Intraosseous myolipoma of the calcaneus

A man in his 40s presented with an incidental finding of an osteolytic bone lesion. He sustained an ankle injury while inline skating, fracturing his lateral malleolus. Besides the fracture, radiographic imaging on the day of the injury incidentally revealed a well-defined solitary osteolytic lesion with a sclerotic rim within the right calcaneus. MRI showed an intraosseous, fat-containing lesion with focal contrast enhancement, assessed as an intraosseous lipoma with central necrosis. In the pathological analysis of a sample of the lesion an intraosseous myolipoma of the calcaneus was found-an unexpected and extraordinary finding. To prevent pathological fracturing, curettage and bone grafting were performed using autologous iliac crest bone in combination with allogenous bone chips.

Calcaneal Bone Biopsy Inconsistency between Specimens Obtained From Trephine and Fine Needle Biopsy Techniques

Standardized methods for osteomyelitis (OM) diagnosis of the lower extremity have proven to be difficult. Preoperative probability of foot osteomyelitis necessitates a combination of clinical, laboratory, imaging evidence (i.e., X-ray, CT, MRI), and bone biopsy to guide diagnosis and treatment. In the recent past, the relative weight that clinicians give to these collections of data to advise potential surgical intervention has been challenged, particularly with histologic evaluation of bone biopsy-traditionally considered "gold standard" in OM diagnosis. This study seeks to further expand this dialogue by retrospectively comparing calcaneal bone biopsies performed by direct visualization trephine approach (performed by Surgeons) vs fine needle biopsy with fluoroscopy guidance (performed by Interventional Radiologists). Results obtained from 57 patients with suspected calcaneal osteomyelitis demonstrate that Trephine obtained samples are significantly more likely to produce histopathologic evidence of OM (p-value: .013), microbiologic evidence of OM (p-value: <.001) and have better histopathologic and microbiologic concordance (p-value: <.001) than calcaneal bone biopsies obtained from Fine Needle Biopsy with fluoroscopy guidance.

Intraoperative cone-beam computed tomography-guided curettage for osteoid osteoma

Recently, cone-beam computed tomography (CBCT)-guided surgeries have been developed for bone and soft tissue tumors. The present study aimed to evaluate the efficacy of CBCT-guided curettage for osteoid osteoma. Our study population included 13 patients who underwent primary curettage for osteoid osteoma using intraoperative CBCT in a hybrid operating room between April 2019 and November 2022. We collected the following data: sex, age, follow-up period, symptom onset to time of surgery, tumor size and location, length of skin incision, operating time, radiation dose, recurrence, postoperative complications, and visual analog scale for pain during the last follow-up. There were 10 male and 3 female patients, and the mean age was 25.0 years (range, 9-49 years). The mean follow-up period was 10.6 months (range, 0.4-24.0 months). The locations of the tumors were the proximal femur in 6 patients, the acetabular region in 2 patients, and the ilium, tibial shaft, calcaneus, cuboid, and talus in 1 patient each. The mean time of symptoms onset to surgery was 18.7 months (range, 2.3-69.9 months). The mean maximum diameter of the tumor was 5.9 mm (range, 3.5-10.0 mm). The mean length of the skin incision was 2.2 cm (range, 1.5-3.5 cm). The mean operating time was 96.9 minutes (range, 64-157 minutes). The mean dose of radiation was 193.2 mGy (range, 16.3-484.0 mGy). No recurrences, postoperative complications, and reoperation were observed in this study. All the patients reported 0 mm on the visual analogue scale for pain on the last follow-up. CBCT-guided curettage for osteoid osteoma was minimally invasive and reliable. This procedure can be effective for the treatment of lesions found in deep locations such as the pelvic bone and proximal femur or an invisible lesion that cannot be detected by regular fluoroscopy.

Identification of a previously unreported site of subchondral bone injury in the dorsodistolateral calcaneus in Thoroughbred racehorses

BACKGROUND

Increasing accessibility and advancements in computed tomographic (CT) imaging improve understanding of the contributors to poor performance in the Thoroughbred racehorse.

OBJECTIVES

To characterise an unreported site of tarsal subchondral bone injury (SBI) in Thoroughbred racehorses.

STUDY DESIGN

Retrospective, cross-sectional analytical study.

METHODS

Tarsal CT scans of 108 horses were reviewed for evidence of SBI in the dorsodistolateral calcaneus (DDLC). Signalment, including age, breed, sex, and discipline of horses, was recorded. The association of DDLC SBI with Thoroughbred racehorse compared to other breeds/disciplines was calculated. Nuclear scintigraphic scans of the hindlimbs of Thoroughbreds between 2007 and 2022 were also reviewed for increased radiopharmaceutical uptake (IRU) suggestive of DDLC SBI.

RESULTS

Tarsal CT scans of 108 horses were analysed and lesion location and type were recorded. DDLC SBI was identified in 8/108 (7.3%) horses. All lesions were found in racing Thoroughbreds (Fischer's exact test p = 0.002) and in 20% (8/40) of racing Thoroughbreds that underwent tarsal CT. DDLC SBI was determined to be the primary cause of lameness in 3/8. Third tarsal bone fracture was considered the primary cause of lameness in 3/8 horses. A total of 1663 nuclear scintigraphic scans of 1603 Thoroughbred horses were reviewed. Increased IRU in the DDLC was present in 13 horses (0.9%).

MAIN LIMITATIONS

Study limitations include the retrospective nature of the study, incomplete medical records, lack of sensitivity/specificity data for lesion identification on various imaging modalities or comparison to histopathology, and limited substantive follow-up information.

CONCLUSIONS

The DDLC is a previously unreported site of SBI in the Thoroughbred racehorse. The lesion can be the primary source of lameness but may also be found in horses with other clinically relevant osseous injuries. This lesion may be underestimated in the Thoroughbred population. Further investigation is required to determine the true prevalence, clinical relevance, and prognosis in Thoroughbred racehorses with this injury.

Calcaneus as a Rare Location of Solitary Osteochondromas: Two Case Reports

Osteochondromas are the most common benign bone tumors, with an incidence of 36% to 41% among benign bone tumors. They can be caused by genetics, trauma, and growth defects. The incidence of all osteochondromas in the hands and feet is approximately 10%, and they are extremely rare in the calcaneus. They generally arise from the metaphysis and metaphyseal-diaphyseal region of the long bones. Osteochondromas, which are generally painless, are noted with signs of inflammation in the bursa, vascular and nerve compression, pain caused by joint deterioration, swelling in the subcutaneous tissue, or gait disturbance. The incidence of malignant transformation of solitary osteochondromas is 1%. We present two cases, an 11-year-old male patient and a 32-year-old male patient, diagnosed with osteochondroma in the calcaneus.

Limb salvage surgery for calcaneal chondrosarcoma: A case report

BACKGROUND

Limb salvage surgery for calcaneal sarcomas remains challenging due to its poor compartmentalization. While below-knee amputation is still the standard choice of operative treatment, total calcanectomy with or without reconstruction was advocated. This report aims to analyze the clinical outcome of calcaneal reconstruction with cement and replantation in situ after the inactivation of tumor.

METHODS

We describe a 73-year-old male patient who suffered chronic pain and increasingly larger neoplasm in the left foot for about 3 years. Based on the results of percutaneous biopsy, a diagnosis of chondrosarcoma was made.

RESULTS

The patient underwent total calcanectomy, inactivation of calcaneus tumor, and reconstruction with cement. The Achilles tendon was detached through a Cincinnati incision. No adverse events occurred both during and after the surgery. At the last follow-up of 29 months, the patient claimed no pain, no evident limp, or any limitation of daily activities. Image examination, weight-bearing test, and MSTS score revealed a satisfactory result.

CONCLUSION

Calcaneal reconstruction with bone cement after total calcanectomy, inactivation of calcaneus tumor, and replantation in situ is likely to provide a feasible surgical choice and a satisfactory clinical outcome.

Behavior during aging of bone-marrow fatty-acids profile in women's calcaneus to search for early potential osteoporotic biomarkers: a 1H-MR Spectroscopy study

AIM

Identify new potential biomarkers of osteoporosis at an early stage, by magnetic resonance spectroscopy (MRS), studying early changes in the metabolic profile of bone-marrow fatty acids in women's calcanei during healthy aging and osteoporosis status.

METHODS

Single voxel MRS was performed by using a point resolved spectroscopy (PRESS) sequence at 3T. Thirty-four Caucasian women (age range: 22-59 years) were recruited to investigate calcaneus bone marrow. The cohort was constituted of four groups according to age, menopausal status, and T-score evaluated after a DXA examination on the femoral neck. Women were classified in young control (n = 11, mean age = 26.5 ± 3.8 y, age range: 22-34 years), perimenopausal groups (n = 11, mean age = 42.0 ± 3.6 y, age range: 37-47 years), postmenopausal group (n = 9, mean age = 55.4 ± 2.9 y, age range: 50-59 years, mean T-score = -1.70 ± 0.50) and osteoporotic group (n = 6, mean age = 53.0 ± 2.8 y, age range: 50-58 years, mean T-score = -2.54 ± 0.10). The total lipid content (TL), the Unsaturation Index (UI), and the fraction of unsaturated/polyunsaturated fatty acid (f_UFA and f_PUFA) were calculated.

RESULTS

TL was significantly correlated with age (r = 0.73, p < 0.001). TL increases linearly with age in the young + perimenopausal population (r = 0.92, p < 0.001) but this trend is not significant in the postmenopausal subject (r = 0.48, p = 0.07). No significant correlation was found between T-Score and TL in postmenopausal and osteoporotic women, whereas a significant correlation was found between TL and time interval (t_p) between the age at menopause and the age of the subject at the MRS examination. Conversely, no correlation was found between T-score and t_p. The unsaturation index (UI) does not significantly discriminate between osteoporotic, peri- and postmenopausal women. On the other hand, f_UFA is significantly different in peri-menopausal and osteoporotic subjects (p = 0.02), while f_PUFA is significantly different both between peri- and postmenopausal women (p = 0.05) and postmenopausal and osteoporotic subjects (p = 0.03). Both f_UFA and f_PUFA did not correlate with subjects' age.

CONCLUSION

In the female calcaneus, f_UFA and f_PUFA are promising measurable quantities for the characterization of bone marrow's composition potentially correlated with the development of osteoporosis, whereas UI does not differentiate between subjects of varying osteoporotic status. The fact that the TL in the calcaneus is correlated with t_p, indicates that active metabolic changes are still occurring in these subjects, giving complementary information to the DXA about the changes in bone marrow's composition which may affect the whole bone health.

INCIDENTAL INTRAOSSEOUS CALCANEAL LIPOMA IN A PATIENT SUFFERING FROM PLANTARFASZIITIS

Intraosseous calcaneal lipoma is a rare benign bone tumor. The incidence of intraosseous lipoma involving the calcaneus has been noted to account for fewer than 8-15% of all intraosseous lipoma. The etiology of the lesion is unknown. A post-traumatic secondary bone reaction, healing bone infarct, and benign neoplasm have been discussed. The symptoms can be nonspecific, varying from dull, intermittent pain to activity-related plantar pain. This pain can predictably be misdiagnosed as plantar fasciitis. We present the case of a 49-year-old male patient suffering from plantar fasciitis for three months and incidental asymptomatic intraosseous calcaneal lipoma, which was diagnosed by x-ray and CT scan. As the patient was out of complaints, the typical CT findings we saw no indication for biopsy but recommended regular CT and MRI controls.;

Arthroscopic Management of Giant Cell Tumor of the Calcaneus

Giant cell tumor of the calcaneal bone is a very rare entity and generally seen in the 30 to 40 years age group. We report a case of a 17-year-old male with giant cell tumor of the calcaneus, presented with left heel pain without another obvious physical abnormality. Radiographs showed a lobulated, well-defined, lytic lesion of the calcaneus with narrow transitional zone without periosteal reaction, no extraosseal spread, and no lung metastases. Arthroscopic procedure was done directly for both diagnostic and curative procedures. All soft, grayish lesions were completely removed arthroscopically using direct lateral portals and the suspected reactive zones debrided using high-speed burr and injected with corticosteroid. Histopathology confirmed the suspected diagnosis. The postoperative clinical course was uneventful with immediate pain relief and full weight bearing and movement allowed soon. The patient had no recurrent pain as well as recurrent radiographic lesions, and normal joint mobility 9 months postoperatively. Considering the accessibility of the lesion, giant cell tumor of the calcaneal bone can be successfully treated arthroscopically using direct lateral approach.Levels of Evidence: Therapeutic, Level IV: Retrospective, case report.

Long-term survival following radiofrequency ablation of lung metastases in an elderly patient with calcaneal osteosarcoma: A case report and review of the literature

RATIONALE

Recently, the number of osteosarcomas has been increasing in elderly patients due to human longevity. Lung metastases are the primary cause of death from osteosarcomas. Complete resection of lung metastases can prolong the survival. However, complete resection in elderly patients is often difficult due to high risk of operative complications. Computed tomography (CT) guided radiofrequency ablation (RFA) is a minimally invasive technique to destroy tumor nodules using heat. In this report, we present the first case older than 65 years applying RFA for lung metastases due to osteosarcoma.

PATIENT CONCERNS

A 74-year-old male presented with 1-year history of heel pain. A conventional high-grade osteosarcoma in his calcaneus was diagnosed. Below-knee amputation was performed. However, lung metastases were found in both lungs 1 year after amputation. CT-guided lung RFA was chosen since surgical intervention for lung metastases was abandoned because of tumor multiplicity and medical comorbidities. A total of 18 lung metastases were treated by CT-guided RFA. The most frequent complication was pneumothoraxes in 4 of 8 (50%) procedures and chest tube drainage was required in 2 of these (2 of 8 (25%) procedures).

DIAGNOSES

Six lung metastases of osteosaroma were found in both lungs at 1 year after surgery.

INTERVENTIONS

CT-guided lung RFA was performed. A total of 18 lung metastases were treated in 8 lung RF procedures.

OUTCOMES

The patient has been alive with disease for 5.5 years after the initial surgery.

LESSONS

CT-guided lung RFA is effective for elderly patients with osteosarcoma lung metastases in spite of discouragement of lung metastasectomy due to multiplicity of metastases and medical-comorbidities.

Brodie's abscess of the calcaneus in an adult patient

Brodie's abscess of the calcaneus is an uncommon benign lesion that has rarely been reported in the literature. This study presents a rare case of a Brodie's abscess of the calcaneus caused by Staphylococcus aureus in an adult patient. A 46-year-old immunocompetent man had undergone nonsurgical treatment since childhood owing to the diagnosis of a heel spur. Radiological evaluation revealed a benign radiolucent cystic lesion of the calcaneus surrounded by a sclerotic rim. This condition was accompanied by perilesional bone marrow edema. Thereafter, surgical treatment was planned. During surgery, the content of the lesion was observed to be purulent. Meticulous intralesional debridement was performed, and antibiotic-loaded bone cement beads were placed. Subsequent to microbiological and pathological examinations, the cystic lesion was confirmed to be a Brodie abscess; however, direct clinical evidence of an intraosseous infection was lacking. The patient was followed up for 14 months with no complications until recovery. A Brodie abscess may mimic bone tumors. The onset of a Brodie abscess is insidious, and the clinical findings of such lesions may be obscure. A Brodie abscess of the calcaneus should be considered in the differential diagnosis of patients with chronic heel pain when suspicious radiological findings are evident.

Calcaneal Ultrasound and Its Relation to Dietary and Lifestyle Factors, Anthropometry, and Vitamin D Deficiency in Young Medical Students

BACKGROUND

Bone quality and peak bone mass are greatly affected by lifestyle factors. The objective of the study was to investigate the relationships between anthropometry, dietary and caloric intake, body composition measurements, physical activity, and vitamin D status with quantitative ultrasound-based bone parameters among medical students.

METHODS

Both male and female medical college students were included in this study. A detailed questionnaire was administered, collecting clinical, dietary, physical activity information, physical examination details, including body mass index (BMI). Body composition (total body fat, total body water, muscle mass, mean visceral fat mass, basal metabolic rate, bone mass using a bioelectrical impedance analyzer) and calcaneal heel ultrasound parameters were measured using an Osteosys Sonost-3000, Ultrasound Bone Densitometer were measured, respectively.

RESULTS

In this cross-sectional study, 211 healthy students with a mean age of 20.1 ± 1.1 years, 51.7% (n = 109) were males. Majority (79.4%) of the young adults had vitamin D deficiency. The mean BMI, calcium intake, and vitamin D levels were 22.35 ± 3.43 kg/m², 788.7 ± 364.8 mg/day, and 15.02 ± 8.63 ng/ml, respectively. Female subjects compared to males had statistically significantly lower daily energy intake, muscle mass, visceral fat mass, calcium intake, and vitamin D levels. In addition the median Z-scores in females [-1.40 (-0.57 to -1.82)] was significantly poorer than the male [-0.50 (0.20 to -1.3)] counterparts, p-value <0.001. Multiple regression analysis showed that overall body fat percent (p-value 0.016) and visceral fat percent (p-value 0.029) were the only significant negative predictors to the calcaneal bone quality index (BQI) values.

CONCLUSION

Adolescent lifestyle patterns can influence young adult bone strength. The young Pakistani females exhibited significantly lower dietary intakes and more inadequate bone parameters compared to males. Our data suggest that total body and visceral fat percent are the predominant negatively associated determinant of bone strength for this cohort. Calcaneal ultrasound can be utilized for mass screening of young adults for identification of low BMD.

Solitary Plasmacytoma of the Calcaneum: A Case Report

Solitary Plasmacytoma is characterized by a mass of neoplastic monoclonal plasma cells in either bone or soft tissue without evidence of systemic disease attributing to myeloma. Solitary bony plasmacytoma commonly presents in the axial skeleton. The occurrence of solitary bony plasmacytoma in young individuals is exceedingly rare but has been reported sporadically. We report a case of Solitary bony plasmacytoma involving the calcaneum (appendicular skeleton) in a 26-year-old male with a prior history of trauma at the same site. To our knowledge, this is one of the few cases of solitary bony plasmacytoma in the calcaneum being reported. Our patient presents with some unusual features like the unusual site of the lesion (calcaneum), presentation at a young age and the disease being symptomatic following trauma.

Foot binding in a Ming dynasty cemetery near Xi'an, China

This paper describes the morphology of the feet of a population of elite women from the Ming dynasty (1368-1644 CE) in Shaanxi province. This is a social stratum, time, and place in which foot binding was practiced. Among a group of 31 skeletons exhumed from the cemetery, eight were women with well-preserved foot bones. Macroscopic examination revealed that half these women (4/8) had clearly altered foot bones: the metatarsal bones, and the few observable phalanges, were gracile and small, while the tarsal bones exhibited a slight reduction in size but no dramatic change in morphology. The other half of the women (4/8) had apparently unmodified metatarsal bones. T-tests comparing linear measurements of the foot bones between the two groups revealed that metatarsal bones were the most affected by binding, and among the tarsal bones, the talar trochlea and calcaneal dimensions were most impacted. This small group of skeletons reveals that some elite women in Shaanxi apparently still did not practice foot binding in the late Ming dynasty, or practiced a much milder form of foot binding, and that there was considerable variation even among those who did practice it.

Endoscopic resection of symptomatic os calcaneus secundarius

Os calcaneus secundarius is an accessory ossicle resulting from a secondary ossification center of the anterior facet of the calcaneus. It may cause chronic pain and limitation in inversion motion after inversion ankle sprain. Excision of the ossicle is indicated if the symptoms do not resolve with conservative treatment. A case of symptomatic os calcaneus secundarius, which was successfully resected endoscopically, is presented.

Single stage treatment of diabetic calcaneal osteomyelitis with an absorbable gentamicin-loaded calcium sulphate/hydroxyapatite biocomposite: The Silo technique

BACKGROUND

Chronic osteomyelitis necessities appropriate infected bone and soft tissue excision. The authors describe the Silo surgical technique for the treatment of calcaneal osteomyelitis using a new antibiotic-loaded absorbable calcium sulphate/hydroxyapatite biocomposite.

METHODS

The Silo method involves debridement of the dead bone and local delivery of antibiotic in drilled tunnels using the biocomposite. It is combined with multiple sampling and culture-specific systemic antibiotic treatment guided by a multidisciplinary team. Twelve consecutive diabetic patients with heel ulcers and calcaneal osteomyelitis were treated with the above method. All had comorbidities (Cierny-Mader (C-M) Class B hosts). The mean age was 68 years (range 50-85). A retrospective review of radiographs and electronic medical records was conducted.

RESULTS

Patients were followed up until clinical cure of the ulcer for a mean of 16 weeks (range 12-18). Infection was eradicated in all 12 patients with a single stage procedure following a bone preserving technique. One patient required a subsequent flap operation and six vacuum-assisted closure (V.A.C.). There was also one case of prolonged wound leakage and no calcaneal fractures.

CONCLUSIONS

The Silo technique is an effective method of local delivery of antibiotics and can be effectively implemented into the single-stage treatment of calcaneal osteomyelitis offering increased bone preservation and local delivery of antibiotic, decreasing the need for a major amputation.

LEVEL OF EVIDENCE

Level IV- case series.

Fully automated determination of arch angle on weight-bearing foot radiograph

BACKGROUND AND OBJECTIVE

Flatfeet can be evaluated by measuring the calcaneal-fifth metatarsal angle on a weight-bearing lateral foot radiograph. This study aimed to develop an automated method for determining the calcaneal-fifth metatarsal angle on weight-bearing lateral foot radiograph.

METHOD

The proposed method comprises four processing steps: (1) identification of the regions including the calcaneus and fifth metatarsal bones in a foot image; (2) delineation of the contours of the calcaneus and the fifth metatarsal; (3) determination of the tangential lines of the two bones from the contours; and (4) determination of the calcaneal-fifth metatarsal angle between the two tangential lines as arch angle.

RESULTS

The proposed method was evaluated using 300 weight-bearing lateral foot radiographs. The arch angles determined by the proposed method were compared with those measured by a radiologist, and the errors between the automatically and manually determined angles were used to evaluate the precision of the method. The average error in the proposed method was found to be 1.12° ± 1.57° In the study, in 73.33% of the cases, the arch angles could be determined automatically without redrawing any tangential lines; in 23.00% of the cases, the angles would be correctly determined by redrawing one of the tangential lines; further, in only 3.67% of the cases, both the calcaneal and fifth metatarsal tangential lines needed to be redrawn to determine the arch angles.

CONCLUSION

The results revealed that the proposed method has potential for assisting doctors in measuring the arch angles on weight-bearing lateral foot radiographs more efficiently.

[Arthroscopic Treatment of Chronic Retrocalcaneal Bursitis - Endoscopic Calcaneoplasty]

INTRODUCTION The authors evaluate the results of endoscopic treatment and analyse the causes of persisting difficulties in retrocalcaneal bursitis unresponsive to conservative treatment. Stated as one of the causes is the possible chronic irritation of minor/partial tears of anterior parts of the distal portion of the Achilles tendon, which have no chance to heal due to continued overload and impingement syndrome of the superior prominence of the calcaneal tubercle. MATERIAL AND METHODS The authors evaluate the group of 24 patients (10 women and 14 men) diagnosed with retrocalcaneal bursitis, who reported more than 12 months of difficulties and in whom the conservative therapy options have already been exhausted. The decision to perform a revision arthroscopy was made by the authors based on chronic long-lasting difficulties, clinical examination, calcaneus radiograph, ultrasound examination and negative response to the performed conservative treatment. The MRI scan was obtained in 4 patients. In 11 patients during arthroscopy the Achilles tendon was intact, in 13 patients (54.2%) minor tears were detected on the anterior aspect of the distal Achilles tendon, not diagnosed preoperatively (by ultrasound examination). In all the patients, resection of the prominence of the calcaneal tubercle was performed, whereas in patients with affected Achilles tendon also the loose tendon fragments were resected. RESULTS A total of 23 patients reported an improvement of their condition, the pain subsided at 21-43 days. Altogether 21 patients returned to activities carried out before the onset of pain. The AOFAS score values measured preoperatively in patients with an intact tendon were 59.5 ± 15.0, in patients with an injured tendon it was 45.57 ± 9.6, while 6 months after the surgery the values were 95.7 ± 6.2, or 88.71 ± 7.8 respectively. In 1 female patient, with one prior surgery, diagnosed with a partial tear of the Achilles tendon, the effect of the surgery was unsatisfactory. After six months the patient underwent an open revision surgery and the Achilles tendon reinsertion. No intraoperative or postoperative complications were observed. DISCUSSION The endoscopic technique facilitates a more visible bone resection, with better control of resection, which is less invasive than the open technique. The source of irritation can be removed, which is not always only the prominence of the calcaneal tubercle, but another cause of persisting problems can also be a microtrauma affecting the anterior portion of the Achilles tendon, with a reactive hyperaemia in bursal tissue. Compared to literature and also based on the results of the authors of this retrospective study, the endoscopic calcaneoplasty is less invasive than the open surgery. It is always necessary to properly diagnose the causes of difficulties and to timely respond to persisting symptoms in patients, not responding satisfactorily to conservative therapy. CONCLUSIONS The findings presented by the authors provide a new perspective on the causes of chronic problems such as the "posterior heel pain" and tend to give preference to the active endoscopic approach in patients with persisting problems, not responding to conservative treatment, predisposed based on the radiological examination and with a positive finding on ultrasound or MRI scan. Key words:retrocalcaneal bursitis, endoscopic calcaneoplasty, arthroscopy.

Remodeling of the Calcaneocuboid Joint in the Acquired Flatfoot

There has been debate recently as to whether the lateral column is actually short in the acquired flatfoot. Doubters argue that it is not possible for the lateral column to change in length and actually shorten, especially in the acquired type. In this series of 21 consecutive patients operated on for an acquired flatfoot, the calcaneocuboid joint (CC) had remodeled in all, resulting in the calcaneal side being short, facing laterally and dorsally. These findings give evidence to the rationale for performing a lateral column lengthening (LCL) proximal to the CC joint to treat the acquired flatfoot. When performing a LCL, one should attempt to restore length to the calcaneal side of the joint and to redirect it medially and plantarward. (Journal of Surgical Orthopaedic Advances 27(3):237-245, 2018).

Immobilization-induced osteolysis and recovery in neuropathic foot impairments

BACKGROUND

Neuropathic foot impairments treated with immobilization and off-loading result in osteolysis. In order to prescribe and optimize rehabilitation programs after immobilization we need to understand the magnitude of pedal osteolysis after immobilization and the time course for recovery.

OBJECTIVE

To determine differences in a) foot skin temperature; b) calcaneal bone mineral density (BMD) after immobilization; c) calcaneal BMD after 33-53weeks of recovery; and d) percent of feet classified as osteopenic or osteoporotic after recovery in participants with neuropathic plantar ulcers (NPU) compared to Charcot neuroarthropathy (CNA).

METHODS

Fifty-five participants with peripheral neuropathy were studied. Twenty-eight participants had NPU and 27 participants had CNA. Bilateral foot skin temperature was assessed before immobilization and bilateral calcaneal BMD was assessed before immobilization, after immobilization and after recovery using quantitative ultrasonometry.

RESULTS

Before immobilization, skin temperature differences in CNA between their index and contralateral foot were markedly higher than NPU feet (3.0 degree C versus 0.7 degree C, respectively, p<0.01); BMD in NPU immobilized feet averaged 486±136mg/cm², and CNA immobilized feet averaged 456±138mg/cm², p>0.05). After immobilization, index NPU feet lost 27mg/cm²; CNA feet lost 47mg/cm² of BMD, p<0.05. After recovery, 61% of NPU index feet and 84% of CNA index feet were classified as osteopenic or osteoporotic.

CONCLUSIONS

There was a greater osteolysis after immobilization with an attenuated recovery in CNA feet compared to NPU feet. The attenuated recovery of pedal BMD in CNA feet resulted in a greater percentage of feet classified as osteoporotic and osteopenic.

Identification of 153 new loci associated with heel bone mineral density and functional involvement of GPC6 in osteoporosis

Osteoporosis is a common disease diagnosed primarily by measurement of bone mineral density (BMD). We undertook a genome-wide association study (GWAS) in 142,487 individuals from the UK Biobank to identify loci associated with BMD as estimated by quantitative ultrasound of the heel. We identified 307 conditionally independent single-nucleotide polymorphisms (SNPs) that attained genome-wide significance at 203 loci, explaining approximately 12% of the phenotypic variance. These included 153 previously unreported loci, and several rare variants with large effect sizes. To investigate the underlying mechanisms, we undertook (1) bioinformatic, functional genomic annotation and human osteoblast expression studies; (2) gene-function prediction; (3) skeletal phenotyping of 120 knockout mice with deletions of genes adjacent to lead independent SNPs; and (4) analysis of gene expression in mouse osteoblasts, osteocytes and osteoclasts. The results implicate GPC6 as a novel determinant of BMD, and also identify abnormal skeletal phenotypes in knockout mice associated with a further 100 prioritized genes.

Mycobacterium abscessus Osteomyelitis of the Calcaneus Presenting as Tumor-Mimicking Lesions: A Case Report

CASE

We present the case of a 51-year-old immunocompetent man with refractory heel pain who initially had been treated for plantar fasciitis. However, the pain was proven to be caused by a Mycobacterium abscessus infection of the calcaneus. The process of diagnosis and treatment is described.

CONCLUSION

Although rare, chronic heel pain can be caused by an atypical mycobacterial infection of the calcaneus. Because of its indolent clinical course, misdiagnosis is not uncommon with calcaneal osteomyelitis. Physicians should note that this rare infection should be considered in patients with refractory heel pain.

A rare probable chondroblastoma of the calcaneus in a pre-Columbian subadult from Illinois

Discrete cystic or tumorous intraosseous lesions can arise from a variety of benign and malignant conditions as well as trauma and infection. They are clinically rarely observed in the calcaneus. A fourteen-to-seventeen-year-old subadult recovered from a Late Woodland (∼AD 800-1100) period mortuary context in the Mississippi River Valley of central Illinois presents with a single lytic intraosseous lesion on the posterior right calcaneus that bilaterally perforates the cortex. The lesion, although primarily anterior to the epiphyseal plate, does breach it. There is also a small perforation of the outer cortex of the epiphysis above the insertion of the Achilles' tendon. The lesion is well-defined with a primarily spongy cancellous interior margin. On the body of the calcaneus, there is periostosis and a slightly expansive endosteal reaction. Comparative radiographic assessments undertaken to differentially diagnose the lesion indicate that it was likely not malignant. Based on the posterior location, the radiographic signature, the bilateral cortical perforation and the breach of the epiphysis, the lesion is best interpreted as a chondroblastoma.

Unicameral bone cyst of the calcaneus - minimally invasive endoscopic surgical treatment. Case report

The role of arthroscopic surgery for the treatment of various orthopedic pathologies has greatly improved during the last years. Recent publications showed that benign bone lesion may benefit from this minimally invasive surgical method, in order to minimize the invasiveness and the period of immobilization and to increase visualization. Unicameral bone cysts may be adequately treated by minimally invasive endoscopic surgery. The purpose of the current paper is to present the case report of a patient with a unicameral bone cyst of the calcaneus that underwent endoscopically assisted treatment with curettage and bone grafting with allograft from a bone bank, with emphasis on the surgical technique. Unicameral bone cyst is a benign bone lesion, which can be adequately treated by endoscopic curettage and percutaneous injection of morselized bone allograft in symptomatic patients.

Transformation of Benign Giant Cell Tumor of Bone Into Epithelioid Angiosarcoma

In this article, we report a case of transformation of a benign giant cell tumor (GCT) of the calcaneus into an epithelioid angiosarcoma. The patient presented to our service in 2003 and was followed until 2014. Transformation occurred 11 years after curettage, cryotherapy, cementation, and a well-documented disease-free interval. Longitudinal radiographs, magnetic resonance imaging, and histopathology were evaluated by the same medical team. There are only a few case reports and case series of malignancy associated with GCT of bone. To our knowledge, this case report is the first to describe an assessment of the transformation of a benign GCT of bone into an epithelioid angiosarcoma. Orthopedic surgeons, radiologists, oncologists, and pathologists should be aware of the potential for transformation of benign GCTs to high-grade sarcomas after a long disease-free interval.