Osteoporos Int DOI 10.1007/s00198-015-3111-4
CASE REPORT
A tuber calcanei avulsion fracture developed on the basis of idiopathic osteoporosis in a young male: a case report R. Terzi 1 & T. Özer 2
Received: 29 January 2015 / Accepted: 17 March 2015 # International Osteoporosis Foundation and National Osteoporosis Foundation 2015
Abstract Calcaneus fractures constitute 1.2 % of all fractures. Tuber calcanei avulsion fractures constitute 1.3–2.7 % of calcaneus fractures. Osteoporosis, osteomalacia, and diabetes mellitus have been reported to increase the risk of development of these fractures. It has been reported that tuber calcanei avulsion fractures in elderly females might develop due to osteoporosis. As far as we know, no tuber calcanei avulsion fracture developing on the basis of osteoporosis without presence of a trauma has been reported in young males in the literature. In the current case report, a 41-yearold male patient who was admitted with complaints of pain in the left heel and diagnosed with calcaneal avulsion fracture that developed on the basis of idiopathic osteoporosis and who was treated with conservative methods was presented. Keywords Avulsion fractures . Calcaneus fractures . Idiopathic male osteoporosis . Osteoporosis
Introduction Fractures that develop as a result of the detachment of a small part of the bony structure from the main bone at the site of attachment of the ligament or tendon to the bone following a strong muscle contraction are known as avulsion fractures. Avulsion fractures generally develop following a trauma or a
* R. Terzi [email protected] 1
Department of Physical Medicine and Rehabilitation, Kocaeli Derince Education and Research Hospital, Derince, Kocaeli, Turkey
2
Department of Radiology, Kocaeli Derince Education and Research Hospital, Derince, Kocaeli, Turkey
forced activity [1]. It is frequently observed in athletes [2], dancers [3], and children [4]. It has been reported in the literature that the most common regions in which avulsion fractures develop are pelvis [2], tibia [5], metatarsals [6], and calcaneus [7]. Calcaneus fractures constitute 1.2 % of all fractures. Tuber calcanei avulsion fractures constitute 1.3–2.7 % of calcaneus fractures [8]. In the literature, osteoporosis, osteomalacia, diabetes mellitus, peripheral neuropathy, and long-term immunosuppressive therapy have been reported to increase the risk of development of these fractures [9–11]. It has been reported that tuber calcanei avulsion fractures in elderly females might develop due to osteoporosis [12, 13]. As far as we know, no tuber calcanei avulsion fracture developing on the basis of osteoporosis without presence of a trauma has been reported in young males in the literature. In the current case report, a 41-year-old male patient who was admitted with complaints of pain in the left heel and diagnosed with calcaneal avulsion fracture that developed on the basis of idiopathic osteoporosis and who was treated with conservative methods was presented.
Case A 41-year-old male patient was admitted to our clinic with complaints of pain in the left heel. He stated that he had pain for approximately 2 weeks, and pain increases with loading. The patient’s medical history revealed that he had been diagnosed in another center with soft tissue injury, and nonsteroidal anti-inflammatory drugs and cold application had been recommended. There was no previous history of trauma in the patient. He stated that he had been working in the automotive sector and approximately 1 month prior, he changed departments, and in the new department that he works, he had
Osteoporos Int
to remain standing. There was no history of chronic disease or cigarette and alcohol use. Upon physical examination, there was tenderness on compression at the site of attachment of the Achilles tendon in the left heel and minimal edema in the heel. The foot ankle joint mobility was normal, but there was pain during ankle dorsiflexion. Upon physical examination, no skeletal system deformity was observed. The left foot roentgenogram was normal, except increased ray transmission (Fig. 1). In T1- and T2-weighted images on magnetic resonance imaging, an oblique hypointense fracture line and signal change consistent with an avulsion fracture were observed at the site of attachment of the Achilles tendon to the calcaneal tubercle (Fig. 2). As the patient had a calcaneal fracture without trauma and as he had increased ray transmission on the foot roentgenogram, bone mineral density was evaluated. Dual energy X-ray absorptiometry (DEXA) revealed a lumbar 1– 4 Z-score of −3.2, T-score of -3.2, and BMD 0.728 and a femoral Z-score of −1.7, T-score of −1.9, and BMD 0.736. It was thought that the avulsion fracture might have developed on the basis of osteoporosis. On laboratory tests that were conducted to determine the etiology of osteoporosis, fasting blood glucose, urea, creatinine, ALP, total protein, calcium, phosphor, PTH, and TSH were 81 mg/dl, 21 mg/dl, 0.81 mg/dl, 80 U/L, 7.7 gr/dl, 10 mg/dl, 2.7 mg/dl, 53 pg/ml, and 1.2 ng/ml, respectively. Calcium and phosphor in the 24-h urine sample were 207 and 699 mg/day, respectively. Testosterone, cortisol, FSH, LH, and ACTH were 7.4 ng/ml, 12.1 μg, 4.6 micU/ml, 4 micU/ml, and 52 pg/ml, respectively. Anti-endomisium antibody was negative, osteocalcin was 3.4 ng/ml, Beta-CTx was 0.2 ng/ml, sedimentation rate was 2 mm/h, CRP was negative, and hemogram was normal; 25 (OH) vitamin D3 levels were 17 ng/ml. Secondary causes of osteoporosis were excluded, and the patient was diagnosed with idiopathic male osteoporosis. For vitamin D deficiency, vitamin D at a dose of 50,000 IU/week was administered for 6 weeks, calcium was administered at a dose of 800 mg/day, and analgesic treatment (paracetamol 2000 mg/day) was regulated. He
Fig. 2 T1-weighted (a) and fat suppression T2-weighted (b) MR sections of the foot that were obtained in the sagittal plane. Hypointense fracture line in oblique course in calcaneal tubercle (arrow) and a signal increase consistent with bone marrow edema in fractured bone that does not demonstrate complete separation in the T2A section (b)
was consulted by the orthopedics and traumatology department. A short foot plaster was applied, and immobilization was recommended. At the end of 6 weeks, the fracture was completely healed, and the pain regressed almost completely. Joint mobility and isometric exercises were recommended, and he was followed-up. Seventy mg/week alendronate was prescribed for osteoporosis treatment.
Discussion
Fig. 1 Direct roentgenogram of the patient. No pathology was observed in calcaneal tubercle except slight loss of density
Tuber calcanei avulsion fractures are rarely observed extraarticular injuries [8]. The diagnosis depends on clinical suspicion, detailed history, physical examination, and imaging methods. Generally, it could be confused with similar clinical conditions such as foot sprains [14]. It was learned that the patient had had a different diagnosis in his first evaluation.
Osteoporos Int
Sudden and forceful dorsiflexion of the foot in the plantar flexion position, sudden contraction of triceps surae muscle during knee extension or direct trauma to the heel are thought to be responsible for the development of tuber calcanei avulsion fractures [14]. The patient had no previous history of trauma. He had stated that his working conditions changed approximately 1 month prior. We know that stress fractures develop as a result of injuries developing due to repeated use that exceeds the bone’s individual repair capacity [15]. As the working conditions of the patient became heavier, this might have triggered fracture development based on osteoporosis. Lee et al. [14] classified tuber calcanei avulsion fractures in four categories. According to this, type 1 is simple extraarticular type, type 2 is oblique fracture defined as beak fracture, type 3 is infrabursal avulsion fracture, type 4 is defined as a beak fracture in the shape of a small triangle fragment including deep fibers of the Achilles tendon. It has been reported that type 1 fractures in particular are related to osteoporotic failure fractures and are generally observed with minor trauma and in elderly individuals [8], whereas other types of fractures are commonly observed in younger males [14]. On MR imaging of the present case, an avulsion fracture was observed, which does not demonstrate a complete separation in calcaneal tubercle at the site of the attachment of the deep fibers of the Achilles tendon. According to this, the present case was evaluated as a type 4 calcaneal avulsion fracture that developed on the basis of osteoporosis without the presence of a trauma. The young age of the patient is its interesting feature. It has been reported that the calcaneal fractures that develop on the basis of osteoporosis are more frequently observed in females in their seventh decades [11, 16]. Generally, as osteoporosis is not thought to develop in young males, it could be overlooked [16]. Especially young males in which these types of fractures are detected without the presence of a trauma should be evaluated in terms of osteoporosis. These patients should be evaluated in terms of the secondary causes of osteoporosis, such as hypogonadism, glucocorticoid excess, alcoholism, gastrointestinal diseases, hypercalciuria, cigarette smoking, chronic anticonvulsant use, immobilization, osteogenesis imperfecta, homocystinuria, neoplastic diseases, rheumatoid arthritis, hyperthyroidism, and hyperparathyroidism [17]. In the present patient, no secondary cause of osteoporosis was found and he was diagnosed with idiopathic male osteoporosis. Osteoblast dysfunction or reduction in IGF-1 levels is found to be responsible for the etiology of idiopathic male osteoporosis [18]. In the literature, no clinical or laboratory etiological factors could be detected in approximately 40 % of male osteoporosis [19]. In the laboratory findings of the patient, only 25 (OH) vitamin D levels were found to be low. In their study that has been conducted in males with idiopathic osteoporosis, Al-Oanzi ZH et al. [20] found significantly high levels of D vitamin binding protein and significantly low levels of free plasma 25(OH) Vitamin D levels.
The treatment of calcaneal avulsion fractures change according to age, functional status, and level of separation of bony fragment. It has been reported that favorable results could be obtained through treatment with functional boats or plaster at equine position in non-separated fractures or fractures which are separated less than 1 cm [21]. Surgical techniques including various internal fixation methods should be preferred in fractures that are separated more than 1 cm [16]. Loading should be limited for 8–12 weeks [22]. In the present patient, successful treatment was achieved with conservative methods. Avulsion fractures that develop on the basis of osteoporosis could be observed not only in the elderly, but also in young male individuals. These patients should be evaluated in terms of osteoporosis.
Conflict of interest None.
References 1.
2.
3.
4.
5.
6.
7.
8.
9. 10.
11. 12.
Rotman J, Loftus M, Bartolotta R (2014) Avulsion fractures in the foot: telltale radiographic signs to avoid mismanagement. Clin Imaging. doi:10.1016/j.clinimag.2014.11.015 Osbahr DC, Chalmers PN, Frank JS et al (2010) Acute, avulsion fractures of the medial epicondyle while throwing in youth baseball players: a variant of Little League elbow. Shoulder Elb Surg 19(7): 951–7. doi:10.1016/j.jse.2010.04.038 Quarrier NF, Wightman AB (1998) A ballet dancer with chronic hip pain due to a lesser trochanter bony avulsion: the challenge of a differential diagnosis. J Orthop Sports Phys Ther 28(3):168–73 Tudisco C, Giovarruscio R, Febo A et al (2010) Intercondylar eminence avulsion fracture in children: long-term follow-up of 14 cases at the end of skeletal growth. J Pediatr Orthop B 19(5):403– 8. doi:10.1097/BPB.0b013e32833a5f4d Hayashi S, Nishiyama T, Fujishiro T et al (2011) Avulsion-fracture of the anterior superior iliac spine with meralgia paresthetica: a case report. J Orthop Surg (Hong Kong) 19(3):384–5 Lambers K, Ring D (2011) Elbow fracture-dislocation with triceps avulsion: report of 2 cases. J Hand Surg [Am] 36(4):625–7. doi:10. 1016/j.jhsa.2010.12.027 Shahid MK, Punwar S, Boulind C et al (2013) Aircast walking boot and below-knee walking cast for avulsion fractures of the base of the fifth metatarsal: a comparative cohort study. Foot Ankle Int 34(1):75–9. doi:10.1177/1071100712460197 Radzilani M, D’Alton E, Golele RG (2010) Avulsion fracture of the calcaneal tuberosity: a soft tissue complication from delayed treatment. Foot Ankle Online J 3:1 Hedlund L, Maki D (1998) Calcaneal fractures in diabetic patients. J Diabetes Complicat 12:81–87 Martini F, Kremling E (1999) Bilateral atraumatic avulsion fracture of the calcaneal tubercle in osteomalacia during fluoride therapy. Acta Orthop Scand 70:91–92 Squires B, Allen PE, Livingstone J et al (2001) Fractures of the tuberosity of the calcaneus. J Bone Joint Surg (Br) 83(1):55–61 Wren TA, Yerby SA, Beaupré GS et al (2001) Influence of bone mineral density, age, and strain rate on the failure mode of human Achilles tendons. Clin Biomech (Bristol, Avon) 16(6):529–34
Osteoporos Int 13.
Kraal T, Somford MP, Nijssen TF et al (2013) Conservative treatment of a calcaneal avulsion fracture partly consisting of a large bone spur. Curr Orthop Pract 24(3):355–357 14. Lee SM, Huh SW, Chung JW et al (2012) Avulsion fracture of the calcaneal tuberosity: classification and its characteristics. Clin Orthop Surg 4(2):134–8. doi:10.4055/cios.2012.4.2.134 15. Pepper M, Akuthota V, McCarty EC (2006) The pathophysiology of stress fractures. Clin Sports Med 25(1):1–16, vii. Review 16. Robb CA, Davies MB (2003) A new technique for fixation of calcaneal tuberosity avulsion fractures. Foot Ankle Surg 9(4): 221–4
17. 18. 19. 20. 21. 22.
Fitzpatrick LA (2002) Secondary causes of osteoporosis. Mayo Clin Proc 77:453–8 Orwoll ES, Klein RF (1995) Osteoporosis in men. Endocr Rev 16: 87–116 Pernow Y, Granberg B, Sääf M et al (2006) Osteoblast dysfunction in male idiopathic osteoporosis. Calcif Tissue Int 78:90–7 Al-Oanzi ZH, Tuck SP, Raj N et al (2006) Assessment of vitamin D statusin male osteoporosis. Clin Chem 52:248–54 Tuck SP, Raj N, Summers GD (2002) Is distal forearm fracture in men due to osteoporosis? Osteoporos Int 13(8):630–6 Painter SE, Kleerekoper M, Camacho PM (2006) Secondary osteoporosis: a review of the recent evidence. Endocr Pract 12:436–45
CASE REPORT
A tuber calcanei avulsion fracture developed on the basis of idiopathic osteoporosis in a young male: a case report R. Terzi 1 & T. Özer 2
Received: 29 January 2015 / Accepted: 17 March 2015 # International Osteoporosis Foundation and National Osteoporosis Foundation 2015
Abstract Calcaneus fractures constitute 1.2 % of all fractures. Tuber calcanei avulsion fractures constitute 1.3–2.7 % of calcaneus fractures. Osteoporosis, osteomalacia, and diabetes mellitus have been reported to increase the risk of development of these fractures. It has been reported that tuber calcanei avulsion fractures in elderly females might develop due to osteoporosis. As far as we know, no tuber calcanei avulsion fracture developing on the basis of osteoporosis without presence of a trauma has been reported in young males in the literature. In the current case report, a 41-yearold male patient who was admitted with complaints of pain in the left heel and diagnosed with calcaneal avulsion fracture that developed on the basis of idiopathic osteoporosis and who was treated with conservative methods was presented. Keywords Avulsion fractures . Calcaneus fractures . Idiopathic male osteoporosis . Osteoporosis
Introduction Fractures that develop as a result of the detachment of a small part of the bony structure from the main bone at the site of attachment of the ligament or tendon to the bone following a strong muscle contraction are known as avulsion fractures. Avulsion fractures generally develop following a trauma or a
* R. Terzi [email protected] 1
Department of Physical Medicine and Rehabilitation, Kocaeli Derince Education and Research Hospital, Derince, Kocaeli, Turkey
2
Department of Radiology, Kocaeli Derince Education and Research Hospital, Derince, Kocaeli, Turkey
forced activity [1]. It is frequently observed in athletes [2], dancers [3], and children [4]. It has been reported in the literature that the most common regions in which avulsion fractures develop are pelvis [2], tibia [5], metatarsals [6], and calcaneus [7]. Calcaneus fractures constitute 1.2 % of all fractures. Tuber calcanei avulsion fractures constitute 1.3–2.7 % of calcaneus fractures [8]. In the literature, osteoporosis, osteomalacia, diabetes mellitus, peripheral neuropathy, and long-term immunosuppressive therapy have been reported to increase the risk of development of these fractures [9–11]. It has been reported that tuber calcanei avulsion fractures in elderly females might develop due to osteoporosis [12, 13]. As far as we know, no tuber calcanei avulsion fracture developing on the basis of osteoporosis without presence of a trauma has been reported in young males in the literature. In the current case report, a 41-year-old male patient who was admitted with complaints of pain in the left heel and diagnosed with calcaneal avulsion fracture that developed on the basis of idiopathic osteoporosis and who was treated with conservative methods was presented.
Case A 41-year-old male patient was admitted to our clinic with complaints of pain in the left heel. He stated that he had pain for approximately 2 weeks, and pain increases with loading. The patient’s medical history revealed that he had been diagnosed in another center with soft tissue injury, and nonsteroidal anti-inflammatory drugs and cold application had been recommended. There was no previous history of trauma in the patient. He stated that he had been working in the automotive sector and approximately 1 month prior, he changed departments, and in the new department that he works, he had
Osteoporos Int
to remain standing. There was no history of chronic disease or cigarette and alcohol use. Upon physical examination, there was tenderness on compression at the site of attachment of the Achilles tendon in the left heel and minimal edema in the heel. The foot ankle joint mobility was normal, but there was pain during ankle dorsiflexion. Upon physical examination, no skeletal system deformity was observed. The left foot roentgenogram was normal, except increased ray transmission (Fig. 1). In T1- and T2-weighted images on magnetic resonance imaging, an oblique hypointense fracture line and signal change consistent with an avulsion fracture were observed at the site of attachment of the Achilles tendon to the calcaneal tubercle (Fig. 2). As the patient had a calcaneal fracture without trauma and as he had increased ray transmission on the foot roentgenogram, bone mineral density was evaluated. Dual energy X-ray absorptiometry (DEXA) revealed a lumbar 1– 4 Z-score of −3.2, T-score of -3.2, and BMD 0.728 and a femoral Z-score of −1.7, T-score of −1.9, and BMD 0.736. It was thought that the avulsion fracture might have developed on the basis of osteoporosis. On laboratory tests that were conducted to determine the etiology of osteoporosis, fasting blood glucose, urea, creatinine, ALP, total protein, calcium, phosphor, PTH, and TSH were 81 mg/dl, 21 mg/dl, 0.81 mg/dl, 80 U/L, 7.7 gr/dl, 10 mg/dl, 2.7 mg/dl, 53 pg/ml, and 1.2 ng/ml, respectively. Calcium and phosphor in the 24-h urine sample were 207 and 699 mg/day, respectively. Testosterone, cortisol, FSH, LH, and ACTH were 7.4 ng/ml, 12.1 μg, 4.6 micU/ml, 4 micU/ml, and 52 pg/ml, respectively. Anti-endomisium antibody was negative, osteocalcin was 3.4 ng/ml, Beta-CTx was 0.2 ng/ml, sedimentation rate was 2 mm/h, CRP was negative, and hemogram was normal; 25 (OH) vitamin D3 levels were 17 ng/ml. Secondary causes of osteoporosis were excluded, and the patient was diagnosed with idiopathic male osteoporosis. For vitamin D deficiency, vitamin D at a dose of 50,000 IU/week was administered for 6 weeks, calcium was administered at a dose of 800 mg/day, and analgesic treatment (paracetamol 2000 mg/day) was regulated. He
Fig. 2 T1-weighted (a) and fat suppression T2-weighted (b) MR sections of the foot that were obtained in the sagittal plane. Hypointense fracture line in oblique course in calcaneal tubercle (arrow) and a signal increase consistent with bone marrow edema in fractured bone that does not demonstrate complete separation in the T2A section (b)
was consulted by the orthopedics and traumatology department. A short foot plaster was applied, and immobilization was recommended. At the end of 6 weeks, the fracture was completely healed, and the pain regressed almost completely. Joint mobility and isometric exercises were recommended, and he was followed-up. Seventy mg/week alendronate was prescribed for osteoporosis treatment.
Discussion
Fig. 1 Direct roentgenogram of the patient. No pathology was observed in calcaneal tubercle except slight loss of density
Tuber calcanei avulsion fractures are rarely observed extraarticular injuries [8]. The diagnosis depends on clinical suspicion, detailed history, physical examination, and imaging methods. Generally, it could be confused with similar clinical conditions such as foot sprains [14]. It was learned that the patient had had a different diagnosis in his first evaluation.
Osteoporos Int
Sudden and forceful dorsiflexion of the foot in the plantar flexion position, sudden contraction of triceps surae muscle during knee extension or direct trauma to the heel are thought to be responsible for the development of tuber calcanei avulsion fractures [14]. The patient had no previous history of trauma. He had stated that his working conditions changed approximately 1 month prior. We know that stress fractures develop as a result of injuries developing due to repeated use that exceeds the bone’s individual repair capacity [15]. As the working conditions of the patient became heavier, this might have triggered fracture development based on osteoporosis. Lee et al. [14] classified tuber calcanei avulsion fractures in four categories. According to this, type 1 is simple extraarticular type, type 2 is oblique fracture defined as beak fracture, type 3 is infrabursal avulsion fracture, type 4 is defined as a beak fracture in the shape of a small triangle fragment including deep fibers of the Achilles tendon. It has been reported that type 1 fractures in particular are related to osteoporotic failure fractures and are generally observed with minor trauma and in elderly individuals [8], whereas other types of fractures are commonly observed in younger males [14]. On MR imaging of the present case, an avulsion fracture was observed, which does not demonstrate a complete separation in calcaneal tubercle at the site of the attachment of the deep fibers of the Achilles tendon. According to this, the present case was evaluated as a type 4 calcaneal avulsion fracture that developed on the basis of osteoporosis without the presence of a trauma. The young age of the patient is its interesting feature. It has been reported that the calcaneal fractures that develop on the basis of osteoporosis are more frequently observed in females in their seventh decades [11, 16]. Generally, as osteoporosis is not thought to develop in young males, it could be overlooked [16]. Especially young males in which these types of fractures are detected without the presence of a trauma should be evaluated in terms of osteoporosis. These patients should be evaluated in terms of the secondary causes of osteoporosis, such as hypogonadism, glucocorticoid excess, alcoholism, gastrointestinal diseases, hypercalciuria, cigarette smoking, chronic anticonvulsant use, immobilization, osteogenesis imperfecta, homocystinuria, neoplastic diseases, rheumatoid arthritis, hyperthyroidism, and hyperparathyroidism [17]. In the present patient, no secondary cause of osteoporosis was found and he was diagnosed with idiopathic male osteoporosis. Osteoblast dysfunction or reduction in IGF-1 levels is found to be responsible for the etiology of idiopathic male osteoporosis [18]. In the literature, no clinical or laboratory etiological factors could be detected in approximately 40 % of male osteoporosis [19]. In the laboratory findings of the patient, only 25 (OH) vitamin D levels were found to be low. In their study that has been conducted in males with idiopathic osteoporosis, Al-Oanzi ZH et al. [20] found significantly high levels of D vitamin binding protein and significantly low levels of free plasma 25(OH) Vitamin D levels.
The treatment of calcaneal avulsion fractures change according to age, functional status, and level of separation of bony fragment. It has been reported that favorable results could be obtained through treatment with functional boats or plaster at equine position in non-separated fractures or fractures which are separated less than 1 cm [21]. Surgical techniques including various internal fixation methods should be preferred in fractures that are separated more than 1 cm [16]. Loading should be limited for 8–12 weeks [22]. In the present patient, successful treatment was achieved with conservative methods. Avulsion fractures that develop on the basis of osteoporosis could be observed not only in the elderly, but also in young male individuals. These patients should be evaluated in terms of osteoporosis.
Conflict of interest None.
References 1.
2.
3.
4.
5.
6.
7.
8.
9. 10.
11. 12.
Rotman J, Loftus M, Bartolotta R (2014) Avulsion fractures in the foot: telltale radiographic signs to avoid mismanagement. Clin Imaging. doi:10.1016/j.clinimag.2014.11.015 Osbahr DC, Chalmers PN, Frank JS et al (2010) Acute, avulsion fractures of the medial epicondyle while throwing in youth baseball players: a variant of Little League elbow. Shoulder Elb Surg 19(7): 951–7. doi:10.1016/j.jse.2010.04.038 Quarrier NF, Wightman AB (1998) A ballet dancer with chronic hip pain due to a lesser trochanter bony avulsion: the challenge of a differential diagnosis. J Orthop Sports Phys Ther 28(3):168–73 Tudisco C, Giovarruscio R, Febo A et al (2010) Intercondylar eminence avulsion fracture in children: long-term follow-up of 14 cases at the end of skeletal growth. J Pediatr Orthop B 19(5):403– 8. doi:10.1097/BPB.0b013e32833a5f4d Hayashi S, Nishiyama T, Fujishiro T et al (2011) Avulsion-fracture of the anterior superior iliac spine with meralgia paresthetica: a case report. J Orthop Surg (Hong Kong) 19(3):384–5 Lambers K, Ring D (2011) Elbow fracture-dislocation with triceps avulsion: report of 2 cases. J Hand Surg [Am] 36(4):625–7. doi:10. 1016/j.jhsa.2010.12.027 Shahid MK, Punwar S, Boulind C et al (2013) Aircast walking boot and below-knee walking cast for avulsion fractures of the base of the fifth metatarsal: a comparative cohort study. Foot Ankle Int 34(1):75–9. doi:10.1177/1071100712460197 Radzilani M, D’Alton E, Golele RG (2010) Avulsion fracture of the calcaneal tuberosity: a soft tissue complication from delayed treatment. Foot Ankle Online J 3:1 Hedlund L, Maki D (1998) Calcaneal fractures in diabetic patients. J Diabetes Complicat 12:81–87 Martini F, Kremling E (1999) Bilateral atraumatic avulsion fracture of the calcaneal tubercle in osteomalacia during fluoride therapy. Acta Orthop Scand 70:91–92 Squires B, Allen PE, Livingstone J et al (2001) Fractures of the tuberosity of the calcaneus. J Bone Joint Surg (Br) 83(1):55–61 Wren TA, Yerby SA, Beaupré GS et al (2001) Influence of bone mineral density, age, and strain rate on the failure mode of human Achilles tendons. Clin Biomech (Bristol, Avon) 16(6):529–34
Osteoporos Int 13.
Kraal T, Somford MP, Nijssen TF et al (2013) Conservative treatment of a calcaneal avulsion fracture partly consisting of a large bone spur. Curr Orthop Pract 24(3):355–357 14. Lee SM, Huh SW, Chung JW et al (2012) Avulsion fracture of the calcaneal tuberosity: classification and its characteristics. Clin Orthop Surg 4(2):134–8. doi:10.4055/cios.2012.4.2.134 15. Pepper M, Akuthota V, McCarty EC (2006) The pathophysiology of stress fractures. Clin Sports Med 25(1):1–16, vii. Review 16. Robb CA, Davies MB (2003) A new technique for fixation of calcaneal tuberosity avulsion fractures. Foot Ankle Surg 9(4): 221–4
17. 18. 19. 20. 21. 22.
Fitzpatrick LA (2002) Secondary causes of osteoporosis. Mayo Clin Proc 77:453–8 Orwoll ES, Klein RF (1995) Osteoporosis in men. Endocr Rev 16: 87–116 Pernow Y, Granberg B, Sääf M et al (2006) Osteoblast dysfunction in male idiopathic osteoporosis. Calcif Tissue Int 78:90–7 Al-Oanzi ZH, Tuck SP, Raj N et al (2006) Assessment of vitamin D statusin male osteoporosis. Clin Chem 52:248–54 Tuck SP, Raj N, Summers GD (2002) Is distal forearm fracture in men due to osteoporosis? Osteoporos Int 13(8):630–6 Painter SE, Kleerekoper M, Camacho PM (2006) Secondary osteoporosis: a review of the recent evidence. Endocr Pract 12:436–45
