The importance of early diagnosis in the management of proximal tibiofibular dislocation: a 9- and 5-year follow-up of a bilateral case.

Unilateral fibula head dislocation is an uncommon injury. Ogden in 1974 reviewed the literature and detected 108 cases [J. Bone Joint Surg. 56(A) (1974) 145-154]. There since have been few reported cases. Bilateral fibula head dislocation only has been reported once [Rheumatol. Int. 5(1) (1984) 45-47]. We report a patient who had developed bilateral fibula head dislocations, each side independently over a 5-year period. We emphasise the rarity of the injury, the necessity of prompt recognition and reduction, and the uncertainty for best management of this injury.

Ultrasound assessment of the efficacy of wound drains.

We report the use of ultrasound in the assessment of the efficacy of wound drains in preventing wound haematoma. 171 patients with proximal femoral fractures who underwent AO dynamic hip screw or hemiarthroplasty were randomized as to whether or not they should receive wound drainage. Patients then underwent ultrasound examination on the 5th postoperative day to localize and quantify any wound haematomas. Results show that drains are effective in preventing wound collections, but only while in situ; following the removal of drains the size of resulting wound collections is the same whether the wound has been drained or not (Student's t-test; t = 0.19, NS). This study questions current theories on the mechanisms by which wound drainage is thought to influence wound healing.

The prevalence of disc degeneration associated with neural arch defects of the lumbar spine assessed by magnetic resonance imaging.

The morphology of the intervertebral discs in 40 patients with spondylolytic and mild spondylolisthetic defects of the lumbar spine were assessed using magnetic resonance imaging. The results were compared with an age- and sex-matched asymptomatic population, and the difference in prevalence of disc degeneration between the two groups was noted. Under the age of 25 years, degeneration was uncommon in both the disc associated with the neural arch defect and the comparable disc in the control population. However, after this age, the prevalence of the disc degeneration rose in both groups, but was more marked in the spondylytic group, and this difference was statistically significant (P = 0.025). The results suggest that a neural arch defect is associated with an increased prevalence of disc degeneration, which is greater than is seen in a normal aging population.

The geometry of the muscles of the lumbar spine determined by magnetic resonance imaging.

Magnetic Resonance Imaging (MRI) is a new multiplanar imaging technique that clearly demonstrates soft tissue anatomy. The lumbar spines of 26 males have been scanned. From the transverse scans, the position and cross-sectional areas of the muscles of the lumbar region were recorded. Regression analysis was performed to relate these values to trunk measurements and body weight. Sagittal scans were used to measure the angles to the vertical of the lumbar discs and of the skin overlying the spinous processes. The position of each lumbar disc relative to two skin points was measured. These parameters can then be used in biochemical calculations of low-back forces.

Diagnosis of lumbar disc protrusion. A comparison between magnetic resonance imaging and radiculography.

Forty-two consecutive patients with suspected lumbar disc protrusions were studied prospectively to compare the diagnostic accuracy of low-field strength MRI with that of radiculography. Thirty patients subsequently underwent surgical exploration at 33 levels and the operative findings were compared to both methods of diagnostic imaging. All patients had MRI studies, whilst 29 patients also had radiculography. Both studies were evaluated without prior knowledge of the clinical signs, operative findings or the results of other imaging techniques. MRI predicted the correct diagnosis in 29 of the 33 levels explored, an accuracy of 88%. All discs proven to be abnormal demonstrated a reduced signal from the nucleus pulposus. There were two false positive results and two doubtful cases but no false negatives. Radiculography predicted the correct diagnosis in 24 of 32 levels explored, an accuracy of 75%. There were two false positive results, five doubtfuls and one false negative. The overall accuracy when both tests were considered rose to 94%. Of the remaining 12 patients all except one showed good correlation between the MRI and radiculographic findings. These results indicate that low field strength MRI is slightly better than radiculography in diagnosing lumbar disc protrusions.

A comparison between magnetic resonance imaging and scintigraphic bone imaging in the diagnosis of disc space infection in an animal model.

In a controlled prospective study, 33 rabbits were used to compare the efficacy of magnetic resonance imaging (MRI) to scintigraphy in diagnosing pyogenic infection of the intervertebral disc. A suitable inoculum of Staphylococcus aureus (10(8) organisms) was injected into a test level while a similar volume of sterile culture medium was injected into a control disc in each animal. Plain radiographs, MRI, and scintigraphic bone images then were performed at regular intervals after operation. The imaging studies were interpreted blind, as was the final histologic assessment. Five animals died of respiratory complications following sedation. In the remaining 28 animals, 23 developed infection at the test level, and four developed infection at the control disc. Magnetic resonance imaging was found to be more sensitive than scintigraphy in diagnosing discitis, particularly in the early stages of the disease. The overall results showed MRI had a sensitivity of 93%, specificity of 97%, and accuracy of 95%. There were two false-negative results and one false-positive. In contrast, scintigraphy had a sensitivity of 41%, specificity of 93%, and accuracy of 68%. There were two false-positive and 16 false-negative results. Plain radiographs had a sensitivity of 82%, specificity of 93%, and accuracy of 88%. There were two false-positive and five false-negative results. The MRI appearance of discitis was characteristic from an early stage in the disease, and preceded the changes on scintigraphy and plain radiographs by several days in the majority of cases.

Unilateral lumbar facet joint hypertrophy causing nerve root irritation.

We present four cases of massive unilateral lumbar facet joint hypertrophy in an otherwise morphologically normal spine. All presented with a combination of low back pain and symptoms of entrapment of a single lumbar nerve root. The abnormality is best visualised by CT scanning and the results of surgical decompression by partial undercutting facetectomy are favourable.

Magnetic resonance imaging of adolescent disc herniation.

Magnetic resonance imaging (MRI) was used to compare the appearance of the spine in 20 adolescents with proven symptomatic intervertebral disc herniations with that in 20 asymptomatic patients who acted as controls. Abnormality in the signal from the nucleus pulposus of one or more discs was present in all patients, while only four of the 20 controls had any abnormal signals. In all the patients the symptomatic disc produced an abnormal signal and in most a herniated fragment of the nucleus pulposus was identified. Fifteen of the 20 patients had multiple-disc abnormality: six had three abnormal discs and nine had two. This suggests there was an underlying diathesis in patients who later developed disc herniation.

Open reduction or epiphysiodesis for slipped upper femoral epiphysis. A comparison of Dunn's operation and the Heyman-Herndon procedure.

Forty-eight consecutive patients (53 hips) were treated for moderate or severe slips of the upper femoral epiphysis between 1974 and 1984; 46 patients (96%) returned for clinical and radiological assessment at a mean of five years after operation. Twenty-three patients (23 hips) underwent a Dunn's open reduction and 25 patients (30 hips) were treated by epiphysiodesis and surgical osteoplasty as advocated by Heyman and Herndon. The results of the two methods of treatment are compared. Analysis revealed that 11 hips with moderate slip (30 degrees to 50 degrees) treated by the Heyman-Herndon procedure did significantly better than the 18 hips with severe slip (greater than 50 degrees) treated by the same method. Furthermore, when these hips with severe slip were compared to the hips treated by Dunn's open reduction, all of which were displaced greater than 50 degrees, the latter fared significantly better. The authors conclude that the Heyman-Herndon procedure gave consistently good results for moderate slips, but Dunn's open reduction gave better results for hips with severe slips.

The long-term effect of chemonucleolysis on the intervertebral disc as assessed by magnetic resonance imaging.

With Magnetic Resonance Imaging (MRI) it is possible to monitor the changes in water content of the nucleus pulposus after intradiscal injection of chymopapain. In this prospective study the changes that occurred in 20 patients undergoing single-level chemonucleolysis were monitored. A constant pattern of gradual reduction of nuclear signal was seen in all cases. Complete loss of signal took at least 6 weeks and corresponded to the maximum reduction in disc space height. Seventeen patients were scanned at more than 1 year after treatment. Of these, 13 had been treated by chemonucleolysis alone. No significant return of signal from the nucleus pulposus was noted despite a slight reconstitution in disc space height. Chymopapain produced irreversible changes analogous to gross premature disc degeneration. No similar changes were noted in a control group of 12 patients (31 discs) undergoing diagnostic discography without injection of the enzyme.

Combined chemotherapy and surgery for hydatid bone disease.

Surgical treatment of hydatid bone disease is rarely completely successful because radical excision is only possible at certain sites and secondary infection frequently occurs. Antihelmintic drugs have in the past been only palliative due to poor absorption and consequent low concentration in serum or cysts. We report five patients with Echinococcus granulosus infestation treated with a new chemotherapeutic agent albendazole; in two it was given postoperatively, in two pre-operatively and one child is being followed expectantly. We believe that a combination of chemotherapy and surgery may be efficacious in the treatment of hydatid bone disease.

An improved technique of intra-operative bone scanning.

Radiopharmaceuticals have been successfully used to detect occult neoplasms and infective lesions. Bone scans using 99mTc-labelled methylene diphosphonate located osteoid osteomas accurately in a series of 30 symptomatic patients. A portable radiation detector system has been designed to help intra-operative localisation and facilitate complete excision of the lesions with minimal damage to normal tissue. A sodium iodide detector with a fibre-optic link was used at first, but a cadmium telluride system has provided a more durable, reliable and sensitive sterilisable probe.