Presumptive Long Rod Technique (PLRT) for Revision Extension Instrumented Spine Surgery: A Technical Note

Volume 3 | Issue 2 | October 2022-March 2023 | page: 119-124 | Ajay Krishnan, Shivakumar A Bali, Devanand Degulmadi, Shivanand Mayi, Ravi Ranjan, Vatsal Parmar, Pranav Charde, Vikrant Chauhan, Mirant B Dave, Denish Patel, Preety A Krishnan, Bharat R Dave


Authors: Ajay Krishnan [1], Shivakumar A Bali [1], Devanand Degulmadi [1], Shivanand Mayi [1], Ravi Ranjan [1], Vatsal Parmar [1], Pranav Charde [1], Vikrant Chauhan [1], Mirant B Dave [1], Denish Patel [1], Preety A Krishnan [2], Bharat R Dave [1]

[1] Department of Spine Surgery, Stavya Spine Hospital & Research Institute, Mithakhali, Ellisbridge, Ahmedabad, Gujarat, India.
[2] Department of Radiology, Stavya Spine Hospital & Research Institute, Mithakhali, Ellisbridge, Ahmedabad, Gujarat, India.

Address of Correspondence

Dr. Ajay Krishnan,
Spine Surgeon, Department of Spine Surgery, Stavya Spine Hospital & Research Institute, Mithakhali, Ellisbridge, Ahmedabad, Gujarat, India.


Background: Revision spine surgery needing extension of fixation either require complete exposure of previously operated levels for rod exchange or can be managed by linking the new surgical construct (NSC) to primary surgical construct (PSC) with dominos. Presumptive long rod technique (PLRT) provides additional length of rod for domino placement.
Case report: 80-year male on conservative management developed acute cauda equina syndrome retention due to pre-existing multilevel lumbar stenosis and acute big sequestrated disc prolapse at L12. Emergent surgical intervention in form of L1 to L4 pedicle screw fixation with postero-lateral bone grafting and fragmentectomy was done. Peri-operative period was uneventful. He was started on Teriperatide 20mcg daily with progressive mobilization and physiotherapy. At 4 months of follow-up, he developed L1 osteoporotic fracture with proximal junctional kyphosis (PJK). Patient underwent T12-L1 interbody fusion with extension of fixation to T10 which required complete opening up of previous incision as it was an Indian implant set. A domino of larger foot print couldn’t be accommodated in the space available between L1- L2 screws. Owing to severe osteoporosis and degenerative changes at proximal levels, presumptive oversized rods were inserted with extra lengths of the rods left at proximal ends. This technique is labelled PLRT(presumptive long rod technique) at our institute. At 6 months of follow up, patient developed T10 osteoporotic fracture with PJK and patient was planned for extension of fixation upto T4. Since the extra lengths of rods were available at proximal ends, only the planned operative levels were exposed and it was connected to previous construct using the larger footprint domino. Patient improved clinically and was ambulatory. The patient expired at 18 months due to cardio-respiratory arrest unrelated to the spinal events.
Conclusion: Additional rod lengths intentionally left at adjacent levels during primary surgery where there is anticipation of PJK and adjacent segment disease (ASD) can be a boon when there is need for extension of fixation. These extra lengths of rod can be used to place dominos and connect PSC to NSC without the need for exposure of PSC levels for rod exchange, preventing complications especially in setups with economic constraints.
Keywords: Complex, Adult Spinal Deformity, Adjacent Segment, Junctional Kyphosis, Osteoporosis, Revision, Surgery, Multirod.


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How to Cite this Article: Krishnan A, Bali SA, Degulmadi D, Mayi S, Ranjan R, Parmar V, Charde P, Chauhan V, Dave MB, Patel D, Krishnan PA, Dave BR | Presumptive Long Rod Technique (PLRT) for Revision Extension Instrumented Surgery: A Technical Note | Back Bone: The Spine Journal | October 2022-March 2023; 3(2): 119-124.

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Inter-relation of Hypocalcemia with Established Osteoporosis and DXA Analysis – A Prospective Study of 100 Indian Subjects

Volume 1 | Issue 1 | October 2020-March 2021 | page: 19-22  | Bharat R. Dave, Himanshu Kulkarni, Devanand Degulmadi, Shivanand Mayi, Ravi Ranjan Rai, Kirit Jadav, Ajay Krishnan

Authors: Bharat R. Dave [1], Himanshu Kulkarni [1], Devanand Degulmadi [1], Shivanand Mayi [1], Ravi Ranjan Rai [1], Kirit Jadav [1], Ajay Krishnan [1]

[1] Stavya Spine Hospital and Research Institute, Near Nagari Eye Hospital, Mithakhali, Ellisbrige, Ahmedabad, Gujarat, India .

Address of Correspondence
Dr. Ajay Krishnan,
Stavya Spine Hospital and Research Institute, Ahmedabad, Gujarat, India .


Purpose: The purpose of the study was to screen the presence of hypocalcemia and clinical signs specific to hypocalcemia in dual-emission X-ray absorptiometry proven osteoporotic patients and also to analyze variations of T scores at specific anatomical regions in lumbar spine and hip.
Type: Prospective cohort.
Materials and Methods: One hundred patients who had T score of <−2.5 at any of the lumbar levels or in total lumbar T score were selected. Ionic calcium levels (normal – 1.1–1.135 mmol/L) of each patient were calculated. Trousseau’s sign and Chvostek’s sign were checked. Analysis of T scores was done for each patient.
Results: Twelve out of 100 patients had hypocalcemia. Out of whom, only one patient had positive Trousseau’s sign and none had Chvostek’s sign present. In normocalcemic patients (n = 88), seven patients had positive Trousseau’s sign and three had Chvostek’s sign present. Average total lumbar T score of 100 patients was −3.0 (±1.1 SD). After calculating the averages, the L3 had least T score of −3.3 (±0.9 SD) and L1 had highest T score of −2.5 (±1.3 SD), respectively. Twenty-seven patients had total hip T scores <−2.5 and 72 patients had T scores <−2.5 at Ward’s triangle. Similarly, average total hip T score of 100 patients was −2.0 (±1.6 SD); average T score at Ward’s angle was much lower at −2.9 (±1.4SD).
Conclusion: L3 vertebra and Ward’s triangle are most sensitive indicators of osteoporosis. Although theoretically unlikely, hypocalcemia can be present in osteoporotic patients. Trousseau’s sign and Chvostek’s sign may be present in patients with established hypocalcemia; however, their absence does not rule out the diagnosis.
Keywords: Osteoporosis, hypocalcemia, T score, ward’s triangle.



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How to Cite this Article: Dave BR, Kulkarni H, Degulmadi D, Mayi S, Rai RR, Jadav K, Krishnan A| Inter-relation of Hypocalcemia with Established Osteoporosis and DXA Analysis – A Prospective Study of 100 Indian Subjects | Back Bone: The Spine Journal | October 2020-March 2021; 1(1): 19-22.


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