Evaluation of a multimodal pain therapy concept for chronic pain after total knee arthroplasty: a pilot study in 21 patients

Mechanisms and Preventative Strategies for Persistent Pain following Knee and Hip Joint Replacement Surgery: A Narrative Review

Chronic postsurgical pain (CPSP) following total knee arthroplasty (TKA) and total hip arthroplasty (THA) is a prevalent complication of joint replacement surgery which has the potential to decrease patient satisfaction, increase financial burden, and lead to long-term disability. The identification of risk factors for CPSP following TKA and THA is challenging but essential for targeted preventative therapy. Recent meta-analyses and individual studies highlight associations between elevated state anxiety, depression scores, preoperative pain, diabetes, sleep disturbances, and various other factors with an increased risk of CPSP, with differences observed in prevalence between TKA and THA. While the etiology of CPSP is not fully understood, several factors such as chronic inflammation and preoperative central sensitization have been identified. Other potential mechanisms include genetic factors (e.g., catechol-O-methyltransferase (COMT) and potassium inwardly rectifying channel subfamily J member 6 (KCNJ6) genes), lipid markers, and psychological risk factors (anxiety and depression). With regards to therapeutics and prevention, multimodal pharmacological analgesia, emphasizing nonopioid analgesics like acetaminophen and non-steroidal anti-inflammatory drugs (NSAIDs), has gained prominence over epidural analgesia. Nerve blocks and local infiltrative anesthesia have shown mixed results in preventing CPSP. Ketamine, an N-methyl-D-aspartate (NMDA)-receptor antagonist, exhibits antihyperalgesic properties, but its efficacy in reducing CPSP is inconclusive. Lidocaine, an amide-type local anesthetic, shows tentative positive effects on CPSP. Selective serotonin reuptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs) have mixed results, while gabapentinoids, like gabapentin and pregabalin, present hopeful data but require further research, especially in the context of TKA and THA, to justify their use for CPSP prevention.

[Arthrofibrosis of the hip joint : Diagnostic and therapeutic challenge]

Arthrofibrosis is a frequent complication after total knee arthroplasty (TKA). Recently, arthrofibrosis could be successfully verified histologically after primary total hip arthroplasty (THA) and the clinical presentation on the hip could be described for the first time. Possible diagnostic and therapeutic approaches have not yet been published. The diagnostic work-up differs only slightly from that for the knee joint. Other causes, such as aseptic loosening, malalignment or periprosthetic joint infection should be excluded. The gold standard is still invasive diagnostics with histological evidence of arthrofibrosis according to the synovia-like interface membrane (SLIM) criteria. Conservative treatment approaches include mobilization under anesthesia and medication according to Traut, analogous to the knee joint. Surgical treatment should be carried out under strict interpretation of the indications and after detailed clarification for the patient. In contrast to the knee joint, open arthrolysis should be preferred to arthroscopic arthrolysis of the hip joint. It must be taken into consideration that the evidence for conservative as well as surgical treatment, including possible revision arthroplasty, cannot be assessed due to the absence of clinical data. Studies under controlled conditions on the possible treatment approaches in the presence of arthrofibrosis are desirable and necessary in order to be able to assess the significance of the symptoms. In addition to treatment, great importance should also be attached to the diagnostics. Histological confirmation of the diagnosis of arthrofibrosis should only be considered to a limited extent in the case of an assumed, only moderately successful surgical intervention.

Klinische Diagnostik, Differenzialdiagnostik, Pathogenese- und Stadienmodell der Arthrofibrose

Die Arthrofibrose (AF) gehört zu den häufigsten Komplikationen nach Verletzungen und operativen Eingriffen an Gelenken, v. a. nach Gelenk- und Kreuzbandersatz. Alle großen Gelenke können betroffen sein, am häufigsten ist es jedoch das Kniegelenk. Es kommt zur schmerzhaften Bewegungseinschränkung durch Vermehrung von fibrotischem Gewebe innerhalb und teilweise auch außerhalb des Gelenks. Der normale Heilungsprozess ist durch mechanische und emotionale Stressoren sowie starke Schmerzreize gestört. Die AF tritt zu 90 % schon wenige Tage nach der Verletzung oder Operation auf, sodass die Qualitätsstandards nicht erreicht werden können. Durch Physiotherapie und Rehabilitation kann oft keine wesentliche Verbesserung der Funktion erreicht werden, sodass die Aktivitäten des täglichen Lebens (ADL) stark eingeschränkt sind. Klinische Diagnostik, Differenzialdiagnostik sowie ein neues Pathogenese- und Stadienmodell der primären AF mit den daraus abgeleiteten therapeutischen Prinzipien werden vorgestellt.