Dr. Stephen Koss, MD

Orthopedic Surgery
15 procedures 1 hospital Hackettstown, NJ
Latest available Medicare data — updated April 2026

Contact & Location

Phone: 908-684-3005
Practice phone listed in the NPI registry
108 Bilby Rd
Hackettstown, NJ 07840
NPI: 1265482897
Credentials: MD
Active Medicare provider (NPI verified)
20 years of practice experience
Licensed MD
Licensed surgical specialist
Board-certified orthopedic surgeon
Sports medicine specialist
Contact information available
Find Practice on Google Maps
Shoulder replacement recovery kit Slings, cold therapy, and adaptive clothing for recovery
National Comparison by Procedure
Shoulder 15 vs 29 avg (2,213 surgeons)

Dr. Stephen Koss is a board-certified orthopedic surgeon practicing in Hackettstown, New Jersey. A Medicare provider since 2006, Dr. Koss has performed 15 Medicare-verified shoulder replacements, ranking #31 in New Jersey.

In New Jersey, Dr. Koss performs below average in shoulder (15 vs 29 avg).

Dr. Koss's Medicare data shows a focused shoulder replacement practice with 15 verified procedures. Surgeons who concentrate on a single procedure type often develop deep procedural expertise, though total practice volume may include additional procedures not captured in Medicare fee-for-service data.

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

Dr. Koss's Medicare data spans 12 years, beginning in 2013. Volume peaked at 47 procedures in 2023 before settling at 15 in the most recent data. Changes in Medicare reporting, payer mix shifts, or practice focus adjustments can all influence year-to-year volume.

Dr. Koss's 15 shoulder replacement procedures is below the national average of 29 among 2,213 surgeons. Medicare data captures roughly a third of all joint replacements, so actual volume is likely higher.

Verified Medicare Cases

Shoulder Replacement
15 verified cases
#31 in New Jersey
Estimated total: 40 – 50 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. Koss Compares

Procedure volume compared to the New Jersey state average.

Shoulder Below Avg
15 Avg: 29
Dr. Koss New Jersey Average

Volume Trend Analysis

Dr. Koss's recorded volume peaked at 47 procedures in 2023 and stood at 15 in the most recent data. Year-to-year variation can reflect changes in payer mix, practice scope, or Medicare billing patterns.

Years of Data 12
2024 Volume 15
Peak Volume 47 (2023)
Trend Declining

Hospital Affiliations & Quality

H
Morristown Medical Center
5/5
Morristown, NJ
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.

Patient Resources: Preparing for Shoulder Replacement

If you are considering shoulder replacement surgery, these evidence-based guides can help you prepare and recover:

Shoulder Replacement Recovery Overview

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

Week 1-3 Arm in a sling for protection. Gentle pendulum exercises under therapist guidance. Focus on pain management and wound care.
Week 4-6 Gradual sling weaning. Begin passive and active-assisted range-of-motion exercises. Light daily activities resume.
Week 7-12 Active range-of-motion exercises. Light strengthening begins. Most patients can drive and perform desk work.
Month 4-6 Progressive strengthening continues. Return to most activities. Full recovery may take 6-12 months for complete shoulder strength.

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

Frequently Asked Questions About Dr. Koss

How does Dr. Koss's procedure volume compare to other New Jersey surgeons?

Dr. Koss has performed 15 Medicare-verified joint replacement procedures. The New Jersey average is 72 procedures per surgeon. Medicare data captures roughly one-third of all joint replacements, so total volume may be higher. Dr. Koss ranks #159 out of 184 orthopedic surgeons in New Jersey.

What types of joint replacement does Dr. Koss perform?

Dr. Koss's reported Medicare volume is focused on shoulder replacement, with 15 verified procedures. Some surgeons choose to concentrate on a single joint type to build deep procedural expertise.

Are there other orthopedic surgeons near Dr. Koss in Hackettstown?

Yes. There are 5 orthopedic surgeons in Hackettstown 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 New Jersey surgeons.

What does the Medicare data for Dr. Koss 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. Koss's total practice volume — including private insurance and Medicare Advantage patients — is likely higher than the 15 procedures shown here.

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

Dr. Koss's Medicare-recorded volume peaked at 47 procedures in 2023 and was 15 in the most recent data. Volume fluctuations can reflect changes in payer mix, practice focus, or Medicare reporting rather than a change in overall surgical activity.

Which hospitals is Dr. Koss affiliated with?

According to CMS facility affiliation data, Dr. Koss is affiliated with Morristown Medical Center.

How does Dr. Koss compare to other orthopedic surgeons in Hackettstown?

Among the 5 orthopedic surgeons in Hackettstown, Dr. Koss ranks #4 by total Medicare procedure volume. The highest-volume surgeon in Hackettstown has 324 verified Medicare procedures.

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

Morristown Medical Center (5 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 Hackettstown, New Jersey

Dr. Koss's 15 Medicare procedures are below the Hackettstown average of 77. The table below compares verified procedure volumes for orthopedic surgeons practicing in Hackettstown.

SurgeonProceduresSpecialties
Dr. John Dundon 324 Hip, Knee
Dr. Robert Masella 17 Knee
Dr. Michael Deehan 16 Knee
Dr. Glen Wainen 12 Knee

Patient Resources & Verification

Research reviews, verify credentials, and check official quality data through these trusted sources:

Medicare Care Compare and NPI Registry are official U.S. government sources. Google reviews reflect user-submitted feedback. OrthoProcedures.com does not verify the accuracy of third-party review content.

Cite This Data

APA: OrthoProcedures. (2026). Dr. Stephen Koss, MD -- Orthopedic Surgeon Profile. Retrieved from https://orthoprocedures.com/surgeons/nj/dr-stephen-koss-hackettstown.html

Link: https://orthoprocedures.com/surgeons/nj/dr-stephen-koss-hackettstown.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.