Paget's/OP Flashcards
What is the typical clinical presentation of Paget’s?
- Often no symptoms
- May be incidental finding on imaging or inc ALP
- If you have symptoms the most common is pain (persistent, sleeping)
- Can also have OA, nerve impingement
- Deformities = bowing of lower limbs
- Fractures = complete (transverse) or fissure, long bone
- Warm skin over area
- Steal syndrome = hypervascularity of bone so adjacent gets ischemic, intermittent claudication
- Neurologic = HA, spinal stenosis, hearing loss
- Neoplastic transformation = osteosarcoma, giant cell tumours
Indications for tx of Paget’s
- Symptomatic disease
- Asymptomatic - location risk for future complications, and signs of active disease with inc ALP or bone scintigraphy)
- Surgery planned at active site
- Hypercalcemia in setting of immobilization
Treatment for Paget’s
Zoledronic acid - 5 mg, single 15 min IV infusion
Risedronate - 30 mg/day x 2 months (less effective)
Alendronate 40 mg/day x 6 months
Calcitonin if intolerant of bisphosphonates
Denosumab - may be good in renally impaired, not great data
What marker should be followed during tx for Paget’s?
ALP
Measure no earlier than 3 mos after start tx, ideal 6 mos
Check ALP q3 mos for first 6 mos the annually
Complications of Paget’s
Neurologic: nerve root compression, CN entrapment, deafness, spinal stenosis, vascular steal syndrome
Orthopaedic: secondary OA, pathologic #, bone deformity, inc bleeding in surgery
Oncologic: osteosarcoma, giant cell tumors
Metabolic: secondary hyperPTH, hyperCa, hypercalciuria
Goals of treatment in Paget’s
Serum ALP normal
Resolution of symptoms
Radiographic improvement
What is the cause of Paget’s?
Familial and sporadic forms
Viral cause
How is Paget’s diagnosed?
Radiologic - characteristic deformity of bone, thickened cortices, tunnelling and accentuated trabeculae
Baseline radionuclide bone scan in all patients (extent, location)
XR other areas if found
What are the main classes of treatment options for osteoporosis?
- Bisphosphonate (alendronate, risedronate, ZA)
- RANKL inhibitor (denosumab)
- PTH analogue (Teriparatide)
- SERM (raloxifene)
- Anti-sclerostin antibodies (romosozumab)
Bisphosphonate mechanism and side effect
Mechanism: taken up by osteoclasts during bone resorption inhibiting OC resorptive ability and triggering apoptosis
SFx: upper GI, MSK discomfort, ZA - flu like, hypoCa
Rare: ONJ, AFF
Denosumab mechanism and side effect
Mechanism: monoclonal Ab that binds to RANKL, prevents it from binding to RANK which prevents OC maturation
SFx: MSK discomfort, hypoCa, dermatitis/infection
Rare: oNJ, AFF
Teriparatide mechanism and side effect
Mechanism: PTH analogue that activates PTH R = inc activity of OB and OC = overall net bone gain
SFx: MSK discomfort, hyperCa, hypercalciuria, nausea, orthostatic HOTN
Raloxifene mechanism and side effect
Mechanism: SERM, binds to estrogen R, provides mixed antagonist-agonist effect, weak anti resorptive effects to reduce risk of vertebral #
SFx: thromboembolic, CVD, stroke, vasomotor, leg cramps
Romosozumab mechanism and side effect
Mechanism: anti sclerotin antibody, sclerotin inhibits OBs, Ab stimulates formation and inhibits resorption due to effects on osteoprotegerin levels
SFx: MI, stroke, hypoCa, muscle discomfort
Rare: ONJ, AFF
5 ways romosozumab increases bone mineralization
Inc OB differentiation from mesenchymal stem cells
Reduces OB apoptosis
Inc bone matrix formation
Downregulates RANKL production (dec OC formation and bone resorption)
Upregulates OPG production (binds and opposes RANKL)
Increases BMD of L spine and total hip
5 management strategies for dx of vertebral fracture
- Pain control: oral (acetaminophen, ibuprofen, naproxen), opioid if 1-2 wks of inadequate analgesia (IR, lowest dose)
- Activity/early mobility - ASAP, complete bed rest not recommended
- PT - gait and core strengthening
- Bone density - OP defining fracture, baseline BMD, start OP therapy
- Vertebral augmentation - vertebroplasty or kyphoplasty (only if debilitating pain or substantial functional limits after min 3 weeks therapy)
Clinical Frailty Scale
1 - Very fit (robust, regularly exercise)
2 - Fit (no active disease sx, active seasonally)
3 - Managing well (med probs well controlled, not regularly active beyond walking)
4 - Very mild frailty (symptoms limit activity)
5 - Mild frailty (need help with higher IADLs)
6 - Mod frailty (help all outside activities, keeping house, maybe bathing/dressing)
7 - Severe frailty (completely dependent for personal care)
8 - Very severe frailty (completely dependent, approaching end of life)
9 - Terminally ill (life expectancy <6 mos, not otherwise living with severe frailty)
Risk of discontinuing denosumab
Sudden discontinuation comes with risk of vertebral fractures due to rapid increase in bone turnover (OC activity) and subsequent bone loss
Most bone loss in 12 mos
Switch to alternative antiresorptive and closely monitor for min 12 mos
Imaging findings of atypical femoral fracture
Location: femoral diaphysis
Cortical (endosteal/periosteal) thickening
Must involve lateral cortex
Mainly transverse (medially may be oblique)
No or minimal comminution
Management of AFF
- Stop bisphosphonate
- Consult ortho - surgery with intramedullary nail if complete #, disabling pain, or incomplete not improved by 2-3 mos
- Ensure adequate vit D and Ca
- Consider teriparatide (don’t change to denosumab if on bisphosphonate)
- Image contralateral femur