Aim

To provide proof of concept in an in vivo animal model for the prevention of prosthetic joint infection prevention using electric fields along with conventional antibiotic prophylaxis.

Corresponding Author: Marti Bernaus

The aim of this study is to assess the extent of osteolysis around a TKR which would then help in effective planning of revision surgery.

Osteolysis around a TKR can be difficult to identify in plain radiographs because this typically occurs in low radiodensity cancellous bone of distal femur and proximal tibia. These can often look innocuous and benign allowing the surgeon to fall into a false sense of security.

We discuss the use of 3 dimensional CT scan in 7 cases with pre revision initially unsuspected massive osteolysis and its usefulness in planning appropriate implant and/or bone grafting technique in revision surgery.

6/7 knees had a primary cruciate retaining knee implant and the mean time to revision surgery was 11 years and 8 months

Based on our pre operative CT assessment we were able to plan and effectively undertake 3 custom built prosthesis and 4 stemmed revision implants along with the use of adjunct bone additives including allograft.

On the basis of this experience we would recommend the routine use of a 3D CT scan in preoperatively assessing a revision TKR and would caution the appearance particularly of the ‘posterior femoral bubble’ as it often belies a large osteolytic cavity.

Aim: This study investigated the causes of meniscal tears in an unselected adult population. No epidemiological study of this type has been undertaken since the advent of arthroscopy and MRI.

Method: The notes of all patients (1236 cases) who underwent arthroscopic surgery under the care of one knee surgeon working in a District General Hospital between 1992 and 1998 were scrutinised. 392 patients aged between 18–60 years, with normal X-rays, no previous knee injury, surgery, or arthritis, and arthroscopically proven meniscal tears, form the basis of this study.

Results: Sports injuries (Group 1) occurred in 32.4% patients. Non-sporting injuries (Group 2) accounted for 38.8% patients, 71.9% of which happened in normal daily activities. Half occurred on rising from squatting position. No Injury (Group 3) was identified in 28.8% of patients. Average age of sports group was 33 years, non-sporting group 41 years & no injury group 43 years. Male:Female = 4: 1.

Age v cause: In patients under 20 years of age meniscal tears occurred mainly in sports. In patients 20–29 years, 64.5% were related to sports, 25% to non-sporting activities & 10.5% no specific injury. Between 30–39 years, distribution was about equal in each group. In patients aged 40–49, & 50–59 years sports related tears dropped below 20%, whilst non-sporting and spontaneous tears rose to 45% and 35% respectively.

A detailed analysis of: i) the tears in relation to different sports, ii) the nature of non-sporting injuries, iii) the pathological types and distribution of tears, and iv) the associated intra-articular injuries will be presented.

Conclusions: Approximately two thirds of meniscal tears in the general population occurred during normal daily activities and in the absence of sporting injury. In nonsporting injuries the mechanism of the tears was often unrelated to loading in flexion. Tears occurred in the absence of definitive injuries even in early adulthood and middle years. Degenerative change may contribute to the pathological mechanism of meniscal tears at an earlier age than generally appreciated. Ascent from the squatting position is an important common mechanism of injury not generally described or emphasised.