Lower extremity muscle perforator flaps for lower extremity reconstruction

A true muscle perforator flap is distinguished by the requisite intramuscular dissection of its musculocutaneous perforator to capture the same musculocutaneous territory but with total exclusion of the muscle, and thereby results in minimal functional impairment. Adhering to this definition, several lower extremity donor sites now are available, each with specific attributes especially useful for consideration in the treatment of lower extremity defects. In this author's experience over the past two decades, 20 lower extremity muscle perforator flaps using multiple donor sites proved advantageous for lower extremity coverage problems as either a local pedicled flap or as a microsurgical tissue transfer. Significant complications occurred in 30 percent of flaps (six of 20) in that further intervention was required. Venous insufficiency and bulkiness were found to be the major inherent shortcomings. However, giant flaps, lengthy and large-caliber vascular pedicles, and the possibility for combined flaps were important assets. The choice of a lower extremity muscle perforator flap for lower extremity reconstruction limited the surgical intervention and morbidity to a single body region.     

Upper extremity microsurgery

Learning objectives: After studying this article, the participant should be able to: 1. Understand the indications for free flap coverage of the upper extremity. 2. Know the advantages and disadvantages of the flaps discussed. 3. Have a basic understanding of the anatomy of the flaps discussed. 4. Have a variety of options for free tissue transfer.The application of microsurgical tissue transfer to reconstruction of the upper extremity allows repair of significant bone and soft-tissue defects. Through the years the approach has changed from one of simply getting the wound covered to primary reconstruction to preserve or regain function. A wide variety of free flaps offers the potential to reconstruct nearly any defect of the arm and hand. Vascularized bone transfer can be utilized to repair large bony defects, while innervated free muscle transfer can replace missing muscle function. The total array of flaps and their indications is beyond the scope of a single discussion, but this article focuses on a few flaps that have found application for coverage and functional restoration in the hand and upper extremity.     

Bone reconstruction of the lower extremity: complications and outcomes

A study was performed to analyze the results and final outcomes of bone reconstruction of the lower extremity. Twenty-six patients presented with type IIIB open fractures, nine with type IIIC open fractures, and 15 with chronic osteomyelitis. Seven patients underwent primary amputation, and reconstruction was attempted for 43 patients. The mean bone defect size was 7.7 cm (range, 3 to 20 cm). Bone reconstruction was achieved with conventional bone grafts in 16 cases, in association with either local (13 cases) or free (three cases) flaps. Vascularized bone transfer was performed in 24 cases, with either osteocutaneous groin flaps (10 cases), soleus-fibula flaps (12 cases), or osteocutaneous lateral arm flaps (two cases). For three patients, bone reconstruction was performed with a technique that combines the induction of a membrane around a cement spacer with the use of an autologous cancellous bone graft. Infections were observed to be responsible for prolonged hospital stays and treatment failures. The cumulative rates of sepsis were 4.6 percent at 1 week after injury and 62.8 percent at 2 months. Vascular complications were also related to infections and were responsible for four secondary amputations. One patient asked for secondary amputation because of a painful nonfunctional lower limb. Bone healing occurred in 37 of 43 cases, and the average time to union was 9.5 months, with an average of 8.7 procedures. The mean lengths of stay were 49 days for conventional bone grafts and 62 days for vascularized bone grafts. All of the 50 patients were able to walk, with an average time of 14 months. All of the patients with amputations underwent prosthetic rehabilitation. Patients mostly complained about the reconstructed limb (62.8 percent). Joint stiffness was present in 40 percent of the cases. Other long-term complications were pain (nine cases), lack of sensation (five cases), infection (five cases), and pseudarthrosis (one case). However, all of the patients with successful reconstructions preferred their salvaged leg to an amputation. Of 41 patients who were working before the injury, 26 returned to work.     

Lower extremity microsurgical reconstruction

LEARNING OBJECTIVES: After studying this article, the participant should be able to: 1. Understand the indications for the use of free-tissue transfer in lower extremity reconstruction. 2. Understand modalities to enhance the healing and care of soft tissue and bone before free-tissue transfer. 3. Understand the lower extremity reconstructive ladder and the place of free-tissue transfer on the ladder. 4. Understand the specific principles of leg, foot, and ankle reconstruction. 5. Understand the factors that influence the decision to perform an immediate versus a delayed reconstruction. Free-tissue transfer using microsurgical techniques is now routine for the salvage of traumatized lower extremities. Indications for microvascular tissue transplantation for lower extremity reconstruction include high-energy injuries, most middle and distal-third tibial wounds, radiation wounds, osteomyelitis, nonunions, and tumor reconstruction. The authors discuss the techniques and indications for lower extremity reconstruction.     

Stump-socket pressure in lower extremity prostheses

The pressures existent at the interface between stump and socket were obtained for two subjects equipped with above the knee prostheses. The effects of leg alignment changes and the passage of time are detailed in terms of local dynamic pressures experienced while walking.

Local instantaneous pressures vary from 0 to 50 psi as a function of location, subject and gait phase. Highest pressures are obtained at the socket brim. Alignment changes produce but small pressure changes. Maximum donning pressures equal those in walking: standing pressures are less than half of peak walking pressures.     

The treatment of lower extremity sarcomas with wide excision, radiotherapy, and free-flap reconstruction.

Treatment of extremity sarcomas has evolved into a multidisciplinary approach utilizing surgery, radiotherapy, and, in some cases, chemotherapy. Limb-sparing surgery has maintained low rates of local recurrence when supplemented with early postoperative radiotherapy (brachytherapy). Leg defects that result from resection resemble those caused by trauma and appear ideally suited to free-flap reconstruction. However, the resection site is subjected to 4500 cGy of radiation given within 2 weeks of surgery. It has not been demonstrated that free flaps can endure early postoperative radiation without adverse effects. Three patients are presented with locally recurrent leg sarcomas treated by wide excision, brachytherapy, and free-flap reconstruction. All flaps survived, and the wounds healed uneventfully. This study reviews the current multidisciplinary approach to the treatment of lower extremity sarcomas and demonstrates the durability of free-flap reconstruction in the presence of early postoperative radiation therapy.     

Bicycle spoke injuries in the lower extremity

This study reports the authors' 5-year experience with treating lower extremity injuries in bicycle passengers caused by the spokes. This patient group was selected from 716 lower extremity injuries that received treatment at our outpatient plastic surgery clinic. A total of 26 patients were treated during the study. Patients ranged from 2 to 19 years old, with a mean age of 5.6 years. The authors treated more female passengers (62 percent) than male passengers. The right foot (52 percent) was involved more often than was the left. Most patients were injured in the afternoon, from 2 to 7 PM (62 percent), and between May and October (77 percent). The rear wheel (89 percent) injured the majority of patients. The Achilles tendon was the most common site of injury (63 percent). The typical types of wounds observed included the following: type I, laceration with partial avulsion of skin and subcutaneous tissue (41 percent) and laceration forming a distally based flap (33 percent); type II, abrasions with ecchymoses and friction burn from the shearing effect of the spokes creating a partial- to full-thickness skin defect (26 percent). Of the type I injuries, full-thickness skin lacerations (33 percent) were closed primarily. Partial-thickness skin lacerations, abrasions, ecchymoses, and skin defects (67 percent) were treated conservatively with wound irrigation and dressing. The wound healing time for type I injuries was 29 days; for type II injuries, it was 27 days. These healing times were prolonged compared with healing by first intention. No significant difference was found in healing time when comparing both types of injury. Four patients required hospitalization. No patient required skin grafting. No fractures were noted because these patients were selected from the outpatient plastic surgery clinic and did not include patients from the emergency room. Since the first report of bicycle spoke injuries a half-century ago, prevention has not improved.     

On physiological edema in man's lower extremity

To examine whether the so-called musculovenous pump counteracts the development of interstitial edema in the lower extremities of man in the upright position, the volume changes in the calf which occurred during twenty minutes of rhythmic muscular exercise were measured in twenty-three subjects by impedance-plethysmography. The results were compared with the volume increase found during quiet relaxed standing for the same length of time. Contrary to the hypothesis, and edema-protective effect of the musculovenous pump could only be shown in about half the number of the subjects. In the others, muscular exercise led to increases in calf volume which were higher than those measured in the normal upright position. These results show that the calf muscle pump does not generally have a edema-protective effect but rather that muscle contractions also activate mechanisms which stimulate the extravasation of fluid. In a second test-series with twenty subjects, changes in calf volume were measured during the course of the day. In nearly all cases, the calf volume was greater in the evening than in the morning. It could be shown that the volume increases in the evening are caused by an increase in extravascular fluid. Compared to the increase in extravascular volume occurring during twenty minutes, in a normal upright position, the accumulation of extravascular fluid during the day is, however, remarkably low. Although it is still unknown how interstitial edema in man's lower extremities is prevented during the day, these findings lead to the hypothesis that the edema-preventing mechanisms, for instance the muscle-lymphpump, do not become maximally effective until a certain volume has accumulated in the interstitial space.