title: Spontaneous rupture of the long head of the biceps tendon in a woman with hypothyroidism: a case report.
abstract: BACKGROUND
  Tendinitis can be a presenting complaint in hypothyroidism, with symptomatic relief being obtained by appropriate management of the primary thyroid deficiency. To the best of our knowledge no other cases of spontaneous rupture of the long head of the biceps tendon during uncontrolled hypothyroidism have yet been reported.
  
  
  METHODS
  This case report describes an unusual case of spontaneous rupture of the long head of the biceps tendon in a 48-year-old white woman with severe hypothyroidism. She described experiencing a sudden sharp pain and an audible pop in her right shoulder while using her personal computer. On physical examination she was positive for Yergason's sign and a subsequent magnetic resonance imaging scan showed complete rupture of the long head of her biceps tendon. Laboratory tests revealed significantly elevated thyrotropin levels (>100 μIU/ml) and very low levels of both triiodothyronine (0.17 ng/ml) and free thyroxine (0.18 ng/dl). She was switched to a different thyroxin regimen with a progressive dosage increment. She declined surgical re-anchorage of the tendon but despite the discreet Popeye sign, her overall strength and shoulder function were satisfactory. After 2 months, she was found to be clinically euthyroid, having normal thyroid function tests (thyrotropin 2.95 μIU/mL, free thyroxine 1.07 ng/dl). At her last follow-up visit, 1 year post-injury, she reported nearly normal shoulder function in her daily activities and had a constant shoulder score of 93 points.
  
  
  CONCLUSIONS
  The role of thyroid hormones in the synthesis and degeneration of collagen and in the proliferation and apoptosis of human tenocytes is discussed, providing a possible mechanism whereby hypothyroidism may lead to tendon tears. This report may have a greater impact among different subspecialties as it presupposes a high degree of awareness from internists, endocrinologists and orthopedic surgeons.
authors.affiliation: Department of Shoulder and Elbow Surgery, University of Patras, 26500, Patras, Greece. pantazis.kon@gmail.com.
authors.forename: K
authors.initials: K
authors.lastname: Pantazis
authors.affiliation: Division of Endocrinology, Diabetes and Metabolic Diseases, Department of Internal Medicine, University of Patras, 26500, Patras, Greece. nikosroupas@hotmail.com.
authors.forename: N D
authors.initials: ND
authors.lastname: Roupas
authors.affiliation: Department of Shoulder and Elbow Surgery, University of Patras, 26500, Patras, Greece. andpan21@gmail.com.
authors.forename: Andreas
authors.initials: A
authors.lastname: Panagopoulos
authors.affiliation: Department of Internal Medicine, University of Patras, 26500, Patras, Greece. roula-theodor@hotmail.com.
authors.forename: S
authors.initials: S
authors.lastname: Theodoraki
authors.affiliation: Department of Internal Medicine, University of Patras, 26500, Patras, Greece. agtsintoni@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: Tsintoni
authors.affiliation: Division of Endocrinology, Diabetes and Metabolic Diseases, Department of Internal Medicine, University of Patras, 26500, Patras, Greece. vkyriazopoulou@med.upatras.gr.
authors.forename: V
authors.initials: V
authors.lastname: Kyriazopoulou
mesh_terms: D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000150:complications* / Q000503:physiopathology*; D007103:Immobilization; D008875:Middle Aged; D016059:Range of Motion, Articular; D017006:Rotator Cuff / Q000503:physiopathology; D012422:Rupture, Spontaneous / Q000150:complications / Q000209:etiology; D012785:Shoulder Joint / Q000503:physiopathology*; D020069:Shoulder Pain / Q000188:drug therapy / Q000209:etiology*; D013710:Tendons / Q000503:physiopathology*; D013960:Thyroid Function Tests / Q000379:methods; D013972:Thyrotropin / Q000097:blood*; D013974:Thyroxine / Q000627:therapeutic use*; D016896:Treatment Outcome
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D013972:Thyrotropin; D013974:Thyroxine