Assessing functional mobility in survivors of lower-extremity sarcoma: reliability and validity of a new assessment tool.
BACKGROUND
Reliability and validity of a new tool, Functional Mobility Assessment (FMA), were examined in patients with lower-extremity sarcoma. FMA requires the patients to physically perform the functional mobility measures, unlike patient self-report or clinician administered measures.


METHODS
A sample of 114 subjects participated, 20 healthy volunteers and 94 patients with lower-extremity sarcoma after amputation, limb-sparing, or rotationplasty surgery. Reliability of the FMA was examined by three raters testing 20 healthy volunteers and 23 subjects with lower-extremity sarcoma. Concurrent validity was examined using data from 94 subjects with lower-extremity sarcoma who completed the FMA, Musculoskeletal Tumor Society (MSTS), Short-Form 36 (SF-36v2), and Toronto Extremity Salvage Scale (TESS) scores. Construct validity was measured by the ability of the FMA to discriminate between subjects with and without functional mobility deficits.


RESULTS
FMA demonstrated excellent reliability (ICC [2,1] >or=0.97). Moderate correlations were found between FMA and SF-36v2 (r = 0.60, P < 0.01), FMA and MSTS (r = 0.68, P < 0.01), and FMA and TESS (r = 0.62, P < 0.01). The patients with lower-extremity sarcoma scored lower on the FMA as compared to healthy controls (P < 0.01).


CONCLUSIONS
The FMA is a reliable and valid functional outcome measure for patients with lower-extremity sarcoma. This study supports the ability of the FMA to discriminate between patients with varying functional abilities and supports the need to include measures of objective functional mobility in examination of patients with lower-extremity sarcoma.
Marchese
Victoria G
VG
Department of Epidemiology and Cancer Control, St. Jude Children's Research Hospital, Memphis, Tennessee 38105-2794, USA. vgocha@mindspring.com
Rai
Shesh N
SN
Carlson
Claire A
CA
Hinds
Pamela S
PS
Spearing
Elena M
EM
Zhang
Lijun
L
Callaway
Lulie
L
Neel
Michael D
MD
Rao
Bhaskar N
BN
Ginsberg
Jill P
JP
D000671:Amputation, Surgical; D001859:Bone Neoplasms / Q000188:drug therapy / Q000532:radiotherapy / Q000601:surgery; D002183:Canes / Q000706:statistics & numerical data; D003131:Combined Modality Therapy; D003446:Crutches / Q000706:statistics & numerical data; D051341:Dependent Ambulation / Q000523:psychology / Q000706:statistics & numerical data; D006801:Humans; D007866:Leg / Q000503:physiopathology / Q000601:surgery*; D051346:Mobility Limitation; D015588:Observer Variation; D010146:Pain / Q000453:epidemiology / Q000209:etiology; D010549:Personal Satisfaction; D010807:Physical Endurance; D005082:Physical Exertion; D011183:Postoperative Complications / Q000453:epidemiology* / Q000503:physiopathology / Q000523:psychology; D015203:Reproducibility of Results; D012420:Running; D012509:Sarcoma / Q000188:drug therapy / Q000532:radiotherapy / Q000601:surgery*; D012720:Severity of Illness Index; D012917:Social Adjustment; D013177:Sports; D017741:Survivors / Q000523:psychology*; D016138:Walking; D014910:Wheelchairs / Q000706:statistics & numerical data