PURPOSE: The accessory bones around the elbow are very rare variant structures, present in approximately 0.7% of cases. They can cause diagnostic problems and can be mistaken for pathological structures, especially when pain and limitation of elbow movements are present and a trauma can be traced in the patient's history. They are of different nature, either presenting within muscle tendons as sesamoids (brachialis and triceps brachii muscles) or presenting intra-articularly probably as separated or accessory ossification centres. The least common is the os supratrochleare anterius. METHODS: We present a case of a young male, featuring chronic blocking and 20° limited flexion of his right elbow, which bothered him during his occupation as a locksmith. In history, he suffered minor trauma to the elbow 20 years ago. X-ray and CT showed a large ossicle in the coronoid fossa of the humerus. RESULTS: The ossicle was surgically extracted in small pieces. The patient left satisfied with no mention of complaints. CONCLUSION: The os supratrochleare anterius is a very rare accessory bone of the elbow, located in the coronoid fossa of the humerus which can mimic many pathological states, and limit movements and causing pain around the elbow.

• Keywords
• Accessory bone, Accessory ossicle, Elbow, Os supratrochleare anterius,
• MeSH
• Anatomic Variation * MeSH
• Humerus diagnostic imaging   MeSH
• Humans MeSH
• Elbow Joint * MeSH
• Tomography, X-Ray Computed MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH
• Review MeSH

Several accessory bones can be found around the wrist, which may pose a diagnostic challenge. Hereby, we report a unique case of a traumatic fracture of an aberrant os styloideum in a 66-year-old male. The patient presented with a swollen dominant right hand and a hematoma on its anterior and posterior aspects, as a result of a fall on an outstretched hand. The diagnosis was based on a CT scan, which showed a fractured accessory bone between the distal portion of the capitate bone and the base of the third metacarpus. Due to its typical location, the ossicle was identified as os styloideum. The patient was treated conservatively and the symptoms subsided on a short forearm cast after 2 weeks. At a 12-month follow-up, no other episodes were declared. Strong anatomical knowledge and sharing of such cases is essential for proper diagnosis and treatment of this very rare condition.

• Keywords
• Accessory bone, Carpal bone, Fracture, Os styloideum, Variation, Wrist,
• MeSH
• Fractures, Bone * MeSH
• Carpal Bones * MeSH
• Humans MeSH
• Tomography, X-Ray Computed MeSH
• Aged MeSH
• Accidental Falls MeSH
• Wrist Joint MeSH
• Check Tag
• Humans MeSH
• Male MeSH
• Aged MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH

PURPOSE: Cubital tunnel syndrome is a well-described entity with many reported etiologies and anatomical compression sites. Accessory ossicles of either traumatic or congenital origin might occur around the elbow joint. Only one case reporting such ossicles compressing the ulnar nerve exists in previous literature. We aim to present this entity with a detailed description of the patient history and treatment. CASE REPORT: We report a case of 30-year-old female presenting with classical signs of cubital tunnel syndrome-positive Wartenberg's and Froment's signs, hypoesthesia in the fourth and fifth finger with decreased finger duction strength but without gross hypotrophy of interosseous and hypothenar muscles. Tinel's sign was positive over the ulnar sulcus and an accessory ossicle was found on the elbow radiograph within the ulnar sulcus. The first signs of calcification in this patient were reported 6 years prior in a follow-up after the dislocation of her elbow joint following a bike accident. The EMG confirmed ulnar nerve neuropathy in the elbow area. The ossicle was extirpated, the ulnar nerve was decompressed in the ulnar sulcus in a standard manner and the symptoms quickly resolved. The patient has been regularly visiting our outpatient clinic for the next 12 years without any complaints considering her elbow and the ulnar nerve. CONCLUSION: This is a rare case of cubital tunnel syndrome caused by an accessory ossicle of traumatic origin. Simple bone extirpation with ulnar nerve release followed by anterior subcutaneous transposition is the recommended method of treatment. No report of congenital accessory bones causing ulnar nerve compression in the elbow exists in the literature.

• Keywords
• Accessory bones, Cubital tunnel syndrome, Pathologic ossification, Ulnar nerve neuropathy,
• MeSH
• Adult MeSH
• Ossification, Heterotopic * diagnosis   diagnostic imaging   MeSH
• Humans MeSH
• Elbow MeSH
• Elbow Joint * physiology   MeSH
• Ulnar Nerve MeSH
• Cubital Tunnel Syndrome * MeSH
• Check Tag
• Adult MeSH
• Humans MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Case Reports MeSH

INTRODUCTION: Anatomical variants observed during the posterior approach to the elbow joint require special attention due to their clinical relevance. We aim to present a compendious review of described variants potentially encountered during the posterior approach towards the elbow joint to the experts in the elbow surgery. METHODS: A narrative review of surgical and anatomical textbooks, as well as search of scientific databases was carried out. RESULTS: Variability of the subcutaneous nerves is important during incision planning. Accessory muscles such as dorsoepitrochlearis, chondroepitrochlearis, epitrochleoanconeus, subanconeus or supernumerary flexor carpi ulnaris may confuse even the senior surgeon during the dissection and possibly complicate the fracture reduction. Some bony variants such as supratrochlear foramen may lead to fracture or possibly interfere with the osteosynthesis placement. Accessory bones are also present in the region of the elbow joint. Those situated intra-articular may present with symptoms. CONCLUSION: Many variants can be encountered in the area of the elbow joint and their knowledge is essential to truly understand its anatomy. The presented review enables easier orientation in the current literature with the aim on the posterior approach towards the elbow joint.

• Keywords
• Accessory bones, Chondroepitrochlearis, Dorsoepitrochlearis, Epitrochleoanconeus, Posterior approach, Subanconeus, Ulnar nerve, Variability around elbow joint,
• MeSH
• Muscle, Skeletal surgery   MeSH
• Humans MeSH
• Elbow innervation   MeSH
• Elbow Joint * anatomy & histology   MeSH
• Elbow Injuries * MeSH
• Forearm surgery   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH