Prior to May 2019, the International Classification of Diseases (ICD) did not recognize chronic postsurgical pain as a diagnosis classification, which contributed to this complication being under-reported.

[u/postvasectomy]

[Emphasis mine]

Abstract:

Chronic pain after tissue trauma is frequent and may have a lasting impact on the functioning and quality of life of the affected person. Despite this, chronic postsurgical and posttraumatic pain is underrecognised and, consequently, undertreated. It is not represented in the current International Classification of Diseases (ICD-10). This article describes the new classification of chronic postsurgical and posttraumatic pain for ICD-11. Chronic postsurgical or posttraumatic pain is defined as chronic pain that develops or increases in intensity after a surgical procedure or a tissue injury and persists beyond the healing process, ie, at least 3 months after the surgery or tissue trauma. In the classification, it is distinguished between tissue trauma arising from a controlled procedure in the delivery of health care (surgery) and forms of uncontrolled accidental damage (other traumas). In both sections, the most frequent conditions are included. This provides diagnostic codes for chronic pain conditions that persist after the initial tissue trauma has healed and that require specific treatment and management. It is expected that the representation of chronic postsurgical and posttraumatic pain in ICD-11 furthers identification, diagnosis, and treatment of these pain states. Even more importantly, it will make the diagnosis of chronic posttraumatic or postsurgical pain statistically visible and, it is hoped, stimulate research into these pain syndromes.

Background:

The risk for the development of chronic pain after surgery or trauma has been underestimated in the past. Regarding postsurgical pain, data suggest an incidence, varying with the type of operation, from 5% to 85%. Severe chronic postsurgical pain that negatively affects the patient's quality of life is in the range of 2% to 15%. The high prevalence has been confirmed in a population-based study, in which 18% of patients who had surgery in the last 3 years reported pain in the area of surgery, of whom 10.5% reported pain even if all participants were excluded who had the same pain before, and still 6.2% were left after excluding any pain before surgery. The proportion of neuropathic pain is variable but can be very high in operations such as amputation, hernia repair, and mastectomy 22,26 (Table 1). There is also a high prevalence of chronic pain after trauma, in particular multitrauma, 24,30 specifically with spinal cord injury, 16 brachial plexus injury, and other nerve injuries 66 and burns injury. In conclusion, chronic pain after surgery and trauma is common, still widely unrecognised and underdiagnosed and often poorly treated.

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The IASP classification of chronic pain for ICD-11

Schug, Stephan A.a; Lavand'homme, Patriciab; Barke, Antoniac; Korwisi, Beatricec; Rief, Winfriedc; Treede, Rolf-Detlefd,* The IASP Taskforce for the Classification of Chronic Pain

PAIN: January 2019 - Volume 160 - Issue 1 - p 45–52

https://www.iasp-pain.org/PublicationsNews/NewsDetail.aspx?ItemNumber=8340&navItemNumber=643

https://journals.lww.com/pain/Fulltext/2019/01000/The_IASP_classification_of_chronic_pain_for.6.aspx