Original scientific work presented at ISAKOS meeting 2017 in Shangai

1. Patellofemoral pain and
potential patellar instability
at a long term follow up
Dei Giudici L, Faini A, Coppa V, Belfioretti L, Gigante A

2. DISCLOSURE
None of the Authors have conflict of
interest to declare

3. BACKGROUND
 21-45% of adolescent population suffer from anterior knee pain
 Incidence 8,5% - F:M 2,23:1
 Up to 74% of the disability in the young active population
 MULTIFACTORIAL etiology (ischemic, malalignment, neuronal theory)
Chondral degeneration – AKP – Function
Predisposing factors
-Trochlear dysplasia -Excessive femoral version
-Increased TTTG -Excessive tibial rotation
-Abnormal Tilt -Recurvatum
-Patella alta -Valgus
Potential Instability
- At least 1 factor
- No dislocation
Objective Instability
- At least 1 factor
- > 1 dislocation PF Pain Syndrome
- No factors or dislocation

4. METHODS
 AIM: analyze the long term outcomes of patients suffering by
patellofemoral pain that didn’t underwent surgery, in terms of
symptoms progression, CT evidences, Kujala and Tegner score
 DESIGN: prospective, longitudinal, observation
AKP patients
Personal
physician
Our Institute
radiological dpt
(PFJ referral center)
Treatment
continuation with
personal physician
Lyonnese CT scan Exclusion:
- Traumatic injuries
- Dislocations
- Subluxation
- Previous surgeries
FINAL POPULATION:
- Patellofemoral Pain Sdr
- Potential instability

5. METHODS
 DATA GATHERING: demographic, clinical data, CT measurements
(Fulkerson grading, Lateral Patellar Angle, Lateral Patellar Displacement,
Sulcus Angle, TT-TG), Kujala score, Tegner score
 ASSESSMENTS: symptoms progression, CT modifications, Kujala and
Tegner progression, recurrence of NSAID consumption, rehabilitation,
and intrarticular injection
 FU were set at one and ten years
 STATISTICAL ANALYSIS:
 univariate analysis for sample description with means and SDs for
quantitative variable;
 bivariate analysis with t-test for paired data and chi-square test for dicotomic
variable
 ANOVA test
 Statistical significance: 0.05

6. RESULTS
 148 patients identified
 Final population: 92 patients
 Age: 25 yo
 BMI: 22,7
 PFPS: 71 – PPI: 21
 56 exclusion (18 PFPS + 38 PPI) due to surgery after 14 months
0
2
4
6
8
Inclusion 12 months 10 years
PFPS PPI
PAIN
Other clinical
features @ 10y
PFPS PPI
Articular Blocks 1,40% 17%
Metereophaty +8% +16%
Chronic NSAIDs +21% +26%
Cyclic Rehab -20% -21%

7. RESULTS
0
10
20
30
40
50
60
70
80
90
t0 t1 t2
PFPS PPI
KUJALA SCORE
 TEGNER SCORE:4,73,4 @ 10 y
 Documented dislocation: 16% (PPI only)
 No CT modifications after 10 years

8. DISCUSSION
 Patients tend to adapt to their patellofemoral
condition
 Reduction in activities
 Cyclic use of NSAIDs
 Cyclic rehabilitation exercises
 Overtime pain reduction and development of
subjective instability
 Metereopathy (sign of chondral surface
degeneration?)
 Overall good functionality

9. CONCLUSIONS
 Patellofemoral pain sdr and potential patellar instability do
not necessarily require a surgical treatment
 Patients adapt to their chronic condition
 NSAIDs and specific rehab exercise can help during acute
phases
 A more careful approach should be reserved for PPI patients

10. ESSENTIAL BIBLIOGRAPHY
Lindberg (1986) The patellofemoral pain syndrome. Thesis, Linkoping University, Linkoping Sweden
Boling, Padua, Marshall, Guskiewicz, Pyne, Beutler. Gender differences in the incidence and prevalence
of patellofemoral pain syndrome Scand J Med Sci Sports. 2010 October ; 20(5): 725–730.
doi:10.1111/j.1600-0838.2009.00996.x.
Blond , Hansen . Patellofemoral pain syndrome in athletes: a 5.7-year retrospective follow-up study of 250
athletes. Acta Orthop Belg. 1998; 64(4):393–400.
Fairbank , Pynsent, van Poortvliet, Phillips. Mechanical factors in the incidence of knee pain in
adolescents and young adults. J Bone Joint Surg Br. 1984; 66(5):685–693.
Witvrouw , Lysens, Bellemans, Cambier, Vanderstraeten. Intrinsic risk factors for the development of
anterior knee pain in an athletic population. A two-year prospective study. Am J Sports Med. 2000;
28(4):480–489. [PubMed: 10921638]
Sanchis – Alfonso 2013. Pathophysiology of anterior knee pain. Patellofemoral Online Education ISAKOS
Dye et al(1999) The mosaic of pathophysiology causing patellofemoral pain: therapeutic implications.
Operative Techniques in sports Medicine 7:46-54
Powers, Mechanisms Underlying Patellofemoral Pain: Lessons Learned over the Past 20 Years. ISAKOS
Educational