray view were common. Findings not present or infrequent in these asymptomatic subjects and potentially pathological were patellar J-sign, decreased range of motion, asymmetrical ligamentous laxity, McMurray's sign, compartmental crepitus, and severe degenerative arthritis or loose bodies on radiograph. The findings in women were different from those observed in men. This gender-specific information should be helpful in patient management but also useful and timely for establishing practice guidelines, treatment algorithms, and outcome study instruments.

Adolescent↗

PubMedDate not supplied

Endoscopic calcaneoplasty.

Endoscopic calcaneoplasty offers access to the retrocalcaneal space, thereby making it possible to remove inflamed retrocalcaneal bursa as well as the posterosuperior part of the calcaneus in applicable cases of painful hindfoot. In this study, endoscopic calcaneoplasty was performed in 21 procedures in 20 patients. All of the patients had typical complaints of inflammation of the retrocalcaneal bursa that were unresponsive to nonoperative treatment for more than 6 months. In all patients a superior calcaneal angle of more than 75 degrees and positive parallel pitch lines were present on the lateral calcaneal radiograph. The mean follow-up was 3.9 years (range, 2 to 6.5). There were no surgical complications and no postoperative infections. One patient had a fair result, 4 patients had good results, and the remaining 15 patients had excellent results. Whether this operation is performed by endoscopic or open technique, enough bone must be removed to prevent impingement of the bursa between the calcaneus and Achilles tendon. Endoscopic calcaneoplasty is a minimally invasive technique performed in an outpatient setting and combined with a functional rehabilitation program. The procedure has low morbidity. Patients have a short recovery time and quickly resume work and sports.

Adolescent↗