Anti-epileptic drugs are commonly prescribed drugs for seizure disorders as well as other medical conditions including psychiatric disorders, migraine headaches, chronic pain, and neuropathy. A common side effect anti-epileptic medications includes loss of bone density and increased fracture risk. Of all the anti-epileptic medications, Dilantin (phenytoin) is the most widely prescribed and causes the most bone loss. Phenytoin decreases bone density twice as fast as other anti-epileptic medications including phenobarbital, carbamazepine, and carbetrol. Anti-epileptic medications decease bioavailable vitamin d which decreases calcium absorption. The resulting hypocalcemia increases parathyroid (PTH) secretion causing hyperpararthyroidism. An increase in PTH pulls more calcium from bones. Hyperparathyroidism causes poor bone mineralization and an increased risk of non-traumatic fractures. Patients on these medications should have more frequent vitamin d monitoring and should take twice the recommended daily dose or 2,000 to 4,000 IU/day. Patients found to be osteoporotic on DXA or at high risk of fracture should be treated according to the National Osteoporosis Foundation treatment guidelines. 1,2
Answer D.
References
1. Panday K, Gona A, Humphrey MB. Medication-induced osteoporosis: screening and treatment strategies. Ther Adv Musculoskelet Dis. 2014 Oct; 6(5): 185–202.
2. Pack AM. The Association Between Antiepileptic Drugs and Bone Disease. Epilepsy Curr. 2003 May; 3(3): 91–95.

The patient presents with a minimally displaced greater tuberosity fracture. The patient’s x-rays were read as normal in the emergency room and she was unaware she had a fracture. The greater tuberosity is an attachment site for the supraspinatus and infraspinatus tendons. The greater tuberosity can fracture with a direct blow to the shoulder (an impaction injury) or from a fall on an outstretched hand causing an avulsion injury. A greater tuberosity fracture can also occur in up to 30% of shoulder dislocations. 1,2
A non-displaced fracture may be subtle on x-ray and is often missed. Non-displaced and minimally displaced fractures can be treated in a sling immobilizer to avoid active abduction for 4-6 weeks. Displacement of fractures greater than 5 mm should be fixed with open reduction and internal fixation. Displaced fractures can result in impingement on the under surface of the acromion and a poor functional outcome. Displaced fractures retract posteriorly and superiorly causing impingement in abduction and external rotation. Standard x-rays including grashey AP, outlet view, and axillary view are usually adequate to determine the amount of displacement and indicated treatment. MRI may be utilized for suspected occult fractures not visible on x-ray. 1,2

References.
1. Wilcox RB, Arslanian LE, Millett PJ. Management of a patient with an isolated greater tuberosity fracture and rotator cuff tear. JOSPT 2005 35. 521-530.
2. Parsons BO, Klepps SJ, Miller S, Bird J, Gladstone J, Flatow E. Reliability and Reproducibility of Radiographs of Greater Tuberosity Displacement: A Cadaveric Study. JBJS 2005. 87-A (1). 58-65.

Most humeral shaft fractures heal well with non-operative treatment. Initial management in the emergency room often includes a coaptation splint or U-shaped splint that goes into the axilla on the medial side and past the deltoid on the lateral side of the arm. The splint is removed during the first follow-up office visit, generally at 4-5 days after the injury. The patient is then converted to a functional brace that provides circumferential compression around the fracture site. Galveston and Sarmiento humeral braces are examples of functional braces as they allow for immediate range of motion of the elbow and wrist. Keeping the arm in adduction is advised as the weight of the arm with gravity helps reduce the shaft fracture. Abduction and forward flexion of the arm creates displacing forces and should be avoided until he fracture heals. Criteria for acceptable alignment in the brace includes less than 20 degrees of anterior angulation, less than 30 degrees of varus/valgus angulation, and less than 3 cm of shortening. 1,2
Radial nerve palsy, a potential complication of humeral shaft fractures, can occur in up to 11% of patients and is more common in comminuted or oblique fracture patterns. Radial nerve palsy spontaneously resolves in 70% of patients in an average of 7 weeks. Absolute indications for surgery include open fracture or neurovascular injury. Relative indications for open reduction and internal fixation include bilateral humerus fractures or polytrauma, pathological fractures, irreducible fractures, and nonunions. Open reduction and internal fixation has a lower risk of complications compared to intrameduallary nails and is the generally preferred surgical option. 1,2

References
1. Sarmiento, Augusto; Waddell, James P.; Latta, Loren L. Diaphyseal Humeral Fractures: Treatment Options. Journal of Bone & Joint Surgery – American Volume . 83(10):1566-1579, October 2001.2.
2. Carroll EA, Schweppe M, Langfitt M, Miller AN, Halvorson JJ. Management of Humeral Shaft Fractures. JAAOS 2012; 20: 423-433.

The patient has a grade 1 degenerative spondylolisthesis. Spondylolisthesis is a forward slippage of one vertebral body over another. Spondylolisthesis is graded by the amount or degree that a vertebral body has slipped forward over the body beneath it. Grade 1 includes (0-25%) forward slip over the inferior body, grade 2 (25-50%), grade 3 (50-75%), grade 4 (> 75%), and grade 5 (> 100%). Slip beyond grades 1-2 are rare. There are 6 types of spondylolisthesis including dysplastic, isthmic, degenerative, traumatic, pathological, and postsurgical. Dysplastic or congenital abnormalities may be due to hypoplastic facets or poorly developed pars and symptoms most commonly occur at 4-6 years of age. Isthmic spondylolisthesis is due to spondylolysis or fracture of the pars and is one of the most common causes of lower back pain in children and adolescents. Degenerative type is caused by a degenerative cascade that includes facet joint degeneration, intervertebral disc degeneration, and ligamentous laxity. Degenerative type commonly presents in women over the age of 40 at the L4-L5 level.  The less common traumatic, pathological, and postsurgical types are caused by an acute fracture other than the pars, weakened bone from diseases (osteoporosis, tumor, etc), and slippage after surgery from excessive resection of supporting structures, respectively. 1,2

The most common symptom of degenerative spondylolisthesis includes mechanical back pain that is relieved with rest or sitting. Neurogenic claudication or buttock and leg pain while walking is also a common complaint. Flexion and extension films help determine stability of the slip; instability is defined as 4 mm of translation or 10 degrees of angulation of motion compared to the adjacent motion segment.  Conservative treatment includes oral NSAIDS, physical therapy for core strengthening, and epidural steroid injections for radicular pain. Lumbar decompression and instrumented fusion may be indicated if patients fail at least 6 months of conservative treatment, have progressive motor deficits, or cauda equina syndrome. Less than 30% of patients presenting with grades 1 and 2 will have slip progression. 1

References

1. Spondylolisthesis. http://www.orthobullets.com. Accessed on 11/16/16.
2. Degenerative Spondylolisthesis. http://www.wheelesonline.com Accessed on 11/16/16.

The differential diagnosis for this finding includes osteomyelitis and a bone tumor.  Lymphoma and multiple myeloma are unlikely because these are usually diaphyseal.  Ewing sarcoma usually has periosteal reaction, which is not evident on this film.  There is no calcification within the lesion, which us usually seen in a chondrosarcoma.  Furthermore, this lesion is not as well defined as would be expected for a giant cell tumor or a eosinophilic granuloma.

The patient had an MRI which further demonstrated the lesion and the patient was referred to an orthopedic oncologist for evaluation.  The patient was diagnosed with osteosarcoma and had an amputation.  He was treated with chemotherapy prior to the amputation and for the year following.  He is now 15 years old and is cancer free.

Osteosarcoma is the sixth most common malignancy in childhood.  The peak occurrence is usually during the adolescent growth spurt and suggests a relationship between rapid bone growth and malignant transformation.  This type of bone tumor occurs most frequently at sites where the greatest increase in length and size of bone occurs.  The metaphyses of long tubular bones are primarily affected, with the distal femur accounting for more than 40% of cases.  The most common presenting symptom is pain over the involved area with or without soft tissue mass.  Usually the patient has had the pain for several months prior to diagnosis and systemic symptoms are rare.  The patient may have an elevated serum alkaline phosphatase or LDH levels.  X ray findings show destruction of the normal bony trabecular pattern with indistinct margins.  There is also periosteal new bone formation.  A soft tissue mass is frequently noted as well.  MRI is more sensitive in defining the extent of the primary tumor.  The most common sites of metastases are the lung and additional boney sites.  A tissue sample is needed for confirmation of the diagnosis.  The surgeon who will be carrying out any additional surgical procedures should perform the biopsy because the placement of the incision for biopsy is important.  Historically, patients receiving surgery alone developed pulmonary metastases within 6 months of surgery, however, with adjuvant chemotherapy, disease free survival rates increased in patients followed for 3-10 years.  Survival rates were shown to improve when chemotherapy was initiated prior to the surgery and continued for one year following.  Relapses beyond 3 years are unusual.  Patients with localized disease with 90% tumor necrosis have a 70-85% long-term, disease-free survival rate.

References

Graham DK, Craddock JA, Quinones RR, Keating AK, Maloney K, Foreman NK, Giller RH, Greffe BS. Neoplastic Disease. In: Hay WW, Jr., Levin MJ, Deterding RR, Abzug MJ. eds. CURRENT Diagnosis & Treatment: Pediatrics, 22e. New York, NY: McGraw-Hill; 2013. http://accessmedicine.mhmedical.com/content.aspx?bookid=1016&Sectionid=61604063. Accessed April 22, 2015.

Miner Haygood T, Sayyouh MH. Chapter 6. Musculoskeletal Imaging. In: Chen MM, Pope TL, Ott DJ. eds. Basic Radiology, 2e. New York, NY: McGraw-Hill; 2011. http://accessmedicine.mhmedical.com/content.aspx?bookid=360&Sectionid=39669014. Accessed April 22, 2015.