Cortical plasticity in the first year after cochlear implantation.

This study aimed to investigate changes in auditory and visual cortical activity over the first year following cochlear implantation using (18)F-fluorodeoxyglucose positron emission tomography. Subjects underwent scanning prior to the initial implant activation (control), after one to two months of implant use (early activation) and after one year of implant use (late activation). All subjects had activation of the auditory cortices. Group analysis using Statistical Parametric Mapping package SPM99 showed these became more focused over the first year of implant use. There was no evidence of left hemispheric dominance at any stage post implantation.Visual cortical activations were highly variable between patients and did not increase significantly between early and late activations. Taken together, our results lead us to suggest that the neural processes that occur during the first year of auditory rehabilitation following cochlear implantation vary between individuals to a greater extent than previously reported.

Review of 10-year results of PCA hip arthroplasty.

OBJECTIVE: To assess the long-term results of the PCA uncemented total hip replacement. DESIGN: A prospective nonrandomized clinical trial. Follow-up ranged from 8 to 11 years (mean 10.3 years). SETTING: A university hospital. PATIENTS: One hundred consecutive PCA arthroplasties were performed on 89 patients. All operations were supervised by a single surgeon. The patients' status was reviewed between September and November 1996 by an independent observer. Seventy-three total hip replacements were available for review. INTERVENTION: PCA uncemented acetabular and femoral replacement through a lateral surgical approach. MAIN OUTCOME MEASURES: The need for revision, which was classified as failure, and definite 3-zone acetabular radiolucency, which was considered radiologic evidence of loosening. RESULTS: The time to failure of the acetabulum averaged 8 years. Femoral failure occurred in 3 patients an average of 4 years postoperatively. The overall failure rate for the acetabulum was 13% and for the femur 7%. CONCLUSIONS: The acetabular failure rate is unacceptably high. Patients who have had hip replacement with the PCA prosthesis should be followed over the long term.

Restoration of metacarpophalangeal extension of the thumb in inflammatory arthritis.

Nine patients (11 cases) with inflammatory arthritis who had an early boutonnière deformity of the thumb treated by rerouting of the extensor pollicis longus tendon were reviewed. Preoperatively, all patients complained of pain, disability in activities of daily living and extensor lag of the MP joint ranging from 10 to 60 degrees. At a mean follow-up of 38 months, nine thumbs had equal active and passive MP joint extension. Two thumbs had a moderate extensor lag. Functional strength assessment demonstrated no deleterious effect of the procedure in the operated compared to the non-operated thumb. Subjectively, all patients but one were satisfied. This procedure appeared to correct or to limit the progression of the deformity. A deficit of interphalangeal extension in five patients may require a modification of the procedure to tighten the extensor pollicis longus distal to the MP joint.

Heterotopic ossification after primary cemented and noncemented total hip arthroplasty in patients with osteoarthritis and rheumatoid arthritis.

OBJECTIVE: To compare the frequency and severity of heterotopic ossification (HO) in patients with osteoarthritis or rheumatoid arthritis who undergo cemented or noncemented total hip arthroplasty. DESIGN: A prospective case study. SETTING: A university referral centre. PATIENTS: One hundred and sixty one patients underwent 184 total hip arthroplasties. The 184 hips were categorized as follows: cemented total hip arthroplasty--60 osteoarthritis hips, 26 hips affected by rheumatoid arthritis; noncemented total hip arthroplasty--67 osteoarthritic hips, 31 hips affected by rheumatoid arthritis. INTERVENTIONS: Total hip arthroplasty. A standard approach was used to implant either a cemented or noncemented prosthesis. Radiographs were obtained of each hip preoperatively, immediately postoperatively and 6 weeks, 3 months, 6 months and 1 year postoperatively. MAIN OUTCOME MEASURES: Radiographs were graded in blind fashion for HO, according to the criteria of Brooker. Modified Harris hip scores were calculated at 1 and 2 years postoperatively. RESULTS: HO (incidence of Brooker grades 2, 3 and 4) was greater after cemented (22%) than noncemented (9%) total hip arthroplasty in osteoarthritic hips (p < 0.05), but there was no significant difference between the two types of prosthesis in hips affected by rheumatoid arthritis. When both types of prosthesis were considered together there was no significant difference in the incidence of HO between osteoarthritic hips (15%) and hips affected by rheumatoid arthritis (12%). With respect to Harris hip score, the presence of grade 4 HO was associated with a significantly (p < 0.05) lower score (50.6) than grade 3 (89.4) and grade 2 (91) HO. CONCLUSIONS: Cemented total hip arthroplasty increases the frequency of HO only in osteoarthritic hips. Compared with Brooker's grades 2 and 3 HO, grade 4 HO significantly lowers the Harris hip score after total hip arthroplasty.

An unusual pattern of growth disturbance of the hip in juvenile rheumatoid arthritis.

OBJECTIVE: An unusual deformity in the hip in juvenile rheumatoid arthritis (JRA) consisting of a small femoral head in a capacious acetabulum has been described as an isolated finding, but no explanation as to the cause of the deformity has been proposed. We have also observed this deformity and the objective of this investigation was to determine the cause. METHODS: In 1987, a review of hip disease in JRA was carried out at the Wellesley Hospital. Nine hips in 5 patients were identified as having a mismatch in size between the femoral head and acetabulum. Six of these hips came to surgery during the growth phase. RESULTS: The 6 hips undergoing surgery between the ages of 16-19 showed an identical picture at the time of surgery. The pattern of pathology consisted of a femoral head devoid of articular cartilage and an acetabulum that showed an intact triradiate cartilage. Each of the 6 hips was treated with a resurfacing arthroplasty. CONCLUSION: The femoral head grows in circumference by endochondral ossification of the articular cartilage. If the rheumatoid process destroys that articular cartilage, growth of the femoral head ceases. The intact triradiate cartilage permits continuing acetabular growth and the deformity of a small femoral head in a large capacious acetabulum results.

Intertrochanteric fractures of the femur in rheumatoid arthritis patients.

In a series of 33 intertrochanteric femoral fractures in patients suffering from classic rheumatoid arthritis (RA), the typical patient was about 70 years of age, osteopenic, and severely affected by longstanding polyarticular RA of joints other than the hip. Prefracture involvement of the hip joint (other than osteopenia) was apparent radiographically in only 9.1% of patients. There was a higher rate of avascular necrosis (9.7%) and nonunion (6.5%) than expected in the nonrheumatoid general population. There was also a high rate of secondary displacement. Of three patients with avascular necrosis, two had had corticosteroid treatment.

Osteoid osteoma of the elbow: a report of six cases.

We report six cases of osteoid osteoma of the elbow. Elbow pain was the presenting complaint in all of these young adult patients. A variety of diagnoses were entertained, and four patients underwent surgical procedures that were not helpful. Although an abnormality was identified on plain x-ray films, tomograms and a bone scan were helpful in isolating the lesion. A CT scan proved valuable in two cases. Complete en bloc excision relieved pain and improved function in each case.

Listeria monocytogenes--an unusual cause of late infection in a prosthetic hip joint.

As the scope of patients having arthroplasty with compromised immune systems expands, the incidence of late prosthetic infections will increase and the variety of infecting organisms will broaden. The role of prophylactic antibiotics for such patients undergoing procedures known to cause a transient bacteremia is currently unknown. Their use is not universal and many patients undergo procedures frequently without any form of protection. The following case report outlines an unusual organism causing late hip arthroplasty infection in an immunocompromised host and examines the role of prophylactic antibiotics in preventing such complications.

Diagnosis and management of acute knee ligament injuries.

Knee ligament injuries are a common problem, especially in the athletic age group. The most common knee ligament injury is the so-called isolated anterior cruciate ligament tear. This is also the injury most likely to be missed. Isolated collateral ligament tears are generally managed non-operatively, but combined collateral and cruciate tears should be surgically repaired. "Isolated" anterior cruciate tears are generally repaired in the younger active athlete but are managed by hamstring exercises in the older individual. Isolated posterior cruciate ligament tears are managed non-operatively unless a bony avulsion is present.