Gradual ulnar lengthening in Masada type I/IIb deformity in patients with hereditary multiple osteochondromas: a retrospective study with a mean follow-up of 4.2 years

Abstract

Background Gradual ulnar lengthening is the most commonly used procedure in the treatment of Masada type I/II deformity in patients with hereditary multiple osteochondromas. However, the treatment remains controversial for the recurrence of deformity in growing children. This study aims to evaluate the clinical and radiological outcomes of ulnar gradual lengthening in our clinic. Methods We retrospectively reviewed patients who underwent ulnar lengthening by distraction osteogenesis from June 2008 to October 2017. The carrying angle (CA) and range of motion (ROM) of the forearm and elbow were clinically assessed, and the radial articular angle (RAA) and ulnar shortening (US) were radiologically assessed before lengthening, 2 months after external frame removal, and at the last follow-up. Results The current study included 15 patients (17 forearms) with a mean age of 9.4 ± 2.3 years at the index surgery. The mean follow-up period was 4.2 ± 2.4 years. There were 9 patients (10 forearms) with Masada type I deformity and 6 patients (7 forearms) with Masada type IIb deformity. The mean amount of ulnar lengthening was 4.2 ± 1.2 cm. The mean RAA improved from 37 ± 8 to 30 ± 7° initially (p = 0.005) and relapsed to 34 ± 8° at the last follow-up (p = 0.255). There was a minimal deterioration of US yet significant improvement at the last follow-up compared to pre-op (p < 0.001). At the last follow-up, the mean forearm pronation and elbow flexion increased significantly (p < 0.001 and p = 0.013, respectively), and the mean carrying angle also improved significantly (p < 0.001). No patient with type IIb deformity achieved a concentric radial head reduction. Conclusions Gradual ulnar lengthening significantly reduces cosmetic deformity and improves function in patients with Masada type I/IIb deformity. Our results supported early ulnar lengthening for patients with a tendency of dislocation of the radial head.

Reconstruction using monorail fixator for forearm osteochondroma Masada type I and IIb: A case series

“…For ulnar lengthening in all eight patients, we used a monorail fixator. This is in line with the techniques proposed by Masada et al and two other studies [4] , [6] , [19] . The use of the uniplanar system has disadvantages in maintaining the direction of the distraction.…”

“…This research sample is the same as the case series that is being presented. They concluded that tumor resection accompanied by gradual ulnar lengthening was the right measure to correct forearm deformities that have implications for the return of normal forearm function [19] .…”

Hinge positioning method of Ilizarov apparatus in correcting radial head luxation caused by multiple hereditary exostoses

“…Chomiak et al [15] reported three out of 28 MHE patients with radial head dislocation who were treated with UL, but none of the radial heads became reduced. The same failure of which dislocated radial head did not achieve concentric reduction was seen in seven forearms using ulnar osteotomy and monolateral external fixator gradual lenthening, reported by Li et al [14] Dislocated radial head in MHE can be reduced through gradual UL with Ilizarov frame with a certain intervention to the radius. [11][12][13]26] It is considered earlier that the traction force to pull down the radial head may come from either the forearm interosseous membrane or a transfixation wire through DRUJ.…”

“…External fixators seem to be the current tendency in orthopedics, which indicates an optimistic application in forearm deformities. [8,[11][12][13][14][15][16]27] The device enables gradual, progressive, and controlled reduction of the forearm, as well as the elbow joint, and avoids excessive soft tissue interruption as well as widespread scarring. Besides, our novel hinge positioning, which is based on the expectant length and angulation of the ulna, provides adequate and balanced traction through the ring fixators and averts limiting the motion of the elbow.…”

“…[7][8][9][10] However, ulnar elongation may not promise a properly reduced radiocapitellar joint, since the intensity and direction of the force, which was transduced through interosseous membrane during lengthening, remained difficulty to control. [8,[11][12][13][14][15][16] Hinges are fundamental components of Ilizarov apparatus to correct angulating and rotational deformities. To the best of our knowledge, no study has reported where exactly these hinges should be installed to angulate the ulna and reduce the radial head.…”