Radiographic assessment of sagittal knee instability in weight bearing. A study on anterior cruciate-deficient knees

In 16 patients with chronic, symptomatic anterior cruciate ligament-deficient knees, sagittal displacement was studied in the standing position using fluoroscopic control and a simple device to support the knee. In slight weight bearing all knees but one had normal femorotibial alignment in the lateral view. During full weight bearing sagittal displacements between 2 mm and 17 mm were recorded in 14 patients. The largest displacements were obtained at different angles of inclination of the leg and flexion of the knee joint and were independent of the point of support of the knee joint. The reproducibility of this new standing technique was within 2 mm. A high correlation with previous methods of radiographic measurements of sagittal laxity was found. By the use of the normal relationship between the tibial eminence and the femoral condyles it is possible to record and measure sagittal displacements on a single lateral radiograph of the standing knee joint.

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.

Instability after anterior cruciate ligament rupture. Measurements of sagittal laxity compared in 11 cases

Manual tests and 2 external devices were used together with roentgen stereophotogrammetry (RSA) and an active weight-bearing radiographic method to measure the sagittal laxity in 11 knees with anterior-cruciate-ligament rupture. In 5 knees no ligament surgery had been performed (unstable knees) and in 6 knees a reconstruction had been performed one year before the examination (stable knees). There were positive correlations between all methods, including the manual tests when all knees, both stable and unstable, were analyzed together. However, the mean values of the total displacement differed between the methods, especially when comparing the weight-bearing radiographs with the three other methods. Some knees with substantial displacement during passive loading did not show any displacement when weight bearing; the measurements thus depended on both the ligamentous laxity and the patient's neuromuscular control of the joint. When the stable knees were analyzed separately, higher mean values were recorded with the external devices than with RSA using 180 N load. This could be explained by an error from soft tissue deformation which added to the skeletal displacement when the external devices were used.

Contribution of the umbilical and portal veins to the hepatic blood supply of guinea pig fetuses--an angiographic study

The interlobular distribution of the umbilical and portal venous blood flow within the liver was examined in 35 guinea pig fetuses between 59 and 65 days of gestation. Contrast medium was injected into the umbilical or vitelline vein, and its passage through the liver was monitored by serial angiography. In four experiments, injections were made into both the umbilical and vitelline veins of the same fetus. To ease interpretation of the angiograms obtained in vivo, we also made a postmortem examination of livers in which the venous system had been filled with an aqueous suspension of barium sulphate in gelatin. These combined experiments demonstrated no passage of contrast medium from the placenta to the inferior vena cava, which is in accordance with independent evidence that the term guinea pig fetus lacks a functional ductus venosus. The area supplied by the umbilical and portal veins was clearly and consistently delineated. The umbilical vein supplied the left lobe and the left sublobe of the quadrate lobe. The portal vein supplied the right lobe, the smaller caudate lobe, and all or most of the right sublobe of the quadrate lobe. This pattern of distribution appears to be determined by flow and pressure gradients within the hepatic circulation.

Cartilage regeneration after proximal tibial osteotomy for medial gonarthrosis. An arthroscopic, roentgenographic, and histologic study

High tibial osteotomy for medial gonarthrosis was performed in 28 patients (28 knees). At the time of surgery, arthroscopy was also performed and a cartilage-bone biopsy was obtained. Postoperatively, 15 patients were randomized to a cylinder plaster cast, whereas 13 patients had a hinged cast brace for early knee mobilization. At follow-up examination, two years after surgery, 16 patients accepted an arthroscopic examination with a cartilage-bone biopsy. In overcorrected knees, cartilage regeneration was found in eight of 14 patients on the medial tibial condyle and in nine of 14 on the medial femoral condyle. The main repair feature was proliferation of fibrocartilage, which covered bone and areas of fibrillated cartilage and filled vertical clefts in hyaline cartilage. The hyaline cartilage showed an increased cellularity with numerous nests of proliferating chondrocytes. No correlation was found between clinical outcome and the degree of cartilage regeneration as observed by arthroscopy, biopsy, or roentgenography. Knees with a brace postoperatively had better knee flexion two years after surgery. No difference in cartilage regeneration was recorded between knees with a plaster cast or a cast brace postoperatively.

The natural history of recurrent dislocation of the patella. Long-term results of conservative and operative treatment

From 1970 to 1978, 29 patients had a unilateral operation for bilateral recurrent dislocation of the patella. We examined 21 of them at a mean of 14 years postoperatively. Eighteen of these patients had evidence of generalised joint laxity. Six of the operated knees and four of the unoperated knees still had recurrent dislocations. The operated knees were clinically worse, with a significantly higher incidence of osteoarthritis. We concluded that the operations used to treat recurrent dislocation of the patella may have had short-term benefits, but did not cure the patients in the long term.

Prognosis for patients with medial gonarthrosis. A 16-year follow-up study of 189 knees

All 189 knees (157 patients) that had had primary medial compartment arthrosis in 1972 were followed until 1988. After 14 years, tibial osteotomy had been performed in 85 knees and arthroplasty in 33 knees. No major surgery had been performed in 71 knees; of these 71 knees, 31 patients (40 knees) had died. Of the remaining 23 patients (31 knees), the majority had an unsatisfactory knee and managed only on a low activity level. In 20 of 24 knees, progress of the arthrosis was recorded roentgenographically. Because natural course of medial gonarthrosis has a poor prognosis, the majority of patients suffering from this condition will eventually have major knee surgery.

Proteoglycan epitope in synovial fluid in gonarthrosis. 28 cases of tibial osteotomy studied prospectively for 2 years

High tibial osteotomy was performed for medial gonarthrosis in 28 patients. Preoperatively, and at 3, 12, and 24 months after surgery, clinical and radiographic examinations were made, and joint-fluid samples were aspirated. Arthroscopy was performed preoperatively and at 24 months. Immunoassay of proteoglycan epitope in joint fluid showed an increase in concentration at all times as compared with a reference population with normal knee joints. An increase in both the concentration and the total amount of proteoglycan epitope in joint fluid was noted at 3 months postoperatively with a return to preoperative values at later times. Regrowth of fibrocartilage did not correlate with proteoglycan epitope data.

Legg-Calvé-Perthes disease: imaging with MR

Magnetic resonance (MR) imaging studies were obtained to evaluate the shape of the cartilaginous femoral head and the adequacy of femoral acetabular containment in 35 children with Legg-Calvé-Perthes disease (LCPD). MR results for 24 of the 35 children were compared with results at arthrography. The shape of the cartilaginous femoral head was well identified with MR imaging, but, with arthrography, less information could be obtained about the medial and lateral aspects of the cartilaginous capital epiphyses in nine and three cases, respectively. Thirteen children underwent surgery; remodeling and regained femoroacetabular congruity of the articular surfaces following derotation varus osteotomy was identified in seven of 10 who underwent repeat MR imaging. In addition, MR images and conventional radiographs of the hips were compared. The radiographically identifiable distribution of the bone necrosis of the capital epiphysis correlated well with that demonstrated on MR images. MR imaging is a valuable non-invasive procedure with which to obtain information about the status and treatment of the cartilaginous femoral head in children with LCPD.

Ten-year results of tibial osteotomy for medial gonarthrosis. The influence of overcorrection

The results in relation to the correction achieved 1 year after surgery of a series of tibial osteotomies in 50 patients (52 knees) are presented with a total observation time of 10 years. Mean age at the time of osteotomy was 56 years. Overcorrected knees had a significantly better result after 10 years. Progress of gonarthrosis occurred in 6/34 overcorrected knees compared with 3/4 in the normo- and undercorrected group. One out of 34 overcorrected knees recurred in varus. Five knees were revised by knee arthroplasty or reosteotomy one of which was overcorrected.

Improved positioning of the femoral stem with a centralizing device

Two series of patients operated on with total hip replacements for arthrosis are reported. The same prosthesis and operative and cementing techniques were used in both series, except that in Series 2 a centralizing device consisting of four triangular fins passed over the tip was also used to improve the positioning of the femoral stem. It was found that the position of the tip was more central in Series 2. No drawbacks were associated with the use of the device. We concluded that the centralizing device facilitated the positioning of the femoral stem tip.

CT scans and lipohaemarthrosis in hip fractures

Computed tomography was performed on 40 patients with recent hip trauma. Radiographs of 25 showed a fracture of the femoral neck with slight displacement; 24 of these had intra-articular fluid and 20 had a lipohaemarthrosis on the CT scan. In 15 patients, radiographs at the time of admission were normal but suspicion of fracture remained. A fracture was later verified in five patients, four of whom had lipohaemarthrosis on admission. In the remaining 10 patients no fracture could be detected; only one patient had a hip joint effusion but no free fat. Thus all 24 patients with lipohaemarthrosis had an intracapsular fracture of the hip. We suggest CT for patients with hip trauma and negative radiographs. The presence of a lipohaemarthrosis of the hip strongly suggests an intra-articular fracture of either the femoral neck or the acetabulum.

Diagnosis of displaced ulnar collateral ligament of the metacarpophalangeal joint of the thumb

In a prospective study of 24 consecutive patients with posttraumatic instability of the metacarpophalangeal joint of the thumb, clinical examination including instability tests and palpation of displaced ulnar collateral ligaments was used to separate the patients into two groups--nondisplaced and displaced ruptures. Palpable displaced ruptures were treated surgically, whereas nonpalpable ruptures were interpreted as nondisplaced and were treated with plaster, irrespective of the instability. At follow-up 1 year later both groups showed similar results with respect to stability, strength, and function. Our results indicate that a clinical examination with palpation of the torn ligament ends identifies displaced ruptures of the ulnar collateral ligament, i.e., those cases needing surgery. Nondisplaced ruptures might be treated nonoperatively.

Revision after osteotomy for gonarthrosis. A 10-19-year follow-up of 314 cases

During a 10-year period, 314 tibial osteotomies were performed for medial gonarthrosis. At follow-up after 10-19 years, 62 knees had been revised by arthroplasty (52 cases) or reosteotomy (10 cases). The revision rate was 54/170 in undercorrected knees and 8/144 in knees with normalization or overcorrection of the hip-knee-ankle angle. Our results confirm that tibial osteotomy for gonarthrosis requires proper indications and precise surgery. Perhaps, given another 10 years, our osteotomies will have outlived contemporary arthroplasties.

Early knee mobilization after osteotomy for gonarthrosis

In a prospective study, 32 knees in 32 patients were randomized to either a cylinder plaster cast (17 knees) or hinged cast-brace (15 knees) after high tibial osteotomy for medial gonarthrosis. At 6 weeks, 3 months, and still 1 year after surgery, the range of motion was better in the cast-brace group. There was no difference in the other clinical results at 3 months and at 1 year after surgery, nor in changes of osseous correction or in the final knee alignment. All the patients in the cast-brace group were satisfied with early motion.

Function after tibial osteotomy for medial gonarthrosis below aged 50 years

Twenty-seven patients (28 knees), with a median age of 42 (27-50) years treated with a high tibial osteotomy for early medial gonarthrosis (Ahlbäck's Stage I) were examined after 11 (7-18) years. Twenty-four were men; 18 knees had had previous meniscus and ligament lesions. At follow-up, 22 knees were satisfactory and 9 patients managed high-activity sports or heavy work. In 25/28 knees, the arthrotic process had not progressed radiographically.

Anomalous lumbosacral articulations and low-back pain. Evaluation and treatment

Eleven patients ranging from 13 to 76 years in age with low-back pain and asymmetric sacro-transverse joints were studied. Preoperatively, scintimetry was performed in eight of the patients, in all cases with normal results. Ten of the 11 patients had their sacrotransverse joint anesthesized in fluoroscopy. Nine of these experienced pain reduction or alleviation. Resection of the transverse process was performed in all cases. At follow-up, at 6 to 42 months postoperatively, seven patients reported total alleviation of pain, and two, significant improvement. Two patients had unchanged symptoms; one patient was 76 years of age, had associated degenerative changes of the spine, and had no effect of local anesthetics in his joint, and the other was a 13-year-old male competitive swimmer. The authors conclude that, in patients with anomalous unilateral lumbosacral articulations and low-back pain, in whom local anesthesia into the joint gives pain alleviation, resection of the transverse process may be a worthwhile procedure.

Lateral meniscal lesions in patients with clinically suspected medial lesions

Double-contrast arthrography and arthroscopy were performed in a prospective study on 46 consecutive patients clinically suspected of having a medial meniscal tear only. At arthrography, 38 torn medial menisci were found; four of them were, however, false-positive and another false-negative as compared with arthroscopic examination. Moreover, seven unsuspected lateral meniscal tears were diagnosed at both arthrography and arthroscopy. The diagnostic accuracy of the double-contrast arthrography was well above the clinical accuracy, and we conclude that arthrography is a reliable method for diagnosing both medial and lateral tears.

A guide instrument for high tibial osteotomy

Fifty-two patients (52 knees) with medial gonarthrosis were subjected to high tibial osteotomy using the Tjörnstrand guide instrument. The intended wedge was calculated from a whole lower limb radiograph. The correction aimed at was an overcorrection of 4 degrees in valgus of the hip-knee-ankle angle. All but 1 case were corrected to +/- 3 degrees of the intended angle. All but two cases healed within +/- 3 degrees of the achieved surgical correction, i.e., a substantial improvement compared with our previous freehand technique where one fifth were outside this interval. We conclude that in knee surgery a guide is as important for osteotomies as for arthroplasties.

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.

Proximal closing wedge osteotomy and adductor tenotomy for treatment of hallux valgus

After 2 to 4 years, 25 patients (27 feet) who had a proximal closing wedge osteotomy of the first metatarsal and an adductor tenotomy were reviewed. A total of 20 patients (22 of 27 feet) were completely satisfied; 5 patients not completely satisfied had metatarsalgia because of dorsal displacement of the first metatarsal head. Radiographic measurements showed a narrowing of the forefoot rather than a large change in the intermetatarsal angle. The recovery period was long, an average of 11 weeks. Pin inflammation occurred in 5 patients and incisional neuromas in 2 patients. The risk of these complications must be taken into consideration when using this operation.

The PCA unicompartmental knee. A 1-4-year comparison of fixation with or without cement

Totally, 93 knees were operated on with the PCA unicompartmental knee for gonarthrosis Stages I-III according to Ahlbäck. The clinical findings for 84 arthroplasties with 1-4 years' follow-up showed 82 excellent or good results. The mean postoperative flexion was 124 degrees. The position of the tibial component was respectively 86 degrees and 89 degrees in the AP and lateral views. The mechanical axis was slightly undercorrected. There were two failures, both with persistent pain on walking. One failure was among 43 uncemented knees, whereas the other was among the 41 cemented arthroplasties. Four uncemented arthroplasties had a first steps' problem but were satisfactory otherwise. There was no infection or clinical loosening. A reoperation was performed in 1 case, in which a symptomatic osteophyte was removed. When compared with our earlier Marmor series, the PCA unicompartmental arthroplasties were better. The cemented arthroplasties had a somewhat higher frequency of complete pain relief. An uncemented arthroplasty should only be considered in special situations.

Hemarthrosis after femoral neck fracture fixation

In 34 femoral neck fractures, CT was performed within 1-32 days after internal fixation. All the cases except one showed an increased distance between the femoral neck and the anterior aspect of the joint capsule as compared with the intact side, indicating varying degrees of hip joint effusion and/or synovitis. Hip joint aspiration in 11 patients revealed increased intracapsular pressure varying between 10 and 112 mmHg and volumes of aspirated joint effusion up to 23 ml. Pain relief and increased joint motion after drainage of the intracapsular effusion was observed in 3 patients whose postoperative mobilization was facilitated.

The vertical position of the patella. A new radiographic method for routine use

Patella height was defined by the distance between the midpoint of the articular surface of the patella and the condylar plane, which was constructed perpendicular to the mechanical axis of the tibia. In two series of normal individuals the measured distances were related to body height and the length of the lower leg and thus expressed as its ratio, which was the same in both sexes. The measurements were performed on lateral radiographs of the knee and lower leg obtained in weight-bearing and 30 degrees to 40 degrees of knee flexion using a simple device to obtain a standardized position of the lower leg during the examination. The standing position is proposed for these measurements since the patellar ligament is shorter in the recumbent position. The method can be used for biomechanical analysis of the femoropatellar joint.

Lesion of the anterior cruciate ligament and sagittal disalignment of the knee in weight-bearing

Twenty-nine patients with late reconstructive surgery for anterior cruciate ligament lesions had a clinical and radiologic follow-up ten years after injury. Anterior sagittal displacement of the tibia was recorded on the routine standing radiographs in 16 knees all having a normal femoro-tibial alignment in the non-weight-bearing position. Five of eleven patients with sagittal displacement of between 10 and 19 mm had early osteoarthrosis, which was confirmed by magnetic resonance imaging in four cases; their ages ranged from 23 to 38 years. No radiographic signs of osteoarthrosis were observed in those with displacements of less than 10 mm. In some patients there was a discrepancy between the clinical and radiographic measurements of instability. In addition to the clinical tests of instability standing rather than non-weight-bearing lateral radiographs are suggested for the routine assessment of cruciate ligament injuries.

Gadolinium-DTPA enhancement of soft tissue tumors in magnetic resonance imaging--preliminary clinical experience in five patients

In a preliminary report of a clinical trial of gadolinium-DTPA (Gd-DTPA) for enhancement of soft tissue tumors in magnetic resonance imaging (MRI), experience of the first five cases is presented. Enhancement was found to give better delineation of the tumor in richly vascularized parts of the tumors, compressed tissue immediately surrounding the tumor, and in atrophic, but richly vascularized, muscle.

Radiography and scintigraphy in the assessment of early gonarthrosis

The radiographic and scintigraphic appearances in early gonarthrosis were compared in 62 knees. Early femorotibial osteoarthrosis was found to be confined to one compartment (medial or lateral) of the joint. However, concomitant patellofemoral osteoarthrosis was common. 99Tcm-MDP scintigraphy was consistently positive when the joint space (femorotibial and patello-femoral) was reduced by 75 per cent or more. Joint space narrowing by as much as 50 per cent could be observed in a scintigraphically normal knee. The inconsistency between the radiologic and scintigraphic findings in the earliest stages of gonarthrosis points to the importance of appropriate radiographic technique.

Preoperative diagnosis of soft tissue tumours

Over a period of 3 years in Southern Sweden 35 patients were seen with deep-seated limb sarcomas without metastases, 30 of whom were referred before any operation had been carried out. Thirty seven patients with deep-seated benign lesions were referred during the same period because of suspected malignancy. A preoperative diagnosis considered sufficient for a definitive operation was made from the clinical findings, aspiration cytology and radiographic examination, but without open biopsy, in 59 of these 67 cases. The differentiation between a benign and a malignant tumour was correct in all but one. The extent of excision necessary to achieve adequate margins for a soft-tissue sarcoma can often be reduced if open biopsy is avoided, with preservation of function. We conclude that treatment without open biopsy is possible in the great majority of patients with soft-tissue sarcoma.

Acetabular fracture causing hip joint tamponade. A case report

An 81-year-old woman had severe hip pain after a fall. Radiography was normal, but computed tomography and sonography showed a minor, displaced acetabular fracture and hemarthrosis. Aspiration of 15 ml of blood reduced the intracapsular pressure in the neutral position from 30 kPa to atmospheric pressure with relief of pain and increased joint motion. This case confirms that acetabular fracture may escape radiographic diagnosis and cause hip joint tamponade. Aspiration should be considered as a palliative and possibly therapeutic measure.

Digital radiography of the spine, large bones and joints using stimulable phosphor. Early clinical experience

The value of digital radiography in musculoskeletal disorders was investigated by assessing its ability to depict anatomic structures and common radiologic features as compared with the conventional film-screen combination. The digital image that was frequency modified was superior to conventional films in delineating soft tissue structures and for areas with large attenuation differences. The conventional film-screen system was superior in depicting small anatomic structures and in identifying the zone close to prostheses. This was explained by the high spatial resolution of the conventional film system and the disturbing halo effect around the prosthesis seen with digital images. The halo effect is an overshoot caused by the unsharp masking operator, which was in this series not changed for individual examinations. The exposure (radiation dose) could be reduced to 50 per cent using the digital system, without any loss of information.

Computed tomographic sinography in orthopedic radiology

Twenty-one computed tomographic (CT) and 17 conventional sinographies were performed on 17 patients with lesions in the musculoskeletal system. The CT sinography was superior to the conventional examination in all cases, giving detailed information on the relationship between the sinuses and neighboring soft tissue and skeletal structures. CT sinography is recommended as the primary method for examination of musculoskeletal sinuses.

Intracapsular pressures in undisplaced fractures of the femoral neck

We studied intracapsular pressure in 50 patients with Garden Grade I and II subcapital fractures. Before operation pressures varied from zero to 320 mmHg, 16 patients having an intracapsular pressure of over 80 mmHg. The pressure was increased considerably by medial rotation and decreased by lateral rotation and especially by semi-flexion. From zero to 36 ml of blood was aspirated; the amount did not correlate with the intracapsular pressure. Of 25 patients who were also examined by scintimetry, 13 had reduced uptake at the femoral head before aspiration, and nine of these showed a marked increase in uptake after aspiration. Intracapsular tamponade of the hip may be one reason for the occasional occurrence of segmental collapse of the femoral head after subcapital fracture with minor displacement.

MR imaging of the cervical spine in rheumatoid arthritis

The cervical spine was examined with MR imaging and conventional radiography in 23 patients with severe rheumatoid arthritis. All patients had neck pain and 17 also had neurologic symptoms. MR provided detailed information about soft-tissue lesions, vertebral dislocation, and narrowing of the spinal canal. Pannus surrounding the odontoid process was revealed in 14 patients, all with horizontal atlantoaxial subluxation. Compression of the medulla and/or spinal cord, caused by dislocated vertebrae and/or the soft-tissue mass around the odontoid process, was seen in 15 patients. When there was more than one dislocation the most important level could be determined. Posterior occipitocervical fusion had been performed in six of the patients, and in only two of these was adequate analysis of the upper cervical spine impossible because of artifacts from metal (stainless steel wires and pins). Sagittal MR in the neutral position combined with conventional radiography, including lateral views in flexion and extension, provided all the information necessary for further clinical management of rheumatoid arthritis of the cervical spine.

Recurrent shoulder dislocation and screw failure after the Bristow-Latarjet procedure. A case report

A 22-year-old male was operated on with coracoid transfer according to the Bristow-Latarjet procedure because of recurrent anterior dislocation of his right shoulder. Nine months later the patient sustained a repeat shoulder dislocation after moderate trauma. The screw was radiographically found to be bent. Subscapularis shortening according to Putti-Platt was performed. No repeated episodes of dislocation and no instability has been experienced by the patient since then. However, one year later, he awoke with pain dorsal to the humeroscapular joint. Radiographs showed the screw to be broken. The proximal part of the screw was located underneath the humeroscapular joint and was removed. After this, the patient was free of pain and returned to work as a carpenter.

The potential of computed tomography in visualising structures inside the metal cup in surface-replacement total hip arthroplasty

Computed tomography (CT) was employed to evaluate the femoral component of the prosthesis in surface-replacement total hip arthroplasty in seven patients suffering from rheumatoid arthritis. Image reconstruction using the high frequency filter resulted in an image of the cement-bone interface inside the cup which allowed the detection of bone resorption. This new application of CT could prove to be a valuable complement to conventional methods in the radiological assessment of metal cup arthroplasties.

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.

Sonography and joint pressure in synovitis of the adult hip

Sonography was successfully used to diagnose an effusion in the hips of three adults with septic arthritis and four with aseptic synovitis. The effusions were confirmed by aspiration. All the patients had markedly increased intracapsular pressure which, in the extended position, exceeded the systolic blood pressure and could well compromise the blood supply to the head of femur. Aspiration reduced pain and intracapsular pressure, as did flexion of the hip to 45 degrees.

Sonography in septic arthritis of the hip in the child: report of four cases

Sonography was used successfully in the investigation of septic conditions in the hip region of four children. In two patients, septic arthritis of the hip was confirmed; in two patients, intracapsular involvement was excluded in osteomyelitis of the hip region.

Computed tomography of humeral head cup arthroplasties. A preliminary report

Computed tomography (CT) was employed to evaluate resurfacing metal cup arthroplasties, in shoulders affected by rheumatoid arthritis. Reconstruction of the information obtained, with the high frequency filter, resulted in an image of the cement and skeletal structures inside the cup. This new application of CT may prove valuable in assessing the complications and results of cup arthroplasties.

Cup arthroplasty of the rheumatoid shoulder

Hemiarthroplasty of the humeral head, using a stainless steel cup, was performed in 26 shoulders of patients with rheumatoid arthritis who had severe pain and loss of function. All the shoulders were Larsen's radiographic Grade 4 or 5. After 2 (1-5) years, all the shoulders were painless and had satisfactory function. Partial radiolucent zones exceeding 1 mm were seen in three shoulders.

Sonography, arthroscopy, and intracapsular pressure in juvenile chronic arthritis of the hip

Sonography was used in the preoperative evaluation of the hip joint in 14 patients with juvenile chronic arthritis (JCA). The joint capsule distension found at sonography and the intracapsular pressure were increased in patients with severe synovitis revealed at arthroscopy. Sonography and intracapsular pressure-recording can be recommended for assessments of synovitis of the hip joint in JCA.

Hemarthrosis in undisplaced cervical fractures. Tamponade may cause reversible femoral head ischemia

In eight undisplaced intracapsular fractures of the femoral neck, an intracapsular hematoma was diagnosed by computed tomography. 99mTc-MDP scintimetry revealed markedly reduced or absent blood supply to the head of femur. The intracapsular pressure was 23 (2.7-43) kPa with the hip in neutral position. Following aspiration of 12 (0.5-36) ml of blood, pressure was reduced to zero, and postaspiration scintimetry revealed restitution of blood supply to the femoral head. Hip joint tamponade in these patients has caused femoral head ischemia, reversible by aspiration.

Computed tomography and ultrasonography for diagnosis of hip joint effusion in children

Nineteen consecutive children with transient synovitis of the hip were examined for intracapsular joint effusion using computed tomography (CT) and ultrasonography (US). The two techniques were highly correlated in measurements of the anterior displacement of the joint capsule, indicating both to be reliable diagnostic tools. Such an effusion is clinically important because of the increase in intracapsular pressure with ensuing disturbance in the vascular supply to the proximal femoral epiphysis, as demonstrated experimentally and clinically in transient synovitis.