Clinical calculator
AOFAS Lesser Toes Calculator
AOFAS Lesser Toes Metatarsophalangeal-Interphalangeal Scale
The AOFAS Lesser Toes Metatarsophalangeal-Interphalangeal Scale is a 100-point clinician-administered rating of the second to fifth toes that combines 40 points for pain, 45 for function across six items and 15 for alignment — used to report surgery for hammer, claw and mallet toes, although the society that published it withdrew its endorsement in 2011 because it was never validated.
What the AOFAS Lesser Toes score means
AOFAS Lesser Toes scores run from 0 to 100, where a higher score is better. The bands below are conventional reporting categories, not diagnostic cut-offs.
- Poor0–69
These four grades are a convention that grew up in the literature; the authors defined no severity categories, and no minimal clinically important difference has been established for this scale.
- Fair70–79
- Good80–89
- Excellent90–100
How the score is calculated
Stated in full so the calculation can be independently checked, and reproduced by hand if needed.
The eight items are scored independently and added to a maximum of 100. Pain contributes 40 points (none 40, mild and occasional 30, moderate and daily 20, severe and almost always present 0). Function contributes 45 points across six items: activity limitation 0–10, footwear requirements 0–10, MTP joint motion 0–10 (75° or more 10, 30° to 74° 5, under 30° 0), IP joint motion 0 or 5 (under 10° scores 0), MTP-IP stability 0 or 5, and callus 0 or 5. Alignment contributes 15 points (good 15, fair 8, poor 0). A higher total is better. Five of the items — MTP motion, IP motion, stability, callus and alignment — require a physical examination, so 40 of the 100 points cannot be obtained from the patient alone. Grades of excellent, good, fair and poor at 90, 80 and 70 are a convention that arose in the literature rather than part of the original publication, and no minimal clinically important difference has been established.
Missing data
There is no imputation rule. Every item must be assessed for the total to be valid, and a total reported with items missing is not comparable with a complete score or with published series. Unanswered items contribute zero in the calculator above, which understates the score — a partial figure is shown only so the entry can be checked, and must not be graded.
Instrument profile
- Developer
- Harold B. Kitaoka, Ian J. Alexander, Robert S. Adelaar, James A. Nunley, Mark S. Myerson and Michael Sanders
- Institution
- American Orthopaedic Foot and Ankle Society, United States
- First published
- 1994
- Custodian
- American Orthopaedic Foot and Ankle Society, which formally withdrew its endorsement of its clinical rating systems in 2011
- Items
- 8
- Response format
- Eight fixed-choice items, of which five are examination findings
- Score range
- 0 to 100
- Direction
- Higher score = better
- Recall period
- Current status at the time of examination
- Completion time
- About 5 minutes
- Age range
- Adults
- Regions
- Foot & Ankle
- Conditions
- Hammer toe, Claw toe, Mallet toe, Lesser metatarsophalangeal joint instability, Metatarsalgia, Fifth toe deformity
- Procedures
- Proximal interphalangeal joint arthroplasty, Proximal interphalangeal joint arthrodesis, Flexor tendon transfer, Weil osteotomy, Plantar plate repair, Minimally invasive fifth toe surgery
- Languages
- English, Spanish, Turkish
- Observer agreement
- Not established by the developers. Reliability has since been examined mainly in translated and culturally adapted versions rather than for the scale as originally published.
- Validity
- Published without the item-generation, weighting or validation work that current standards require; the point weightings were assigned by expert consensus rather than derived from patient data.
- Reliability
- Used to report change after lesser toe surgery, but with no established minimal clinically important difference a change of a given number of points cannot be called meaningful.
- Ceiling effect
- Marked. A painless, well-aligned, stable toe in a patient who wears ordinary shoes scores close to the maximum even when joint motion is limited.
- Floor effect
- Uncommon.
When to use the AOFAS Lesser Toes
Well suited to
- Reading and comparing lesser toe surgery series, some of which report AOFAS lesser toes scores.
- Continuing a long-running series or registry that has collected the scale from the start, where switching measures would break the comparison.
Limitations and poor fits
- Choosing a primary outcome measure for a new study or service — the AOFAS itself withdrew its endorsement in 2011, and validated patient-reported alternatives exist, including the Manchester–Oxford Foot Questionnaire, the FAAM and the FAOS.
- Postal, telephone or electronic follow-up: 40 of the 100 points require a physical examination.
- Judging whether an individual patient has improved meaningfully, since no minimal clinically important difference has been established.
- Scoring the great toe, the midfoot or the ankle and hindfoot, which have their own scales in the same 1994 publication.
AOFAS Lesser Toes compared with other instruments
Instruments measuring a related construct, with the practical difference between them.
| Instrument | Items | Range | What it adds |
|---|---|---|---|
| FAAM | 29 | 0–100 | The FAAM is a 29-item patient-reported questionnaire for musculoskeletal disorders of the leg, foot and ankle that produces two separate subscale scores — Activities of Daily Living from 21 items and Sports from 8 items — each expressed from 0% (unable to perform the listed activities) to 100% (no limitation). |
| FAOS | 42 | 0–100 | The FAOS is a 42-item patient-reported questionnaire adapted from the KOOS that scores foot and ankle problems as five separate subscales — Symptoms, Pain, Activities of Daily Living, Sport and Recreation, and Quality of Life — each from 0 (extreme problems) to 100 (no problems). |
| AOFAS Hallux | 8 | 0–100 | The AOFAS Hallux Metatarsophalangeal-Interphalangeal Scale is a 100-point clinician-administered rating of the great toe that combines 40 points for pain, 45 for function across six items and 15 for alignment — among the most widely reported outcomes after hallux valgus and hallux rigidus surgery, although the society that published it withdrew its endorsement in 2011 because it was never validated. |
| AOFAS Ankle-Hindfoot | 9 | 0–100 | The AOFAS Ankle-Hindfoot Scale is a 100-point clinician-administered rating combining 40 points for pain, 50 for function across seven items and 10 for alignment — and although it remains the most-reported outcome in the foot and ankle literature, the society that published it withdrew its endorsement in 2011 because it was never validated. |
Copyright and permitted use
Published openly because it is the question every clinician and researcher asks before using an instrument, and almost nobody answers it.
A clinician-administered rating method published in full in the peer-reviewed literature in 1994, reproduced throughout the foot and ankle literature with no licensing programme. No licence is required. Note that the publishing society has since withdrawn its endorsement of the scale — a scientific caveat rather than a legal restriction, but one that should carry more weight than the licence status when choosing an outcome measure.
References
- Kitaoka HB, Alexander IJ, Adelaar RS, Nunley JA, Myerson MS, Sanders M. Clinical rating systems for the ankle-hindfoot, midfoot, hallux, and lesser toes. Foot and Ankle International. 1994.doi:10.1177/107110079401500701
- Pinsker E, Daniels TR. AOFAS position statement regarding the future of the AOFAS Clinical Rating Systems. Foot and Ankle International. 2011.
Editorial status
Not yet reviewedQueued for clinical review by Sam Tuffun, PT, DPT. Sign-off has not taken place — this is a placeholder assignment, not a completed review.