Local administration of morphine for analgesia after iliac bone graft harvest

Publication retraction in spine surgery: a systematic review

PURPOSE

The number of articles retracted by peer-reviewed journals has increased in recent years. This study systematically reviews retracted publications in the spine surgery literature.

METHODS

A search of PubMed MEDLINE, Ovid EMBASE, Retraction Watch, and the independent websites of 15 spine surgery-related journals from inception to September of 2022 was performed without language restrictions. PRISMA guidelines were followed with title/abstract screening, and full-text screening was conducted independently and in duplicate by two reviewers. Study characteristics and bibliometric information for each publication was extracted.

RESULTS

Of 250 studies collected from the search, 65 met the inclusion criteria. The most common reason for retraction was data error (n = 15, 21.13%), followed by plagiarism (n = 14, 19.72%) and submission to another journal (n = 14, 19.72%). Most studies pertained to degenerative pathologies of the spine (n = 32, 80.00%). Most articles had no indication of retraction in their manuscript (n = 24, 36.92%), while others had a watermark or notice at the beginning of the article. The median number of citations per retracted publication was 10.0 (IQR 3-29), and the median 4-year impact factor of the journals was 5.05 (IQR 3.20-6.50). On multivariable linear regression, the difference in years from publication to retraction (p = 0.0343, β = 6.56, 95% CI 0.50-12.62) and the journal 4-year impact factor (p = 0.0029, β = 7.47, 95% CI 2.66-12.28) were positively associated with the total number of citations per retracted publication. Most articles originated from China (n = 30, 46.15%) followed by the United States (n = 12, 18.46%) and Germany (n = 3, 4.62%). The most common study design was retrospective cohort studies (n = 14, 21.54%).

CONCLUSIONS

The retraction of publications has increased in recent years in spine surgery. Researchers consulting this body of literature should remain vigilant. Institutions and journals should collaborate to increase publication transparency and scientific integrity.

Osseointegration Aspects of Implants at the Bone Reconstruction Site by a Novel Porous Titanium Scaffold

OBJECTIVES

Porous titanium is used for the reconstruction of large bone defects due to its excellent mechanical strength. The quality of osseointegration of implants placed in bone reconstructed with porous titanium is unknown. The purpose of this in vivo study was to evaluate the osseointegration of implants at sites reconstructed using porous titanium.

MATERIAL AND METHODS

Hollow porous titanium (Ti) (outer-diameter 6 mm, inner-diameter 2 mm, length 4 mm, 85% porosity) and similar-sized porous hydroxyapatite (porous HA: 75% porosity) samples were prepared and implanted in 6 New Zealand white rabbit femurs. Four weeks later, an implant bed was created to receive a Ti implant (diameter 2 mm, length 4 mm). An implant placed at a pristine bone site served as the control. Four weeks later, histological and histomorphometric evaluations of the test and control sites were conducted.

RESULTS

Osseointegration was observed in all groups. There was no significant difference in the bone formation ratio and bone-implant contact (BIC) ratio across all groups for the whole area. At the cancellous bone area of the bone defect, superior bone formation ratio and BIC ratio were observed with porous Ti and porous HA compared to the control (bone formation ratio: control 1.8 [SD 3]%, HA 23 [SD 3]%, Ti 23.6 [SD 5]%; BIC ratio: control 5.4 [SD 5.3]%, HA 28.9 [SD 10.7]%, Ti 41.6 [SD 14]%). Porous Ti demonstrated good osteoconduction and osseointegration abilities, similar to porous HA.

CONCLUSIONS

To our knowledge, this is the first report of implant treatment after preliminary bone reconstruction using a titanium biomaterial. Porous titanium is a suitable material for bone reconstruction before implant treatment in load-bearing areas that allow subsequent prosthetic treatment.

A stability evaluation of a novel titanium dental implant/interconnected porous hydroxyapatite complex under functional loading conditions

The aim of this study was to evaluate the stability of implant/interconnected porous calcium hydroxyapatite complex (implant/IPCHA-complex) under functional loading. Implant/IP-CHA-complexes were placed into the mandibles of four Beagle-Labrador hybrid dogs (complex-group). On the other side, an implant was placed directly (control-group). To subject the loading, the animals were fed a hard diet throughout the loading phase of 5 months. The implant stability quotients (ISQs) and bone implant contact (BIC), and histological evaluations were performed. The ISQs of implant/IP-CHA-complex was significantly lower at placement than that of the control-implant. On the other hand, there was no significant difference between in the groups during loading. The BIC measurements, there was no significantly difference between in both groups. Histologically, newly formed bone was observed in contact with most of the implant surface in the complex-group. An IP-CHA/implant-complex would be able to achieve both bone reconstruction and implant stability under functional loading conditions.

Osseointegration aspects of placed implant in bone reconstruction with newly developed block-type interconnected porous calcium hydroxyapatite

Artificial bone has been employed to reconstruct bone defects. However, only few reports on implant placement after block bone grafting exist.

Modified Iliac Crest Reconstruction with Bone Cement for Reduction of Donor Site Pain and Morbidity after Open Wedge High Tibial Osteotomy: A Prospective Study

Purpose

This study was to determine the efficacy of iliac crest reconstruction using bone cement in reducing pain and morbidity at the donor site in patients undergoing open wedge high tibial osteotomy (OWHTO) with tricortical iliac crest autologous graft.

Materials and Methods

Thirty-three patients who underwent iliac crest reconstruction using polymethyl methacrylate (PMMA) bone cement (group A) and thirty patients who had no iliac crest reconstruction (group B) were enrolled in this study. All patients were evaluated for pain and functional disability related to graft harvesting using the pain and functional visual analogue scale (VAS) score during hospital stay and at 6 weeks, 3 months, and 6 months postoperatively.

Results

There was significant difference between the two groups in terms of pain and function. The pain VAS score was significantly lower in group A than group B during the first 2 weeks postoperatively (p=0.04) and the functional VAS score was also significantly lower in group A during the first 2 weeks postoperatively (p<0.001) in terms of breathing, sitting up from the supine position, and standing up with crutches from the sitting position.

Conclusions

Iliac crest donor site reconstruction using PMMA bone cement in patients undergoing OWHTO significantly decreased pain and improved function during the first 2 weeks postoperatively when compared to patients who underwent OWHTO without iliac crest reconstruction.

Inorganic polyphosphate adsorbed onto hydroxyapatite for guided bone regeneration: an animal study

Inorganic polyphosphate (poly(P)) is recognized as a therapeutic agent that promotes fibroblast growth factor and enhances osteogenic differentiation, and in vivo, when adsorbed onto interconnected porous calcium hydroxyapatite (IP-CHA) enhances bone regeneration. The present study focused on the effect of poly(P) adsorbed onto IP-CHA granules (Poly(P)/IP-CHA) in guided bone regeneration (GBR). Dental implants were placed into the edentulous mandibular areas of five Beagle-Labrador hybrid dogs with screw expose on the buccal side, and then bone defects were filled Poly(P)/IP-CHA (test) or IP-CHA (control). After 12 weeks, histological evaluation and histomorphometrical analysis were performed. Newly-bone formation around exposed implant screw was clearly detected in the test-group. The ratio for regenerated bone height in the test group versus the control-group was 85.6±20.2 and 62.6±23.8, respectively, with no significant difference, while, that for bone implant contact was significantly higher (67.9±11.8 and 48.8±14.1, respectively). These findings indicate that Poly(P)/IP-CHA enhances bone regeneration in GBR.

Evaluation of analgesic effect of local administration of morphine after iliac crest bone graft harvesting: A double blind study

Background and Objective:

Pain is a complex process influenced by both physiological and psychological factors. In spite of an armamentarium of analgesic drugs and techniques available to combat post-operative pain, appropriate selection, and effective management for relief of post-operative pain still poses unique challenges. The discovery of peripheral opioid receptors has led to growing interest in the use of locally applied opioids (intra-articular, intra-pleural, intra-peritoneal, and perineural) for managing acute pain. As bone graft harvesting is associated with significant post-operative pain and there is a paucity of literature on the use of peripheral opioids at the iliac crest bone harvesting site, the present study was planned to evaluate the analgesic efficacy of local administration of morphine after iliac crest bone graft harvesting.

Materials and Methods:

A total of 60 patients, 20-50 years of age scheduled to undergo elective surgery for delayed and non-union fracture both bone leg with bone grafting under general anaesthesia (GA) were randomly assigned to one of the four groups of 15 patients each: group 1: 2.5 ml normal saline (NS) +2.5 ml NS infiltrated into the harvest site at 2 sites + 1 ml NS intramuscularly (i/m); Group 2: 2.5 ml NS + 2.5 ml NS infiltrated into the harvest site at 2 sites + 5 mg morphine in 1 ml i/m.; Group 3: 2.5 mg (2.5 ml) morphine + 2.5 mg (2.5 ml) morphine infiltrated into the harvest site at 2 sites + 1 ml NS i/m; Group 4: 0.5 mg naloxone (2.5 ml) +5 mg (2.5 ml) morphine infiltrated into the harvest site at 2 sites + 1 ml NS i/m. Pain from the bone graft site and operative site was assessed for 24 h post-operatively.

Results:

The patients who had received morphine infiltration (Group 3) had significantly less pain scores at the graft site at 4, 6, and 10 post-operative hours. They also had significantly less morphine consumption and overall better pain relief as compared to the other groups.

Conclusions:

Morphine administered peripherally provided better analgesia as compared to that given systemically and this effect was noticeable after 4 h post-operatively.

Pain from donor site after anterior cervical fusion with bone graft: a prospective randomized study with 12 months of follow-up

INTRODUCTION

Harvesting bone graft from the iliac crest in spinal fusion surgery is a widely used technique. However, complications can occur and there are also reports of patients with persistent graft site pain after surgery. The aim of this study was to evaluate pain from the donor site (DS) over time, and register associated complications and if it affected health-related quality of life (HRQoL).

MATERIAL AND METHODS

One hundred and seven patients participating in an RCT between two different methods of reconstruction after cervical decompression were included in this study. One group underwent surgery with bone graft (BG) from the iliac crest and the other with no bone graft (NBG). All patients were evaluated concerning pain at DS and HRQoL preoperatively, at 4 weeks, 3 months and 1 year. Pain was evaluated with visual analog scale (VAS) and HRQoL with EQ-5D.

RESULTS

A statistically significant difference was found at all times of follow-up in the BG group compared to preoperative levels and the NBG group. The VAS levels at follow-ups at 3 months and 1 year were however of questionable clinical importance. Two patients in the BG group had superficial wound infections postoperatively and five patients still had sensory disturbance in the area of graft site at 12 months. No major complications were registered. No difference could be seen in EQ-5D at any time of follow-up between the groups.

CONCLUSION

Harvesting of iliac crest bone graft is associated with significant pain. However, at 3 months postoperatively, the negative effect of clinical importance seemed to have disappeared compared to when no bone graft was harvested. The pain from bone graft harvesting does not seem to affect the quality of life at 4 weeks postoperatively and onward.

Retracted publications in the drug literature

Recent studies have suggested an increase in the number of retracted scientific publications. It is unclear how broadly the issue of misleading and fraudulent publications pertains to retractions of drug therapy studies. Therefore, we sought to determine the trends and factors associated with retracted publications in drug therapy literature. A PubMed search was conducted to identify retracted drug therapy articles published from 2000-2011. Articles were grouped according to reason for retraction, which was classified as scientific misconduct or error. Scientific misconduct was further divided into data fabrication, data falsification, questions of data veracity, unethical author conduct, and plagiarism. Error was defined as duplicate publication, scientific mistake, journal error, or unstated reasons. Additional data were extracted from the retracted articles, including type of article, funding source, author information, therapeutic area, and retraction issue. A total of 742 retractions were identified from 2000-2011 in the general biomedical literature, and 102 drug studies met our inclusion criteria. Of these, 73 articles (72%) were retracted for a reason classified as scientific misconduct, whereas 29 articles (28%) were retracted for error. Among the 73 articles classified as scientific misconduct, those classified as unethical author conduct (32 articles [44%]) and data fabrication (24 articles [33%]) constituted the majority. The median time from publication of the original article to retraction was 31 months (range 1-130). Fifty percent of retracted articles did not state a funding source, whereas pharmaceutical manufacturer funding accounted for only 13 articles (13%) analyzed. Many retractions were due to repeat offenses by a small number of authors, with nearly 40% of the retracted studies associated with two individuals. We found that a greater proportion of drug therapy articles were retracted for reasons of misconduct and fraud compared with other biomedical studies. It is important for health care practitioners to monitor the literature for retractions so that recommendations for drug therapy and patient management may be modified accordingly.

Peripheral catheter techniques

With ultrasound, continuous peripheral nerve blocks (CPNBs) are one of the most recent developments in regional anesthesia in children. CPNBs are now used more widely in children because more suitable materials have been marketed, allowing complete, and prolonged postoperative pain control. Their use after orthopedic procedures in children and treatment for complex regional pain syndrome in adolescents has demonstrated the benefits. Perineural catheters have also shown their superiority over other techniques of continuous regional anesthesia in terms of side effects. The efficiency and the safety of these techniques may facilitate early ambulation with improved pain management, treatment at home with disposable pumps, and improved rehabilitation of children. Studies on large cohorts of patients published to date have failed to highlight any severe complications in their use compared with other adult studies. Accidents owing to systemic toxicity are very unlikely if the recommended maximum dose is not exceeded. The safety of continuous regional anesthesia techniques in children relies on the use of low-concentration l-enantiomer solutions (ropivacaine or levobupivacaine) accompanied by low plasma concentrations of local anesthetics, limiting the risk of systemic toxicity of these molecules. CPNB can ensure strong and lasting analgesia in hospital or at home.

Chemical analgesia for velvet antler removal in deer

There is a legal requirement to provide analgesia for velvet antler removal in New Zealand. Currently, this is achieved using local anaesthetic blockade, with or without systemically administered sedative/analgesic agents, or by compression in 1-year-old stags. Lignocaine hydrochloride 2% is most commonly used and is most effective when administered as a high-dose ring block. Combinations of various amino-amide local anaesthetic agents can achieve rapid onset and prolonged duration of analgesia, though concerns about drug residues and carcinogenic potential of a lignocaine metabolite have led to consideration of the amino-ester family of local anaesthetics as alternatives. Systemically administered analgesics, including opioids, alpha-2-adrenergic agents and ketamine provide dose-dependent sedation and analgesia. However, none are sufficient, alone or in combination, to produce surgical analgesia at currently recommended dose rates and when reversal agents are given, analgesic effects are usually reversed as well as sedation. Thus, local anaesthetic blockade is still indicated, though the potential for drug or drug-metabolite residues in velvet antler remains a concern. The need for and effectiveness of non-steroidal anti-inflammatory drugs (NSAIDs) for post-operative analgesia requires investigation. Amitriptyline, locally administered opioid agonists, tramadol and other systemically administered agents may warrant future investigation for surgical and post-operative analgesia for velvet antler removal.

Enhanced initial bone regeneration with inorganic polyphosphate-adsorbed hydroxyapatite

Inorganic polyphosphate (poly(P)) can promote binding between fibroblast growth factors and their receptors and enhance osteoblastic cell differentiation and calcification. This study evaluated the possibilities for poly(P) adsorbed onto interconnected porous calcium hydroxyapatite (IP-CHA) as a new bone regeneration material. Prepared 1%, 5%, 25% and 50% poly(P)/IP-CHA composites showed the elution peak of poly(P) between 15 and 20 min, respectively, with the highest value from 50% poly(P)/IP-CHA in vitro. Histologically, at 1 week of placement into the femur of rabbits, granulation tissue had penetrated into the pores in all composites and IP-CHA as a control. In contrast, at 2 weeks of placement, newly formed lamellar bone was found in all groups, although a higher amount of bone regeneration was obviously formed in the 25% and 50% poly(P)/IP-CHA with a significantly higher value of bone regeneration ratio of 50% poly(P)/IP-CHA. These results indicate that 25% and 50% poly(P)/IP-CHA composites may enhance initial bone regeneration.

[What can we learn from the Scott Reuben case? Scientific misconduct in anaesthesiology]

In February 2009 a major case of scientific misconduct was discovered. The American pain researcher Dr. S. Reuben had published 21 papers over a period of 15 years that were found to be fraudulent. Suddenly many advances in postoperative pain therapy which had been assumed to be correct seemed questionable. In this review article the lessons which can be learnt from this case are described. This review also reveals that it is almost impossible for reviewers or readers of scientific journals to detect scientific fraud. However, several warning signs can be identified that might be useful when reading clinical papers. In retrospect many of these signs were detectable in Reuben's studies. Based on the fraudulent papers of Reuben it will be shown how and to what extent falsified results can affect other types of literature, such as practice guidelines, meta-analyses, review articles and oral presentations.

[Fraudulent pain research: a hurt so deep nothing can alleviate it]

Untruthfulness in research is reprehensible. Dr Scott S. Reuben, an anesthesiologist at Baystate Medical Center in Springfield, Massachusetts in the United States, a leader and pioneer in the field of multimodal analgesia, has been accused of fraud, specifically of having falsified results in at least 21 manuscripts published over a period of 15 years. This may come to be seen as one of the largest-scale and longest-running acts of medical research fraud ever. Apart from fabricated data, it seems the author committed other acts of misconduct. His coauthors have not been accused of wrongdoing, as they allege their names were falsely appended to the manuscript. The editors of the 2 most implicated journals, Anesthesiology and Anesthesia & Analgesia, have published editorials retracting the papers they judge to be fraudulent. Because Dr Reuben is a major figure in postoperative multimodal analgesia, many studies by other authors whose hypotheses have emerged from findings announced in the discredited papers may also now be considered contaminated by association. The definitions of scientific misconduct and the procedures for pursuing offenders vary greatly from country to country, creating a certain degree of uncertainty about how to proceed when we confront this problem. Beyond any possible legal liability that might arise, there are the questions of how fraud might affect patients' health or the medical knowledge base. Although the concept of multimodal analgesia may continue to be defended, we cannot be absolutely sure of its benefits without carrying out new clinical trials to repair the damage done by this act of misconduct.

Iliac crest reconstruction to reduce donor-site morbidity: technical note

The design of the study includes case series, technical note and review of the literature. Autogenous bone graft (autograft) harvest from the iliac crest remains the gold standard substrate for spinal fusion. Persistent donor-site pain is the most common cause of morbidity after autograft harvest, occurring in one-third of patients. Numerous techniques for reducing donor-site morbidity have been reported in the literature, including infusion of analgesics and post-harvest reconstruction of the iliac crest with ceramics, allograft or bone morphogenic protein. A case series of patients undergoing spinal fusion surgery is reported. All patients were treated with iliac crest reconstruction using Calcium Phosphate Cement and follow-up data of persistent donor-site pain was collected. Twelve patients underwent autograft harvest with iliac spine reconstruction using Calcium Phosphate Cement. 42% (5) had persistent donor-site pain (after 3 months). All pain scores were less than or equal to 2 out of 10 (mean 1.25). In conclusion, iliac spine reconstruction using Calcium Phosphate Cement following autogenous bone graft harvest is a relatively simple procedure which failed to decrease the incidence of donor-site morbidity in our patient population.

Continuous infusion of ropivacaïne: an optimal postoperative analgesia regimen for iliac crest bone graft in children

BACKGROUND

Postoperative analgesia of iliac crest (IC) donor site can be performed by on site infiltrations of local anesthetics (LA) or morphine. Single injections or continuous infusions of LA proved their efficacy in adults, but was not reported in children. We prospectively evaluated the interest of a continuous infusion of 0.2% ropivacaïne at the IC donor site in terms of postoperative pain relief and rescue analgesics consumption.

METHODS

Sixteen consecutive patients, aged from 4 to 16 years scheduled for maxillar alveolar graft with IC bone, were included. After IC bone graft surgery under general anesthesia, they received a 0.2-0.4 ml x kg(-1) bolus of 0.2% ropivacaïne through the IC catheter; then a continuous infusion of 0.2% ropivacaïne at 0.125 ml x kg(-1) x h(-1) was administrated for 48 h with disposable elastomeric pumps. Children systematically received paracetamol (15 mg x kg(-1) four times a day) and niflumic acid (40 mg x kg(-1) twice a day). Postoperative pain was evaluated using a Visual Analog Scale (>7 years old) or Children and Infants Postoperative Pain Score (between 4 and 7 years old) every 4 h until H48. Doses of rescue analgesics and adverse events (LA toxicity, catheter's removal, nausea-vomiting) were also noted. Three months after surgery a blinded clinical research assistant reviewed all children and assessed functional recovery, neuropathic chronic pain symptoms or local complications.

RESULTS

The median value of IC graft pain scores was 0 during whole studied period. Of the patients, 31.2% did not require any rescue analgesics and 43.8% needed only once. No adverse events related to LA and no removal of catheter were noted. One child had nausea in the 48-h postoperative period, and one child had neuropathic pain symptoms at 3 months at the donor site.

CONCLUSION

Continuous infusion of 0.2% ropivacaïne through an IC catheter is an optimal and safe technique of regional postoperative analgesia after bone graft harvest in children.

When pain after surgery doesn't go away…

Chronic post-surgical pain is a common, under-recognized and important clinical problem which affects millions of patients worldwide. It results from a series of neuroplastic changes associated most commonly with peripheral nerve injury at the time of surgery. Predisposing factors include the type of surgery, pre-operative and acute post-operative pain intensity, and probably psychological (e.g. pain-catastrophizing) and genetic factors [e.g. GCH1 (GTP cyclohydrolase 1) haplotype]. Preventive measures which are currently available include selection of a minimally invasive surgical technique and an aggressive multimodal perioperative analgesic regimen. Very promising therapeutic agents which target the sensitization process are currently in development.

[Pain therapy after spinal surgery]

A dorsal approach during spinal surgery offers the possibility to distribute drugs directly to the nerve root or epidurally. This can be done via a single intraoperative dose or by placing an epidural catheter. A safe and effective analgesia can thereby be achieved. As placement is done under visual control, no major complications are to be expected. In nerve root compressions, additional local application of steroids and preoperative gabapentin seems sensible. No advantage of preemptive administration of other analgesics can be determined. Another problem, especially of ventral fusions, is the commonly needed autologous pelvic bone grafts. Here the local application of local anesthetics or opioids makes sense. In transthoracic approaches epidural analgesia is recommended by thoracic surgeons, but this is difficult to perform especially in children with deformities. Furthermore it is generally important not to compromise neuralgic controls by analgesic measures.

Preventing the development of chronic pain after orthopaedic surgery with preventive multimodal analgesic techniques

The prevalences of complex regional pain syndrome, phantom limb pain, chronic donor-site pain, and persistent pain following total joint arthroplasty are alarmingly high. Central nervous system plasticity that occurs in response to tissue injury may contribute to the development of persistent postoperative pain. Many researchers have focused on methods to prevent central neuroplastic changes from occurring through the utilization of preemptive or preventive multimodal analgesic techniques. Multimodal analgesia allows a reduction in the doses of individual drugs for postoperative pain and thus a lower prevalence of opioid-related adverse events. The rationale for this strategy is the achievement of sufficient analgesia due to the additive effects of, or the synergistic effects between, different analgesics. Effective multimodal analgesic techniques include the use of nonsteroidal anti-inflammatory drugs, local anesthetics, alpha-2 agonists, ketamine, alpha(2)-delta ligands, and opioids.

Perioperative pain management

The under-treatment of postoperative pain has been recognised to delay patient recovery and discharge from hospital. Despite recognition of the importance of effective pain control, up to 70% of patients still complain of moderate to severe pain postoperatively. The mechanistic approach to pain management, based on current understanding of the peripheral and central mechanisms involved in nociceptive transmission, provides newer options for clinicians to manage pain effectively. In this article we review the rationale for a multimodal approach with combinations of analgesics from different classes and different sites of analgesic administration. The pharmacological options of commonly used analgesics, such as opioids, NSAIDs, paracetamol, tramadol and other non-opioid analgesics, and their combinations is discussed. These analgesics have been shown to provide effective pain relief and their combinations demonstrate a reduction in opioid consumption. The basis for using non-opioid analgesic adjuvants is to reduce opioid consumption and consequently alleviate opioid-related adverse effects. We review the evidence on the opioid-sparing effect of ketamine, clonidine, gabapentin and other novel analgesics in perioperative pain management. Most available data support the addition of these adjuvants to routine analgesic techniques to reduce the need for opioids and improve quality of analgesia by their synergistic effect. Local anaesthetic infiltration, epidural and other regional techniques are also used successfully to enhance perioperative analgesia after a variety of surgical procedures. The use of continuous perineural techniques that offer prolonged analgesia with local anaesthetic infusion has been extended to the care of patients beyond hospital discharge. The use of nonpharmacological options such as acupuncture, relaxation, music therapy, hypnosis and transcutaneous nerve stimulation as adjuvants to conventional analgesia should be considered and incorporated to achieve an effective and successful perioperative pain management regimen.

Chronic pain after surgery: What can we do to prevent it?

The development of chronic pain after surgery is not an uncommon event. Despite increased attention devoted to this topic in the recent medical literature, little is known about the underlying mechanisms, natural history, and response to therapy of each syndrome. Central nervous system plasticity that occurs in response to tissue injury may contribute to the development of persistent postsurgical pain. As evidence continues to accumulate concerning the role of central sensitization in the prolongation of postoperative pain, many researchers have focused on methods to prevent central neuroplastic changes from occurring through the use of preemptive or preventative analgesic techniques. Effective preventative analgesic techniques may be useful in reducing not only acute pain but also chronic postsurgical pain and disability. This review examines the efficacy of using a variety of analgesic techniques aimed at preventing or reducing chronic pain after surgery. Specific chronic postsurgical pain syndromes evaluated include complex regional pain syndrome, phantom limb pain, chronic donor site pain, post-thoracotomy pain syndrome, and postmastectomy pain syndrome.

Development of Cell-hybrid Artificial Bone: Effect of Osteogenic Differentiation of Bone Marrow Stromal Stem Cells on Bone Formation with Newly Developed Interconnected Porous Calcium Hydroxyapatite

The purpose of this study was to evaluate the effect of osteogenic differentiation of bone marrow stromal stem cells (BMSCs) on bone formation in a novel interconnected porous calcium hydroxyapatite (IP-CHA). BMSCs/IP-CHA composites, as a cell-hybrid artificial bone, were made by injecting BMSCs solution into IP-CHA scaffolds. To induce osteogenic differentiation, BMSCs/IP-CHA composites were subcultured for three, seven, 10, and 14 days. At the end of each subculture period, BMSCs/IP-CHA composites were examined by SEM and ALP staining. BMSCs/IP-CHA composites of different osteogenic groups of subculture were also placed into bone sockets in the right femur of beagle dogs. After four weeks, same placement procedure was done in the left femur. BMSCs/IP-CHA subcultured for 10 and 14 days were ALP-positive as opposed to those of three and seven days. At four weeks after placement, bone formation was superior at the 10- and 14-day subculture groups. Based on the results obtained, it was suggested that osteogenic differentiation periods with 10 and 14 days of subculture for BMSCs/IP-CHA as a cell-hybrid artificial bone were beneficial in promoting bone formation.

Anesthesia techniques in complex spine surgery

The safe performance of complex spine surgery requires the close collaboration of the anesthesiology and surgical teams. The avoidance of medical and anesthetic complications depends on the appropriate preoperative medical evaluation, patient positioning, selection and administration of anesthetic agents, management of intraoperative fluid status, emergence from anesthesia, and administration of postoperative analgesia.

Reconstruction of anterior iliac crest after bone graft harvest decreases pain: a randomized, controlled clinical trial

OBJECTIVE

A substantial number of patients report persistent pain after graft harvest from the anterior iliac crest. There have been several retrospective case series published that suggest that iliac crest reconstruction using a variety of techniques may decrease graft site pain. This study, a randomized, controlled clinical trial at a university hospital, tested the hypothesis that reconstruction of the iliac crest will reduce graft harvest site pain.

METHODS

A randomized, controlled clinical trial using the McGill Pain Inventory as the primary outcome measure was performed to evaluate the effect of anterior iliac crest reconstruction after graft harvest. Thirty patients who were treated with anterior cervical discectomy and fusion or cervical corpectomy and fusion with autologous iliac crest graft were randomized to one of two groups. Patients in Group 1 were treated with reconstruction of the iliac crest with commercially available tricalcium phosphate bone void filler after graft harvest. Patients in Group 2 were treated without graft site reconstruction. Graft site pain was assessed immediately after surgery, 6 weeks after surgery, and 3 months after surgery.

RESULTS

Treatment groups were well matched with regard to patient age, sex, and smoking history. Although patients in each group reported persistent pain 6 weeks and 3 months after graft harvest, patients in the reconstruction group reported significantly less severe pain at 6 weeks and tended to have less pain at 3 months after surgery.

CONCLUSION

Reconstruction of the iliac crest with tricalcium phosphate bone void filler significantly decreases the severity of postoperative pain 6 weeks after surgery.

[Potential applications and significance of peripheral opioid analgesia]

Recently, the local application of analgesic substances has attracted much interest and has become increasingly relevant in daily clinical practice. The lack of the well-known therapy-limiting central side effects of systemically administered opioids is a clear advantage of "peripheral opioid analgesia". Important prerequisites for the occurrence of peripheral analgesic effects of opioids are good accessibility of the painful site, presence of clinically relevant pain, signs of a local inflammation, exclusion of a fast systemic absorption, and adequately potent analgesic substances. This review gives an outline of recent experience with various clinical applications of "peripheral opioid analgesia".

Osteogenic potential of cultured bone/ceramic construct: comparison with marrow mesenchymal cell/ceramic composite

Osteogenesis occurs in porous hydroxyapatite (HA) when porous HA blocks combined with marrow mesenchymal cells are grafted in vivo. In vitro bone formation occurs in HA pores when HA combined with marrow cells is cultured in osteogenic medium containing dexamethasone. This cultured bone/HA construct possesses higher osteogenic ability when it is grafted in vivo. In the present study, we compared the osteogenic potential of a cultured bone/HA construct with that of a marrow mesenchymal cell/HA composite. Marrow cells were obtained from the femoral bone shaft of 7-week-old, male Fischer 344 rats and were cultured in T-75 flasks. Cells were concentrated, then frozen and stored in liquid nitrogen for 6 months. The cryopreserved cells were then thawed and prepared for subculture in porous HA (5 x 5 x 5 mm, Interpore 500) and for implantation with porous HA. After 2 weeks of subculture, three cultured bone/HA constructs were separately implanted in the right side of the back of each syngeneic 7-week-old male Fischer rat, and three thawed cell/HA composites (without subculture) were separately implanted in the left side. These implants were harvested at 2 or 4 weeks postimplantation, and prepared for histological, biochemical, and genetic analysis. Alkaline phosphatase activity and osteocalcin content of cultured bone/HA constructs were much higher than those of the cell/HA composites at 2 and 4 weeks postimplantation. Histological examination and gene expression data agreed with these findings. The culture technique discussed herein should facilitate the development of biosynthetic bone implants with higher osteogenic capacity.

A prospective, randomized, double-blind study evaluating the efficacy of postoperative continuous local anesthetic infusion at the iliac crest bone graft site after spinal arthrodesis

STUDY DESIGN

Parallel design, prospective, double-blind, randomized, controlled trial composed of two independent groups treated with a continuous infusion catheter (saline vs. Marcaine) placed into the iliac crest bone graft (ICBG) site.

OBJECTIVE

To determine the effects of postoperative continuous local anesthetic agent infusion at the ICBG harvest site in reducing pain, narcotic demand and usage, and improving early postoperative function after spinal fusion.

SUMMARY OF BACKGROUND DATA

Harvesting iliac crest bone has been shown to be a source of pain and morbidity. Long-term patient complaints may be more closely associated with the procurement of the iliac crest graft rather than the primary surgical site.

METHODS

Thirty-seven patients were enrolled in a prospective, randomized, double-blind parallel-designed study after informed consent and IRB approval was obtained. Twenty-eight patients had ICBG harvested for lumbar arthrodesis and nine for cervical arthrodesis. During spinal arthrodesis surgery, patients were randomly assigned to receive 96 mL (2 mL/hr x 48 hours) of either normal saline (control group, n = 22) or 0.5% Marcaine (treatment group, n = 15) delivered via a continuous infusion catheter placed at the ICBG harvest site. All patients received Dilaudid PCA after surgery. Pain scores, narcotic use/frequency, activity level, and length of stay (LOS) were recorded. Physicians, patients, nursing staff, and statisticians were blinded to the treatment.

RESULTS

Mean patient age was 60 years and similar between groups. Narcotic dosage, demand frequency, and mean VAS pain score were significantly less in the treatment (Marcaine) group at 24 and 48 hours (P < 0.05). The average LOS was 4.1 days with no difference between Marcaine or control groups. No complications were attributed to the infusion-catheter system.

CONCLUSIONS

Continuous infusion of 0.5% Marcaine at the ICBG harvest site reduced postoperative parenteral narcotic usage by 50% and decreased overall pain scores. No complications were attributed to the infusion-catheter system. The use of continuous local anesthetic infusion at the iliac crest may help in alleviating acute graft-related pain, hastening patient recovery and improving short-term satisfaction.

Can opioids prevent post-operative chronic pain?

Chronic post-operative pain is a major source of suffering and disability. Better standardisation for assessing and reporting chronic post-operative pain is needed. Peripheral and central nervous plasticity seem to play a major role in the development of chronic post-injury pain. Complex mechanisms, including several receptor systems and messenger systems are involved. Thus, it is unlikely that one single agent will solve the problem. Opioids have proven effect both in animal models, experimental human models, and in some clinical models. Timing and dose seem to be of importance. However, it is likely that polypharmacy and multi-modal treatment is necessary to further improve the preventive strategy.

Treatment of Pseudoarthrosis Using Tissue-Engineered Bone Graft

Subjects were graft patients with pseudoarthrosis (average age, 60.3 years; range, 17-85 years). Pseudoarthrosis affected the thoracolumbar spine, the femur, the clavicle, the humerus and the metatarsal. From the ilium (tibia in one patient), 10-20 ml of bone marrow fluid was collected, and then, it was immediately transferred to the culture room and incubated in a flask containing MEM with 15% autologous or fetal bovine serum, etc.. After 2 weeks in primary culture, cells were released by trypsin treatment and were subsequently incubated with porous beta-TCP in order to prepare tissue-engineered artificial bone, according to the previously reported modified culturing technique. Tissue-engineered artificial bone was grafted around the non-union site of each affected long bone, while tissue-engineered artificial bone was grafted via the pedicle of each affected vertebral body. In all patients, favorable bone formation was seen at three months after surgery. In the patients with pseudoarthrosis of the spine, CT and MRI confirmed favorable vertebral body formation. In the patients with pseudoarthrosis of a long bone, the artificial bone was remodeled and favorable bone union was confirmed. In 2 patients in whom bone biopsy was performed during pin removal, bone regeneration was confirmed histologically. With present type of tissue-engineered artificial bone, an artificial material with a high bone regeneration capacity can be prepared by aspiration, which is minimally invasive, and thus when compared to iliac bone grafts, it is possible to radically reduce postoperative pain without damage of autologous bone.

Peripheral opioid analgesia: Clinical applications

Peripheral opioid analgesia is undoubtedly of clinical relevance, especially considering that systemic opioid therapy often is hampered by central side effects. Despite some clinical studies that do not show peripheral opioid-mediated pain control, mostly because of methodologic shortcomings, studies evaluating inflammatory pain conditions show clear evidence and the number and the sites of applications are increasing. The intention of this paper is to give insight into the recent experience with the clinical applications of peripheral opioid analgesia.

Combined preemptive and preventive analgesia in morbidly obese patients undergoing open gastric bypass: A pilot study

PURPOSE

It is difficult to balance adequate pain control against the risk of sedation and depressed breathing in severely obese patients. This study assesses the effects of combined preemptive and preventive analgesia on narcotic use after open gastric bypass.

METHODS

Twenty patients were randomized in this prospective double-blind trial comparing preoperative 30 mg intravenous ketorolac (Toradol), 0.25% subcutaneous bupivacaine (Marcaine) with epinephrine along the planned incision, and 0.25% bupivacaine in the rectus fascia before closing with identical injections with 0.9% saline. The patients' self-assessed pain on a visual analogue scale (VAS) and total narcotic use by patient-controlled analgesia (PCA) and rescue medication were recorded.

RESULTS

Age, body mass index (BMI), incision length, and operative times were similar between the two groups, as was the average length of hospital stay (2.9 days). Self-reported pain was less in the treatment group 1 hour postoperatively (P = .01). Narcotic use was less in the treatment group during the first 2 hospital days (51% less on day 1 vs 44.5% less on day 2). Total narcotic use during the hospital stay was reduced by 40% (P = .02).

CONCLUSIONS

Patients receiving combined preemptive and preventive analgesia used significantly less narcotic pain medication than the patients receiving placebo. The effect lasted beyond the duration of action of the local anesthetic.