Musculoskeletal Flashcards
Muscles of the rotator cuff
Supraspinatus Infraspinatus Teres Minor Subscapularis (SITS)
Supraspinatus origin, insertion, innervation and function
- Supraspinous fossa
- superior facet of greater tuberosity
- Suprascapular nerve (C5)
- abduction
Infraspinatus origin, insertion, innervation and function
- infraspinous fossa
- middle facet of greater tuberosity
- suprascapular nerve (C5-6)
- External rotation
Teres minor origin, insertion, innervation and function
- lateral border of scapula
- inferior facet of greater tuberosity
- axillary nerve (C5)
- external rotation
Subscapularis origin, insertion, innervation and function
- subscapular fossa
- lesser tuberosity of humeral neck
- upper and lower subscapular nerves (C5-6)
- internal rotation
Red flag conditions of the shoulder and when to consider them
Polymyalgia rheumatica - bilateral shoulder pain and weakness
Acute compartment syndrome - pain disproportionate to injury, may result from significant limb swelling following injury or excessively tight bandage or cast
Open fractures
Fractures with nerve or vascular compromise
Skin or joint infections
Neoplasia
Serious and life-threatening conditions mimicking shoulder pain - e.g. referred ischaemic pain
What is impingement syndrome of the shoudler
The subacromial bursa and supraspinatus tendon become compressed between the humeral head, the acromion and the coraco-acromial ligament -> pain with forward elevation of the arm and narrowing of the subacromial space
Causes of impingement syndrome of the shoulder
Functional
- poor control of shoulder stabilisers (cephalad slippage of humeral head compressing the subacromial space, may result from overuse of shoulder, injury to shoulder resulting in altered biomechanics and poor stabiliser control)
Anatomical
- arthritis
- hypertrophic changes of the acromion -> narrowed subacromial space
Clinical presentation of impingement syndrome of the shoulder
Pain, especially with overhead movements of the arm
Sometimes lying on the affected shoulder at night may cause pain
Clinical examination findings in impingement syndrome of the shoulder
Positive Hawkins test (most sensitive, poorly specific)
Painful arc test - pain from 60-120 degrees improving at approx 120
Empty can test (highly specific for supraspinatus tear)
What is Hawkins test, what does it demonstrate and how is it performed?
Highly sensitive, poorly specific test for subacromial impingement.
With patient standing, elevate humerus to 90 degrees, 30 degrees anteriorly (ensuring humerus in line with scapula), flex elbow 90 degrees
Internally rotate the glenohumeral joint
Pain = positive test
What is painful arc test, how is it performed and what does it demonstrate
Patient actively abducts both arms together.
Test is positive for subacromial impingement if patient experiences pain between 60-120 degrees of abduction, then improving.
Pain presenting only at 170-180 degrees more likely to be secondary to acromial pathology
What is Jobe’s test, how is it performed and what does it demonstrate
AKA Empty Can test, highly specific for supraspinatus tear, but poorly sensitive
Elevate arms to 90 degrees angle forward 30 degrees
Internally rotate shoulder by pointing thumb down to ground
Apply downward force as patient attempts to resist
Pain worse on internal rotation v external rotation = positive
Management of subacromial impingement
Address underlying cause
Physio indicated most of the time
Surgical management unlikely to be of benefit, especially if functional cause (acromioplasty has no additional benefit over structured and supervised exercise program)
Cause of anterior shoulder instability
Secondary to acute or chronic stretching of the anterior shoulder capsule - can occur following anterior shoulder dislocation and subluxation
more commonly caused by repetitive and progressive stress on anterior shoulder capsule from loading and stretching beyond functional range (Swimmers, baseball pitchers)
Also frequently seen in resistance trainers using incorrect technique or too heavy weights (particularly in supine or semi-recumbent position)
Clinical presentation of anterior shoulder instability
Nonspecific symptoms are common
Shoulder ache
Occasional clicking or clunking
Pain may wake the patient at night when lying on the affected shoulder
If longstanding (or pronounced) laxity, may have hand or arm nerve symptoms from proximal nerve traction
Examination findings in anterior shoulder instability
Often unremarkable
Anterior and posterior drawer test to check for laxity of glenohumeral joint
Sulcus test:
- applying downward traction to humerus produces sulcus under acromion if positive
Anterior release test: (relatively highly sensitive and specific)
- patient supine, abduct and externally rotate shoulder
- examiner’s hand closest to patient applies downward force over humeral head attempting to relocate and secure it in the glenoid
- while firm pressure applied, externally rotate arm further (humeral head suddenly released)
- patient may experience pain, apprehension or combination
Management of anterior shoulder instability
Imaging if traumatic shoulder dislocation has occurred (pre- and post- reduction)
- all first time dislocations refer to PT and ortho assessment due to high risk of re-dislocation
No data to guide management of instability from chronic over use ?identify and correct predisposing factors +/- refer to PT
If instability does not improve, ortho opinion may be indicated
Rotator cuff tears
Common
Increase with age
>50% patients >50y have a tear (symptomatic or asymptomatic)
May be partial or full thickness - pain and dysfunction does not appear to correlate with degree of tear
Often progress from tendinopathy to tear if not addressed early
May occur as result of direct trauma or progressive wear and tear
Clinical presentation of rotator cuff tear
Broad spectrum of presentation
May present with symptoms similar to anterior shoulder instability
May have pain or weakness attempting to elevate arm
May be pain at night lying on affected shoulder
If longstanding may have numbness and tingling in affected arm
May have normal or near-normal shoulder function due to recruiting other muscles to perform task of injured muscle
Examination of rotator cuff tear
Useful in helping to diagnose ACUTE tears only, less useful in chronic tear
- Jobe’s test/empty can test (highly specific for supraspinatus tear, poorly sensitive)
- Drop arm test: abduct arm to 90 degrees and have patient slowly descend with control - if unable to do so = positive (highly specific, poorly sensitive)
Management of rotator cuff tears
Early referral to physio!!
If acute, in younger age group and affecting comfort and/or function, imaging may be beneficial
If secondary to sudden trauma, occurring in younger age group and impacting comfort and/or function, ortho opinion may be indicated
Imaging and surgical management are otherwise of little benefit
Presentation of acromioclavicular joint pain
If acute: patient will remember mechanism of injury (typically a fall or impact onto the shoulder tip)
Often painful area poorly localised -> diffuse shoulder pain
Sleeping on affected side disturbs sleeo
Across body movements with affected arm may cause pain
If Osteoarthritic joint, may not recall injury. Increasing pain over time of a diffuse nature. may occur under repetitive stress to joint e.g. bodybuilders, weightlifters.
Examination findings in acromioclavicular joint problems
Point tenderness over AC joint
O’Brien test AKA Active compression test
- highly specific for AC joint pain
- stand behind patient or to affected side
- flex arm to 90 degrees with elbow extended, adducted 15 deg medially
- internally rotate so thumb pointing to floor, then resist downward force
- supinate so palm facing upward, resist downward force
- positive and diagnostic of AC joint pathology if pain in thumb down position reduced in palm up position
Management of acromioclavicular joint pathology
Refer to physiotherapist
Simple acute sprains often settle with conservative management
Supportive shoulder strapping
- needs to be tight as may stretch by up to 40%
- hypoallergenic tape under strapping tape allows it to be left in place for 4-5 days, dry it if gets wet
If not responding to appropriate conservative management, may benefit from intraarticular corticosteroid injection
History needed for knee injury work up
history of the injury is the most useful in narrowing down diagnosis
Weight bearing at time of injury?
Stress on joint? (valgus, varus, rotational)
Impact
Sound and feeling (pop, shift)
Post injury details (collapse, inability to weight bear or continue play)
Knee swelling and how rapidly ?haemarthrosis
Clicking, locking and instability
Indications for ortho referral post knee injury
Urgent:
- fracture
- lipohaemarthrosis
- neurovascular compromise
Prompt:
- locking
- intra-articular loose bodies
- painful or very large effusion
- meniscal tears
- instability
- persisting antalgic gait
- ACL rupture
Mechanism of injury for collateral ligament injuries
Valgus (MCL) or varus (LCL) force occurring through flexed knee
Symptoms of collateral ligament injury
Pain +/- instability in medial or lateral knee (respective of CL injured), particularly with change of direction movements
Examination findings in collateral ligament injury
With knee in 30 degrees flexion (and repeat in full extension), apply a varus or valgus stress through the knee
- Grade I: pain without laxity (<3mm laxity)
- Grade II: often more painful with 5-10mm laxity
- Grade III: may be less painful as ligament has ruptured, >10mm laxity
Management of collateral ligament injuries
RICE for firs 48 hours
MCL: all grades indicate conservative management
- hinged knee brace to compensate for instability
- 6-12 week physio guided rehabilitation
LCL injuries are rare and often associated with ACL and/or PCL rupture so should be referred for ortho review
Meniscal injuries epidemiology
Medial meniscus restricted by attachment to deep fibres of MCL, therefore more commonly injured than more mobile lateral meniscus
In younger patients with meniscal injuries, commonly an associated ligamentous injury
Mechanism of meniscal injury
Compression with rotational forces through the knee
Symptoms of meniscal injury
“twinge” or sudden pain over medial or lateral joint line, with clicking, catching or locking
May be able to continue play with some discomfort
Subacute onset of effusion
Examination findings of meniscal injuries
Medial or lateral joint line tenderness (highly sensitive, poorly specific) McMurray test (poorly sensitive, highly specific) - Patient supine on bed, hold knee and palpate joint line with one hand, other hand holds sole of foot, starting in maximal flexion, extend knee with INTERNAL rotation and VARUS stress, then return to maximal flexion and repeat with EXTERNAL rotation and VALGUS stress - positive if pain, snapping, audible clicking or locking
IR + varus = lateral
ER + valgus = medial
Diagnosis of meniscal injury
Best confirmed with MRI (GP rebatable)
Management of meniscal injury
RICE for 48h
Some small tears may become asymptomatic and trial of conservative management in small, minimally symptomatic tears over 4 weeks is appropriate
All others need ortho review +/- meniscal debridement +/- repair
History of patella dislocation
Sensation of something “popping” out in the knee
Severe pain
Episode of instability
Tense haemarthrosis
Examination findings in patella dislocation
Tenderness of medial patella facet and medial retinaculum
Positive patella apprehension test
- Part 1: knee in full extension, apply lateral force to patella with thumb, move knee to 90 deg flexion and back to full extension maintaining force on patella
- Part 2: repeat as above but with MEDIAL force applied to patella with index finger
Positive if - apprehension (oral or quadriceps recruitment) on part 1 with alleviation on part 2
Management of traumatic patella dislocation
RICE for 48h Refer for arthroscopy if: - traumatic loose body - large fracture on xray - painful haemarthrosis
all patients require physio program focusing on vastus medialis strengthening to prevent recurrence
Healing capacity of ACL
poor due to poor blood supply (in contrast to PCL)
Mechanism of injury in ACL rupture
Athlete lands with heel strike though weight bearing limb (often with valgus or rotational force)
Symptoms of ACL rupture
Sensation of pop or shift in knee
Immediate severe pain, easing within minutes, after which may be able to weight bear gingerly
Rapid development of swelling
Examination findings in ACL rupture
first need to exclude PCL injury
- Lachman test demonstrates laxity: (patient supine on bed, place knee 20-30deg flexion, slight external rotation, place one hand behind tibia and other on patients thigh. Pull tibia anteriorly, if anterior translation or tibia with soft/mushy “end feel” then positive, >10mm or >2mm more than unaffected knee suggests torn ACL)
- Pivot-shift test to confirm diagnosis
(patient supine, hold leg with hip flexed and 30 degrees abducted in slight internal rotation, anterior pressure on fibula in attempt to subluxdibia forward, then move knee into flexion - positive if tibia is reduced back at 30-40deg flexion (often clunk sound and give way feeling to patient))
Investigation of ?ACL injury
Plain x-ray - may show fracture of tibial plateau or avulsion of tibial spines
MRI:
- may be performed prior to ortho appointment to expedite treatment - can also provide details about associated injuries
Management of ACL injury
RICE 48h
Surgical reconstruction for patients wanting to maintain active lifestyle (often 6 weeks after injury once swelling resolves)
PT guided rehab
- ideally commence prior to surgery
- unable to compete in competitive sports for 9-12 months post injury
Mechanism of injury in PCL rupture
Fall onto knee with impact to anterior tibia
Symptoms of PCL rupture
Instability descending stairs and walking downhill
May have surprisingly little other functional losas
Examination findings in PCL rupture
Posterior sag with knee flexed to 90deg (high sensitivity and specificity)
Positive posterior drawer test
- patient supine on bed with knee flexed to 90 deg
- examiner sit on toes to stabilise
- grasp proximal lower leg at tibial plateau or joint line
- attempt to translate lower leg posteriorly - positive if lack of end feel or excessive posterior translation
Diagnosis of PCL injury
MRI will confirm and exclude associated injury
Management of PCL injury
Isolated ruptures can almost always be managed conservatively
- RICE for 48h
- severe injuries may require immobilisation in long hinged knee brace for analgesia
Physio guided rehab
Refer to sports physician to exclude occult injuries and detect any early complications of conservative management
(PCL sprains can be managed by GP without referral)
Ottawa knee rules
Knee x-ray indications after acute knee injury:
- Age >55y
- Tenderness at head of fibula
- Isolated tenderness of the patella
- Inability to flex knee to 90 degrees
Inability to bear weight (take 2 steps on each leg) immediately and at presentation
