Results of non-union of humerus treated with retrograde humeral nail

Failure of humeral shaft fixation: construct characteristics

PURPOSE

Fixation failure following open reduction and internal fixation (ORIF) of humeral shaft fractures can be a challenging complication. We aimed to identify the modes of failure and characteristics of failed fixation constructs.

METHODS

We queried our institutional database for patients > 18 years old with fixation failure after ORIF with single plate and screw constructs of humeral shaft fractures from 2006 to 2017. Demographics, fracture characteristics, fixation construct design and mode of failure were recorded.

RESULTS

Twenty-three failures were identified. Mean age was 55.9 years (SD 19.2 years) with 15 (65%) women. Twelve patients (52%) had midshaft fractures; the remainder had distal-third shaft (8 pts, 35%) or proximal-third shaft (3 pts, 13%) fractures. Midshaft fractures were most commonly fixed through an anterolateral approach with plates and all non-locking screws (83%), while distal-third shaft fractures were fixed with a combination of locking and non-locking screws from a posterior approach. Distal-third shaft fractures failed by plate breakage (63%) or screw pullout (38%) and all midshaft failures occurred by screw pullout proximal (92%) or distal (8%) to the fracture. Resultant varus deformity occurred in 20 (87%) fractures.

CONCLUSION

Screw pullout in midshaft fractures suggests that fixation to bone was insufficient or biomechanically disadvantageous. Varus moments contribute significantly to the failure of humeral shaft fracture ORIF. Plate breakage in distal fractures suggests high concentrations of stress over a narrow working length of constructs with inadequate plate strength. Recognizing how these constructs fail can aid proper implant selection and application for humeral shaft fracture.

LEVEL OF EVIDENCE

Treatment level IV.

Aseptic humeral shaft nonunion

Aseptic humeral shaft nonunions are rare lesions, with less than 700 cases per year in France. This low frequency explains why they are difficult to manage. They can be hypertrophic or atrophic, with or without a defect. The diagnosis is made based on radiographs and/or CT scan images. Nonunion is suspected early on when a patient presents with abnormal motion at the fracture site 6 weeks after the initial injury event in the context of conservative treatment or has large residual displacement after initial treatment or an open fracture. The treatment for hypertrophic nonunion consists in applying stable, rigid fixation, most often using a large-fragment plate with 4.5 mm screws, combined with cancellous autograft. When combined with the osteoperiosteal decortication first described by Judet, it produces union in 98% of cases. Intramedullary (IM) nail fixation with an autograft is another possibility. In atrophic nonunions, resecting the ends and ensuring the soft tissues have good vitality will generally lead to fracture union. Nonunions with critical size defects (larger than 5 cm), which have a high risk of infection, are a treatment challenge that requires stable fixation and recourse to more complex treatments like the two-step induced membrane technique or vascularized fibular graft. In all cases, to avoid complex repeat revision, internal fixation with plate or IM nail must be combined with a bone graft in situ to maximize the chances of union.

Humeral shaft non-union in the elderly: Results with cortical graft plus stem cells

INTRODUCTION

Humeral shaft is a common site of fracture non-union. Biology and bone quality represent some of the problems that the orthopaedic surgeon has to face up in the elderly. The goals of treatment of humeral shaft non-union are the achievement of mechanical stability and creation of a favourable biologic environment. Bone graft and stem cells are some of the augmentation techniques available to reach these goals.

PURPOSE

Evaluation of the outcomes of humeral shaft non-union in elderly population treated with cortical allograft and stem cells.

MATERIAL AND METHODS

A cohort of 21 patients with humeral shaft non-union was reviewed. Inclusion criteria were patients aged more than 65 years, with a diagnosis of humeral shaft non-union treated with cortical allograft and stem cells. Primary endpoints were 'bone healing' and 'time-to-union'. Secondary endpoints were shoulder and elbow function and patients' quality of life with Oxford Shoulder Score (OSS), Constant score and EuroQol-5D (EQ-5D).

RESULTS

6 patients met the inclusion criteria. In 5 of them, the cortical allograft was opposite to a plate, whereas in the other one a "Sandwich" technique was chosen because of large osteolysis. 'Bone healing' occurred in all patients after a mean of 3.3 months (range 2-5). In all but two patients, the elbow range of motion was in almost normal range (15-130). The mean OSS was 35.8 (+/- 6.4), whereas the mean Constant was 53.3 (+/- 2.2). The mean EQ-5D index was 0.451 (+/- 0.21).

DISCUSSION

Bone healing occurred in all patients, with a time-to-union comparable or even better compared with other series. The use of cortical bone graft provide both stability and biological benefit, whereas stem cells improve the non-union environmental biology. Functional outcomes were lower than other series and patients' quality of life was similar to Italian elderly women.

CONCLUSION

The use cortical allograft with stem cells is a viable strategy to treat humeral shaft non-union in the elderly.