Dr. Sanjay Agarwala had started the research regarding management of AVN with bisphosphonate therapy and reported on it in 2001. Probably one of the only surgeons reporting in medical journal!
His index case was of a patient who refused any surgical intervention. Dr Agarwala analysed the cause of pain as collapse of bone due to weakness of the weakened bone. Weakened bone from osteoporosis was already being treated with bisphosphonates ! And therein lies the start of the story where legends spring from.
This pilot prescription of bisphosphonate therapy worked wonders and triggered off this methodological research at P.D. Hinduja National Hospital & Medical Research Centre. Bisphosphonates are poorly absorbed. At the best of times less than 1 % get absorbed from the GI tract. Hence daily intake is preferable in the first 3 to 6 months. The original treatment involved one tablet of Alendronate (10mg) to be taken on an empty stomach with two glasses of water.
For financial rather than medical reasons Pharma supported the dispensing of weekly dosage tablets 70 mg once weekly. Some formulations of 35 mg are also available. Keeping in mind that bisphosphonates are poorly absorbed in the GI tract, the current regimen advocates 35 mg tablets taken twice weekly. This ensures that the patient receives 70 mg on a weekly basis.
Bending forward or lying down or having food for 45 minutes after consumption of the tablet is to be avoided as the resultant acidic solution in the stomach can regurgitate and cause oesophagitis. Hence, patients are advised to take the tablet before brushing their teeth and the 45 mins are covered during the time of the morning rituals. Thereafter the patients can resume their normal daily activities and have tea/coffee, breakfast etc.
Recognising that there is poor absorption of oral bisphosphonates, hence poorer blood levels and hence slower efficacy , the current protocol includes an initial IV top up with 5 mg zolendronic acid. This ensures immediate blood levels of bisphosphonates, hence early response. The blood levels are maintained by the oral alendronate as described above. This particular regimen has been published internationally in the peer reviewed journal ‘Global oncology ‘.
Calcium and Vitamin supplementation are to be taken with bisphosphonate therapy for better efficacy.
This treatment needs to be continued for up to 3 years in view of the natural history to AVN being 3 years and the known safety profile of oral bisphosphonates which is for 3 years as well.
Patients were followed up with their clinical presentation and a radiological presentation including x-rays and MRI and their pain scores.
The Mechanism of action of Alendronate is described below :
- Critical ischemia Alendronate
- Necrosis
- Inflammatory response Anti- inflammatory
- Osteoclastic bone resorption Anti osteoclastic
Neo-osteogenesisThe results of the initial study was published in December 2001 in the Journal of the Association of Physicians in India and was honoured with the Best Paper Award and subsequently extended studies were published in Rheumatology Journal by 2005.
Dr. Sanjay Agarwala has published his 8 year follow-up in the JBJS, (British Journal of Bone and Joint Surgery -2009) and in 2011 the 10 year results were confirmed in JOA (Journal of Arthroplasty). These studies have shown 98% success rate in Stage I, 92% with Stage II and 70% with Stage III which is far better than various studies done in the past which had a success rate of only around 30%.
The cost involved for this treatment is a bare minimum of Rs. 150/- per month, which is affordable to the common man, and this avoids or postpones the requirement of total hip replacement surgery, the cost of which is very high.
This path breaking research on Bisphosphonate therapy in the management of AVN has paved the way for an economic mode of treatment while at the same time postponing or even avoiding the need for a hip replacement surgery.
This amazing discovery from an Indian surgeon, done with dogged persistence over 20 years, is now internationally acclaimed and cited in all legendary textbooks of Rheumatology and Orthopaedics. It has spawned new research in the previously difficult disease and is even used in paediatric conditions like Perthes disease.
Some patients who have advanced disease and who cannot or do not benefit from these methods can still have outstanding results by total hip replacements – THR. Patients can hope to be restored to their former functions within the ambit of norms for these artificial joints.
Continuing in the traditions of the surgical masters of legend like Sushruta, Indian surgical care is writing a new chapter in world literature.