Squat and smile assessment in predicting healing of lower limb fractures fixed with a SIGN nail

Abstract

Background: Irrespective of the treatment method, union is the ultimate goal of any fracture treatment. However, nowadays, rather than the physician-based clinico-radiological methods, the patient-reported outcome measurements assessing their quality of life and function are gaining much popularity. This is specifically true in the part of the world where the patient needs almost complete degree of hip/knee flexion e for social, cultural, religious or occupational reason(s). The ability to squat can assess the mobility and stability of joints and thus the quality of squatting is a proxy reflection of the functional outcome after fixation of lower limb fracture. Thus, we studied to determine the inter-observer and intraobserver reliability of Radiographic Union Score for Tibia (RUST) and Squat and Smile (S & S) test in clinical photograph. We further calculated the sensitivity and specificity of S & S test in predicting healing of lower limb fracture fixed by intramedullary interlocking nail considering RUST as the gold standard. Methods: This was a retrospective study of prospectively collected data of solid Surgical Implant Generation Network (SIGN) intramedullary interlocking nailing from a single, university-based, high volume tertiary center where 56 consecutive adults with either tibial or femoral shaft fractures fixed with a SIGN nail within one year and not requiring any surgery till minimum of eighteen-month follow-up were included. Cases without either Anterior-Posterior (AP) view and/or Lateral (Lat.) view follow-up x-ray(s) or proper S & S clinical photograph (at least 1.5-year post fixation) were excluded. The x-rays (RUST criteria) and clinical photograph (S & S grading) were scored by two independent and blinded observers each and repeated after 1 month. Results: The overall intra-observer reliability was from 0.773 to 0.825 and inter-observer reliability from 0.635 to 0.757 for RUST scoring which was from 0.687 to 0.785 and from 0.301 to 0.650 respectively for S & S scoring. The sensitivity and specificity of S & S in predicting fracture healing were up to 82.22% and 63.64% respectively. Conclusion:The S & S test is reliable to predict the healing of lower limb fracture fixed with an intramedullary nail. The test is more useful to determine healed fractures than to determine non-healed ones.

Predictors of nonunion for transverse femoral shaft fractures treated with intramedullary nailing: a SIGN database study

“…24 Functional healing has been assessed using the S&S test, the patient's ability to perform an unassisted active knee range-of-motion squat, which we have shown to indicate earlier healing compared with radiographic evaluation, but its utility as a measure of healing is controversial. 17,20,25,26 Of the 84 patients in our cohort who had an S&S test, 83.3% of them were considered functionally healed which is similar to Scuito et al 17 who found 80.2% of their 89 patient cohort with femoral fractures were able to pass the S&S test at 24 weeks. Our findings comparing S&S with radiographic healing showed a significant correlation between the 2 tests which may add validity to the S&S examination.…”

Solid locked intramedullary nailing for expeditious return of bone-setting-induced abnormal fracture union victims to work in South-western Nigeria

“…Test for painless WB has remained one of the mainstays of determining fracture union in the clinical setting notwithstanding many advances in fracture union assessment 30 . However, in addition to physician-based clinical and radiological methods, evaluations of fracture healing should also incorporate a patient-centered approach which includes patients’ goals and expectations from the healing process as it relates to their physical and mental functioning 21 , 31 . Fascinatingly, we observed that the SIGN nail being a solid locked rod, allows early WB and return to pre-injury daily activities even when the fracture has not radiographically healed.…”

“…The fact that the S&S test is based on squatting makes it locally relevant—for social, cultural, religious or occupational reasons. Since it can assess the mobility and stability of joints, especially hip and knee, the quality of squatting is said to be a proxy reflection of the functional outcome after fixation of lower limb fracture, particularly in LMICs where other assessment modalities are either expensive or unavailable 31 , 33 .…”