Tag Archive | Infection

Fructosamine Bests HbA1c for Preop Glycemic Screening

Fructosamine for OBuzzPatients with diabetes have an increased risk of postoperative complications following total joint arthroplasty (TJA). Additionally, perioperative hyperglycemia has been identified as a common and independent risk factor for periprosthetic joint infection, even among patients without diabetes. Therefore, knowing a patient’s glycemic status prior to surgery is very helpful.

In the November 15, 2017 edition of The Journal of Bone & Joint Surgery, Shohat et al. demonstrate that serum fructosamine, a measure of glycemic control obtainable via a simple and inexpensive blood test, is a good predictor of adverse outcomes among TJA patients—whether or not they have diabetes.

Researchers screened 829 patients undergoing TJA for serum fructosamine and HbA1c—a common measure, levels of which <7% are typically considered good glycemic control. Patients with fructosamine levels ≥292 µmol/L had a significantly higher risk of postoperative deep infection, readmission, and reoperation, while HbA1c levels ≥7% showed no significant correlations with any of those three adverse outcomes. Among the 51 patients who had fructosamine levels ≥292 µmol/L, 39% did not have HbA1c levels ≥7%, and 35% did not have diabetes.

In addition to being more predictive of postsurgical complications than HbA1c, fructosamine is also a more practical measurement. A high HbA1c level during preop screening could mean postponing surgery for 2 to 3 months, while the patient waits to see whether HbA1c levels come down. Fructosamine levels, on the other hand, change within 14 to 21 days, so patients could be reassessed for glycemic control after only 2 or 3 weeks.

While conceding that the ≥292 µmol/L threshold for fructosamine suggested in this study should not be etched in stone, the authors conclude that “fructosamine could serve as the screening marker of choice” for presurgical glycemic assessment. However, because the study did not examine whether correcting fructosamine levels leads to reduced postoperative complications, a prospective clinical trial to answer that question is needed.

What’s New in Shoulder and Elbow Surgery 2017

Shoulder & elbowEvery month, JBJS publishes a Specialty Update—a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Click here for a collection of all OrthoBuzz Specialty Update summaries.

This month, Aaron Chamberlain, MD, co-author of the October 18, 2017 Specialty Update on shoulder and elbow surgery, selected the most clinically compelling findings from among the 36 studies summarized in the Specialty Update.

Reverse Shoulder Arthroplasty
With reverse shoulder arthroplasty, surgeons often have difficulty setting expectations for patients due to the lack of long-term outcomes data. Bacle et al. published a study that describes the clinical outcomes in patients with at least 10 years’ follow-up. Medium-term outcomes among  an original cohort of 186 patients had been previously described. Eighty-four of those original patients were available for a mean long-term follow-up of 150 months. The mean overall Constant score fell from 63 at medium-term follow-up to 55 at final follow-up.  Active anterior elevation also decreased from 138° to 131.° Despite the decrease in Constant score and ROM between mid- and long-term follow-up, these two measures remained significantly better than preoperative values. Analysis showed a 93% implant survival probability at 120 months. This study will help surgeons counsel patients regarding long-term expectations after reverse shoulder arthroplasty – especially as younger patients are increasingly indicated for this procedure.

Rotator Cuff Repair
A central focus of studies evaluating rotator cuff repair has been to better understand the biological environment that influences tendon healing. Greater understanding of the genetic influence in rotator cuff pathology may lead to interventions that could improve the healing environment.  Tashjian et al. reported outcomes after arthroscopic rotator cuff repair in 72 patients who were assessed for family history of rotator cuff tears and underwent a genetic analysis looking for variants in the estrogen-related receptor beta (ESRRB) gene.1 Positive family history and tear retraction were associated with a failure of healing, and lateral tendon retears were associated with both family history and the presence of a single nucleotide polymorphism in the ESRRB gene.

In another recent study focused on the biological healing environment after rotator cuff repair, a prospective randomized trial of platelet-rich plasma (PRP) in patients undergoing repair of a medium to large-sized rotator cuff tear2 found that patients who received PRP experienced an increase in vascularity at the repair site up to 3 months postoperatively. The PRP group also demonstrated better Constant-Murley and UCLA scores and lower retear rates than the no-PRP group, but there was no difference in ASES scores. In another recent randomized trial, 120 patients were randomized to either PRP or ropivacaine injection after rotator cuff repair.3 No between-group differences in clinical outcome scores or retear rates were identified. The contrasting results of these two recent randomized studies illustrate the challenge of identifying any conclusive benefit of PRP in the setting of rotator cuff repair.

Prosthetic Shoulder Infection
Accurate diagnosis of prosthetic shoulder infection continues to present a formidable challenge, given the difficulty of detecting Proprionibacterium acnes (P. acnes) and interpreting when positive results are clinically significant. Development of P. acnes tests that are more rapid and precise in identifying clinically significant infections would be of significant value.  Holmes et al. evaluated a PCR restriction fragment length polymorphism (RFLP) technique to identify P. acnes from infected tissue in the shoulder.4 In this study, within 24 hours of sampling, the PCR-RFLP assay detected P. acnes-specific amplicons in as few as 10 bacterial cells.

Clavicle Fractures
Approaches to managing clavicle fractures have evolved significantly over the past several decades. While it was once generally accepted that middle third clavicle fractures should be managed nonoperatively, multiple studies have described concerning rates of nonunions and symptomatic malunions. A multicenter prospective trial that randomized patients to either surgical fixation with a plate or nonoperative management identified a nonunion rate of 23.1% in the nonoperatively managed group, compared with a 2.4% nonunion rate in the surgically treated group (p<0.0001). However, the rate of secondary operations was 27.4% in the operatively treated group (most for plate removal) versus 17.1% in the nonoperative group, although that difference did not reach statistical significance (p=0.18). These results will help inform discussions between providers and patients when considering management options for midshaft clavicle fractures.

References

  1. Tashjian RZ, Granger EK, Zhang Y, Teerlink CC, Cannon-Albright LA. Identification of a genetic variant associated with rotator cuff repair healing. J Shoulder Elb Surg. 2016. doi:10.1016/j.jse.2016.02.019.
  2. Pandey V, Bandi A, Madi S, et al. Does application of moderately concentrated platelet-rich plasma improve clinical and structural outcome after arthroscopic repair of medium-sized to large rotator cuff tear? A randomized controlled trial. J Shoulder Elb Surg. 2016;26(3):e82-e83. doi:10.1016/j.jse.2016.01.036.
  3. Flury M, Rickenbacher D, Schwyzer H-K, et al. Does Pure Platelet-Rich Plasma Affect Postoperative Clinical Outcomes After Arthroscopic Rotator Cuff Repair? Am J Sports Med. 2016. doi:10.1177/0363546516645518.
  4. Holmes S, Pena Diaz AM, Athwal GS, Faber KJ, O’Gorman DB. Neer Award 2017: A rapid method for detecting Propionibacterium acnes in surgical biopsy specimens from the shoulder. J Shoulder Elb Surg. 2017. doi:10.1016/j.jse.2016.10.001.

New Hope for New Bone After Osteomyelitis Debridement

Osteomyelitis Tibia for OBuzzThis basic science tip comes from Fred Nelson, MD, an orthopaedic surgeon in the Department of Orthopedics at Henry Ford Hospital and a clinical associate professor at Wayne State Medical School. Some of Dr. Nelson’s tips go out weekly to more than 3,000 members of the Orthopaedic Research Society (ORS), and all are distributed to more than 30 orthopaedic residency programs. Those not sent to the ORS are periodically reposted in OrthoBuzz with the permission of Dr. Nelson.

One clinical frustration following osteomyelitis debridement is poor bone healing. Impaired bone homeostasis provokes serious variations in bone remodeling that involve multiple inflammatory cytokines.

The chemokines CCL2, CCL3, and CXCL2 are known to be strong chemoattractants for neutrophils during inflammatory states, and they play a role during osteoclastogenesis. B cells are also activators of osteoclastognesis and are regulated, in part, by tissue inhibitor of metalloprotease 1 (TIMP-1).

Researchers drilled a 1 mm hole into the proximal tibia of 126 mice. In half of the mice (63), a dose of S. aureus was injected into the canal, while the controls had no bacteria injected. At two weeks, all proximal tibiae were debrided; cultures were taken 3 and 7 days after debridement to assure no residual infection. Cytokine assays and Western blots for CCL2, CCL3, CXCL2, TIMP-1, RANKL, and TNF-α were performed in selected mice in each group. Flow cytometry and histology were also done in selected mice in each group.

In the osteomyelitis group, Western blot analysis identified increased levels of CCL2, CCL3, and CXCL2. Histology revealed increased osteoclastogenesis after osteomyelitis debridement, with calcitonin-receptor and RANKL detection via immunohistochemical and fluorescence staining. There was diminished osteogenesis and proliferation in the osteomyelitis group, but TNF-α expression seemed to have no effect on altered bone regeneration after bone infection. Flow cytometry revealed elevated B cell activity in the osteomyelitis group, with subsequent increased osteoclast activity and accelerated bone resorption.

The researchers propose a RANKL-dependent osteoclastogenesis after debridement for osteomyelitis that is associated with elevated B cells and decreased osteogenesis. These findings could lead to new interventions to improve bone healing during the course of osteomyelitis treatment, particularly following debridement.

Reference
Wagner JM, Jaurich H, Wallner C, Abraham S, Becerikli M, Dadras M, Harati K, Duhan V, Khairnar V, Lehnhardt M, Behr B. Diminished bone regeneration after debridement of posttraumatic osteomyelitis is accompanied by altered cytokine levels, elevated B cell activity, and increased osteoclast activity. J Orthop Res. 2017 Mar 6. doi: 10.1002/jor.23555. [Epub ahead of print] PMID: 28263017

Unplanned Readmissions After Outpatient Hand and Elbow Surgery

swiontkowski-marc-colorIn the April 5, 2017 issue of The Journal, Noureldin et al. analyzed more than 14,000 procedures from the NSQIP database to determine the rate of unplanned 30-day readmission after outpatient surgical procedures of the hand and elbow. The 1.2% rate seems well within the range of acceptability, particularly because the more than 450 institutions contributing to this database probably serve populations who don’t have the best overall health and comorbidity profiles.

Missing causes for about one-third of the readmissions illustrate one issue with data accuracy in these large administrative datasets. While the authors acknowledged a “lack of granularity” as the greatest limitation in analyzing large databases, they added that the readmissions with no listed cause “were likely unrelated to the principal procedure.”

It was not surprising that infection was the most common cause for readmission. However, it would have been nice to know the rate of confirmed infection via positive cultures, as I suspect many of these patients were readmitted for erythema, swelling, warmth, and discomfort associated with postoperative hematoma rather than infection.

Regardless of the need for higher-quality data on complications following outpatient orthopaedic surgical procedures, this analysis gives us more confidence that the move toward outpatient surgical care in our specialty is warranted. I think most patients would rather sleep in their own home as long as preoperative comorbidities and ASA levels are considered and adequate postoperative pain control can be achieved in an outpatient setting. The trend toward outpatient orthopaedic treatment is likely to continue as we gather higher-quality data and better understand the risk-benefit profile.

Marc Swiontkowski, MD
JBJS Editor-in-Chief

Smoking Boosts Rate of Reoperation for Infection after TJA

Smoking Image from Nick.jpegHere’s one thing about which medical studies have been nearly unanimous:  Smoking is a health hazard by any measure. In the February 15, 2017 edition of The Journal of Bone & Joint Surgery, Tischler et al. put some hard numbers on the risk of smoking for those undergoing total joint arthroplasty (TJA).

After controlling for confounding factors, the authors of the Level III prognostic study found that:

  • Current smokers have a significantly increased risk of reoperation for infection within 90 days of TJA compared with nonsmokers.
  • The amount one has smoked, regardless of current smoking status, significantly contributed to increased risk of unplanned nonoperative readmission.

In a commentary on the Tischler et al. study, William, G. Hamilton, MD says, “…as physicians, we should work cooperatively with our patients to enhance outcomes by attempting to reduce these modifiable risk factors. We can educate patients and can suggest smoking cessation programs and weight loss regimens that may not only improve the risk profile during the surgical episode, but also improve the patients’ overall health.”

Whence P. Acnes in Shoulder Arthroplasty?

p-acnes-pie-chartPropionibacterium acnes is a frequently isolated pathogen in postoperative shoulder infections, but where exactly does it come from? According to a study by Falconer et al. in the October 19, 2016 Journal of Bone & Joint Surgery, P. acnes derives from the subdermal edges of the surgical incision and spreads through contact with the surgeon’s gloves and surgical instruments.

The authors obtained specimens for microbiological analysis at five different sites from 40 patients undergoing primary shoulder arthroplasty. Thirty-three percent of the patients had at least one culture specimen positive for P. acnes, and the most common site of P. acnes growth was the subdermal layer, followed by forceps.

The authors observed no clinical postoperative infections during the follow-up of 6 to 18 months, although that is a relatively short investigation period for a pathogen that often causes late-onset indolent infections. The authors conclude that “it is likely that surgeon handling of the skin and subdermal layer contaminates the rest of the surgical field.” Although the study did not investigate preventive techniques, based on the findings the authors suggest the following possible prophylactic approaches:

  • Minimizing handling of the subdermal layer
  • Changing gloves after the dermis is cut
  • Avoiding contact between implants and the subdermal layer
  • Repeating use of antibacterial agents once the wound is opened

JBJS Reviews Editor’s Choice–Open Fracture Care During War

War Wound.jpgInjuries to the musculoskeletal system are among the most common wounds of war. Compared with extremity injuries in the civilian population, injuries sustained in combat tend to be due to high-energy explosions and are associated with a greater degree of contamination and a longer timeline for recovery and healing. Importantly, the sequelae of musculoskeletal injuries sustained during combat tend to lead to more long-term disability than those affecting other organ systems.

In this month’s Editor’s Choice article, Rivera et al. review the current literature on combat injuries of the lower extremity and suggest that explosions are the most common mechanism of injury encountered by deployed service members. While exposure to an explosion does not necessarily result in a specific limb injury, the explosion mechanism does contribute to more severe injuries. Moreover, among service members who sustain open fractures of the tibia, foot, and ankle, infection is a common complication and is associated with more severe soft-tissue injury. As a result, surgeons who are deployed in combat settings are now performing more fasciotomies for limbs that are at risk. However, the outcomes and complication rates associated with these procedures are not well established, and the causes of late amputations are not always clear.

As part of a comprehensive review of this topic, Rivera et al. pose 3 important clinical questions that are ideal for translational research investigation. First, they ask, “What is the best way to manage and transport patients who have severe open fractures in order to minimize infection?” Indeed, while negative-pressure wound therapy (NPWT) appears to be a promising wound-care technique, additional study is needed in order to know how to best augment the standard of care for battlefield medicine. Second, “What is the best way to treat fasciotomy wounds and the late sequelae of the compartment syndrome?” In order to answer this question, a broader understanding of compartment syndrome detection and the indications for surgical treatment are needed. Finally, “What is the best way to select limbs for salvage and to optimize the reconstruction of injured tissues?” This question must explore not only the patient’s perspective but also the multitude of causes that lead to late amputation.

Thomas A. Einhorn, MD
Editor, JBJS Reviews

How Safe Are Osseointegrated Implants for Amputees?

Osseointegrated Implant.gifAbout one-third of lower-limb amputees have problems with the socket connecting their residuum to a prosthetic limb. This has led to the development of osseointegrated implants, which consist of a press-fit intramedullary implant that protrudes through the skin to accommodate an abutment to which the prosthetic limb is rigidly attached.

Concerns about ascending infection and related complications with such constructs led Al Muderis et al. to conduct a multicenter prospective cohort study on the safety of osseointegrated implants, published in the June 1, 2016 JBJS. The authors found that mild infection and irritation of soft tissue were common, but that “these complications can be managed with simple measures,” such as outpatient antibiotic treatment.

Specifically, among the 86 patients with a transfemoral amputation and an implant who were followed for a median of 34 months:

  • 31 had no complications
  • 29 had one or more infections (all grade 1 or 2, four of which required surgical debridement)
  • 26 had non-infectious complications (including hypergranulation of the stoma, soft-tissue redundancy, traumatic intertrochanteric fracture, and intramedullary implant breakage)

Smoking and female sex were associated with recurrent and more severe infections, prompting the authors to suggest that those patient characteristics could be “useful criteria for patient counseling and selection.”

In their commentary on the study, Paul Dougherty, MD and Douglas Smith, MD encourage continued research into bactericidal or mechanical barriers to microbial colonization in areas where the implant enters the body. Although no formal cost studies have been done on osseointegrated implants, the commentators reckon that such costs “are likely greater than those for conventional prosthetic management.”

JBJS Webinar: How to Prevent and Treat MSK Infections

MRSA Resistance.gifMusculoskeletal (MSK) infections are highly prevalent and potentially serious, and orthopaedists are frequently faced with preventing and treating them. Wherever or however they are acquired, these pathogen-based conditions are among the most challenging to address effectively.

On Monday, May 23, 2016 at 8:00 pm EDT, The Journal of Bone & Joint Surgery will present a complimentary webinar that includes findings from two recent JBJS studies that explore how best to prevent deep infections in lower-grade open fractures, and the most effective antibiotics for treating community-acquired hand infections.

Richard Jenkinson, MD will discuss findings from a cohort study that compared deep infection rates in patients with lower-grade open fractures who were treated with either immediate wound closure or delayed wound closure. Rick Tosti, MD will examine resistance patterns of specific antibiotics to MRSA infections of the hand in an urban population.

Moderated by musculoskeletal-infection expert Jonathan Schoenecker, MD, PhD, the webinar will also feature commentaries on the studies by Lawrence Marsh, MD and Isaac Thomsen, MD.

Click here to register.

What’s New in Pediatric Orthopaedics

Every month, JBJS publishes a Specialty Update—a review of the most pertinent and impactful studies published in the orthopaedic literature during the previous year in 13 subspecialties. Here is a summary of selected findings cited in the February 17, 2016 Specialty Update on pediatric orthopaedics:

Guidelines and AUCs

–The AAOS updated its clinical practice guidelines on the treatment of pediatric diaphyseal femoral fractures1 and adopted appropriate use criteria (AUC) for pediatric supracondylar humeral fractures with vascular injury.2

Spine

–A matched case control study of surgical spinal procedures found that neuromuscular scoliosis, weight for age ≥95th percentile, ASA score of ≥3, and prolonged operative time were associated with a higher risk of surgical site infection.3

–Several groups, including the Scoliosis Research Society and POSNA, endorsed the definition of early-onset scoliosis as “scoliosis with onset less than the age of ten years, regardless of etiology.”4, 5

–A prospective randomized study found that preoperative education and orientation for scoliosis surgery paradoxically increased immediate postoperative anxiety among patients and caregivers, relative to controls who received standard perioperative information.6

–A randomized trial investigating perioperative blood loss and transfusion rates in patients undergoing posterior spinal arthrodesis for adolescent idiopathic scoliosis found that tranexamic acid and  epsilon-aminocaproic acid reduced operative blood loss but not transfusion rates when compared with placebo.

Hip

–A study of 30 patients with severe stable slipped capital femoral epiphysis found that good or excellent results were achieved over 2.5 years in a higher proportion of those receiving a modified Dunn realignment compared with those treated with in situ fixation. The reoperation rate was greater in the in situ fixation cohort.7

–A prospective study analyzing complications after periacetabular osteotomy for acetabular dysplasia using the modified Clavien-Dindo grading scheme found grade III or IV complications in 5.9% of 205 patients, with a nonsignificant trend associating complications with male sex and obesity.

–A registry-based study found that, compared with matched controls, patients with Legg-Calve-Perthes disease had an elevated hazard ratio of 1.5 for ADHD, 1.3 for depression, and 1.2 for mortality. It remains unclear whether patients with Legg-Calve-Perthes disease would benefit from routine psychiatric screening.8

Sports Medicine

–A case control study of 822 injured athletes and 368 uninjured athletes found that overuse injuries represented 67.4% of all injuries. The risk of serious overuse injury was two times greater if the weekly hours of sports participation were greater than the athlete’s age in years.9

–A meta-analysis of initial nonoperative treatment compared with operative treatment of ACL tears in children and adolescents noted instability and pathologic laxity in 75% of patients with nonoperative treatment compared with 14% of patients following reconstruction.10

Trauma

–A review of more than 4,400 supracondylar humeral fractures with isolated anterior interossesous nerve palsies but without sensory nerve injury or dysvasculartity found that postponing treatment for up to 24 hours did not delay neurologic recovery.

–A randomized controlled trial investigating the effectiveness of analgesics during intraossesous pin removal found that acetaminophen and ibuprofen were clinically equivalent to placebo in terms of pain reduction and heart rate.

Foot and Ankle

–A study exploring risk factors for failure of allograft bone after calcaneal lengthening osteotomy found a lower risk of failure with tricortical iliac crest allograft relative to patellar allograft. The risk of radiographic graft failure increased with patient age.11

–A prospective nonrandomized study of symptomatic planovalgus feet comparing subtalar arthroereisis with lateral column lengthening found similar postoperative improvements and complication rates in both groups after one year.12

Musculoskeletal Infection & Neuromuscular Conditions

–A cohort study of 869 children with osteomyelitis, septic arthritis, pyomyositis, or abscess concluded that routinely culturing for anaerobic, fungal, and acid-fast bacterial organisms is not recommended except in patients with a history of penetrating injury, immunocompromise, or failure of primary treatment.

–A prospective study comparing tendon transfers, botulinum toxin injections, and ongoing therapy in children with upper-extremity cerebral palsy found that tendon transfer demonstrated greater improvements than the alternatives in joint positioning during functional tasks and grip and pinch strength.

References

  1. American Academy of Orthopaedic Surgeons.Guideline on the treatment of pediatric diaphyseal femur fractures. 2015.http://www.aaos.org/Research/guidelines/PDFFguideline.asp.
  2. American Academy of Orthopaedic Surgeons.Appropriate use criteria: pediatric supracondylar humerus fractures with vascular injury. 2015.http://www.aaos.org/research/Appropriate_Use/pshfaucvascular.asp.
  3. Croft LD, Pottinger JM, Chiang HY, Ziebold CS, Weinstein SL, Herwaldt LA. Risk factors for surgical site infections after pediatric spine operations. Spine (Phila Pa 1976). 2015 Jan 15;40(2):E112-9
  4. El-Hawary R, Akbarnia BA. Early onset scoliosis – time for consensus. Spine Deformity. 2015 Mar;3(2):105-6
  5. Skaggs DL, Guillaume T, El-Hawary R, Emans J, Mendelow M, Smith J. Early onset scoliosis consensus statement, SRS Growing Spine Committee, 2015. Spine Deformity. 2015;3(2):107.
  6. Rhodes L, Nash C, Moisan A, Scott DC, Barkoh K, Warner WC Jr, Sawyer JR, Kelly DM.Does preoperative orientation and education alleviate anxiety in posterior spinal fusion patients? A prospective, randomized study. J Pediatr Orthop. 2015 Apr-May;35(3):276-9.
  7. Novais EN, Hill MK, Carry PM, Heare TC, Sink EL. Modified Dunn procedure is superior to in situ pinning for short-term clinical and radiographic improvement in severe stable SCFE. Clin Orthop Relat Res. 2015 Jun;473(6):2108-17. Epub 2014 Dec 12
  8. Hailer YD, Nilsson O. Legg-Calvé-Perthes disease and the risk of ADHD, depression, and mortality. Acta Orthop. 2014 Sep;85(5):501-5. Epub 2014 Jul 18.
  9. Jayanthi NA, LaBella CR, Fischer D, Pasulka J, Dugas L. Sports-specialized intensive training and the risk of injury in young athletes: a clinical case-control study. Am J Sports Med. 2015 Apr;43(4):794-801. Epub 2015 Feb 2.
  10. Ramski DE, Kanj WW, Franklin CC, Baldwin KD, Ganley TJ. Anterior cruciate ligament tears in children and adolescents: a meta-analysis of nonoperative versus operative treatment. Am J Sports Med. 2014 Nov;42(11):2769-76. Epub 2013 Dec 4.
  11. Lee IH, Chung CY, Lee KM, Kwon SS, Moon SY, Jung KJ, Chung MK, Park MS. Incidence and risk factors of allograft bone failure after calcaneal lengthening. Clin Orthop Relat Res. 2015 May;473(5):1765-74. Epub 2014 Nov 14.
  12. Chong DY, Macwilliams BA, Hennessey TA, Teske N, Stevens PM. Prospective comparison of subtalar arthroereisis with lateral column lengthening for painful flatfeet. J Pediatr Orthop B. 2015 Jul;24(4):345-53.