Board-Certified Neurosurgeon · FAANS

When Surgery
Needs to Be
Done Right.

John M. Caridi, MD, MBA, FAANS — fellowship-trained spine neurosurgeon with specialized expertise in complex spinal deformity, revision surgery, and cases other surgeons find challenging. Practicing at Spinal Associates in New York City.

Dr. John M. Caridi, MD — Spine Neurosurgeon
20+
Years Experience
108
Publications
Fellowship
Trained
NYC
Spinal Associates
National Referral Center
Complex Revision & Deformity Surgery — Sought Out When Prior Surgery Has Failed
20+
Years Experience
108
Publications
Top 3
Academic Centers

A Career Dedicated
to the Spine

MD — Indiana University

BS — University of Notre Dame

MBA — Columbia University & London Business School

Healthcare leadership & strategy

Fellowship — Munich, Germany

Advanced minimally invasive spine surgery

Hospital for Special Surgery

Orthopedic Spine & Scoliosis Fellowship

Dr. John M. Caridi is a board-certified, fellowship-trained neurosurgeon and spine specialist practicing at Spinal Associates in New York City. He is recognized nationally as an expert in complex spinal deformity correction and revision spine surgery — the most technically demanding categories in all of spine surgery, requiring advanced training, precise judgment, and extensive experience that most spine surgeons do not possess.

Patients travel from across the country to see Dr. Caridi after prior surgeries have failed to provide relief, or when they have been told their case is "too complex" for a local surgeon. He has directed Spine Deformity programs at three of the nation's top academic medical centers — Mount Sinai, UT Health Houston, and Northwell Health — and has served as Chief of Spine and Vice Chair of Quality. He has trained the next generation of spine surgeons as a fellowship director and medical educator.

Dr. Caridi's research spans over 108 peer-reviewed publications, with pioneering work in machine learning applications for surgical outcomes, adult spinal deformity, and minimally invasive techniques. He is an Associate Editor of Spine Deformity and actively serves on national committees for the Scoliosis Research Society and AANS/CNS.

"When a patient comes to me after a prior surgery has failed, my job is to understand exactly what went wrong and give them a clear, honest plan to fix it — with the same precision I would want for my own family."

— John M. Caridi, MD, MBA, FAANS

Procedures & Treatments

Comprehensive surgical solutions for the full spectrum of spinal conditions. Dr. Caridi is sought out nationally for his expertise in revision spine surgery and complex spinal deformity correction — taking on the cases other surgeons find most challenging.

Anterior Cervical Discectomy & Fusion (ACDF)

Removal of a herniated or degenerated cervical disc through a small incision at the front of the neck, followed by fusion of the adjacent vertebrae to restore stability and relieve nerve compression.

Radiculopathy Myelopathy Disc Herniation Stenosis
Patient Guide

When Is It Recommended?

ACDF is indicated when cervical radiculopathy, myelopathy, or disc herniation fails to respond to conservative care (physical therapy, medications, injections) — or when neurological deficits are progressing. Common conditions include pinched nerve roots, spinal cord compression, and cervical instability from trauma.

What to Expect

Surgery takes 1–2 hours per level. Most patients go home the same day or after one night. Full recovery typically takes 4–6 weeks. A cervical collar is worn for 4–6 weeks while fusion occurs. 90–95% of patients experience significant relief of arm pain and neurological symptoms.

Imaging

Normal cervical spine MRI
Normal Cervical Spine
Cervical disc herniation
Cervical Disc Herniation
Post-operative ACDF X-ray
Post-Operative ACDF

Cervical Laminectomy & Fusion

Posterior decompression of the spinal cord by removing the lamina across multiple cervical levels, combined with instrumented fusion for stability — the definitive treatment for severe cervical myelopathy.

Myelopathy Spondylotic Cord Compression Ossified Ligament Cervical Stenosis
Patient Guide

Who Needs This Procedure?

Cervical myelopathy — compression of the spinal cord itself — causes hand clumsiness, leg weakness, balance problems, and in severe cases, bowel or bladder dysfunction. Unlike radiculopathy (pinched nerve), myelopathy rarely improves on its own and can become permanently disabling without surgery.

What to Expect

The lamina (bony roof) is removed to create space for the spinal cord, and the vertebrae are fused with rods and screws to prevent instability. Patients typically walk the first day post-op; hospital stay is 2–3 nights. A cervical collar is worn for 6–12 weeks. Most patients experience arrest of progression and meaningful functional recovery.

Imaging

Cervical stenosis MRI
Cervical Stenosis
Post-operative posterior cervical fusion
Post-Operative Fusion

Posterior Cervical Laminoplasty

A motion-preserving alternative to laminectomy — the lamina is reshaped and hinged open to expand the spinal canal without removing it, ideal for multilevel cervical myelopathy in patients with preserved cervical lordosis.

Myelopathy Multilevel Stenosis Ossified Ligament Motion Preserving
Patient Guide

Laminoplasty vs. Laminectomy

Rather than removing the lamina entirely, laminoplasty creates a hinge on one side and opens the lamina like a door, securing it in the open position with a small plate. This expands the spinal canal while preserving the posterior bony architecture — reducing the risk of postoperative instability and maintaining more natural neck motion.

What to Expect

Surgery takes 2–3 hours. Hospital stay is typically 2 nights. A soft cervical collar is worn for 4–6 weeks. Patients typically walk the first day post-op. Neck stiffness is expected and improves with physical therapy. Most patients see symptom stabilization or improvement within 3–6 months.

Imaging

Pre-operative cervical stenosis
Pre-Op: Stenosis
Post-operative laminoplasty
Post-Op: Laminoplasty
★ Area of Specialization

Cervical Revision Surgery

Corrective surgery for patients whose prior cervical procedure did not achieve the intended outcome — including pseudoarthrosis after ACDF, adjacent segment disease, failed disc replacement, and iatrogenic cervical kyphosis.

Pseudoarthrosis Hardware Failure Adjacent Segment Disease Kyphosis Correction
Patient Guide

Why Prior Surgery May Fail

The four most important causes of failure after cervical surgery are: pseudoarthrosis (failure of bone fusion), iatrogenic cervical kyphosis, failed disc replacement, and adjacent segment disease. Each has a distinct mechanism and requires a targeted surgical solution. Dr. Caridi has specialized expertise in the diagnosis and correction of all four.

Dr. Caridi's Approach

Revision cases require comprehensive review of prior operative reports, imaging, and implant records before a plan is formed. Dr. Caridi will explain clearly what went wrong previously and what corrective steps are proposed — so you can make a fully informed decision. Bring all prior surgical records and imaging to your consultation.

Imaging

Cervical adjacent segment disease
Adjacent Segment Disease After Prior Cervical Fusion

Craniocervical Junction Surgery

Surgical management of pathologies at the skull-cervical junction — including Chiari malformation, atlantoaxial instability, rheumatoid pannus, and os odontoideum — one of the most anatomically demanding regions of the spine.

Chiari Malformation Atlantoaxial Instability Rheumatoid Pannus Os Odontoideum
Patient Guide

Why This Region Is Unique

The craniocervical junction houses the brainstem, upper cervical cord, vertebral arteries, and upper cranial nerves in a remarkably confined space. Pathology here — from Chiari malformation to atlantoaxial instability — can produce devastating consequences if unrecognized or untreated. The central surgical question is always: is decompression alone sufficient, or is fusion also required?

Chiari Malformation Decompression

Posterior fossa decompression relieves compression of the brainstem and spinal cord by removing bone at the back of the skull and expanding the dural covering. Surgery takes 2–3 hours; hospital stay is 2–4 nights. 85–95% of patients experience meaningful symptom relief.

Imaging

Chiari malformation MRI
Chiari Malformation — MRI

Lumbar Microdiscectomy

Microsurgical removal of the herniated disc fragment pressing on a lumbar nerve root — the most common and highly successful spine surgery for sciatica and lower extremity radiculopathy, performed through a minimal incision.

Sciatica Disc Herniation Radiculopathy Foot Drop
Patient Guide

When Is It Recommended?

Surgery is typically considered after at least 6 weeks of conservative care (physical therapy, anti-inflammatories, epidural injections) has failed — or when progressive weakness, foot drop, or cauda equina syndrome is present. Most commonly affects L4–5 or L5–S1 levels.

What to Expect

Surgery takes about 1 hour through a 1-inch incision. Most patients go home the same day. Return to light activity in 1–2 weeks; full recovery in 4–6 weeks. Success rate for leg pain relief is approximately 90%. The disc can re-herniate in 5–10% of cases, which is why core strengthening rehabilitation is essential.

Imaging

Lumbar disc herniation sagittal MRI
Disc Herniation — Sagittal
Lumbar disc herniation axial MRI
Disc Herniation — Axial

Lumbar Spinal Stenosis Surgery

Surgical decompression of the lumbar spinal canal to relieve nerve compression from bone spurs, thickened ligaments, and disc bulging — restoring the ability to walk and stand without pain.

Neurogenic Claudication Spinal Canal Narrowing Leg Pain & Weakness Decompression
Patient Guide

Understanding Lumbar Stenosis

Stenosis causes the spinal canal to narrow due to a combination of disc degeneration, bone spur formation, facet joint enlargement, and ligamentum flavum thickening. The signature symptom is neurogenic claudication — pain, cramping, or weakness in the legs when walking, relieved immediately by sitting or bending forward. Most commonly affects L4–5.

Surgical Decompression

A lumbar laminectomy removes the bone and thickened ligament compressing the nerves. When instability is present, fusion is added. Surgery takes 1–3 hours depending on levels involved. Most patients walk the same day. Return to normal activity in 4–8 weeks. Over 80% of patients achieve significant, durable relief of leg symptoms.

Imaging

Normal lumbar spine MRI
Normal Lumbar Spine
Lumbar stenosis MRI
Lumbar Stenosis

Lumbar Spondylolisthesis Surgery

Surgical stabilization for vertebral slippage in the lumbar spine — decompressing the nerves compressed by the slip and fusing the unstable segment to prevent further progression and relieve back and leg pain.

Vertebral Slippage Spinal Instability Degenerative Interbody Fusion
Patient Guide

What Is Spondylolisthesis?

Spondylolisthesis occurs when one vertebra slips forward over the one below it, most commonly L4 on L5. The slip stretches and compresses nerves, causes stenosis, and destabilizes the disc and facet joints. Graded I–IV based on the percentage of slip; Grade I (0–25%) is most common and often managed conservatively. Grades II–IV typically require surgical consideration.

Surgical Treatment

Surgery involves decompressing the nerve roots and fusing the slipped vertebrae with a bone graft and pedicle screw instrumentation (using a posterior or transforaminal interbody fusion approach). Recovery involves 2–3 nights in hospital, a lumbar brace for 6–8 weeks, and physical therapy starting at 4–6 weeks. Over 85% of patients achieve significant relief of leg and back symptoms.

Imaging

Lumbar spondylolisthesis
Lumbar Spondylolisthesis — L4 on L5
★ Area of Specialization

Lumbar Revision Fusion Surgery

Corrective surgery for lumbar fusion that has failed to heal, hardware that has loosened or broken, or new problems that have developed at adjacent spinal levels — requiring specialized expertise in complex reconstruction.

Pseudoarthrosis Hardware Failure Adjacent Segment Disease Flatback
Patient Guide

Why Lumbar Fusion May Fail

The three most common causes of failure are: pseudoarthrosis (the bone graft never healed, leaving a painful false joint), iatrogenic flatback deformity (excessive straightening of the lumbar curve causing forward lean and chronic pain), and adjacent segment disease (accelerated degeneration above or below the fusion). Each requires a distinct surgical correction.

Dr. Caridi's Approach

Revision surgery demands comprehensive review of prior records, imaging, and implant documentation before any plan is formed. Bring all prior surgical records to your consultation. Dr. Caridi will explain precisely what failed and what corrective approach is recommended.

Imaging

Adjacent segment disease after lumbar fusion
Adjacent Segment Disease After Prior Fusion
★ Area of Specialization

Flatback Deformity Correction

Surgical restoration of lumbar lordosis (the spine's normal inward curve) for patients with sagittal imbalance — correcting the forward-leaning posture that causes chronic pain, exhaustion, and loss of function.

Sagittal Imbalance Lumbar Hypolordosis Osteotomy Deformity Correction
Patient Guide

What Is Flatback Deformity?

The healthy lumbar spine has a gentle inward curve (lordosis) that keeps the body balanced over the hips and ankles. When this curve is lost — from degenerative disease, prior surgery, or aging — patients must compensate by bending their knees and thrusting their hips forward, a constant exhausting fight against gravity. The sagittal vertical axis (SVA) measures alignment; normal is less than 5 cm.

Surgical Correction

Correction involves osteotomies (controlled bone cuts) to recreate lordosis, combined with instrumented fusion to hold the corrected alignment. This is among the most complex procedures in spine surgery. Recovery spans several months with supervised physical therapy. Outcomes can be life-changing — patients stand upright and walk without exhaustion for the first time in years.

Imaging

Flatback deformity imaging
Flatback Deformity — Sagittal Imbalance

Intradural Spinal Tumor Resection

Microsurgical removal of tumors arising within the dural sac — including schwannomas, meningiomas, ependymomas, and astrocytomas — the majority of which are benign and curable with complete resection.

Schwannoma Meningioma Ependymoma Intramedullary
Patient Guide

Extramedullary vs. Intramedullary

The critical distinction is whether the tumor is outside the spinal cord (extramedullary — 65–70% of intradural tumors) or within the cord itself (intramedullary — 25–30%). Extramedullary tumors such as schwannomas and meningiomas are usually benign, displace the cord without invading it, and are highly curable with complete resection. Intramedullary tumors arise from cord tissue and are more surgically challenging.

Surgical Outcomes

Intradural spinal tumors are among the most surgically rewarding conditions to treat — complete resection often produces dramatic recovery of neurological function, particularly when treated before irreversible cord injury occurs. Intraoperative neurophysiologic monitoring (motor and sensory evoked potentials) is used throughout to protect neurological function.

Imaging

Intradural spinal tumor MRI
Intradural Spinal Tumor — MRI

Spine Health & Conservative Care

Comprehensive education on back pain prevention, spine-healthy body mechanics, and targeted exercise — most back pain can be prevented and managed without surgery through the right habits and care.

Back Pain Body Mechanics Exercise Prevention
Patient Guide

Dr. Caridi's Philosophy

Surgery is always the last resort. Back pain affects up to 80% of people at some point in their lives, yet the vast majority respond well to conservative care — physical therapy, targeted exercise, ergonomic adjustments, and medications. Dr. Caridi always exhausts non-surgical options before recommending an operation.

Conservative Care First

The spine health guide covers proper lifting mechanics, ergonomic workstation setup, sleeping positions, core strengthening exercises, and strategies for managing flare-ups. Download the free guide to learn how to protect your spine and reduce the risk of surgery.

Downloadable Patient Guides

These comprehensive guides — written by Dr. Caridi — explain each procedure in plain language. Download, print, and bring questions to your appointment.

ACDF Patient Brochure

Complete guide to Anterior Cervical Discectomy & Fusion — indications, surgical steps, recovery timeline, and what to expect at home.

Download PDF

Cervical Laminectomy & Fusion

Understanding cervical myelopathy and the posterior decompression + fusion procedure that treats severe spinal cord compression in the neck.

Download PDF

Posterior Cervical Laminoplasty

How laminoplasty expands the spinal canal while preserving motion — a detailed guide for patients with multilevel cervical cord compression.

Download PDF

Cervical Revision Surgery Guide

Why cervical spine surgery can fail and what can be done — covering pseudoarthrosis, adjacent segment disease, hardware failure, and kyphosis correction.

Download PDF

Craniocervical Junction Guide

A detailed look at Chiari malformation, atlantoaxial instability, and surgical decision-making at the skull-cervical junction.

Download PDF

Lumbar Microdiscectomy Brochure

Everything you need to know about minimally invasive lumbar disc surgery for sciatica — indications, the procedure, recovery, and returning to activity.

Download PDF

Lumbar Stenosis Guide

Understanding the causes and surgical treatment of lumbar spinal stenosis — from anatomy and symptoms to laminectomy and post-operative recovery.

Download PDF

Lumbar Spondylolisthesis Guide

A complete guide to vertebral slippage — understanding grades, causes, symptoms, and the fusion surgery used to correct instability and relieve pain.

Download PDF

Lumbar Revision Fusion Guide

Why lumbar fusion can fail and what corrective surgery involves — covering pseudoarthrosis, flatback deformity, and adjacent segment disease.

Download PDF

Flatback Deformity Guide

Understanding sagittal imbalance and the surgical correction of flatback deformity — causes, consequences, and how osteotomy restores normal posture.

Download PDF

Intradural Spinal Tumors Guide

Classification, diagnosis, and microsurgical treatment of spinal cord tumors — extramedullary and intramedullary — with emphasis on cure rates and neurological recovery.

Download PDF

Your Guide to a Healthy Spine

Practical advice on back pain prevention, proper body mechanics, ergonomics, and exercises to strengthen your spine and avoid surgery.

Download PDF

SpineRecovery
by Dr. Caridi

A personalized recovery companion built specifically for Dr. Caridi's patients. Track your progress day by day, follow your post-operative care plan, log symptoms, and stay connected to your recovery — all from your phone or tablet.

Day-by-Day Recovery Tracker
Follow your personalized post-op timeline with daily milestones and goals.
Symptom & Pain Logging
Track pain levels, symptoms, and activity so you have a complete record for follow-up visits.
Works on Any Device
Open in your phone browser and add to your home screen — no app store required.
Open Recovery App
SpineRecovery
Dr. Caridi · Spinal Associates
Day 14
Post-Operative Recovery
45% complete · 17 days remaining
Today's exercises logged
Pain level: 2/10 ↓
Next follow-up: June 24

Trusted by Patients

Real experiences from patients whose lives have been transformed through expert spine care.

★★★★★

After two failed surgeries elsewhere, I was losing hope. Dr. Caridi not only explained exactly what went wrong, he gave me a clear plan to fix it. Six months after my revision surgery, I'm walking pain-free for the first time in years.

— Former Patient
Revision lumbar fusion
★★★★★

Dr. Caridi took the time to explain my scoliosis diagnosis in a way no other doctor had. His team was with me every step, from pre-op through recovery. The difference in my posture and quality of life is remarkable.

— Former Patient
Adult scoliosis correction
★★★★★

I was terrified of spine surgery, but Dr. Caridi's honesty and calm demeanor put me at ease. He was upfront about what to expect and never oversold the outcome. My neck pain is gone and I'm back to my normal life.

— Former Patient
Cervical disc replacement

Frequently Asked
Questions

Understanding your condition and treatment options is the first step toward recovery.

Surgery is considered when conservative treatments — physical therapy, medications, and injections — have failed after 6–12 weeks, or when there are signs of neurological compromise such as progressive weakness, numbness, or loss of bladder/bowel control. Dr. Caridi always exhausts non-surgical options first.

Success is measured by relief of the symptoms that drove you to surgery — typically arm or leg pain, weakness, or numbness. Imaging studies (X-rays confirming hardware position and fusion) are used to verify technical success. Dr. Caridi follows each patient closely post-operatively to ensure the expected recovery trajectory.

Both perform spinal operations. Neurosurgeons complete additional training in brain and spinal cord surgery. Dr. Caridi is uniquely trained in both — holding fellowships in both neurosurgical spine and orthopedic spine (Hospital for Special Surgery), giving him a broader perspective than surgeons trained in just one discipline.

Absolutely — and Dr. Caridi encourages it. Major spine surgery should never be rushed. Bring all your imaging (MRI, CT, X-rays) and prior operative reports to your consultation. Dr. Caridi provides honest, evidence-based second opinions and will tell you clearly if surgery is or is not indicated in your case.

Recovery varies by procedure. Lumbar microdiscectomy: 4–6 weeks. Single-level ACDF: 4–6 weeks. Multi-level cervical or lumbar fusion: 3–6 months. Complex deformity correction: 6–12 months. Physical therapy begins 4–6 weeks after most procedures and is essential to a full recovery. Dr. Caridi provides a detailed recovery plan before every surgery.

Please bring: all imaging studies on CD or digital format (MRI, CT, X-rays), a list of all prior treatments tried (physical therapy, injections, medications), prior operative reports if you have had previous spine surgery, and a written list of your current symptoms. The more information you bring, the more productive your consultation will be.

Request a Consultation

Dr. Caridi accepts new patients at Spinal Associates in New York City. Please contact the office to schedule your appointment.

Office Address

1155 Park Avenue, Suite E
New York, NY 10128

Phone

(212) 360-6500

Email

info@spinalassociates.com

Schedule an Appointment

We will contact you within one business day to confirm your appointment.

×