1. Primary Care Approach to Knee Pain
Bradley Sandella, DO, ATC
Director of Sports Medicine
Sports Medicine Fellowship Program Director

2. Goals of Lecture
Be able to identify the most common causes of knee pain.
Demonstrate several examination techniques to identify different causes of knee pain.
Design a Home Exercise Program for knee pain

3. Epidemiology of Knee Pain
Accounts for approximately 1/3 of musculoskeletal complaints seen in the primary care setting.
5-10% of all visits
With 25% being anterior knee pain
Females more commonly get it than males
As many as 54 % of athletes have some degree of knee pain each year
25% of all runners will experience

4. Doc....my knee hurts

5. Most Common Causes of Knee Pain in Primary Care
Osteoarthritis (34%)
Meniscal injury (9%)
Collateral ligament injury (7%)
Cruciate ligament injury (4%)
Gout (2%)
Fracture (1.2%)
Undifferentiated causes including sprains and strains (42%)
Jackson J, O’Malley P, Kroenke K, “Evaluation of Acute Knee Pain in Primary Care”, Ann Intern Med 2003; 139(7):

6. Anatomy Anterior Patella Posterior facets Medial Alignment
Patella Tendon
Tibial Tubercle
Bursas
Posterior
Gastrocnemius
Popliteal vessels
Medial
Medial collateral ligament
Medial meniscus
Lateral
Lateral collateral ligament
Lateral meniscus

7. Anatomy Internal structures Ligaments Cartilage
Anterior cruciate ligament
Posterior cruciate ligament
Medial collateral ligament
Lateral collateral ligament
Cartilage
Menisci
Articular

8. History Mechanism Acute vs. chronic pain Unilateral vs. bilateral
Swelling / effusion
Worse with activity vs. prolonged sitting
Stairs
Mechanical symptoms
Giving way
Locking / catching

9. It hurts right here……in the front

10. Anterior knee pain Children / adolescent Adult
Patellofemoral pain syndrome
Patella subluxation
Patella tendinitis
Tibial apophysitis
Adult
Osteoarthritis
Pes anserine bursitis
Gout
Inflammatory arthropathy
Septic joint

11. Patellofemoral Syndrome
Also referred to as Anterior knee pain or Idiopathic anterior knee pain or chondromalacia patella
Retropatellar or peripatellar pain
Results from stresses upon patellofemoral joint

12. Epidemiology Leading cause of knee pain < 45 y/o Females > males
25-40% of all knee pain in sports clinics

13. Anatomy Patella is sesamoid within quadriceps tendon
Articulates with trochlear groove of femur

14. Predisposing anatomy Increased Q angle Miserable malalignment
VL>VMO muscle imbalance
Decreased flexibility

15. History Chronic anterior knee pain Often bilateral
Usually no history of acute injury
Often unable to point to one spot
Worse with activity
Often worse with stairs
Often worse with prolonged sitting

16. Exam Observe active knee extension: Flexibility testing
Lateral tracking
Patellar tilt
Patella mobility
Tight retinaculum
Q angle
Flexibility testing
Strength testing
Single leg squat
Special testing
Patella apprehension
Patellar compression
Clark’s Inhibition test

17. Patellar Apprehension
Knee flexed to 30 deg and relaxed across thigh
Force patella laterally with thumbs
OBSERVE FACE – notice apprehension or discomfort before actual dislocation

18. Patellofemoral Compression Clarke’s test
Knee in full extension and relaxed
Contract quad, ask about pain, relax quad
Perpendicular pressure around superior patella
with web space between thumb-index
Re-contract quad
Positive test = pain

19. Single Leg Squat

20. Should I order imaging?
X-ray
Ottawa Knee Rules
MRI
MRI arthrogram

21. But as in life….you have options
Ottawa Knee Rules
Pittsburgh Decision Rules
Age 55 or over;
Isolated tenderness of the patella;
Tenderness at the head of the fibula;
Inability to flex to 90 degrees;
Inability to walk four weight-bearing steps both immediately and in the emergency department.
Efficacy : Sensitivity: 97% Specificity: 27% Reduced the use of knee radiographs by 28%
Blunt trauma or a fall as mechanism of injury plus either of the following:
Age younger than 12 years or older than 50 years
Inability to walk four weight-bearing steps in the emergency department
Efficacy: Sensitivity: 99% Specificity: 60% Reduced the use of knee radiographs by 52%
The Pittsburgh Decision Rules are more sensitive and more specific (1).
Validated - ANNALS OF EMERGENCY MEDICINE 3 8 : 4 OCTOBER 2001
Tandeter HB, Shivartzman P. Acute knee injuries: use of decision rules for selective radiograph ordering. Am Fam Physician. 1999:

22. X-ray
Check for:
lateral subluxation
Patella tilt
Degenerative changes

23. How about an MRI?
American Academy of Orthopaedic Surgeons 2011 Annual Meeting: Abstract 299. Presented February 17, 2011.
33 patients (31%) underwent MRIs
18 scans (55%) were classified as unnecessary because it was possible to make the diagnosis with history, physical examination, and X-rays alone.
Of the remaining 75 patients (69%) who presented without an MRI study
only 4 required additional MRI evaluation, for a tentative diagnosis of a meniscal tear in 3 patients and osteonecrosis in 1 patient
The most common final diagnosis for this cohort was osteoarthritis in 41 patients (38%), followed by patellofemoral syndrome in 14 patients (13%) and meniscal tears in 8 patients (7%).
the diagnosis could be established using plain X-rays alone,
the patient had patellofemoral pain with a normal ligamentous and meniscal exam,
the patient's knee pain resolved before he or she was seen by an orthopedic surgeon, or
the MRI findings had no effect on treatment outcome.

24. Treatment
Physical Therapy
Modalities
Alternative
Surgery

25. Physical Therapy Strengthen VMO
Closed chain exercises
Hip abductor/external rotator strengthening
IT band/ hamstring flexibility

26. Other modalities Taping Bracing Corticosteroid injection
Widely employed, multiple trials have shown not significant benefit*
McConnell taping
Bracing
No good data to demonstrate benefit
Patella stabilizing brace
Palumbo knee brace
Corticosteroid injection
* Aminaka N, Gribble, PA. A Systematic Review of the Effects of Therapeutic Taping…. J. of Athl Train: 2005

27. Alternative treatments
Acupuncture
In randomized study, placebo group showed equal benefit
Benefit at four weeks
Chiropractic patellar mobilization
No statistical improvement
Manipulation
Decreased quadriceps inhibition

28. Referral to Specialist
Conservative Trial Fails- 4-6 weeks
Effusion associated w/ AKP
Important to Answer before referral
Is Pain Reflex Inhibition gone?
Is there evidence of VMO hypertrophy? If no, compliance issues must be addressed.

29. Surgical intervention
Lateral release
17-92% pt satisfaction
Tibial tubercle advancement
Vastus Medialis transposition
Microfracture procedures for chondromalacia

30. It is not so much pain…..but more of an unsteady felling

31. Knee instability Ligament sprain Meniscal tear Reflexive pain arc
Osteoarthritis
Loose body
Osteochondral defect
Osteochondritis desiccants

32. Statistics 100,000 ACL injuries a year
Female athletes at 2-8 times increased risk for ACL injury than male athletes in comparable sports
Women experience ACL tears up to nine times more often then men.
American Family Physician; 2010
Non contact and contact mechanisms are different
70% of ACL injuries are the result of non-contact situations

33. Anatomy and Function Anatomy Function 2 bundles
Runs from the anterior intercondyle region of the tibia to the medial aspect of the lateral condyle of the femur
Function
Maintain rotary stability
Prevent anterior tibial translation on the femur

34. Anatomy and Function Anatomy Function
Crescent-shaped pads of fibrocartilage located between the femoral condyles and the tibial plateaus
Function
Aid in dissipating loading forces placed on the knee
stabilizing the knee during rotation
lubricating the knee joint
Medial - Larger
Less movement

35. Mechanism of Injury Three non-contact ACL injury mechanisms
Cutting
Deceleration
Landing
Non-contact injury will often occur with jumping or landing from a jump

36. Theories Neuromuscular Anatomy Hormonal Extrinsic factors
Hamstring strength
Proprioception
Muscular activation
Biomechanical dynamics
Anatomy
Femoral notch width
Q angle
Hormonal
Estrogen receptors on the ACL
Extrinsic factors

37. One plausible cause Dynamic Neuromuscular Imbalance
Women run, land, and jump differently
Female athletes land with greater maximal valgus angle*
Significant differences between dominant and non-dominant knees*
Female athletes rely less on hamstring and more on quadriceps and gastrocnemius++
Upon landing, women tend to land with less knee flexion*
* Mandelbaum BR et al. Effectiveness of a Neuromuscular and Proprioceptive Training …Amer Journal of Sports Medicine
++ Harmon KG, Ireland ML. Gender differences in noncontact anterior cruciate ligament injuries. Clinics in Sports Medicine

38. History Acute injury Unilateral Immediate Pain – often
Diffuse swelling – occurring 1-2 hours after activity
Popping – audible or felt
Instability – knee giving way
Catching / locking

39. Special Tests for Ligaments
ACL
Lachman
87% sensitive / 93 % specific
Anterior Drawer
48% sensitive / 87% specific
PCL
Posterior Drawer
Sag/ Gravity Test
MCL
Valgus 0&30
LCL
Varus 0&30
Jackson J, O’Malley P, Kroenke K. Evaluation of Acute Knee Pain in Primary Care. Ann Intern Med: 2003; 139(7):

40. Special Tests for Menisci
McMurray
52% sensitive / 97% specific
Apley Grind
Flick
Several studies have concluded that a negative physical exam can reliable exclude meniscal pathology
Jackson J, O’Malley P, Kroenke K. Evaluation of Acute Knee Pain in Primary Care. Ann Intern Med: 2003; 139(7):
Ellis M, Meadows S, “For knee pain, how predictive is physical examination for meniscal injury?”, J Fam Pract 2004; 53(11)

41. Radiology
X-ray
Often normal
Effusion
Segond Fracture

42. Radiology MRI Torn ligament Loss of PCL arc Bone bruising
Wavy appearance
Complete void
Loss of PCL arc
Bone bruising
Lateral femoral condyle and tibial plateau

43. Radiology MRI Linear density change Extruded tissue
Intra-substance, horizontal, or vertical
High degree injury if tear involves travels to joint surface
Extruded tissue
sensitivity and specificity
91.4% and 81.1% - medial meniscal tear
76% and 93.3% -lateral meniscal tear
Crawford R, Walley G, Bridgman S, Maffulli N. Magnetic resonance imaging versus arthroscopy in the diagnosis of knee pathology, concentrating on meniscal lesions and ACL tears: a systematic review. Br Med Bull. 2007

44. Treatment for an ACL Injury
Surgery
Athletes and active women
Mechanical symptoms
Graft selection
Autograph – patella tendon vs. hamstring
Allograph
Non-invasive
Physical therapy
Bracing

45. Physical Therapy Strength training Flexibility Proprioception
Quadriceps – hamstring ratio
Flexibility
Quadriceps and hamstring
Proprioception

46. Bracing? No evidence that pain, range of motion, graft stability,
or protection from subsequent
injury were affected by brace use.
Bracing after ACL Reconstruction: A Systematic Review. Clinical Orthopaedics and Related Research

47. Prevention
Proper training – proprioception and neuromuscular training exercises
Decelerate in a more controlled fashion by taking smaller steps than one sudden step
Round off turns when pivoting, keeping legs inside body shape
Concentrate on core strength

48. Prevention Prevention programs Prevent Injury, Enhance Performance
Aim of program
Diminish the effect of fatigue on neuromuscular control
88% reduction in ACL injuries*
FIFA 11+
Complete warm-up to prevent ACL injuries
* Mandelbaum BR et al. Effectiveness of a Neuromuscular and Proprioceptive Training Program in Preventing Anterior Cruciate Ligament Injuries in Female Athletes: 2-year follow-up. American Journal of Sports Medicine ; 33(7):

49. Long-term Sequelae
Osteoarthritis in up to 90% of patients after a previous ACL

50. Treatment for a Meniscal Injury
Non-surgical consideration
Surgical consideration
Symptoms develop over 24 to 48 hours after the acute injury
Able to bear weight
Minimal swelling
Knee has full range of movement with pain only at or near full flexion
Pain on McMurray testing occurs only with deep knee flexion
MRI demonstrates small intra-substance and vertical tears
After a severe twisting injury, activity could not be resumed
Locked or restricted motion
Pain after minimal flexion in McMurray testing
An associated ACL tear
Little improvement after 3 weeks of non-invasive treatment
MRI demonstrates a large complex meniscal tear
Cooper, R, Crossley, K, Morris, H.. Acute knee injuries. In: Clinical Sports Medicine, 2nd edition, Brukner, P, Khan, K (Eds), 2000

51. Physical Therapy Strength training Flexibility Proprioception
Quadriceps – hamstring ratio
Flexibility
Quadriceps and hamstring
Proprioception

52. Surgery Surgical options Approach Partial or total meniscectomy
Partial meniscectomy is preferred method considering speed of recovery and functional outcome
Repair of the meniscal tear
Approach
Arthroscopic
Open

53. Chronic Degenerated Meniscal Injury
Medial meniscectomy in patients over the age of fifty: a six year follow-up study
20% of good results after a degenerative meniscal tear
Ménétrey J, Siegrist O, Fritschy D. Medial meniscectomy in patients over the age of fifty: a six year follow-up study. Swiss Surg. 2002;.

54. Chronic Degenerated Meniscal Injury
A Randomized Trial of Arthroscopic Surgery for Osteoarthritis of the knee
Arthroscopic surgery for osteoarthritis of the knee provides no additional benefits to optimized physical and medical therapy
Kirkley A, et al. A Randomized Trial of Arthroscopic Surgery for Osteoarthritis of the Knee. The New England Journal of medicine

55. In Conclusion
Patellofemoral is a very common problem. An accurate diagnosis and aggressive treatment plan can be helpful to patients.
ACL injuries can be devastating but we may have some ways to help prevent the injury from occurring
Not all meniscal injuries need surgery

56. References
American Academy of Orthopaedic Surgeons 2011 Annual Meeting: Abstract 299. Presented February 17, 2011.
Aminaka N, Gribble, PA. A Systematic Review of the Effects of Therapeutic Taping on Patellofemoral Pain Syndrome. Journal of Athletic Training: 2005
Calmbach W, Hutchens M. Evaluation of Patients Presenting with Knee Pain: Part I. History, Physical Examination, Radiographs, and Laboratory Tests. Am Fam Physician: 2003; 68(5).
Calmbach W, Hutchens M, “Evaluation of Patients Presenting with Knee Pain: Part II. Differential Diagnosis”, Am Fam Physician 2003; 68(5).
Crawford R, Walley G, Bridgman S, Maffulli N. Magnetic resonance imaging versus arthroscopy in the diagnosis of knee pathology, concentrating on meniscal lesions and ACL tears: a systematic review. Br Med Bull. 2007;84:5.
Cooper, R, Crossley, K, Morris, H.. Acute knee injuries. In: Clinical Sports Medicine, 2nd edition, Brukner, P, Khan, K (Eds), McGraw-Hill, p.426
Ellis M, Meadows S. For knee pain, how predictive is physical examination for meniscal injury?” J Fam Pract 2004; 53(11).
Harmon KG, Ireland ML. Gender differences in noncontact anterior cruciate ligament injuries. Clinics in Sports Medicine, vol. 19, no. 2, pp. 287–302, 2000.

57. References
Jackson J, O’Malley P, Kroenke K. Evaluation of Acute Knee Pain in Primary Care. Ann Intern Med: 2003; 139(7):
Kirkley A, et al. A Randomized Trial of Arthroscopic Surgery for Osteoarthritis of the Knee. The New England Journal of medicine ; 359(11):
Mandelbaum BR et al. Effectiveness of a Neuromuscular and Proprioceptive Training Program in Preventing Anterior Cruciate Ligament Injuries in Female Athletes: 2-year follow-up. American Journal of Sports Medicine ; 33(7):
Ménétrey J, Siegrist O, Fritschy D. Medial meniscectomy in patients over the age of fifty: a six year follow-up study. Swiss Surg. 2002;8(3):113.
Tandeter HB, Shivartzman P. Acute knee injuries: use of decision rules for selective radiograph ordering. Am Fam Physician. 1999: Dec;60(9):
Wright R, Fetzer G. Bracing after ACL Reconstruction: A Systematic Review. Clinical Orthopeadics and Related Research

58. Increased Q angle Measurement Normal angle
ASIS to mid patella
Mid patella to tibial tubercle
Normal angle
10-20 degrees
Lateral pull leads to abnormal tracking

59. Mechanism of Injury Anatomic Abnormality Repetitive Microtrauma
Malalignment
Muscle imbalance
Compensation
Repetitive Microtrauma
Overuse
Growth spurts in children
Macrotrauma
Contusion
Sprain / strain