CT of the Wrist in Suspected Scaphoid Fracture

Bone scan and sagittal projection CT of the scaphoid was performed in 10 patients with clinically suspected scaphoid fractures. The primary and follow-up plain radiographs were negative or equivocal for fracture. CT examination demonstrated scaphoid fracture in 7 patients and normal findings in 3. It is concluded that CT of the scaphoid can replace bone scan to diagnose or rule out fracture in institutions where nuclear medicine facilities are not available.

Conventional Radiography in Transient Synovitis of the Hip in Children

Conventional radiography was performed at diagnosis and at follow-up 5 to 9 months later in 70 children with transient synovitis of the hip. Twenty-four of the patients also had CT examination at diagnosis. The cartilaginous and osseous reaction in the conventional antero-posterior radiographs was studied as was the relation between the radiographic and CT findings concerning fat planes, joint effusion, and position of the hip joint. At diagnosis there was significant increase in the medial joint space and at follow-up examination there was significant increase in medial and cranial joint space, metaphyseal width and acetabular roof width. There was a correlation of a bulging lateral ‘capsular fat plane’ to the position of abduction in the affected hip which explains the asymmetry in the lateral fat plane observed in these patients.

Pitfalls in Ultrasonography of Hip Joint Synovitis in the Child

The normal and abnormal anatomy of the hip joint in childhood was evaluated by ultrasonography (US) with reference to examination technique and errors. When compared with computed tomography (CT), it was confirmed that the two sonographic echoes from the hip joint represent the femoral neck and the external surface of the capsule and that the thickness of the echo received from the capsule depends on the frequency of the transducer. Partial volume effects may simulate or increase the sonographic appearance of hip joint effusion. The normal relationship between joint capsule and femoral neck was established.

Capsular distance in the hip of the healthy child – normal values with sonography and MR imaging

Purpose: To determine the normal values of the anterior and posterior capsular distances of the hip joint in healthy children by means of US, using MR imaging as reference, and to evaluate any possible correlation between age, length, weight and anterior capsular distance (ACD).

Material and Methods: In our first study both hips in 14 healthy children (5-18 years old) were examined with US and MR to obtain measurements of the ACD and the posterior capsular distance (PCD). The distance from the anterior or posterior aspect of the femoral neck to the anterior or posterior aspect, respectively, of the outer limit of the capsule was determined. The distances were measured both with the hips in spontaneous external rotation of 10-15° and in internal rotation of 45°. In our second study, both hips in 28 healthy children (3-16 years old) were examined with US to determine the ACD. Age, length and weight were recorded.

Results: Study I: There was good correlation between the US and MR measurements in all positions. The ACD measured by US was significantly increased in inward rotation of the hip. Study II: There was no correlation between ACD and age, length or weight.

Conclusion: The PCD of the hip joint can be accurately measured by US with the hip in internal rotation of 45°. When compared with MR values, the ACD measured by US was dependent on the degree of rotation of the leg and increased significantly in internal rotation. Because the outer limit of the external layer of the joint capsule is sonographically more distinct, we suggest that the capsular distance should be measured from the outer limit of the joint capsule to the anterior or posterior aspect of the femoral neck. The measurement should be made perpendicular to the femoral neck, at the position where the greatest numerical value is obtained.

Femoral Head Shape in Legg-Calvé-Perthes Disease

Twenty-three children with Legg-Calvé-Perthes disease were examined to determine the femoral head shape. We evaluated and correlated conventional radiography, arthrography and MR imaging. In the a.p. view, measurements were obtained from the center of the femoral head along the bony or cartilaginous outline at 30° intervals. Maximum flattening of the cartilaginous outline appeared laterally, 60° from the center of the baseline of the epiphyseal index and the caput index. Maximum flattening of the bony outline was found at 75°. Arthrography and MR imaging gave the same information about the shape of the femoral head cartilage. The bony femoral head shape on conventional radiographs in the a.p. view did not reflect the cartilage shape obtained by MR and arthrography.

Influence of age, sex, fracture type and pre-fracture living on rehabilitation pattern after hip fracture in the elderly

PURPOSE

To evaluate the influence of background factors on the rehabilitation pattern after a hip fracture in the elderly.

METHOD

Prospective registration based on the Swedish national register for hip fracture patients called RIKSHOFT/SAHFE (Standardised Audit of Hip Fractures in Europe). The place of living was registered both before fracture and during the following four months period (120 days). Graphs were calculated and drawn based on day-to-day changes. Also influences of age, sex, fracture type and type of operation were analyzed.

RESULTS

The patient's pre-fracture functional capacity as evidence by the place they were able to manage to live before the fracture was the most discriminating factor for the rehabilitation; more than sex, fracture type or type of operation. Age was also a highly discriminating factor with a pronounced influence on the rehabilitation pattern.

CONCLUSIONS

These background parameters are very important factors when planning the rehabilitation of hip fracture patients. A strategy with individualized planning of the rehabilitation procedure will be highly necessary in the future, in view of the increasing amount of elderly with hip fractures prognosticated during the coming decades. The knowledge about influencing factors here presented will be useful when planning and performing the rehabilitation for this resource-consuming group of patients.

Sonography in total hip arthroplasty

PURPOSE

The distance between the anterior surface of the neck of the prosthetic stem and the anterior joint capsule, the "capsular distance", is increased in total hip arthroplasty (THA) with synovitis. We evaluated the potential of ultrasonography (US) in measuring the "capsular distance" in THA hips one year after insertion.

MATERIALS AND METHODS

We compared the measurements of the capsular distance using a ruler with those performed with US. A plastic pelvis and femur model with a prosthetic hip and paper tape to simulate the joint capsule were used. We also evaluated the intra- and interobserver agreements between 3 examiners of the US measurements of the anterior capsular distance in 22 patients with THA. The effect of experience in such type of examination was estimated.

RESULTS

There was a high correlation when measuring the anterior capsular distance in the prosthetic hip model with a ruler as compared with US. The interobserver agreement in the US measurements was good and became better after examiners gained experience in this procedure. The intraobserver agreement was always better than the interobserver agreement and also improved with increasing numbers of examinations.

CONCLUSION

Ultrasonography is a reliable method to measure the anterior capsular distance in THA, especially if performed by an experienced examiner.

Mortality and mobility after hip fracture in Japan: a ten-year follow-up

We studied prospectively the change over ten years in mortality, walking ability and place of residence after a hip fracture in 753 patients in Japan. We compared the deaths observed in these patients with those expected in the general population, matched for age, gender and calender year at the time of fracture. The survival rate decreased dramatically for two years after the event and the mortality risk remained higher for ten years. This risk was approximately double that of the general population, even at ten years after fracture. The risk was higher, and remained so for longer, in younger rather than in older patients. The proportion of patients who were able to walk outdoors alone, with or without an assistive device, was 68% (514) before fracture. This decreased to 56% (340) by one year after and remained stable at approximately 63% (125) until ten years. The proportion of patients living in their own home was 84% (629) before fracture, 81% (491) one year later, and then remained stable at approximately 86% (171) until ten years after the event.

Total hip replacement with second generation cementing technique and the monobloc ScanHip: a 10-year follow-up

In 230 consecutive patients 244 hips were operated with a 32-mm cemented prosthesis. The mean age at surgery was 77 (46-96) years. At the 10-year follow-up 89 patients (95 hips) were dead and 33 patients (35 hips) did not attend because of old age or medical problems. Thirteen hips had been revised for aseptic loosening, two for infection, one for recurrent dislocations, and one for fracture. Four hips were found to be loose and seven had suspected radiographic loosening zones but only minor clinical symptoms. No or little limp was experienced by 52% of patients and 62% reported no or little pain. Eighty-seven percent were satisfied with the early postoperative result and 77% were still content at the time of follow-up. On the 10-year radiographs wear of the cups was, on average, 2.2 mm in loose hips and 1.5 mm in intact hips (P=0.02). There was no correlation between dissatisfaction and loosening visible by X-ray at follow-up.

Contamination of polyethylene cups with polymethyl methacrylate particles: an experimental study

The articulating surfaces of 6 ultra-high molecular weight polyethylene cups were exposed to curing polymethyl methacrylate (PMMA) bone-cement and examined with scanning electron microscopy and laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS). Three of the cups were exposed to blood and bone-cement, and the rest were exposed to bone-cement only. After removal of the bone-cement bulk, PMMA particles were found and identified in all 6 cups. The particles were verified by identifying zirconium with energy-dispersive x-ray fluorescence spectroscopy in 5 cups and with LA-ICPMS in 1 cup. The degree of surface contamination was estimated with LA-ICPMS. The number of zirconium-containing particles detected was on average 10 to 20/mm2. PMMA bone-cement left in polyethylene cups during polymerization can contaminate the articulating surface with adherent PMMA particles.

Significance of synovitis in Legg-Calvé-Perthes disease

Synovitis is an important feature in Legg-Calvé-Perthes disease (LCPD) with a significant prognostically negative impact on clinical symptoms, cartilage biochemistry, mechanical properties of the cartilage, joint biomechanics, and prognosis toward healing with a congruent, spherical head of femur. Synovitis causes cartilage edema, deterioration of the cartilage's mechanical properties, cartilage hypermetabolism, and, subsequently, cartilage hypertrophy. This sequence of events could explain the clinical course, which consists of cartilage hypertrophy, lateral subluxation, anterolateral deformation of the head, and, subsequently, joint incongruence in prognostically poor cases of LCPD. A factor in the deformation of the hypertrophic cartilage of the epiphysis is decreased range of motion of the hip, because of pain caused by the increase in intracapsular pressure and the subsequent decrease in the "molding" ability of the acetabulum. Synovitis in LCPD causes an increased intracapsular pressure, the magnitude of which may, in some patients, intermittently compromise the blood supply to the proximal femoral epiphysis. Whether synovitis is the consequence of, or precedes, the loss of blood supply and epiphyseal necrosis is not yet established. Significant and persistent synovitis during the entire course of the disease emphasizes the importance of magnetic resonance imaging as the method of choice for the diagnosis and the prognosis, as well as the monitoring of therapy. The prognostically negative effects of synovitis suggest that more therapeutic efforts should be focused on the treatment of synovitis, from a palliative and prognostic point of view.

Polyethylene wear and synovitis in total hip arthroplasty: a sonographic study of 48 hips

Forty-six patients (48 hips), operated on with cemented total hip arthroplasty (THA) because of arthrosis, were examined radiographically and sonographically at 10-year follow-up. Polyethylene wear of acetabular cups was measured on conventional non-weight-bearing pelvic radiographs, and the volume of polyethylene debris was calculated. Radiographic signs of loosening were identified. The capsular distance (ie, thickness of the synovium or synovial contents) was measured sonographically. We found a significant correlation between increased volumetric wear and increased capsular distance. Hips with radiographically loose acetabular components had significantly greater volumetric wear and capsular distance than those without signs of acetabular loosening. This relationship was not observed in hips with radiographically loose femoral components. In cemented THA, the volume of polyethylene wear debris and the thickness of the synovium and the synovial contents are related. In the event of radiographic loosening of the acetabular component, they are both increased.

Non-operative treatment versus tension-band osteosynthesis in three- and four-part proximal humeral fractures. A retrospective study of 34 fractures from two different trauma centers

Thirty-four patients with three- and four-part proximal humeral fractures from two different trauma centres were studied retrospectively. Sixteen were treated without osteosynthesis and compared with 18 patients treated with tension-band fixation. Fracture classification and clinical examination were made by the same persons in both groups. Most of the three-part fractures healed with good pain relief and good function in daily life but often with a loss of motion. Four-part fractures often led to pain, loss of motion and of function. Conservative treatment seemed superior to tension-band fixation for three-part fractures. Four-part fractures healed with better function and range of motion after tension-band fixation.

Synovitis in Legg-Calvé-Perthes disease. Evaluation with MR imaging in 84 hips

PURPOSE

To evaluate, by means of MR imaging, the degree and persistence of synovitis in the hip joint in Legg-Calvé-Perthes disease and to correlate the degree of synovitis with the degree of epiphyseal necrosis.

MATERIAL AND METHODS

A total of 170 MR images in 72 patients (84 hips) were examined. The T2-weighted MR images were taken in the coronal plane in order to evaluate the degree of synovitis in the hip joint.

RESULTS

MR revealed synovitis in all cases in the early phase of the disease. In Catterall group II, synovitis was discreet to moderate for up to 6 months after diagnosis. Hips with more severe necrosis, Catterall groups III and IV, had moderate or intense degrees of synovitis. There was a correlation between the degree of synovitis and the lateral pillar classification according to HERRING et al. Also, there was a good correlation between the extent of signal changes in the epiphysis on MR imaging and the degree of synovitis. There was no difference when signal changes were evaluated on T1- or T2-weighted images. Signs of synovitis could be seen for up to 30 months after diagnosis in Catterall group I hips, and in Catterall groups II and III for up to 36 months, and in 2 cases even longer. Some Catterall group IV hips had discreet or mild synovitis for 60 months or more, after diagnosis.

CONCLUSION

The degree of synovitis on MR imaging correlates to the extent of epiphyseal necrosis seen on radiographs or MR imaging as well as to the lateral pillar classification, i.e. to a poor clinical outcome. In Catterall group IV hips, synovitis can even persist for up to 60 months after diagnosis.

Migration and wear of long-term successful Charnley total hip replacements

We analysed in-vivo migration and wear over a long period of all-polyethylene acetabular cups which had not been affected by mechanical loosening. The selection criteria of regular radiological follow-up, good clinical outcome (Charnley score of 5 or 6), continued walking without crutches and no radiological signs of loosening of the acetabular cups were fulfilled by 25 Charnley total hip arthroplasties.

Mean migration, measured by the Nunn method, was 0.6 mm in the medial and 0.2 mm in the cranial direction. The mean yearly rate of wear was 0.05 mm and 0.04 mm, with six and two cups having no detectable wear, as measured by the Livermore and Charnley-Cupic methods, respectively. The maximal detected wear was 3.7 mm. There were no changes in the rate of wear with time. Computerised Ein Bild Röntgen Analyse (single-image radiological analysis) measurements of 20 hips indicated plastic deformation of the cups.

We conclude that long-term successful cups do not migrate and have a very low rate of wear which was not affected by ageing of the polyethylene. There was no evidence that polyethylene wear alone caused mechanical loosening of the cup but high rates of wear seem to have an adverse prognostic value in terms of the long-term survival of the prosthesis.

Migration and wear of long-term successful Charnley total hip replacements

We analysed in-vivo migration and wear over a long period of all-polyethylene acetabular cups which had not been affected by mechanical loosening. The selection criteria of regular radiological follow-up, good clinical outcome (Charnley score of 5 or 6), continued walking without crutches and no radiological signs of loosening of the acetabular cups were fulfilled by 25 Charnley total hip arthroplasties. Mean migration, measured by the Nunn method, was 0.6 mm in the medial and 0.2 mm in the cranial direction. The mean yearly rate of wear was 0.05 mm and 0.04 mm, with six and two cups having no detectable wear, as measured by the Livermore and Charnley-Cupic methods, respectively. The maximal detected wear was 3.7 mm. There were no changes in the rate of wear with time. Computerised Ein Bild Röntgen Analyse (single-image radiological analysis) measurements of 20 hips indicated plastic deformation of the cups. We conclude that long-term successful cups do not migrate and have a very low rate of wear which was not affected by ageing of the polyethylene. There was no evidence that polyethylene wear alone caused mechanical loosening of the cup but high rates of wear seem to have an adverse prognostic value in terms of the long-term survival of the prosthesis.

Cumulative revision rate with the Scan Hip Classic I total hip prosthesis. 1,660 cases followed for 2-12 years

We analyzed the cumulative revision rate in 1,474 patients (1,660 hips) operated on with a cemented Scan Hip Classic I prosthesis from November 1983 to January 1994 at Lund University Hospital. The revision rate was analyzed for 3 diagnoses--arthrosis, rheumatoid arthritis and complication after a hip fracture--and for 2 head diameters--22 and 32 mm. Until January 1996, 36 hips were revised: 31 because of aseptic loosening, 3 because of dislocation and 2 because of infection. The overall revision rate was 5.6% after 10 years and was similar in arthrosis, rheumatoid arthritis and fracture cases. Due to revisions because of dislocation in the 22 mm group, the total revision rate was lower in the 32 mm group (p = 0.03).

EBRA improves the accuracy of radiographic analysis of acetabular cup migration

EBRA (Ein Bild Röntgen Analyse) is a new computerized method measuring migration and wear of the acetabular cup, suggested to improve measurement accuracy. We evaluated possible errors of measurement and compared EBRA with standard methods. 1. We did repeated measurements on a single radiograph using the same reference lines. The reliability of the input procedure with standard measurements was significantly better than repeated digitization with EBRA. 2. In a more clinical test, a group of 10 patients was studied. 5 radiographs were taken of the same patient on the same day. EBRA improved the reliability of repeated radiographic examination significantly for migration measurements in the vertical direction. 3. To assess the inter- and intraobserver variations, repeated measurements were performed on the clinical series of pelvic radiographs of 10 patients. EBRA was significantly better than standard methods. With EBRA, errors of wear and migration measurements could be reduced, as compared to standard methods. The major improvement with EBRA was found for migration measurements in the vertical direction.

Functional outcome after hip fracture in Japan

One thousand one hundred sixty-nine elderly Japanese patients who sustained a hip fracture were observed prospectively. Ninety-two percent had operative fracture treatment. Hospital length of stay averaged 67 days; 81% of patients were discharged to their place of residence where they resided before sustaining the fracture. Mortality rates at 120 days, 1 year, and 2 years after injury were 6%, 11%, and 19%, respectively. At 1-year followup, ambulatory status was recovered to that of the level experienced before injury in 67% of patients.

Intracapsular pressure in congenital dislocation of the hip

Intracapsular hip joint pressure was measured in six infants with congenital dislocation of the hip (CDH) or acetabular dysplasia with hip joint instability diagnosed at an average of 4.3 months of age (range: 3-8 months). In the extension and neutral rotation position, the mean pressure was 8.9 mm Hg. After reduction, obtaining stability with the hip joints in the "frog-leg" position (i.e., maximum flexion around the axis of the neck of the femur), the mean pressure was 74.6 mm Hg. When obtaining stability with the hip joints in 20 degrees of flexion, abduction, and inward rotation, the mean pressure was 104 mm Hg, and in approximately 20 degrees of flexion, abduction, and forced inward rotation it was 160 mm Hg. We conclude that these rotational positions, often used to retain the joint in CDH or hip joint instability, induce intracapsular pressures that may cause occlusion of epiphyseal-physeal vessels and thus may be responsible for the avascular epiphyseal necrosis and growth disturbance seen in these patients.

Magnetic resonance imaging and early remodeling of the femoral head after femoral varus osteotomy in Legg-Calvé-Perthes disease

We studied 21 children with Legg-Calvé-Perthes Disease with a prognostically poor development, including lateralization, poor containment, anterolateral flattering, and deformation of the femoral head, as evaluated on serial magnetic resonance (MR) imaging. These children were treated with proximal femoral varus derotation osteotomy. The sphericity of the cartilaginous and bony femoral epiphysis was evaluated postoperatively on serial radiography and MR imaging. There was an early postoperative continuous spherical remodeling over a follow-up period of 3.0 years (1.0-5.1; SD, 1.3).

Epiphyseal bone-marrow abnormalities and restitution in Legg-Calvé-Perthes disease. Evaluation by MR imaging in 86 cases

PURPOSE

By means of MR imaging, to determine signal abnormalities in the femoral epiphysis; to determine their location, extent and restitution over time; and to correlate these findings to the Catterall radiological classification.

MATERIAL AND METHODS

A total of 247 MR images in 86 patients (101 hips) with Legg-Calvé-Perthes disease were examined. The MR images were taken in the coronal plane, and the images through the center of the femoral head were used for this study.

RESULTS

T1-weighted images proved as good as T2-weighted images for the MR evaluation of the extent of the necrosis. In almost every case, the central-cranial part of the epiphysis showed a low initial signal. In Catterall group I, the medial part was never involved. In Catterall III and IV, almost the entire epiphysis showed signal changes. In the period 3-6 years after diagnosis, we still found signal changes in the epiphysis in some hips but there was no correlation with the Catterall classification. After 6 years, the epiphysis showed normal signal intensity in MR imaging. In T1-weighted images, Gd-enhancement occurred in the peripheral regions in the early stages of the disease. The central part of the epiphysis became more enhanced over time and peaked in the period 1-3 years after diagnosis.

CONCLUSION

MR is a valuable modality for monitoring changes in the femoral epiphysis. We propose a new classification of the extent and pattern of epiphyseal bone-marrow abnormalities based on the 4 zones most commonly observed in MR imaging.

Metaphyseal histology and magnetic resonance imaging in Legg-Calvé-Perthes disease

Cylindrical biopsy specimens from the proximal femoral metaphysis were obtained in conjunction with surgery in 22 patients with Legg-Calvé-Perthes disease. The histopathological examination revealed fat necrosis, vascular proliferation, and focal fibrosis indicating previous episodes of ischemia. There was no correlation between the histopathological findings and the corresponding magnetic resonance images.

Intracapsular pressure and loosening of hip prostheses. Preoperative measurements in 18 hips

We measured the intracapsular pressure preoperatively in 18 hips (17 patients) before revision of a total hip arthroplasty because of aseptic loosening. Distension of the joint capsule was measured with sonography in 13 cases. In extension, the mean intracapsular pressure was 26 (0-60) mmHg, in extension and inward rotation it was 159 (24-280) mmHg, in extension and outward rotation it was 30 (3-67) mmHg and in 45 degrees of flexion it was 12 (0-28) mmHg. A mean of 6 (0.5-20) mL of joint fluid was aspirated after the pressure measurements. Sonography showed increased joint fluid/synovial edema and/or increased capsular thickness, as compared to 34 unrevised, radiographically not loose prosthetic hips, and that the capsular distension correlated to intracapsular pressure during extension and inward rotation. We conclude that the intracapsular pressure usually is elevated in a hip joint with loose prosthetic components, that the intracapsular pressure varies with the position of the hip and that capsular distension reflects increased intracapsular pressure. The increased and often very high pressure, varying during gait, may pump debris away from the joint along the interfaces and even by itself cause osteolysis and loosening.

Fusion or stabilization alone for acute distractive flexion injuries in the mid to lower cervical spine?

Long-term pain problems and residual restricted mobility were evaluated for patients sustaining acute distractive flexion injuries to the cervical spine. To assess which of two alternative surgical approaches gives better long-term outcomes, 58 patients were studied, 29 in each group. The results of posterior wire stabilization without fusion according to Brandt were contrasted with those of the Cloward technique. We found significantly more late pain problems and restricted neck mobility in the group treated with wiring without fusion than in those managed with anterior fusion. We conclude that this continuing pain may be due to residual mobility in the damaged degenerated non-fused motion segment, and that the difference between the two groups may reflect the difference in the quality and rate of fusion achieved by the two surgical approaches.

Increased levels of proteoglycan fragments and stromelysin in hip joint fluid in Legg-Calvé-Perthes disease

The concentrations of proteoglycan fragments and stromelysin were analyzed in joint aspirates in 19 children with Legg-Calvé-Perthes disease. We found increased levels of proteoglycan fragments and stromelysin consistent with the presence of synovitis, an important clinical and possibly also prognostic factor in these children.

MR imaging as the primary modality for neuroradiologic evaluation of the lumbar spine. Effects on cost and number of examinations

PURPOSE

To evaluate the effects on cost, and number of primary and supplementary neuroradiologic examinations, after introducing MR imaging as the primary modality in the evaluation of the lumbar spine.

MATERIAL AND METHODS

Two 5-month periods were compared: period 1--before MR; and period 2--after introduction of a 2nd MR device. In period 1, patients were examined with myelography and/or CT after referral from specialists only, whereas in period 2 both specialists and general practitioners could refer patients for MR imaging. The direct cost (neuroradiologic methods and hospitalization) and indirect cost (sick-leave and estimated loss of production caused by the diagnostic procedure) were estimated.

RESULTS AND CONCLUSION

In period 1, investigations were started in 75 patients (62 myelographies and 13 CT examinations); in period 2, in 227 patients (198 MR, 21 CT, and 8 myelographies). The estimated total cost increased from SEK 825,000 to 1,265,000 (53%), the cost per investigated patient decreasing from 11,000 to 5565 (50%), and the cost of preoperative investigation per operated patient decreasing from 8616 to 5563 (35%). The number of supplementary examinations was unchanged.

Polyethylene wear in Scanhip arthroplasty with a 22 or 32 mm head: 62 matched patients followed for 7-9 years

We measured radiographic polyethylene wear in patients with Scanhip arthroplasty and no clinical or radiographic signs of loosening. The patients were divided into 2 groups according to head sizes. 32 patients (33 hips) had an implant with a 22 mm and 30 patients (34 hips) with a 32 mm head. They were followed for 7-9 years. The groups were matched for diagnosis, sex, weight, age, and time of follow-up. The mean linear wear with a 22 mm head was 1.1 mm and with a 32 mm head 1.5 mm (p 0.004), which corresponds to a yearly wear rate of 0.15 mm and 0.18 mm, respectively. The mean difference in volumetric wear was greater, 420 mm3, as compared to 1239 mm3.

Growth in 110 children with Legg-Calve-Perthes' disease: a longitudinal infancy childhood puberty growth model study

Growth in 110 children with Legg-Calve-Perthes' disease (LCPD) was longitudinally followed throughout the growth period. The infancy childhood puberty (ICP) growth model, which has the advantage that reference values can be adjusted for the individual age at pubertal maturation, was used. On the average, the children were slightly shorter at birth and they remained short throughout the entire growth period to maturity. At maturity, the boys were 4.4 cm and the girls were 2.5 cm below the reference mean. The growth velocity was normal at the time of diagnosis, prepubertally, and during puberty. Boys and girls differed only in that the boys were more overweight.

The effect of arthrocentesis in transient synovitis of the hip in the child: a longitudinal sonographic study

Twenty-one children with transient synovitis of the hip were treated in two consecutive groups. In 12 patients aspiration of the synovial effusion was performed within 24 h of admission. In a second group of nine patients no aspiration was performed. There was no other difference in treatment. Joint effusion was studied sonographically in comparison with the nonsymptomatic contralateral hip. Sonography was performed immediately after admission, within 12 h after aspiration, and repeatedly during a follow-up period of up to 15 days. Following aspiration the capsular distention decreased to 49% but recurred within 24 h to 72% of the preoperative value. However, during the first 4 days of follow-up the capsular distention in the aspirated cases was significantly and permanently lower than in the nonaspirated cases. We conclude that arthrocentesis in the acute stage of transient synovitis of the hip in the child permanently reduces the intracapsular effusion.

Measurement accuracy in acetabular cup wear. Three retrospective methods compared with Roentgen stereophotogrammetry

The accuracy of three methods (the simple and noncomputerized Scheier-Sandel and Charnley-Duo methods and the computerized Ein Bild Roentgen Analyse [EBRA] method) for retrospective wear measurements of the acetabular cup from standard pelvis radiographs was studied. Measurements on 13 hip prostheses were compared with those obtained by roentgen stereophotogrammetry analysis. The Scheier-Sandel method had the lowest accuracy and the EBRA method had the best accuracy. The Charnley-Duo method was almost as good when starting analysis 3 months after surgery and is easier to use. The EBRA method is useful for accurate measurements on a small number of patients; the Charnley-Duo method is recommended for clinical wear studies on a larger number of patients.

Intracapsular pressure and pain in coxarthrosis

Intracapsular hip pressure was measured before surgery in 17 patients (18 hips) with coxarthrosis. The results were correlated to pain as registered on a visual analog scale. With the hip in extension, the pressure was 49.5 mmHg (SD, 40.2); in 45 degrees of flexion, it was 21.3 mmHg (SD, 14.6); in extension and inward rotation, it was 105.7 mmHg (SD, 76.0); and in extension and outward rotation, it was 40.8 mmHg (SD, 32.0). A small amount, 0.7 mL (SD, 1.14), of joint fluid was aspirated following pressure registration. Pressure correlated significantly to pain at night, when starting to walk, and on walking. It is suggested that the increase in intracapsular hip pressure is a cause of pain in coxarthrosis, with subsequent limitation of movement and joint contracture.

Sonography and intracapsular pressure in Perthes' disease. 39 children examined 2-36 months after onset

39 children with Legg-Calvé-Perthes Disease (LCPD) and with a radiographically unsatisfactory development were examined with sonography regarding synovitis and with intracapsular pressure recording and aspiration performed 15 (2-36) months after the onset of symptoms. The mean anterior sonographic capsular distension was 3.0 (1.0-7.0) mm greater than that of the contralateral, asymptomatic hip. The mean intracapsular pressure was 4.5 (0-11.5) kPa with the hips in extension and neutral rotation, 9.7 (1.3-27.3) kPa with the hips in extension and inward rotation and 0.9 (-0.8-4.7) kPa in 45 degrees of flexion. We conclude that these children have synovitis as diagnosed sonographically. This synovitis is probably symptomatically and prognostically important in LCPD due to increased intracapsular pressure, with pain, a decreased range of motion and, potential joint contracture.

Femoral head shape in Legg-Calvé-Perthes disease. Correlation between conventional radiography, arthrography and MR imaging

Twenty-three children with Legg-Calvé-Perthes disease were examined to determine the femoral head shape. We evaluated and correlated conventional radiography, arthrography and MR imaging. In the a.p. view, measurements were obtained from the center of the femoral head along the bony or cartilaginous outline at 30 degrees intervals. Maximum flattening of the cartilaginous outline appeared laterally, 60 degrees from the center of the baseline of the epiphyseal index and the caput index. Maximum flattening of the bony outline was found at 75 degrees. Arthrography and MR imaging gave the same information about the shape of the femoral head cartilage. The bony femoral head shape on conventional radiographs in the a.p. view did not reflect the cartilage shape obtained by MR and arthrography.

Prospective comparison of hip fracture treatment. 856 cases followed for 4 months in The Netherlands and Sweden

In a prospective multicenter study 1115 hip fracture patients were registered in Rotterdam (The Netherlands), Sundsvall and Lund (Sweden). The patients had similar background parameters with a mean age of 78 years, about half of them living alone and just above 80 percent coming from independent living. For cervical fracture, hemiarthroplasty was the predominating treatment in Rotterdam (n 169), whereas osteosynthesis was used in Sundsvall (screws n 135) and Lund (hook-pins n 148). The mean (median) hospitalization time was 32 (20) days in Rotterdam, 16 (12) days in Sundsvall, and 17 (10) days in Lund. Discharge to independent living varied from 53 percent in Lund to 72 percent in Sundsvall. Functional outcome (walking ability and ADL capacity) was at 4 months similar in all groups, but at 2 weeks was lower in Rotterdam. Mortality at 2 weeks/1 month/4 months was in Rotterdam 4/9/20, in Sundsvall 2/4/13, and in Lund 0/3/10 percent. Trochanteric fractures were treated by screwplate in Rotterdam (n 146) and Lund (n 78), and by Ender nails in Sundsvall (n 117). The mean (median) hospitalization time was in Rotterdam 39 (29) days, in Sundsvall 24 (15) days and in Lund 19 (11) days. Discharge to independent living varied from 41 percent in Lund to 57 percent in Sundsvall. Functional outcome was similar between the groups. Mortality at 2 weeks/1 month/4 months was in Rotterdam 2/6/14, in Sundsvall 6/12/19 and in Lund 12/12/18 percent. Thus, our study has shown that it is possible to perform a prospective multicenter study involving different European countries.(ABSTRACT TRUNCATED AT 250 WORDS)

The prevalence of gonarthrosis and its relation to meniscectomy in former soccer players

The prevalence of radiographic signs of gonarthrosis and its relation to knee injuries were studied in 286 former soccer players--215 nonelite and 71 elite players--and were compared with 572 age-matched controls with a mean age of 55 years. The prevalence of gonarthrosis among the nonelite players was 4.2%, among the elite players 15.5%, and among the controls 1.6%. Seven of the soccer players had known anterior cruciate ligament injuries, and 40 had had meniscectomies. Of the 32 nonelite players with knee injuries, 4 (13%) had gonarthrosis, and of the 183 without known knee injuries 5 (3%) had gonarthrosis. Among the elite players, the prevalence of gonarthrosis in knees without diagnosed injuries was 11%. We conclude that soccer, especially at an advanced level, is associated with an increased risk for gonarthrosis. After excluding subjects with known knee injuries, there was no difference between nonelite players and controls, but we found a higher rate of gonarthrosis among the elite players.

Size of osteonecrosis of the knee

In the Swedish Multicenter Study of Knee Arthroplasty, 115 knees in 110 patients with knee osteonecrosis represented all reported cases treated with knee arthroplasty in the period from 1975 to 1986. Primary medial femoral condyle osteonecrosis was the most common osteonecrosis reported (89%). Preoperative roentgenograms were staged according to the type of osteonecrosis and classified according to the grade of arthrosis. Detailed measurements of the size of the lesion were also performed. For primary medial femoral osteonecrosis, the width of the lesion averaged 45% of the condyle. The mean width of the lesion (anteroposterior size) was 21 mm and the mean length (lateral size) was 34 mm. The mean depth on lateral roentgenograms was 6 mm. There was a high correlation of results among the various methods of measurement. Using regression analysis, it was possible to approximate the volume of the lesion even from a single measurement of the width on anteroposterior view. The size of osteonecrosis of the knee can be used to plan resection and select the implant design.

Treatment of hip fracture in Finland and Sweden. Prospective comparison of 788 cases in three hospitals

A prospective population-based study of hip fracture treatment was performed during 1989 in the regional hospitals of Oulu (Finland) and Sundsvall and Lund (Sweden). For cervical fractures hemiarthroplasty was preferred in Oulu and osteosynthesis in Sundsvall and Lund. For trochanteric fractures screw-plate was preferred in Oulu and Lund and Ender-nailing in Sundsvall. A shorter mean time at the orthopedic department in Oulu (13 days) was compensated by a lower (14 percent) fraction of patients directly discharged to own home. A somewhat longer mean orthopedic hospitalization time in Sundsvall (19 days) and Lund (17 days) was combined with a higher discharge to own home (49 percent and 35 percent). Prospective multicenter comparisons of treatment combinations (both operation and rehabilitation) permit identification of programs that are optimal for both patient and society.

CT of the wrist in suspected scaphoid fracture

Bone scan and sagittal projection CT of the scaphoid was performed in 10 patients with clinically suspected scaphoid fractures. The primary and follow-up plain radiographs were negative or equivocal for fracture. CT examination demonstrated scaphoid fracture in 7 patients and normal findings in 3. It is concluded that CT of the scaphoid can replace bone scan to diagnose or rule out fracture in institutions where nuclear medicine facilities are not available.

Primary osteonecrosis in the knee evaluated by histopathology and specimen scintimetry related to clinical radiography, scintimetry and MR

Arthroplasty for primary osteonecrosis of the femoral condyle of the knee was performed in 5 patients and the resected pieces of bone were studied histologically. The patients had been given 99 mm-Tc-MDP preoperatively and the scintimetric uptake in the resected bone pieces was determined. All patients had changes typical for osteonecrosis preoperatively on radiographs and scintimetry. In one case MRI investigation was performed. The histological investigation showed necrotic bone with empty lacunae and fatty degeneration corresponding to the osteonecrosis center. A reparative bone formation, osteoblastic activity, cartilage formation and bands of fibrovascular granulation tissue were observed at the borders to intact bone. The scintimetric uptake of the resected bone pieces showed a high uptake corresponding to the osteonecrosis center. The MR examination showed a well demarcated osteonecrotic region. The findings emphasize the localized nature of the osteonecrosis disease.

Measurement accuracy in acetabular cup migration. A comparison of four radiologic methods versus roentgen stereophotogrammetric analysis

Four different methods of radiologic evaluation of the acetabular component migration following total hip arthroplasty have been compared with roentgen stereophotogrammetry, a proven highly accurate method for studying early migration. In the Sutherland and Wetherell method the implant's position is measured with a pencil and a ruler from an ordinary pelvis radiograph. New reference lines of the Wetherell method are thought to be more accurate. The Sulzer and EBRA methods are computerized. In the Sulzer method prominent bone markers are digitized and used as reference points. In the EBRA method a system of tangents on prominent pelvis structure is digitized and used to detect radiographs with similar projection. The implant's position is calculated as the mean position of similar radiographs. The Sutherland, Wetherell, and Sulzer methods had almost the same accuracy, whereas the EBRA method was more accurate and could be used for pro- and retrospective studies in a large number of patients.