Medial Femoral Condyle Periosteal Free Flap for the Treatment of Talus Avascular Necrosis

Medial Femoral Condyle Free Flap: A Systematic Review and Proportional Meta-analysis of Applications and Surgical Outcomes

Background

Recalcitrant bone nonunion and osseous defect treatment is challenging and often requires vascularized bone transfer. The medial femoral condyle flap has become an increasingly popular option for reconstruction. The study aims at reviewing its different applications and synthesizing its surgical outcomes.

Method

A systematic review including all studies assessing surgical outcomes of free medial femoral condyle flap for bone reconstruction in adults was conducted on January 31, 2023. Flap failure and postoperative complications were synthesized with a proportional meta-analysis.

Results

Forty articles describing bony reconstruction in the head and neck, upper limb, and lower limb areas were selected. Indications ranged from bony nonunion and bone defects to avascular bone necrosis. Multiple flaps were raised as either pure periosteal, cortico-periosteal, cortico-cancellous-periosteal, or cortico-chondro-periosteal. A minority of composite flaps were reported. Overall failure rate was 1% [95% confidence interval (CI), 0.00-0.08] in head & neck applications, 4% in the lower limb (95% CI, 0.00-0.16), 2% in the upper limb (95% CI, 0.00-0.06), and 1% in articles analyzing various locations simultaneously (95% CI, 0.00-0.04). Overall donor site complication rate was 4% (95% CI, 0.01-0.06). Major reported complications were: femoral fractures (n = 3), superficial femoral artery injury (n = 1), medial collateral ligament injury (n = 1), and septic shock due to pace-maker colonization (n = 1).

Conclusion

The medial femoral condyle flap is a versatile option for bone reconstruction with high success rates and low donor site morbidity.

Treatment of Infected Nonunions With Bone Defects Using Autologous Bone Graft and Absorbable Antibiotic-Loaded Calcium Sulfate-Hydroxyapatite Paste

BACKGROUND

Revision surgery in the presence of infection carries high risks. We describe our results using a new technique to treat these challenging problems. We treated infected nonunions with cavitary voids with adjuvant antibiotic loaded calcium sulfate-hydroxyapatite paste composite and autologous bone graft (ABG) layer technique coupled with stable fixation.

METHODS

Thirty consecutive patients who underwent revision foot and ankle surgery for an infected nonunion were prospectively studied. Following multidisciplinary team workup, surgical debridement and biopsies were undertaken. Bone voids were measured and classified according to containment and size. ABG was mixed and layered with an adjuvant antibiotic-loaded calcium sulfate-hydroxyapatite paste followed by surgical reconstruction including arthrodesis and fixation. Empirical and pathogen-specific antibiotics were instituted until intraoperative sample-specific antibiotics were identified and used. Patients were prospectively followed up for a minimum of 1 year.

RESULTS

The male-female ratio was 16:14, mean age was 51.3 years, and 23.3% smoked at definitive surgery. Void volume was <1 cm³ (n=9), 1-2 cm³ (n = 13), and >2 cm³ (n=8). No patients either were lost to follow-up or had a further infective episode at a mean of 38.3 months; 86.7% united with fusion on imaging. Four patients had radiographic evidence of nonunion; 3 were asymptomatic and 1 required revision surgery (void >2 cm³). Independent ambulation was achieved at an average of 12 weeks, at 1 year mean American Orthopaedic Foot & Ankle Society score was 77.7 (SD 9.59), and the Manchester-Oxford Foot Questionnaire reached an effect size >0.5 in all domains at 1 year following surgery. The union rate was independent of smoking status and vitamin D deficiency (P = .94).

CONCLUSION

Layered autologous bone grafting with adjuvant antibiotic-loaded calcium sulfate-hydroxyapatite paste has been shown to be effective and safe in revision arthrodesis, with low comorbidities in void gaps without infection recurrence.

Biologic Augmentation of Tibiotalocalcaneal Arthrodesis With Allogeneic Bone Block Is Associated With High Rates of Fusion

BACKGROUND

The orthopaedic conditions and systemic comorbidities that occur in patients who require bone block tibiotalocalcaneal (TTC) arthrodesis have made this procedure associated with a higher-than-normal risk of nonunion, graft collapse, hardware failure, and amputation. Here, we present a novel approach to bone block TTC arthrodesis using adjunctive osteoinductive agents and a prolonged course of protected weightbearing to assess if we could improve on historical outcomes. We also evaluated the efficacy of a vascularized medial femoral condyle (MFC) free flap to augment TTC arthrodesis.

METHODS

Fourteen adult patients underwent bone block TTC arthrodesis biologically augmented with fresh-frozen femoral head allograft, bone marrow aspirate concentrate, and demineralized bone matrix cortical fibers. Three patients with soft tissue defects underwent vascularized reconstruction with an MFC free flap. Radiographic union, the Foot Function Index (FFI), and PROMIS pain interference (PI), and physical function (PF) scores were assessed at follow-up.

RESULTS

TTC fusion was documented on plain radiograph in 13 of 14 patients (92.9%) and CT in 10 of 11 patients (90.9%). Mean time to fusion was 183.2 ± 83.2 days. One patient (7.1%) experienced nonunion and persistent infection requiring amputation. Patients who underwent vascularized bone grafting had significantly shorter time to fusion (112.3 ± 31.7 days vs 204.4 ± 82.7 days, P = .05). Patient-reported outcomes revealed mild to moderate pain and dysfunction after 1 year (mean FFI = 41.0% ± 23.1%, PROMIS PI = 58.3 ± 1.8, PROMIS PF = 39.0 ± 2.2).

CONCLUSION

In this relatively small series, the biologic augmentation of bone block TTC arthrodesis with osteoinductive agents and protective weightbearing resulted in excellent rates of fusion, modest pain, and preserved function of the lower extremity in almost all those treated. Osseous healing appears to be enhanced and accelerated with application of an MFC flap. We believe that this approach offers a viable salvage option for these challenging clinical problems.

LEVEL OF EVIDENCE

Level IV, case series.