Table 7 Studies using foot function measures in surgical interventions

Foot Function Index (FFI), 2000

Lin, S [39]

Validation of AOFAS forefoot outcomes of arthrodesis surgery

N: 16 Mean age: 44 (SD=13.96) 8 male

Pre-post surgery

FFI

VAS

Both FFI and AOFAS scores were improved at post surgery.

Dx: Tarsometatarso injury/degenerative arthritis

Follow-up 36 months (24–65 months)

23 items

Conclusion: useful

Location: USA

FFI and AOFAS were applied at pre-surgery and at follow up

3 domains

FFI, 2002

Watson, TS [61]

Validation with VAS pain scale with SF-36 short form in plantar fasciotomy

Group I N (control): 75 Mean age: 46 (range: 20–78) 14 male

Retrospective observational Follow up duration 26.4 months

FFI

VAS

FFI scores were improved.

Group II N (surgery): 46 Mean age: 46 (Range: 25–78) 9 male

Group II filled out FFI and SF-26 at post-surgery only

23 items

FFI scores reflected activities of daily living. SF-36 s cores reflection satisfaction of physical and role model.

Dx: Sub-Calcaneal pain syndrome

Validation with VAS pain scale SF-36 short form

3 domains

Conclusion: useful.

Location: USA

FFI, 2003

Mulcahy, D [56]

Surgery-Reconstruction of the forefoot; FFI scores were used to test if there was correlation with WOMAC, AOFAS HMIP, and AOFAS LMIP.

N: 79 14 male Mean age: 59 (Range: 24–80)

Retrospective observational; Follow up 6yrs.+3 mo (6mo-19 years)

FFI; 23 items; 3 domains

VAS

FFI pain subscale was used to monitor pain in both groups.

Dx: RA forefoot deformity

Conclusion: useful

Mean age of surgery: 52 years (range: 23–79)

Group 1 stable 1^st ray. (no surgery)

Group 2: 1^st ray surgery

Location: Canada

FFI, 2004

Ibrahim T [48]

Surgery- MTP joint replacement; Validation of AOFAS Hallux scale scores with FFI scores from those who did not have surgery and those who had surgery

N: 8, 1 male

Retrospective observational; Follow up for 17 months

FFI

VAS

Correlation observed between the scores of AOFAS and FFI

Mean age: 58 (Range: 51–80)

23 items

Note: AOFAS Hallux scale had not been validated.

Dx. Hallux rigidus

3 domains

Conclusion: useful

Location: UK

FFI, 2004

Vallier, HA [52]

Surgery-Open reduction internal fixation; Correlation of FFI and musculoskeletal function assessment (MFA)

N: 100 60 male

Retrospective observational

FFI

VAS

Scores of FFI and MFA were correlated

Mean age: 32.6 (Range: 13–77)

Follow up 36 months (12–74 months)

23 items

Conclusion: useful

Dx: Talar neck fracture

FFI was applied to N=59 at follow-up

3 domains

Location: USA

FFI, 2005

Taranow, WS [49]

Surgery- metalic hemiarthroplasty: Do FFI scores improve at post-operation

N: 28 17 male

Retrospective observational case review

FFI

VAS

FFI scores from pre to post operation showed significant improvement.

Mean age: 52.9 (Range: 38–71)

Follow 33.4 months

23 items

Conclusion: useful

(3–mo-111mo)

Dx: Hallux rigidus

3 domains

Location: USA

FFI, 2005

Grondal, L [40]

Surgery-Athrodesis vs. Mayo resection of MTP; FFI scores as outcomes

N: 31; 26 male

RCT not-blinded, ANOVA and multiple comparisons

FFI

VAS

FFI scores at post-surgery within groups were improved and there no significant differences between the groups.

Mean age: 54 yrs

23 items

Conclusion: useful

(Range: 33–77)

Resection N=: 16

3 domains

Fusion N=: 15

Dx: RA painful forefoot deformity

Location: Sweden

FFI, 2005

Daniels, TR [62]

Surgery -Free tibular graft; FFI scores were validated with MODEMS and SF-36 short form

N: 28, 13 male

Observational

FFI 21 items (2 items about orthoses were not applicable) 3 domains

Likert

The scores of FFI, SF-36 and MODEMS were demonstrating similar improved outcomes at post-surgery

Mean age: 52 (Range: 22–76)

Follow-up: 36 months (26–52 months)

Conclusion: useful

Dx: Vascularized fibular bone graft

FFI was applied at pre-surgery and at 6 and between 26–54 month post surgery

Location: Canada

FFI, 2005

Lee, S [63]

Surgery -Isolated sesamoidectomy; FFI disability sub-scale validated with VAS pain scale and SF-36 short form

N; 32; 8 male

Retrospective observational

FFI 9 items

VAS

The scores of FFI disability and VAS pain sub-scales were correlated.Conclusion: useful

Mean age: 37.2 (Range: 18–65)

62 month

1 domain: disability scale

Post-op N=: 20

Dx: Hallux alignment

Location: USA

FFI, 2006

SooHoo, NF [64]

Surgery- Any type of foot and ankle surgery; Validating AOFAS, SF-36 and measuring Standard Response Mean (SRM) and effect size (ES)

N: 25; 6 Male

Pre-post surgery FFI was applied at pre-surgery and 6 months post-surgery

FFI

VAS

Of the instruments used, scores of the pain subscale was the only measure reflecting high SRM (−0.83) and ES (−0.86). Therefore, pain is the most important outcome in studies regarding chronic foot and ankle pain.

Mean age: 40 (Range: 21–69)

23 items

Conclusion: useful

Dx: Chronic foot and ankle conditions requiring surgery

3 domains

Location: USA

FFI, 2006

Van der Krans, A [41]

Surgery- Calcaneal Cuboid arthrodesis; Correlation with AOFAS clinical rating index (CRI) of the hind foot

N: 20; 4 Male

Pre-post surgery

FFI-Dutch 15 items

5-point verbal scale

FFI and CRI scores showed significant improvements

Mean age: 55 (Range: 30–66)

Follow-up 25 months (13–39 months)

Pain and function subscales

Conclusion: useful

Dx: Flat foot

FFI was applied at pre-surgery and ad follow-up

Location: Netherlands

FFI, 2006

Harris, M [53]

Surgery- High impact fracture repair; Correlation with Musculoskeletal function assessment (MFA)

N: 76; 45 Male

Pre-post surgery follow up 26 months (24–38 months). FFI was applied at pre-surgery, 6 and 12 weeks and at 6 months by mail, telephone, and was self-administered.

FFI

VAS

High FFI score occurred in those with the worse fractures and external fixation. This is also reflected in MFA scores.

Mean age: 45 (Range: 17–81)

23 items

Conclusion: useful

Dx: distal tibial plafond fracture

3 domains

Location: USA

FFI, 2006

Stegman M [42]

Surgery-Triple arthrodesis; Correlation with AOFAS hind foot scores

N: 81; 38 Male

Pre-post surgery

FFI Dutch

Likert

FFI-5pt and AOFAS hind foot scores improved 89%. However, patient did not perceive the benefit of the procedure.

Mean age: 40.5 (Range: 14–79)

FFI applied at pre-surgery and 1 yr (1–4) post surgery

15 items

Conclusion: useful

Dx: Hind foot disorders

2 domains

Location: Netherlands

FFI, 2007

Jung, HG [45]

Surgery-Fusion of tarso metatarso-joint; Correlation with SF-36, AOFAS

N: 67; 12 Male

Retrospective observational

FFI

VAS

Scores of the FFI, SF-36 AOFAS and VAS pain scale were markedly improved at post-surgery

Mean age: 60.2 (Range: 35–84)

Follow for 40.6 months

23 items

Conclusion: useful

Dx: Non-traumatic osteoarthritis of the tarso-meta-tarso joints

FFI applied at post-surgery

3 domains

Location: USA

FFI, 2008

Vesely, R [43]

Surgery – Tibio Calcaneal arthrodesis; Correlation with ankle-hind foot score

N: 20; 16 Male

Retrospective observational

FFI

VAS

The scores of FFI and ankle hind foot were improved.

Mean age: 58.7 (Range: 23–72)

FFI applied at post-surgery, time unknown

23 items

Conclusion: useful

Dx: Traumatic arthritis of the ankles

Article in Czech with English abstract.

3 domains

Location: Czech Republic

FFI, 2008

Stropek, S [37]

Surgery- arthroscopy

N: 26; 6 Male

Pre-post surgery observational

FFI

VAS

FFI pain scale scores were markedly improved at post surgery in 79% of the patients

Age: male: 45; female: 49

FFI applied at pre-surgery and at 3 month follow-up

Pain scale

Conclusion: useful

Dx: Calcaneal spur

9 items

Location: Czech Republic

FFI, 2008

Schutte, BG [50]

Surgery-Total ankle replacement; pain and function outcome measure

N: 47; 16 Males

Pre-post surgery

FFI-Dutch

Likert

Total scores improved at post–surgery

Mean age: 57.1 (range 37–81)

FFI applied at pre-surgery and at follow up

18 items

Conclusion: useful

Dx: Ankle joint deformity

Duration of follow up 28 months (range 12–67)

Pain and difficulty subscales

Location: Netherlands

FFI, 2008

Ward, CM [57]

Surgery-Reconstruction; Validation of SF 26 with FFI

N: 25; 14 Male

Pre-post surgery

FFI

VAS

At follow up the FFI scores were in the mid-range. The scores for smokers were worse than non-smokers, females were worse than males. FFI activity limitation and disability scores were correlated with SF-36 physical component scores.

Mean age: 15 (Range: 8.7-25)

FFI applied at mean age of 41.5 years after 26.1 yrs follow-up

23 items

Conclusion: useful

Dx: Flexible Cavovarus Charcot Marie-Tooth

3 domains

Location: USA

FFI, 2009

Castellani, C [65]

Surgery-Fixation with cannulation osteosynthesis; Outcomes of an intervention

N: 21; 11 Male

Retrospective observational

FFI

VAS

At follow-up 3 of the 21 (14%) had poor FFI disability scores

Dx: Transitional fracture of distal tibia

FFI was applied at 3.8 yrs after implants removal

23 items

Conclusion: useful

Age 13.7 (1.4)

3 domains

Location: Austria

FFI, 2009

Bonnin, MP [51]

Surgery – Total ankle arthoplasty; Correlations of FAAM (foot and ankle ability measure)

N: 140; 50 Male

Pre-post surgery pre at pre-surgery FAAM and FFI was applied, and also at 53.8 ±29 months (12–125) post- surgery

FFI

VAS

FFI pain scores were no different between OA and RA groups. The FFI scores were improved and were similar to that of FAAM.

Mean age: 60.9 (Range: 26–90)

23 items

Conclusion: useful

Dx: OA: 100 RA: 40

3 domains

Location: France

FFI, 2009

Potter, MQ [54]

Surgery- Intraarticular fracture of the Calcaneus; Correlation with AOFAS hind foot scores

N: 73; 52 Male

Retrospective observational FFI applied at follow up of 12.8 years (5–18.5)

FFI

VAS

Scored of FFI, AOFAS hind foot and Calcaneal scores were correlated.

Dx: Calcaneal fracture

23 items

Conclusion: useful

Location: USA

3 domains

FFI, 2010

Aurich, M [66]

Surgery-Arthroscopic chondrocyte implant; Correlation with AOFAS hind foot scores and Core Scale of the foot and ankle module of the Academy of Orthopedic Surgeon (AAOS)

N: 18; 13 Male

Retrospective observational FFI was applied at pre-arthroscopy and at follow-up, with mean duration of 19 months

FFI 18 items; Pain and function subscales

Likert

FFI scores improved comparable with those of AOFAS results and Core Scale scores

Mean age: 29.2 (SD 10.2 years)

Limitation: Use of FFI measures with caution in individual whose. functional level is better than the level of activities of daily living.

Dx: Osteochondral lesion of talus/tibia

Conclusion: useful

Location:Australia

FFI, 2010

Van der Heide, HJL [59]

Surgery-Correction pes cavo varus; Validation AOFAS lesser toe module

N: 39; 6 Male

Pre-post surgery; FFI applied at pre-surgery and 40 month post-surgery

FFI-Dutch

VAS

FFI pain and function scores improved post-surgery

Mean age: 59 (Range: 29–81)

Conclusion: useful

Dx: RA lesser MTP

23 items

Location: Netherlands

3domains

FFI- Dutch, 2010

Kroon, M [60]

Surgery-Correction pes cavo varus; Validation AOFAS hind foot scale

N: 15; 8 Male

Pre-post surgery FFI applied at pre and 50 month post surgery

FFI-Dutch

Likert

Pain and function scores improved post surgery

Mean age:40 (SD 14)

18 items

Conclusion: useful

Dx: Cavo varus foot deformity

Pain and function subscales

Location: The Netherlands

FFI, 2010

Van Doeselaar, DJ [46]

Surgery-Fusion of MTP; Correlation with VAS pain and satisfaction

N: 62

Pre-post surgery; FFI applied at pre-surgery and 12 month post-surgery

FFI Dutch; 18 items

Likert

FFI-5 pts scores were improved.

2 groups

Dx: H rigidus; N: 27; 9 Male

Conclusion: useful

Mean age: 58 (Range: 42–72)

Dx: H valgus; N: 35; 6 Male

Mean age: 61 (Range: 37–76)

Location: Netherlands

FFI, 2010

Doets, HC [44]

Surgery-Salvage arthrodesis for failed TAA; Correlating with AOFAS and VAS pain scale

N: 18; 4 Male

Retrospective observational FFI applied at follow up, 3–12 years

FFI-Dutch

5 point rating scale

FFI scores improved similar to that of AOFAS, VAS pain, disability and satisfaction measure

Mean age: 55 (Range: 27–76)

15 items

Conclusion: useful

Dx: Failed TAA

Pain and function subscales

Location: Netherlands

FFI, 2010

Niki, H [47]

Surgery-TMT fusion and osteotomy; Concurrent assessment of FFI and SF-36 and Japanese Society for Surgery of the Foot and Ankle Score

N: 30; 1 Male

Pre-post surgery FFI was applied at pre-surgery and at 36 mos follow-up

FFI

VAS

The scores of all instruments were improved at post-surgery.

Mean age: 53.6 (Range: 45–67)

23 items

Conclusion: useful

Dx: RA fore-foot deformity

3 domains

Location: Japan

FFI, 2010

Schlegel, UJ [58]

Surgery-Club foot correctional; Post-surgery foot health assessment

N: 98; 72 Male

Retrospective observational FFI was applied at 8.2 years (0–11.2); Post surgery N: 46 (50%)

FFI

VAS

FFI scores indicated good foot health.

Mean follow-up: 4.5M (Range: 1–68)

23 items

Conclusion: useful

Dx: Club foot

3 domains

Location: Germany

FFI, 2010

Gaskill, T [55]

Surgery- Internal fixation of the instraarticular Calcaneal fracture; Concurrent evaluation with OAFAS hind foot

N: 146; 99 Male

Retrospective observational FFI was applied at post-surgery 8.98 years

FFI

VAS

FFI scores of Group 1 were better than Group 2 at post surgery.

Group 1 <50 yrs; N: 99; 65 male

23 items

Conclusion: useful

Mean age: 36 (Age range)

3 domains

Group 2 >50 years; N: 47; 33 male

Mean age: 58 (Range: 50–84)

Dx: Calcaneal fracture

Location: USA

FFI, 2010

Eberl, R [67]

Surgery- Various surgical techniques were applied; Post surgery outcomes

N: 24; 18 Male

Retrospective observational

FFI

VAS

FFI scores improved in both groups. Group 1 scored better than Group 2.

Mean age: 13.2 (Range: 5–17 yrs)

Follow-up 3.2 years (7 months-8.2 years)

23 items

Limitation: The author stated that use of self-report in instrument in children may result in spurious outcomes, due to their pronounced potential for compensation.

Group 1 <12 years; N: 9; Age : 9.2

FFI applied at follow up

3 domains

Conclusion: useful

Group 2 >12 years; N: 15; Age: 14.6

Dx: Complex ankle injuries

Location: Australia