Closed bone graft epiphysiodesis for avascular necrosis of the capital femoral epiphysis.

BACKGROUND: Avascular necrosis (AVN) of the capital femoral epiphysis (CFE) after an unstable slipped capital femoral epiphysis (SCFE), femoral neck fracture or traumatic hip dislocation can result in severe morbidity. Treatment options for immature patients with AVN are limited, including a closed bone graft epiphysiodesis (CBGE). However, it is unclear whether this procedure prevents AVN progression. QUESTIONS/PURPOSES: We investigated whether early MRI screening and CBGE prevented the development of advanced AVN changes in the CFE and the rates of complications with this approach. METHODS: We prospectively followed all 13 patients (seven boys, six girls) with unstable SCFEs (six patients), femoral neck fractures (five patients), and traumatic hip dislocations (two patients) and evidence of early AVN treated between 1984 and 2012. Mean age at initial injury was 12 years (range, 10-16 years). Nine of the 13 patients had followup of at least 2 years or until conversion to THA (mean, 4.5 years; range, 0.8-8.5 years), including two with unstable SCFEs, the five with femoral neck fractures, and the two with traumatic hip dislocations. All patients had technetium scans and/or MRI within 1 to 2 months of their initial injury (before CBGE) and all had evidence of early (Ficat 0) AVN. Patients were followed clinically and radiographically for AVN progression. RESULTS: Six of the nine hips did not develop typical clinical or radiographic evidence of AVN. These six patients have been followed 6.3 years (range, 4.3-9.1 years) from initial injury and 5.9 years (range, 3.8-8.5 years) from CBGE. The remaining three patients were diagnosed with AVN at periods ranging from 3 to 6 months after CBGE. CONCLUSIONS: Early recognition and treatment of AVN with a CBGE may alter the natural history of this complication. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Biomechanical evaluation of 3-part proximal humerus fractures: a cadaveric study.

Proximal humerus fractures occur frequently, and treatment remains controversial. This study compares stiffness in axial loading for 3 methods of fixation (locking compression plate, standard (nonlocking) proximal humerus plate, and blade plate) in a 3-part proximal humerus fracture model. Twelve paired proximal humeri were obtained from embalmed human cadavers and separated into 3 groups. Osteotomies of the surgical neck and greater tuberosity were created to simulate a 3-part proximal humerus fracture. After fixation, constructs were axially loaded in 20 degrees of abduction for 200 cycles in an Instron materials testing machine (Norwood, Massachusetts). The blade plate (mean, 146.87+/-28.9 N/mm) demonstrated 29% more mean stiffness than the standard plate (mean, 113.0+/-22.3 N/mm; P=.19). The locking compression plate (mean, 130.71+/-39.2 N/mm) exhibited 15% greater stiffness compared to the standard plate in our 3-part model (P=.58). The blade plate demonstrated 12% greater stiffness than the locking compression plate (P=.64). There was no significant difference in mean stiffness between the fixed-angle devices and the standard plate. Future in vitro and clinical studies of plate devices for proximal humerus fractures would be worthwhile to determine the benefits and limitations of various implants for specific types of fractures, including clinical performance and cost of care.