Transfocal Osteotomy to Treat Shear (Oblique) Non-union of Tibia.

Aseptic non-unions of tibial shaft fractures often need surgical treatment which carry significant socio-economic implications. The causes for non-union include patient co-morbidities, high energy trauma, open fractures and fracture geometry. Oblique fractures are subject to shear forces and, if not adequately neutralised, will fail to unite. Experiments have shown that callus formation is poor in oblique fractures due to local shear stresses. We report a technique of minimally invasive transfocal transverse osteotomy and compression in a hexapod circular fixator, Taylor Spatial Frame (TSF) for 12 patients treated with a shear non-union of tibia between 2010 and 2019. There are four female and eight male patients. The average age is 49 years (range from 26 to 72 years). The fracture pattern was oblique (30-45°) in all cases. Healing of the non-union occurred in 12 cases with one case needed additional treatment with bone marrow aspirate and demineralized bone matrix. The technique of creating a minimally invasive transfocal transverse osteotomy through the oblique non-union of tibia and the use of a hexapod circular fixator to compress the osteotomy is described and adds to the range of treatments available for aseptic non-union of tibia. How to cite this article: Lahoti O, Abhishetty N, Al-Mukhtar M. Transfocal Osteotomy to Treat Shear (Oblique) Non-union of Tibia. Strategies Trauma Limb Reconstr 2022;17(2):117-122.

In vivo distraction force and length measurements of growing rods: which factors influence the ability to lengthen?

STUDY DESIGN: Prospective, intraoperative force measurement in consecutive lengthening procedures in a series of growing-rod patients undergoing lengthening. OBJECTIVE: The purpose of this study was to measure the forces and amount of distraction over time in early onset scoliosis patients treated with growing rods. SUMMARY OF BACKGROUND DATA: Growing rods are one of the current techniques used in the treatment of early onset scoliosis, and the goal of the growing-rod technique is to achieve deformity correction, maintaining spinal growth at the same time. Gradual stiffening or spontaneous fusion of the spine can interfere with the ability to lengthen. In addition, diminished acquired length with serial distraction are common observations and need to be evaluated and quantified. METHODS: Distraction forces were measured prospectively during 60 consecutive lengthening procedures in 26 patients. All patients had single submuscular rod constructs with side-to-side connectors. For each measurement, output from a transducer on a dedicated pair of distraction calipers was recorded at zero load status and the force was then recorded at every 1 mm lengthening; length was obtained at each event and was recorded in millimeters. RESULTS: The force required to distract the spine doubled at the 5th lengthening procedure (mean 368 N ± 54 N), and the distraction force was significantly higher at the fifth lengthening compared with the previous lengthening (P <0.01). Mean length achieved at each distraction decreased over time such that by the fifth lengthening, consistently 8 mm or less was achieved. CONCLUSION: Distraction forces increase significantly after repeated lengthening of growing-rod constructs, and the length obtained at each procedure exhibits a decreasing trend.