Impact of post- amputation pain syndrome on the results of bone stump formation

Background. To the present day, a high rate of unsatisfactory amputation results still exists. The healing of the bone residual limb, the main support element of the residual limb, is of particular importance. Objective. To study the impact of postamputation pain syndrome on the nature of reparative processes in the bone residual limb. Methods. Three series of experiments were performed on 45 rabbits, 15 in each with mid-third thigh amputation and muscular plasty. In series 1 and 2, a perineural catheter was attached to the sciatic nerve stump during amputation, and mechanical irritation of the nerve was performed daily for 20 minutes in series 1 for 20 days. In series 2, 0.3 ml of 1% lidocaine was injected through the catheter into the circumference of the nerve twice daily for 20 days. Animals of series 3 served as a control. The follow-up periods were 1, 3, 6 months. The study method was histological with infusion of the vessels with ink-gelatin mixture. Results. In series 1, there was a sharp disturbance of the reparative process, which consisted in shape changes, resorption of the cortical diaphyseal plate, stump deformity, absence of bone closure plate formation, and microcirculatory disturbances. In most experiments of the 2nd series, organotypic stumps were formed with normalized microcirculation. In series 3, the results of the residual limb formation were better than in series 1, but worse than in series 2. Conclusion. In the absence of pain syndrome, the bone stump after amputation at the diaphysis level over a period of 1, 3, 6 months retains its cylindrical shape, the structure of the cortical diaphyseal plate, the content of the medullary canal with normal microcirculation, the formation of the bone closure plate, and the completion of the reparative process. The presence of postamputation pain syndrome in the stump distorts the course of the reparative process with the development of pathological remodeling of bone tissue.

Peripheral Nerve Stimulation in Pain Management: A Systematic Review

BACKGROUND: Peripheral nerve stimulation (PNS) has been increasingly used to manage acute and chronic pain. However, the level of clinical evidence to support its use is not clear. OBJECTIVES: To assess the clinical evidence of PNS in the treatment of acute or chronic pain. STUDY DESIGN: A systematic review of the efficacy and safety of PNS in managing acute or chronic pain. METHODS: Data sources were PubMed, Cochrane Library, Scopus, CINAHL Plus, Google Scholar, and reference lists. The literature search was performed up to December 2019. Study selection included randomized trials, observational studies, and case reports of PNS in acute or chronic pain. Data extraction and methodological quality assessment were performed utilizing Cochrane review methodologic quality assessment and Interventional Pain Management Techniques–Quality Appraisal of Reliability and Risk of Bias Assessment (IPM-QRB) and Interventional Pain Management Techniques–Quality Appraisal of Reliability and Risk of Bias Assessment for Nonrandomized Studies (IPM-QRBNR). The evidence was summarized utilizing principles of best evidence synthesis on a scale of 1 to 5. Data syntheses: 227 studies met inclusion criteria and were included in qualitative synthesis. RESULTS: Evidence synthesis based on randomized controlled trials (RCTs) and observational studies showed Level I and II evidence of PNS in chronic migraine headache; Level II evidence in cluster headache, postamputation pain, chronic pelvic pain, chronic low back and lower extremity pain; and Level IV evidence in peripheral neuropathic pain, and postsurgical pain. Peripheral field stimulation has Level II evidence in chronic low back pain, and Level IV evidence in cranial pain. LIMITATIONS: Lack of high-quality RCTs. Meta-analysis was not possible due to wide variations in experimental design, research protocol, and heterogeneity of study population. CONCLUSIONS: The findings of this systematic review suggest that PNS may be effective in managing chronic headaches, postamputation pain, chronic pelvic pain, and chronic low back and lower extremity pain, with variable levels of evidence in favor of this technique. KEY WORDS: Acute pain, chronic pain, neuromodulation, peripheral nerve stimulation

Surgical Treatment of Symptomatic Neuromas After Lower Limb Amputations

Summary. The pain after amputations is a global problem of modern medicine. There are three distinct clinical entities that can form the postamputation pain: phantom limb pain (PLP), phantom sensations (PSs), and residual limb pain (RLP). PLP and PSs are pathophysiological phenomena, which need complex conservative treatment. RLP is a local condition that arises from neuroma, excessive scarring, osteophites, etc. and can be resolved by surgery. Objective: to analyze the results of surgical treatment of patients with symptomatic neuromas after lower limb amputations (LLA). Materials and Methods. The study included 43 patients with symptomatic neuromas 3–10 years after LLA. There were 40 male and 3 female patients (mean age 33.9±3 years). Amputations were caused by trauma (33 cases), mine-blast injury (7 cases), diabetes (1 case), and oncology (2 cases). The level of amputation was thigh (3 cases), knee (1 case), and ankle (39 cases). The pain intensity was measured by the VAS (Visually Analog Scale) and prosthesis using by the ALAC (Artificial Limb and Appliance Centre, USA) scale. Results. RLP had 43 patients (100%), PLP – 8 (8.6%), and PSs – 35 (81.4%) patients. The average level of pain was 7.4±0.9. Prosthesis was used in 74.4% (32 patients), but 11 of them used prosthesis for cosmetic or transportation reasons (levels I and II by the ALAC scale). Complications after surgery were presented by hematoma (3 cases), marginal skin necrosis (2 cases), and tearing of m. gastrocnemius from the tibia after the fall on the stump (1 case). The results were assessed in 35 patients in terms from 1 to 15 years. The pain severity decreased from 7.4±0.9 to 3.2±0.6 (p˂0.05; two-sample t-test). The number of RLP cases decreased to 11 (31.4%), but the number of PLP and PSs cases did not significantly change (PLP – 5 cases or 14.3%; PSs – 27 cases or 77.1%). The prosthesis using rised to 100% due to functionality (III–VI levels by the ALAC scale). Conclusions. Surgical method is the main treatment of symptomatic neuromas after LLA. The surgery must expect proximal neurotomy and, if need, reamputation and stump reconstruction. This approach helps to reduce pain and improves the functional ability of persons with LLA.