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46 Cards in this Set
- Front
- Back
A 26-year-old rugby player has been having progressive anterior pelvic pain for the last 3 months. He is diagnosed with osteitis pubis, and a non-operative treatment regimen is initiated. Which of the following figures represents this patients diagnosis?
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bony erosion and irregularity with early widening of the pubic symphysis.
B2.11 (DSC-traffic light)-xray, MRI, bone scan B2.12 AP pelvis:osteolytic pubis with bony erosions and often times diastasis of the symphysis -degenerative changes within the joint can be seen B2.14 MRI bone marrow edema found early; bone scan-increased activity in area of pubic symphysis tx-NSAIDS, rest, activity modification |
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osteitis pubis
A1 what is it ? A-5 epid-doing A-6 MoI A-7 symptoms (traffic light) A8-DDX/MISC (star) |
A1-Inflammation of the pubic symphysis caused by repetitive trauma
A-5common in soccer, hockey, football and running A-6 repetitive microtrauma repetitive kicking sports involving hip repetitive adduction/abduction A-7 --vague, ill-defined muscular pain with activities; -involving hip adduction/abduction anterior pelvis -spasms with hip adduction A-8-Athletic publagia,-Stress fracture of the pubic rami -Stress fracture of the femoral neck;-Inguinal hernia; -Oncologic disease (rare) |
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A-2 def/Dx,
A 66-year-old male presents with a three-month history of increasing right shoulder pain. He denies any trauma or prior shoulder problems, and has good rotator cuff strength. His medical history is significant for Crohn's disease which is controlled medically with prednisone therapy during flares. A current MRI image of his shoulder is shown in Figure A. What is the most likely diagnosis? Tx according stage? |
4. Osteonecrosis
The atraumatic lesion shown in Figure A is most consistent with osteonecrosis (also known as avascular necrosis, or AVN). Initial MRI findings of AVN include decreased signal intensity in the subchondral region on both T1- and T2-weighted images, suggesting edema in early disease. In the shoulder, this is most commonly associated with the chronic use of corticosteroids, such as prednisone. tx- (Cruess Stage I & II)->core decompression (Cruess Stage III and IV)->hemiarthroplasty (Cruess V)-.total shoulder arthroplasty |
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Avascular Necrosis of the Shoulder
A-2 def/Dx, A-3 cause (gold) |
A-2A caused by interruption of blood supply to humeral head
A-3 (remember ASEPTIC pneumonic) 1 Alcohol; 2AIDS 3 Steroids (most common), 4 Sickle, 5 SLE 6 Erlenmeyer flask (Gaucher’s) 7 Pancreatitis 8 Traumatic, -4-part fx/dislc (app. 100% AVN);9-4-part displaced (45% AVN);10-4-part-valgus impacted (11% AVN);11 -3-part(14% AVN) 12Idiopathic;13 Infection 14 Caisson’s (the bends) (diver) |
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Cruess Classification (start-stages) & Tx
A-4 pathoanatomy A-5 epid-doing A-7 symptoms A8-DDX/MISC |
Type I Normal x-ray. Changes on MRI, Tx-core decompression
Type II Sclerosis (wedged, mottled), osteopenia; Tx-core decompression Type III Crescent sign indicating a subchondral;Tx-hemiarthroplasty Type IV Flattening and collapse;Tx-hemiarthroplasty Type V Degenerative changes extend to glenoid tX-TSA A-4Pathoanatomy-decreased blood supply to humeral head leading to death of cells in bony matrix causing subchondral bone collapse and may lead to joint incongruity and arthritic changes A-5 Diver A-7 insidious onset of shoulder pain, often without a clear inciting event, pain, loss of motion, crepitus, and weakness 1-Gaucher disease large boney infarcts on MRI and severe pain. It is also a less common cause of AVN than chronic corticosteroid use. 2-Osteoarthritis is not frequently associated with subchondral collapse and fragmentation, especially in the absence of prior symptoms. |
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B2.10 What do you see?
B2.12 (RXrV &PPFs?) Recommended X-ray SEEING? B2.13 PathoPnemonic Findings |
(RXrV &PPFs?)5 views-(Grashey view)/AP 0 rotation AP-IR, AP-ER, Axillary view, scapular Y)
no findings on radiograph at onset of disease process osteolytic lesion develops on radiograph demonstrating resorption of subchondral necrosis most common initial site is superior middle portion of humeral head B2-13 crescent sign demonstrates subchondral collapse may progress to depression of articular surface and consequent arthritic changes. |
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B2.11 diagnostic study of choice? (DSC)
B2.14 RmriP/PS & MRI-fs?)MRI Plane/Pulse sequence- SEE'g: |
B2.11MRI preferred imaging modality
~100% sensitivity in detection will demonstrate edema at the site of subchondral sclerosis |
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C1.1 what is the treatment?
C1.2 conservative treatment? C1.3 surgical indications C1.4 SI-image findings |
C1Nonoperative
pain medications, activity modification, physical therapy indications first line of treatment technique C1.2 physical therapy- restrict overhead activity and manual labor c1.4 indications early disease (Cruess Stage I and II)-core decompression C1.4 indications moderate disease (Cruess Stage III and IV)-hemiarthroplasty C1.5 indications advance stage (Cruess V)- total shoulder arthroplasty |
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A-4
A 37-year-old severe asthmatic has been taking daily corticosteroids for twenty years and now reports 4 months of worsening left shoulder pain. He is unable to complete a full day of work due to the pain. A radiograph is provided in Figure A. Which of the following describes the pathogenesis behind this disease process? FIGURES: A |
4. Cellular death of the subchondral bone following an interruption in the vascular supply
Answers 1, 2, 3, and 5 describe rheumatoid arthritis, Reiter's Syndrome, gout, and septic arthritis respectively. Cell-mediated immune response inciting synovial hypertrophy and mononuclear destruction of cartilage 2. Humoral immune response following a systemic infection in an HLA-B27 positive individual 3. Hyperuricemia induced crystalline deposition within the synovial fluid 5. Bacterial seeding of the joint inducing polymorphonuclear cell destruction of the cartilage |
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A1/C1
A 34-year-old competitive weightlifter presents with increasing pain during bench pressing. His physical exam demonstrates slight weakness in external rotation. Radiographs are unremarkable. His MRI findings are seen in Figure A. Treatment should include which of the following? |
Spinoglenoid cyst decompression with posterior labral repair
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A 44-year-old male presents with a 2 month history of posterior shoulder pain. He is noted to have normal forward flexion and abduction strength and isolated weakness on shoulder external rotation. He has slight atrophy of his periscapular area. He has no numbness or paraesthesias. Which pathology would best explain his symptoms?
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Entrapment of the suprascapular nerve at the spinoglenoid notch would cause isolated infraspinatus muscle weakness and atrophy in the infraspinatus fossa.
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A 29-year-old male volleyball player presents with a one year history of right shoulder weakness and deep aching pain. He denies any history of trauma or prior shoulder problems. A clinical photograph and representative MRI image are shown in Figures A and B respectively. He is diagnosed with a ganglion cyst of the shoulder. Based on the images provided, where is the cyst located?
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Entrapment of the suprascapular nerve at the spinoglenoid notch would cause isolated infraspinatus muscle weakness and atrophy in the infraspinatus fossa.
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A patient with shoulder pain and weakness has an MRI showing a cyst in the suprascapular notch. Which of the following muscles is most likely to show weakness?
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The suprascapular notch is proximal to the point where the suprascapular nerve innervates both the supraspinatus and the infraspinatus, therefore compression would cause weakness of both.
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A 21-year-old collegiate volleyball player is noted to have weakness in external rotation and isolated atrophy of the infraspinatus on physical examination as seen in Figure A. An axial MRI image is shown in Figure B. This clinical condition is most likely caused by compression of the
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The clinical presentation is consistent for a suprascapular neuropathy caused by compression of the suprascapular nerve by a cyst in the spinoglenoid notch. The suprascapular nerve arises from the upper trunk of the brachial plexus with contributions from C5-6. It travels through the suprascapular notch of the scapula where it gives motor branches to the supraspinatus then around the spinoglenoid notch where it innervates the infraspinatus.
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A patient is scheduled to undergo arthroscopy for a SLAP tear of his shoulder. Based on the MRI shown in Figure A, what additional physical exam finding is the patient likely to display?
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Figure A shows a cyst in the spinoglenoid notch, where it may impinge on the suprascapular nerve as it travels around the glenoid and under the spine of the scapula on its way to innervate the infraspinatus muscle. Prolonged impingement on the suprascapular nerve by a spinoglenoid cyst can result in atrophy of the infraspinatus muscles. This would show up as weakness in external rotation on exam. These cysts are associated with SLAP lesions and per literature are formed by a one-way valve effect, where synovial fluid can exit the joint into the cyst but not drain spontaneously
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A 25-year-old volleyball player has recurrent right shoulder pain. On exam she has right shoulder weakness to external rotation with her arm at her side and atrophy below the scapular spine. There is no external rotation lag sign. Jobe drop arm and Hornblowers tests are negative. The O'Brien's test is positive. What will most likely be found on MRI of her shoulder?
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This is a classic case of suprascapular nerve impingment at the spinoglenoid notch, likely from a cyst associated with a posterior SLAP tear. Compression of the suprascapular nerve at the spinoglenoid notch causes isolated infraspinatus weakness while compression at the suprascapular notch would affect both the supraspinatus and infraspinatus. A posterior SLAP tear is suspected with a positive O'Brien's active compression test.
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Suprascapular Neuropathy
A1 what is it ?/A-3 cause, A-4 Associations |
A-1Suprascapular notch entrapment
weakness of both supraspinatus and infraspinatus spinoglenoid notch entrapment weakness of infraspinatus only |
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A-4 pathoanatomy (traffic light)
A-7 symptoms |
travels across posterior triangle of neck to scapula
A-4 proximal compression of suprascapular nerve in the suprascapular notch leads to weakness of both supraspinatus and infraspinatus-compression can be from ganglion cyst (often associated with labral tears) transverse scapular ligament entrapment fracture callus symptoms deep, diffuse, posterolateral shoulder pain |
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B1.1 How do you know?- Suprascapular notch entrapment
B1-2 PE-Inspection/Palpation, B1-3 provocative test B1-7 motor strength/nerve innervation B1-4 origin/Insertion B1-8 pulses B1-9 reflexB1-6(nvck) dermatone sensation B2.10 What do you see? B2.11 diagnostic study of choice? (DSC) B2.12 (RXrV &PPFs?) Recommended X-ray SEEING? B2.13 PathoPnemonic Findings B2.14 RmriP/PS & MRI-fs?)MRI Plane/Pulse sequence- SEE'g: B2.15 location (mus-tendon juction/interstetial/bony avulsion) B2.16 degree of sTrain (complete vs partial vs microscopic), B3.17 any confirmation test? |
B1.1 leads to weakness of both supraspinatus and infraspinatus
B1.2 physical exam- deep, diffuse, posterolateral shoulder pain, pain with palpation of suprascapular notch, atrophy along the posterior scapula B1.3/B1-7 (Jobe test positive) Synonyms: "Empty can"test weakness of supraspinatus, weakness seen with shoulder abduction to 90 degree, 30 degrees forward flexion, and with internal rotation & weakness of infraspinatus, weakness to external rotation with elbow at side May have positive evaluation findings for SLAP Tear, unstable type II and IV superior labral lesions. -Obrien's Test (Active Compression test) (+)when there is pain in the glenohumeral joint while the forearm is pronated but not when the forearm is supinated -Crank Test(+) positive when there is clicking or pain in the glenohumeral joint |
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C4:
C5 -scapular pain with vague sensory changes. -supraspinatus, infraspinatus, deltoid -DDX:Upper cord brachial plexus palsy, suprascapular N palsy, axillary N palsy C6 -Retroscapular, thumb, index finger pain -Biceps, brachioradialis, pronator teres -DDX: brachial plexus palsy, C7 -retroscapular pain, pain/numbness in long & middle fingers -triceps, wrist, finger extensors and flexors -brachial plexus palsy, radial nerve palsy, median nerve palsy C8 - medial forearm, ring & small finger numbness/pain -finger extensors & flexors, intrinsics -lower cord brachial plexus palsy, radial / median / ulnar nerve palsy T1-same as C8 above T2 |
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Supraclavicular nerve
Axillary nerve (superior lateral brachial cutaneous n.) Intercostobrachial nerve and medial brachial cutaneous nerve Medial antebrachial cutaneous nerve Lateral antebrachial cutaneous nerve Ulnar nerve Median nerve Inferior lateral brachial cutaneous branch of Radial nerve. Posterior brachial cutaneous branch of Radial nerve. Inferior lateral brachial cutaneous branch of Radial nerve. Posterior antebrachial cutaneous branch of Radial nerve. Superficial and digital branchs of Radial nerve. Superficial branch of Radial nerve. |
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Origin
Insertion Action Arterial Supply |
Origin Supraspinous fossa of scapula
Insertion Superior facet on greater tuberosity of humerus Action Initiates and assists deltoid in abduction of arm and acts with other rotator cuff muscles Innervation Suprascapular nerve (C4, C5 and C6) (C4, C5, C6) Arterial Supply Suprascapular artery |
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Origin
Insertion Action Innervation Arterial Supply |
Origin Infraspinous fossa of scapula
Insertion Middle facet on greater tuberosity of humeruss Action Laterally rotate arm; helps to hold humeral head in glenoid cavity of scapula Innervation Suprascapular nerve (C5 and C6) (C5, C6) Arterial Supply Suprascapular and circumflex scapular arteries |
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Which of the following should be avoided in early rehabilitation following posterior cruciate ligament (PCL) reconstruction?
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Prone hamstring curls
Resisted hamstring strengthening exercises (ex. hamstring curls) are generally avoided in the early phase of rehabilitation following PCL reconstruction - this is because the hamstrings create a posterior pull on the tibia which increases stress on the graft. Kaufman et al studied the joint reactive forces during isokinetic exercises. They found that posterior shear forces exist during the flexion portion of isokinetic exercise and during extension exercises at knee joint angles greater than 40 degrees. The maximum posterior shear force was 1.7 body weight. |
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A 23-year-old collegiate soccer player sustained a right knee injury 6 months ago. He has been treated with rest and rehabilitation but is unable to play at his previous level due to his knee "giving way." Physical exam reveals 10° varus alignment when standing and a varus thrust with walking. Strength is full compared to the other side. Ligamentous exam reveals a stable ACL and MCL, but opens to a varus stress and a 3+ posterior drawer and positive dial test at both 30° and 90° degrees of flexion. What is the best treatment option to allow this patient to return to competitive athletic activity?
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High tibial osteotomy to increase tibial slope and correct varus malalignment; reconstruction of the PCL & PLC.
The 3+ posterior drawer indicates the PCL injury while the opening to varus stress indicates injury to the lateral collateral ligament (a component of the PLC). In addition, this patient has a positive dial test at both 30° (PLC tear) and 90° (PLC and PCL tear) degrees of flexion |
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Which of the following rehabilitation principles is true regarding non-operative treatment of a grade II PCL tear
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Quadriceps strengthening and prone range of motion should begin as tolerated
Range of motion is typically initiated early. Flexion may be done in a prone position to limit posterior sag. While quadriceps strengthening is essential, resisted hamstring exercises are generally avoided initially because they pull the tibia in a relatively posterior position. |
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At what angle of knee flexion should the graft be tensioned at during posterior cruciate ligament (PCL) reconstruction with a single bundle graft?
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For single bundle reconstructions, the PCL is usually tensioned in flexion and the ACL is tensioned in more extension.
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Strengthening of what muscle group most effectively counteracts the deficit seen with an incompetent PCL?
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The primary function of the PCL complex is to restrict posterior tibial translation. After acute PCL rupture or PCL reconstruction, resisted hamstring strengthening is avoided as it pulls the tibia posteriorly. Therefore, therapy should focus on quadriceps strengthening which pulls the tibia anteriorly.
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A football player sustains an isolated posterior cruciate ligament (PCL) tear. Which of the following mechanisms is most likely to have caused this injury?
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Overall the most common mechanism of PCL injury is a direct blow to the proximal aspect of the tibia. The most common mechanism of PCL injury in athletes is a fall onto the flexed knee with the foot in plantarflexion, which places a posterior forces on the tibia and leads to rupture of the PCL.
Janousek found similar results showing that MVA was more likely to result in multi-ligament injuries, while a fall on the knee with the foot plantarflexed is most likely to result in an isolated PCL injury in athletic activities. Traffic accidents (45%) and athletic injuries (40%) were the most common causes. The most common injury mechanisms were dashboard injuries (35%) and falls on the flexed knee with the foot in plantarflexion (24%). |
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A 35-year-old construction worker presents with medial-sided knee pain. He has no instability complaints but at age 18, he sustained a complete PCL injury that was treated non-operatively. A radiograph is shown in Figure A. What surgical treatment is the best option given his age and occupation?
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Medial opening wedge osteotomy of the proximal tibia
The radiographs show a knee with significant medial compartment narrowing. A frequently tested fact is that wear associated with chronic PCL instability occurs most commonly in the patellofemoral joint and the medial compartment of the knee. but the opening wedge tends to increase posterior tibial slope which is helpful in PCL-deficient knees. cruciate ligaments are required for the insertion of a unicompartmental knee replacement. Isolated PCL reconstruction would not be recommended as he already has arthritis and cruciate reconstruction in a mal-algined knee is at increased risk of failure. |
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A 35-year-old male sustained an isolated PCL injury over 5 years ago which was treated non-operatively. If his follow-up radiographs show degenerative changes related to his PCL-deficiency, the changes are likely to be present in which of the following knee compartments?
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A PCL deficient knee has an increased risk of early onset of degenerative changes in the medial and patellofemoral compartments.
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Indications Total Shoulder Arthroplasty (horse)
Contraindications Total Shoulder Arthroplasty (beer) |
-pain, especially at night, and inability to perform activities of daily living
-functioning rotator cuff and adequate glenoid bone stock -symmetric posterior glenoid wear -posterior humeral head subluxation Contraindications insufficient glenoid stock rotator cuff arthropathy deltoid dysfunction -> #1 irreparable rotator cuff (hemiarthroplasty or reverse total shoulder are preferable) q infection brachial plexus palsy |
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Preoperative Imaging-Total Shoulder Arthroplasty
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-true AP
determine extent of DJD and look for superior migration of humerus -axillary view look for posterior wear of glenoid -obtain CT scan to determine glenoid version and glenoid bone stock - MRI evaluate rotator cuff condition |
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Which of the following statements regarding propionibacterium acnes infections after shoulder arthroplasty is incorrect?
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Surgeons need to be aware that P. acnes is a skin bacteria that is responsible for shoulder infections that often have a subtle presentation. Many of the traditional signs of infection such as fever, erythema and severe pain are often not present.
In fact, none of their patients presented with fevers. Initial 3 day cultures were often negative and the mean time to a positive culture was 9 days. |
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During a total shoulder arthoplasty (TSA), which of the following technical maneuvers would most likely place the rotator cuff tendons at risk of injury?
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Excessive bone removal with the humeral neck osteotomy
The rotator cuff tendons can be inadvertantly cut or detached during a TSA if the head cut is made either too distally or in excessive retroversion. A head cut in 30 degrees of retroversion is normal Excessive inclination may take too much medial bone, but if appropriately placed, would not risk injuring the rotator cuff insertion. |
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A 65 year-old man has progressive debilitating pain and crepitus in his shoulder. Active forward elevation is 120 degrees and external rotation strength is good. Radiograph and CT scan are shown in Figures A and B. Which treatment will likely give him the best outcome in 3 years.
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The patient has advanced glenohumeral arthritis with a functioning rotator cuff and adequate glenoid bone stock for immediate glenoid component implantation.
A total shoulder replacement will give the patient the best chance at better outcomes as observed in the cited studies by Gartsman and Bryant when compared to hemiarthroplasty alone for glenohumeral arthritis. A reverse total shoulder would be an appropriate option for a patient with cuff tear arthropathy. Hemiarthroplasties have been shown to have inferior outcomes to TSA’s for glenoihumeral arthritis due to painful articulation of the humeral component on arthritic glenoid. Capsular release would aid a frozen shoulder. |
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A 62-year-old man undergoes a total shoulder arthroplasty for osteoarthritis. He accidently uses his operative arm to rise from a chair 3 weeks after surgery and thereafter complains of anterior shoulder pain. Radiographs are significant for anterior dislocation of the prosthesis. What is the most likely mechanism for this complication?
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The primary restriction after total shoulder arthroplasty (TSA) is passive external rotation, as well as active internal rotation, to protect the subscapularis repair.
This patient fired his subscapularis rising from the chair. |
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The placement of a standard all-polyethylene glenoid component for shoulder arthroplasty is contraindicated in which of the following scenarios?
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If a patient has an irreparable rotator cuff tear, they will have abnormal mechanics and often develop degenerative changes referred to as rotator cuff arthropathy. The abnormal mechanics will persist even after standard total shoulder arthoplasty components are placed, with the head levering on the superior glenoid (the "rocking horse” phenomenon) which may loosen the glenoid component.
In this situation, a hemiarthroplasty or a reverse total shoulder arthroplasty would be preferrable |
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During the initial rehabilitation phase following total shoulder arthroplasty through a delto-pectoral approach, motion and strengthening are typically restricted because of which factor?
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Protect the subscapularis tendon
Through a delto-pectoral approach, the subscapularis is taken down off the humerus. passive external rotation past 30degs and active internal rotation past the plane of the body are usually restricted for several weeks to allow healing. |
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Which of the following factors has the greatest influence on early postopertive restrictions following total shoulder arthroplasty through a deltopectoral approach?
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Strength of the subscapularis repair
excessive early passive external rotation and active internal rotation past the plane of the body are rarely permitted during the first 6 weeks. |
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A 75-year-old right-hand dominant female has persistent right shoulder pain for the past 5 years. An axial CT scan is shown in the Figure A. If a total shoulder arthroplasty is planned, what other procedure must be performed based on this patient's imaging?
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The patient is being considered for total shoulder arthroplasty, but the axial CT scan demonstrates significant glenoid retroversion and loss of glenoid bone stock. This patient is at risk for glenoid component failure because of significant bone loss. Not resurfacing the glenoid and performing a hemiarthroplasty is an option.
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A 72-year-old male who underwent right total shoulder arthroplasty 8 months ago is unable to lift his right hand off his back and has weakness with internal rotation. What is the most likely diagnosis?
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Subscapularis insufficiency
Clinical findings include: -internal rotation weakness, -increased passive external rotation, -weakness to belly press, and an -abnormal subscapularis lift-off test |
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Physical exam-Rotator Cuff Arthropathy
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inspection & palpation
supraspinatus/infraspinatus atrophy prominence of humeral head anteriorly (anterosuperior escape) with elevation of arm subcutaneous effusion from loss of fluid from capsule range of motion crepitus in glenohumeral and/or subacromial joints with ROM pseudoparalysis inability to abduct shoulder provocative tests external rotation lag sign inability to maintain passively externally rotated shoulder with elbow at 90 degrees consistent with a massive infraspinatus tear Hornblower sign inabilty to externally rotate a shoulder placed in 90 degrees of flexion at elbow and 90 degrees of abduction consistent with teres minor dysfunction |
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risk factors-Rotator Cuff Arthropathy
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rheumatoid arthritis
cuff tear arthropathy crystalline-induced arthropathy idiopathic shoulder osteoarthritis hemorrhagic shoulder (hemophiliacs and elderly on anticoagulants) |
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Rotator Cuff Arthropathy-
Radiographs recommended views findings MRI |
complete shoulder series (AP, axillary, Grashey (true AP)
findings acromial acetabularization (true AP) femoralization of humeral head (true AP) asymmetric superior glenoid wear lack of osteophytes osteopenia "snowcap sign" due to subchondral sclerosis anterosuperior escape MRI shows an irreparable rotator cuff tear with masive fatty infiltration and severe retraction not necessary if humeral head is already showing anterosuperior escape on x-rays |
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Surgical indications PCL?
postoperative rehabilitation after PCL recon? Surgical indications chronic PCL deficiency |
1 PCL repair or reconstruction, isolated grade II or III with bony avulsion (ORIF for bony avulsion)
2 combined ligament injury (PCL injury with with ACL or PLC injury) - immobilize in extension early and protect against gravity -early motion should be in prone position follow with quadriceps rehabilitation -a high tibial osteotomy in a PCL deficient knee, increasing the tibial slope helps reduce the posterior sag of the tibia |
