Epiphyseal distraction monitored by strain gauges. Results in seven children

Abstract

Ten epiphyses in seven children underwent fixed-rate distraction of 0.25 mm twice daily in an attempt to achieve percutaneous leg lengthening by chondrodiatasis. The forces generated across the growth plate were recorded by means of strain gauges incorporated into the distractors. All epiphyses fractured before 33 days of lengthening. An average gain of 6.75 cm was achieved. Epiphyseal distraction at the lower femur produced many complications, but at the upper tibial epiphysis planned lengthening was achieved, with excellent bone production and few complications.

Longitudinal growth rate following slow physeal distraction the proximal tibial growth plate studied in rabbits

“…Monitoring with strain gauges would greatly minimize the risk of physiolysis. Jones et al (1989) found that using fixed rate distraction, all 10 epiphyses in their study separated within 32 days. They felt that in order to avoid failure across the growth plate, the stress should be maintained at less than 0.15 MPa.…”

“…How the accelerated growth is to be achieved during distraction and whether mechanical force stimulates or inhibits proliferating activity at the growth plate is a subject of some speculation (Trueta and Amato 1960, Hert 1969, Bourret and Rodan 1976, Brighton 1978, Jones et al 1989, Alberty et al 1990, 1993, De Pablos, Jr. and Canadell 1990, Kenwright et al 1990, Elmer et al 1992, Alberty 1993). More work is required to understand fully the response of the growth plate to mechanical forces and to realize fully the merits of slow physeal distraction.…”

Assessment of Maxillary Distraction Forces in Cleft Lip and Palate Patients

“…Forces exceeding 1500 N at the time of lyses were measured by Monticelli and Spinelli (1981) in two patients. Kenwright et al (1990) recorded the force of 600 N, and Jones et al (1989) a load of 400 N. Roermund et al (1992) monitored continuously the traction forces during tibial lengthening in a patient and found that 800 N was required for complete lyses. Forriol et al, (1997) measured the force required for distraction osteogenesis of the lamb tibia.…”

Forces measured during femoral lengthening in children

“…These experiments were done to determine if fracture of the physis was a necessary part of leg lengthening. Jones et al (1989) studied the forces in 10 lengthened segments in 7 children. Lengthening of 0.5 mm per day was performed in 2 sessions of 0.25 rnm.…”

“…Similar animal studies have been performed (Kenwright and White 1989). Two papers have looked at distraction forces required to lengthen the lower limb during physeal distraction (Kenwright et al 1990 andJones et al 1989). No work has been published on forces during distraction of the femur either in humans or in animals.…”