The "anconeus slide": rotation flap for management of posterior wound complications about the elbow

"Safe dissection parameters of the anconeus rotational flap for soft tissue coverage at the elbow"

Background

The anconeus is a small muscle located on the posterior elbow originating on the lateral epicondyle and inserting onto the proximal-lateral ulna that functions as an elbow extensor as well as dynamic stabilizer. The blood supply is tri-fold: medial/middle collateral artery (MCA), recurrent posterior interosseous artery (RPIA), and less commonly found, the posterior branch of the radial collateral artery. The anconeus has become a popular option for local soft tissue coverage about the elbow (distal triceps, olecranon, proximal forearm). The average defect size for consideration of local anconeus flap coverage is 5-7cm2. The aim of the study was to determine safe dissection parameters of the anconeus as well as map arterial pedicles to achieve successful local harvest of the muscle without devascularization.

Materials and Methods

8 fresh frozen cadaveric arms (all male, average age 63 years - 4 left arms, 4 right arms) from scapula to fingertip were obtained. First, the radial, ulnar and axillary arteries were dissected and isolated. The radial and ulnar arteries were transected. 100cc normal saline was injected through the axillary artery, sequentially clamping the radial followed by the ulnar artery so that adequate flow could be seen through all vessels. 100cc mixture of Biodür and hardener (10:1) was mixed and injected into the axillary artery. We first allowed free flow through both the ulnar and radial vessels followed by clamping of these vessels. This allowed the pressure to build up and fill the smaller vessels in the arms. After injection, the axillary artery was then clamped and the specimens were left to harden for 24-48 h. After hardening, dissection was performed by making a curvilinear incision centred over the lateral epicondyle. The anconeus was identified and the interval between the anconeus and ECU was then confirmed. Measurements of the anconeus muscle were taken. Blunt dissection was carried between anconeus and ECU until the RPIA was identified and protected. We isolated the MCA by dissecting proximally. This was found to run with the nerve to the anconeus. Once this vessel had been protected, the muscle reflected from distal to proximal staying along its ulnar border. The branches of the RPIA were ligated and the dissection was continued proximally. Measurements of the distances of the RPIA, MCA were taken.

Results

The average distance of olecranon to muscle tip was 95.0mm. The average distance of lateral epicondyle (LE) to muscle tip was 90.8mm. The average distance of LE to olecranon was 49.8mm. The average location of the RPIA was 63.mm when measuring LE to vessel, 68.3mm when measuring olecranon to vessel, 18.3mm when measuring RPIA to muscle tip. The average RPIA diameter was 1.1mm and length was 36.4mm from the initial branching of the posterior interosseous artery. The average MCA diameter was 0.7mm. The posterior branch of the radial collateral artery was only found in 3/8 specimens. The RPIA and MCA were constant in all specimens. Dissection was safely carried to the border of the LE and olecranon without disruption of the MCA.

CONCLUSIONS

Our conclusions determined that if dissection of the anconeus is undertaken, the RPIA remains constant between the interval of the ECU as well as anconeus at an average distance of 18.3mm from the tip of the muscle measuring proximally; moreover, the MCA was constant in all specimens found directly between the LE and olecranon always running with the nerve to the anconeus. When dissecting and mobilizing to ensure preservation of the MCA, dissection should be taken from distal to proximal as well as dissecting along the ulnar border of the anconeus. Proximal dissection can be taken as proximal as the border of the LE and olecranon as that did not disrupt MCA blood supply.

Soft-tissue coverage for wound complications following total elbow arthroplasty

Background

In patients with total elbow arthroplasty (TEA), the soft-tissue around the elbow can be vulnerable to soft-tissue complications. This study aims to assess the outcomes after soft-tissue reconstruction following TEA.

Methods

We retrospectively included nine adult patients who underwent soft-tissue reconstruction following TEA. Demographic data and disease characteristics were collected through medical chart reviews. Additionally, we contacted all four patients that were alive at the time of the study by phone to assess any current elbow complications. Local tissue rearrangement was used for soft-tissue reconstruction in six patients, and a pedicle flap was used in three patients. The median follow-up period was 1.3 years (range, 6 months–14.7 years).

Results

Seven patients (78%) underwent reoperation. Four patients (44%) had a reoperation for soft-tissue complications, including dehiscence or nonhealing of infected wounds. Five patients (56%) had a reoperation for implant-related complications, including three infections and two peri-prosthetic fractures. At the final follow-ups, six patients (67%) achieved successful wound healing and two patients had continued wound healing issues, while two patients had an antibiotic spacer in situ and one patient underwent an above-the-elbow amputation.

Conclusions

This study reports a complication rate of 78% for soft-tissue reconstructions after TEA. Successful soft-tissue healing was achieved in 67% of patients, but at the cost of multiple surgeries. Early definitive soft-tissue reconstruction could prove to be preferable to minor interventions such as irrigation, debridement, and local tissue advancement, or smaller soft-tissue reconstructions using local tissue rearrangement or a pedicled flap at a later stage.

Flap survival and functional outcomes in elbow soft tissue reconstruction: A 25-year systematic review

INTRODUCTION

Different elbow flap reconstructions have been described in the literature. We aim to define the optimal flap technique based on defect size and etiology.

METHODS

A systematic review was undertaken using the terms "(Elbow reconstruction) AND ((Soft tissue) OR (flap))". Flaps were grouped under fasciocutaneous (FCF), muscular (MF), distant pedicled (DPF), and free flaps (FF). The primary outcome was flap survival. The secondary outcomes were postoperative complications and range of motion (pROM).

RESULTS

Twenty articles with 224 patients were included. Defect sizes were small (<10 cm²) (18%), medium (10-30 cm²) (23%), large (30-100 cm²) (43%), and massive (>100 cm²) (16%). Etiologies included trauma (26%), burn contractures (26%), infection (26%), hardware coverage (16%), and others (6%). FCF (54%) was the preferred flap followed by MF (28%), DPF (13%), and FF (5%). The rate of flap necrosis was 4% and that of other complications was 10%. The postoperative range of motion (pROM) (reported in 154 patients) was >100°, 50-100°, and <50° in 82%, 17%, and 1% of the cases, respectively. Small defects were most commonly reconstructed with MFs (83%), medium defects were reconstructed with MFs (52%) or FCFs (46%), and large defects were reconstructed with FCFs (91%). Massive defects predominantly required DPFs (60%) and FFs (26%). FCFs were the most common reconstruction method for burn contractures (84%), infections (55%), and traumatic defects (51%). Hardware coverage was predominantly performed using MFs (86%). No difference in complications and pROM was found between flap techniques.

CONCLUSION

Elbow flap reconstruction can be performed using different techniques. FCFs are the most commonly used reconstruction method. MFs are useful for smaller defects and hardware coverage. DPFs and FFs are needed for massive injuries.

Revision total elbow replacement

The range of general and specific adverse event in total elbow arthroplasty is similar in principle and practice to all other revision prosthetic arthroplasty but with three particular challenges: loss of humeral and ulnar bone stock; insufficiency of the extensor 'mechanism'; and the management of the ulnar nerve. Total elbow replacement is presently performed for the management of complex non-reconstructable distal humeral fractures in osteoporotic bone, for post-traumatic arthropathy, and for medically managed inflammatory arthritides in which metaphyseal bone architecture is often preserved while the articular surface is degenerate. In all these conditions the patient often presents for revision total elbow arthroplasty with relevant co-morbidities and relevant musculoskeletal dysfunction (for example: ipsilateral shoulder, wrist, thumb or hand dysfunction). Infection is a universal concern for revision arthroplasty but where the soft tissue 'envelope' is compromised and already limited, as in the proximal forearm, it is difficult to eradicate, particularly in immunocompromised patients. Bone loss compromises subsequent implantation of a revision prosthesis, while failure to restore the working lengths of the humerus and ulna reduces the strength of the flexor and extensor compartment muscles for elbow motion. Failure to restore the continuity of the triceps aponeurosis - antebrachial fascia and triceps medial head-olecranon components of the extensor 'mechanism' also compromises extensor power. Prior triceps-dividing surgical approaches will determine the elasticity, and therefore pliability, of the extensor 'mechanism': this will have a role in determining how much gain in length of the humeral side can be safely achieved. The ulnar nerve, and its management during elbow arthroplasty, is a source of frequent concern, particularly for revision of an elbow arthroplasty undertaken for distal non-reconstructable humeral articular fractures or post-traumatic arthropathy, in which the position of the ulnar nerve is never anatomic. For these reasons revision total elbow replacement (RTER) is challenging: it requires experience with surgical exposures of the elbow including the major nerve trunks, familiarity with the restoration of bone stock, a range of prostheses and techniques for prosthetic implantation, the ability to achieve adequate soft tissue cover and primary closure, and a logical approach to individualised rehabilitation.

Brachioradialis muscle flap for posterior elbow defects: a simple and effective solution for the upper limb surgeon

BACKGROUND

Trauma, infection, and posterior surgical approach are the most frequent causes of soft tissue defects of posterior elbow. The brachioradialis (BR) muscle flap is a rotational muscular pedicled flap, and the dominant vascular pedicle arises from the radial recurrent artery in the proximal portion of the muscle. The aim of the study was to present the BR muscle flap as a simple, safe, and effective solution for the treatment of soft tissue defects of the posterior elbow.

METHODS

Five patients (3 males; mean age, 61.4 years; range, 40-73 years) with soft tissue defects of the posterior elbow underwent surgical treatment with the BR muscle flap. The causes of the defects were total elbow arthroplasty and postsurgical infection (n = 2), 1 patient with elbow arthrodesis due to neuropathic arthropathy, and postsurgical infection after open reduction and internal fixation of olecranon fractures (n = 2). All patients had a BR muscle flap and skin grafting. Orthopedic hardware was removed in 3 cases.

RESULTS

At the mean follow-up of 45 months (range, 26-61 months), all patients had viable and functional soft tissue coverage. All patients were free of infection, whereas 1 patient had a posterior elbow discomfort in daily activities. None of the patients reported wrist problems.

CONCLUSIONS

The BR muscle flap is a reliable solution, easy to harvest without requiring microsurgical expertise for small-size posterior elbow defects. It is a 1-stage procedure with no morbidity to the harvest site that provides stable and adequate coverage even in cases with postoperative infection.

A new local muscle flap for elbow coverage-the medial triceps brachii flap: anatomy, surgical technique, and preliminary outcomes

BACKGROUND

The medial triceps brachii is vascularized by the middle collateral artery and the arterial circle of the elbow. This vascularization allows a distal pedicled use to cover soft tissue defects of the elbow. We report our experience using this flap to cover traumatic and postsurgical wounds.

METHODS

Patients who underwent a pedicled medial triceps brachii flap procedure between 2008 and 2015 were included. Data concerning characteristics of the patients, wound size, surgical technique, and complications were retrospectively reviewed. An independent observer examined patients and assessed outcome of the coverage procedure: wound healing, scar length, range of elbow motion, and patient satisfaction.

RESULTS

Eight patients were included (70.6 ± 17.7 years old at the time of surgery). All patients had serious comorbidities and risk factors of poor wound healing. Defects were due to postoperative healing complications (5 patients), skin necrosis secondary to an underlying olecranon fracture (1 patient), and direct open fractures (2 patients). Soft tissue defects had a median surface of 17 (14-22) cm². The olecranon was exposed in 7 cases and the medial humeral epicondyle in 1 case. Mean procedure duration was 83 ± 14 minutes. There was no intraoperative or postoperative complication. All patients healed properly at 3 weeks of follow-up. No wound recurrence or surgery-related complication was reported after a median follow-up of 40.5 (21.5-69.5) months.

CONCLUSION

Favorable outcomes in all of our 8 patients make this flap an interesting option to cover small to medium-sized defects of the posterior aspect of the elbow.

Effect of Anconeus Muscle Blocking on Elbow Kinematics: Electromyographic, Inertial Sensors and Finite Element Study

The specific contribution of the anconeus muscle to elbow function is still uncertain. This study aimed to investigate the effect on elbow kinematics and kinetics of blocking anconeus using lidocaine. Ten healthy volunteers performed experimental trials involving flexion–extension and supination–pronation movements in horizontal and sagittal planes. Inertial sensors and surface electromyography were used to record elbow kinematics and kinetics and electrical activity from the anconeus, biceps and triceps brachii before and after blocking anconeus. Moreover, a finite element model of the elbow was created to further investigate the contribution of anconeus to elbow kinematics. The electrical activity results from the trials before blocking clearly indicated that activity of anconeus was increased during extension, suggesting that it behaves as an extensor. However, blocking anconeus had no effect on the elbow kinematics and kinetics, including the angular velocity, net torque and power of the joint. The electrical activity of the biceps and triceps brachii did not alter significantly following anconeus blocking. These results suggest that anconeus is a weak extensor, and the relative small contribution of anconeus to extension before blocking was compensated by triceps brachii. The finite element results indicated that anconeus does not contribute significantly to elbow kinematics.

Soft-Tissue Coverage for Elbow Trauma

The elbow is particularly prone to trauma, and soft-tissue reconstruction can be challenging given the inherent motion, pressure, and lack of local tissue laxity. Small wounds and those without exposure of vital structures may be amenable to primary repair. Large wounds and those requiring more substantial structural or anatomic repair may require local, regional or free flap-based reconstruction. A comprehensive review of soft-tissue reconstruction of the elbow is provided to offer surgeons alternative options in complicated upper extremity wounds.

Soft-tissue coverage of olecranon with musculocutaneous flexor carpi ulnaris flap

Coverage of the olecranon area is always challenging in traumatology. Because of the superficial situation of the bone, the absence of muscle, the thinness of the skin and the subcutaneous tissue locally, skin defects are not uncommon and can lead to exposure of hardware or prostheses. We report an original surgical technique using a musculocutaneous flap from the flexor carpi ulnaris (FCU) with a proximal pedicle to cover the olecranon area, detailing its limits and indications. The FCU flap has become our first-choice procedure to cover olecranon skin defects because of its low morbidity, its reliability, and its straightforward procedure, obviating the need for any microsurgery technique. Furthermore, it allows moving the elbow, immediately decreasing the risk of elbow stiffness.

Flexor carpi ulnaris muscle flap for soft tissue reconstruction after total elbow arthroplasty

The soft tissue at the tip of the olecranon is very thin, leading to the frequent occurrence of wound complications after total elbow arthroplasty. To cover a soft tissue defect of the elbow, the flexor carpi ulnaris muscle flap is thought to be appropriate for reconstruction of the elbow with regard to its size, location, and blood supply. We got positive clinical results, so we report our experiences of using a flexor carpi ulnaris muscle flap for soft tissue reconstruction after total elbow arthroplasty.

Wound complications after distal humerus fracture fixation: incidence, risk factors, and outcome

BACKGROUND

This study set out to accurately determine the incidence of wound complications after distal humerus fracture fixation, to assess risk factors, and to determine their implications on outcome.

METHODS

Eighty-nine distal humerus fractures (mean patient age, 58 years) were treated with internal fixation at an average of 4 days after injury. Mean follow-up time was 15 months (range, 6-72 months). Twenty-nine (33%) fractures were open. Medical records and radiographs were reviewed to determine wound complications. Logistic regression analysis was carried out to determine associated risk factors.

RESULTS

Fourteen patients (15.7%) developed a major wound complication requiring on average 2.5 (range, 1-6) additional surgical procedures. Six patients required plastic surgical soft tissue coverage. All 14 fractures complicated by wound problems united. The final mean range of motion in the major wound complication group was 100° (range, 65°-130°), compared with 100° (range, 10°-140°) in those with no or minor wound problems. Grade III open fractures and the use of a plate to stabilize the olecranon osteotomy were identified as significant risk factors for development of major wound complications.

CONCLUSIONS

The incidence of major wound complications after fixation of distal humerus fractures is substantial. The presence of a grade III open fracture and the use of an olecranon osteotomy stabilized with a plate are significant risk factors for major wound complications. Fracture healing rates and functional elbow range of motion do not appear to be affected by major wound complications when they are handled with proper soft tissue coverage techniques.

Anatomic study of the flexor carpi ulnaris muscle and its application to soft tissue coverage of the elbow with clinical correlation

BACKGROUND

The posterior elbow is prone to soft tissue loss that may require reconstructive methods for wound healing to be achieved. The flexor carpi ulnaris (FCU) muscle has been described for coverage in case reports and small series. Previous studies give conflicting anatomic findings about the dominant vascular pedicle for the FCU.

METHODS

Twenty-five cadaveric specimens were dissected. Pedicle location, number, and distance from the medial epicondyle were recorded along with the extent of posterior elbow coverage. Chart review was conducted during a 4-year period. Eight patients who underwent FCU rotational flap coverage were identified. Those flaps relied entirely on a single proximal pedicle.

RESULTS

The vascular pedicles from the ulnar artery or recurrent ulnar artery were identified in 24 of 25 specimens. The average distance from the tip of the medial epicondyle to the first pedicle was 5.7 cm (range, 3 to 10 cm). The length of muscle coverage proximal to the olecranon tip averaged 9.3 cm. The clinical follow-up of 7 patients requiring FCU rotational flaps for coverage of the posterior elbow showed that all flaps survived and provided adequate coverage for the defect.

CONCLUSIONS

The FCU rotational pedicle flap provides predictable coverage of small to medium-sized defects about the posterior elbow. Although it is relatively consistent, the proximal vascular pedicle does demonstrate some variability, which should be considered in planning surgery. The consistent distal extent of the FCU muscle belly provides wider proximal coverage of defects.

Soft-tissue coverage of the elbow

The elbow requires a durable and pliable soft-tissue envelope. Injuries, infections, or tumors that result in exposed tendon, bone, or implants require expedient soft-tissue coverage. Familiarity with various options for coverage can help tailor treatment to the defect size and minimize donor-site morbidity. In this article, emphasis is placed on muscle and fasciocutaneous flaps that have been shown to have reliable vascularity and predictable outcomes.

Functional anconeus free flap for thenar reconstruction: a cadaveric study

BACKGROUND

Restoration of thumb opposition when significant thenar soft tissue defects occur remains a considerable surgical challenge. While several clinical applications of the anconeus muscle have been developed, free functioning muscle transfer (FFMT) of the anconeus for thenar reconstruction has not been reported previously. This study therefore sought to describe anatomical features of the anconeus that would determine its suitability for use as a FFMT.

METHODS

The anconeus, its corresponding abductor pollicis brevis (APB), and the supplying neurovasculature in eight white British cadaveric upper extremities were identified and dissected. Measurements were performed using standard calipers and ImageJ 1.45d for a quantitative description of muscle architecture and the neurovasculature involved in the operative planning of the anconeus FFMT.

RESULTS

The mean measures of the anconeus were larger than those of the APB (anconeus/APB fiber length = 88.0 ± 9.9/57.7 ± 9.0 mm, area = 1,341.9 ± 230.4/987.7 ± 251.2 mm(2)). There was no significant difference between mean fiber angles (anconeus/APB = 70.5 ± 11.9°/78.4 ± 12.2°; p > 0.05) and neurovasculature (anconeus/APB: artery diameter = 1.9 ± 0.2/2.0 ± 0.5 mm, nerve diameter = 1.7 ± 0.3/2.1 ± 0.4 mm; p > 0.05). The length (31.3 ± 6.9 mm) and caliber (diameter = 1.9 ± 0.2 mm) of the vascular pedicle of the anconeus (recurrent posterior interosseous artery) and its venae comitans (diameter = 1.0 mm) are sufficient for microsurgical anastomosis.

CONCLUSIONS

The anatomic rationale of the anconeus FFMT for thenar reconstruction is sound and, compared to other FFMTs, may provide several advantages: reliable and matching anatomy, minimal donor site morbidity, and the potential to restore a greater degree of opposition and thus function in a one-stage procedure.