#34 Shoulder
#47 Knee

Dr. Robert Kohen, M.D.

Orthopedic Surgery
64 procedures 3 hospitals Warren, MI
Latest available Medicare data — updated April 2026
Rising Star
Knee replacement recovery kit Ice machines, mobility aids, bathroom safety — under $50 essentials
National Comparison by Procedure
Knee 45 vs 45 avg (6,720 surgeons)
Shoulder 19 vs 28 avg (2,092 surgeons)

Dr. Robert Kohen is a board-certified orthopedic surgeon practicing in Warren, Michigan. A Medicare provider since 2007, Dr. Kohen has performed 45 Medicare-verified knee replacements (#47 in Michigan) and 19 shoulder replacements, for a combined total of 64 procedures.

In Michigan, Dr. Kohen performs above average in knee (45 vs 33 avg), below average in shoulder (19 vs 27 avg).

Dr. Kohen's reported Medicare volume is split between knee replacements (45 cases) and shoulder replacements (19 cases).

Warren is home to 5 orthopedic surgeons in the current Medicare dataset. Patients in the Warren area can compare surgeon volume and procedure specialization to find the right fit for their joint replacement needs.

Medicare records for Dr. Kohen extend back to 2014, covering 10 years of data. Over that period, recorded procedure volume increased from 22 to 64 in the most recent data, a 191% increase. This sustained growth reflects an expanding joint replacement practice.

Among 6,720 knee replacement surgeons tracked nationally, Dr. Kohen's 45 verified procedures is near the national average of 45.

Verified Medicare Cases

Knee Replacement
45 verified cases
#47 in Michigan
Shoulder Replacement
19 verified cases
#34 in Michigan
Estimated total: 170 – 190 procedures (all insurers)
Based on Medicare FFS representing 33–37% of national joint replacement volume
How is this estimated?

Medicare Part B fee-for-service claims represent approximately 33–37% of all joint replacements performed nationally (source: CMS data, AJRR). This range estimates the surgeon's total practice volume across all payers. The verified Medicare count above is the definitive, audited figure.

How Dr. Kohen Compares

Procedure volume compared to the Michigan state average.

Knee High
45 Avg: 33
Shoulder Below Avg
19 Avg: 27
Dr. Kohen Michigan Average

Contact & Location

Phone: 586-558-2870
28800 Ryan Rd
Warren, MI 48092
NPI: 1780809574
Credentials: M.D.
Active Medicare provider (NPI verified)
19 years of practice experience
Licensed M.D.
Licensed surgical specialist
Board-certified orthopedic surgeon
Sports medicine specialist
Contact information available
Find Practice on Google Maps

Volume Trend Analysis

Dr. Kohen's Medicare-recorded procedure volume has trended upward over 10 years, increasing 191% from 22 procedures in 2014 to 64 in the most recent data.

Years of Data 10
2023 Volume 64
Peak Volume 71 (2018)
Trend Growing

Hospital Affiliations & Quality

H
Trinity Health Oakland Hospital
★★☆☆☆
Pontiac, MI
Similar to national avg
H
Corewell Health William Beaumont University Hospit
★★★☆☆
Royal Oak, MI
Similar to national avg
H
Corewell Health Farmington Hills Hospital
★★☆☆☆
Farmington Hills, MI
Similar to national avg

Quality ratings and complication rates are hospital-level metrics from CMS Hospital Compare and do not reflect individual surgeon performance. Star ratings updated quarterly. Complication data covers a rolling 3-year period.

Knee Replacement Recovery Overview

Recovery timelines vary by patient, but here is a general overview of what to expect after knee replacement surgery:

Week 1-2 Walking with assistive device. Knee bending exercises begin immediately. Ice therapy and elevation for swelling control.
Week 3-6 Increased range of motion (target 90 degrees). Walking longer distances. Physical therapy intensifies with strengthening exercises.
Week 7-12 Most patients walk without assistive devices. Resume driving and desk work. Continue PT for strength and flexibility.
Month 4-6 Near-full recovery. Resume most recreational activities. Some swelling and stiffness may persist but continues improving.

Individual recovery varies based on overall health, age, and adherence to physical therapy. View full knee replacement recovery guide and product recommendations

Frequently Asked Questions About Dr. Kohen

How does Dr. Kohen's procedure volume compare to other Michigan surgeons?

Dr. Kohen has performed 64 Medicare-verified joint replacement procedures. This is in line with the Michigan average of 48 procedures per surgeon. Dr. Kohen ranks #64 out of 272 orthopedic surgeons in Michigan.

What types of joint replacement does Dr. Kohen perform?

Dr. Kohen's Medicare data shows procedures in knee replacement (45 cases) and shoulder replacement (19 cases).

Are there other orthopedic surgeons near Dr. Kohen in Warren?

Yes. There are 5 orthopedic surgeons in Warren in the current Medicare dataset. Patients can compare procedure volumes and specializations to choose the surgeon who best fits their needs. Use the state page to view all Michigan surgeons.

What does the Medicare data for Dr. Kohen represent?

The procedure counts shown are based on the most recent Medicare Part B fee-for-service claims data, published by the Centers for Medicare and Medicaid Services (CMS). This captures approximately 33–37% of all joint replacements performed nationally. Dr. Kohen's total practice volume — including private insurance and Medicare Advantage patients — is likely higher than the 64 procedures shown here.

Has Dr. Kohen's procedure volume changed over time?

Yes. Dr. Kohen's Medicare-recorded volume has increased from 22 procedures in 2014 to 64 in the most recent data, a 191% increase over 10 years. This upward trend suggests an expanding joint replacement practice. Peak volume was 71 procedures in 2018.

Does Dr. Kohen perform more than one type of joint replacement?

Yes. Dr. Kohen's Medicare data shows procedures in knee replacement (45 cases), shoulder replacement (19 cases). Surgeons who perform multiple joint replacement types maintain broad technical skills across different anatomical joints.

Which hospitals is Dr. Kohen affiliated with?

According to CMS facility affiliation data, Dr. Kohen is affiliated with Trinity Health Oakland Hospital, Corewell Health William Beaumont University Hospit, Corewell Health Farmington Hills Hospital.

How does Dr. Kohen compare to other orthopedic surgeons in Warren?

Among the 5 orthopedic surgeons in Warren, Dr. Kohen ranks #1 by total Medicare procedure volume. Dr. Kohen has the highest verified Medicare volume in the city.

What are the quality ratings for hospitals where Dr. Kohen practices?

Trinity Health Oakland Hospital (2 out of 5 CMS stars, hip/knee complication rate similar to national average); Corewell Health William Beaumont University Hospit (3 out of 5 CMS stars, hip/knee complication rate similar to national average); Corewell Health Farmington Hills Hospital (2 out of 5 CMS stars, hip/knee complication rate similar to national average). These are hospital-level quality metrics from CMS Hospital Compare and do not reflect individual surgeon outcomes.

Other Orthopedic Surgeons in Warren, Michigan

Dr. Kohen's 64 Medicare procedures are above the Warren average of 38. The table below compares verified procedure volumes for orthopedic surgeons practicing in Warren.

SurgeonProceduresSpecialties
Dr. Jeffrey Mendelson 47 Hip, Knee
Dr. David Mendelson 45 Hip, Knee
Dr. Steven Plomaritis 21 Knee
Dr. Ronald Rook 12 Knee

Patient Reviews & Ratings

OrthoProcedures.com focuses on verified Medicare procedure data. For patient reviews, ratings, and appointment scheduling, visit these trusted platforms:

These links lead to third-party websites. OrthoProcedures.com is not affiliated with these platforms and cannot verify the accuracy of reviews.

Cite This Data

APA: OrthoProcedures. (2026). Dr. Robert Kohen, M.D. -- Orthopedic Surgeon Profile. Retrieved from https://orthoprocedures.com/surgeons/mi/dr-robert-kohen-warren.html

Link: https://orthoprocedures.com/surgeons/mi/dr-robert-kohen-warren.html

Data source: CMS Medicare Part B Provider Utilization & Payment Data. Full methodology | Open Data API

Important: Rankings are based solely on Medicare procedure volume and do not reflect quality of care, patient outcomes, or procedures covered by private insurance. This data represents approximately one-third to 40% of all joint replacement procedures nationwide. Always consult with healthcare providers to make informed decisions about your care.