The development of postoperative knee chondrolysis after intra-articular pain pump infusion of an anesthetic medication: a series of twenty-one cases

Addition of Dexmedetomidine to Local Analgesia for Knee Arthroscopy

The search for the ideal pain management strategy after knee arthroscopy continues. For patients unable to receive regional anesthesia, peri-articular or intra-articular injections of local anesthetics with other medications offer a promising solution. Dexmedetomidine, (a short-term sedative analgesic marketed under the names Dexdor and Precedex), when added to local anesthetics, may offer an increase in the length of time between surgery and the need for a rescue analgesic agent. Whether the addition of dexmedetomidine results in lower pain scores or decreased opioid consumption remains to be proven. Systemic effects of dexmedetomidine, such as sedation and hypotension, appear less likely to occur with intra-articular injections, suggesting a favorable safety profile. The effects of dexmedetomidine on chondrocytes, as well as the effects of combining medications in the intra-articular environment, is less well understood and should be a focus of further research. Similarly, there is still a need to identify the best patients, best procedures, best combination of medications and best doses to optimize our approach to post-operative pain management via intra-articular injection.

FactFinders for patient safety: Preventing local anesthetic-related complications: Local anesthetic chondrotoxicity and stellate ganglion blocks

This series of FactFinders presents a brief summary of the evidence and outlines recommendations to improve our understanding and management of several potential local anesthetic-related complications. Evidence in support of the following facts is presented. (1) Chondrotoxicity: Which Local Anesthetics are Safest for Intraarticular Injection? -- There are drug-, concentration-, and time-dependent chondrotoxic effects that vary between local anesthetics. Current evidence related to commonly used local anesthetics indicates that with exposure to equivalent volumes, bupivacaine, at concentrations of 0.5 % or higher, is the most chondrotoxic agent, while ropivacaine, at concentrations equal to or less than 0.5 %, is the least chondrotoxic in vitro. There is minimal published evidence that confirms these findings in vivo. (2) Minimizing Risks with Stellate Ganglion Blocks -- Evidence suggests that fluoroscopic or ultrasound guidance reduces the risk and increases the accuracy of SGB. Utilizing ultrasound guidance has the added benefit of soft tissue visualization, especially vascular structures, which has the potential to prevent adverse outcomes when compared to the fluoroscopic technique.

Cytotoxicity of Local Anesthetics on Bone, Joint, and Muscle Tissues: A Narrative Review of the Current Literature

Background

Local anesthetics are commonly used in surgical procedures to control pain in patients. Whilst the cardiotoxicity and neurotoxicity of local anesthetics have received much attention, the cytotoxicity they exert against bone, joint, and muscle tissues has yet to be well recognized.

Objective

This review aimed to raise awareness regarding how local anesthetics may cause tissue damage and provide a deeper understanding of the mechanisms of local anesthetic-induced cytotoxicity. We summarized the latest progress on the cytotoxicity of local anesthetics and the underlying mechanisms and discussed potential strategies to reduce it.

Findings

We found that the toxic effects of local anesthetics on bone, joint, and muscle tissues were time- and concentration-dependent in vitro. Local anesthetics induced apoptosis, necrosis, and autophagy through specific cellular pathways. Altogether, this review indicates that toxicity of local anesthetics may be avoided by rationally selecting the appropriate anesthetic, limiting the total amount, and determining the lowest effective concentration and duration.

Liposomal Bupivacaine and Ropivacaine Adductor Canal Blocks for Anterior Cruciate Ligament Reconstruction Provide Similar Postoperative Analgesia

The purpose of this study was to compare postoperative pain following anterior cruciate ligament (ACL) reconstruction (ACLR) in patients receiving an adductor canal block (ACB) with ropivacaine (R-ACB) or liposomal bupivacaine (LB-ACB). The secondary purpose was to compare opioid consumption. A prospective cohort study of patients undergoing ACLR at an academic medical center was conducted from November 1, 2018 to November 21, 2019. The first cohort received R-ACB and 30 tablets of 5/325 mg oxycodone/acetaminophen. After June 13, 2019, the second cohort received LB-ACB and 20 tablets of 5/325 mg oxycodone/acetaminophen with the reduction in opioids prescribed resulting from a hospital quality improvement initiative to decrease narcotic consumption. From postoperative days 0 through 6, pain was assessed thrice daily using a numeric rating scale. Total postoperative opioid consumption was reported via tablet count and converted to oral morphine equivalents (OMEs). During this period, 165 subjects underwent ACLR, and 126 met the eligibility criteria (44.4% female, 55.6% male; mean ± standard deviation: 28.7 ± 13.7 years). Sixty-six (52.4%) received LB-ACB, and 60 (47.6%) received R-ACB (p = 0.53). The most common graft utilized was quadriceps autograft (63.6% LB-ACB; 58.3% R-ACB, p = 0.76). Mean postoperative pain scores were similar between groups during the entire postoperative period (p ≥ 0.08 for POD 0-6). While postoperative opioid consumption was lower among patients receiving LB-ACB (median OME [interquartile range]: 28.6 [7.5-63.8] vs. 45.0 [15.0-75.0], p = 0.023), this only amounted to an average of 2.2 tablets. Patients receiving LB-ACB in the setting of ACLR reported similar postoperative pain compared with those receiving R-ACB. Despite the second aim of our study, we cannot make conclusions about the effect of each block on opioid consumption given that each cohort received different numbers of opioid tablets due to institutional pressure to reduce opioid prescribing. As few patients completed their opioid prescriptions or requested refills, further reduction in prescription size is warranted. Future studies are necessary to further elucidate the effect of LB-ACB versus R-ACB on postoperative pain and opioid consumption after ACLR.

Accurate Reporting of Concomitant Procedures Is Highly Variable in Studies Investigating Knee Cartilage Restoration

OBJECTIVE

Successful clinical outcomes following cartilage restoration procedures are highly dependent on addressing concomitant pathology. The purpose of this study was to document methods for evaluating concomitant procedures of the knee when performed with articular cartilage restoration techniques, and to review their reported findings in high-impact clinical orthopedic studies. We hypothesized that there are substantial inconsistencies in reporting clinical outcomes associated with concomitant procedures relative to outcomes related to isolated cartilage repair.

DESIGN

A total of 133 clinical studies on articular cartilage repair of the knee were identified from 6 high-impact orthopedic journals between 2011 and 2017. Studies were included if they were primary research articles reporting clinical outcomes data following surgical treatment of articular cartilage lesions with a minimum sample size of 5 patients. Studies were excluded if they were review articles, meta-analyses, and articles reporting only nonclinical outcomes (e.g., imaging, histology). A full-text review was then used to evaluate details regarding study methodology and reporting on the following variables: primary cartilage repair procedure, and the utilization of concomitant procedures to address additional patient comorbidities, including malalignment, meniscus pathology, and ligamentous instability. Each study was additionally reviewed to document variation in clinical outcomes reporting in patients that had these comorbidities addressed at the time of surgery.

RESULTS

All studies reported on the type of primary cartilage repair procedure, with autologous chondrocyte implantation (ACI) noted in 43% of studies, microfracture (MF) reported in 16.5%, osteochondral allograft (OCA) in 15%, and osteochondral autograft transplant (OAT) in 8.2%. Regarding concomitant pathology, anterior cruciate ligament (ACL) reconstruction (24.8%) and meniscus repair (23.3%) were the most commonly addressed patient comorbidities. A total of 56 studies (42.1%) excluded patients with malalignment, meniscus injury, and ligamentous instability. For studies that addressed concomitant pathology, 72.7% reported clinical outcomes separately from the cohort treated with only cartilage repair. A total of 16.5% of studies neither excluded nor addressed concomitant pathologies. There was a significant amount of variation in the patient reported outcome scores used among the studies, with the majority of studies reporting International Knee Documentation Committee (IKDC) and Knee Injury and Osteoarthritis Outcomes Score (KOOS) in 47.2% and 43.6% of articles, respectively.

CONCLUSIONS

In this study on knee cartilage restoration, recognition and management of concomitant pathology is inadequately reported in approximately 28% of studies. Only 30% of articles reported adequate treatment of concomitant ailments while scoring their outcomes using one of a potential 18 different scoring systems. These findings highlight the need for more standardized methods to be applied in future research with regard to inclusion, exclusion, and scoring concomitant pathologies with regard to treatment of cartilage defects in the knee.

Combination of femoral triangle block and infiltration between the popliteal artery and the capsule of the posterior knee (iPACK) versus local infiltration analgesia for analgesia after anterior cruciate ligament reconstruction: a randomized controlled triple-blinded trial

BACKGROUND AND OBJECTIVES

Femoral triangle block and local infiltration analgesia are two effective analgesic techniques after anterior cruciate ligament reconstruction. Recently, the iPACK block (infiltration between the popliteal artery and the capsule of the posterior knee) has been described to relieve posterior knee pain. This randomized controlled triple-blinded trial tested the hypothesis that the combination of femoral triangle block and iPACK provides superior analgesia to local infiltration analgesia after anterior cruciate ligament reconstruction.

METHODS

Sixty patients undergoing anterior cruciate ligament reconstruction received general anesthesia and were randomly allocated to two groups: femoral triangle block and iPACK under ultrasound guidance or local infiltration analgesia. For each group, a total of 160 mg of ropivacaine was injected. Postoperative pain treatment followed a predefined protocol with intravenous morphine patient-controlled analgesia, acetaminophen, and ibuprofen. The primary outcome was cumulative intravenous morphine consumption at 24 hours postoperatively. Secondary pain-related outcomes included pain scores (Numeric Rating Scale out of 10) measured at 2 and 24 hours postoperatively. Functional outcomes, such as range of motion and quadriceps strength, were also recorded at 24 postoperative hours, and at 4 and 8 postoperative months.

RESULTS

Cumulative intravenous morphine consumption at 24 hours postoperatively was significantly reduced in the femoral triangle block and iPACK group (femoral triangle block and iPACK: 9.7 mg (95% CI: 6.7 to 12.7); local infiltration analgesia: 17.0 mg (95% CI: 11.1 to 23.0), p=0.03). Other pain-related and functional-related outcomes were similar between groups.

CONCLUSIONS

The combination of femoral triangle block and iPACK reduces intravenous morphine consumption during the first 24 hours after anterior cruciate ligament reconstruction, when compared with local infiltration analgesia, without effect on other pain-related, early, or late functional-related outcomes.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT03680716).

Effect of bupivacaine concentration and formulation on canine chondrocyte viability in vitro

OBJECTIVE

To quantitate bupivacaine concentration and formulation effects on chondrocyte viability in vitro.

STUDY DESIGN

Controlled laboratory study.

SAMPLE POPULATION

Primary canine chondrocyte isolates.

METHODS

Cell passage 3 and 4 canine chondrocytes were exposed to 0.9% saline; canine chondrocyte growth medium; 0.4, 0.5, 0.6, 1.5, 2.5, 3.5, or 5 mg/mL preservative-free standard formulation bupivacaine (SFB); or 13.3 or 6.65 mg/mL liposomal encapsulated bupivacaine (LEB) for 1 hour. Chondrocyte viability and clonogenicity were quantitated with 3-(4,5-dimethylthiazol-2-31 yl)-2,5-diphenyltetrazolium bromide (MTT) and clonogenic assays, respectively. Differences among concentrations and formulations were assessed with Kruskal-Wallis and Dwass-Steel-Critchlow-Fligner post hoc tests.

RESULTS

Growth medium had the highest cell viability based on MTT metabolism. Similarly, all LEB concentration groups had higher cell viability compared with SFB concentration cells treated with 3.5 or 5 mg/mL SFB (P < .03). Among SFB concentrations, cell viability was higher at 0.6 mg/mL compared with at 2.5 mg/mL or greater (P < .03). Cell clonogenicity was not significantly different between saline, culture medium, or 0.5 mg/mL SFB. Clonogenicity was lower with all tested LEB concentrations compared with saline or medium (P < .02).

CONCLUSION

In vitro toxicity of SFB on canine chondrocytes is concentration dependent. Liposomal encapsulated bupivacaine may have time-dependent effects resulting in chondrotoxicity.

CLINICAL SIGNIFICANCE

Clinically relevant concentrations of SFB after a single injection may not result in chondrotoxic effects in vitro. Liposomal encapsulated bupivacaine should not be used in the articular environment.

Risk Factors for Rapid Chondrolysis After Partial Lateral Meniscectomy: A Scoping Review of the Literature

Background

The occurrence of rapid chondrolysis after partial lateral meniscectomy is rare. The pathophysiology, risk factors, and outcomes of treatment have not been established.

Purpose

The primary aim of this study was to perform a scoping review of the literature to determine the potential risk factors and pathogenesis of rapid chondrolysis. The secondary objective was to report outcomes of treatment.

Study Design

Systematic (scoping) review.

Methods

A scoping review of the literature was conducted in accordance with the framework of Arksey and O'Malley. A search strategy based on the terms "chondrolysis" AND "knee," "chondrolysis" AND "meniscus," and "chondral damage" AND "lateral meniscus" was applied to the PubMed database on March 31, 2020. All relevant studies were included. Patient demographics and clinical data were extracted from these studies and analyzed in order to investigate the potential risk factors, pathogenesis, and outcomes of treatment for rapid chondrolysis.

Results

Five articles (22 cases) featuring rapid chondrolysis in the lateral compartment after partial lateral meniscectomy were identified and included. The condition occurred most frequently in patients who were young (mean age, 25.6 years), male (20/22 cases; 91%), and participating in high-intensity sports (19/22 cases; 86.4%) within 1 year of the index procedure. Half of the included study population underwent surgery for a radial tear. All professional athletes (13/13) returned to the preinjury level of sport. All authors of included studies suggested that the main causal risk factor was mechanical focal cartilage overload in the lateral compartment of the knee.

Conclusion

Rapid chondrolysis after partial lateral meniscectomy is a rare condition that typically occurs within 12 months of the index procedure. Younger age, male sex, high-intensity sports participation, and some meniscal tear patterns (eg, radial tear) are potentially important risk factors. Return-to-sport rates at short-term follow up are high, but no long-term studies were identified. The pathogenesis of rapid chondrolysis seems to relate to mechanical focal cartilage overload.

Intra-articular infiltration analgesia for arthroscopic shoulder surgery: a systematic review and meta-analysis

Phrenic-sparing analgesic techniques for shoulder surgery are desirable. Intra-articular infiltration analgesia is one promising phrenic-sparing modality, but its role remains unclear because of conflicting evidence of analgesic efficacy and theoretical concerns regarding chondrotoxicity. This systematic review and meta-analysis evaluated the benefits and risks of intra-articular infiltration in arthroscopic shoulder surgery compared with systemic analgesia or interscalene brachial plexus block. We sought randomised controlled trials comparing intra-articular infiltration with interscalene brachial plexus block or systemic analgesia (control). Cumulative 24-h postoperative oral morphine equivalent consumption was designated as the primary outcome. Secondary outcomes included visual analogue scale pain scores during the first 24 h postoperatively; time-to-first analgesic request; patient satisfaction; opioid-related side-effects; block-related adverse events; and any indicators of chondrotoxicity. Fifteen trials (863 patients) were included. Compared with control, intra-articular infiltration reduced 24-h postoperative analgesic consumption by a weighted mean difference (95%CI) of -30.9 ([-38.9 to -22.9]; p < 0.001). Intra-articular infiltration also reduced the weighted mean difference (95%CI) pain scores up to 12 h postoperatively, with the greatest reduction at 4 h (-2.2 cm [(-4.4 to -0.04]); p < 0.05). Compared with interscalene brachial plexus block, there was no difference in opioid consumption, but patients receiving interscalene brachial plexus block had better pain scores at 2, 4 and 24 h postoperatively. There was no difference in opioid- or block-related adverse events, and none of the trials reported chondrotoxic effects. Compared with systemic analgesia, intra-articular infiltration provides superior pain control, reduces opioid consumption and enhances patient satisfaction, but it may be inferior to interscalene brachial plexus block patients having arthroscopic shoulder surgery.

Continuous Wound Infiltration of Local Anesthetics in Postoperative Pain Management: Safety, Efficacy and Current Perspectives

Local infiltration and continuous infusion of surgical wound with anesthetics are parts of multimodal analgesia for postoperative pain control. The techniques, given the simplicity of execution that does not increase the timing of the intervention and does not require additional technical skills, are applied in several kinds of surgeries. The continuous wound infiltration can be used for days and a variety of continuous delivery methods can be chosen, including patient-controlled analgesia, continuous infusion or intermittent bolus. The purpose of this narrative review is to analyze the literature, in particular by researching the safety, efficacy and current perspectives of continuous wound infiltration for postoperative pain management in different surgical settings. We have identified 203 articles and 95 of these have been taken into consideration: 17 for the lower limb surgery; 7 for the upper limb surgery, 51 for the laparotomy/laparoscopic surgery of the abdominopelvic area, 13 studies regarding breast surgery and 7 for cardiothoracic surgery. The analysis of these studies reveals that the technique has a variable effectiveness based on the type of structure involved: it is better in structures rich in subcutaneous and connective tissue, while the effectiveness is limited in anatomic districts with a greater variability of innervation. However, regardless the heterogeneity of results, a general reduction in pain intensity and in opioid consumption has been observed with continuous wound infiltration: it is an excellent analgesic technique that can be included in the multimodal treatment of postoperative pain or represents a valid alternative when other options are contraindicated.

Adductor canal block versus local infiltration analgesia for postoperative pain after anterior cruciate ligament reconstruction: a single centre randomised controlled triple-blinded trial

BACKGROUND

Both the adductor canal block (ACB) and local infiltration analgesia (LIA) are effective analgesic techniques after anterior cruciate ligament (ACL) reconstruction, but they have never been compared head-to-head. This randomised controlled triple-blinded trial tested the hypothesis that ACB provides superior analgesia to LIA after ACL reconstruction, with additional focus on postoperative functional outcomes.

METHODS

Of 104 enrolled ACL reconstruction patients receiving general anaesthesia, 52 were randomly allocated to either ACB under ultrasound guidance or LIA. For each intervention, ropivacaine 0.5%, 20 ml was injected. Postoperative pain treatment followed a predefined protocol with i.v. patient-controlled morphine, paracetamol, and ibuprofen. The primary outcome was cumulative i.v. morphine consumption at 24 h after operation. Secondary pain-related outcomes included resting and dynamic pain scores (numeric rating scale out of 10) measured 2, 24, and 48 h after operation and cumulative i.v. morphine consumption 2 and 48 h after operation. Early function-related outcomes evaluated were quadriceps strength, walking distance, and range of motion, all measured 24 and 48 h after operation. Late function-related outcomes were concentric quadriceps strength, single-hop test, triple-hop test, cross-over test, and Y balance test, measured at 4 and 8 postoperative months.

RESULTS

Cumulative i.v. morphine consumption at 24 h was similar between groups (ACB group: 17.1 mg [95% confidence interval, CI: 13.1, 21.2]; LIA group: 17.7 mg [95% CI: 13.2, 22.6], P=0.84). Similarly, no differences between groups were seen in the secondary pain- or function-related outcomes.

CONCLUSIONS

ACB and LIA result in equivalent postoperative opioid consumption with similar impact on postoperative pain scores and functional outcomes.

CLINICAL TRIAL REGISTRATION

NCT02524652.

Single-dose local anesthetics exhibit a type-, dose-, and time-dependent chondrotoxic effect on chondrocytes and cartilage: a systematic review of the current literature

PURPOSE

Many studies have shown that local anesthetics may impede chondrocyte metabolism. However, the influence of a single-dose local anesthetics is controversial. The aim of this metaanalysis was to review the literature for studies investigating the cytotoxic effects of single-dose local anesthetics on chondrocytes and cartilage.

METHODS

A comprehensive literature search was performed using established search engines (Medline, Embase) to identify studies, investigating the influence of single-dose local anesthetics on cartilage. The systematic analysis included the influence on histology, cell viability, morphology, and matrix production depending upon dose, exposure time, and type of local anesthetics.

RESULTS

Twelve studies with four different local anesthetics were included in this metaanalysis. Bupivacaine and lidocaine were found to be more chondrotoxic than mepivacaine and ropivacaine. The amount of dead cells increased in a substance-, dose-, and time-dependent process. Osteoarthritic cartilage seems to be more vulnerable compared to intact cartilage. The toxic effects occur first in the superficial cartilage layers and include damage to membrane integrity, mitochondrial DNA, and nuclear changes. There is no study that could show a significant chondrotoxic effect with low concentrations of bupivacaine (0.0625%), ropivacaine (0.1 and 0.2%), and mepivacaine (0.5%).

CONCLUSIONS

The cytotoxicity of local anesthetics on chondrocytes is dependent on dose, time, and type of local anesthetics. Single-dose intra-articular administration of local anesthetics impede chondrocyte metabolism and should be performed only with low concentrations for selected diagnostic purposes and painful joints. The use of lidocaine should be avoided.

LEVEL OF EVIDENCE

II.

Continuous Wound Infiltration After Hallux Valgus Surgery

BACKGROUND

Hallux valgus surgery is associated with significant early postoperative pain. The aim of this study was to investigate the use of continuous wound infiltration (CWI) with ropivacaine for pain management after hallux valgus surgery.

METHODS

In this prospective, randomized, double-blind, and placebo-controlled single-center trial, 50 patients undergoing distal metatarsal osteotomy for idiopathic hallux valgus were allocated to CWI with ropivacaine 2 mg/mL at a rate of 2 mL/h or placebo for 24 hours postoperatively. Average and peak pain levels on the verbal numeric rating scale (NRS; 1-10) during the first 48 hours after surgery were recorded as primary outcome parameters. Secondary outcome parameters included consumption of narcotics, clinical outcome, incidence of postoperative complications, and patient satisfaction.

RESULTS

No significant difference in mean ( P = .596) and peak ( P = .353) postoperative pain level was found for CWI with either ropivacaine (mean NRS 1.9 ± 0.8; peak NRS 3.5 ± 2.0) or placebo (mean NRS 2.0 ± 0.7; peak NRS 3.9 ± 1.7) during the early postoperative course. Furthermore, no significant difference between both groups was detected regarding narcotic consumption ( P = .354) and all other secondary outcome parameters. Two severe complications (local dysesthesia with CWI, catheter accidentally fixed by a suture) and 5 catheter dislocations were observed.

CONCLUSION

CWI with ropivacaine 2 mg/mL at a rate of 2 mL/h for 24 hours after hallux valgus surgery did not reduce postoperative pain level in an inpatient setting.

LEVEL OF EVIDENCE

Level I, prospective randomized trial.

Use of the On-Q Pain Pump in Alveolar Bone Grafting: Effect on Hospit Length of Stay

Objective

Alveolar bone grafting (ABG) with iliac crest bone graft can be associated with significant pain at the donor site. The On-Q pain pump has been shown to be efficacious in treating postsurgical pain. The aim of this study was to compare the length of postoperative hospital stay in patients undergoing ABG who received the On-Q pain pump at the iliac crest donor site (On-Q+) with that of patients who did not receive the On-Q pain pump (On-Q-).

Design

A retrospective, cohort study, approved by institutional review board, was performed. Thirty-one consecutive patients in the On-Q- group were compared with 38 consecutive patients in the On-Q– group. The two cohorts were assessed for length of stay. Statistical analysis was performed using the Fisher exact probability test.

Setting

Tertiary care academic medical center.

Patients

Sixty-nine patients with cleft lip and/or cleft palate (CL/P) undergoing secondary ABG with iliac crest bone graft were operated on between May 1993 and January 2014.

Main Outcome Measure

Length of postoperative hospital stay.

Result

Mean length of stay in the On-Q– patients was 0.52 days versus 0.37 days for the On-Q– patients. This difference between the two cohorts was not statistically significant (P = .234).

Conclusion

Although there is a trend toward a shorter length of stay in our patients who received the On-Q pump, this finding was not statistically significant. Given the expense and additional burden of care associated with the device, we have become more selective in its utilization.

Improved Chondrotoxic Profile of Liposomal Bupivacaine Compared With Standard Bupivacaine After Intra-articular Infiltration in a Porcine Model

BACKGROUND

Increasingly, liposomal bupivacaine is being used with multimodal pain management strategies. In vitro investigations have shown decreased chondrotoxicity profiles for liposomal bupivacaine; however, there is no evidence regarding its in vivo effects. Hypothesis/Purpose: This study sought to investigate the in vivo chondrotoxicity of liposomal bupivacaine, hypothesizing that there would be increased chondrocyte viability after exposure to liposomal bupivacaine when compared with standard bupivacaine.

STUDY DESIGN

Controlled laboratory study.

METHODS

Eight juvenile, female Yorkshire cross piglets underwent a lateral stifle joint injection with either 1.3% liposomal bupivacaine or 0.5% bupivacaine. Injections were performed on one joint per animal with no injection to the contralateral knee, which served as the control. Chondrocyte viability was assessed 1 week after injection with a live-dead staining protocol and histologic examination.

RESULTS

Significant chondrocyte death was seen with the live-dead staining in the bupivacaine group (33% nonviable cells) in comparison with liposomal bupivacaine (6.2%) and control (5.8%) groups ( P < .01). However, histologic examination showed no differences in chondral surface integrity, fibrillation, and chondrocyte viability.

CONCLUSION

Liposomal bupivacaine was found to be safe for intra-articular injection in this animal model. Although bupivacaine demonstrated decreased chondrocyte viability on a cellular level, histologically there were no changes. This study highlights the dichotomy between fluorescent staining and histologic appearance of articular chondrocytes in short-term analyses of viability.

CLINICAL RELEVANCE

This study supports the peri-articular application of liposomal bupivacaine in the setting of preserved articular cartilage. A single injection of standard bupivacaine did not produce histologic changes in the articular cartilage.

Pain Management After Outpatient Anterior Cruciate Ligament Reconstruction: A Systematic Review of Randomized Controlled Trials

BACKGROUND

Effective pain management after anterior cruciate ligament (ACL) reconstruction improves patient satisfaction and function.

PURPOSE

To collect and evaluate the available evidence from randomized controlled trials (RCTs) on pain control after ACL reconstruction.

STUDY DESIGN

Systematic review.

METHODS

A systematic literature review was performed using PubMed, Medline, Google Scholar, UpToDate, Cochrane Reviews, CINAHL, and Scopus following PRISMA guidelines (July 2014). Only RCTs comparing a method of postoperative pain control to another method or placebo were included.

RESULTS

A total of 77 RCTs met inclusion criteria: 14 on regional nerve blocks, 21 on intra-articular injections, 4 on intramuscular/intravenous injections, 12 on multimodal regimens, 6 on oral medications, 10 on cryotherapy/compression, 6 on mobilization, and 5 on intraoperative techniques. Single-injection femoral nerve blocks provided superior analgesia to placebo for up to 24 hours postoperatively; however, this also resulted in a quadriceps motor deficit. Indwelling femoral catheters utilized for 2 days postoperatively provided superior analgesia to a single-injection femoral nerve block. Local anesthetic injections at the surgical wound site or intra-articularly provided equivalent analgesia to regional nerve blocks. Continuous-infusion catheters of a local anesthetic provided adequate pain relief but have been shown to cause chondrolysis. Cryotherapy improved analgesia compared to no cryotherapy in 4 trials, while in 4 trials, ice water and water at room temperature provided equivalent analgesic effects. Early weightbearing decreased pain compared to delayed weightbearing. Oral gabapentin given preoperatively and oral zolpidem given for the first week postoperatively each decreased opioid consumption as compared to placebo. Ibuprofen reduced pain compared to acetaminophen. Oral ketorolac reduced pain compared to hydrocodone-acetaminophen.

CONCLUSION

Regional nerve blocks and intra-articular injections are both effective forms of analgesia. Cryotherapy-compression appears to be beneficial, provided that intra-articular temperatures are sufficiently decreased. Early mobilization reduces pain symptoms. Gabapentin, zolpidem, ketorolac, and ibuprofen decrease opioid consumption. Despite the vast amount of high-quality evidence on this topic, further research is needed to determine the optimal multimodal approach that can maximize recovery while minimizing pain and opioid consumption.

CLINICAL RELEVANCE

These results provide the best available evidence from RCTs on pain control regimens after ACL reconstruction.

Gonyautoxins: First evidence in pain management in total knee arthroplasty

Improvements in pain management techniques in the last decade have had a major impact on the practice of total knee arthroplasty (TKA). Gonyautoxin are phycotoxins, whose molecular mechanism of action is a reversible block of the voltage-gated sodium channels at the axonal level, impeding nerve impulse propagation. This study was designed to evaluate the clinical efficacy of Gonyautoxin infiltration, as a long acting pain blocker in TKA. Fifteen patients received a total dose of 40 μg of Gonyautoxin during the TKA operation. Postoperatively, all patients were given a standard painkiller protocol: 100 mg of intravenous ketoprofen and 1000 mg of oral acetaminophen every 8 hours for 3 days. The Visual Analog Scale (VAS) pain score and range of motion were recorded 12, 36, and 60 hours post-surgery. All patients reported pain of 2 or less on the VAS 12 and 36 hours post-surgery. Moreover, all scored were less than 4 at 60 hours post-surgery. All patients achieved full knee extension at all times. No side effects or adverse reactions to Gonyautoxin were detected in the follow-up period. The median hospital stay was 3 days. For the first time, this study has shown the effect of blocking the neuronal transmission of pain by locally infiltrating Gonyautoxin during TKA. All patients successfully responded to the pain control. The Gonyautoxin infiltration was safe and effective, and patients experienced pain relief without the use of opioids.

[Muscle, tendon and joint injections : What is the evidence?]

Injections at tendon insertions, in muscles and in joints are an important instrument in the conservative treatment of musculoskeletal diseases, for acute injuries as well as for chronic degenerative diseases. Local anesthetic agents and glucocorticoids are well-established medications; however, severe side effects, such as chondrolysis have sometimes been reported, particularly for local anesthetic agents. In addition platelet rich plasma (PRP) and hyaluronic acid are also widely used; however, the clinical effectiveness has not always been proven. This article gives an overview on the most commonly used medications for injections and the mechanisms of action. The indications for treatment and the evidence for the clinical adminstration of muscle, tendon and joint injections are described based on the currently available literature.

Rapid chondrolysis of the medial knee compartment after arthroscopic meniscal resection: a case report

Background

Rapidly destructive osteoarthritis of the hip and rapid chondrolysis of the lateral compartment of the knee or the shoulder are rare, but have been previously described in the medical literature. To the best of our knowledge, no case of medial femorotibial compartment chondrolysis after arthroscopy has yet been described. We therefore submit the first case report.

Case presentation

A 64-year-old white European man presented with right knee pain due to a medial meniscal tear with no other abnormality found on examination or imaging. An arthroscopic partial medial meniscectomy was performed and early evolution was favorable with no signs of infection. He developed knee pain 2 months later. X-rays showed a thinning of the medial compartment which was confirmed by computed tomography arthrogram. There was no articular effusion, mobility was conserved (0/0/125°), there was no laxity, and pain was localized to the medial femorotibial compartment, with no meniscal signs. There was a 8° varus deviation (versus 3° for his uninjured left knee). His blood work was normal. As there were no signs of infection, no aspiration was performed. Viscosupplementation was offered but refused by the patient. He is now waiting for a partial knee replacement.

Conclusions

To the best of our knowledge, this is the first description of such a case. Rapid chondrolysis has been described in the hip, shoulder, and the lateral compartment of the knee. Infiltration of bupivacaine and lateral meniscectomy are the most frequently sited offending procedures. Concerning the medial compartment, cases of avascular necrosis have been reported after meniscectomy or use of radiofrequency devices. This case underlines the necessity of a thorough physical examination and complete radiological work up before any surgery. It must also drive us to use caution regarding meniscectomy, especially in patients over 60 years of age, and reminds us that patients must be informed of this potential complication.

Common contra-indications and interactions of drugs in orthopaedic practice

Drug therapy forms an integral part of the management of many orthopaedic conditions. However, many medicines can produce serious adverse reactions if prescribed inappropriately, either alone or in combination with other drugs. Often these hazards are not appreciated. In response to this, the European Union recently issued legislation regarding safety measures which member states must adopt to minimise the risk of errors of medication. In March 2014 the Medicines and Healthcare products Regulatory Agency and NHS England released a Patient Safety Alert initiative focussed on errors of medication. There have been similar initiatives in the United States under the auspices of The National Coordinating Council for Medication Error and The Joint Commission on the Accreditation of Healthcare Organizations. These initiatives have highlighted the importance of informing and educating clinicians. Here, we discuss common drug interactions and contra-indications in orthopaedic practice. This is germane to safe and effective clinical care.

Knee chondrolysis by infusion of bupivacaine with epinephrine through an intra-articular pain pump catheter after arthroscopic ACL reconstruction

BACKGROUND

Postoperative knee chondrolysis caused by continuous intra-articular pain pumps infusing bupivacaine with epinephrine is a rare but serious complication.

PURPOSE

To determine the association between postoperative intra-articular infusion of bupivacaine with epinephrine and the development of knee chondrolysis in patients who have undergone arthroscopic anterior cruciate ligament reconstruction (ACLR). The authors hypothesized that the development of knee chondrolysis after ACLR is associated with postoperative high-dose intra-articular bupivacaine with epinephrine infusion.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

In this retrospective cohort study, the charts of all patients treated with arthroscopic ACLR by a single surgeon between January 1, 2004, and December 31, 2006, were reviewed. Patients with severe articular cartilage damage at the time of the index procedure, with known knee joint infection, inflammatory arthritis, multiligament knee injury, bilateral knee injury, or any previous knee surgery, were excluded. Patients were grouped into 2 cohorts: the exposure group (those who had postoperative infusion of bupivacaine with epinephrine via an intra-articular pain pump [IAPP]) and the nonexposure group (those without postoperative infusion).

RESULTS

A total of 105 patients met the inclusion and exclusion criteria. There were 57 male and 48 female patients with a mean age at surgery of 25.5 ± 8.6 years (range, 13-52 years). The exposure group consisted of 46 patients and the control group of 59 patients. Thirteen of 46 patients (28.3%) who received an IAPP developed chondrolysis. There were no cases of chondrolysis in the control group. Of those in the exposure group, 32 patients were exposed to 0.5% bupivacaine with epinephrine and 12 developed chondrolysis (37.5%), while 14 patients were exposed to 0.25% bupivacaine with epinephrine and 1 developed chondrolysis (7.1%). Patients exposed to 0.5% bupivacaine with epinephrine had a significantly higher incidence of chondrolysis compared with those exposed to 0.25% (P = .03). Patients with chondrolysis had severe pain and limitations in daily activity.

CONCLUSION

The development of knee chondrolysis was associated with the intra-articular infusion of bupivacaine with epinephrine postoperatively. Furthermore, the presented evidence suggests that this occurs in a dose-dependent manner. The risk of knee chondrolysis might be reduced by avoidance of intra-articular infusion of bupivacaine with epinephrine. We recommend against continuous intra-articular infusion of local anesthetic postoperatively.

Efficacy of periarticular multimodal drug injection after medial opening-wedge high tibial osteotomy: a randomized, controlled study

PURPOSE

The purpose of this study was to evaluate the efficacy of periarticular multimodal drug injection after medial opening-wedge high tibial osteotomy regarding the postoperative pain level.

METHODS

From January 2011 to January 2012, 70 patients underwent medial opening-wedge high tibial osteotomy. Thirty-five patients were randomly assigned to receive no injection (group I), and 35 patients were assigned to receive periarticular multimodal drug injection (group II). These 2 groups were compared regarding the postoperative pain level, frequency of additional nonsteroidal anti-inflammatory drug injections, total amount of patient-controlled analgesia, and number of times that patients pushed the patient-controlled analgesia button at each time interval. Statistical results were based on multivariate analysis of variance and repeated-measures analyses.

RESULTS

Multivariate analysis of variance of mean visual analog scale (VAS) scores over the 2-week postoperative period showed statistical significance (P < .001). Repeated-measures analysis yielded a statistically significant difference (P = .001) for the time-by-treatment interaction, showing a clear periarticular multimodal drug injection benefit over time based on VAS scores. In addition, the mean number of times that patients pushed the patient-controlled analgesia button differed significantly between groups over time (P = .01). The VAS scores, frequency of additional nonsteroidal anti-inflammatory drug injections, mean number of times that patients pushed the patient-controlled analgesia button, and mean total amount of fentanyl consumption differed significantly within each group over time (P < .001 for all variables). However, the frequency of additional nonsteroidal anti-inflammatory drug injections and mean total amount of fentanyl consumption did not differ significantly between groups over time (P = .822, P = .529, and P = .282). Opioid- and injection-related complications were not found.

CONCLUSIONS

This prospective randomized study shows that intraoperative periarticular multimodal drug injections in patients undergoing medial opening-wedge high tibial osteotomy for unicompartmental osteoarthritis of the knee could result in significant reductions in VAS scores at 2 weeks postoperatively.

LEVEL OF EVIDENCE

Level I, high-quality randomized controlled trial with statistically significant differences.

Approach to pain management in chronic opioid users undergoing orthopaedic surgery

Opioids are commonly used for the management of pain in patients with musculoskeletal disorders; however, national attention has highlighted the potential adverse effects of the use of opioid analgesia in this and other nonmalignant pain settings. Chronic opioid users undergoing orthopaedic surgery represent a particularly challenging patient population in regard to their perioperative pain control and outcomes. Preoperative evaluation provides an opportunity to estimate a patient's preoperative opioid intake, discuss pain-related fears, and identify potential psychiatric comorbidities. Patients using high levels of opioids may also require referral to an addiction specialist. Various regional blockade and pharmaceutical options are available to help control perioperative pain, and a multimodal pain management approach may be of particular benefit in chronic opioid users undergoing orthopaedic surgery.

Rapid chondrolysis following an unoperated lateral meniscus tear in a young professional rugby player

Rapid chondrolysis following a lateral meniscectomy is a rare complication. We present the first reported case of rapid chondrolysis of the lateral compartment, which developed 6 months after a meniscus tear that was not surgically treated in a young 18-year-old professional rugby player. The possible hypotheses to explain this complication are presented, and certain previously published causes were excluded (iatrogenic during surgery, undiagnosed increased rotatory instability, chondrotoxicity of bupivacaine). Overloading of the cartilage surface of the lateral compartment from meniscal extrusion can cause cartilage necrosis.

Effect of intra-articular local anesthesia on articular cartilage in the knee

PURPOSE

To evaluate the hypothetical toxic effect of local anesthetics on the articular cartilage using patient data from autologous chondrocyte cultivation with different anesthesia types used for arthroscopic cartilage biopsy specimen procurement.

METHODS

A retrospective analysis of patient data from the national autologous chondrocyte implantation registry and the corresponding hospital records was approved by the National Medical Ethics Committee. Articular cartilage biopsy specimens from the knees of 49 consecutive patients assigned for autologous chondrocyte implantation (aged 14 to 44 years) were procured from the non-weight-bearing articular surface during arthroscopy under general anesthesia (12 patients), spinal anesthesia (18 patients), or local anesthesia (intra-articular injection of 15 to 20 mL of 2% lidocaine hydrochloride) (19 patients). All the biopsy specimens were further manipulated following the same chondrocyte cultivation protocol. General patient data and surgery-related parameters, together with chondrocyte viability, population doublings, and chondrocyte morphology in biopsy specimens and primary cell cultures, were analyzed and compared across different types of anesthesia.

RESULTS

Patients in the general, spinal, and local anesthesia groups showed no statistical differences in age (27 years, 29 years, and 32 years, respectively), duration of surgery (36 minutes, 37 minutes, and 39 minutes, respectively), weight of biopsy specimens (110 mg, 178 mg, and 130 mg, respectively), cell viability in cartilage biopsy specimens (67%, 69%, and 78%, respectively) or primary cultures (95%, 95%, and 95%, respectively), and population doublings (5.2, 5.2, and 5.2, respectively). Similar chondrocyte morphology in primary cell cultures was observed among the 3 groups.

CONCLUSIONS

This retrospective study showed that a single intra-articular injection of lidocaine hydrochloride used for knee arthroscopy did not influence the viability, morphology, and cultivation potential of chondrocytes in articular cartilage biopsy specimens assigned for autologous chondrocyte implantation.

LEVEL OF EVIDENCE

Level IV, retrospective comparative study.

Intra-articular lidocaine for reduction of shoulder dislocation

Anterior shoulder dislocation is the most common joint dislocation seen in the emergency department. Although emergency medicine providers use several techniques for reduction, each method is associated with potential discomfort for the patient. In addition, pain from the dislocated shoulder causes muscle spasm that impedes reduction. Therefore, both analgesia and procedural sedation are often used to reduce pain and enable reduction. Intra-articular injection of lidocaine has demonstrated efficacy in reduction of pain and facilitation of shoulder reduction compared with analgesia and sedation. Intra-articular lidocaine may also reduce time to successful reduction of shoulder dislocations.

[Update on the pharmacology and effects of local anesthetics]

Local anesthetics (LA) are broadly used in all disciplines and it could be considered that relatively little is reflected on the mechanisms of action of this old substance group. However, several molecular mechanisms of LAs mediating wanted and unwanted effects remain to be explored. Furthermore, the number of indications for application of LAs seems to be expanding. The local anesthetic effect of LAs is primarily mediated by a potent inhibition of voltage-gated sodium channels. However, this effect is due to much more than the interaction of LAs with one single molecule. Most recent studies indicated that the development of selective local anesthetics might be possible and LAs also interact with several other membrane molecules. Although the relevance of these effects is still unclear, they might play a role in systemic analgesia, tissue protection and anti-inflammatory effects of LA. The therapeutic index of systemically applied LA is very narrow. Systemic application is formally not permitted because the impending systemic toxicity is still a life-threatening complication. Although the cardiac and central nervous toxicity at least partly result from an unselective block of neuronal and cardiac sodium channels, preclinical studies suggest the involvement of several mechanisms. A local LA toxicity is less clinically impressive; however, all LAs induce a significant tissue toxicity for which the underlying mechanisms have been partly identified. This review reports on recent findings on mechanisms and on the clinical relevance of some LA-induced effects which are of relevance for anesthesiological activities.

Rapid chondrolysis of the knee after partial lateral meniscectomy in professional athletes

BACKGROUND

Postoperative knee joint chondrolysis is a rare but serious complication. The aim of our study is to report the clinical presentation, the early, mid and long-term outcomes of rapid chondrolysis after a partial lateral meniscectomy in elite athletes.

METHODS

Clinical records of 10 consecutive cases of rapid chondrolysis after partial lateral meniscectomy in eight professional athletes were retrospectively reviewed. There were seven males and one female with a mean age of 25.2 years (range 20-32 years) at index procedure. An initial conservative approach to its treatment was attempted in all cases. Arthroscopic lavage was advocated in two cases. Patients were clinically reviewed at last follow-up with comparative X-rays, a subjective IKDC, a Lysholm and Tegner scale.

RESULTS

All patients resumed their pre-injury level of activity at a mean 8 (±2.45) months after the index procedure. At a mean of 82 (±36) months of follow-up, the mean subjective IKDC, Lyshom and Tegner scale were respectively 82.64 (±8.61), 86.6 (±6.44), 9 (±1.41). All knees demonstrated joint space narrowing scored Kellgren and Lawrence II (n=1) III (n=4) or IV (n=5) on conventional radiographs.

CONCLUSION

By reviewing the common factors in each of these cases we believe that rapid chondrolysis occurs primarily due to the excessive loading of the articular cartilage in the lateral compartment of the knee. In this series, although the results in the medium term were good, the long-term outcome must be guarded due to the high rate of radiographic osteoarthritis of the lateral compartment seen in this population.

STUDY DESIGN

Retrospective case series, Level IV.

Glenohumeral chondrolysis: part I--clinical presentation and predictors of disease progression

PURPOSE

The objective of this 2-part study is to report on the etiology, clinical findings, and predictors of disease progression (part I) and the results of treatment (part II) in a group of patients with glenohumeral chondrolysis.

METHODS

Forty patients presented with glenohumeral chondrolysis after treatment elsewhere. Twenty patients have been followed up since their initial presentation before arthroplasty (group 1), and 20 patients were referred either for management of complications arising after prosthetic arthroplasty or for evaluation only (group 2).

RESULTS

Thirty-seven patients received an intra-articular pain pump (IAPP) delivering bupivacaine, and 3 patients had prominent suture anchors or tacks. Symptoms related to chondrolysis developed in patients at a mean of 9.8 months (range, 1 to 34 months) after the index procedure. Radiographs showed joint space obliteration in 30 of 40 patients at most recent follow-up or before arthroplasty. Of the patients receiving an IAPP delivering bupivacaine, the majority received 0.5% with epinephrine. Higher bupivacaine dose (P < .05) and female gender (P < .05) were associated with a longer interval to onset of symptoms. In addition, a shorter interval to onset of symptoms predicted the need for subsequent surgery (P < .05) and a shorter interval to second-look arthroscopy (P < .001).

CONCLUSIONS

Post-arthroscopic glenohumeral chondrolysis is a devastating and rapidly evolving condition that most often strikes young patients. The use of IAPPs delivering local anesthetics should be abandoned because nearly all cases of glenohumeral chondrolysis in this series were associated with their use.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Multimodal pain management in orthopedics: implications for joint arthroplasty surgery

Multimodal pain management has become an important part of the perioperative care of patients undergoing total joint replacement. The principle of multimodal therapy is to use interventions that target several different steps of the pain pathway, allowing more effective pain control with fewer side effects. Many different protocols have shown clinical benefit. The goal of this review is to provide a concise overview of the principles and results of multimodal pain management regimens as a practical guide for the management of joint arthroplasty patients.