Editing Inclusion body myositis (section)

==Signs and symptoms==
[[File:Affected quadriceps (rectus femoris) in IBM.png|thumb|right|Affected quadriceps (rectus femoris) in IBM]]

sIBM causes progressive muscle weakness.<ref name="Weihl2019Review" /> How sIBM affects individuals is variable, including the age of onset (which generally varies from the forties upwards) and rate of progression. Because of this variability, there is no "textbook case".<ref>{{Cite journal |last1=Evangelista |first1=Teresinha |last2=Weihl |first2=Conrad C. |last3=Kimonis |first3=Virginia |last4=Lochmüller |first4=Hanns |last5=Clemen |first5=Christoph |last6=Deshaies |first6=Ray |last7=Evangelista |first7=Teresinha |last8=Eymard |first8=Bruno |last9=Greensmith |first9=Linda |last10=Hilton-Jones |first10=David |last11=Kimonis |first11=Virginia |last12=Kley |first12=Rudy |last13=Lochmüller |first13=Hanns |last14=Meyer |first14=Hemmo |last15=Mozaffar |first15=Tahseen |date=August 2016 |title=215th ENMC International Workshop VCP-related multi-system proteinopathy (IBMPFD) 13–15 November 2015, Heemskerk, The Netherlands |journal=Neuromuscular Disorders |language=en |volume=26 |issue=8 |pages=535–547 |doi=10.1016/j.nmd.2016.05.017 |pmid=27312024 |pmc=5967615 |issn=0960-8966}}</ref>

Common early symptoms include frequent tripping and falling and difficulty going up stairs. [[Foot drop]] in one or both feet can occur.<ref>{{Cite web|title=Inclusion Body Myositis|url=https://understandingmyositis.org/myositis/inclusion-body-myositis/|access-date=2021-06-12|website=www.google.com}}</ref> Part of the cause for this dysfunction is the early involvement of the [[quadriceps]] muscles.<ref name="Weihl2019Review" /> Weakness of the [[tibialis anterior muscle]] is responsible for foot drop. Another common early symptom is trouble manipulating the fingers, such as difficulty with tasks such as turning doorknobs or gripping keys. Weakness of finger flexion and ankle dorsiflexion occurs early.<ref name="Weihl2019Review" /> sIBM also preferentially affects the [[List of flexors of the human body#Upper limb|wrist flexors]], [[biceps]], and [[triceps]].<ref name="Weihl2019Review" />

During the course of the illness, the patient's mobility is progressively restricted as it becomes difficult to bend down, reach for things, and walk quickly. Many patients say they have balance problems and fall easily, as the muscles cannot compensate for an off-balanced posture. Because sIBM makes the leg muscles weak and unstable, patients are very vulnerable to serious injury from tripping or falling down. Although pain has not been traditionally part of the "textbook" description, many patients report severe muscle pain, especially in the thighs.{{citation needed|date=February 2021}}

[[File:Inclusion body myositis arms.png|thumb|left|Affected arms and fingers in IBM]]

Progressive difficulty swallowing ([[dysphagia]]) is present in 40 to 85% of IBM cases and often leads to death from [[aspiration pneumonia]].<ref name="pmid18936555">{{cite journal |vauthors=Oh TH, Brumfield KA, Hoskin TL, Kasperbauer JL, Basford JR |title=Dysphagia in inclusion body myositis: clinical features, management, and clinical outcome |journal=Am J Phys Med Rehabil |volume=87 |issue=11 |pages=883–9 |year=2008 |pmid=18936555 |doi=10.1097/PHM.0b013e31818a50e2 |s2cid=11878442 }}</ref>

IBM can also result in diminished capacity for aerobic exercise. This decline is most likely a consequence of the sedentary lifestyle leading to disuse [[muscle atrophy]] that is often associated with the symptoms of IBM (i.e. progressive muscle weakness, decreased mobility, and increased level of fatigue). Therefore, one focus of treatment should be the improvement of aerobic capacity.<ref>{{cite journal  |vauthors=Johnson LG, Collier KE, Edwards DJ, et al |title=Improvement in aerobic capacity after an exercise program in sporadic inclusion body myositis |journal=J Clin Neuromuscul Dis |volume=10 |issue=4 |pages=178–84 |date=June 2009 |pmid=19494728 |doi=10.1097/CND.0b013e3181a23c86 |s2cid=14686189 }}</ref>

Patients with sIBM usually eventually need to resort to a cane or a walker and in most cases, a wheelchair eventually becomes a necessity.

"The progressive course of s-IBM leads slowly to severe disability. Finger functions can become very impaired, such as manipulating pens, keys, buttons, and zippers, pulling handles, and firmly grasping handshakes. Arising from a chair becomes difficult. Walking becomes more precarious. Sudden falls, sometimes resulting in major injury to the skull or other bones, can occur, even from walking on minimally irregular ground or from other minor imbalances outside or in the home, due to weakness of quadriceps and gluteus muscles depriving the patient of automatic posture maintenance. A foot-drop can increase the likelihood of tripping. [[Dysphagia]] can occur, usually caused by upper esophageal constriction that often can be symptomatically improved, for several months to years, by bougie dilation per a GI or ENT physician. Respiratory muscle weakness can sometimes eventuate."<ref name="pmid16432144">{{cite journal |vauthors=Askanas V, Engel WK |title=Inclusion-body myositis: a myodegenerative conformational disorder associated with Abeta, protein misfolding, and proteasome inhibition |journal=Neurology |volume=66 |issue=2 Suppl 1 | pages = S39–S48 |year=2006 |pmid=16432144 |doi=10.1212/01.wnl.0000192128.13875.1e|s2cid=24365234 }}</ref>