P. Kannus et al., An outcome study of chronic patellofemoral pain syndrome - Seven-year follow-up of patients in a randomized, controlled trial, J BONE-AM V, 81A(3), 1999, pp. 355-363
Citations number
48
Categorie Soggetti
Ortopedics, Rehabilitation & Sport Medicine","da verificare
Background We determined prospectively the long-term outcomes of nonoperati
ve treatment of chronic patellofemoral pain syndrome,
Methods: Of forty-nine patients in a prospective, randomized, double-blind
study of unilateral chronic patellofemoral pain syndrome in the knee, forty
-five were reexamined seven years after the initial trial of treatment, In
the earlier trial, the short-term (six-month) effects of intra-articular in
jections of glycosaminoglycan polysulfate combined with intensive quadricep
s-muscle exercises were compared with those of injections of a placebo comb
ined with exercises and with those of exercises alone. At seven years, the
follow-up consisted of standardized subjective, functional, and clinical as
sessments and muscle-strength measurements as well as magnetic resonance im
aging, radiography, and bone-densitometry measurements of the knee,
Results: At six months, complete subjective, functional, and clinical recov
ery had occurred in almost three-fourths of the patients and, with the numb
ers available for study, neither significant nor clinically important diffe
rences among the three initial treatment groups were detected. The subjecti
ve and functional parameters showed few changes between six months and seve
n years; almost three-fourths of the patients still had full subjective and
functional recovery at the time of the latest follow-up. However, accordin
g to the physician's clinical evaluation, the number of patients who had no
symptoms on the patellar compression and apprehension tests decreased over
time, from forty-two (93 percent) and forty (89 percent) of forty-five pat
ients at six months to thirty (67 percent) and thirty-one (69 percent) at s
even years; these changes were significant (p = 0.002 and p = 0.023, respec
tively). The number of patients who had crepitation on the patellar compres
sion test increased over time, from twenty-six (58 percent) at six months t
o thirty-six (80 percent) at seven years (p = 0.021), The physician's overa
ll assessment showed a similar trend, with thirty-four patients (76 percent
) having had complete recovery at six months compared with thirty (67 perce
nt) at seven years; however, with the numbers available, this change was no
t significant (p = 0.420), Magnetic resonance imaging, performed for thirty
-seven patients, revealed no abnormalities in twenty-four (65 percent), mil
d abnormalities in four (11 percent), moderate abnormalities (a 25 to 75 pe
rcent decrease in the thickness of the cartilage) in seven (19 percent), an
d overt patellofemoral osteoarthritis in two (5 percent) at seven years.
Conclusions: The seven-year overall outcome was good in approximately two-t
hirds of the patients. However, the remaining patients still had symptoms o
r objective signs of a patellofemoral abnormality.