REHABILITATION OF CHILDREN WITH LESIONS OF THE PROXIMAL HUMERAL METAEPIPHYSIS USING TRANSOSSEOUS DISTRACTION OSTEOSYNTHESIS TECHNIQUES

We present an analysis of the treatment of 39 children with a shortening of the humerus aft er sustained osteomyelitis. Variants of lesions of the proximal humerus metaepiphysis are highlighted, and the diff erentiated approach to therapeutic measures depending on the identifi ed changes resulted in a positive outcome.


Introduction
Humeral growth is ensured by the proximal metaepiphyseal growth plate in 80% of cases. A lesion observed aft er previous hematogenous osteomyelitis, in which there are various degrees of hypofunction as well as segmental or total destruction, not only induces signifi cant shortening of the aff ected segment and formation of a cosmetic defect but also supports the development of metaepiphyseal deformations and shoulder joint dysfunction [1][2][3][4][5][6]. However, patients seldom seek treatment even with signifi cant degrees of shoulder shortening. Th is fact can be explained by the signifi cant adaptability of the upper limb, which satisfi es functional needs of children during a long interval.
Th ere have been few reports based on suffi cient clinical materials and refl ecting treatment effi cacy in patients with sequelae of hematogenous osteomyelitis of the proximal humeral metaepiphysis [1,2]. In the non-Russian literature, data on humeral lengthening are presented but only as single observations in which approaches of shoulder shortening aft er a previous infl ammatory process are described [3][4][5][6][7][8][9][10][11][12]. However, the problems of diff erential approaches to treatment of children with this pathology, with consideration for the types of shoulder lesion, have been insuffi ciently reported, thus prompting this study.

Materials and methods
We treated 39 children (20 boys and 19 girls, 7-17 years old) with a lesion of the proximal humeral metaepiphysis and shoulder shortening at "NIDOI by G.I. Turner" from 2004 to 2014. Of the children, 19 (48.7%), 18 (46.2%), and 2 (5.1%) had right, left , and bilateral humeral lesions, respectively. All children seek treatment at shoulder shortening from 6 to 11 cm. Th e defi cit of initial length of the aff ected segment was from 21.4% to 56.5% (mean 38.5%). A complex physical examination, including clinical, roentgenological, and physiological (electromyography and rheovasography) diagnostic techniques, was performed to evaluate the anatomical and functional condition of the upper limb.

Results and discussion
Patients with a lesion of the proximal humeral metaepiphysis were comprehensively examined to defi ne the symptoms of shoulder joint lesions occurring aft er previous hematogenous osteomyelitis. Th ese symptoms included shoulder shortening associated with cicatricial changes of shoulder soft tissues and hypotrophy of shoulder and forearm soft tissues; shoulder joint dysfunction with predominant restriction of shoulder retraction; abnormality of the capitellum with dystrophic cartilaginous and osseous tissues manifesting at diff erent rates; predominant absence of humeral diaphyseal abnormalities; and segmental or total hypofunction or destruction of the proximal humeral metaepiphyseal growth plate associated with moderately decreased blood fl ow level and functional status of muscles of the aff ected limb segment.
Th e reconstruction of shoulder length and improvement of shoulder joint function are reported based on rehabilitation actions in children with a lesion of the proximal humeral metaepiphysis. Th e surgical indication was shoulder shortening of 6 cm or more as well as restriction of shoulder retraction caused by a varus deformity of the proximal humeral metaepiphysis at an angle less than 90°. Shoulder shortening was diagnosed when children began to compensate for the defi cit in length by means of distortion of posture in the frontal plane and shoulder retraction of less than 90°, which signifi cantly damaged functionality of the aff ected upper limb.
Two patient groups were defi ned for which the therapeutic approach depended on initial anatomic and functional status of the aff ected upper limb segment. Group 1 consisted of 23 patients (59%) who had all symptoms of a shoulder joint lesion associated with moderate restriction in function (Fig. 1). Group 2 included 16 patients (31%) with frank restriction of shoulder retraction associated with its shortening. Th e aforementioned dysfunctions occurred at a different manifestation rate of varus deformation of the proximal metaepiphysis of the aff ected bone (Fig. 2).
Th e pin/wire or monolateral rod external fi xators were applied on shoulders of patients in group 1 for the purpose of length reconstruction of the aff ected upper limb segment. For fi xation, two threaded rods were inserted into the proximal and distal humeral metaphysis from the outer surface, which were fi xed in two semi-ring supports of the Ilizarov apparatus at rod arrangement or three wires were led via the distal third of the humerus at pin/wire arrangement of the apparatus. Th e osteotomy was performed via an external approach in the upper third of the shoulder. Th e shoulder was lengthened by 0.25 mm four times/day beginning from 6 days post-surgery up to achievement of the intended result.
Th e arrangement of the distraction apparatus for group 2 patients was no diff erent from that in group 1, except for modification of insertion of two proximal threaded rods. Th ey were inserted in the humerus while taking into account the deformation angle of the proximal metaphysis. Th e apparatus was stabilized aft er osteotomy and correction of humeral deformation. The retraction amplitude of the surgically operated shoulder was increased by the value of deformation correction. The shoulder length was adjusted by 0.25 mm four times/day beginning from 6 days post-surgery until achievement of the intended result. In two patients with bilateral shoulder shortening, the deformation was corrected by subsequent leveling of lengths of the upper limb proximal segments by means of lengthening one segment by not more than 2 cm.
We did not perform bilocal osteotomy with deformation correction of the upper third of the humerus and lengthening of the midshaft , as has been reported by some authors [2,10], because of the increasing risk of surgical injury and risk of a lesion o the peripheral nerve trunks.
On examination, there was no signifi cant diff erence in the duration and quality of the distraction graft between groups 1 and 2. Th e graft formation duration did not statistically diff er from the average duration but depended on the value of shoulder lengthening in advanced stages. The shoulder lengthening was 7-12 cm at an average duration of shoulder fi xation in the apparatus of 11.2 days/1 cm of lengthening in group 1. Th e average duration of shoulder fi xation in the apparatus was 16.4 days/cm at a shoulder lengthening of 6-10 cm in group 2.
In contrast to other reports [1,3,8,9], we did not observe any sequelae associated with disorders of shoulder joint stability or formation of shoulder deformities on the side of the lesion resulting from shoulder lengthening. We did note neuropathies of peripheral nerves in four (10.3%) children, which stopped after conservative therapy. In one case, breakage of the proximal threaded rods did not require additional surgery, and parts of the threaded rod were extracted when the rod apparatus was removed from the shoulder. The ORTHO-SUV apparatus, which is based on passive computer navigation, was used to eliminate distraction graft deformation in one case.
A total of 27 (69.2%) patients were followed long term (from 1 to 10 years). The values of lengthening and shoulder retraction amplitude that were achieved remained in all children. Th is fi nding demonstrates an optimal approach to the reconstruction of shoulder length as well as improving and saving functions of the shoulder joint aft er hematogenous osteomyelitis in children with various manifestation rates of deformation of the proximal humeral metaepiphysis.

Conclusions
Th e shoulder shortening aft er previous hematogenous osteomyelitis is accompanied by various manifestation rates of deformations of the proximal humeral metaepiphysis. Th e length reconstruction of the aff ected shoulder should be performed taking into account the manifestation rate of humeral deformations and shoulder joint function disorders. Th e optimal approaches, using techniques of transosseous distraction osteosynthesis, to resolve shoulder length reconstruction and improve shoulder joint function ensure a positive intended result during long-term observations.