1. Apply Evidence Based Medicine to Arthrocentesis Skills: Shoulder and Knee
Gregory C. Gardner, MD, FACP
Gilliland-Henderson Professor of Medicine
University of Washington, Seattle, WA

2. Evidence Based References
Courtney and Doherty. Best Practice & Research Clinical Rheumatology 2009; 23:161–192 (2013 update)
Crawshaw DP et al. Exercise therapy after corticosteroid injection for moderate to severe shoulder pain. BMJ 2010;340:c3037 doi: /bmj.c3037
Raynauld JP, et al. Safety and efficacy of long-term intraarticular steroid injections for osteoarthritis of the knee. Arthritis Rheum 2003;48:
Habib GS, et al. Local effectes of intra-articular corticosteroids. Clin Rheumatol 2010;29:
Gardner GC. Teaching arthrocentesis and injection techniques: what is the best way to get our point across. J Rheumatol 2007 vol. 34 (7) pp

3. Outline of Workshop Didactics Surface anatomy
Procedure pearls
Anatomy review
Clinical Issues and technique review
Surface anatomy
Present evidence based best practices

4. Current status of how we do and teach arthrocentesis and injection therapy

5. Dangers of “Evidence based Medicine”

6. Analytic rubric Procedure distilled into discrete steps:
1. Patient counseling
Discuss reasons for doing the procedure
Discuss details of doing the procedure
Discuss potential side effects
Inquire about potential contra-indications
2. Patient preparation
Able to verbalize anatomy and mark appropriate location
Patient positioned properly for site of procedure
Skin cleansed properly
Appropriate application of anesthesia

7. Analytic rubric continued
3. Needle insertion
Choose appropriate needle and syringe for procedure
Needle inserted at appropriate angle/depth
Needle/syringe stabilized during procedure
Aseptic technique
4. Post-procedure wrap-up
Skin re-cleansed if necessary, site bandaged
Post-procedure counseling provided
Sharps disposed of properly
Operator showed concern for patient comfort

8. Utility of Rubric Framework for teaching arthrocentesis skills
Can be used to think about and applying evidenced-based principles
Useful as assessment tool for physicians in training
Useful as a documentation of procedure competency

9. Procedure Pearls

10. Textbook complications of arthrocentesis & injection therapy; How much should we worry?
Charcot arthropathy – very rare; why would it develop and how often can we safely inject an joint?
Periarticular calcifications – 4% give or take may develop
Infection – very rare (TBD)
Post-injection synovitis – uncommon; 6-12 hrs following procedure and resolves in 48 hrs
Tendon rupture – rare; avoid injecting tendon especially high tension tendons i.e. Achilles
Skin depigmentation – 5%; may develop 8 wks after injection and resolve by 16 wks
Subcutaneous fat atrophy – up to 8%; avoid placing corticosteroid in subcutaneous fat
Other – AVN, hyperglycemia, flushing

11. Textbook contraindications to injecting corticosteroids into joints and soft tissue
Infection or suspected infection around the joint
Avoid injecting through psoriatic plaque
Hypersensitivity to injectables
Most “hypersensitivity” is to epinephrine; no need to use
Upcoming surgery on the joint
TBD
Suspected intra-articular fracture/joint instability
Anticoagulation
Caution not contraindication; TBD

12. Joint procedures and infection
Seror et al Rheumatology 1999
Retrospective study involving 69 French rheumatologists
Mean number of years in practice 20.9
Mean number of corticosteroid injections per year 809
Total injections 1,160,000 in 20 years with 15 instances of post injection infection
Overall rate of infection was 1/77,300
When pre-packaged CS syringes used: 1/162,000
When multi-dose vial used: 1/21,000 (7.7 X higher!)
1/4.6 rheumatologists had post-injection septic complication over 20 years
Two points:
Infection is rare with arthrocentesis and injection therapy
Issue of multidose vial especially where used by people not as thoughtful as you about sterile technique
Hollander series of 16 infections per 150,000 procedures = 1/9300

13. How often can we inject a knee?
68 knee OA pts randomized to either saline or 40 mg of triamcinolone acetate injections every 3 months for 2 years
Double blind study
After 2 years of therapy, no difference in joint space width between groups (figure)
Joint pain at night and stiffness significantly better for steroid group using AUC analysis at 2 years
Conclusion:
JS not affected
Clinical improvement especially
at 1 year, less apparent at 2 yrs
No significant SE
Raynauld et al. Arthritis Rheum 2003;48:370

14. Steroid injection into hip prior to THA Chitre et al. JBJS 2007
99 pts had received steroid/local anesthetic into hip joint 4 to 50 mo prior to THA; mean 18 mo
Follow-up 25.8 mo post-surgery with range 9-78 mo
NO instances of post-operative joint infection or sepsis occurred
Similar data from Sankar et al and Sreekumar et al in the hip and Desai et al in the knee
Data from McIntosh et al raise concern about infection if given within 6 weeks of surgery (trend but NS)
McIntosh et al. Clin Orthop Relat Res 2006

15. Best way of cleansing the skin?
Current evidence based guidelines for inserting IV catheters suggests the following is best practice according to EPIC 2, a mega- systematic review of best practices for prevention of catheter associated infections
Decontaminate the skin site with a single patient use application of alcoholic chlorhexidine gluconate solution (preferably 2% chlorhexidine gluconate in 70% isopropyl alcohol) prior to the insertion of a central venous access device. (Class A)
Use a single patient use application of alcoholic povidone-iodine solution for patients with a history of chlorhexidine sensitivity. Allow the antiseptic to dry before inserting the catheter (Class D)
Granted indwelling catheters but….
Like Chlorhexidine alcohol preps easy to use, no yellow-brown stuff to remove stain clothing; does erase any pen marks you put on the skin so need pressure mark of landmark
Journal of Hospital Infection (2007) 65S, S1–S64

16. Arthrocentesis and anticoagulation? Ahmed and Gertner Am J Med 2012
Retrospective review of complication in 640 arthrocentesis in 514 anticoagulated patients
Compared the incidence of significant bleeding in patients by INR (>2 or < 2)
Conclusion: no need to reduce anticoagulation level prior to procedures
Complication
INR >2
N=456
INR < 2
N=184
Early Bleeding
1 (0.2%)
Late Bleeding
Infection
Pain
3 (0.7%)
Comparisons between groups NS
Patient with bleeding also had pain

17. Should I use anesthesia prior to a procedure?
Park et al Rheumatol International 2009
99 patients underwent 2 arthrocenteses
One without and one with anesthesia
Procedures performed with:
Conventional syringe or
Reciprocating procedure device
Pain measured on 10 cm VAS (0 no pain; 10 unbearable pain)
Conventional syringe
Reciprocating syringe P
# of subjects 49 50
Pain w/o anesthesia
9.22
9.39 NS
Pain of anesthesia
6.18
3.96
.006
Pain after anesthesia
4.10
1.84
.003
% Pt wanting anesthesia
100% NA
Besides pain literature also indicated that anesthesia reduces procedure anxiety
Do not understand by the RPD would produce less local anesthesia pain?

18. Benefit of buffering lidocaine
Lidocaine maintained at acidic pH to increase shelf life; pH 6.2 preventing photodegradation/aldehyde formation; lidocaine-epinephrine has even lower pH (5.98)
Sodium bicarbonate neutralizes pH (7.2) but does not affect onset of action; increases efficacy via increasing uncharged form of drug
Buffering: 1 part (1mEq/ml) sodium bicarbonate to 10 parts lidocaine
Consistent literature favoring buffering:
Vasectomy
Bone marrow Bx
IV cannula insertion
Laceration repair
Etc..
We only get the 50 ml single use vial of NAHCO3
Cristoph et al. Ann Emerg Med 1988;17:

19. Cristoph et al. Ann Emerg Med 1988;17:117-120
Pain scores on VAS following intradermal infiltration of unbuffered and buffered local anesthesia
Pain on VAS
6.21
7.22
5.98
7.16
6.18
7.20
pH noted
Cristoph et al. Ann Emerg Med 1988;17:

20. 18 gauge in articular cartilage
Needles: Primum non nocere or Gardner’s rule 23 “use the smallest needle necessary to get the job done”
25 Gauge
22 Gauge
Aspirating knees with 18 gauge easier for physician but potentially more painful and injurious for patient
18 Gauge
18 gauge in articular cartilage
John Clark, MD, PhD

21. New ways of doing procedures
Dual Injector
Three Way Stop Cock
Simkin Method
Simkin 3 way stopcock
Dual injector one way valve so as not to mix contents (talk about this in few minutes) will not take a luer lock syringe
RPD developed at U New Mexico better needle control no need to pull back on plunger always pushing to aspirate and to inject
New ways of doing procedures
Reciprocating Procedure Device

22. Which is he best corticosteroid preparation?
Triamcinolone (Aristospan, Kenalog) - easily goes through gauge needles,
Methylprednisone Acetate (Depomedrol) - floculant, may require larger than 30 gauge needle.
Betamethasone Acetate (Celestone Soluspan) - mixture of short and long acting preparation
Dexamethasone Acetate (Decadron-LA) - Long acting, frequently mixed with Decadron for short and long acting combination
Only head to head trial of TCA 20 mg vs MPA 40 mg in knee OA - TCA better pain relief, MPA lasted longer
In 2 small trials of TCA vs MPA in RA, TCA lasted longer
Pyne D, et al Clin Rheumatol 2004;23:

23. Can we mix anesthetic and steroids?
Dogma about not “mixing” local anesthetic with steroids especially methylprednisolone; 74% of us do mix
Preservative parabens may cause steroid to appear flocculant
HPLC study to determine stability of mixed contents for epidural injections
Conclusion: mix away!
Percent drug remaining after time noted by HPLC
Formula 1
Triamcinolone
Bupivicaine
Iohexol
4 hours
93%
101
103
24 hours 97 99
Formula 2
Lidocaine 85 91
Formula 3
Methylprednisolone 88
104 86 98
Formula 4
102 93
Trouble recovering all of steroid as suspension rather than a solution
Do not state whether preservative free
Shat et al. BJ Radiology 2009;82:
Stored at 370

24. Why do patients with acute onset joint effusions keep their joint at of flexion? Boyles Law of course!
Boyles Law: Pressure is inversely proportional to volume when temperature is constant in a closed system pV=C

25. Hochberg et al. Rheumatology 3rd edition
Joint position and intra-articular pressure: Maximum joint volume between of flexion
Hochberg et al. Rheumatology 3rd edition

26. Practice Point: Three causes of severe joint pain
There are three causes of joint pain so severe that the patient will guard the joint and protect against movement
BUGS
BLOOD
CRYSTALS
Patients hold their joint 300 of flexion as this represents maximum joint volume; flexion or extension results in reduced volume thus increased pressure
Slowly developing joint effusions allow time for the capsule to distend and thus do not cause the same degree of pain
BBC Joint

27. Convex vs Concave Joint Surfaces
Electronic Textbook of Hand Surgery
Carpus
Direction
of Needle
Convex
Concave
Radius
Ulna
Radius
Ulna

28. Making your own polarizing microscope

29. Synovial Fluid Findings
Only a small amount
of synovial fluid is
necessary to make
the diagnosis of
crystalline forms of
arthritis; important to crystal prove at least once

30. Scope and Kit

31. Placing Polarizer and Analyzer

32. Crystals

33. Shoulder
Subacromial Region

34. Shoulder Anatomy Osseous structures Scapula Scapular spine Acromium
Glenoid
Coracoid
Clavicle
Humerus

35. Shoulder Anatomy Important muscles Important joints Other Deltoid
Rotator Cuff
Scapular stabilizers
Important joints
Glenohumeral
Acromioclavivular
“Scapulothoracic”
Other
Redundant capsule
Subdeltoid bursa

36. Glenohumeral Joint: Circle of Stability
Long head of
biceps tendon
Note pear shaped glenoid that allows humeral head to be depressed by RTC muscles

37. Shoulder Joint Capsule
Capsule distended
Grays Anatomy

38. External rotation view
Suggested X-rays:
Internal rotation
External rotation
Axillary view
External rotation view
Axillary view
Mike Richardson, M.D.

39. Dx in 101 Patients with Shoulder Pain Over 18 Months in Internal Medicine Clinic
Diagnosis Percent
Rotator Cuff Disease 62
Myofascial Pain 22
Adhesive Capsulitis 10
AC Joint OA 4
Bicepital Tendonitis 3
RA/OA/RSD/PMR 1 each
Anderson, Kaye. West J Med 1983; 138:268

40. Neer CS, 2d. Impingement lesions. Clin Orthop 1983; 173:70
Impingement Syndrome
Impingement is caused by compression of the rotator cuff tendons and subacromial bursa between the greater tubercule of the humerus and the lateral edge of acromion; direct trauma vs impairment of blood supply?
3 stages of impingement syndrome described by Neer
Stage 1 - Edema and hemorrhage
Stage 2 - Cuff fibrosis, thickening, and partial cuff tearing
Stage 3 - Full thickness tendon tears, bony changes, and tendon rupture.
Neer CS, 2d. Impingement lesions. Clin Orthop 1983; 173:70

41. Posterolateral Injection of the Subacromial Space
Behind humeral head, under the acromium, directed toward the AC joint
25 gauge, 1 1/2 inch needle
Anesthesia with 3-4 cc 1-2% lidocaine useful as diagnostic test
Inject with 2 cc bupivicaine & mg of depomedrol or triamcinalone

42. Lateral Subacromial Injection
Palpate AC joint
Identify acromion
1 cm below acromion; angle under AC joint

43. Subacromial Injection: Lateral vs Posterolateral

44. Note how patient is elevating arm?

45. Injection + exercise vs exercise alone for RTC tendonitis
227 pts randomized to injection + exercise vs exercise alone for impingement syndrome; mean 16 wks of pain
20 mg of triamcinolone plus lignocaine
Exercise individualized; attended as many PT sessions as necessary
Outcome:
1 & 6 wks pain/disability scores significantly better for injection
At 12 & 24 wks NO difference between groups
At later assessments, exercise only group taking more pain meds & 32% were injected at some time between 12 and 52 wks
Conclusion:
Injection therapy provides early pain improvement in impingement syndrome
One-third of exercise only patients go on to injection
Crawshaw et al BMJ 2010

46. Do repeated injections lead to RTC tears?
230 patients who had had an MRI scan for impingement symptoms retrospectively evaluated for frequency of RTC tears by number of subacromial steroid injections
128 had 0-2 injections, 102 had 3 or more
Exclusions: age > 70, trauma, RA, Diabetes
Results:
Conclusion: repeated injections NOT associated with RTC tears
More full thickness tears in fewer injection group??
0-2 injections
3 or more
RTC tears
65 (50.8%)
48 (47%)
Partial thickness 12 21
Full thickness 50 24
Massive tear 3
Ann R Coll Surg Engl 2009; 91: 414–416

47. Does a corticosteroid injection help in adhesive capsulitis and if so does it matter where we put it?
191 pts with adhesive capsulitis randomized to 4 groups; all received progressive PT
Subacromial steroid injection (40 mg TCA)
Glenohumeral steroid injection
Combination injection using same total steroid dose
NSAID
At 16 weeks steroid groups significantly less pain and improved motion compared to NSAID only
At 24 weeks no difference b/w groups
Did not matter where the steroid was placed (US guided)
Shin SJ, Lee SY. J Shoulder Elbow Surg 2013;22:

48. Knee

49. Knee anatomy Important points:
Synovial space extends above patella; large target
Synovial space posterior to knee joint as well; may explain why patients have posterior pain with an effusion
Gray’s Anatomy

50. Menisci
Bursae
ACL PCL
Infrapatellar Fat Pad
Menisci
Joint Capsule

51. Shape of Patella Femoral Condyles Note “keel” of the patella
Patella, Lateral
Shape of Patella
Patellar Groove
(Femoral Sulcus)
Axial View of Knee
Visible Human
Femoral Condyles
MultiMedia Group, used with permission
Note “keel” of the patella
Purpose of patella?

52. Lateral
Medial
Suprapatella

53. Lateral
Medial

54. Lateral
Medial

55. Lateral
Medial
Note tissue thickness medial vs lateral

56. Lateral
Medial
Note ridge on lateral femur
Midpatella

57. Lateral
Medial
Note concave v convex relationship of PFJ

58. Lateral
Medial

59. Reasons to aspirate or inject a knee
Confirm inflammatory arthritis/crystalline arthritis
R/O septic arthritis (knee most affected joint)
Relieve pressure in OA/inflammatory arthritis
Inject
Treat inflammatory arthritis with IA steroids
Inject steroids/hyaluronic acid for OA
Equipment
21-22 gauge needle for aspiration (18??)
25 gauge to inject only
20-40 mg of triamcinolone or depomedrol
Like celestone soluspan for gouty arthritis when available

60. Knee approaches
There are at least 4 different routes utilized to enter the knee joint
Medial mid-patellar
Lateral supra-patellar
Anteromedial or anterolateral
Lateral mid-patellar
Each route has their proponents but it is important to be be familiar with several as some patients will not be easily approached via your most comfortable route

61. Medial knee approach
Medial approach is particularly useful when there is a small effusion
Identify the superior and inferior poles of the patella
Mark a location 1/3-1/2 down from the superior pole and just below the medial margin of the patella
Angle needle slightly inferior and a bit superior to miss the patellar keel
Make sure you look at the patient’s foot; the needle should be generally perpendicular to the foot
Courtney & Doherty: Best Practice & Research Clinical Rheumatology. 2009

62. Superolateral knee approach
This approach is useful for large effusions
Mark the area where the superior and lateral margins of the patella meet
Angle the needle down and medially into the joint space
Courtney & Doherty: Best Practice & Research Clinical Rheumatology. 2009

63. Anterior approaches for knee injections
Patella
This approach can be done from either the medial or lateral surface
Identify the patellar ligament then the tibial plateau
Generally there is a “soft spot” that identifies the area adjacent to the ligament and just above the tibial plateau
Angle the needle toward the center of the knee
Medial edge of patellar ligament
Tibial plateau

64. Anterior approach “Soft spot” Needle directed toward center of knee
Not recommended for aspiration

65. Lateral Midpatellar Approach
Remember MRI scan
Suggest inserting needle no further than 1/2 the way down the lateral patellar margin
Tissue to traverse is thin laterally and can use 1” needle in normal sized person
John Clark is using butterfly needle in this picture
John Clark MD, PhD

66. Bilateral knee effusions
Note loss of medial concavity and bulging suprapatellar pouch

67. Anesthesia with 1-2% lidocaine without epinephrine (what is wrong with this picture?)
Note marks on knee

68. Aspiration with 21-22 gauge needle and 20-30 cc syringe

69. Using mosquito clamp to change from aspiration to injection syringe

70. Injecting with 40 mg of triamcinolone or depomedrol +/- mixed with small amount of local anesthetic

71. Clean, bandage, bed rest x 24 hr

72. Jackson et al. JBJS 2002;84-A:1522-27
Accuracy of knee injection into non-effused joints by location of injection
240 knee injected for OA done by one orthopaedic surgeon into knees without effusions
Three approaches; anteromedial, anterolateral, and lateral mid-patellar
Placement of injected material confirmed by fluoroscopy
Accuracy:
Anteromedial: 60/80 in joint space (75% accuracy)
Anterolateral: 57/80 in joint space (71% accuracy)
Lateral mid-patellar: 74/80 in joint space (93% accuracy)
Jackson et al. JBJS 2002;84-A:

73. Aspirate or not aspirate RA knee before steroid injection?
191 swollen RA knees randomized to receive 20 mg of triamcinolone following:
Complete aspiration of fluid
No aspiration of fluid
Followed 6 mo primary end point recurrent knee swelling
Groups balanced with regard to gender, medications, prednisone use, ESR etc.
Primary end point:
Relapses in 23% of aspirated knees
Relapses in 47% of non-aspirated knees (p = .001)
Medications changed in similar % of pts during study period
Weitoft & Uddenfeldt. Ann Rheum Dis 2000; 59:233

74. Should an RA knee be rested following injection?
Old dogma: bed for 2-3 days and then use crutches for 2-3 wks
Chakravarty et al Br J Rheum 1994
Randomized 91 Pts with inflammatory knee arthritis to 24 hr of in hospital rest or usual activity after 40 mg of triamcinolone hexacetonide & 2 cc of lignocaine in knees aspirated to dryness
VAS pain, knee circumference, 50 foot walk time, CRP followed at 3, 6, 12 and 24 months
Results - both improved at 3 wks; RG showed highly significant improvement through 24 wks compared to NRG in all of the study variables; 8 NRG & 2 RG Pts required reinjection
Conclusion - 24 hr of bed rest improves clinical outcome for inflammatory arthritis patients (OA pts as well?)

75. Conclusion
Make sure our patients are well informed about the procedure process
If unsure, review basic anatomy before procedure
Be careful but remember that serious adverse events are very rare
Evidence based approach will hopefully turn a “wild west” approach to arthrocentesis and injection into a more orderly process!