Introduction

Samprapti, also known as pathogenesis, refers to the development of a disease. It details the entire process, beginning with causative factors to exposure of disease.^[1]

These factors cause initial disturbances in the body and mind, eventually leading to the production of premonitory symptoms and the disease itself. This allows healthcare professionals to identify, name and diagnose the illness. Though Vata is one of the three fundamental Doshas^[2], it is responsible for a greater number of diseases compared to Pitta and Kapha combined.^[3]

Vatavyadhi (Diseases occur due to vitiation of Vata dosha) is a significant ailment categorized as one among eight major diseases Ashtamahagada (Eight major diseases).^[4] Sandhigata Vata, a specific joint disorder arising from aggravated Vata, is extensively elaborated upon in classic Ayurvedic texts under Vatavyadhi. This condition remains a significant health concern in modern times. The contemporary lifestyle characterized by stress, irregular food habits and physical exertion exacerbates Vata imbalance, leading to a surge in Sandhigata Vata cases. This condition significantly impacts daily life, particularly in the old age, often resulting in disability. Classical Ayurvedic texts describe the characteristic signs and symptoms of Sandhigata Vata as Vata Poornadhrithi Sparsha (on palpation joint appears as leather bag inflated with air), Sandhi Shotha (oedema of joints), Prasarana-Akunchana Vedana (pain while making efforts for extensions and contraction of joints)^[5], Hanti Sandhi (Diminution of movement of joints), Sandhi Shoola (Pain in joints)^[6] and Sandhi Atopa (crepitus in joints).^[7] Sandhigata Vata shares striking similarities with osteoarthritis. Osteoarthritis is a degenerative joint disease characterized by the breakdown of cartilage, leading to stiffness, swelling, pain and reduced mobility.^[8]

This condition has become increasingly prevalent, affecting over 528 million people globally in 2019, an increase of 113% since 1990, with a notable increase since 1990. The knee is the most commonly affected joint, with 365 million individuals experiencing osteoarthritis in this area. Women and older adults are majorly impacted, with 60% of patients being female and 73% aged over 55.^[9]

it disrupts normal function of that particular site, this condition is known as Gatavata.^[13]

Gata- situated in or gone to any state or condition or fallen into.

When Doshas are in a state of imbalance due to an underlying pathological condition they exhibit aberrant patterns in their movement, distribution, localization and manifestation within the body. This irregular behaviour is a hallmark of disease and distinguishes it from the normal, harmonious state of the Doshas.

Sandhigata Vata

Common causes include factors such as excessive physical exertion, irregular daily routines, exposure to cold and windy environments, consumption of dry and light foods, lack of proper rest, obesity etc. These factors can disrupt the balance of Vata Dosha in the body, leading to imbalance in Vata Dosha^[14] which vitiates Asthi, as Asthi is the Ashraya for Vata Dosha.

General pathogenesis of Vatavyadhi is outlined in Ayurvedic literature as, aggravated Vata caused by depletion of Dhatu occupies empty channels in the body, leading to localized or generalised ailments.^[15]Other author further opines on this by explaining that Dhatukshaya (depletion of Dhatu) creates these empty channels, allowing Vata to circulate freely, does accumulation and obstruction, ultimately disrupting normal function.^[16]

The pathogenesis of Sandhigata Vata can likely be understood within this framework by understanding two ways of aggravation of Vata they are Dhatukshayajanya (due to depletion of Dhatu) and Margavarodhajanya (due to obstruction of channels). Dhatukshayajanya Samprapti of Sandhigata Vata / Nirupastambhita Sandhigata Vata: Dhatu nourishes and sustains the body.

By various aetiology Kshaya(depletion) of Dhatu will be seen. Mostly in old age, Vata predominance occurs with decreased and impaired Agni (digestive and metabolic fire) further leads to depletion of Dhatus quantitatively and qualitatively. As Kapha is decreased the Shleshaka Kapha which resides in joints and Shleshmadhara Kala also get affected and corresponds to depletion of Asthisandhi. This depletion of Dhatu leads to aggravation of Vata give rise to further depletion of Sandhi.

Discussion

As vitiated Vata alone isn't directly involved in Sandhigata Vata, it's not described under the 80 types of Nanatmaja Vikara of Vata. However, it's elaborated upon in the context of Vatavyadhi Chikitsa. It is possible that the role of Vyana vayu is crucial in categorizing Sandhigata Vata under Vatavyadhi. The exact cause of Sandhigata Vata isn’t mentioned, but factors causing Vatavyadhi and Asthi Sroto Dushti (bone channel vitiation) can be considered. Various causative elements lead to the aggravation of Vata which occurs through processes such as Dhatukshaya (tissue depletion) and Margavarodha (channel blockage) ultimately resulting in Sandhigata Vata.

This degeneration leads to increased bone hardness, a condition referred to as sclerosis, which may contribute to osteoporosis. This sequence of events can be hypothetically characterized as Tarunasthi Dhatukshaya in older adults, subsequently leading to further aggravation of Vata due to the interplay of Ashraya-Ashrayi Bhava. A study exploring the intersection of aging and inflammation in osteoarthritis has suggested that the condition was once understood solely as cartilage degradation. However, contemporary understanding recognizes the involvement of inflammaging originating from the synovium, cartilage, and subchondral bone. Inflammaging, a term describing chronic, low-grade inflammation associated with aging, contributes to osteoarthritis by elevating levels of reactive oxygen species and inflammatory cytokines, which are linked to age-related diseases such as cancer and diabetes. Both innate and adaptive immune responses are activated, resulting in increased cytokines that damage cartilage. Additionally, antigens from damaged joints can activate inflammasomes, while aging can impair the regulatory functions of B and T lymphocytes, exacerbating self-reactivity and worsening joint damage.^[18] For individuals who lead a sedentary lifestyle and are obese Srotoavarodha (channel obstruction) by Meda may lead to vitiation of Vata, which adversely affects the bones and aggravates Vata. Studies investigating the onset of osteoarthritis in sedentary adults have established that a lack of physical activity contributes to a phenomenon known as stagnant cartilage syndrome. This term reflects the difficulties associated with maintaining thick cartilage under physiological stress. The hypothesis suggests that physical inactivity can foster knee osteoarthritis by creating a stagnant diffusion barrier at the synovial fluid-cartilage interface, which can limit the nutrient supply and promote waste accumulation, thus disrupting cellular homeostasis and leading to progressive tissue degradation.^[19] In acute cases of Sandhigata Vata the typical stages of Sanchaya (accumulation), Prakopa (aggravation) and Prasara (manifestation) may be expedited resulting in a more rapid manifestation of the disease. Conversely, in slow and chronic conditions while Vata aggravation may occur still it may not be sufficient to elicit the clinical symptoms associated with Sandhigata Vata. Vata as a Dosha, is fundamentally associated with Gatyatmak (movement).

By accurately diagnosing the specific pathway through which Sandhigata Vata has developed, Ayurvedic physicians can employ targeted therapeutic strategies, ultimately enhancing the quality of life for individuals afflicted with this condition

Acknowledement

I express my deepest gratitude to my guide, Dr. Pramod Shet B, and co-guide, Dr. Rashmi Kalkura K, for their constant encouragement, invaluable support throughout the PG curriculum and unwavering guidance. I am also profoundly grateful to the CCRAS PG Star programme for their generous financial assistance.

References