Hyperbaric oxygen therapy is an adjunct to surgical debridement and long-term intravenous antibiotics for chronic refractory osteomyelitis, the persistent bone infection that has failed at least one prior course of appropriate surgical and antibiotic management. HBOT restores the oxygen-dependent neutrophil bactericidal activity that is impaired in chronically hypoxic infected bone, enhances the activity of certain antibiotics (notably aminoglycosides and fluoroquinolones), and supports both osteoclast and osteoblast activity in the bone-remodelling process. Refractory osteomyelitis is recognised by Health Canada as one of the 14 conditions for which provincial health insurance covers HBOT at hospital-based programmes.
Quick Answer
Does HBOT help refractory osteomyelitis? Hyperbaric oxygen therapy is an adjunct to surgical debridement and long-term intravenous antibiotics for chronic refractory osteomyelitis, the persistent bone infection that has failed at least one prior course of appropriate surgical and antibiotic management. HBOT restores the oxygen-dependent neutrophil bactericidal activity that is impaired in chronically hypoxic infected bone, enhances the activity of certain antibiotics (notably aminoglycosides and fluoroquinolones), and supports both osteoclast and osteoblast activity in the bone-remodelling process. Refractory osteomyelitis is recognised by Health Canada as one of the 14 conditions for which provincial health insurance covers HBOT at hospital-based programmes.
Osteomyelitis is bacterial or fungal infection of bone. It becomes "refractory" (the term used in the UHMS Indications volume and Health Canada-aligned Canadian guidelines) when chronic infection persists despite adequate surgical debridement and at least four to six weeks of culture-targeted antibiotics. The Cierny-Mader classification (the standard staging system in orthopaedic infectious-disease practice) identifies four anatomic types and three host classes; refractory osteomyelitis typically involves Stage 3 (localised) or Stage 4 (diffuse) disease in a Class B (compromised) or Class C (severely compromised) host. Around 30 percent of chronic osteomyelitis cases meet refractory criteria after the initial treatment cycle.
The most common Canadian patterns are mandibular osteomyelitis (particularly post-radiation and post-extraction in irradiated jaws), vertebral osteomyelitis with discitis (often hematogenous, sometimes following spinal injection or surgery), sternal and sternoclavicular osteomyelitis (after cardiothoracic surgery or in IV drug users), tibial and femoral osteomyelitis (after trauma or open fracture), calcaneal osteomyelitis (after diabetic foot ulcer), and skull osteomyelitis (after sinusitis, mastoiditis, or neurosurgical procedures). Diabetes mellitus, peripheral vascular disease, prior radiation, immunosuppression, and active smoking are the dominant host risk factors.
The pathophysiology that makes osteomyelitis refractory is the formation of avascular sequestrae (devitalised pieces of dead bone) that harbour persistent infection inaccessible to antibiotics and immune cells, surrounded by hypoxic, fibrotic peri-osseous tissue. The bone becomes a microbiologic refuge where the standard tools of bone-infection management (surgical debridement, IV antibiotics, host optimisation) reach their limit. Adjunctive HBOT is added precisely to address the hypoxic environment that allows the infection to persist.
Hyperbaric oxygen therapy attacks refractory osteomyelitis through five convergent mechanisms.
First, restoration of oxygen-dependent neutrophil killing. The oxidative burst that neutrophils use to kill ingested bacteria requires tissue pO2 above 30 mmHg, but the chronically infected bone bed is profoundly hypoxic, with measured pO2 values often below 5 mmHg. HBOT at 2.0 to 2.5 ATA on 100 percent oxygen raises tissue pO2 to several hundred mmHg during each session, restoring full neutrophil bactericidal function for hours after each treatment.
Second, antibiotic synergy. Aminoglycosides and fluoroquinolones require active oxygen-dependent transport across bacterial membranes for full activity. In hypoxic bone, even when serum drug levels are therapeutic, intra-bacterial drug concentrations are inadequate. HBOT corrects this defect, restoring antibiotic activity in tissue that was previously functionally drug-resistant. Beta-lactam activity is also potentiated indirectly through the oxygen-dependent metabolic state of the bacteria.
Third, suppression of anaerobes. Many chronic osteomyelitis infections involve anaerobic or microaerophilic organisms (Bacteroides, Fusobacterium, Propionibacterium, anaerobic streptococci) whose growth is inhibited at the elevated tissue oxygen tensions HBOT delivers.
Fourth, support for osteoclast activity. Healthy bone-remodelling requires osteoclast-mediated removal of devitalised sequestrae. Osteoclast function is oxygen-dependent and is impaired in hypoxic infected bone. HBOT restores the metabolic environment for osteoclast activity, allowing the bone-remodelling machinery to clear the dead bone that is harbouring the infection.
Fifth, support for osteoblast and angiogenic activity. New blood-vessel growth at the infected bone site (the same VEGF-mediated angiogenesis that underpins HBOT's effect in radiation injury and chronic wounds) restores vascularity to the previously avascular tissue, re-establishing the oxygen and antibiotic delivery that allows definitive healing. Marx-style histology series in irradiated bone, and parallel work in non-irradiated chronic osteomyelitis, demonstrate measurable increases in capillary density after a 20- to 30-session course.
Typical Treatment Protocol
The standard adjunctive protocol is 2.0 to 2.5 ATA on 100 percent oxygen for 90 minutes per session, delivered five days per week. Total course is typically 20 to 40 sessions over four to eight weeks, paralleled with culture-targeted IV antibiotic therapy and serial surgical debridement as needed. The course is sometimes extended to 60 sessions for severe or extensive disease, particularly mandibular osteomyelitis where the response can be slow but durable. The sequence is: surgical debridement of grossly infected and devitalised bone first, culture-targeted IV antibiotics second (typically four to six weeks of an appropriate parenteral agent), HBOT third, with HBOT continuing through the antibiotic course and beyond if response is incomplete. For surgically inaccessible disease (deep vertebral osteomyelitis with discitis, for example), HBOT is added without primary surgical debridement, with the recognition that response may be slower in the absence of source-control. Most Canadian programmes deliver HBOT in the outpatient setting after the patient is medically stable; some critically ill or immobilised patients receive it as inpatients.
Level B - Moderate Evidence
Supported by controlled studies and clinical evidence
HBOT combined with surgical debridement and culture-targeted IV antibiotics achieves clinical and radiographic healing in approximately 80 to 85 percent of refractory osteomyelitis cases in published case series, including those of Davis 1986 and Mader 1990, with substantially lower recurrence rates compared to standard surgery and antibiotics alone.
A Cochrane Review of HBOT for chronic osteomyelitis is in development; existing systematic reviews including Goldman 2009 and others conclude that adjunctive HBOT is associated with improved outcomes in refractory cases, with the strongest signal in mandibular and post-radiation osteomyelitis.
HBOT restores oxygen-dependent neutrophil bactericidal activity in tissue oxygen tensions only reachable at 2.0 ATA and above. Normobaric oxygen alone does not achieve this in hypoxic infected bone.
Aminoglycoside and fluoroquinolone antibiotic activity is potentiated by HBOT through restoration of oxygen-dependent intra-bacterial drug accumulation, particularly relevant in chronic osteomyelitis where standard tissue drug concentrations may be sub-therapeutic at the bone-infection interface.
The standard adjunctive protocol is 2.0 to 2.5 ATA, 90 minutes per session, once daily for 20 to 40 total sessions, occasionally extended to 60. Mandibular osteomyelitis often follows a Marx-style 30-and-10 sequence (30 sessions, surgery, 10 more sessions) when extensive debridement is planned.
HBOT supports both osteoclast activity (controlled removal of devitalised bone) and osteoblast and angiogenic activity (new bone formation and re-vascularisation), the bone-remodelling machinery that is impaired in chronically hypoxic infected bone.
Highest-evidence-tier studies tagged to this condition in the Canada Hyperbarics research database, ranked by evidence tier (1 = meta-analysis or RCT, 2 = cohort, 3 = case series), most recent first.
Undersea Hyperb Med · 2021 · Review
Eur Arch Otorhinolaryngol · 2026 · Study
Undersea & hyperbaric medicine : journal of the Undersea and Hyperbaric Medical Society, Inc · 2025 · RCT
J Stomatol Oral Maxillofac Surg · 2025 · Case Report
Most patients are referred to a hospital hyperbaric programme by their orthopaedic surgeon, infectious-disease physician, dental surgeon (for mandibular cases), or wound-care specialist after the diagnosis is confirmed (typically on MRI, CT, or bone biopsy with culture) and at least one cycle of surgery and antibiotics has failed to eradicate the infection. The hyperbaric medicine team confirms the diagnosis and the refractory status, reviews imaging and microbiology, screens for absolute and relative contraindications, and books the treatment course.
Daily sessions typically begin within one to four weeks of consultation. The course is long: 20 to 40 sessions over four to eight weeks, sometimes extended to 60 sessions, paralleled with the IV antibiotic course. You change into cotton scrubs (no synthetic fabrics, no skin lotions, no jewellery), enter the chamber, and lie down (in a monoplace chamber) or sit in a recliner (in a multiplace chamber with multiple patients). Pressurisation takes five to ten minutes and feels like the descent in an aircraft. During the 90-minute treatment phase you breathe pure oxygen, often through a hood or mask. Decompression takes another five to ten minutes.
Response is measured by clinical resolution of pain, drainage, and systemic signs of infection; by serial inflammatory markers (CRP, ESR); and by serial imaging where appropriate. Most responders show measurable improvement by sessions 15 to 20. The orthopaedic, infectious-disease, and hyperbaric teams coordinate ongoing surgical decisions (further debridement, hardware removal, soft-tissue coverage) throughout the course. Recovery from refractory osteomyelitis is typically prolonged, with rehabilitation needs (mobilisation, weight-bearing protocols, dental rehabilitation for mandibular cases) extending beyond the acute treatment phase.
Refractory osteomyelitis is recognised by Health Canada as one of the 14 conditions for which hyperbaric oxygen is the established standard of adjunctive care. Treatment is delivered at the 11 hospital-based hyperbaric programmes across seven provinces under provincial health insurance.
In Ontario, OHIP covers treatment at the three hospital programmes (Toronto General / UHN, Hamilton General Hospital, The Ottawa Hospital). Select eligible Independent Health Facilities may also bill OHIP for approved indications, with eligibility varying by facility and indication. Confirm directly with the IHF before booking. In Alberta, both Misericordia Edmonton (Covenant Health) and the Foothills Medical Centre / AJECCC Calgary (Alberta Health Services) accept refractory-osteomyelitis referrals, with the Alberta hospital billing code 13.99I (per 15 minutes). British Columbia (MSP) covers treatment at Vancouver General Hospital. RAMQ covers treatment at Hôpital du Sacré-Cœur de Montréal and Hôtel-Dieu de Lévis in Quebec. MSI (Nova Scotia), MCP (Newfoundland and Labrador), and Saskatchewan also cover their respective hospital programmes.
For patients in provinces or territories without an in-province hospital programme (Manitoba, New Brunswick, Prince Edward Island, Yukon, Northwest Territories, Nunavut), publicly funded HBOT is accessed through inter-provincial referral coordinated by the orthopaedic surgeon, infectious-disease physician, or family doctor. Inter-provincial billing arrangements typically cover the medically necessary treatment cost; travel and accommodation for the four to eight weeks of daily sessions are usually the patient's responsibility unless the home province operates a medical-travel assistance programme.
Hyperbaric oxygen therapy for the 14 Health Canada-recognised conditions, including Refractory Osteomyelitis, is delivered at the 11 hospital hyperbaric programmes located in seven provinces (Ontario, Quebec, British Columbia, Alberta, Nova Scotia, Newfoundland and Labrador, and Saskatchewan). The six provinces and territories without an in-province hospital programme (Manitoba, New Brunswick, Prince Edward Island, Yukon, Northwest Territories, and Nunavut) route patients to the nearest receiving hospital programme. Use the links below for province-specific coverage, referral pathway, and emergency routing details.
Hospital + Private
OHIP (Ontario Health Insurance Plan)
Hospital Only
MSP (Medical Services Plan)
Hospital + Private
Alberta Health / AHCIP
Hospital Only
RAMQ
Disrupted
Saskatchewan Health Authority
No Hospital Chamber
Manitoba Health
Hospital Only
MSI (Medical Services Insurance)
No Hospital Chamber
Medicare NB
Hospital Only
MCP (Medical Care Plan)
Out-of-Province Referral
Health PEI
Out-of-Province Referral
Yukon Health and Social Services
Out-of-Province Referral
NWT Health and Social Services
Out-of-Province Referral
Nunavut Department of Health
For acute or emergency presentations of Refractory Osteomyelitis, call 911 first. The receiving emergency department coordinates urgent transfer to the nearest hospital hyperbaric programme through the relevant provincial transfer network (CritiCall Ontario at 1-800-668-4357, BC Patient Transfer Network, EHS Nova Scotia, or equivalent). For diving-related emergencies, the Divers Alert Network (DAN) emergency hotline is 1-919-684-9111.
Untreated pneumothorax is the only absolute contraindication, because trapped intrathoracic air expands on decompression. Concurrent treatment with bleomycin (oxygen-induced pulmonary fibrosis risk) and disulfiram (interference with antioxidant defences) are also contraindicated. Relative contraindications, weighed against expected benefit on a per-patient basis, include severe chronic obstructive pulmonary disease with bullous lung disease, uncontrolled seizure disorder, claustrophobia (manageable in monoplace chambers and with behavioural strategies), recent middle-ear or sinus surgery, and uncontrolled hypertension. The four-to-eight-week treatment course is itself a practical barrier for patients in remote areas, who may need to relocate temporarily near the hospital programme; provincial medical-travel assistance programmes can defray some of this cost where available. Hardware in the infected bone (orthopaedic plates, intramedullary nails, joint prostheses) is not a contraindication to HBOT, but it does affect the broader management strategy. The orthopaedic and infectious-disease teams may decide that hardware removal is required for definitive eradication; HBOT can be continued through this surgical sequence.
Osteomyelitis is considered refractory when it persists despite adequate surgical debridement and at least four to six weeks of culture-targeted antibiotic therapy. Chronic infections with devascularised dead bone (sequestrae) and a compromised host (diabetes, peripheral vascular disease, prior radiation, immunosuppression) are the most common pattern. Approximately 30 percent of chronic osteomyelitis cases meet refractory criteria after the initial treatment cycle.
Typically 20 to 40 daily sessions over four to eight weeks, sometimes extended to 60 sessions for severe or extensive disease, combined with ongoing culture-targeted IV antibiotic therapy and serial surgical debridement as needed. The treatment course is longer than for most other HBOT indications. Mandibular osteomyelitis often follows a Marx-style 30-and-10 sequence.
No. HBOT is an adjunct to surgical debridement and culture-targeted IV antibiotics, not a replacement. The sequence is debride first, antibiotics second, HBOT third, with HBOT continuing through the antibiotic course. Surgery provides source-control by removing devitalised infected bone; antibiotics target the residual organism load; HBOT addresses the hypoxic environment that allowed the infection to persist.
Yes. Refractory osteomyelitis is recognised by Health Canada and covered at the 11 hospital-based hyperbaric programmes under OHIP, MSP, AHCIP, RAMQ, MSI, MCP, and Saskatchewan Health. Select eligible Independent Health Facilities in Ontario may also bill OHIP for approved indications. Private clinic treatment is typically self-pay.
Yes. Mandibular osteomyelitis, particularly when complicated by prior radiation, is one of the strongest indications for adjunctive HBOT. The Marx 30-and-10 protocol (30 sessions before planned debridement and 10 sessions afterward) is the standard regimen and remains the foundation of mandibular HBOT practice today. Earlier referral, before the disease becomes extensive, generally produces better outcomes.
Not necessarily. Hardware (orthopaedic plates, intramedullary nails, joint prostheses) does not preclude HBOT, but the orthopaedic and infectious-disease teams may decide that hardware removal is needed for definitive eradication of infection. HBOT can be continued through this surgical sequence. The decision is made on a per-patient basis.
There is no acute time-window comparable to emergency indications. The course is typically scheduled within one to four weeks of consultation, after the initial surgery and antibiotic plan are established. The decision to add HBOT is made jointly by orthopaedic surgery, infectious-disease, and hyperbaric medicine.
Typical course for vertebral osteomyelitis with discitis is 30 to 40 sessions at 2.0 to 2.5 ATA on 100 percent oxygen for 90 minutes per session, paralleled with the standard six-week IV antibiotic course. The course can be extended for residual infection or persistent imaging findings. Surgical fixation, when indicated, is integrated into the management plan with the orthopaedic spine team.
In most cases, no. Surgical debridement of devitalised infected bone is the foundation of treatment. There are limited situations (surgically inaccessible deep vertebral osteomyelitis, for example, or patient unfit for surgery) where HBOT plus prolonged IV antibiotics is the primary strategy, but response is slower and recurrence rates are higher than when surgery is part of the plan.
You change into cotton scrubs, enter the chamber, and lie down (in a monoplace) or sit in a recliner (in a multiplace with multiple patients). Pressurisation takes five to ten minutes and feels like the descent in an aircraft. Most people clear their ears with the same technique used in flying. During the 90-minute treatment phase you breathe pure oxygen, often through a hood or mask, while reading, watching a screen, or sleeping. Decompression takes another five to ten minutes. The most common sensation during a session is a feeling of warmth.
The most common side effect is ear barotrauma during pressurisation, managed with pressure-equalisation techniques and resolving between sessions. Other relatively common effects are temporary near-sightedness during the course (vision usually returns to baseline within a few weeks of stopping), fatigue, and rare confinement anxiety. Serious complications including pneumothorax, oxygen toxicity seizures, and cardiac decompensation are uncommon at the standard 2.0 to 2.5 ATA pressures used for refractory osteomyelitis.
Speak with your orthopaedic surgeon, infectious-disease physician, dental surgeon (for mandibular cases), or family physician. They will document the failed prior course of surgery and antibiotics, confirm the diagnosis with imaging and microbiology, and refer you to the nearest hospital hyperbaric programme. The receiving programme typically schedules a consultation within two to four weeks, with treatment beginning shortly after if you meet eligibility criteria.
The Canada Hyperbarics verified directory at canadahyperbarics.ca/facilities/ lists all 11 hospital programmes alongside their phone numbers, websites, and current chamber status. Coverage details for every province are at canadahyperbarics.ca/hbot-coverage-canada/.