The inhibitory effects of local anaesthetics on the vascular flare responses to bradykinin and substance P in human skin*

Inhibition of angiotensin converting enzyme increases PKCβI isoform expression via activation of substance P and bradykinin receptors in cultured astrocytes of mice

BACKGROUND

Angiotensin-converting enzyme inhibitor (ACEi) inhibits the catalysis of angiotensin I to angiotensin II and the degradation of substance P (SP) and bradykinin (BK). While the possible relationship between ACEi and SP in nociceptive mice was recently suggested, the effect of ACEi on signal transduction in astrocytes remains unclear.

OBJECTIVES

This study examined whether ACE inhibition with captopril or enalapril modulates the levels of SP and BK in primary cultured astrocytes and whether this change modulates PKC isoforms (PKCα, PKCβI, and PKCε) expression in cultured astrocytes.

METHODS

Immunocytochemistry and Western blot analysis were performed to examine the changes in the levels of SP and BK and the expression of the PKC isoforms in primary cultured astrocytes, respectively.

RESULTS

The treatment of captopril or enalapril increased the immunoreactivity of SP and BK significantly in glial fibrillary acidic protein-positive cultured astrocytes. These increases were suppressed by a pretreatment with an angiotensin-converting enzyme. In addition, treatment with captopril increased the expression of the PKCβI isoform in cultured astrocytes, while there were no changes in the expression of the PKCα and PKCε isoforms after the captopril treatment. The captopril-induced increased expression of the PKCβI isoform was inhibited by a pretreatment with the neurokinin-1 receptor antagonist, L-733,060, the BK B1 receptor antagonist, R 715, or the BK B2 receptor antagonist, HOE 140.

CONCLUSIONS

These results suggest that ACE inhibition with captopril or enalapril increases the levels of SP and BK in cultured astrocytes and that the activation of SP and BK receptors mediates the captopril-induced increase in the expression of the PKCβI isoform.

Continuous preperitoneal infusion of ropivacaine for postoperative analgesia in patients undergoing major abdominal or pelvic surgeries. A prospective controlled randomized study

Background and Aims

This study was conducted to compare continuous preperitoneal infusion (CPI) with continuous epidural infusion (CEI) of ropivacaine for pain relief and effect on pulmonary functions after major abdominal and pelvic surgeries.

Material and Methods

One hundred patients were randomized into two equal groups. Patients in CPI group (n = 50) received analgesia by continuous infusion of 0.2% ropivacaine, whereas those in the CEI group (n = 50) received continuous epidural infusion of 0.2% ropivacaine. The primary outcome was the first request of analgesia. The secondary outcome was the influence on the pulmonary functions.

Results

The time for the first request of analgesia was longer in the CPI group compared with that in the CEI group (7.3 ± 1.6 vs. 4.1 ± 1.1 h with P value = 0.001). The daily dose of morphine was lesser in CPI versus CEI group (11.3 ± 1 against 17.4 ± 0.9 mg). The pulmonary function tests were comparable except peak expiratory flow rate, which was better in CPI (170 ± 5.4) than CEI group (148.1 ± 5.8; with P value = 0.001).

Conclusion

Continuous preperitoneal infusion provides a superior analgesic effect than the continuous epidural infusion as regards delayed first request of analgesia, better pain scores, lesser usage of additional analgesics with better respiratory function.

Epicardial Interventions: Impact of Liposomal Bupivacaine on Postprocedural Management (The EPI-LIBRE Study)

Background:

Electrophysiological procedures such as epicardial ventricular tachycardia ablation and Lariat left atrial appendage ligation that involve the epicardial space are typically associated with significant postoperative pain due to mechanical irritation and associated inflammation. There is an unmet need for an effective pain management strategy in this group of patients. We studied how this impacts patient comfort and duration of hospitalization and other associated comorbidities related to pericardial access.

Methods:

This is a multicenter retrospective study including 104 patients who underwent epicardial ventricular tachycardia ablation and Lariat left atrial appendage exclusion. We compared 53 patients who received postprocedural intrapericardial liposomal bupivacaine (LB)+oral colchicine (LB group) and 51 patients who received colchicine alone (non-LB group) between January 2015 and March 2018.

Results:

LB was associated with significant lowering of median pain scale at 6 hours (1.0 [0–2.0] versus 8.0 [6.0–8.0], P <0.001), 12 hours (1.0 [1.0–2.0] versus 6.0 [5.0–6.0], P <0.001), and up to 48 hours postprocedure. Incidence of acute severe pericarditis delayed pericardial effusion and gastrointestinal adverse effects were similar in both groups. Median length of stay was significantly lower in LB group (2.0 versus 3.0; adjusted linear coefficient −1 [CI −1.3 to −0.6], P <0.001). Subgroup analysis demonstrated similar favorable outcomes in both Lariat and epicardial ventricular tachycardia ablation groups.

Conclusions:

Addition of intrapericardial postprocedural LB to oral colchicine in patients undergoing epicardial access during ventricular tachycardia ablation or Lariat procedure is associated with significantly decreased numeric pain score up to 48 hours compared with colchicine alone. It is also associated with significantly shorter length of hospital stay without an increase in the risk of adverse events.

Short-term results of intrathecal injection of low-dose bupivacaine in outpatients with chronic low back and lower extremity pain

PURPOSE

To investigate the safety and efficacy of intrathecal injection as an alternative to epidural injection for analgesia.

METHODS

Seventy consecutive outpatients with chronic low back and lower extremity pain received lumbar intrathecal injection of low-dose isobaric bupivacaine using a 25-gauge pencil-point needle. The patients received 0.5, 1.0, and 1.5 mg of bupivacaine at 1-week intervals to determine the optimal dose. Thereafter, they received two more weekly injections with the optimal dose. The safety and efficacy of the treatment were assessed over a 1-year period.

RESULTS

No serious adverse events were encountered. The optimal dose of bupivacaine (1.0 mg in 60% of patients) alleviated pain and disability (both, p < 0.0001) and provided anesthesia below L1 (L5-T6). Motor block was negligible, and balance impairment improved relative to baseline (p < 0.0001).

CONCLUSION

Intrathecal injection of low-dose bupivacaine offers a safe and effective treatment for chronic low back and lower extremity pain.

TRIAL REGISTRATION

The study was approved by the Kitasato University Hospital Ethics Committee, and written informed consent was obtained from all individual participants included in the study. This trial was registered with the University Hospital Medical Information Network (UMIN000008670). These slides can be retrieved under electronic supplementary material.

Lignocaine Versus Ropivacaine Infiltration for Postpartum Perineal Pain

Background:

Millions of women worldwide undergo postpartum perineal repair under local infiltration. Inadequate postpartum pain management can negatively impact a mother's physical and psychological recovery.

Aims:

To study and compare the analgesic effect and maternal satisfaction with lignocaine versus ropivacaine infiltration for postpartum perineal pain relief.

Materials and Methods:

After clearance from the Institutional Ethics Committee, a double-blind prospective randomized study carried out on 100 parturients of aged 18–40 years who had spontaneous vaginal delivery, comparing 1% lignocaine and 0.75% ropivacaine infiltration for the repair of selective episiotomy or perineal injury. Time of the first analgesic (TFA) demand, maternal satisfaction at 24 h, and visual analog scale (VAS) pain score were studied.

Statistical Analysis:

Chi-square test and Student's t-test were used and P < 0.05 was considered as significant.

Results:

VAS pain score was significantly lower at 2 and 4 h in ropivacaine group versus lignocaine group (P < 0.0001). Significantly, longer TFA (10.2 ± 1.54 vs. 2.20 ± 0.44 h, P < 0.0001) and higher percentage of maternal satisfaction (86% vs. 44%) were observed in ropivacaine as compared to lignocaine group (P < 0.0001).

Conclusions:

Prolonged analgesia and higher rate of maternal satisfaction were found when ropivacaine infiltration was used for perineal repair as compared to lignocaine.

Intraperitoneal ropivacaine and early postoperative pain and postsurgical outcomes after laparoscopic herniorrhaphy in toddlers: a randomized clinical trial

BACKGROUND

Postoperative pain can cause physiological distress, postoperative complications, and extended lengths of hospitalized stay. In children, management of postoperative pain is still recognized as being inadequate.

OBJECTIVE

The aim of this trial was to investigate the effects of intraperitoneal ropivacaine on postoperative pain, and recovery of bowel function and emetic events after laparoscopic herniorrhaphy in toddlers.

METHODS

Seventy-six children aged from 9 months to 3 years were recruited between August 2013 and June 2014 at Tongji Hospital and randomly assigned into two groups. One group received intraperitoneal ropivacaine right before surgery and the control group received intraperitoneal saline. A standard combined general anesthesia procedure was performed under regular monitoring. Postoperative pain was assessed by the FLACC scale. Postoperative analgesic consumption, time to flatus, time to first stool, and postoperative emetic events were also recorded.

RESULTS

When compared with the control group, children who received intraperitoneal ropivacaine experienced less pain 0-4 h after surgery [P < 0.001, difference in median FLACC (95% CI) for 2 h time point is 2.00 (0.87-3.13), for 4 h time point is 1.00 (0.55-1.45)]. In addition, the number of toddlers who received analgesia 0-24 h after surgery in the ropivacaine group was lower than that in the control group [P < 0.001, difference in proportions (95% CI) is 0.575 (0.3865-0.7638)]. Compared with the control group, time to flatus in ropivacaine group was also much shorter [21.1 h vs 16.7 h, P = 0.04, difference in mean (95% CI) is 4.4 (1.49-7.28)], and the time to first stool after surgery was earlier in the ropivacaine group [30.7 h vs 25.6 h, P = 0.003, difference in mean (95% CI) is 5.1 (1.78-8.45)]. Furthermore, the incidence of emetic events in the ropivacaine group was significantly lower than the control group [32.4% vs 11.1%, P = 0.03, difference in proportions (95% CI) is 0.212 (0.0246-0.4002)].

CONCLUSION

The present results indicate that intraperitoneal ropivacaine reduces early postoperative pain and improves recovery after laparoscopic herniorrhaphy in toddlers. Therefore, IPLA is a good stratagem for postoperative pain management after laparoscopic surgery in toddlers.

Intra-articular (IA) ropivacaine microparticle suspensions reduce pain, inflammation, cytokine, and substance p levels significantly more than oral or IA celecoxib in a rat model of arthritis

Current therapeutic treatment options for osteoarthritis entail significant safety concerns. A novel ropivacaine crystalline microsuspension for bolus intra-articular (IA) delivery was thus developed and studied in a peptidoglycan polysaccharide (PGPS)-induced ankle swelling rat model. Compared with celecoxib controls, both oral and IA, ropivacaine IA treatment resulted in a significant reduction of pain upon successive PGPS reactivation, as demonstrated in two different pain models, gait analysis and incapacitance testing. The reduction in pain was attended by a significant reduction in histological inflammation, which in turn was accompanied by significant reductions in the cytokines IL-18 and IL-1β. This may have been due to inhibition of substance P, which was also significantly reduced. Pharmacokinetic analysis indicated that the analgesic effects outlasted measurable ropivacaine levels in either blood or tissue. The results are discussed in the context of pharmacologic mechanisms both of local anesthetics as well as inflammatory arthritis.

P2X7 is involved in the anti-inflammation effects of levobupivacaine

BACKGROUND

We sough to elucidate whether purinergic P2X7 receptor is actively involved in the effects of levobupivacaine on inhibiting microglia activation.

MATERIALS AND METHODS

Microglia were treated with lipopolysaccharide (LPS, 50 ng/mL), LPS plus levobupivacaine (50 μM), or LPS plus levobupivacaine plus the P2X7 receptor agonist Bz-ATP (100 μM) and denoted as the LPS, LPS + Levo, and LPS + Levo + Bz-ATP group, respectively. Microglia activation was measured by assaying inflammatory molecules expression. Microglia activation was also measured by assaying neuronal cell viability using coculture of microglia and neurons, as activated microglia may cause neuron injury. We also measured the levels of P2X7 receptor activation in microglia using ethidium uptake assay.

RESULTS

Our data confirmed the effects of levobupivacaine on inhibiting inflammatory molecules upregulation in activated microglia, as the concentrations of interleukin (IL)-1β, tumor necrosis factor α, IL-6, and macrophage inflammatory protein 2, of the LPS + Levo group were significantly lower than those of the LPS group (all P < 0.05). Moreover, Bz-ATP significantly abrogated the inhibitory effects of levobupivacaine, as concentrations of IL-1β, tumor necrosis factor α, IL-6, and macrophage inflammatory protein 2 of the LPS + Levo + Bz-ATP group were significantly higher than those of the LPS + Levo group (all P < 0.05). In contrast, neuronal cell viability of the LPS + Levo group was significantly higher than those of the LPS and LPS + Levo + Bz-ATP groups (P = 0.012 and 0.002). Moreover, levels of P2X7 receptor activation of the LPS and LPS + Levo + Bz-ATP groups were significantly higher than that of the LPS + Levo group (P = 0.003 and 0.006).

CONCLUSIONS

P2X7 receptor is involved in the effects of levobupivacaine on inhibiting microglial activation.

Comparison of the potency of different propofol formulations: a randomized, double-blind trial using closed-loop administration

BACKGROUND

Several commercial formulations of propofol are available. The primary outcome of this study was the required dose of propofol alone or combined with lidocaine to achieve induction of general anesthesia.

METHODS

This multicenter, double-blinded trial randomized patients (American Society of Anesthesiologists physical status I-III) just before elective surgery with the use of a computer-generated list. Three different propofol 1% formulations-Diprivan (Astra-Zeneca, Cheshire, United Kingdom), Propoven (Fresenius-Kabi AG, Bad Homburg, Germany), and Lipuro (B-Braun, Melshungen AG, Germany)-were compared with either placebo (saline solution) or lidocaine 1% mixed to the propofol solution. Depth of anesthesia was automatically guided by bispectral index and by a computerized closed-loop system for induction, thus avoiding dosing bias. The authors recorded the total dose of propofol and duration of induction and the patient's discomfort through a behavioral scale (facial expression, verbal response, and arm withdrawal) ranging from 0 to 6. The authors further evaluated postoperative recall of pain using a Visual Analog Scale.

RESULTS

Of the 227 patients enrolled, 217 were available for analysis. Demographic characteristics were similar in each group. Propoven required a higher dose for induction (2.2 ± 0.1 mg/kg) than Diprivan (1.8 ± 0.1 mg/kg) or Lipuro (1.7 ± 0.1 mg/kg; P = 0.02). However, induction doses were similar when propofol formulations were mixed with lidocaine. Patient discomfort during injection was significantly reduced with lidocaine for every formulation: Diprivan (0.5 ± 0.3 vs. 2.3 ± 0.3), Propoven (0.4 ± 0.3 vs. 2.4 ± 0.3), and Lipuro (1.1 ± 0.3 vs. 1.4 ± 0.3), all differences significant, with P < 0.0001. No adverse effect was reported.

CONCLUSION

Plain propofol formulations are not equipotent, but comparable doses were required when lidocaine was concomitantly administered.

Systemic ropivacaine diminishes pain sensitization processes: a randomized, double-blinded, placebo-controlled, crossover study in healthy volunteers

Introduction

Ropivacaine is a local anesthetic widely used for regional anesthesia. One of its advantages is low toxicity at plasma concentrations reached systemically during continuous peripheral or central nervous block. The objective of this study was to test the effect of systemic ropivacaine on pain, hyperalgesia, dynamic allodynia, and flare response.

Methods

This randomized, double-blinded, placebo-controlled, crossover study was carried out in at the Clinical Trials Centre, University of Zurich, Switzerland. Twenty healthy male volunteers were included in the study. Exclusion criteria were contraindications or hypersensitivity to local anesthetics, vulnerable subjects (intellectually or mental impaired), drug, alcohol or nicotine abuse, known peripheral neuropathies, diabetes mellitus and/or congestive heart disease. Ropivacaine and saline were infused intravenously during a subcutaneous electrical stimulation. The stimulation software adjusted the stimulus strength according to the rating on a numeric rating scale (NRS; 0–10) maintaining a NRS of 5. Areas of punctate hyperalgesia, dynamic allodynia, and flare response were measured before and after the infusion.

Results

The area of hyperalgesia increased significantly with saline (303 ± 380%, P < 0.05) and ropivacaine (186 ± 137%, P < 0.05). The area of allodynia (253 ± 299%, P < 0.05) and flare response (112 ± 24%, P < 0.05) increased only during the placebo infusion.

Conclusion

The results of this study imply that systemic ropivacaine may diminish pain sensitization processes.

Electronic supplementary material

The online version of this article (doi:10.1007/s40122-013-0021-z) contains supplementary material, which is available to authorized users.

Investigation of effects of levobupivacaine injection to rabbit knee joint on histopathologic changes of joint cartilage tissue and changes of serum biochemical parameters

The aim of this study is to evaluate the effects of intra-articular levobupivacaine on rabbit knee articular cartilage and certain biochemical parameters in the blood. A total of 24 New Zealand rabbits were included to study. Blood sampling was carried out in all animals on the first day, then the subjects were randomly allocated either to the control group (Group C, n = 9) or to the levobupivacaine group (Group L, n = 15). Group C underwent each two intra-articular injections of saline, 0.25 mL into the right knee and 0.50 mL into the left one. Group L was injected 0.25 mL (1.25 mg) of levobupivacaine into the right knee and 0.50 mL (2.5 mg) into the left one. The groups were divided randomly into three. Tissue and blood samples for histologic and biochemical examination were collected from Groups C1 and L1 on the first, C2 and L2 on the second, and C3 and L3 on the tenth day of the study. Interleukin-1β (IL-1 β), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) levels were analyzed. No statistically significant differences could be detected when comparing either left or right joints within the same groups and with Group C and L (P > 0.05). Significant elevations of biochemical parameters were found in Group C. It is concluded that levobupivacaine does not lead to significant histologic changes in rabbit articular cartilage. Significant elevations of biochemical parameters being generally found in the C Group, it is thought that such elevations are not linked to levobupivacaine. Intra-articular levobupivacaine may be a safe alternative for use in post-operative analgesia.

Duration of action of a topical anaesthetic formulation for pain management of mulesing in sheep

OBJECTIVE

To investigate the effect of topical anaesthesia on 'mothering up' of lambs after mulesing and marking, and for pain alleviation over a 24-h period.

DESIGN

Two separate trials were performed on Merino lambs undergoing the mules procedure for flystrike prevention, to assess the efficacy of immediate postoperative topical anaesthetic wound dressing containing lignocaine (hydrochloride) 40.6 g/L, bupivacaine (hydrochloride) 4.5 g/L, adrenaline (tartrate) 24.8 mg/L and cetrimide 5.0 g/L in a gel base (Bayer Animal Health, Gordon, NSW, Australia).

METHODS

In both trials, lambs were assigned to one of three treatment regimens: control, mules procedure with topical anaesthetic (0.5 mL/kg) and mules procedure without topical anaesthetic treatment. Parameters measured included body weight, assessment of skin and wound sensitivity to light touch and pain stimulation, behavioural responses and time to mother up and to feed.

RESULTS

In both trials there was rapid (1 min) and prolonged (up to 24 h) wound analgesia as shown by lower scores for light touch (P<0.001) and pain responses (P<0.001), with absent or significantly diminished primary and secondary hyperalgesia (P≤0.05) and significant reduction in pain-related behaviours (P<0.001) in treated versus untreated lambs.

CONCLUSION

Significant pain alleviation and improved recovery can be achieved in lambs for at least 24 h after mulesing through the use of topical anaesthesia. It is suggested that the haemostatic action of adrenalin, together with inhibition of the inflammatory cascade and the barrier effect of the gel within the product, may explain the prolonged anaesthesia up to 24 h observed in the present study. These results suggest that topical anaesthesia has the capacity to dramatically improve the welfare of lambs undergoing mulesing.

Maxadilan, the Lutzomyia longipalpis vasodilator, drives plasma leakage via PAC1-CXCR1/2-pathway

Experiments were designed to determine if the vasodilatory peptides maxadilan and pituitary adenylate cyclase-activating peptide (PACAP-38) may cause plasma leakage through activation of leukocytes and to what extent these effects could be due to PAC1 and CXCR1/2 receptor stimulation. Intravital microscopy of hamster cheek pouches utilizing FITC-dextran and rhodamine, respectively, as plasma and leukocyte markers was used to measure arteriolar diameter, plasma leakage and leukocyte accumulation in a selected area (5mm(2)) representative of the hamster cheek pouch microcirculation. Our studies showed that the sand fly vasodilator maxadilan and PACAP-38 induced arteriolar dilation, leukocyte accumulation and plasma leakage in postcapillary venules. The recombinant mutant of maxadilan M65 and an antagonist of CXCR1/2 receptors, reparixin, and an inhibitor of CD11b/CD18 up-regulation, ropivacaine, inhibited all these effects as induced by maxadilan. Dextran sulfate, a complement inhibitor with heparin-like anti-inflammatory effects, inhibited plasma leakage and leukocyte accumulation but not arteriolar dilation as induced by maxadilan and PACAP-38. In vitro studies with isolated human neutrophils showed that maxadilan is a potent stimulator of neutrophil migration comparable with fMLP and leukotriene B(4) and that M65 and reparixin inhibited such migration. The data suggest that leukocyte accumulation and plasma leakage induced by maxadilan involves a mechanism related to PAC1- and CXCR1/2-receptors on leukocytes and endothelial cells.

Continuous subcutaneous instillation of bupivacaine compared to saline reduces interleukin 10 and increases substance P in surgical wounds after cesarean delivery

BACKGROUND

Recent evidence suggests that locally delivered local anesthetics may exert tissue-damaging effects such as chondrolysis after intraarticular injection. Alteration of the inflammatory response is a potential mechanism for local anesthetic-induced tissue toxicity. In this study, we tested the effects of continuous local anesthetic infiltration on the release of inflammatory and nociceptive mediators in skin wounds after cesarean delivery.

METHODS

Thirty-eight healthy women undergoing cesarean delivery with spinal anesthesia were enrolled in this study, and were randomized to receive subcutaneous surgical wound infiltration with bupivacaine 5 mg/mL or saline at 2 mL/h for 24 hours after cesarean delivery. Wound exudate was sampled at 1, 3, 5, 7, and 24 hours after cesarean delivery using a subcutaneous wound drain technique. Cytokines, chemokines, substance P, prostaglandin E(2), and nerve growth factor were assayed using multiplex Bio-Plex® (Bio-Rad, Hercules, CA) and enzyme-linked immunosorbent assays.

RESULTS

Bupivacaine wound infusion resulted in a significant decrease of interleukin 10 and increase of substance P in wounds compared with saline infusion (area under the 24-hour concentration-time curve; P < 0.001). No statistically significant differences were detected for other cytokines, nerve growth factor, and prostaglandin E(2).

CONCLUSIONS

This study demonstrates that the continuous administration of clinically used doses of bupivacaine into wounds affects the local composition of wound mediators. Observed changes in interleukin 10 are compatible with a disruption of antiinflammatory mechanisms. Whether such modulation combined with the release of the proinflammatory mediator substance P results in an overall proinflammatory wound response will require future studies of wound healing.

Lidocaine eye drops attenuate pain associated with ophthalmic postherpetic neuralgia

BACKGROUND

Topical lidocaine (LDC) treatment using a gel or patch preparation is effective in the treatment of postherpetic neuralgia (PHN), but neither is suited for the eye in patients with ophthalmic PHN. Herein, we examined the effect of LDC 4% eye drops on ophthalmic PHN pain.

METHODS

Twenty-four patients with ophthalmic PHN were randomized to receive 0.4 mL eye drops of either LDC 4% or saline placebo (PBO) in the painful eye. After a 7-day period, the patients were crossed over to receive the alternative eye drops. The pain in the eye and the forehead was assessed with a visual analog scale (VAS) before and 15 minutes after treatment. Patients used a descriptive scale to grade pain outcome and were asked to note whether the pain returned and how long after therapy it recurred.

RESULTS

LDC significantly decreased the VAS score of persistent pain in the eye (baseline: 5.9 +/- 2.2 cm; 15 minutes after eye drops: 0.9 +/- 1.8 cm, mean +/- SD [P < 0.01]) and in the forehead (baseline: 6.3 +/- 2.0 cm; 15 minutes after eye drops: 2.6 +/- 2.7 cm [P < 0.01]). The delta change in these VAS scores between LDC and PBO was significant (P < 0.01). Moreover, pain was described as moderate or better by 23 patients after they received LDC and 4 patients of the PBO group. The effect of LDC persisted for a median of 36 hours (range, 8-96 hours) after application.

CONCLUSIONS

This study suggests that LDC provides a significant improvement of ophthalmic PHN because of its prompt analgesia, lack of systemic side effects, and convenience of use.

Low-energy extracorporeal shock wave therapy as a treatment for medial tibial stress syndrome

BACKGROUND

Medial tibial stress syndrome (MTSS) is a pain syndrome along the tibial origin of the tibialis posterior or soleus muscle. Extracorporeal shock wave therapy (SWT) is effective in numerous types of insertional pain syndromes.

HYPOTHESIS

Shock wave therapy is an effective treatment for chronic MTSS.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Forty-seven consecutive subjects with chronic recalcitrant MTSS underwent a standardized home training program, and received repetitive low-energy radial SWT (2000 shocks; 2.5 bars of pressure, which is equal to 0.1 mJ/mm(2); total energy flux density, 200 mJ/mm(2); no local anesthesia) (treatment group). Forty-seven subjects with chronic recalcitrant MTSS were not treated with SWT, but underwent a standardized home training program only (control group). Evaluation was by change in numeric rating scale. Degree of recovery was measured on a 6-point Likert scale (subjects with a rating of completely recovered or much improved were rated as treatment success).

RESULTS

One month, 4 months, and 15 months from baseline, success rates for the control and treatment groups according to the Likert scale were 13% and 30% (P < .001), 30% and 64% (P < .001), and 37% and 76% (P < .001), respectively. One month, 4 months, and 15 months from baseline, the mean numeric rating scale for the control and treatment groups were 7.3 and 5.8 (P < .001), 6.9 and 3.8 (P < .001), and 5.3 and 2.7 (P < .001), respectively. At 15 months from baseline, 40 of the 47 subjects in the treatment group had been able to return to their preferred sport at their preinjury level, as had 22 of the 47 control subjects.

CONCLUSION

Radial SWT as applied was an effective treatment for MTSS.