One challenge in wound care is to effectively manage soft-tissue defects in the lower extremities, which usually coexist with Gustilo type IIIB open tibial fractures and full-thickness necrotizing fasciitis.¹ In an attempt to salvage these open complex leg lesions, appropriate soft-tissue reconstruction is typically required to reduce the risk of bone infection and to increase the survival of exposed vital structures, thereby preventing limb amputation.^2–4 Since the late 1980s, numerous medical centers started successfully reconstructing the majority of traumatized lower extremities using microvascular free-tissue transfers.^1,2 Thus, it is now widely accepted that open complex leg injuries require combined specialized orthopedic and plastic surgical treatment.^5–7

However, most patients who arrive at regional hospitals with open complex leg injuries do not have access to combined orthopedic and plastic surgical services.⁷ Microvascular free tissue transfer is technically demanding work and has a steep learning curve. Most orthopedic surgeons do not have extensive microsurgical training and would hesitate to manage a patient with open complex leg injuries without plastic surgery support. Inter-hospital transfer typically results in a delay in applying definitive surgical treatment and can deleteriously affect the final clinical outcome.^8–10 Therefore, the use of uncomplicated reconstructive methods, such as local muscle flap transfer by the front-line orthopedic surgeon, may be an appropriate solution. The present study evaluates the feasibility of applying local muscle flaps in managing patients who present with massive tibia bone exposure due to Gustilo type IIIB open fractures and full-thickness necrotizing fasciitis.

Methods

Between July 2002 and December 2004, 34 consecutive patients with exposed tibia bone wounds were treated with local muscle flap transfer by an orthopedic surgeon. The main etiologies in this case series were Gustilo type IIIB open tibial fractures (76.5%) and full-thickness necrotizing fasciitis (23.5%). Patients with open, complex, lower extremity injuries underwent routine debridement. Rigid internal fixation was applied to the open fractured tibia bone at the same time as debridement. Radical debridement typically resulted in full-thickness skin defects with exposed tibia bone or implants. Adjacent muscles were examined carefully during debridement. One or 2 local muscle flaps were selected, harvested, and transferred (based on their reach and size) to cover exposed tibia bone or implant. No microvascular surgical intervention was performed and no plastic surgeons participated in this study. Data was taken from discharge summaries, operation notes, patient histories, physical examinations, and follow-up comments. All patients received regular follow-up for a minimum of 12 months.

The mean/median age of the patients was 55.7/62.5 years (range 14–85 years). Twenty-six were male (76.5%) and 8 female (23.5%). Nineteen patients (55.9%) had right side lesions and 15 patients (44.1%) had left side lesions. In this case series, 26 patients underwent single local muscle flap transfer to cover exposed tibia bone and 8 underwent double flap transfer. Comparison between these groups was performed. Mean/median age in the single flap group was 56.3/62 years (range 14–85 years): 20 were male (76.9%) and 6 female (23.1%). Nine patients (34.6%) had proximal third defects, 3 (11.5%) had middle third defects, and 14 (53.8%) had distal third defects. The mean estimated defect area was 8.0 ± 4.9 cm². For the single flap group, mean/median hospital stay following flap transfer was 19.4/12.5 days (range 8–72 days). Mean/median age in the double flap group was 54.1/62.5 years (range 23–73 years). Six were male (75%) and 2 female (25%). Five patients (62.5%) had proximal-third defects, 6 (75%) had middle-third defects, and 7 (87.5%) had distal-third defects. Mean estimated defect area was 39.8 ± 22.5 cm². For the double flap groups, mean/median hospital stay following flap transfer was 22.4/19 days (range 12–43 days).

Statistical evaluations between the single and double flap transfer groups utilized the Wilcoxon rank sum test and Fisher’s exact test; P < 0.05 was considered statistically significant.

Selection of local muscle flap transfer for wound coverage. Many muscles are potentially effective for wound coverage of tibia bone exposure.^11–13 The selection principle of muscle flaps for soft-tissue coverage is shown in Figure 1. The distance between the lower end of the medial malleolus and the tibial tuberosity is measured and divided into 3 parts—proximal third, middle third, and distal third. The medial gastrocnemius muscle flap was always selected for covering the soft-tissue defects in cases of proximal third tibia bone exposure. The soleus or hemi-soleus muscle flap was usually used for reconstruction of middle third tibia bone exposure. Both flaps are reliable donors for coverage of the corresponding soft-tissue defects.

Wound closure of soft-tissue defects of the distal third tibia is challenging. Although microvascular free tissue transfer is the common solution to distal third tibia defects, several potential muscles can be used as rotational myoplasty. A precise working knowledge of the anatomy of the muscles under consideration is critical to a safe and successful transfer of a local muscle flap. There is a considerable volume of literature available on this subject, and the authors selected the potential local muscle flaps according to the numerical data reported by Hughes et al.¹¹ The average reach (the distance between the medial malleolus and the distal end of the transposed flaps) of soleus, flexor digitorum longus (FDL), peroneus brevis (PB), extensor digitorum longus and peroneus tertius (EDL + PT), and extensor hallucis longus (EHL) was about 30%, 51%, 68%, 83%, and 83.7%, respectively. For the distal 10%–15% of the lower third tibia defects, the authors will consider, explore, and transfer the extensor digitorum brevis (EDB) muscle flap for coverage when appropriate.¹² Use of the tibialis posterior or the tibialis anterior as a donor flap was precluded by functional necessity.

Results

No major clinical complications or mortality existed in this case series. The survival rate of local muscle flap transfer was 95.2% (40/42 flaps). Two flaps (both in the double flap group) were complicated with partial necrosis. Applying the Crane principle,^1,14 these partially necrotic flaps were managed using limited debridement, leaving the eschar on the wound bed. As a result of continued careful observation and meticulous care of the wound, the authors determined that granulation tissue formed under the eschar and the soft-tissue defects eventually healed without complications. There was no need to repeat the local flap transfer for these patients or to refer them to a plastic surgeon for microvascular free tissue transfer.

Table 1 presents the differences between the single flap and double flap groups. Before comparing between the groups, their similarities were analyzed. Age (P = 0.50), gender (P = 0.36), involved sides (P = 0.29), and underlying diagnosis (P = 0.20) were similar between groups. A comparison of the estimated defect area between single and double flap transfer groups indicated that the difference was statistically significant (P < 0.001). However, no significant difference existed for hospital stay after flap transfer (P = 0.10) and complication rate (P = 0.58) between groups.

Discussion

The authors propose that local muscle flap transfer for covering wounds with exposed tibia bone or implants is an efficacious surgical procedure for front-line orthopedic surgeons. Success rate in this series was 95.2% (40/42 flaps). Only two flap transfers were complicated with distal flap necrosis, both of which healed under the guidance of the Crane principle without repeat flap transfers.^1,14 This good clinical result indicates that local transplantation of muscle flaps to cover exposed tibia bone or implants should be considered during initial debridement. When appropriate, surgeons should not hesitate to utilize local muscle flap transfer. This reconstructive approach facilitates adequate debridement and provides the bulk needed to obliterate any dead space, thereby reducing the likelihood of deep infection and improving fracture treatment outcome.^2–4 This technique is less complicated than free tissue transfer and does not require microvascular anastomosis, and can therefore be utilized by orthopedic surgeons in regional hospitals without plastic surgery support.



Comparison of statistical differences between the single and double flap transfer groups indicated that the difference in estimated defect area was strongly significant. The differences between the two groups for hospital stay following flap transfer and complication rate were not significant. The mean estimated defect area was 8.0 ± 4.9 cm² and 39.8 ± 22.5 cm² for the single and double flap groups, respectively. The double flap transfer group typically had a larger defect area with exposed tibia bone than the single flap transfer group (P < 0.001). Analytical results, however, indicated that the double flap transfer group did not require a longer healing time (P = 0.10) or have a higher complication rate (P = 0.58) than the single flap transfer group. Therefore, the authors recommend using multiple local muscle flap transfers for covering massive tibia bone exposure. This technique should always be considered when appropriate donor flaps are found during debridement (Figure 2 and Figure 3).

Many analytical studies demonstrated the efficacy of combined orthopedic and plastic surgical management at a dedicated trauma centers.^5–7 Orthopedic surgeons, with plastic surgical support, can perform radical debridement of contaminated tissues and rigid stabilization of fractures without fear of vital structure exposure or biomaterial-centered infection.⁶ Following orthopedic management, plastic surgeons typically perform early soft-tissue reconstruction.^8–10 Most experienced plastic surgeons favor reconstructing these soft-tissue defects with free flap transfers even though free tissue transfer is technically demanding, costly, and time-consuming.^1,15–17 Combined treatment of soft-tissue and skeletal components by dedicated surgical teams has improved clinical outcomes and reduced defect-related morbidity. Therefore, it is now widely accepted that open complex lower extremity injuries require combined specialized orthopedic and plastic surgical treatment.^5–7

Most patients with open complex leg injuries present at regional hospitals that do not have resident plastic surgeons.⁷ Most orthopedic surgeons do not have extensive microsurgical training and cannot perform microvascular free tissue transfers, which is technically demanding and has a steep learning curve. In the absence of plastic surgery support, orthopedic surgeons are typically reluctant to aggressively excise devitalized tissue and internally fixate fractured bones.⁶ Inadequate initial debridement and skeletal fixation combined with the delay associated with patient transfer for soft-tissue reconstruction inevitably renders definitive treatment difficult and contributes to an unsatisfactory clinical outcome. Revision of skeletal fixation is frequently necessary due to improper implant selection, insufficient skeletal stability, and refractory deep infection. Delayed soft-tissue reconstruction is also complicated due to tissue edema, perivascular fibrosis, and increased risk of venous thrombosis, which further reduces flap survival.^7,18–20 These problems might be solved if the front-line orthopedic surgeon considers performing local muscle flap transfers during initial debridement. All that is required for this uncomplicated technique is knowledge of the muscle anatomy under consideration.

Conclusion

Adequate initial debridement and timing of soft-tissue coverage are critical factors in determining the surgical outcome for these injuries.^5,7–10 Primary referral to a specialist center for simultaneous management by an orthopedic and a plastic surgeon is good protocol;^6,7 however, many hospitals do not follow this clinical guideline.⁷ This study demonstrates that an alternative of treatment exists that permits simultaneous radical debridement, rigid skeletal fixation, and soft-tissue coverage, without the need for microvascular anastomosis. Local muscle flap transfer is far less complicated than microvascular free tissue transfer and can be performed by orthopedic surgeons at regional hospitals without plastic surgery support.^21,22 When necessary, local transplantation of multiple muscle flaps to cover massive tibia bone exposure should be considered.