Prevalence of Neuropathic Pain Symptoms in Foot and Ankle Patients

Integrating mechanistic-based and classification-based concepts into perioperative pain management: an educational guide for acute pain physicians

Chronic pain begins with acute pain. Physicians tend to classify pain by duration (acute vs chronic) and mechanism (nociceptive, neuropathic and nociplastic). Although this taxonomy may facilitate diagnosis and documentation, such categories are to some degree arbitrary constructs, with significant overlap in terms of mechanisms and treatments. In clinical practice, there are myriad different definitions for chronic pain and a substantial portion of chronic pain involves mixed phenotypes. Classification of pain based on acuity and mechanisms informs management at all levels and constitutes a critical part of guidelines and treatment for chronic pain care. Yet specialty care is often siloed, with advances in understanding lagging years behind in some areas in which these developments should be at the forefront of clinical practice. For example, in perioperative pain management, enhanced recovery protocols are not standardized and tend to drive treatment without consideration of mechanisms, which in many cases may be incongruent with personalized medicine and mechanism-based treatment. In this educational document, we discuss mechanisms and classification of pain as it pertains to commonly performed surgical procedures. Our goal is to provide a clinical reference for the acute pain physician to facilitate pain management decision-making (both diagnosis and therapy) in the perioperative period.

Prevalence and predisposing factors of neuropathic pain in patients with rotator cuff tears

BACKGROUND

The management of pain in patients with rotator cuff tears can be challenging. Neuropathic pain is reportedly associated with pain occurrence in musculoskeletal diseases. However, to date, few studies have reported on the prevalence of neuropathic pain in patients with rotator cuff tears or identified the factors associated with neuropathic pain in a multicenter study.

METHODS

A total of 391 patients (205 males and 186 females; median age, 67.7 years; range, 27-92 years) with rotator cuff tears were included in this study. The prevalence of neuropathic pain in rotator cuff tears was investigated using the Japanese version of the painDETECT questionnaire for all patients. In addition, factors significantly associated with the occurrence of neuropathic pain were examined using multivariate logistic regression analysis.

RESULTS

Twenty-eight patients (7.2%) were classified into the neuropathic pain group (score ≥19), 97 (24.8%) into the uncertainty regarding neuropathy group (score 13-18), and 266 (68.0%) into the nociceptive pain group (score ≤12). According to the multivariate logistic regression analysis, the independent predictors of neuropathic pain were the VAS score (most severe pain during the past 4 weeks; odds ratio, 1.55; 95% confidence interval [CI], 1.23-2.09) and UCLA shoulder score (odds ratio, 0.81; 95% CI, 0.65-0.97).

CONCLUSIONS

Based on the study findings, the prevalence of neuropathic pain in patients with rotator cuff tear was 7.2%. It is important to investigate the presence or absence of neuropathic pain when treating patients with painful rotator cuff tears, because neuropathy associated with rotator cuff tears may adversely affect patient outcomes.

Utilization of PROMIS Neuropathic Pain Quality for Detection and Monitoring Neuropathic Pain in Heel Pain Patients

Background

Diagnosis and management of neuropathic pain (NP) in foot and ankle patients remain challenging. We investigated the plausibility of using Patient-Reported Outcomes Measurement Information System (PROMIS) Neuropathic Pain Quality (PQ-Neuro) as an initial screening tool to detect NP and track the treatment effects.

Methods

Patients with heel pain were prospectively recruited and grouped to no-NP, mild-NP, and severe-NP based on the initial PROMIS PQ-Neuro t scores. Pain Interference (PI), Physical Function (PF), and Self-Efficacy (SE) scores were evaluated at baseline, 30-day, and 90-day follow-up. Other factors such as age, smoking, body mass index (BMI), low back/neck pain, anxiety/depression, and medications were analyzed. Linear mixed modeling was used to assess the main effects of time and NP on PROMIS t scores, comparing minimal clinically important difference (MCID).

Results

Forty-eight patients with mean age of 52.4 years were recruited. Using the PROMIS PQ-Neuro as the assessment tool, 33 patients (69%) were detected to have NP at baseline-23 (48%) mild and 10 (21%) severe. BMI was the only independent factor associated with NP (P = .011). Higher baseline PQ-Neuro t score was significantly associated with higher follow-up PQ-Neuro (P < .001), PI (P = .005), and lower SE (P = .04) across time points. Patients with NP showed lower PF at baseline with significantly less improvement in PF (3 vs 9.9, P = .035) and did not meet MCID.

Conclusion

Baseline PROMIS PQ-Neuro ≥46 was significantly associated with worse PI and SE across all time points, with less clinically significant improvements in PF. Prevalence of NP in heel pain patients was high. The PROMIS PQ-Neuro may serve as a valuable tool for detection of NP and guiding clinical treatment decision pathways for heel pain patients.

Level of Evidence

Level III, prospective cohort study.

Factors Associated With Poor Patient-Reported Outcomes in Isolated Gastrocnemius Recession for Heel Pain

Background

Gastrocnemius recession is commonly performed for a variety of pathologies of the foot and ankle, yet studies characterizing risk factors associated with patient-reported outcomes are limited. In this cohort study, patient outcomes were compared against the general population for PROMIS scores with correlation analysis comparing demographics and comorbidities. Our primary goal in this study is to identify risk factors associated with poor patient-reported outcomes following isolated gastrocnemius recession for patients with plantar fasciitis or insertional Achilles tendinopathy.

Methods

A total of 189 patients met inclusion criteria. The open Strayer method was preferred. However, if the myotendinous junction could not be adequately visualized without expanding the excision, then a Baumann procedure was performed. The decision between the two did not depend on preoperative contracture. Patient demographics and visual analog scale (VAS) scores were obtained via the electronic medical record. Telephone interviews were completed to collect postoperative Patient-Reported Outcomes Measurement Information System (PROMIS) and Foot Function Index (FFI) scores. The data were analyzed using the type 3 SS analysis of variance test to identify individual patient factors associated with reduced PROMIS, FFI, and VAS scores.

Results

No demographic variables were found to be significantly associated with postoperative complications. Patients who reported tobacco use at the time of surgery had significantly decreased postoperative PROMIS physical function (P = .01), PROMIS pain interference (P < .05), total FFI scores (P < .0001), and each individual FFI component score. Patients undergoing their first foot and ankle surgeries reported numerous significant postoperative outcomes, including decreased PROMIS pain interference (P = .03), higher PROMIS depression (P = .04), and lower FFI pain scores (P = .04). Hypertension was significantly associated with an increased FFI disability score (P = .03) and, along with body mass index (BMI) >30 (P < .05) and peripheral neuropathy (P = .03), significantly higher FFI activity limitation scores (P = .01). Pre- and postoperative VAS scores demonstrated improvement in patient-reported pain from a mean of 5.53 to 2.11, respectively (P < .001).

Conclusion

We found in this cohort that numerous patient factors were independently associated with differences in patient-reported outcomes following a Strayer gastrocnemius recession performed for plantar fasciitis or insertional Achilles tendinopathy. These factors include, but are not limited to, tobacco use, prior foot and ankle surgeries, and BMI. This study strengthens previous reports demonstrating the efficacy of isolated gastrocnemius recession and elucidates variables that may affect patient-reported outcomes.

Level of Evidence

Level III, retrospective cohort study.

Management of chronic non-cancer pain: a framework

Aim: Since publication of the CDC 2016 Guideline, opioid-related mortality in the USA has doubled and a crisis has developed among the 15-20 million Americans with chronic, moderate-to-severe, noncancer pain. Our aim was to develop a comprehensive alternative approach to management of chronic pain. Methods: Analytic review of the clinical literature. Results: Published science provides a solid framework for the management of chronic non-cancer pain, detailed here, even as it leaves many knowledge gaps, which we fill with insights from clinical experience. Conclusion: There is a sufficient basis in science and in clinical experience to achieve adequate control of chronic pain in nearly all patients in a way that adequately balances benefits and potential harms.

A Retrospective Study of the Risk Factors for Postoperative Foot or Ankle Pain in 90 Patients with Varus Osteoarthritis of the Knee who Underwent Total Knee Arthroplasty

Background

The reasons for foot and ankle pain following total knee arthroplasty (TKA) for knee varus osteoarthritis are unknown. This retrospective study aimed to investigate the risk factors for postoperative foot and ankle pain in patients with varus osteoarthritis of the knee who underwent TKA.

Material/Methods

We enrolled 90 patients who underwent TKA for varus knee osteoarthritis. The visual analog scale (VAS) was used to evaluate patients’ foot or ankle pain before and after surgery. The correlation between independent variables (eg, age, sex, body mass index [BMI], ankle osteoarthritis, and varus angle) and foot and ankle pain in patients with osteoarthritis of the knee was measured. Moreover, radiological changes were compared between the groups with and without worsened pain.

Results

No significant difference in VAS was found between patients <60 and ≥60 years of age (P>0.05). Male sex and BMI <30 kg/m² were weakly correlated with preoperative foot or ankle pain. However, patients with varus of ≥6° and preexisting ankle osteoarthritis had a higher incidence of foot or ankle pain before surgery. Moreover, no significant differences in radiological changes were found between the groups with and without worsened foot or ankle pain after surgery (P>0.05).

Conclusions

In male patients with osteoarthritis of the knee, a BMI <30 kg/m², varus of <6°, and no preexisting ankle osteoarthritis were protective factors for foot and ankle pain. TKA corrected knee and ankle malalignment. Therefore, postoperative foot and ankle pain was not associated only with TKA surgery.

Relationship Between Sensory Symptoms, Mulder's Sign, and Dynamic Ultrasonographic Findings in Morton's Neuroma

BACKGROUND

Morton's neuroma (MN) is often a diagnostic dilemma lacking a gold standard set of diagnostic criteria. Advanced imaging of MN is evolving including ultrasonography. The current study aimed to analyze the relationship between ultrasonographic findings and symptoms, clinical data, and operative findings in a subgroup of patients.

METHODS

We evaluated physical examination, ultrasonographic findings, symptoms, and in a subgroup, the operative findings for Morton's neuroma. We analyzed the symptoms, the findings on physical examination, and ultrasonography data and performed a statistical correlation between them. A total of 175 patients were seen for suspected Morton's neuroma during the last 7 years.

RESULTS

Neuropathic pain of the toes was reported in 63% of patients. Presence of ultrasonographic findings suggesting Morton's neuroma was observed in 77% of cases. A mild significant relationship between neuropathic pain and positive ultrasonographic findings was observed. We found a strong correlation between ultrasonographic and clinical evaluation, but more than half with clinical negative Morton's neuroma had positive findings at ultrasonography. In the subgroup of operatively treated patients (n = 44) surgery confirmed Morton's neuroma in all patients who had positive ultrasonography findings.

CONCLUSIONS

The current study suggests that the association of ultrasonographic evaluation and clinical evaluation can be very useful for the management of Morton's neuroma. Our study could help with the development of a multiperspective approach in the diagnosis of Morton's neuroma.

LEVEL OF EVIDENCE

Level II, prospective cohort survey study.