[Case Report] Humeral Shaft Reconstruction Surgery Following Military Combat Gunshot Injury Using A Titanium Spinal Mesh Cage

 

Source

• Kakkar RS, et al. Int J Surg Case Rep. 2025 Aug 4;134:111772.
  doi: 10.1016/j.ijscr.2025.111772.

 

Background

•       Gunshot injury fractures are particularly difficult to manage due to commonly involving periosteal stripping, extensive soft tissue and bone injury / loss, wound contamination, and open fracture.

•       Among humeral fractures, Grade 3B open fractures are particularly difficult to manage, due to commonly needing multistage treatment: provisional stabilization until wound bed is clean and stable (to reduce risk of infection and nonunion), followed by reconstruction.

•       Segmental bone less especially > 6 cm are particularly challenging.

•       Conventional methods include: Illizarov bone transport, autologous bone grafting, and iliac crest bone grafts.

•       These conventional methods’ drawbacks include prolonged treatment duration, donor site morbidity, variable success rate, and high technical demands.

•       Titanium mesh cages (TMC) is an apparatus originally intended to facilitate spinal reconstruction.

•       In this study, TMC is successfully used to facilitate an autologous bone graft in reconstructing a complex comminuted humeral open fracture on the right side, with extensive segmental bone loss due to ballistic trauma.

 

Case Presentation

•       A 32 year old male Air Force soldier sustained a gunshot injury that left an open wound of 17 x 11 x 4 cm in size in the anterior mid arm during military training.

•       He underwent initial treatment with soft tissue grafts and unilateral rail-type external fixator that managed to stabilize the limb, and was offered a limb-shortening surgery to salvage the limb, an offer he refused.

•       He seeked further treatment 3 months after the initial treatment, which is the focus of this case.

•       Upon examination and imaging (radiography and CT), the patient had completely stiff and nonfunctional right shoulder and elbow, with stabilized soft tissue, and extensive (in this case, 10 cm) unresolved segmental bone gap of his right humerus.

•       Two weeks prior to definitive treatment, the external fixator was removed aseptically and with a post-procedure IV antibiotics to reduce infection risk.

•       External Fixation from Initial Treatment with Residual Bone Defect

•       CT and Radiograph Imaging Prior to Preoperative Planning

Definitive Treatment Sequence

•       General anesthesia

•       A 12-cm ipsilateral fibular autologous bone graft was obtained during a lateral approach.

•       Through a posterior humeral approach, radial nerve was identified, isolated, and protected with a vessel loop.

•       Fracture fragments were found fibrosed and necrotic,

•       Debridement until a bleeding bone edge was found, resulting in a total bone gap of about 10 cm.

•       An 12 mm diameter, 110 mm long titanium spinal mesh cage (TMC, Medtronic, USA) was preoperatively templated.

•       The TMC was manually fitted into the medullary canal of the segmental bone loss in a way that is anatomically aligned, press-fitted into the fracture ends, and packed with the fibular grafts.

•       Fixation was performed using 4.5 mm narrow locking compression plate (DePuy Synthes, Switzerland) to the posterior cortex.

•       The posterior screws were inserted through the bone grafts to increase mechanical stability and prevent toggling.

•       Standard layered wound closure under suction.

•       Postoperative rehabilitation immediately starts day 1 postoperatively, and frequently thereafter, to prevent joint stiffness.

•       Sutures were removed at day 16 postoperatively.

•       At 2 years follow up, the patient presented with full shoulder and elbow range of motion and function, pain-free, without residual instability.

 

Discussion

•       Gunshot injury fractures are particularly devastating, often with:

•       Complex comminuted fractures.

•       Extensive soft tissue and bone loss.

•       Wound contamination.

•       Rail or ring fixators can provide provisional stability before definitive treatment.

Some Techniques To Repair Extensive (> 6 Cm) Bone Defects in Long Bone Fractures

•       Vascularized Fibular Graft (VFG) is considered the gold standard.

•       The graft is osteogenic, osteoinductive, and osteoconductive.

•       Requires microsurgery resources and skills, prolonged procedure, carries donor site morbidity.

•       Extremely unfeasible in resource-limited or rural settings, such as battlefields.

•       Masquelet Technique (Two-stage membrane technique followed with bone grafting).

•       Good results in lower limb reconstruction.

•       Poor results in upper limb due to prolonged procedure and inadequate or delayed membrane formation.

•       Ilizarov Bone Transport.

•       Widely used especially for lower limb.

•       Upper limb often poor results due to insufficient regeneration, pin-tract infections, and joint stiffness, and heavy reliance on patient compliance.

•       Segmental allogenic grafts

•       Provides immediate structural support.

•       Risk of graft rejection, graft resorption, and fatigue failure.

•       Requires access to bone banks and strict infections, commonly unavailable in resource-limited settings.

•       Intercalary endoprosthesis.

•       Primarily used for oncological reconstruction.

•       Immediate functional restoration.

•       Does not have biological incorporation.

•       Risks mechanical failure especially in young, high-demand patients.

•       Simple (nonvascularized) bone grafts are widely used, but has a high risk (up to 20% in bone defects > 6 – 8 cm, especially with suboptimal stabilization and graft integration) of complications:

•       Nonunion, resorption, and fatigue fracture.

•       Segmental allogenic grafts

•       Provides immediate structural support.

•       Risk of graft rejection, graft resorption, and fatigue failure.

•       Requires access to bone banks and strict infections, commonly unavailable in resource-limited settings.

•       Intercalary endoprosthesis.

•       Primarily used for oncological reconstruction.

•       Immediate functional restoration.

•       Does not have biological incorporation.

•       Risks mechanical failure especially in young, high-demand patients.

 

Dual Mechanism (Structural Scaffolding and Bone Grafting) Reconstruction

•       Intramedullary mechanical support (such as scaffolding) can enhance load distribution and reduces micromotion, potentially reducing complication rates of bone grafting.

•       Dual Mechanism (intramedullar scaffolding and bone grafting) was proven superior to simple bone grafting or distraction osteogenesis alone.

•       These scaffolding may be in the form of titanium mesh cages, or custom 3D-printed cages and mesh-sleeves, providing early stabilization and faster rehabilitation, and reduces complication rates.

•       This is the first known case report to use spinal TMC + fibular graft to reconstruct a distal humeral fracture with extensive bone loss.