Collagen, Bone Wax or Compression for Cancellous Bone Bleeding After Single-Ray Amputation

A Prospective, Randomized, Controlled, Assessor-Blinded, Three-Arm Clinical Trial Comparing Fibrillar Type-I Collagen Haemostat, Bone Wax, and Standardized Compression for Control of Cancellous Bone Marrow Bleeding Following Single-Ray Amputation

This is a prospective, three-arm, parallel-group randomized controlled clinical trial evaluating fibrillar Type-I collagen haemostat, conventional bone wax, and standardized compression alone for control of bleeding from exposed cancellous bone following single-ray amputation. Adults undergoing single-ray amputation involving the phalanx, metacarpal or metatarsal will be randomized in a 1:1:1 ratio. The primary outcome is complete haemostasis of the exposed cancellous bone surface following the prespecified intervention and anatomical-level-specific standardized compression period, without rescue haemostatic intervention during the subsequent standardized 60-second observation period. Secondary outcomes include time to haemostasis, haemostasis grade, rescue haemostasis, blood loss, rebleeding, surgeon-rated ease of application, intervention handling time, postoperative bleeding and wound outcomes.

Bleeding from exposed cancellous bone and marrow spaces is an important but relatively understudied component of haemostasis following bone amputation. Following single-ray amputation, soft-tissue bleeding is controlled using standardized surgical techniques and the study intervention is subsequently evaluated specifically for bleeding originating from the transected cancellous bone surface.

Participants will be randomized in a 1:1:1 ratio to fibrillar Type-I collagen haemostat, conventional bone wax, or standardized compression alone without topical haemostatic material.

The operative sequence will consist of completion of the planned amputation, standardized irrigation, tourniquet release, standardized soft-tissue haemostasis, identification and documentation of cancellous bone bleeding, randomization, application of the allocated intervention, standardized temporary compression, removal of the compression dressing and standardized 60-second haemostasis assessment.

Compression duration will be determined by anatomical level and will be identical across all three randomized treatment groups within each anatomical category: 2 minutes for phalanx, 3 minutes for metacarpal and 5 minutes for metatarsal.

The primary outcome is complete haemostasis of the exposed cancellous bone surface after completion of the applicable anatomical-level-specific compression period and during the subsequent standardized 60-second observation period, without additional haemostatic intervention.

Secondary outcomes include time to haemostasis, haemostasis grade, first-application success, rescue haemostasis, quantitative blood loss, rebleeding, postoperative bleeding, haematoma, wound complications, material utilization and cost. Surgeon-rated ease of application will be assessed immediately after the intervention using a 100-mm visual analogue scale and standardized handling questions.

The study will include adults undergoing planned single-ray amputation involving the phalanx, metacarpal or metatarsal.

Inclusion Criteria:

• Age ≥18 years.
• Planned surgical single-ray amputation involving one or more phalangeal, metacarpal or metatarsal bone segments.
• Presence of an exposed cancellous bone surface following planned bone transection.
• Ability to undergo the standardized operative protocol.
• Ability to provide written informed consent.
• Willingness to comply with postoperative follow-up

Exclusion Criteria:

• Known congenital or acquired bleeding disorder.
• Severe uncorrected coagulopathy.
• Severe thrombocytopenia considered clinically significant by the treating team.
• Active major haemorrhage unrelated to the operative field.
• Requirement for major vascular reconstruction during the procedure.
• Procedures in which standardized assessment of cancellous bone bleeding is impossible.
• Known hypersensitivity to bovine or ovine collagen or to bone wax.
• Previous severe adverse reaction to the study haemostatic materials.
• Simultaneous multiple unrelated amputation procedures where attribution of bleeding cannot be standardized.
• Inability to obtain informed consent.
• Any condition considered by the investigator to make participation unsafe or to compromise the integrity of the trial.