Article

Ectopic Bone Formation after Temporal Muscle Transposition for Facial Paralysis

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Abstract

This report describes the case of a patient with congenital bilateral facial paralysis in whom ectopic bone formation developed following temporal muscle transposition. Ectopic bone formation was first noticed 4 years after surgery. Whether the ossification is a result of the transfer of periosteum or the osteogenic capacity of muscular tissue is still unknown.

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... Patients usually present with pain and swelling and, if in close proximity to a joint, a reduced range of motion. 1 Ectopic bone formation following temporalis muscle transposition for congenital facial palsy has been reported only twice before in children. 2,3 An eleven-year-old female with right sided congenital facial nerve palsy underwent temporalis transfer to the upper and lower eyelids and modiolus. A composite myofascial sling was raised as a conjoined unit to create a 12 cm sling. ...
... Ectopic bone formation can follow soft-tissue trauma or surgery however; atraumatic HO has also been reported. 1,2 Other causes include genetic, burns and also neurogenic injury. Post-surgical HO has been found to occur most frequently following total hip arthroplasty and spinal surgery. 1 It is widely recognised that osteophyte formation may occur in non skeletal tissue. ...
... Post-surgical HO has been found to occur most frequently following total hip arthroplasty and spinal surgery. 1 It is widely recognised that osteophyte formation may occur in non skeletal tissue. 2,3 Although the precise pathogenesis is still unclear, several theories implicating trauma and the role of various local and humoral factors, osteogenic precursor cells and bone morphogenetic proteins (BMP) have been suggested. 1e3 Symptoms depend on the size and anatomical site. ...
... Heterotopic or Ectopic ossification is the formation of lamellar bone in soft tissues or other tissues remote from the usual location of bone. Formation of heterotopic ossification (HO) following tissue transfer for reconstruction has been reported anecdotally [1][2][3][4][5]. One of these studies also reported that the severity of heterotopic ossification is significantly higher in muscle flaps around the joints [5]. ...
Article
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We report a case of development of a movement restricting heterotopic ossification after a free functioning gracilis muscle transfer performed for elbow flexion in a patient with pan brachial plexus palsy. We also present the management of the case including the repair of the brachial artery which was thinned out by the lesion. To the best of our knowledge, this is the first case in literature which reports heterotopic ossification after a free functioning muscle transfer.
... Even today tissue mineralization during bone formation is not fully understood (36) but evidence is increasing that mineralization per se is not a challenge [as illustrated by ectopic bone formation (37)(38)(39), fibrodysplasia ossificans progressiva, or uncontrolled bone formation after limb amputation (40)]. For healthy functional bone to form and to harbor the best quality to withstand strains and stresses of daily life, a controlled, structure-optimizing, and directed bone formation is key to success. ...
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Bone is a unique organ able to regenerate itself after injuries. This regeneration requires the local interplay between different biological systems such as inflammation and matrix formation. Structural reconstitution is initiated by an inflammatory response orchestrated by the host immune system. However, the individual role of T cells and B cells in regeneration and their relationship to bone tissue reconstitution remain unknown. Comparing bone and fracture healing in animals with and without mature T and B cells revealed the essential role of these immune cells in determining the tissue mineralization and thus the bone quality. Bone without mature T and B cells is stiffer when compared to wild-type bone thus lacking the elasticity that helps to absorb forces, thus preventing fractures. In-depth analysis showed dysregulations in collagen deposition and osteoblast distribution upon lack of mature T and B cells. These changes in matrix deposition have been correlated with T cells rather than B cells within this study. This work presents, for the first time, a direct link between immune cells and matrix formation during bone healing after fracture. It illustrates specifically the role of T cells in the collagen organization process and the lack thereof in the absence of T cells.
... 31 However, the formation of heterotopic ossification following tissue transfer has been a very rarely reported complication limited, to our knowledge, to individual case reports. 33,34 Both of these reports involved the transfer of the temporalis muscle for reconstruction of a congenital facial paralysis with subsequent heterotopic ossification formation. It was proposed that this occurred because of a small amount of periosteum having been transferred with the original surgery. ...
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Background: Although mechanisms underlying heterotopic ossification remain unknown, certain risk factors can influence heterotopic bone formation. The purpose of this study was to determine whether flaps used in periarticular reconstruction had any effect on heterotopic ossification formation. Methods: A retrospective review of periarticular injuries requiring flap coverage from 2003 through 2014 was performed. Flap types, Injury Severity Scores, functional outcomes, and complications were reviewed. Radiology findings were assessed to determine heterotopic ossification rates and grades. Results: Three hundred eighty-nine flaps were performed for traumatic extremity coverage over the 13-year study period. Sixty-nine of these flaps were used for periarticular coverage. The rate of periarticular heterotopic ossification was 47 percent for fasciocutaneous versus 54 percent for muscle-based flap coverage (p = 0.88). There were no significant differences in Injury Severity Score (p = 0.44) or overall heterotopic ossification formation (p = 0.97) between groups; however, the grade of heterotopic ossification within muscle-based flap cohort was significantly higher (1.70 for muscle versus 1.06 for the fasciocutaneous cohort; p = 0.002). Conclusions: Combat-related trauma is associated with high rates of heterotopic ossification, with an overall formation rate exceeding 85 percent for our patients requiring periarticular flap coverage. Although no difference in the rate of heterotopic ossification formation was found between fasciocutaneous and muscle flap coverages, a significantly increased severity of heterotopic ossification was seen in periarticular muscle-based flaps. These findings suggest that flap composition might not affect the rate of heterotopic ossification formation but may have an effect on ectopic bone formation severity.
... Free or regional muscle transfers have been used to restore oral function in complete orbicularis oris paralysis if open-mouth deformity is due to total facial nerve paralysis. 4,5 The case of twin brothers with Möbius syndrome who had open-mouth deformity is presented. Fortunately, their facial paralyses were incomplete. ...
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Treatment of open-mouth deformity and augmentation of the upper lip were performed using a combination of double-row V-Y mucosal advancement flaps and a V-Y skin advancement flap in 2 cases with Möbius syndrome. The mucosal V-Y advancement flaps were consisted for 2 rows of flaps. The first row was placed near the labial sulcus, including 3 V-Y advancement flaps. These flaps equally provided 3 directional augmentation for each segment of the upper lip. Second row V-Y mucosal advancement flap was used for the augmentation of the vermilion tubercle. In our cases, V-Y advancement flaps were used as subcutaneous based flaps unlike other distally based V-Y flap techniques for the upper lip. Postoperative complications such as scar formation, sensation problems, severe pain, and edema were decreased because of subcutaneous pedicled V-Y flaps. In addition, the relationship between mucosa and orbicularis oris muscle, which is responsible for the fine balance of the vermilion, was maintained with subcutaneous-based flaps. The skin V-Y advancement flap was used both to lengthen the upper lip and to create philtral columns on the upper lip.
... 153,154 Ectopic bone formation has been described as a rare complication of temporalis muscle transfer years after surgery. 26 Free muscle grafts with microneurovascular anastomosis are fast becoming a standardized procedure in the rehabilitation of long-standing facial palsies. 101,236 Such cross-face nerve grafts-namely, gracilis muscle transplants-use innervation from the contralateral healthy side to allow dynamic movements of the affected side. ...
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  • Nicolai
  • Urist
  • Huggins