Leg Reconstruction: Middle Third

Clinical Presentation

A 40-year-old White male sustained chronic osteomyelitis secondary to an open middle tibial fracture 1 year ago from a motor vehicle accident. He had a longstanding smoking history. He had chronic drainage from the old fracture site about 2 months previously ( Figs. 44.1 and 44.2 ). He had undergone debridement of the middle tibial wound, removal of hardware, and placement of an external fixator 2 weeks before. The plastic surgery service was consulted for soft tissue coverage of the middle tibial wound, measuring 11 × 7 cm, after the definitive bony fixation by the orthopedic trauma service ( Fig. 44.3 ).

Operative Plan and Special Considerations for Reconstruction

For a typical middle-third wound of the leg with exposed fracture site or hardware, a classic local muscle flap, such as a soleus muscle flap, can be selected to cover the exposed fracture site and hardware. The soleus muscle is a type II muscle flap. However, only a medial hemisoleus muscle has been selected because it is not only able to provide adequate soft tissue coverage but also able to minimize functional loss of the foot plantar flexion. The bipenniform morphology of the soleus muscle and the independent neurovascular supply to either the medial or the lateral belly are important features that allow the surgeon to split the muscle longitudinally. Because the medial hemisoleus muscle is less bulky, the reconstructive outcome is usually much better than when a whole muscle is used as a flap. The medial half of the muscle receives blood supply throughout its length by minor pedicles (perforators) arising from the posterior tibial vessels. This constant feature makes the medial hemisoleus reliable as a proximally based flap.

Operative Procedures

Under general anesthesia with the patient in the supine position, the left middle tibial wound was debrided. All unhealthy-looking skin and colonized tissues were removed. The open tibial wound appeared to be fresh and clean after a definitive debridement performed by the plastic surgery service. The actual soft tissue wound was 11 × 7 cm ( Fig. 44.4 ).

The proposed incision for exposure of the medial hemisoleus muscle flap was marked and the flap dissection was performed under tourniquet control. The existing open wound was extended proximally and distally through the skin, subcutaneous tissues, and fascia to expose the medial hemisoleus muscle. After the medial hemisoleus muscle had been identified and dissected free from the medial gastrocnemius muscle and the flexor digitorum longus, its insertion was divided distally at the level of the Achilles tendon based on the length of the flap rotation required. During dissection, the plantaris tendon was visualized between the gastrocnemius muscle and the underlying soleus muscle. The medial half of the soleus muscle was split along its anatomic midline. The medial hemisoleus muscle flap was elevated with emphasis on the preservation of as many minor pedicles from the posterior tibial vessels as possible to the flap in the middle third of the leg while allowing adequate arc rotation of the flap to cover the exposed tibia and hardware ( Fig. 44.5 ). The flap was then transposed into the middle tibial wound and inset with interrupted 3-0 Monocryl horizontal mattress sutures. Scoring the fascia over the medial hemisoleus muscle belly was also performed to enhance the flap’s arc of rotation for better soft tissue coverage of the tibial wound and hardware ( Fig. 44.6 ).

One drain was placed under the flap and another drain was inserted into the flap donor site. The muscle flap was covered with split-thickness skin grafts. Split-thickness skin grafts were harvested with a dermatome from the left lateral thigh and meshed to 1:1.5 ratio. The incision for the flap exposure was closed in two layers and all skin grafts were secured with skin staples ( Fig. 44.7 ).

Follow-Up Results

The patient did well postoperatively without any issues related to the flap reconstruction for the middle tibial wound closure. He was discharged from hospital on postoperative day 5. His left middle of leg wound healed uneventfully ( Fig. 44.8 ). He was followed by the plastic surgery service for routine postoperative care and underwent an autologous bone graft procedure by the orthopedic trauma service 2 months after flap reconstruction.

Final Outcome

During further follow-up, the left middle tibial wound flap reconstruction site had healed well with good contour and minimal scarring. There was no wound breakdown, recurrent infection, or contour issues related to this soft tissue reconstruction ( Fig. 44.10 ). The patient has resumed his weight-bearing status and has returned to work as a construction worker.

Pearls for Success

A medial hemisoleus muscle flap, not a whole soleus muscle flap, can be used to cover a complex middle tibial wound with the exposed fracture site and hardware. The medial half of the muscle can be split longitudinally along its anatomic midline between the bellies of the soleus muscle. The medial hemisoleus muscle flap is elevated with emphasis on the preservation of as many minor pedicles (perforators) from the posterior tibial vessels as possible to the flap in the middle third of the leg while allowing adequate arc rotation of the flap to cover a wound in the middle third of the leg ( Fig. 44.10 ). In this way, any adjacent perforators from the posterior tibial vessel to the flap can be preserved while allowing adequate arc of flap rotation. Only those perforators that are restricting the flap’s arc of rotation for wound coverage can be divided during the flap dissection. In the author’s practice, a medial hemisoleus muscle flap is a basis for soft tissue reconstruction of the middle-third leg wound. No total flap loss has been observed. Partial flap loss is also uncommon for a proximally based medial hemisoleus muscle flap and can be managed with additional flap advancement after proper debridement.