Pain levels and patient comfort after lower limb arthroplasty comparing i.v. patient-controlled analgesia, continuous peripheral nerve block and neuraxial analgesia: a retrospective cohort analysis of clinical routine data.

BACKGROUND: Insufficient pain control after lower limb arthroplasty results in delayed recovery and increased risk for pain chronicization. The ideal kind of analgesia is still discussed controversially. We conducted a retrospective analysis of single-center routine data from a German university hospital, including patients receiving either total hip (THA) or knee arthroplasty (TKA). METHODS: All patients received general anesthesia. Patients undergoing THA received either continuous epidural ropivacaine infusion (0.133%, Epi) or patient-controlled analgesia (PCA) with the Wurzburg Pain Drip (tramadol, metamizole and droperidol, WPD) or with piritramide (Pir). After TKA, patients received either continuous femoral nerve block (ropivacaine 0.2%, PNB) or Pir. RESULTS: The analyzed cohort comprised 769 cases. Use of WPD after THA (n = 333) resulted in significantly reduced Numeric Rating Scale (NRS) values at rest, compared to Epi (n = 48) and Pir (n = 72) (.75 [IQR 1.14] vs. 1.17 [1.5], p = .02 vs. 1.47 [1.33], p < .0001) as well as maximum NRS scores (2.4 [1.7] vs. 3.29 [1.94], p < .001 vs. 3.32 [1.76], p < .0001). Positive feedback during follow-up visits was significantly increased in patients with a WPD PCA (p < .0001), while negative feedback (senso-motoric weakness/technical problems/nausea/dizziness/constipation) was particularly increased in Epi patients and lowest in those with WPD (p < .0001). After TKA, Pir (n = 131) resulted in significantly reduced NRS values at rest, compared to PNB (n = 185) (1.4 [1.4] vs. 1.6 [1.68], p = .02). Positive feedback was increased in patients with a Pir PCA in comparison with PNB (p = .04), while negative feedback was increased in PNB patients (p = .04). Overall, WPD presented with the lowest rate of any complications (8.7%), followed by Pir (20.2%), PNB (27.6%) and Epi (31.3%) (p < .001). CONCLUSIONS: In the assessed population, the use of a WPD PCA after THA offered better pain control and patient comfort in comparison with continuous epidural or piritramide-based analgesia. After TKA, the use of a Pir PCA provided superior analgesia and a lower complication rate compared to continuous PNB.

Burst Spinal Cord Stimulation Increases Peripheral Antineuroinflammatory Interleukin 10 Levels in Failed Back Surgery Syndrome Patients With Predominant Back Pain.

OBJECTIVES: Burst spinal cord stimulation (SCS) has been reported to reduce back pain and improve functional capacity in Failed Back Surgery Syndrome (FBSS). However, its mechanism of action is not completely understood. Systemic circulating cytokines have been associated with the development of chronic back pain. METHODS: This prospective, feasibility study enrolled 12 refractory FBSS patients with predominant back pain (70% of overall pain) suitable for Burst SCS. Back and leg pain intensity (back pain [VASB ]/leg pain [VASL ]), functional capacity (sleep quality [PSQI]), depressive symptoms (BDI), body weight, stimulation parameters, and plasma levels of pro-inflammatory (Il-1b; TNF; HMGB1)/anti-inflammatory (Il-10) cytokines were collected at baseline and after three months of Burst SCS and compared to healthy controls. RESULTS: Pain intensity (pre VASB : 8.25 ± 0.75 vs. post 1.42 ± 1.24) and functional capacity (PSQI: pre 7.92 ± 3.92 vs. post 3.42 ± 1.24; BDI: pre 20.83 ± 3.56 vs. post 10.92 ± 0.75) significantly improved compared to baseline. Pro-inflammatory HMGB1 remained unchanged (preburst: 3.35 ± 3.25 vs. postburst: 3.78 ± 3.83 ng/mL; p = 0.27; W = -30) versus the HC group (2.53 ± 2.6 ng/mL; p = 0.47; U = 59), while anti-inflammatory IL-10 levels were significantly elevated after burst SCS as compared to baseline (preburst 12.54 ± 22.95 vs. postburst 43.16 ± 74.71 pg/mL; p = 0.03; W = -48) and HC group (HC: 7.03 ± 11.6 vs. postburst 43.16 ± 74.71 pg/mL; p = 0.03; W = -48; p = 0.04). Baseline preburst IL-10 values and preburst VASB significantly correlated (Spearman correlation r = -0.66; p = 0.05; 95 CI -0.86 to -0.24), while correlation was not significant between postburst IL-10 values and postburst VASB (Spearman correlation r = -0.49; p = 0.18; 95 CI -0.83 to -0.15). Postburst IL-10 values correlated significantly with postburst PSQI scores (Spearman correlation r = -0.66; p = 0.05; 95 CI -0.86 to -0.24), while no correlation was found between preburst and postburst changes related to the BDI. CONCLUSIONS: Burst SCS increased systemic circulating anti-inflammatory IL-10, improved FBSS back pain and back pain associated co-morbidities like disrupted sleep architecture and depressive symptoms in FBSS patients. Thus, suggesting a possible relationship between burst SCS and burst-evoked modulation of peripheral anti-inflammatory cytokine IL-10 in chronic back pain.

High Frequency (10 kHz) or Burst Spinal Cord Stimulation in Failed Back Surgery Syndrome Patients With Predominant Back Pain: Preliminary Data From a Prospective Observational Study.

BACKGROUND: Conventional spinal cord stimulation (SCS) exhibits pain relief and improved quality of life in refractory failed back surgery syndrome. However, patients suffering from predominant back pain failed to achieve a favorable neuromodulation outcome. Currently, two new stimulation concepts, the burst and the HF10 stimulation paradigms successfully suppress intractable back pain levels in this difficult-to-treat subgroup. To date, literature data comparing both stimulation patterns is lacking. METHODS: A prospective, observational study was conducted including 16 refractory Failed-back surgery syndrome (FBSS) patients with previous spine surgery and predominant back pain (70% of overall pain) with or without leg pain eligible for burst or high-frequency SCS. At baseline and at a three-month follow-up the pain intensity (back pain (VASB )/leg pain (VASL ), sleep quality (Pittsburgh Sleep Quality Index [PSQI]), changes in severity of depressive symptoms (Beck Depression Inventory [BDI]) and any adverse event related to the implantation and the stimulation were recorded. RESULTS: Overall baseline VASB was significantly suppressed in 14 FBSS patients (eight burst/six patients with 10 HF10) from baseline 7.9 ± 0.7 to 2.3 ± 1 (p < 0.001), while the overall VASL declined significantly from 3.1 ± 1.5 to 1.9 ± 0.83 (p < 0.01). The burst patients experienced significant VASL reduction (burst 1.8 ± 0.7 (p < 0.009) compared to HF10 patients 2.2 ± 1). Two patients failed 10 HF10-trial. The BDI [23.3 ± 2.1 to 13.5 ± 4.5 (p < 0.001)] and the PSQI [7.6 ± 3.7 to 4.2 ± 1.4 (p < 0.003)] dropped down significantly for both modalities. No implantation/stimulation-related complications were observed. CONCLUSIONS: Burst and HF10 SCS performed efficiently and safely in intractable FBSS patients with predominant back pain and deserve more refined, specific investigations to determine their efficacy.