Regional CBF in chronic stable TBI treated with hyperbaric oxygen.

To investigate whether Hyperbaric Oxygen Therapy (HBO2) could improve neurologic deficits and regional cerebral blood flow (rCBF) in chronic traumatic brain injuries (TBI), the authors employed a nonrandomized control pilot trial. Five subjects, at least three years post head injury, received HBO2. Five head injured controls (HIC) were matched for age, sex, and type of injury. Five healthy subjects served as normal controls. Sixty-eight normal volunteers comprised a reference data bank against which to compare SPECT brain scans. HBO2 subjects received 120 HBO2 in blocks of 80 and 40 treatments with an interval five-month break. Normal controls underwent a single SPECT brain scan, HBO2, and repeat SPECT battery. TBI subjects were evaluated by neurologic, neuropsychometric, exercise testing, and pre and post study MRIs, or CT scans if MRI was contraindicated. Statistical Parametric Mapping was applied to SPECT scans for rCBF analysis. There were no significant objective changes in neurologic, neuropsychometric, exercise testing, MRIs, or rCBF. In this small pilot study, HBO2 did not effect clinical or regional cerebral blood flow improvement in TBI subjects.

The role and effectiveness of adjunctive hyperbaric oxygen therapy in the management of musculoskeletal disorders.

The management of musculoskeletal disorders is an increasing challenge to clinicians. Successful treatment relies on a wide range of multidisciplinary interventions. Adjunctive hyperbaric oxygen (HBO) therapy has been used as an orthopaedic treatment for several decades. Positive outcomes have been reported by many authors for orthopaedic infections, wound healing, delayed union and non-union of fractures, acute traumatic ischemia of the extremities, compromised grafts, and burn injuries. Severe side effects have also been reported with this therapy. To aid in the use of HBO therapy in orthopaedics, we reviewed 43 papers published in the past four decades and summarised the mechanisms, effectiveness, indications and contraindications, side effects, and cost impact of adjunctive hyperbaric oxygen therapy in the management of difficult musculoskeletal disorders. Adjunctive HBO therapy is an effective treatment modality for the management of some severe and refractory musculoskeletal problems. If appropriate candidates are carefully identified, hyperbaric oxygen is a limb- and sometimes life-saving therapy. HBO therapy significantly reduces the length of the patient's hospital stay, amputation rate, and wound care expenses. Thus, it is a cost-effective modality. A clinician must understand the side effects and risks of HBO treatment. Close monitoring throughout the treatment is warranted to minimise the risk to the patients.

Mycobacterium tuberculosis and Mycobacterium fortuitum osteomyelitis of the foot and septic arthritis of the ankle in an immunocompetent patient.

Mycobacteria, both tuberculous and nontuberculous, are recognized as a cause of chronic bone and joint infection. However, the diagnosis of mycobacterial infection is easily missed because of the absence of systemic involvement. Moreover, specific microbiologic techniques are required to detect mycobacteria in clinical specimens. Infections due to uncommon pathogens such as mycobacteria are more likely to occur in the immunocompromised host. A case of septic arthritis of the ankle and osteomyelitis of the foot due to both tuberculous and nontuberculous mycobacteria in an immunocompetent host is reported here.

Comparative evaluation of oral levofloxacin and parenteral nafcillin in the treatment of experimental methicillin-susceptible Staphylococcus aureus osteomyelitis in rabbits.

Methicillin-susceptible Staphylococcus aureus (MSSA) is the most common pathogen recovered from osteomyelitis patients. The current standard therapeutic method for acute phase osteomyelitis is parenteral antibiotic therapy. However, parenteral administration has negative aspects, such as secondary infection, patient inconvenience and high cost. The use of single oral antibiotic therapy may alleviate these problems. Therefore, the purpose of this study was to compare the effectiveness of standard once per day dosing of oral levofloxacin with a standard parenteral antibiotic regimen (nafcillin four times daily) for the treatment of experimental MSSA osteomyelitis in rabbits. Nearly all tibias from untreated infected controls (n = 27) revealed positive cultures (93%) for S. aureus, while the levofloxacin-treated group (n = 20) demonstrated significantly lower percentages of S. aureus infection (50%). The infected tibias of the nafcillin-treated group (n = 20) demonstrated significantly lower percentages (10%) of infected tibias than either the controls or the levofloxacin-treated groups (P < 0.05). The inferior efficacy of levofloxacin may have been due to the pharmacokinetic profile of this fluoroquinolone. The serum kinetics demonstrated that following single dose administration, levofloxacin was almost undetectable after 12 h. Studies in which levofloxacin is dosed every 12 h or given at increased doses in order to obtain bactericidal concentrations throughout the treatment regimen are needed.

Hematogenous pyogenic facet joint infection.

STUDY DESIGN: Retrospective. OBJECTIVES: To determine the incidence, clinical presentation, diagnostic laboratory values, imaging characteristics, and optimal treatment of hematogenous pyogenic facet joint infections. SUMMARY OF BACKGROUND DATA: There are 27 documented cases of hematogenous pyogenic facet joint infections. Data regarding incidence, clinical presentation, diagnosis, and treatment response are incomplete because of the paucity of reported cases. METHODS: This is a retrospective study of all cases of hematogenous pyogenic facet joint infection treated at one institution. Data from previous publications were combined with the present series to identify pertinent clinical characteristics and response to treatment. RESULTS: A total of six cases (4%) of hematogenous pyogenic facet joint infection were identified of 140 cases of hematogenous pyogenic spinal infection at our institution. Combining all reported cases reveals the following: The average patient age is 55 years. Ninety-seven percent of cases occur in the lumbar spine. Epidural abscess formation complicates 25% of the cases of which 38% develop severe neurologic deficit. Erythrocyte sedimentation rate and C-reactive protein are elevated in all cases. Staphylococcus aureus is the most common infecting organism. Magnetic resonance imaging is accurate in identifying the septic joint and associated abscess formation. Percutaneous drainage of the involved joint has a higher rate of success (85%) than treatment with antibiotics alone (71%), but the difference is not significant (P = 0.37). CONCLUSIONS: Hematogenous pyogenic facet joint infection is a rare but underdiagnosed clinical entity. Facet joint infections may be complicated by abscess formation in the epidural space or in the paraspinal muscles. Uncomplicated cases treated with percutaneous drainage and antibiotics may fare better than those treated with antibiotics alone. Cases complicated by an epidural abscess and severe neurologic deficit should undergo immediate decompressive laminectomy.

Hematogenous pyogenic spinal infections and their surgical management.

STUDY DESIGN: Mainly a retrospective study of 101 cases of pyogenic spinal infection, excluding postoperative infections. Data were obtained through medical record review, imaging examination, and patient follow-up evaluation. SUMMARY OF BACKGROUND DATA: Hematogenous pyogenic spinal infection has been described variously as spondylodiscitis, discitis, vertebral osteomyelitis, and epidural abscess. Recommended treatment options have included conservative methods (antibiotics and bracing) and surgical intervention. However, a comprehensive classification that would aid in diagnosis, treatment planning, and prognosis has not yet been devised. OBJECTIVES: To analyze the bacteriology, pathologic entities, complications, and results of treatment options for pyogenic spinal infection. METHOD: All patients received plain radiographs, gadolinium-enhanced magnetic resonance imaging scans, and bone/gallium radionuclide studies. All patients had tissue biopsies. Bacteriology, hematology, and predisposing factors were analyzed. All patients received intravenous and oral antibiotics. A total of 58 patients underwent surgery. Patient outcomes were correlated with clinical status, with treatment method and, where applicable, with location and nature of epidural compression. Statistical analyses were performed. RESULTS: Spondylodiscitis occurred most commonly with primary epidural abscess, spondylitis, discitis, and pyogenic facet arthropathy, all occurring rarely. Staphylococcus aureus was the main organism. Infection elsewhere was the most common predisposing factor. Leukocyte counts were elevated in 42.6% of spondylodiscitis cases. The erythrocyte sedimentation rate was elevated in all cases of epidural abscess. There were 35 cases of epidural abscess (frank abscess, 29; granulation tissue, 6). Epidural abscess complicating spondylodiscitis occurred most often in the cervical spine, followed by thoracic and lumbar areas. The rate of paraplegia or paraparesis also was highest in cervical and thoracic regions. There were no cases of quadriplegia. All patients with either epidural granulation tissue or paraparesis recovered completely after surgical decompression. Only 18% of patients with frank epidural abscess and 23% of patients with paralysis recovered completely after surgical decompression. Patients with spondylodiscitis who were treated nonsurgically reported residual back pain more often (64%) than patients treated surgically (26.3%). CONCLUSIONS: Pyogenic spinal infection can be thought of as a spectrum of disease comprising spondylitis, discitis, spondylodiscitis, pyogenic facet arthropathy, and epidural abscess. Spondylodiscitis is more prone to develop epidural abscesses in the cervical spine (90%) than the thoracic (33.3%) or lumbar (23.6%) areas. Thecal sac neurocompression has a greater chance of causing neurologic deficit in the thoracic spine (81.8%). Treatment of neurologic deficit caused by epidural abscess is prompt surgical decompression, with or without fusion. Patients with frank abscess had less favorable outcomes than those with granulation tissue, and paraplegia responded to treatment more poorly than paraparesis. Surgery was preferable to nonsurgical treatment for improving back pain.

Bone and joint infections in the elderly: practical treatment guidelines.

Two types of haematogenous osteomyelitis that are seen in the elderly are vertebral and long bone osteomyelitis. Osteomyelitis secondary to contiguous foci of infection can occur in older adults without vascular insufficiency (secondary to pressure ulcers) or with vascular insufficiency due to diabetes mellitus or peripheral vascular disease from atherosclerosis. Most cases of osteomyelitis can be reasonably treated with adequate drainage, thorough debridement, obliteration of dead space, wound protection, and antimicrobial therapy. Patients are initially given a broad spectrum antimicrobial that is changed to specific antimicrobial therapy based on meticulous bone cultures taken at debridement surgery or from deep bone biopsies. Surgical management is often required in the treatment of osteomyelitis and includes adequate drainage, extensive debridement of all necrotic tissue, obliteration of dead spaces, stabilisation, adequate soft tissue coverage, and restoration of an effective blood supply. Bone repair and bone mineral density may be significantly retarded and may be corrected by eliminating risk factors, supplementing the diet with calcium, bisphosphonates, and/or vitamin D, and treating with testosterone and/or estrogen when deficient. Sodium fluoride treatment and anabolic steroids may be used as alternatives. Septic arthritis is a medical emergency, and prompt recognition and rapid and aggressive treatment are critical to ensuring a good prognosis. The treatment of septic arthritis includes appropriate antimicrobial therapy and joint drainage. Adverse effects of prescribed antibacterials occur more often in the elderly patient than in young adults. The physician can help to minimise the incidence of adverse effects and improve outcomes by being aware of the principles of clinical pharmacology, the characteristics of specific drugs, and the special physical, psychological and social needs of older patients.

Adult posttraumatic osteomyelitis of the tibia.

Posttraumatic tibial osteomyelitis results from trauma or nosocomial infection from the treatment of trauma that allows organisms to enter bone, proliferate in traumatized tissue, and cause subsequent bone infection. The resulting infection is usually polymicrobial. The patient may be classified using the May and the Cierny-Mader classification systems. The diagnosis is based on the isolation of the pathogen(s) from the bone, or blood cultures. Appropriate therapy of posttraumatic tibial osteomyelitis includes adequate drainage, thorough debridement, obliteration of dead space, stabilization when necessary, wound protection, and specific antimicrobial therapy.

Antimicrobial treatment of chronic osteomyelitis.

Chronic osteomyelitis has been a difficult problem for patients and the treating physicians. Appropriate antibiotic therapy is necessary to arrest osteomyelitis along with adequate surgical therapy. Factors involved in choosing the appropriate antibiotic(s) include infection type, infecting organism, sensitivity results, host factors, and antibiotic characteristics. Initially, antibiotics are chosen on the basis of the organisms that are suspected to be causing the infection. Once the infecting organism(s) is isolated and sensitivities are established, the initial antibiotic(s) may be modified. In selecting specific antibiotics for the treatment of osteomyelitis, the type of infection, current hospital sensitivity resistance patterns, and the risk of adverse reactions must be strongly appraised. Antibiotic classes used in the treatment of osteomyelitis include penicillins, beta-lactamase inhibitors, cephalosporins, other beta-lactams (aztreonam and imipenem), vancomycin, clindamycin, rifampin, aminoglycosides, fluoroquinolones, trimethoprim-sulfamethoxazole, metronidazole, and new investigational agents including teicoplanin, quinupristin/dalfopristin, and oxazolidinones. Traditional treatments have used operative procedures followed by 4 to 6 weeks of parenteral antibiotics. Adjunctive therapy for treating chronic osteomyelitis may be achieved by using beads, spacers, or coated implants to deliver local antibiotic therapy and/or by using hyperbaric oxygen therapy (once per day for 90-120 minutes at two to three atmospheres at 100% oxygen).

Oral rifampin plus azithromycin or clarithromycin to treat osteomyelitis in rabbits.

A rabbit model for Staphylococcus aureus osteomyelitis was used to compare 28-day combination antibiotic therapy using oral rifampin (40 mg/kg, twice daily) plus oral azithromycin (50 mg/kg, once per day), oral clarithromycin (80 mg/kg, twice daily), or parenteral nafcillin (30 mg/kg, four times daily). The left tibial metaphysis of New Zealand White rabbits was infected with Staphylococcus aureus. Grades 3 to 4 osteomyelitis (according to the Cierny-Mader classification system) development in the rabbits was confirmed radiographically. After antibiotic therapy regimens of 28 days, all tibias from controls that were infected but left untreated (n = 10) revealed positive cultures for Staphylococcus aureus at a mean concentration of 2.8 x 10(4) colony forming units/g bone. The rifampin plus clarithromycin (n = 15) and rifampin plus azithromycin (n = 15) groups showed significantly lower percentages of positive Staphylococcus aureus infection (20% and 13.3%, respectively) and bacterial concentrations (3.5 x 10(1) and 1.75 x 10(1) colony forming units/g bone, respectively). The osteomyelitic tibias of the nafcillin plus rifampin treated group (n = 7) showed no detectable Staphylococcus aureus infection (significantly lower than controls). The differences observed for bone bacterial concentrations and sterilization percentages between the antibiotic treated groups were not statistically significant. Although fluoroquinolones (including ofloxacin and ciprofloxacin) are the agents usually prescribed with rifampin, increasing resistance has been observed. Although macrolides traditionally are not used in the treatment of osteomyelitis, the results of this study indicate that azithromycin and clarithromycin may be attractive partners for rifampin for the treatment of Staphylococcus aureus osteomyelitis in humans.

The host and the skeletal infection: classification and pathogenesis of acute bacterial bone and joint sepsis.

Bone and joints are normally sterile areas. Bacteria may reach these sites by either haematogenous spread or spread from an exogenous or endogenous contiguous focus of infection. Bone infection, or osteomyelitis, is characterized by a progressive infectious process resulting in inflammatory destruction of bone, bone necrosis and new bone formation. Joint infections, or infectious arthritis, arise either from the haematogenous spread of organisms through the highly vascularized synovial membrane or from direct extension of a contiguous bone or soft tissue infection. The most commonly involved joints are the knee and the hip, although any joint can become infected. Infectious arthritis is monoarticular in 90% of cases. Some of the questions to be answered in this chapter include: how bacteria reach and cause damage in the bones and joints; what the current classification systems of bone and joint infections are; what some risk factors and host factors associated with bone and joint infection are; what some current characteristics of musculoskeletal infections are and whether the damage to joints can be diminished by treatment.

Blastomycosis of the lumbar spine: case report and review of the literature, with emphasis on diagnostic laboratory tools and management.

We report on the conservative and surgical management of a patient with blastomycosis of the lumbar spine, causing severe and crippling deformity. The diagnosis was made through biopsy. Curative removal, reconstruction and realignment of the spine were achieved. Imaging modalities were highlighted, with a detailed discussion of the histology and conservative and surgical management. We emphasize the importance of early, aggressive treatment of blastomycosis to prevent deformity and disability, and to enable identification of the best management of a destructive lesion with deformity. This case demonstrates that empirical treatment should not be used in cases of unusual sinus and abscess locations. Specific diagnosis and early treatment are indicated to prevent dreadful complications and spinal deformity resulting from blastomycosis. Aggressive antifungal therapy can cure the disease but does not control complications related to deformity. The latter can only be addressed by surgical reconstruction. We review the literature of surgical treatment, focusing on abscess drainage, bone fusion and posterior instrumentation in the absence of addressing the deformity component.

Short-term tympanostomy in conjunction with hyperbaric oxygen therapy.

OBJECTIVE: To determine the most effective method of short-term middle ear aeration in patients unable to tolerate hyperbaric oxygen (HBO) therapy. STUDY DESIGN: Prospective study comparing two methods of short-term tympanostomy in each patient. METHODS: Seventeen adult patients were referred for management of barotitis and inability to tolerate hyperbaric oxygen therapy (HBO). Each patient underwent CO2 laser tympanostomy on the right ear and tympanostomy with T-tube placement in the left ear. The tube was removed on completion of HBO. Patients were asked to rate pain and their satisfaction with each method of tympanostomy using a visual analog scale. Otorrhea, persistent perforation, recurrent barotitis, hearing loss, and otalgia occurring during the study period were documented. RESULTS: Laser tympanostomy was associated with a significantly lower incidence of otorrhea but was attended by recurrent barotitis in four of 16 patients. Laser tympanostomy was perceived as being less painful and was rated higher in overall satisfaction. CONCLUSIONS: Laser tympanostomy is an effective method for management of barotitis in patients unable to tolerate HBO. Otorrhea is significantly reduced, although a risk of recurrent barotitis exists if the laser perforation closes prior to completion of HBO. Both methods of short-term tympanostomy reduce complications when compared with a retrospective cohort.

The effectiveness of gallium citrate Ga 67 radionuclide imaging in vertebral osteomyelitis revisited.

We investigated the role of gallium citrate Ga 67 scanning in diagnosing spondylodiscitis. Scans of 41 patients with suspected spondylodiscitis showed increased radionuclide uptake in 39 patients; these findings correlated with those of magnetic resonance imaging and were proved by biopsy. Two patients with negative findings on gallium scans had been strongly suspected of having spondylodiscitis; biopsy findings in these patients showed degenerative changes. Thirteen patients had negative cultures, while 22 had polygenic infections and 4 had granulomatous infections. Gallium scanning proved to be 100% sensitive, specific, and accurate. The interrater accuracy was excellent. Follow-up scans were used to track therapeutic progress. We recommend complementary bone and gallium scans in cases of suspected spinal infections. If the scan is positive, a biopsy should be done. If the scans are negative, no further investigation is needed.

Percutaneous transpedicular discectomy and drainage in pyogenic spondylodiscitis.

Spondylodiscitis normally heals itself, but it can cause bone destruction leading to deformity and often pain. Debridement of these infections by percutaneous transpedicular discectomy with access from adjacent caudal pedicles can accelerate natural healing and prevent progression to bone destruction and deformity. We outline this technique and discuss a series of 28 patients treated using a percutaneous transpedicular approach to obtain culture and histopathology specimens, permit drainage and antibiotic irrigation, and provide a channel for granulation tissue to invade the infected space. This procedure is safe and effective, but it is contraindicated for epidural abscess or granulation tissue-induced neurocompression and it is ineffective against extensive bone destruction.

Complications of tympanostomy tubes inserted for facilitation of hyperbaric oxygen therapy.

OBJECTIVE: To document the incidence of complications occurring secondary to placement of tympanostomy tubes in patients undergoing hyperbaric oxygen therapy. DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: Forty-five patients referred to the Department of Otolaryngology for inability to tolerate hyperbaric oxygen therapy between January 1, 1990, and December 31, 1995. INTERVENTIONS: All patients underwent bilateral myringotomy and tube placement. OUTCOME MEASURES: Charts were reviewed for complications of tube placement, including otorrhea, otalgia, hearing loss, persistent perforations, and tinnitus. RESULTS: Seventeen (38%) of 45 patients experienced complications, with most having more than 1. Most complications occurred after conclusion of hyperbaric oxygen therapy. Otorrhea was most common, occurring in 13 patients (29%). Persistent tympanic membrane perforations occurred in 7 patients (16%). CONCLUSIONS: The rate of complications is higher than reported for placement of tympanostomy tubes in other patient populations. Coexisting illness, such as diabetes mellitus, may contribute to the development of complications in patients undergoing hyperbaric oxygen therapy. Alternative methods of tympanostomy, with emphasis on shorter duration of intubation, should be considered in this patient population.

Calcaneal osteomyelitis caused by nail puncture wounds.

Plantar puncture wounds to the foot are a common injury. A small number (1.8%) of these puncture wounds become infected and progress to osteomyelitis. The purpose of this article is to report the cases of six patients who developed osteomyelitis of the calcaneus after a puncture wound to the heel caused by a nail. The characteristics of the patients, the pathogenic organism, and the outcome were studied. Patients who were healthy and had no systemic illness (N = 4) had only one pathogenic organism cultured, whereas patients who had systemic illness (diabetes mellitus, N = 2) had more than one pathogenic organism cultured. The only amputation in this group occurred in a patient with diabetes mellitus. It was concluded that diabetic patients who develop calcaneal osteomyelitis from a nail puncture wound are more likely to have multiple pathogens cultured. Furthermore, if a diabetic neuropathy is also present, the nail puncture wound may be the initial injury leading to a chronic ulceration, increasing the risk of amputation.

Treatment of osteomyelitis with a biodegradable antibiotic implant.

A biodegradable antibiotic implant was developed and evaluated in a localized osteomyelitic rabbit model. The biodegradable antibiotic implant was made of polylactic acid and poly(DL-lactide):co-glycolide combined with vancomycin. Localized rabbit tibial osteomyelitis was developed with Staphylococcus aureus. Infected rabbits were divided into eight groups, depending on treatment with or without debridement, systemic antibiotics, or biodegradable beads. After 4 weeks of therapy, the radiographs were obtained of the involved bones, which also were cultured for concentrations of Staphylococcus aureus per gram of bone. Treatment with antibiotic containing polylactic acid and poly(DL-lactide):co-glycolide beads, with and without systemic vancomycin, resulted in bone colony forming unit levels of 10(2.93) and 10(2.84) colony forming units per gram bone, respectively. These bacterial concentrations were approximately 100 times lower than those observed for all other treatment groups. A biodegradable antibiotic bead may provide extended bactericidal concentrations of antibiotics for the time needed to completely treat the particular orthopaedic infection and does not require the surgery needed to remove the polymethylmethacrylate beads.

A practical guide to the diagnosis and management of bone and joint infections.

Infectious arthritis arises from haematogenous spread of organisms through the synovial membrane or from the direct extension of a contiguous infection. The diagnosis rests on the isolation of the pathogen(s) from joint fluid obtained by aspiration or from debridement. Synovial fluid analysis and Gram stains provide clues to the aetiology. The treatment of septic arthritis includes appropriate antimicrobial therapy and joint drainage. Bone infections are currently classified by the Waldvogel or Cierny-Mader classification. Cierny-Mader staging allows stratification and development of comprehensive treatment guidelines for each stage. Osteomyelitis therapy emphasises early diagnosis and aggressive treatment. Radiographs and bone cultures are the mainstays of diagnosis. Radionuclide scans, computerised tomography or magnetic resonance imaging may be obtained when the diagnosis of osteomyelitis is equivocal or to help gauge the extent of the infection. Medical therapy includes improving any host deficiencies, initial antibiotic selection and antibiotic modification based on culture results. Surgical treatment involves debridement of necrotic bone and tissue, obtaining appropriate cultures, managing dead space and, when necessary, obtaining bone stability.

In vitro evaluation of antibiotic diffusion from antibiotic-impregnated biodegradable beads and polymethylmethacrylate beads.

Antibiotic-impregnated beads are used in the dead bone space following debridement surgery to deliver local, high concentrations of antibiotics. Polymethylmethacrylate (PMMA), 2,000-molecular-weight (MW) polylactic acid (PLA), Poly(DL-lactide)-coglycolide (PL:CG; 90:10, 80:20, and 70:30), and the combination 2,000-MW PLA-70:20 PL:CG were individually mixed with clindamycin, tobramycin, or vancomycin. Beads were placed in 1 ml of phosphate-buffered saline (PBS) and incubated at 37 degrees C. The PBS was changed daily, and the removed PBS samples were stored at -70 degrees C until the antibiotic in each sample was determined by microbiological disk diffusion assay. Nondissolving PMMA beads with tobramycin and clindamycin had concentrations well above breakpoint sensitivity concentrations (i.e., the antibiotic concentrations at the transition point between bacterial killing and resistance to the antibiotic) for more than 90 days, but vancomycin concentrations dropped by day 12. ALl PLA, PL:CG, and the 2,000-MW PLA-70:30 PL:CG biodegradable beads release high concentrations of all the antibiotics in vitro for the period of time needed to treat bone infections (i.e., 4 to 8 weeks). Antibiotic-loaded PLA and PL:CG beads have the advantage of better antibiotic elution and the ability to biodegradable (thereby averting the need for secondary surgery for bead removal) compared to the PMMA beads presently used in the clinical setting.