[A swelling in the knee cavity, not caused by a Baker's cyst but by a nerve sheath tumour]. / Een zwelling in de knieholte, niet veroorzaakt door een baker-cyste, maar door een zenuwschedetumor.

In a woman, aged 30 years, who presented with a right popliteal mass, a Baker's cyst (popliteal cyst) was diagnosed. Five years later she developed symptoms that were attributed to compression of the peroneal nerve by the mass. Because of the troublesome nature of these symptoms, it was decided to excise the mass. Immediately after the operation, a complete loss offunction ofthe common peroneal nerve was apparent. Histopathologic examination revealed an ancient schwannoma (nerve sheath tumour). The most important reason for not having diagnosed the schwannoma was that it was not considered in the differential diagnosis of the popliteal mass. Although Baker's cysts are the most common popliteal masses, nerve sheath tumours should also be considered in the differential diagnosis.

[Medial unicompartmental knee prosthesis for patients with unicompartmental gonarthrosis]. / Mediale unicompartimentele knieprothese voor patiënten met unicompartimentele gonartrose.

The function and survival time of unicompartmental knee prostheses for patients with severe gonarthrosis have been improved the past few years by developments in their design, the instrumentarium and the surgical technique. A medial unicompartmental knee prosthesis may be indicated in patients with arthrosis of the medial tibiofemoral compartment. The prerequisites are an intact anterior cruciate ligament, an intact lateral compartment, a correctable varus axis and sufficient flexion in the knee. Contraindications are inflammatory arthropathies and a recent episode of septic arthritis. Relative contraindications are: old age, excess body weight, patellofemoral arthrosis and chondrocalcinosis. A unicompartmental knee prosthesis can be placed via a small parapatellar incision. The postoperative recovery is more rapid than following the classical open approach, while the knee function after 5 years is comparable. The knee function also seems better following a medial unicompartmental knee prosthesis than after valgusising tibial head osteotomy. The latter is still preferred for young active patients. Medial unicompartmental knee prostheses fail in 6-8% of patients. Revision to a total knee prosthesis is then the treatment of choice. In the long term, unicompartmental prostheses with a mobile bearing become loose less often than comparable prostheses with a fixed bearing.

Aberdeen Colles' fracture brace as a treatment for Colles' fracture. A multicentre, prospective, randomised, controlled trial.

We carried out a randomised, prospective, multicentre clinical trial of the treatment of Colles' fractures. A total of 339 patients was placed into two groups, those with minimally displaced fractures not requiring manipulation (151 patients) and those with displaced fractures which needed manipulation (188 patients). Treatment was by either a conventional Colles' plaster cast (a control group) or with a prefabricated functional brace (the Aberdeen Colles' fracture brace). Similar results were obtained in both groups with regard to the reduction and to pain scores but the brace provided better grip strength in the early stages of treatment. This was statistically significant after five weeks for both manipulated and non-manipulated fractures. At the tenth day the results were statistically significant only in manipulated fractures. There was no significant difference in the functional outcome between the two treatment groups. However, younger patients and those with less initial displacement had better functional results.

Use of the Swanson silicone trapezium implant for treatment of primary osteoarthritis : long-term results.

BACKGROUND: Instability of the prosthesis and silicone-induced synovitis have led most surgeons to abandon use of the Swanson trapezium implant for the treatment of primary osteoarthritis. However, the literature contains little information on the results of long-term follow-up. The present study was conducted to establish the long-term results and to highlight the problems associated with the implant. METHODS: Thirty-five patients (forty-five implants) of our initial forty-five patients (fifty-seven implants) were available for clinical review. The mean duration of follow-up was 13.8 years. The objective result was assessed with a 40-point clinical scoring system. The subjective result was measured with a visual analog scale. A clinical score of 30 to 40 points and a subjective score of 8, 9, or 10 points were considered a good-to-excellent result. Radiographs were evaluated to determine the position and deformation of the prosthesis and to check for osteolytic changes of the bone, indicating silicone-induced synovitis. RESULTS: The overall clinical and subjective results were good for twenty-seven thumbs (60%). Eighteen thumbs (40%) had a dislocation, and nine of them had a revision. Three more revisions were carried out because of silicone-induced synovitis, persistent pain after reflex sympathetic dystrophy, and deep infection in one thumb each. Revision surgery consisted of resection of the implant, with or without tendon interposition, or implantation of a new prosthesis. Of the thirty-two prostheses (thirty that had not been revised and two that had been revised) for which follow-up radiographs were available, six (19%) showed wear and deformation and five (16%) also were associated with osteolytic changes. CONCLUSIONS: The main problem associated with the prosthesis was dislocation. Surgical measures to improve stability did not prevent this complication. The results after revision because of dislocation were no better than those associated with unrevised dislocated implants. In addition to dislocation, radiographic signs of silicone-induced synovitis were frequently noted, although they did not necessarily lead to a poor result. We concluded that the results after long-term follow-up of the Swanson silicone trapezium implant for the treatment of primary osteoarthritis were poor and that our decision to stop using this implant in 1991 was correct.

The Stanmore total hip replacement. A 22-year follow-up.

From a series of 135 patients (146 prostheses) who had had primary hip replacement in 1975 and 1976 we reported the outcome at ten years in 83 surviving patients in 1988 and that at 15 years in 44 surviving patients in 1994. Now, 22 years after the operation, we have reviewed the 21 patients who are still alive. Nineteen (20 hips) of these 21 patients (22 hips) with a mean age of 85.7 years still had their original prosthesis. Most patients were satisfied with the result, although the level of activity in many was reduced because of increasing age and other medical problems. The stem was stable in all 20 hips. Only one cup was definitely loose. Wear was observed in 40% of the cups but this was not a clinical problem. At the 22-year follow-up the cumulative survival rate of the prosthesis was 85%, of the stem 91% and of the cup 88%. Since 1975, 11 (7.5%) of the original 146 prostheses have been revised.

Repeat chemonucleolysis is safe and effective.

A review was made of 85 patients who received a second injection of chymopapain because of a recurrent disc herniation between 1980 and 1996. All patients were pretreated for 3 days with H1 and H2 receptor blockers. Immediate sensitivity reactions were not seen. Four Type 1 and one Type 2 reactions were seen after the the second injection. No other complications were seen. In this group of 85 patients, 66 patients received a second injection at the same level as primary treatment after a period of 57.1 months (range, 2-143 months). Two patients were lost to followup. Four patients had surgery, three with good results. Good results and no complications were seen in three patients who had a third chemonucleolysis because of another recurrence after 15, 40, and 56 months, respectively. The remaining 57 patients were interviewed after 64 months (range, 3-143 months). Using the Prolo scale, 51 patients were rated as having excellent or good results, and six patients were rated as having fair or poor results.

[Rupture of the quadriceps tendon; cannot be missed?]. / Ruptuur van de quadricepspees; niet te missen?

In four patients, two men aged 59 and 68 years and two women aged 59 and 50 years, a unilateral rupture of the quadriceps tendon was diagnosed. In two patients the disease was initially misdiagnosed. A depression was palpable in all patients just on the proximal side of the patella. All patients were treated operatively and all recovered with satisfactory knee function. In order to obtain full recovery early aetiological diagnosis is important; quadriceps tendon rupture should be considered in patients with haemarthrosis and inability to stretch the knee.

Spondylolisthesis with sciatica. Magnetic resonance findings and chemonucleolysis.

Fifteen patients with bilateral lumbar isthmic spondylolisthesis and unilateral sciatica were examined with magnetic resonance imaging. All patients had a disc protrusion at the level of the spondylolisthesis. Nine patients had a central herniated disc that caused dural sac deformation; in 6 of these patients there was extension to the disc tissue into the foramen. In 5 patients there was no clear dural sac deformation, but there was a foraminal disc protrusion that caused nerve root compression. In 1 patient there was a hernia lateral to the foramen. In none of the patients was there evidence of compression by bony elements. No abnormalities on adjacent levels were found. All 15 patients were treated with chemonucleolysis. There were no complications. A followup study was done after 19 months (range, 10-42 months). The result was rated as good or excellent in 10 of 12 patients with a spondylolisthesis of L5 and in 1 of 3 patients with a spondylolisthesis of L4. Magnetic resonance imaging showed a decrease in dural sac deformation in 4 patients, no clear decrease in 3, and a slight increase in 2. There were no distinct foraminal changes in 9 of 11 patients.

Isthmic lumbar spondylolisthesis with sciatica: the role of the disc.

Thirty-one patients with isthmic spondylolisthesis were investigated using MR imaging. Twenty-one of these patients had selectively unilateral sciatica and no abnormalities on adjacent discs. In 18 patients there was a clear correlation between the degree of foraminal stenosis and the symptomatic side. In 20 patients there was evidence of root compression by disc tissue.

Stanmore total hip replacement. A 15- to 16-year clinical and radiographic follow-up.

In 1988 we reported a ten-year review of 83 surviving patients from a group of 135 (146 prostheses) who had undergone primary hip replacement using the Stanmore prosthesis. We have now reviewed 44 of these patients at 15 to 16 years. Four patients had undergone revision, but the other 40 were all satisfied with the result of their hip replacement, 36 having little or no pain. Functional activities had decreased, but were still adequate for their average age of 81 years. There had been definite migration of the cup and/or femoral component in three hips, wear of the cup in ten and resorption of the calcar in six. Of the 24 hips inserted with radiopaque cement, eight showed an increase in radiolucent lines at the acetabular interface. The cumulative survival rate of the prosthesis was 91% at 15 to 16 years.

Chemonucleolysis in the herniated L3-L4 disk.

In a continuous series of 770 patients with a herniated disk treated by chemonucleolysis, 16 patients had herniation of the L3-L4 disk (2.1%). There were no complications, and none of these 16 patients had open surgery after the initial treatment. A follow-up study was performed after 39 months (range, six to 80 months) in 15 patients. Three patients were for the most part satisfied and 12 patients were fully satisfied with the result of treatment. Residual pain was minor in most patients. Roentgenographic signs of increased disk degeneration were seen in six patients, and reexpansion of the disk to some degree was noted in four patients. Chemonucleolysis is effective for treatment of the herniated L3-L4 disk.

[Impingement syndrome of the shoulder in patients younger than 40 years, treated with partial acromion resection]. / Passagesyndroom van de schouder bij patiënten jonger dan 40 jaar, behandeld met een partiële acromionresectie.

A retrospective analysis is reported of the results of partial acromioplasty of 22 shoulders in 19 patients with impingement problems. The population is younger than 40 years (mean 31). Four patients did not improve (18%). One (5%) showed a poor result and 14 patients (17 shoulders) (77%) had good or excellent results. The mean follow-up period was almost 3 years.

Stanmore total hip replacement. A nine- to ten-year follow-up.

Between February 1975 and August 1976, 195 total hip replacements using Stanmore components were performed; of these, 146 were in 135 patients who had not had previous hip surgery. At review 52 had died, but none of the others was lost to follow-up. Of the 52, two had had a second operation, one for infection and one for recurrent dislocation. In the remaining 83 patients (92 hips) five revisions were necessary: four for aseptic loosening, and one for stem fracture. The remaining 78 patients had little or no pain and little restriction of activity. After a follow-up period of at least nine years, the survival rate of the prosthesis was 95%. There had been migration of the femoral component in five cases and migration of the acetabular cup in one case, but no wear of the acetabular component could be demonstrated.

Computed tomography (CT) analysis of the effects of chemonucleolysis.

Computed tomography (CT) was performed on 30 patients with herniated lumbar discs before chemonucleolysis and at three and 12 months postinjection. At three months the compression produced by the herniated disc was reduced in 20 of the 30 patients; at 12 months there was complete relief of compression in all but four patients. Twenty-four patients developed diffuse bulging of the annulus. There was good correlation between the clinical results at three months and the reduction in compression as shown by the CT scan. At 12 months, no correlation was found between the remaining focal abnormalities and the clinical result. None of the patients developed epidural fibrosis. Chemonucleolysis has thus been shown to be an effective treatment of herniated lumbar discs, but it is definitely not indicated in cases where compression of the nerve root or dural sac is due to a bulging annulus.