Gudmund Blomgren

Factors Associated with Heterotopic Bone Formation in Cemented Total Hip Prostheses

A series of 237 total hip replacements were analysed by means of a computer program. High body weight and postoperative fever, as well as several indications of a technically demanding operation, occurred significantly more often in the group of patients which developed paraarticular ossification postoperatively. The results point to a causal relation between tissue trauma and heterotopic bone formation. We wish to underline the importance of a gentle handling of tissues in the performance of a total hip replacement if the rate of ectopic bone is to be reduced to a minimum.

Hematogenous infection after knee arthroplasty

Twenty-five hematogenously infected knee arthroplasties in 20 patients (17 with rheumatoid arthritis and 3 with arthrosis) were followed for 3 years. Staphylococcus aureus was the major infecting organism. Three patients with four arthroplasties died of sepsis. Two patients had removal of the arthroplasty, one of which resulted in an above-the-knee amputation. Four out of five arthrodeses fused. Two knees healed after early debridement and two healed without surgery. Ten knees had successful revision arthroplasty. Rheumatoid arthritis and constrained prostheses increase the risk of hematogenous infection. Any infection and especially cutaneous lesions in a patient with a knee arthroplasty should be treated vigorously.

Integrity of the gluteus medius after the transgluteal approach in total hip arthroplasty

The postoperative integrity of the conjoined aponeurosis of the gluteus medius and vastus lateralis was studied in 97 consecutive total hip arthroplasties in 95 patients performed via a transgluteal approach. Metal markers were placed in the gluteal/vastus aponeurosis, one on each side of the suture line, and the integrity of the repair was assessed on radiographs taken immediately after surgery and 2 weeks, 2 months, and 1 year after operation. Separation between the markers occurred in about half of the patients, but gross separations were rare. Since most separations showed a progressive increment, elongation of the sutured aponeurosis might be a more common mechanism than perioperative injury to the neurovascular pedicle. Moreover, the degree of separation did not correlate with pain, and Trendelenburg gait was significantly increased only in the group of patients with a separation greater than 2.5 cm, indicating that a moderate gluteal elongation may be readily compensated for.

Late hematogenous infection in total joint replacement: studies of gentamicin and bone cement in the rabbit.

Hematogenous infection of total joint replacements was experimentally produced in rabbits with cemented endoprostheses in both knees. One one side the bone cement contained gentamicin. Bacteremia was induced six to eight weeks postoperatively using a strain of Staphylococcus aureus. Twenty-five days after the induction of bacteremia approximately a third of the artificial joints were infected, whereas no bacteria were found in blood and viscera. Although the gentamicin cement still possessed anti-bacterial activity in vitro, it did not prevent hematogenous infection. Thus, gentamicin cement would not protect the joint against delayed hematogenous infection.

Late results of the Souter-Strathclyde total elbow prosthesis in rheumatoid arthritis 6/19 implants loose after 5 years

We performed total elbow replacement, using the Souter-Strathclyde prosthesis in 19 elbows of 18 patients with rheumatoid arthritis and followed the patients for 5 (1-11) years. Pain relief was achieved initially in all patients. The average range of flexion-extension was increased by 12 degrees and pronation-supination by 40 degrees. There were no infections. 1 patient sustained an intraoperative fracture of the medial epicondyle, 3 patients developed neuropathies and 1 patient had an immediate postoperative dislocation of the joint. At follow-up, 6 prostheses had radiographic loosening, with sagittal titling and migration of 4 humeral components. 2 patients had clinical symptoms of loosening.

Low-vs high-viscosity cement in hip arthroplasty: No radiographic difference in 226 arthrosis cases followed for 5 years

In 1984 and 1985, 352 hips were randomly assigned to total hip arthroplasty with either low- or high-viscosity cement at 5 Swedish orthopedic departments. Of the 267 hips finally included in the study, 226 were examined clinically and radiographically after 54-77 months. Radiographically, 21 definite stem loosenings and 1 probable stem loosening were observed (10 percent) and 4 additional stems had been exchanged before the 5-year examination. In the survivorship analysis, 261 stem prostheses were included and using this method, 7 percent were radiographically loose after 5 years. There were 4 definitely loose and 8 probably loose acetabular cups. No difference was found between cement of high and low viscosity with regard to prosthetic fixation.

Factors Associated with Early Loosening of Cemented Total Hip Prostheses

Patient data and radiograms from a series of 237 consecutive total hip replacements were evaluated by means of a computer programme in an attempt to study factors correlated with early loosening. We found that the loosening rate was significantly influenced by several factors. The CAD-prosthesis (Computer Assisted Design, Howmedica) was found to be superior to the Charnley-Müller-prosthesis. The viscosity of the cement seemed to be an important factor in that low viscosity was positively correlated to loosening whereas high viscosity showed a negative correlation. Several technical details in the performance of the operations as well as loosening correlated with the surgeon. Males who preoperatively had fairly unrestricted physical activity and high body weight were more prone to early loosening. No correlation was found with the diagnosis, previous hip surgery, age, osteoporosis or cortisone treatment preoperatively. We wish to underline the importance of a thorough technique and suggest that total hip replacement should be performed by specialized surgeons.

The influence of the total body exhaust suit on air and wound contamination in elective hipoperations

An evaluation of the effect of total body exhaust clothing on air and wound contamination was made in an operating theatre with a zonal ventilation system. Sixty-four patients who underwent total hip replacement using the Charnley-Müller prosthesis were studied. The members of the surgical team wore total body exhaust suits (TBE-suit), or conventional theatre clothing (C-clothing) at alternate operations. Nearly half of the patients in each group were given prophylactic antibiotics. Both the mean and median values of airborne bacteria in the operating theatre were significantly lower during operations with TBE-suits than with conventional theatre clothing. The lowest number, 4.0 cfu/m3, was found at the site of the operation wound. Cultures from adhesive drapes showed growth in 46 per cent of the C-group and in 43 per cent of the TBE-group samples. Wound washouts showed growth in 43 per cent of the C-group and in 10 per cent of the TBE-group samples. Staphylococcus epidermidis was the most frequently isolated bacteria both from adhesive drapes and from wound washouts. The rate of superficial infections was slightly higher when C-clothing was used. Deep infections were found in one patient in the TBE-group and in two patients in the C-group. None of the infected patients had received prophylactic antibiotics.

Short-term ibuprofen to prevent ossification after hip arthroplasty:No effects in a prospective randomized study of 47 arthrosis cases

Heterotopic ossification after hip arthroplasty can be prevented by ibuprofen given 3 months postoperatively. To evaluate the effectiveness of 10 days of ibuprofen treatment we performed a randomized, double-blind, prospective study on 57 patients with primary arthrosis, undergoing total hip arthroplasty. 47 patients completed the study and no effect on the incidence of ossification could be detected.

The susceptibility of total joint replacement to hematogenous infection in the early postoperative period: an experimental study in the rabbit.

Postoperatively a suspension of Staphylococcus aureus was injected intravenously in rabbits with experimental total knee arthroplasties. Four weeks after the operation 70% of the total joint replacements were infected whereas a bacterial survey revealed ony occasional positive cultures from the kidneys. The infected joint prostheses were all loose, and histologic and microradiographic signs of loosening and infection were common in the surrounding tissues. The results illustrate the importance of preventing bacteremia in the early postoperative period of total joint arthroplasty.