Biomedical subjects

B R Tietjens

Publications and source records attributed to B R Tietjens.

4 recordsLinked to original sources

PubMed1977

A scanning electron microscopic study of wear in the plastic components of prosthetic knee and hip joints.

The polyethylene surfaces of four metal on plastic prosthetic knee joints were compared with those of four hip joint replacements, by the use of scanning electron microscopy. The acetabular components of the hip joints showed concentric machining marks, but were generally smooth, and in some areas plastic deformation of the articular surface was evident after 24 months' use. In contrast, the tibial components of knee joints removed after 12 to 22 months showed deep scoring and pitting near the centre of their articular surfaces. This appeared to be due to abrasion by a third material, possibly fragments of cement, which sometimes became embedded in the joint surface. These results indicate that wear in prosthetic knee joints may be much more rapid than in hip joint replacements made from similar materials.

Hip Joint↗

PubMed1975

Early experience with total knee replacement.

This paper presents a review of two years' experience with the geometric total knee replacement. The results of 23 arthroplasties in 22 patients are discussed. Relief of pain was consistent and dramatic, movement was increased postoperatively in only three patients, but imporvement in overall function occurred in 20 of the 22 patients. There was one failure requiring arthrodesis. In this patient, six months after surgery the medial tibial condyle collapsed and the polyethylene tibial component fractured. This complication has not been reported before. Early results are encouraging. Total knee joint replacement is a useful procedure in advanced arthritis when arthrodesis is the only alternative.

Aged↗

PubMedDate not supplied

Neglected ruptures of the patellar tendon. A case series of four patients.

We describe a series of four patients treated for chronic ruptures of the patellar tendon (more than 6 months old). The proximally retracted patella was brought back to its anatomic position, and the tendon stumps were repaired and protected with multiple strands of strong circlage wire, in a figure-of-8 pattern, from the quadriceps tendon to the tibial tubercle. Postoperatively, immediate mobilization without the use of a brace was initiated. The patients averaged 29 months (range, 8 to 80) from the time of injury until definitive treatment and were observed for an average of 27 months (range, 11 to 40) after treatment. Before treatment, all patients had an extensor lag of at least 20 degrees. At initial follow-up, all patients had full active extension with no extensor lag, and this did not deteriorate postoperatively or after wire removal. At the last follow-up, the average flexion was 0 degrees to 112 degrees. This technique avoids the use of autograft or allograft tissue and does not require lengthening of the quadriceps tendon.

Adolescent↗

PubMedDate not supplied

Long-term followup of the untreated isolated posterior cruciate ligament-deficient knee.

We evaluated 38 subjects with isolated posterior cruciate ligament-deficient knees at a mean of 13.4 years (range, 5 to 38) after injury to study the occurrence of symptoms, disabilities, and articular degeneration. Each subject completed a standardized questionnaire, physical examination, and had radiographs taken of both knees. Eight (21%) patients had surgeries for meniscal injuries after their posterior cruciate ligament injuries. The mean questionnaire score for function (50-point maximum) was 34.4 +/- 6.5 (SD) for the patients who did have meniscal surgeries versus 40.0 +/- 8.7 for the 30 patients who did not (P = 0.05). Among the 30 patients with isolated posterior cruciate ligament-deficient knees with normal menisci, 24 (81%) had at least occasional pain and 17 (56%) had at least occasional swelling. As time from injury increased, increased articular degeneration on radiographs was seen (P = 0.037). Our study suggests that the prognosis for the isolated posterior cruciate ligament-deficient knee varies. Some patients experience significant symptoms and articular deterioration, while others are essentially asymptomatic and maintain their usual knee function.

Accidental Falls↗