Michael Pearse

Management of severe open tibial fractures: THE NEED FOR COMBINED ORTHOPAEDIC AND PLASTIC SURGICAL TREATMENT IN SPECIALIST CENTRES

Although it is widely accepted that grade IIIB open tibial fractures require combined specialised orthopaedic and plastic surgery, the majority of patients in the UK initially present to local hospitals without access to specialised trauma facilities. The aim of this study was to compare the outcome of patients presenting directly to a specialist centre (primary group) with that of patients initially managed at local centres (tertiary group). We reviewed 73 consecutive grade IIIB open tibial shaft fractures with a mean follow-up of 14 months (8 to 48). There were 26 fractures in the primary and 47 in the tertiary group. The initial skeletal fixation required revision in 22 (47%) of the tertiary patients. Although there was no statistically-significant relationship between flap timing and flap failure, all the failures (6 of 63; 9.5%) occurred in the tertiary group. The overall mean time to union of 28 weeks was not influenced by the type of skeletal fixation. Deep infection occurred in 8.5% of patients, but there were no persistently infected fractures. The infection rate was not increased in those patients debrided more than six hours after injury. The limb salvage rate was 93%. The mean limb functional score was 74% of that of the normal limb. At review, 67% of patients had returned to employment, with a further 10% considering a return after rehabilitation. The times to union, infection rates and Enneking limb reconstruction scores were not statistically different between the primary and tertiary groups. The increased complications and revision surgery encountered in the tertiary group suggest that severe open tibial fractures should be referred directly to specialist centres for simultaneous combined management by orthopaedic and plastic surgeons.

Apoptosis – a significant cause of bone cell death in osteonecrosis of the femoral head

Osteonecrosis of the femoral head usually affects young individuals and is responsible for up to 12% of total hip arthroplasties. The underlying pathophysiology of the death of the bone cells remains uncertain. We have investigated nitric oxide mediated apoptosis as a potential mechanism and found that steroid- and alcohol-induced osteonecrosis is accompanied by widespread apoptosis of osteoblasts and osteocytes. Certain drugs or their metabolites may have a direct cytotoxic effect on cancellous bone of the femoral head leading to apoptosis rather than purely necrosis.

Comparison of the Healing of Open Tibial Fractures Covered with Either Muscle or Fasciocutaneous Tissue in a Murine Model

The objective of this study was to compare the effects of soft tissue coverage by either muscle or fasciocutaneous tissue on the healing of open tibial fractures in a murine model. An open tibial fracture, stripped of periosteum with intramedullary fixation, was created in mice. Experimental groups were devised to allow exclusive comparison of either muscle alone or skin plus fascia in direct contact with healing bone. To exclusively assess the relative efficacy of muscle and fasciocutaneous tissue to promote healing of a fracture stripped of periosteum, a piece of sterile inert material (polytetrafluoroethylene) was positioned anteriorly, excluding skin and fascia (muscle group) or posteriorly, excluding muscle (fasciocutaneous group). Skeletal repair was assessed histologically and quantified by histomorphometry; quantitative peripheral computed tomography (pQCT) and mechanical testing using a four‐point bending technique. This standardized, reproducible model allowed characterization of the morphology of open fracture healing. At 28 days postfracture, there was faster healing in the experimental muscle coverage group compared to skin and fascia alone. Furthermore, there was almost 50% more cortical bone content and a threefold stronger union beneath muscle compared to fasciocutaneous tissue (p < 0.05 by one‐way ANOVA). Exclusive comparison of muscle and fasciocutaneous tissue in our novel murine model demonstrates that muscle is superior for the coverage of open tibial fractures for both the rate and quality of fracture healing.

The extent of osteocyte death in the proximal femur of patients with osteonecrosis of the femoral head

Our aim was to assess the local extent of osteocyte death in the proximal femur of 16 patients with osteonecrosis of the femoral head. We performed histological examination of the femoral heads and cancellous bone biopsies from four regions of the proximal femur in patients undergoing total hip arthroplasty. A control group consisted of 19 patients with osteoarthritis. All histological specimens were examined in a blinded fashion. Extensive osteonecrosis was shown in the proximal femur up to 4 cm below the lesser trochanter in the group with osteonecrosis. There was an overall statistically significant difference in the extent of osteocyte death distal to the femoral head between the two groups (p < 0.001). We discuss the implications of these findings as possible contributing factors in regard to the early failure of total hip arthroplasty reported in patients with osteonecrosis of the femoral head.

Improving lower limb salvage following fractures with vascular injury: a systematic review and new management algorithm.

BACKGROUND Lower limb fractures with vascular injuries are associated with a high rate of secondary amputation. Reducing ischaemic time is vital for limb salvage. However, the optimal sequence of surgical management remains unclear. We aimed to review the literature to establish an evidence-based management algorithm. METHODS All identifiable English language or translated literature related to the surgical sequence of lower limb fractures with vascular injuries was reviewed. RESULTS A total of 101 cases described in 10 publications (median age: 31; range: 2.5-76) were suitable for analysis. The mean MESS was 4.2. The limb-salvage rate with an ischaemic time of less than 6h was 87%, falling to 61% when ischaemic time exceeded 6h. A preoperative angiography caused a significant delay. The rate of re-vascularisation within 6h improved from 46% (33 of 71) to 90% (27 of 30) with the use of a shunt (p=0.04), with a mean ischaemic time of 3.8h (+/-1.7h, 1 standard deviation (SD)) versus 7.6h (+/-3.8h, 1SD) in those re-vascularised using grafts (p<0.001). The amputation rate of 27% was reduced to 13% by using shunts. CONCLUSION Early recognition of vascular injury is vital. Formal angiograms are unnecessary and cause crucial delays. A vascular shunt can significantly reduce ischaemic time, enabling unhurried assessment of the feasibility of limb salvage, debridement of demonstrably non-viable tissue and safe skeletal fixation prior to definitive vascular and soft-tissue repair.

Comparison of the vascularity of fasciocutaneous tissue and muscle for coverage of open tibial fractures.

Background: Early coverage with vascularized soft-tissue flaps has dramatically improved the outcome in open tibial fractures. However, the ideal tissue for covering open fractures remains controversial. Several clinical studies suggest that muscle is superior to fasciocutaneous tissue; this is attributed to the presumed higher vascularity of muscle, although experimental evidence is inconclusive. The authors’ previously described novel murine fracture model, which allows exclusive comparison of both tissues, demonstrated enhanced healing beneath muscle. The present study was undertaken to compare the vascularity of muscle and fasciocutaneous tissues over the course of fracture healing. Methods: Two experimental groups comprised mice with tibial fractures in contact with either muscle or fasciocutaneous tissues exclusively. Controls included a nontrauma group and those where soft tissues and periosteum were dissected but the tibia was not fractured. Animals were harvested between 3 and 28 days after fracture (n = 170 in total). The vascular density of the soft tissues was assessed using immunohistochemical techniques. Results: Fasciocutaneous tissue was found to have a higher vascular density compared with muscle in contact with the fracture site at all time points (p < 0.0001, two-way analysis of variance), despite accelerated healing of fractures covered by muscle. Conclusions: The authors’ data show that the more advanced healing of fractures covered by muscle compared with fasciocutaneous tissue is not related to the vascularity of the tissues, as the latter had a higher vascular density at all time points. Therefore, provided that a flap has sufficient vascularity to effectively reconstitute the soft-tissue envelope, other factors may be important in specifically promoting fracture healing.

Management of Complex Tibial Plateau Fractures with the Ilizarov External Fixator

Summary Disillusionment with the results of classical open techniques in the management of complex tibial plateau fractures has led to a move toward methods of indirect reduction and subsequent stabilization with external fixation. Stabilization of these complex articular injuries with the Ilizarov method, in combination with indirect reduction maneuvers such as ligamentotaxis, offers many advantages over conventional open reduction and internal fixation with plates. Smooth olive wires stabilize the joint fracture in the sagittal plane, and percutaneous cannulated screws can be added, when indicated, for fracture lines in the coronal plane. A three- or four-ring circular frame construct ensures adequate fixation of the metadiaphyseal junction, which is usually very unstable. Experience with this method has demonstrated that it provides sufficient stability to allow early joint motion while preserving the soft tissue envelope, with a low rate of complications secondary to surgical fixation.

management of Soft-tissue Problems in Leg Trauma in Conjunction with Application of the Ilizarov Fixator Assembly

Forty-five patients presenting with high-energy open grade III tibial diaphyseal fractures were treated with the Ilizarov technique. Of these patients, 28 required plastic surgical intervention for achieving wound closure. Most of the injuries were complicated by initial neglect and inadequate prima

The ortho-plastic management of Gustilo grade IIIB fractures of the tibia in children: A systematic review of the literature

BACKGROUND The challenges of managing Gustilo IIIB tibial fractures in children are unique. A multi-disciplinary, evidence based approach is needed. We aimed to evaluate the evidence for the ortho-plastic management of Gustilo grade IIIB open tibial shaft fractures in children based on a review of all published data in order to rationalise the orthopaedic and plastic surgical approach to these complex injuries. METHOD A systematic review of the literature was performed. Gustilo grade IIIB tibial shaft fractures in pre-adolescent and adolescent children were identified and evaluated with regard to both the skeletal and soft tissue management, and the outcome. RESULTS Of 54 children with grade IIIB tibial fractures, a mean union time of 31 weeks included 33 weeks for 42 adolescents and 23 weeks for 12 pre-adolescents. Faster union time in pre-adolescents tended towards significance. Delayed union occurred in 22%, nonunion in 13%, mostly in adolescents. Two of 45 covered by vascularised flaps and 3 of 9 treated without flaps developed deep infection (p=0.028). There was no correlation between method of skeletal fixation and union time. CONCLUSION Gustilo IIIB tibial shaft fractures in pre-adolescents tended towards faster healing with fewer complications, irrespective of the method of skeletal fixation. In adolescents, healing times were similar to adults. Soft tissue closure without flaps was associated with deep infection in one-third of patients, requiring debridement and flap cover. Adequate debridement and flap cover is suggested in all cases, irrespective of age.

The microbiological basis for a revised antibiotic regimen in high-energy tibial fractures: preventing deep infections by nosocomial organisms.

BACKGROUND Deep surgical site infections (SSIs) complicate Gustilo IIIB tibial fractures in 8-13% of cases. Antibiotic prophylaxis typically covers environmental contaminants. However, nosocomial organisms are usually implicated in deep infection. We used the microbiological profile of infected Gustilo IIIB tibial fractures to define a new, dynamic prophylactic regimen which recognises the need for prophylaxis against nosocomial organisms at the time of definitive closure. METHODS The microbiological profiles of Gustilo IIIB tibial fractures presenting over a 2-year period from January 2006 to December 2007 were reviewed. The environmental contaminants were compared with the organisms isolated from deep SSIs and correlated with the prophylactic antibiotic regimen used. RESULTS Fifty-two patients were included. Nine developed a deep tissue infection. The pathogens implicated included resistant Enterococci, Pseudomonas, Enterobacter and MRSA. Standard antibiotic prophylaxis provided cover for these combinations in only one of nine cases. This would have improved to eight of nine cases with the use of teicoplanin and gentamicin, given as a one-time dose during definitive soft-tissue closure. Specimens taken from wound debridement were neither sensitive nor specific for the subsequent development of deep infection and did not predict the organisms responsible. CONCLUSIONS Following high-energy open fracture, a single prophylactic antibiotic regimen directed against environmental wound contaminants does not provide cover for the organisms responsible for deepest SSIs and may have depopulated the niche, promoting nosocomial contamination prior to definitive closure. We advocate a dynamic prophylactic strategy, tailoring a second wave of prophylaxis against nosocomial organisms at the time of definitive wound closure, and at the same time avoiding the potential complications of prolonged antibiotic use.