Long-term prognosis and impact of Osgood-Schlatter disease 4 years after diagnosis: a retrospective study

Key points

1. 0160.5% of respondents still had OSD-related knee pain at follow-up, despite OSD usually being described as resolving within 1 to 2 years.
2. 02Among those with ongoing pain, the median symptom duration was 90 months and 42.9% reported daily knee pain.
3. 03People with continuing pain had much lower knee function (KOOS Sports/Recreation 53 vs 85) and lower quality of life (0.71 vs 0.99) than those who were pain-free.
4. 04More people with knee pain had reduced their sports participation, and over a third exercised less than 1 hour per week.
5. 05This was a small retrospective study with a low response rate, so the findings need confirmation in prospective research.

How it was conducted

Design

Retrospective cohort study (Level of evidence 3), single orthopaedic department in Denmark

Participants

Patients diagnosed with OSD between 2010 and 2016, contacted in 2018; 84 invited, 43 responded (12 female, 31 male)

Follow-up

Median 3.75 years from diagnosis (range 2 to 6 years)

Outcomes

Self-reported knee pain, KOOS Sports/Recreation subscale, EQ-5D-3L-Y quality of life, and physical activity

Analysis

Chi-square test for proportions and independent-samples t tests comparing those with vs without knee pain

What they found

• 60.5% (n=26) of the 43 respondents reported OSD-related knee pain at follow-up.
• Median symptom duration in those still in pain was 90 months (IQR, 24-150 months), and 42.9% of these reported daily knee pain.
• Median pain intensity in those with pain was 5 on a 10-cm VAS (IQR, 3-7).
• KOOS Sports/Recreation scores were significantly lower with knee pain than without (53 [95% CI, 42-63] vs 85 [95% CI, 76-94]; P < .001).
• Health-related quality of life was significantly lower with knee pain than without (0.71 [95% CI, 0.57-0.84] vs 0.99 [95% CI, 0.97-1.00]; P < .001).
• 53.8% (n=14) of those with knee pain reduced activity because of pain vs 35.3% (n=6) of those without (P = .23).
• 54.8% (n=17) of males and 75.0% (n=9) of females still had OSD-related knee pain (P = .22).
• Among 15 adults diagnosed with OSD sequelae, 53.3% (n=8) underwent surgery during follow-up and 86.7% (n=13) still had pain at follow-up.

Limitations

• Low response rate (51.2%) raises the risk of response bias, as responders may have been at the worst end of the symptom spectrum.
• Small sample size means some analyses may have been underpowered, and the design was retrospective with no clinical or ultrasonography examination at follow-up to confirm the pain source.
• Some participants were first seen as adults for OSD sequelae, which may affect recall of onset age and earlier painkiller use.
• As a single-center hospital cohort, the findings may not generalize to milder community cases of OSD.

Why it matters

For patients

If you or your child was diagnosed with Osgood-Schlatter disease, be aware that knee pain can persist for years in some cases rather than always disappearing quickly.

For clinicians

Counsel patients with OSD realistically about the possibility of long-term pain and reduced function, and look for ways to keep them physically active rather than simply advising rest until pain subsides.

For readers

This study challenges the common view that Osgood-Schlatter disease is uniformly innocuous and self-limiting, though stronger prospective evidence is still needed.