Bilateral intraosseous lipoma of the calcaneus. A case report

A case of bilateral intraosseous lipomas of the calcaneus is presented. The bilateral localization of calcaneal intraosseous lipomas is extremely rare.

Fibrous dysplasia arising from the calcaneus

A case of an 18-year-old woman with fibrous dysplasia arising in the calcaneus, which is extremely rare, is reported, with the emphasis placed on differential diagnosis from low-grade central osteosarcoma. She had a severe pain in her left ankle after sprain. Plain radiographs showed a radiolucent lesion measuring 6.3 x 2.5 cm with a sclerotic margin in the left calcaneus. CT scans showed a well-defined lytic lesion with disruption of the lateral cortex and an ossification or calcification in its center. On MR imaging, the lesion had isointensities and high intensities on T1 and T2 weighted images, respectively, but its central portions showed lower intensities both on T1 and T2 weighted images. The lesion was enhanced with gadolinium except for the central portions. The specimen obtained by open biopsy consisted of fibrous tissue and foci of irregular woven bone. None of the nuclear atypia, mitoses, longitudinal stream of bone or invasive nature of growth was detected. The diagnosis of fibrous dysplasia was histologically made. The lesion was curetted and packed with autogenous bone chips. No evidence of recurrence was noted postoperatively.

Hematogenous calcaneal osteomyelitis in children

This study reviewed 21 cases of hematogenous osteomyelitis of the calcaneus in skeletally immature patients. The average patient age was 2.9 years. Local tenderness, swelling, and erythema were the most common findings. The erythrocyte sedimentation rate was elevated in 20 (95%) of 21 patients, whereas the C-reactive protein was abnormal in only seven (47%) of 15 patients tested. Nine patients had positive cultures, with Staphylococcus aureus being the most common organism. Plain films showed a lytic lesion in 15 (71%) of 21 cases, whereas scintography was positive in all 16 cases scanned. Ten patients were treated with antibiotics alone, whereas 11 patients underwent surgical irrigation and debridement in association with antibiotic therapy. Seventeen patients returned for follow-up, and although only one was symptomatic, three of 10 follow-up radiographs revealed residual abnormalities of the calcaneus.

MRI-induced retrocalcaneal bursitis

This case report describes a patient with acute retrocalcaneal bursitis, which developed after MRI examination of the ankle. The sagittal T2*-weighted gradient echo sequence revealed an extensive susceptibility artifact in the area surrounding the Achilles tendon near its insertion at the os calcis. This artifact was caused by postsurgical metallic particles. We postulate that these particles were mechanically stimulated by the magnetic field and induced the inflammatory response.

Synovial osteochondromatosis of the retrocalcaneal bursa: a case study

A 42-year-old man presented with synovial osteochondromatosis (SO) of the retrocalcaneal bursa with intraosseous lesions in the calcaneum, leading to significant pain and consequent disability. Simple x-rays, computed tomography, and magnetic resonance imaging were performed preoperatively. The patient has remained asymptomatic, clinically and radiographically, without recurrent lesions for 18 months postoperatively.

Nonoperative treatment of posterior tibial tendon dysfunction

One of the most common causes of acquired flatfoot deformity in adults is dysfunction of the posterior tibial tendon. The main function of the posterior tibial tendon is to invert the midfoot and lock the transverse tarsal joints (talonavicular and calcaneocuboid joints). When the tendon fails to function properly, a progressive flatfoot deformity develops. Because the disease process is a continuum, a staging system has been devised to offer guidelines for nonoperative and operative treatment of this problem. The rationale for nonoperative treatment of this disorder is to support the longitudinal arch and to decrease the valgus angulation of the calcaneus for flexible flatfoot deformity, and to immobilize and support the hindfoot and midfoot for rigid flatfoot deformities. The success of nonoperative treatment first requires the assessment of the flexibility of the flatfoot deformity. For a flexible deformity, the custom orthosis should be fitted with the foot and ankle in a corrected position as close to the neutral position as possible. Whereas, for a rigid deformity, it is imperative for the custom orthosis to be fitted with the affected foot and ankle in an in situ position.

[Solitary juvenile cyst of the heel bone. Two case reports and review of the literature]

The calcaneus is a uncommon site for a unicameral solitary bone cyst. However, because of the concentration of forces through the heel, such solitary bone cysts are usually symptomatic, depending on the proximity to the joint and the size of the cyst and therefore require in most cases surgical treatment. This is a report about two patients with a solitary bone cyst of the os calcis in 1996 and 1997. The diagnosis was confirmed radiologically and histologically. The standard therapie in both cases was the curretage of the cyst by packing the defect with bone graft from the pelvis. The author reviewed the literature concerning ethiology, diagnosis and treatment of unicameral solitary bone cysts of the calcaneus. The diagnosis cannot be based solely on radiological findings because of the variation of solitary bone cysts and the special forms, such as calcifying solitary bone cysts. Therefore exact histological diagnosis is of particular importance.

An accessory ossification centre in the calcaneus with talonavicular and second metatarsocuneiform coalitions

We present the case of an 11-year-old girl with an accessory ossification centre of the calcaneus with talonavicular and second metatarsocuneiform coalitions, and bilateral os tibiale externum.

Magnetic resonance imaging of the normal and injured lateral collateral ligaments of the ankle

BACKGROUND AND AIMS

To study the role of MR Imaging in evaluating both normal and injured lateral collateral ligaments of the ankle.

MATERIALS AND METHODS

Twenty-four patients with clinically diagnosed inversion injury to the ankle and 20 healthy volunteers underwent Magnetic Resonance Imaging (MRI) of the ankle with special emphasis on the lateral complex ligaments.

RESULTS

The anterior talofibular (ATFL) and posterior talofibular ligaments (PTFL) were identified in 100% of the ankles of normal volunteers in the axial plane. The PTFL was identified in 100% in the coronal plane. The calcaneofibular ligament (CFL) was identified in 76% of the ankles in the axial, 84% in the coronal and 88% in the sagittal plane. Of the 24 patients with inversion injury, MRI showed ligament abnormalities in 16 patients, ten of these were isolated ATFL tears, five had combined ATFL and CFL tears and one case showed in addition abnormal signal in the PTFL. MRI revealed associated injuries to other ligaments and other soft tissue and osseous structures of the ankle in twelve patients.

CONCLUSION

MRI is a non-invasive, accurate technique for evaluation of the normal and injured lateral collateral ligaments of the ankle.

Clubfoot analysis with three-dimensional foot models

The purpose of this study was to develop a method of defining, in mathematical terms, the interpositional relationships of the bones of the hindfoot complex in the idiopathic clubfoot and the neurogenic clubfoot. The neurogenic clubfoot and contralateral normal-appearing foot of a stillborn infant with myelomeningocele, and the normal foot of a 10-year-old were sectioned with a cryomicrotome. Magnetic resonance images (MRIs) of the clubfoot and the normal foot of a 3-month-old boy were obtained. Using a computer program, three-dimensional foot models were generated from the digitized cryomicrotome sections and from the MRIs. The central principal axes were determined for the talus and calcaneus. The long central principal axes of the talus and calcaneus were neutrally rotated with reference to the bimalleolar axis in the idiopathic clubfoot while in the neurogenic clubfoot the long central principal axis of the talus was medially rotated 52 degrees and that of the calcaneus 10 degrees. The talocalcaneal angles defined by the long central principal axes in the superior and medial views were 0 degree and 10 degrees, respectively, in the idiopathic clubfoot, and 42 degrees and 56 degrees, respectively, in the neurogenic clubfoot.

Ewing's sarcoma of os calcis: case report with a review of literature

A rare case of Ewing's sarcoma of os calcis is described here. Its atypical clinical and radiological features often delay the diagnosis. These features and review of literature are discussed.

[MRI of plantar fasciitis]

PURPOSE

The purpose of this study was to determine the type and frequency of characteristic bone and soft tissue changes on MRI of patients with a clinical diagnosis of plantar fasciitis.

MATERIALS AND METHODS

28 patients with a clinical diagnosis of plantar fasciitis underwent MR imaging. Besides T1- and T2-weighted sequences, short-tau-inversion-recovery sequences were used routinely. In 27 patients T1-weighted images after intravenous contrast injection were acquired additionally. As a control group the images of 15 patients without clinical signs for plantar fasciitis were evaluated.

RESULTS

In 25 of 28 cases (89%) the clinical diagnosis of plantar fasciitis was established by MR imaging. The most common finding was a peritendinous edema at the calcaneal insertion site which was found in all 25 patients. In 19 of 25 cases (76%) a bone marrow edema of the calcaneus was present. In 14 of 25 cases (56%) an intratendinous signal intensity increase of the plantar fascia could be observed which showed contrast enhancement in 12 cases. Compared to the control group (mean thickness 3.3 mm) the plantar fascia showed significant thickening in the 25 MR positive patients (mean thickness 6.72 mm).

DISCUSSION

Besides thickening of the plantar fascia and intratendinous signal intensity increase with contrast enhancement to some extent, bone marrow edema of the calcaneus and peritendinous edema close to the plantar fascia are characteristic signs of plantar fasciitis on MRI. Both signs can reliably be seen on STIR sequences only.

Assessment of hindfoot deformity by three-dimensional MRI in infant club foot

In 12 infants aged under 16 months with unilateral club foot we used MRI in association with multiplanar reconstruction to calculate the volume and principal axes of inertia of the bone and cartilaginous structures of the hindfoot. The volume of these structures in the club foot is about 20% smaller than that in the normal foot. The reduction in volume of the ossification centre of the talus (40%) is greater than that of the calcaneus (20%). The long axes of both the ossification centre and the cartilaginous anlage of the calcaneus are identical in normal and club feet. The long axis of the osseous nucleus of the talus of normal and club feet is medially rotated relative to the cartilaginous anlage, but the angle is greater in club feet (10 degrees v 14 degrees). The cartilaginous structure of the calcaneus is significantly medially rotated in club feet (15 degrees) relative to the bimalleolar axis. The cartilaginous anlage of the talus is medially rotated in both normal and club feet, but with a smaller angle for club feet (28 degrees v 38 degrees). This objective technique of measurement of the deformity may be of value preoperatively.

Acute and subacute changes in the ultrasound measurements of the calcaneus following intense exercise

The amount of exercise necessary to cause bone structural change in humans is unknown. We examined whether a single bout of intense exercise in vivo leads to acute and subacute changes in the physical properties of bone as measured by ultrasound. It was hypothesized that structural changes such as accumulation of fatigue microdamage would result in a decrease in velocity of sound (VOS) and broadband ultrasound attenuation (BUA) across the calcaneus. We performed a prospective cohort study in 111 (97 M, 14 F) entrants of the 1996 Melbourne marathon (42.3 km) and 28 (10 M, 18 F) nonrunning controls. Runners had a mean (SD) age of 45.3 +/- 11.4 years (range 20-75), had completed 15.2 +/- 17.3 prior marathons (0-88), and had been running regularly for 14.2 +/- 9.2 years (0.25-50). An ultrasound densitometer (Cuba Clinical, McCue) was used to measure VOS and BUA across the right calcaneus. Runners were tested on three occasions: 1-3 days prior to, immediately after (<2 hours), and 5-6 days following the marathon. Seventy-three (66%) runners presented for all three measurements. Controls were tested on three occasions with the same time intervals as the runners. BUA values in the runners were significantly elevated by 5.0% immediately after the marathon but returned to baseline levels by the third test session (P = 0. 0001). Changes in BUA values in the controls were not significant and all were less than 0.7% (P = 0.88). Age was a significant independent predictor of the BUA change between test 1 and test 2 in the runners (beta = 0.2094; SE = 0.0917; P = 0.03). VOS measurements were not significantly different across the three testing sessions in both the runners (P = 0.07) and the controls (P = 0.33). Therefore, ultrasound measurements of BUA and VOS did not detect evidence of lasting structural change in the calcaneus following a marathon.

Bone mineral assessments in the calcaneus after anterior cruciate ligament injury. An investigation of 92 male patients before and two years after reconstruction or revision surgery

The aim of this study was to assess the Bone Mineral Areal mass (BMA) in the calcaneus of male patients with unilateral anterior cruciate ligament (ACL) injury before and after reconstruction and to assess whether the BMA ratio or the BMA of the injured and uninjured side correlated with the level of activity, functional performance or the time period between the injury and the reconstruction. Ninety-two male patients with unilateral ACL injury were included in the study. The BMA was analysed immediately prior to surgery: a median of 11 (2-192) months after the injury in 30 patients aged 26 (15-41) years scheduled for primary ACL reconstruction (Group A). Forty-nine patients aged 29 (18-49) years had their BMA analysed a median of 24 (23-29) months after the primary ACL reconstruction (Group B). Thirteen patients aged 27 (21-39) years had their BMA analysed a median of 24 (20-45) months after ACL revision surgery (Group C). The median BMA ratio (injured side/uninjured side) was 96 (88-105)% in Group A, 96 (86-118)% in Group B and 95 (83-111)% in Group C. In all three groups, the median BMA value in the calcaneus was significantly lower on the injured side compared with the uninjured side (P=0.001, P=0.0003, P=0.01 in Groups A, B and C, respectively). The time period between the injury and the reconstruction neither correlated with the BMA ratio nor the BMA of the injured or the uninjured side in Group A. The level of activity as measured by the Tegner activity level and the functional performance as measured by the one-leg-hop quotient did not correlate with the BMA ratio in any of the groups. In the 49 patients with a primary ACL reconstruction (Group B), the post-operative Tegner activity level correlated with the BMA, on both the injured and uninjured side (P=0.0003, P=0.0005, respectively), when the BMA was assessed two years after the index operation. Male patients with unilateral ACL injury had a significantly lower BMA in the calcaneus on the injured side compared with the uninjured side before primary reconstruction, two years after primary reconstruction and two years after revision surgery. The time period between the injury and the index operation did not correlate with the BMA. A high level of activity correlated with the BMA on both the injured and the uninjured side two years after primary reconstruction.

Intra-articular calcaneal fractures: effect of open reduction and internal fixation on the contact characteristics of the subtalar joint

Intra-articular calcaneal fractures are associated with significant long-term morbidity, and considerable controversy exists regarding the optimum method of treating them. The contact characteristics in the intact subtalar joint were determined at known loads and for different positions of the ankle and subtalar joint, using pressure-sensitive film (Super Low; Fuji, Itochu Canada Ltd, Montreal, Quebec). We measured the contact area to joint area ratio (pressure > 5 kg force/cm2 [kgf/cm2]) which normalizes for differences in joint size and the ratio of high pressure zone (>20 kgf/cm2) as a reflection of overall increase in joint pressure. Three simulated fracture patterns were then created and stabilized with either 1 or 2 mm of articular incongruity. Eight specimens were prepared with a primary fracture line through the posterior facet, eight with a joint depression-type fracture, and six with a central joint depression fracture. A measure of 1 to 2 mm of incongruity in the posterior facet for all three fracture patterns produced significant unloading of the depressed fragment, with a redistribution of the overall pattern of pressure distribution to parts of the facet that were previously unloaded.

Operative management of Haglund's deformity in the nonathlete: a retrospective study

Haglund's deformity, or "pump bump," is a common cause of posterior heel pain. Management of the condition usually consists of nonoperative therapy. This study presents a retrospective study of 65 cases (53 patients), with symptomatic Haglund's deformity in nonathletes (13 male and 40 female), who presented during a 4-year period (1989-1994). Sixty-five percent (39 heels) of these patients failed to respond to nonoperative therapy for an average of 62 weeks, (range, 4-260 weeks). This group of patients went on to operative treatment. Surgical management consisted of excision of the posterior calcaneal tuberosity through a medial longitudinal incision with debridement, reattachment of the Achilles tendon using bone anchors, and 4 weeks of postoperative immobilization. Thirty-nine patients (74%) were contacted for follow-up. The average follow-up period for these patients was 155 weeks, (range, 92-335 weeks). There were 50% excellent results, 47% good results, 3% fair results (1 patient), and no poor results. The Maryland Foot Score for operated heels was an average of 67/100 preoperative and an average of 92/100 postoperative. On unoperated heels the score was an average of 81/100 at first evaluation and an average of 86/100 at final evaluation. Complications included one recurrence of painful prominence, one wound infection, and one incisional neuroma. The outcome of these cases demonstrated that in those patients who fail nonoperative treatment, surgical treatment of Haglund's deformity produces a predictably good surgical result when performed using the technique described.

[Computer-assisted structure analysis of trabecular bone in the diagnosis of osteoporosis]

Osteoporosis is characterized by reduced bone mass and a deterioration of bone structure which results in an increased fracture risk. The purpose of this review is to evaluate structure analysis techniques in the diagnosis of osteoporosis. Several imaging techniques were applied to analyze trabecular bone, such as conventional radiography, high-resolution computed tomography (HR-CT) and high-resolution magnetic resonance imaging (HR-MRI). The best results were obtained using high-resolution tomographic techniques. The highest spatial resolutions in vivo were achieved using HR-MRI. These studies show that texture parameters and bone mineral density predict bone strength and osteoporotic fractures in a complementary fashion. Combining both techniques yields the best results in the diagnosis of osteoporosis.

[Essential bone cyst of the calcaneus in children. Report of three cases]

OBJECTIVE

The purpose of this study was to analyze the properties of essential bone cyst of the calcaneus in childhood, as well as its evolution, and differences with regard to adults.

PATIENTS AND METHODS

The cases of children with a diagnosis of essential bone cyst of calcaneus in last sixteen years in the pediatric orthopedic unit of San Carlos Clinic have been reviewed. We evaluated the information regarding the clinical history and the radiological and histological date as well as the therapy result with esteroid intracavity therapy and curettage and bone grafting. The radiologic score was done following Södergard criteria and the posttreatment follow-up with Neer's score.

RESULTS

The mean age of the patients was 10.3 years. Two of the patients had recurrent heel pain for more than six months. Treatment consisted in intracavitary esteroid in two cases and curettage and bone grafting in all three cases, in two of the cases because of failure of esteroid therapy and in the other because of an atypical X-ray image. In all cases the histological stady identified the existence of a characteristic membrane conective tissue. The postsurgery follow-up a period of half four years has been satisfactory.

CONCLUSIONS

The essential bone cyst of the calcaneous is exceptional localization in children, frequently symptomatic and resistant to the esteroid intracavitaria contrary to what happens with the essential bone cyst of other localizations and with the essential bone cyst of the calcaneus in the adults. The recurrent heel pain and atipical X-ray image are surgery indications.

[Our method of treatment of dislocated fractures of the heel bone (preliminary report)]

The authors present first experience with their method of treatment of displaced fractures of calcaneus. The method is based on the combination of direct and indirect reposition of fragments and exact fixation with K-wires. Axial and AP X-ray and 2 plane CT scan are indispensible conditions for operation planning. The procedure can be divided into 4 phases: traction, elevation, compression, transfixation. Up till now 65 patients have been treated with this method. 20 patients with 24 fractures were evaluated according to the Creighton-Nebraska Health Foundation score in the interval 24 months after the operation. The average value of the score was 96.6 points, 16 patients were evaluated as excellent, in 2 patients the result was good.

Perimortem calcaneal and talar fractures sustained in a military air crash in Vietnam

The authors report on the skeletal elements of a minimum of 37 men who died in 1965 when their C-123 cargo airplane crashed into a mountainside in South Vietnam. Natural environmental processes reduced their bodies to skeletons; these osseous remains were recovered from the crash site nearly 10 years later. Among the remains were the calcanei and tali of at least 37 people. These bones, devoid of soft tissue, provide a rare opportunity to examine and document the pattern of perimortem fractures in multiple individuals who died in the same incident. This case also provides information on a range of variability of skeletal fractures that is unavailable in comparative skeletal collections, and that might be overlooked with radiography or during physical examination.

In vivo high resolution MRI of the calcaneus: differences in trabecular structure in osteoporosis patients

The purpose of this study was to use high resolution (HR) magnetic resonance (MR) images of the calcaneus to investigate the trabecular structure of patients with and without osteoporotic hip fractures and to compare these techniques with bone mineral density (BMD) in differentiating fracture and nonfracture patients. Axial and sagittal HR MR images of the calcaneus were obtained in 50 female (23 postmenopausal patients with osteoporotic hip fractures and 27 postmenopausal controls). A three-dimensional gradient-echo sequence was used with a slice thickness of 500 micron and in plane resolution of 195 x 195 micron. Texture analysis was performed using morphological features, analogous to standard histomorphometry and fractal dimension. Additionally, BMd measurements of the hip (dual-energy X-ray absorptiometry) were obtained in all patients. Significant differences between both patient groups were obtained using morphological parameters and fractal dimension as well as hip BMD (p < 0.05). Odds ratios for the texture parameters apparent (app.) bone volume/total volume and app. trabecular separation were higher than for hip BMD. Receiver operator characteristic values of texture measures and hip BMD were comparable. In conclusion, trabecular structure measures derived from HR MR images of the calcaneus can differentiate between postmenopausal women with and without osteoporotic hip fractures.