Circumferential Adipofascial Graft for Prevention of Recurrence of Posttraumatic Radioulnar Synostosis.

Radioulnar synostosis can cause substantial loss of function, and surgical treatment can be challenging. Recurrence of the contracture related to scar or reformation of the synostosis is problematic. Several techniques have been described for prevention of recurrence. We present a technique utilizing a free wrap around adipofascial graft for interposition and circumferential coverage of the ulna after resection of the heterotopic bone. We believe this technique has the advantages of technical simplicity, secure interposition, and reliable outcomes.

The use of indomethacin in the prevention of postoperative radioulnar synostosis after distal biceps repair.

BACKGROUND: This study evaluated the incidence of symptomatic radioulnar synostosis/heterotopic ossification after distal biceps tendon repair in patients receiving indomethacin prophylaxis. We hypothesized that indomethacin use postoperatively would decrease the occurrence of symptomatic synostosis. METHODS: A single-center retrospective record review identified 124 patients undergoing distal biceps repair between 2011 and 2014. Patients were analyzed for administration of indomethacin, contraindications to administration, age, time to surgery, fixation method, medical comorbidities, and development of symptomatic synostosis. Oral indomethacin (75 mg, once daily) was prescribed postoperatively for 10 to 42 days per each attendings' protocol. RESULTS: After analysis, 112 patients met the inclusion criteria, with 7 undergoing a 1-incision distal biceps repair and 105 undergoing a 2-incision repair. Of those, 104 received indomethacin postoperatively, with a synostosis rate of 0.96% compared with 37.50% for the untreated group (P < .001). No statistically significant difference was found between fixation methods and synostosis. One patient with synostosis was a single-incision repair, and 3 were 2-incision suture bridge repairs. Three patients with synostosis had relative contraindications to administration of indomethacin, including concomitant warfarin use, clopidogrel use, and ulcerative colitis. CONCLUSION: Indomethacin use after distal biceps repair was associated with a statistically significant reduction in the rate of symptomatic radioulnar synostosis and did not have any associated adverse effects, including gastrointestinal bleeding or rerupture, despite prolonged use of up to 6 weeks. This study represents the largest study to report the outcomes of patients undergoing distal biceps repair with concomitant synostosis prophylaxis using indomethacin.

The utilization of a suture bridge construct for tibiofibular instability during transtibial amputation without distal bridge synostosis creation.

Symptomatic distal tibiofibular instability is a known complication of trauma-related transtibial amputations. Overt proximal tibiofibular dislocations, which are easily recognized on routine radiographs, may occur concurrently with the traumatic injury or amputation. More commonly, however, the proximal tibiofibular joint remains structurally intact in the presence of distal instability due to the loss of the distal syndesmotic structures and damage to the interosseous membrane, resulting in fibular angulation and distal tibiofibular diastasis. Some authors have espoused treating this instability with the creation of a distal tibiofibular bridge synostosis (the so-called Ertl procedure or modifications there of) to prevent potentially painful discordant motion and to minimize the prominence of the residual distal fibula. Recent studies, however, have suggested an increase in complication and reoperation rates in transtibial amputations that received a bridge synostosis compared with standard transtibial amputations. Additionally, although there are several described techniques for bridge synostosis creation, most are dependent on having sufficient remaining fibula to construct the bone bridge without unnecessary shortening of the tibia; however, sufficient residual fibula is not always available after traumatic and trauma-related amputations. We propose a technique utilizing a suture bridge to restore tibiofibular stability when performing transtibial amputations in patients with proximal tibiofibular dislocations or distal diastasis, avoiding the potential need for a distal bridge synostosis.

Ultraviolet light-irradiated photocrosslinkable chitosan hydrogel to prevent bone formation in both rat skull and fibula bone defects.

In the field of orthopaedic surgery, an orthopaedic surgeon sometimes requires to suppress excessive bone formation, such as ectopic bone formation, ossifying myositis and radio-ulnar synostosis, etc. Ultraviolet (UV) light irradiation of a photocrosslinkable chitosan (Az-CH-LA) generates an insoluble hydrogel within 30 s. The purpose of this study was to evaluate the ability of the photocrosslinked chitosan hydrogel (PCH) to inhibit bone formation in an experimental model of bone defect. Rat calvarium and fibula were surgically injured and PCH was implanted into the resultant bone defects. The PCH implants significantly prevented bone formation in the bone defects during the 4 and 8 week observation periods. In the PCH-treated defects, fibrous tissues infiltrated by inflammatory cells were formed by day 7, completely filling the bone defects. In addition to these findings, expression of osteocalcin and runt-related gene 2 (RUNX2) mRNA, both markers of bone formation, was lower in the PCH-treated defects than in the controls. In contrast, collagen type 1α2 and α-smooth muscle actin (α-SMA) mRNA levels were significantly higher in the PCH-treated defects after 1 week. PCH stimulated the formation of fibrous tissue in bone defects while inhibiting bone formation. Thus, PCH might be a promising new therapeutic biomaterial for the prevention of bone formation in orthopaedic surgery.

Preventing recurrence of radioulnar synostosis with pedicled adipofascial flaps.

The surgical treatment of post-traumatic radioulnar synostosis is difficult. Recurrence after resection alone is a concern with poor long-term maintenance of forearm rotation. We report on the use of pedicled adipofascial flaps to prevent recurrence and facilitate maintenance of movement in six adult patients with radioulnar synostosis. Five involved the proximal radioulnar joint and one the distal radioulnar joint. In four the flap was based on the radial artery and in two on the posterior interosseous artery. Mean intraoperative supination was 78° and pronation was 76°. Mean follow up was 32 months. At follow-up, mean supination was 71° and pronation was 70°. No patient had radiological recurrence of synostosis. The only complication was a transient posterior interosseous nerve palsy. Pedicled adipofascial flaps are a safe addition to resection alone which may prevent recurrence and maintain the range of forearm rotation achieved at operation.

Ex vivo Noggin gene therapy inhibits bone formation in a mouse model of postoperative resynostosis.

BACKGROUND: Resynostosis following surgical correction of primary craniosynostosis necessitates further surgical intervention, thereby increasing morbidity and mortality. Bone morphogenetic proteins are known to be expressed during normal bone healing. This study tested the hypothesis that treatment of suturectomy sites with Noggin, an extracellular antagonist of bone morphogenetic proteins, would inhibit postoperative resynostosis in a mouse suturectomy model. METHODS: Healing of small interfrontal suturectomies was assessed in three groups of mice using radiographic, micro-computed tomographic, and histologic analyses. The groups were as follows: group 1, no treatment (n = 36); group 2, green fluorescent protein (GFP)-labeled cells in a collagen scaffold (n = 36); and group 3, Noggin/GFP-expressing cells in a collagen scaffold (n = 36). RESULTS: Radiographic analysis of defect area showed that Noggin-treated suturectomy sites were significantly larger than untreated sites 4 and 8 weeks postoperatively (p < 0.05). Analysis of defect volume showed that Noggin-treated defects were significantly larger than untreated defects at all time points after surgery. The GFP-treated defects demonstrated some inhibition of bone formation, but this inhibition was not significant compared with untreated controls 12 weeks after surgery. CONCLUSIONS: These findings suggest that Noggin is an effective inhibitor of bone formation within small suturectomy sites and that Noggin may be useful in avoiding postoperative resynostosis. Noggin treatment may be useful as an adjunct to traditional surgical intervention for the treatment of children with craniosynostosis.

Anti-TGF-beta2 antibody therapy inhibits postoperative resynostosis in craniosynostotic rabbits.

BACKGROUND: Postoperative resynostosis is a common clinical finding. It has been suggested that an overexpression of transforming growth factor (TGF)-beta2 may be related to craniosynostosis and may contribute to postoperative resynostosis. Interference with TGF-beta2 function with the use of neutralizing antibodies may inhibit resynostosis. The present study was designed to test this hypothesis. METHODS: New Zealand White rabbits with bilateral coronal suture synostosis were used as suturectomy controls (group 1, n = 9) or given suturectomy with nonspecific, control immunoglobulin G antibody (group 2, n = 9) or suturectomy with anti-TGF-beta2 antibody (group 3, n = 11). At 10 days of age, a 3 x 15-mm coronal suturectomy was performed. The sites in groups 2 and 3 were immediately filled with 0.1 cc of a slowly resorbing collagen gel mixed with either immunoglobulin G (100 mug per suture) or anti-TGF-beta2 (100 mug per suture). Three-dimensional computed tomography scan reconstructions of the defects were obtained at 10, 25, 42, and 84 days of age, and the sutures were harvested for histomorphometric analysis. RESULTS: Computed tomography scan data revealed that the suturectomy sites treated with anti-TGF-beta2 showed significantly (p < 0.05) greater areas through 84 days of age compared with controls. Histomorphometry also showed that suturectomy sites treated with anti-TGF-beta2 had patent suturectomy sites and more fibrous tissue in the defects compared with sites in control rabbits and had significantly (p < 0.001) less new bone area (by approximately 215 percent) in the suturectomy site. CONCLUSIONS: These data support the initial hypothesis that interference with TGF-beta2 function inhibited postoperative resynostosis in this rabbit model. They also suggest that this biologically based therapy may be a potential surgical adjunct to retard postoperative resynostosis in infants with craniosynostosis.