Comparison of Outcomes by Reconstructive Strategy in Patients with Prostheses for Proximal Femoral Focal Deficiency

Background:The present study compares prosthetic treatment options for proximal femoral focal deficiency in terms of gait analysis, oxygen consumption, and patient-reported outcomes.Methods:Twenty-three patients who had been managed with a prosthesis for unilateral proximal femoral focal deficiency underwent gait analysis; this group included 7 patients who had received an equinus prosthesis, 6 who had received a rotationplasty prosthesis, and 10 who had undergone Syme amputation and had received an above-the-knee prosthesis. Cadence parameters, kinematic and kinetic data, and oxygen consumption were measured, and the Gait Deviation Index (GDI) was calculated. Medical records and radiographs were reviewed. The Pediatric Outcomes Data Collection Instrument (PODCI) was completed by the child's parent.Results:Patients underwent gait analysis at a mean age of 11.6 years (range, 4 to 19 years). Proximal femoral focal deficiency classification was not predictive of the chosen treatment. Patients in the rotationplasty group had undergone more procedures than those in the Syme amputation and equinus groups (mean, 3.3, 1.8, and 0.7 procedures, respectively) (p = 0.001). Oxygen cost did not differ between groups; however, all required greater energy expenditure than normal (170%, 144%, and 159%, in the equinus, rotationplasty, and Syme amputation groups, respectively) (p = 0.427). Likewise, hip power, abductor impulse, and GDI did not differ, but all groups had GDI scores >3 standard deviations below normative values. Patients in the equinus group walked faster (97% of normal for age) than those in the rotationplasty (84%) and Syme amputation groups (83%) (p = 0.018), whereas those in the Syme amputation group had superior knee range of motion (55° from the prosthetic knee) than those in the equinus (20°) and rotationplasty groups (15° generated from the ankle) (p = 0.003). There were no differences in terms of the PODCI subscales for pain, sport/physical function, happiness, or global function. Transfer/basic mobility improved with age (r = 0.516, p = 0.017), but no other associations were found between gait variables and PODCI scores.Conclusions:Rotationplasty provided no patient-reported benefit and no functional benefit in terms of gait parameters or oxygen consumption, despite requiring more surgical procedures compared with other prosthetic options. Patients with an equinus prosthesis walked the fastest, whereas treatment with a Syme amputation and prosthetic knee yielded equivalent gait parameters and oxygen consumption as compared with those for patients using an equinus prosthesis. These findings contradict those of previous reports that rotationplasty provides superior function over other proximal femoral focal deficiency prosthetic treatment options.Level of Evidence:Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.