Transcutaneous Electrical Nerve Stimulation Integrated into Pants for the Relief of Postoperative Pain in Hip Surgery Patients: A Randomized Trial.

Background: The effect of transcutaneous electrical nerve stimulation (TENS) on pain and impression of change was assessed during a 2.5-hour intervention on the first postoperative days following hip surgery in a randomized, single-blinded, placebo-controlled trial involving 30 patients. Methods: Mixed-frequency TENS (2 Hz/80 Hz) was administered using specially designed pants integrating modular textile electrodes to facilitate stimulation both at rest and during activity. The treatment outcome was assessed by self-reported pain Numerical Rating Scale (NRS) and Patient Global Impression of Change (PGIC) scores at four time points. The ability to perform a 3-meter walk test and the use of analgesics were also evaluated. Group comparison and repeated-measure analysis were carried out using nonparametric statistics. Results: The active TENS group exhibited significantly higher PGIC scores after 30 minutes, which persisted throughout the intervention (all p ≤ 0.001). A reduction in NRS appeared after one hour of active TENS, persisting throughout the intervention (all p ≤ 0.05). The median group differences in pain ratings were greater than the minimum clinically important difference, and the analysis of pain trajectories confirmed clinical significance at the individual level. Moreover, patients in the active TENS group were more likely able to perform a 3-meter walk test by the end of the intervention (p = 0.04). Analysis of the opioid-sparing effect of TENS was inconclusive (p = 0.066). No postoperative surgical complications or TENS-related side effects were observed during the study. Conclusion: Mixed-frequency TENS integrated in pants could potentially be an interesting addition to the arsenal of treatments for multimodal analgesia following hip surgery. This trial is registered with NCT05678101.

Motor point heatmap of the calf.

BACKGROUND: Contractions of muscles in the calf induced by neuromuscular electrical stimulation (NMES) may prevent venous thromboembolism, help rehabilitation and optimize strength training, among other uses. However, compliance to NMES-treatment is limited by the use of suboptimal stimulation points which may cause discomfort and less effectivity. Knowledge of where one is most likely to find muscle motor points (MP) could improve NMES comfort and compliance. AIMS: To anatomically map the MPs of the calf as well as to calculate the probability of finding a MP in different areas of the calf. MATERIAL AND METHODS: On 30 healthy participants (mean age 37 years) anatomical landmarks on the lower limbs were defined. The location of the four most responsive MPs on respectively the medial and lateral head of gastrocnemius were determined in relation to these anatomical landmarks using a MP search pen and a pre-set MP search program with 3 Hz continuous stimulation (Search range:4.0-17.5 mA). The anatomy of the calves was normalized and subdivided into a matrix of 48 (6 × 8) smaller areas (3 × 3 cm), from upper medial to lower lateral, in order to calculate the probability of finding a MP in one of these areas. The probability of finding a MP was then calculated for each area and presented with a 95% confidence interval. RESULTS: The MP heatmap displayed a higher concentration of MPs proximally and centrally on the calf. However, there were wide inter-individual differences in the location of the MPs. The highest probability of finding a MP was in area 4, located centrally and medially, and in area 29, located centrolaterally and around the maximum circumference, both with 50% probability (95% CI: 0.31-0.69). The second highest probability of finding MPs was in areas 9, 10, 16, proximally and medially, all with 47% probability (95% CI: 0.28-0.66). These areas 4, 9, 10, 16 and 29 exhibited significantly higher probability of finding motor points than all areas with a mean probability of 27% and lower (p < 0.05) The lateral and distal outskirts exhibited almost zero probability of finding MPs. CONCLUSIONS: This MP heatmap of the calf could be used to expedite electrode placement and to improve compliance in order to receive consistent and enhanced results of NMES treatments.

Effect of Surgeon Experience on Long-Term Patient Outcomes in Surgical Repair of Acute Achilles Tendon Rupture.

BACKGROUND: The effect of surgeon experience on patient outcomes after surgical Achilles tendon rupture (ATR) repair has so far been unknown. PURPOSE: To examine whether patient-reported and functional outcomes as well as adverse events after surgical ATR repair differ between orthopaedic specialist surgeons and resident surgeons. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We retrospectively analyzed data from 295 patients treated with surgical ATR repair with standardized techniques. The level of surgeon experience (specialist vs resident) and number of adverse events (rerupture, infection, and deep venous thrombosis) were recorded. Patient-reported and functional outcomes were assessed 12 months postoperatively using the validated Achilles tendon total rupture score (ATRS) and the heel-rise test, respectively. Analysis of covariance was used to compare differences in outcomes between specialist surgeons and resident surgeons. Pearson chi-square or Fisher exact test was used for analysis of adverse events. RESULTS: The mean ATRS at 12 months for patients operated on by resident surgeons was significantly higher compared with specialist surgeons (85.9 [95% CI, 80.3-91.5] vs 77.8 [95% CI, 73.8-81.9]; P = .028). In addition, the lateral difference (operated vs unoperated side) in mean total concentric work and number of heel-rise repetitions at 12 months was smaller in patients operated on by resident surgeons (P = .011 and 0.015, respectively). The number of adverse events did not differ significantly between the 2 groups. CONCLUSION: Resident surgeons achieved patient-reported and functional outcomes at least as good as those of specialist surgeons in surgical ATR repair, with a similar risk of adverse events.

Textile Electrodes: Influence of Electrode Construction and Pressure on Stimulation Performance in Neuromuscular Electrical Stimulation (NMES).

The major reason for preventable hospital death is venous thromboembolism (VTE). Non-pharmacological treatment options include electrical stimulation or compression therapy to improve blood flow in the extremities. Textile electrodes offer potential to replace bulky devices commonly used in this field, thereby improving the user compliance. In this work, the performance of dry and wet knitted electrodes in combination with pressure application to the electrode was evaluated in neuromuscular electrical stimulation (NMES). A motor point stimulation on the calf was performed on nine healthy subjects to induce a plantarflexion and the required stimulation intensity as well as the perceived pain were assessed. The performance of the different electrode constructions was compared and the influence of the pressure application was analysed. The results show that wet textile electrodes (0.9 % saline solution) perform significantly better than dry electrodes. However, opportunities were found for improving the performance of dry textile electrodes by using an uneven surface topography in combination with an intermediate to high pressure application to the electrode (> 20 mmHg), e.g. by using a compression stocking. Moreover, the smaller of the two tested electrode areas (16 cm2; 32 cm2) appears to be favourable in terms of stimulation comfort and efficiency.

Higher pyruvate levels after Achilles tendon rupture surgery could be used as a prognostic biomarker of an improved patient outcome.

PURPOSE: The primary aim of this study was to assess the relationship between the metabolites lactate and pyruvate in the healing tendon after Achilles tendon rupture (ATR) and patient-reported outcome at 6 and 12 months. A secondary aim was to evaluate which underlying factors regulate lactate and pyruvate concentrations. METHODS: Lactate and pyruvate concentrations were measured two weeks post-operatively in both the healing- and healthy Achilles tendon in 109 patients (90 men, 19 women; mean age 40 ± 7.9 years). Patient demographics, degree of physical activity, timing of surgery, operation time, patient-reported loading and step counts were investigated in relation to metabolite concentrations. At 6 and 12 months, the Achilles tendon Total Rupture Score (ATRS) questionnaire was used to assess patient outcome. RESULTS: The mean number of steps taken during the post-operative days 1-10 was the only factor significantly related to the mean concentration of lactate (R2 = 0.34, p = 0.038), and pyruvate (R2 = 0.46, p = 0.006). Pyruvate was demonstrated as the only factor significantly associated with ATRS at both 6 months (R2 = 0.32, p = 0.003) and at 12 months (R2 = 0.37, p = 0.004) using multiple linear regression. CONCLUSION: The mean concentration of pyruvate during early ATR healing may predict patient outcome at 6 and 12 months post-operatively and possibly be used as a biomarker of healing. Early mobilization with an increased number of steps taken is an important clinical strategy to improve the metabolite concentrations during healing. LEVEL OF EVIDENCE: III.

Reduced Time to Surgery Improves Patient-Reported Outcome After Achilles Tendon Rupture.

BACKGROUND: Patient outcome after an acute Achilles tendon rupture (ATR) continues to be suboptimal and heterogeneous. Thus, prognostic factors are called for to optimize evidence-based ATR treatment protocols; however, the influence of delayed time from injury to surgery (TTS) on patient outcome after ATR remains largely unknown. PURPOSE: To determine whether patient outcomes and adverse events after surgical repair of acute ATR are related to delayed TTS. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Two hundred twenty-eight patients with ATR who were treated with uniform anesthetic and surgical techniques, within 10 days after injury, were retrospectively assessed. TTS depended on availability of the operating theater, and neither surgeon nor patient could influence the TTS. Patients were assigned to 1 of 3 groups: short TTS (<48 hours), intermediate TTS (48-72 hours), and long TTS (>72 hours). Patient-reported outcome at 1 year was assessed with the validated Achilles tendon Total Rupture Score, with scores higher than 80 on a 0- to 100-point scale indicating an overall good outcome. The incidences of adverse events (perioperative and postoperative) and deep venous thrombosis were assessed. RESULTS: Short TTS was significantly associated with increased rate of good outcome and reduced risk of adverse events. Seventy-one percent (95% CI, 60%-83%) of the patients with short TTS attained a good outcome compared with 44% (95% CI, 33%-56%) of the patients with long TTS ( P = .002), with the intermediate TTS group in between, 63% (95% CI, 47%-78%). The incidence of adverse events was significantly reduced among patients with short TTS, 1.4% (95% CI, 1%-4%) compared with those with intermediate TTS, 11% (95% CI, 2%-21%) ( P = .035) and those with long TTS, 14.8% (95% CI, 7%-23%) ( P = .003). The risk of sustaining a deep venous thrombosis was not statistically significantly different among the 3 groups ( P = .15). CONCLUSION: Patients with acute ATR undergoing operation within 48 hours after injury had better outcomes and a lower number of adverse events compared with patients undergoing operation after 72 hours. These results align with evidence-based recommendations from other surgical disciplines and should be used as guidelines for optimizing ATR treatment protocols. Registration: NTC01317160 (ClinicalTrials.gov identifier).