Vascular bone transfer options in the foot and ankle: a retrospective review and update on strategies

Dedicated locking plate reduces non-union risk in open ankle fusion in obese patients

INTRODUCTION

Obesity is a growing public health concern. In ankle osteoarthritis, non-conservative treatment in advanced stages consists in ankle fusion, or else total ankle replacement, for which obesity is a relative contraindication. One of main complications of ankle fusion is non-union. Devascularization, obesity and fixation material are all factors involved in postoperative non-union, and have to be taken into account in surgical strategy for reliable results. The objective of this study was to compare the rate of ankle non-union in obese patients using quadruple screwing or a dedicated locking plate. The hypothesis was that the locking plate limits the risk of non-union in this population.

METHODS

All patients were obese (BMI>30kg/m2) and presented ankle osteoarthritis with>10° intra-articular deformity. The approach and joint preparation were performed via an anteromedial approach. Group S was composed of 32 patients, operated on by quadruple screwing; group P comprised 10 patients operated on using a dedicated locking plate. The main endpoint was a significant difference in the rate of non-union between the 2 groups. The secondary endpoint was improvement in pre- and 6-month postoperative AOFAS score.

RESULTS

Group S presented 31% non-union (10/32) and group P 0% (0/10) (p<0.05). Postoperative AOFAS score was significantly higher in group P: 67.8±10.4 [range, 40-92] vs. 83.1±8.0 [range, 64-92] (p<0.05).

CONCLUSION

The dedicated anterior locking plate is a technique of choice for ankle fusion in obese patients with intra-articular deformity>10°, to limit the risk of non-union.

LEVEL OF EVIDENCE

IV; retrospective study.

Successful Midfoot Reconstruction in Müller-Weiss Disease Using a Reverse Fibular Flap: A Case Report and Literature Review

Müller-Weiss disease (MWD) is a poorly understood orthopedic condition first described in 1927 that causes chronic pain across the midfoot and hindfoot. The etiology is uncertain but includes navicular dysplasia, osteochondritis, and trauma. The initial management is conservative, aiming to reduce the patient's symptoms, and includes analgesia, footwear, and activity modification. Surgical interventions such as joint fusion are considered when conservative measures fail, but there is little recorded for treatment beyond this. This case outlines the difficult management of a 52-year-old female patient with a long history of MWD. She had no history of previous trauma or neurological problems. A talonavicular fusion failed to unite, resulting in significant necrosis of the lateral navicular and navicular-cuneiform arthritis. We describe the novel use of a reverse vascularized pedicled fibular flap and extended midfoot fusion to manage the navicular bone defect. At six-year follow-up, the patient remains virtually pain-free and has returned to work with radiographs confirming good incorporation of the bone graft. We understand this to be the first documented use of a reverse vascularized fibular bone graft for recalcitrant MWD. Given the excellent clinical outcome in this case, surgeons should consider this combined ortho-plastics approach in the management of complex non-union with a bone defect in the midfoot.

Free Fibular Osteocutaneous Flap Combined With Simultaneous Tendon Reconstruction for Midfoot Restoration After Myoepithelial Carcinoma Resection

ABSTRACT

Myoepithelial carcinomas of soft tissue are rare, and most are malignant. The optimal treatment is surgical excision. The arches of the foot are a composite structure responsible for weight bearing and pressure distribution, so it is a vast challenge in reconstruction. We report a case of reconstruction of the midfoot with a free fibular bone flap and tendon graft. We review the literature to compare various options in foot reconstructions and sort out the outcomes of different bone flaps. The free fibula osteocutaneous flap is the superior choice for midfoot reconstruction owing to its sufficient length, strength, flexible skin paddles, easy-to-withstand osteotomy, and simultaneous tendon graft harvesting.

Treatment of Freiberg's disease using a reverse pedicled metatarsal bone flap: Case report

Despite no surgical procedures receiving unanimous support for treating Freiberg's disease, several surgical treatment options have been described. For the past few years, bone flaps have been shown in children to present promising regenerative properties. We report a novel technique using a reverse pedicled metatarsal bone flap from the first metatarsal to treat one case of Freiberg's disease in a 13-year-old female. The patient presented 100% involvement of the second metatarsal head, with a 6 × 2 mm defect, unresponsive to 16 months of conservative measures. A 7 mm × 3 mm pedicled metatarsal bone flap (PMBF) was obtained from the lateral proximal first metatarsal metaphysis, mobilized and pedicled distally. It was inserted at the dorsum of the distal metaphysis of the second metacarpal towards the center of the metatarsal head, reaching the subchondral bone. Initial favorable clinical and radiological results were maintained for over 36 months during the last follow-up. Based on the powerful vasculogenic and osteogenic properties of bone flaps, this novel technique could effectively induce bone revascularization and prevent further collapse of the metatarsal's head.

Reconstruction of the temporomandibular joint using a vascularized medial femoral condyle osteocartilaginous flap: an experimental investigation in miniature pigs

BACKGROUND

Reconstruction of the temporomandibular joint (TMJ) is a significant challenge in maxillofacial surgery. A vascularized medial femoral condyle (MFC) osteocartilaginous flap is a good choice for TMJ reconstruction. In this study, we evaluated the radiographic and histological changes of MFC after TMJ reconstruction.

METHODS

A ramus-condyle unit (RCU) defect was created unilaterally in five adult male Bama miniature pigs. The ipsilateral vascularized MFC osteocartilaginous flap was used to reconstruct the TMJ, and the non-operative sides served as controls. Multislice spiral computed tomography (CT) was performed preoperatively, immediately postoperatively, and at two weeks, three months, and six months postoperatively. Three animals were euthanized at 6 months postoperatively. Their reconstructed condyles, natural condyles and the MFCs on the opposite side were collected and subjected to µCT and histological evaluation.

RESULTS

In the miniature pigs, the vascularized MFC osteocartilaginous flap was fused to the mandible, thus restoring the structure and function of the RCU. The postoperative radiographic changes and histological results showed that the reconstructed condyle was remodeled toward the natural condyle, forming a similar structure, which was significantly different from the MFC.

CONCLUSIONS

In miniature pigs, the RCU can be successfully reconstructed by vascularized osteocartilaginous MFC flap. The reconstructed condyle had almost the same appearance and histological characteristics as the natural condyle.

The Medial Femoral Condyle Flap: A Novel Versatile Tool for Complex Microvascular Maxillofacial Reconstruction

SUMMARY

The medial femoral condyle flap is well-described for reconstruction of small bone defects of the upper and lower extremities. There are limited case reports of its use in other anatomic sites, particularly for reconstruction of complex head and neck defects. In the setting of previous radiation and contaminated fields, vascularized bone is generally preferred to bone grafts, cadaveric allografts, or synthetic implants. The authors present a case series of complex craniofacial defects involving the midface that were reconstructed using medial femoral condyle flaps, focusing on the type of defect and lessons learned from their early experience to promote awareness of this flap among microsurgeons, who may wish to consider the potential of this flap and incorporate its use into their armamentarium.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Pantalar Arthrodesis

A triple arthrodesis is comprised of subtalar, talonavicular, and calcaneocuboid joints arthrodesis. A pantalar arthrodesis is triple arthrodesis combined with tibiotalar arthrodesis. The goal of the procedure is to obtain a correction of deformity and achieve a plantigrade, functional, painless, stable, weightbearing foot that can be used to ambulate. This is done by creating an osseous continuity across the ankle, subtalar, and talonavicular, and calcaneocuboid joints. There are several approaches and fixation strategies that result in successful clinical union and should be chosen to match the clinical situation. Modern techniques result in high rates of union and pain relief.

Utilization of the Pedicled and Free Fibula Flap for Ankle Arthrodesis

Ankle arthrodesis has become a common surgical procedure for individuals with end-stage ankle arthritis, chronic infection, and bony misalignment. Although arthrodesis is typically managed with arthrodesis in situ or realignment, reconstruction may be utilized for patients with more complicated cases that involve metatarsal defects. Our institution utilizes both the pedicled and free fibula flaps for surgical management pertaining to ankle arthrodesis. Our study looks to evaluate the work of a single plastic surgeon and identify patient postoperative outcomes.

Union Rates of Talar Neck Fractures With Substantial Bone Defects Treated With Autograft

BACKGROUND

This study evaluated the union rate of talar neck fractures with substantial bone defects treated acutely with autologous tibial bone graft during primary osteosynthesis.

METHODS

A case series at a level 1 trauma center was performed to identify consecutive patients who underwent operative fixation of talar neck fracture with autograft (Current Procedural Terminology codes 28445 and 20902) between 2015 and 2018. "Substantial bone defect" was defined as a gap greater than 5 mm in the sagittal plane and greater than one-third of width of the talar neck in the coronal plane. Postoperative foot computed tomographic (CT) scans were obtained for all patients. Primary outcome was union, and secondary outcomes were malunion, avascular necrosis (AVN), post-traumatic arthritis (PTA), and patient-reported outcomes (PROs).

RESULTS

Twelve patients with 12 fractures were included in the series, with an average length of follow-up of 26 months (range: 7-55) The average age was 34 years (17-59), and the most common mechanism of injury was motor vehicle crash. The Hawkins classification of the fractures was 4 type II (2 type IIA and 2 type IIB) (33%) and 8 type III (67%). Four fractures (33%) were open fractures. Union was achieved in 11 patients (92%). There was 1 malunion (8%). AVN was identified on postoperative CT scans in 11 patients (92%). Three of these 11 eventually showed collapse. Ten patients (83%) had radiographic evidence of some degree of ankle PTA, and 12 patients (100%) had radiographic evidence of some degree of subtalar PTA. Average Patient-Reported Outcomes Measurement Information System-Short Form score was 37 (32-45) and average Foot and Ankle Ability Measure activities of daily living and sports subscale scores were, respectively, 61 (31-87) and 31 (0-71), respectively. Average visual analog scale score was 5 (0-10), and average Foot Function Index was 49 (7-89). SF-36 scores showed fair to poor outcomes in the majority of patients.

CONCLUSION

In this relatively small series, tibial autograft in primary osteosynthesis of comminuted talar neck fractures with substantial bone defects is associated with excellent union rates and low malunion rates. Despite high union rates, secondary outcomes of AVN with or without collapse, ankle and subtalar PTA, and relatively low PROs were common.

LEVEL OF EVIDENCE

Level IV, case series.

Avascular Osteonecrosis of the Talus: Current Treatment Strategies

Avascular osteonecrosis (AVN) of the talus (AVNT) is a painful and challenging clinical diagnosis. AVNT has multiple known risk factors and etiologies and presents at different stages in severity. Given these unique factors, the optimal treatment solution has yet to be determined. Both joint-preserving and joint-sacrificing procedures are available, including core decompression and arthrodeses. Recently, new salvage and replacement techniques have been described including vascularized pedicle bone grafts and total talus replacement using patient-specific prosthesis; however, evidence remains limited. This review examines the current trends AVNT treatment and the emerging data behind these novel techniques.

Calcaneal Reconstruction With Free Deep Circumflex Iliac Artery Osseocutaneous Flap Following Aggressive Benign Bone Tumor Resection

BACKGROUND

Advances in limb-salvage techniques have made total calcanectomy and primary reconstruction possible in managing calcaneal aggressive benign tumors and selected cases of intraosseous malignant tumors. However, there is still no consensus on the operative approach, oncologic margin, and the best reconstruction method to date. These 2 cases describe our experience in calcaneal reconstruction with the free deep circumflex iliac artery (DCIA) osseocutaneous flap in benign aggressive calcaneal tumors.

METHODS

We reported 2 consecutive male and female patients, with an average age of 25 years (age 19 and 31, respectively), who underwent total calcanectomy and primary calcaneal reconstruction with the free DCIA osseocutaneous flaps for calcaneal chondroblastoma and giant cell tumor. A marginal resection of the entire calcaneus through the subtalar and calcaneocuboid joints (intra-articular approach) was performed in the first case and a wide local resection leaving 1 cm normal calcaneal bone margin anterosuperiorly (intraosseous approach) was performed in the second case.

RESULTS

The follow-up period averaged 48 months. Negative oncologic margins were achieved in both cases. The first case was complicated with venous thrombosis; however, the graft remained viable after emergency reexploration. Normal foot function was restored with good solid osseous union and bony hypertrophy observed. Both patients achieved good short-term functional and aesthetic outcomes with no donor site pain or disability. No local recurrence was reported either.

CONCLUSION

Primary calcaneal reconstruction with the free DCIA osseocutaneous flap can lead to good short-term functional and aesthetic outcomes.

LEVEL OF EVIDENCE

Level IV, case series.

Management of Chronic Osteomyelitis by an Orthoplastic Team: 7-Year Experience of a University Hospital

BACKGROUND

Treating chronic osteomyelitis of the lower extremities is challenging. The treatment of acute lower limb trauma by orthoplastic teams has shown good results over the past few decades. This study aimed to characterize surgical outcomes of leg and heel chronic osteomyelitis by an orthoplastic team.

METHODS

The cases of 113 consecutive leg and heel chronic osteomyelitis patients undergoing soft-tissue reconstruction with an orthopedic procedure were reviewed in this retrospective single-center observational study. The main objective was to assess surgical outcomes of skin healing and gait recovery at the 1-year follow-up. The secondary objective was to evaluate the global success rate at the last follow-up.

RESULTS

The median follow-up was 19.7 months. A free flap was performed for 33 patients (29.2 percent) and a locoregional flap was used in 79 patients (69.9 percent). Seventy-two patients (63.7 percent) had chronic osteomyelitis on continuous bone. The others had a septic pseudarthrosis with a mean bone defect length of 42.9 mm. Forty-four patients (38.9 percent) underwent curettage only, eight (7.1 percent) underwent curettage and cement, 20 (17.7 percent) underwent curettage and bone fixation, and 39 (34.5 percent) underwent the Masquelet technique. At the 1-year follow-up, 72 patients (63.7 percent) had achieved skin healing and had recovered their gait. The success rate at all follow-up time points was 82.3 percent. The median time to achieve skin healing was 6.5 months and that to bone union in cases of septic pseudarthrosis was 7.9 months.

CONCLUSION

Orthoplastic management of leg and heel chronic osteomyelitis patients with combined soft-tissue reconstruction using an orthopedic procedure was a viable strategy that offered good results even though the time to complete healing was long.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Avascular Necrosis of the First Metatarsal: A Case of Second Metatarsal Bone Transport with External Fixation

Avascular necrosis (AVN) after bunion surgery is an unfortunate complication which can be devastating and painful. We present a case report of gradual medializing transport of the second metatarsal with external fixation to repair a large bone defect caused by AVN affecting >50% of the first metatarsal. The procedure was performed on a 49-year-old female who suffered AVN after failed bunion surgery. At 12-month follow up, first ray position and length were maintained. With respect to the second ray, there were no clinically significant issues. The second digit was mildly elevated but there was no frank instability of the toe or of the Lisfranc complex. The patient was pain free and had returned to her desired daily activities.

Orthoplastic Approach to Lower Extremity Reconstruction: An Update

In order to address complex extremity injuries, the orthoplastic approach uses plastic, orthopedic, and microsurgical techniques and includes other disciplines to optimize limb salvage. This collaboration, if created early in treatment, allows for more expedient and individualized solutions to a variety of extremity injuries resulting in decreased hospital stay, fewer complications, and improved functional outcomes. The orthoplastic approach does not merely avoid amputation, but also improves patient function and quality of life in the short and long term.

Treatment of traumatic losses of substance in the foot

Treatment of traumatic loss of bone and tissue substance in the foot necessitates special consideration of the anatomy and physiology of the segment. The causes of foot trauma are multiple and in many cases violent, leading to progressive tissue deterioration that may require multi-phased debridement. The therapeutic objective is to reconstruct a functional foot permitting painless pushing off, walking and footwear use by restoring a stable bone framework, with resistant covering satisfactorily adjusted to the different zones of the foot. While coverage of the back of the foot must be fine, coverage of the plantar zones will be padded. The reconstructive surgeon shall be particularly attentive to plantar sensitivity. To take up the surgical challenge, it is of paramount importance to fully master a wide-ranging therapeutic arsenal ranging from conventional grafts to composite free flaps in view of proposing the solution most suited to the type, size and location of the loss of substance, all the while striving to generate as few sequelae as possible at the donor site. In order for reconstruction to be successful, multidisciplinary collaboration between plastic surgeons, orthopedists and physician is highly recommended.

Reconstruction of the Weightbearing Area of the Foot with Vascularized Chimeric Osteocutaneous Fibular Flap: A Case Report

Damage to the weightbearing surface of the foot is a challenge for the reconstructive surgeon. The aim is to reconstruct the skeletal tripod and soft tissue, allowing the patient to walk normally. We report the case of a patient admitted with an acute right foot open fracture of the second, third, fourth, and fifth metatarsal bones. After debridement of all nonvital tissues, the patient required reconstruction of the metatarsal heads (third, fourth, and fifth) plus soft tissue coverage. We then performed a reconstruction with a free osteocutaneous fibular flap, insetting the bone perpendicular to the long axis of the metatarsal bones. This configuration allowed the reconstruction of the foot skeletal tripod. A second free flap, a thin radial forearm flap, was added during the revision surgery to improve the venous drainage of the skin paddle of the fibular flap and avoid tension after skin closure. At 1-year follow-up, the patient was able to walk entirely weightbearing on the forefoot, returning to her previous employment with no limitation in physical and recreational activities. To our knowledge, this is the first description of the use of a chimeric osteocutaneous fibular flap, oriented transversely, to reconstruct a complex bone/soft tissue defect after a traumatic loss of multiple metatarsal heads.

Medial Femoral Condyle Free Flap Reconstruction of Complex Foot and Ankle Pathology

Background:

Complex hindfoot pathology may benefit from vascularized bone flap reconstruction rather than traditional bone grafting techniques. Medial femoral condyle (MFC) flaps provide vascularized periosteum, skin, and corticocancellous bone.

Methods:

A retrospective, single-institution cohort study of consecutive MFC flaps performed for complicated hindfoot reconstruction between 2013 and 2019 was reviewed. Radiologic follow-up assessed osseous union and clinical outcomes were evaluated with the American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score. Thirty MFC flaps were performed in 28 patients for complex hindfoot pathology. Twenty-seven flaps had adequate clinical and radiographic follow-up (mean 15.8 months).

Results:

The majority presented with avascular necrosis (83%) and failed prior operations (67%, mean 3.1). Most hindfoot procedures involved arthrodesis (n = 24, 80%); tibiotalocalcaneal (n = 11) and talonavicular (n = 7) most frequently. Mean osseous flap volume was 10.3 cm3 (range 1.7-18.4 cm3); one flap required takeback for venous congestion but no total flap losses occurred. Primary osseous union was initially achieved in 20 patients (74%, mean 217 days). Six flaps developed interface nonunion; 5 underwent revision arthrodesis and ultimately achieved union in 24/27 flaps (89%, mean 271 days). Risk factors for nonunion were body mass index (BMI) >30 ( P = .017) and prior arthrodesis ( P = .042). Mean AOFAS hindfoot scores increased significantly from 52.3 preoperatively to 70.7 postoperatively ( P < .001). Subscore analysis demonstrated significant improvement in postoperative pain scores from 14.2 to 27.3 out of 40 ( P < .001).

Conclusion:

The MFC free flap provided vascularized bone for complicated foot and ankle reconstruction with relatively low donor site morbidity, promising osseous union results, and improved functional outcomes.

Level of Evidence:

Level IV, retrospective case series.

The Use of Bone Grafts, Bone Graft Substitutes, and Orthobiologics for Osseous Healing in Foot and Ankle Surgery

Achieving fusion in osseous procedures about the foot and ankle presents unique challenges to the surgeon. Many patients have comorbidities that reduce osseous healing rates, and the limited space and high weightbearing demand placed on fusion sites makes the choice of bone graft, bone graft substitute, or orthobiologic agent of utmost importance. In this review, we discuss the essential characteristics of grafts, including their osteoconductive, osteoinductive, osteogenic, and angiogenic properties. Autologous bone graft remains the gold standard and contains all these properties. However, the convenience and lack of donor site morbidity of synthetic bone grafts, allografts, and orthobiologics, including growth factors and allogenic stem cells, has led to these being used commonly as augments.

Management of Post-Traumatic Composite Bone and Soft Tissue Defect of Leg

Management of composite defects of leg following trauma requires a planned ortho-plastic approach right from the outset. Timely, planned intervention results in reduced amputation rates and improved limb salvage and function. Right from the time of presentation of the patient to the emergency with such injury, the process of decision making in terms of salvage or amputation, local flap cover/free flap cover, bone reconstruction first or soft tissue or both combined, come into play. Guidelines on management are unclear for such defects, a literature search yielding various methods being used by different authors.

This article is a review of current literature on management of composite leg defects.

A summary of the literature search in terms of various management options given by various authors including the rationale, advantages and disadvantages of each strategy has been provided in this article. The management protocol and method followed by the author in his institute for management of such composite defects have been described in detail. The article seeks to provide readers with an understanding of the management strategies so that appropriate method could be chosen to provide best result.

An Innovative Application of the Free Vascularized Medial Femoral Condyle Flap in the Prevention of Recurring Neuropathic Ulcer in the Diabetic Foot: A Case Report

Despite various therapy options, the prophylactic and symptomatic treatment of recurrent ulcerations in the diabetic foot are still challenging. We report the application of a free vascularized medial femoral condyle flap to prevent the recurrence of pressure ulcer in a patient with diabetic foot syndrome. Our patient had type 2 diabetes and presented with pressure ulcers and osteomyelitis of metatarsal heads 2 and 3 after a great toe amputation. We chose to use a medial femoral condyle flap as a damper in the area of the metatarsal heads because of the relatively young age and good vascularity of our patient. We shaped the graft like a ski to distribute the pressure and prevent perforation of the plantar skin. Good results were achieved for wound healing, pain reduction, and improvement of gait. No pressure ulceration had recurred after a 3-year follow-up period. The versatility of the osteomyocutaneous graft from the medial femoral condyle is an important reconstructive tool for addressing major surgical problems. We present the first use of a medial femoral condyle flap in the treatment of a pressure ulcer in a diabetic foot. In selected patients, our method could prevent premature and extended amputations, thereby providing good improvement in patients' quality of life.

Donor-Site Morbidity of Vascularized Bone Flaps from the Distal Femur: A Systematic Review

BACKGROUND

Vascularized grafts from the femur, including the medial femoral condyle and medial femoral trochlea, are increasingly being used. It is critical to understand the lower extremity complications from flap harvest.

METHODS

The authors searched available literature reporting on femoral flaps using PubMed, Embase, Cochrane Database, and Web of Science. After article selection, data were collected regarding demographics, procedure details, outcomes, and complications. The authors classified outcomes as good, fair, or poor based on pain, range-of-motion, sensory changes, subjective reporting, patient-reported outcomes, and other donor-site complications, including the need for additional procedures.

RESULTS

Two hundred twenty articles were identified. Forty-five met criteria for review, with data available for 283 patients. No patients had range-of-motion deficits beyond 1 year. Two percent of patients (six of 283) required additional donor-site procedures, with one report of a femur fracture after medial femoral condyle harvest. Only one study on 45 medial femoral trochlea patients presented patient-reported outcomes regarding the knee. Few objective data were presented. Twenty-eight articles presented adequate complication data for 252 patients to be rated as good, fair, or poor. Overall, 89 percent had good outcomes without donor-site complications. Of the 176 medial femoral condyle patients with outcomes reported, 92 percent had good outcomes; and 71 percent of the 48 medial femoral trochlea patients had good outcomes reported.

CONCLUSIONS

Overall, the reported donor-site morbidity from medial femoral condyle and medial femoral trochlea harvest is low. Chronic knee pain and sensory changes are most frequently reported, especially in medial femoral trochlea patients.

The Medial Femoral Condyle Corticoperiosteal Free Flap for Frontal Sinus Reconstruction

Although the medial femoral condyle has been used for reconstruction in various areas of the body, to the authors' knowledge it has not been used for frontal sinus reconstruction. The authors describe a novel approach to a complex patient using the medial femoral condyle cortiocoperiosteal free flap to reconstruct an anterior frontal sinus defect in conjunction with a recalcitrant mucocele.

Stem cell therapy in early post-traumatic talus osteonecrosis

PURPOSE

Avascular necrosis of the talus is one of the most notable complications associated with talar neck fractures with frequent evolution of the osteonecrosis into a difficult arthrodesis. We tested whether the injection of bone marrow mesenchymal stem cells (MSCs) could improve the repair process of the osteonecrosis.

MATERIAL AND METHODS

Forty-five early (without collapse) post-traumatic talus osteonecroses (group 1; study group) were treated between 1995 and 2012 with percutaneous injection of progenitor cells (autologous bone marrow concentrate from the iliac crest). The number of MSCs transplanted in each ankle of group 1 was 124 × 103 cells (range 101 × 10³ to 164 × 10³ cells). The evolution of these osteonecroses treated with autologous bone marrow implantation was compared with the evolution of a control group of 34 talar osteonecroses without collapse and treated with only core decompression (group 2; control group) between 1985 and 1995. The outcome was determined by progression in radiographic stages to collapse, by the need of arthrodesis, and by the time to successfully achieve fusion for patients who needed arthrodesis.

RESULTS

For the 45 ankles with autologous concentrate bone marrow grafting, collapse frequency was lower (27%, 12 among 45 versus 71%, 24 among 34; odds ratio 0.1515, 95% CI 0.0563-0.4079; P = 0.0002) and follow-up showed longer duration of survival before collapse or arthrodesis, compared to 34 ankles of the control patients with core decompression alone. Furthermore, the time to successfully achieve fusion after arthrodesis was significantly shorter in patients treated with bone marrow progenitors as compared with the other ankles, which had core decompression alone.

CONCLUSION

In our study the early conservative surgical treatment with autologous bone marrow grafting improved the natural course of the disease as compared with core decompression alone.

Medial Femoral Condyle Microvascular Bone Transfer as a Treatment for Capitate Avascular Necrosis: Surgical Technique and Case Report

Avascular necrosis (AVN) of the capitate is a rare clinical entity for which a variety of treatment options have been described, ranging from immobilization to microvascular bone transfer. Outcomes following medial femoral condyle corticocancellous free flap reconstruction have not been reported for this specific pathology. We present the case of a 16-year-old girl with posttraumatic capitate AVN who was treated with curettage and medial femoral condyle corticocancellous vascularized bone grafting. At 18 months after surgery, the patient remains pain-free and had resumed all activities including lifeguarding by 6 months after surgery. This microsurgical technique, described previously for AVN of the scaphoid and lunate, may be applied in a similar fashion for the capitate with promising clinical results.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Vascularized Pedicle Bone-Grafting from the Cuboid for Talar Osteonecrosis: Results of a Novel Salvage Procedure

BACKGROUND

Osteonecrosis of the talar body represents a complex clinical challenge with treatment options currently limited to core decompression, vascularized and nonvascularized bone-grafting, total talar replacement, and hindfoot arthrodesis. Vascularized pedicle bone-grafting from the cuboid to the talus is a potential alternative to contemporary operative options for replacement of necrotic talar tissue with viable bone. We aimed to analyze functional and radiographic outcomes of vascularized pedicle bone-grafting from the cuboid for the treatment of talar osteonecrosis in a consecutive series of patients spanning a 12-year period.

METHODS

Patients with osteonecrosis of the talar body and dome who underwent vascularized pedicle bone-grafting from the cuboid to the talus at our institution between 2003 and 2014 were retrospectively identified. All patients had preoperative radiographs and magnetic resonance imaging (MRI) scans and were monitored postoperatively with serial radiographs and MRI. For generic health-related quality-of-life (HRQoL) assessment, patients were given the preoperative Medical Outcomes Study Short Form-12 (SF-12) and postoperative 36-Item Short Form (SF-36) from which Physical Component Summary (PCS) and Mental Component Summary (MCS) scores were derived and compared before and after surgery.

RESULTS

Thirteen patients were identified and sequentially followed for 2 to 12 years (mean, 6 years). Two patients had failure of treatment and subsequently underwent total ankle replacement, 1 patient had arthroscopic debridement for soft-tissue impingement, and no other patient required secondary surgery. The average PCS score (and standard deviation) significantly improved by 23.3 ± 18.9 points with surgery (p = 0.006), and the average MCS score significantly increased by 39.4 ± 10.1 points (p < 0.001).

CONCLUSIONS

HRQoL outcomes suggest that vascularized pedicle bone-grafting from the cuboid combined with bracing for 1 year may be a viable treatment option for osteonecrosis of the talus that provides good pain relief and improved physical function without necessitating a secondary procedure for the majority of patients.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Surgically‑induced mouse models in the study of bone regeneration: Current models and future directions (Review)

Bone regeneration has been extensively studied over the past several decades. The surgically‑induced mouse model is the key animal model for studying bone regeneration, of the various research strategies used. These mouse models mimic the trauma and recovery processes in vivo and serve as carriers for tissue engineering and gene modification to test various therapies or associated genes in bone regeneration. The present review introduces a classification of surgically induced mouse models in bone regeneration, evaluates the application and value of these models and discusses the potential development of further innovations in this field in the future.

The effect of ankle posture on the load pathway through the hindfoot

The foot–ankle complex is frequently injured in a wide array of debilitating events such as car crashes. Numerical models and experimental tests have been used to assess injury risk, but most do not account for the variations in ankle posture that frequently occur during these events. In this study, the positions of the bones of the foot–ankle complex (particularly, the hindfoot) were quantified over a range of postures. Computed tomography scans were taken of a male cadaveric leg under axial loading with the ankle in five postures in which fractures are commonly reported. The difference in the location of the talus and calcaneus between the neutral and each repositioned posture was quantified, and substantial rotations and displacements were observed for all postures tested (talus: 3°–21.5°, 1.5–10.5 mm; calcaneus: 10°–20°, 1.5–24.5 mm). Strains were also recorded at six locations on bones of the ankle during testing and were found to be highest in the calcaneus during inversion-external rotation and highest in the talus during eversion-external rotation. Postural changes likely affect the load pathway of the foot–ankle complex, potentially altering the stress and strain fields from that of the neutral case and changing the location of fracture. This highlights the need for injury-predicting studies examining the effect of these positional changes and to develop revised injury criteria accounting for the most vulnerable conditions.

Use of fibula flaps to treat persistent talonavicular nonunion: A report of three cases

Owing to the limited blood supply in the midfoot, multiple arthrodesis attempts in midfood joints may result in severe osteonecrosis, leading to a difficult scenario for bone reconstruction. This article describes the use of fibula flaps (two free and one pedicled flap) to reconstruct bone defects in three cases of persistent nonunion in midfoot joints. Before admission, all patients (aged 32-56 years old) had undergone multiple arthrodesis attempts (range 3-4) aimed at treating joint diseases associated with flatfoot or Müller-Weiss syndrome. All inserted flaps were stable, and bone fusion was confirmed by X-ray examination at month 4. After the follow-up period (range 1-4 years), all patients showed normal, painless gait. No foot deformities or further complications were observed. Our report suggests that fibula flap transfer may be a good alternative for treating persistent nonunion in midfoot joints involving bone loss, and may prevent the osteonecrosis associated with limited blood supply. © 2016 Wiley Periodicals, Inc. Microsurgery 36:430-434, 2016.

Subtalar fusion with iliac bone free flap after a recalcitrant nonunion: Report of two cases

Fractures of the calcaneus are associated with secondary osteoarthritis of the subtalar joint. In a persistent nonunion, vascularized bone flaps offer superior biologic and mechanical properties as well as accelerates joint fusion and decreases morbidity. In this report, we present results of the use of vascularized iliac bone free flap for treating subtalar failed fusions in two patients. Two patients sustained calcaneal fractures due to foot trauma, which were initially or subsequently treated with subtalar arthrodesis. Case one developed septic subtalar nonunion during treatment and case two failed three attempts at subtalar arthrodeses. The iliac crest bone flap harvested measured 4 × 4 cm (case one) and 3 × 3 cm (case two). The flap was pedicled by the deep circumflex iliac artery, which was anastomosed to the anterior tibial artery at the recipient site. No flap donor or recipient site complications occurred. Fusion was confirmed on CT scan and weight bearing was initiated at 5-6 months. At latest follow up (1-2 years), no complications occurred. Our results show that subtalar nonunion treatment with a vascularized iliac bone flap may be feasible and such a reconstruction could be clinically successful. © 2015 Wiley Periodicals, Inc. Microsurgery 36:501-506, 2016.

A new form of surgical treatment for patients with avascular necrosis of the talus and secondary osteoarthritis of the ankle

A new method of vascularised tibial grafting has been developed for the treatment of avascular necrosis (AVN) of the talus and secondary osteoarthritis (OA) of the ankle. We used 40 cadavers to identify the vascular anatomy of the distal tibia in order to establish how to elevate a vascularised tibial graft safely. Between 2008 and 2012, eight patients (three male, five female, mean age 50 years; 26 to 68) with isolated AVN of the talus and 12 patients (four male, eight female, mean age 58 years; 23 to 76) with secondary OA underwent vascularised bone grafting from the distal tibia either to revascularise the talus or for arthrodesis. The radiological and clinical outcomes were evaluated at a mean follow-up of 31 months (24 to 62). The peri-malleolar arterial arch was confirmed in the cadaveric study. A vascularised bone graft could be elevated safely using the peri-malleolar pedicle. The clinical outcomes for the group with AVN of the talus assessed with the mean Mazur ankle grading scores, improved significantly from 39 points (21 to 48) pre-operatively to 81 points (73 to 90) at the final follow-up (p = 0.01). In all eight revascularisations, bone healing was obtained without progression to talar collapse, and union was established in 11 of 12 vascularised arthrodeses at a mean follow-up of 34 months (24 to 58). MRI showed revascularisation of the talus in all patients. We conclude that a vascularised tibial graft can be used both for revascularisation of the talus and for the arthrodesis of the ankle in patients with OA secondary to AVN of the talus.