Knees are the workhorse injury of physical jobs — and the body part where the gap between “the diagnosis” and “the number” confuses people most. A meniscus tear isn’t worth anything by itself; the whole-person impairment the physician assigns is, after the schedule adjusts it for your job and age. This page computes that, across the whole realistic range, with every figure from the rating engine.
How knee injuries are measured
The AMA Guides rate knees (impairment number 17.05.04.00 for range of motion; diagnosis-based alternatives exist) from examination findings and surgical outcomes. As rough anchors: a partial meniscectomy with a good result commonly lands in the low single digits of WPI; ligament laxity and cartilage damage run higher; and arthroplasty — a knee replacement — reaches the mid-teens to high-20s depending on the result. The WPI is the physician’s call; everything after it is arithmetic.
The money table
Final PD and total indemnity, computed for three occupations at age 42–46, 2026 injury, maximum PD rate ($290/week), single impairment, before apportionment:
| WPI | Clerical · 111 | Custodian · 340 | Carpenter · 380 |
|---|---|---|---|
| 4% | 5% · $4,350 | 8% · $6,960 | 10% · $8,772.50 |
| 8% | 10% · $8,772.50 | 14% · $13,412.50 | 17% · $17,545 |
| 12% | 15% · $14,645 | 20% · $21,895 | 24% · $27,695 |
| 16% | 19% · $20,445 | 25% · $29,217.50 | 31% · $40,020 |
| 20% | 25% · $29,217.50 | 33% · $44,080 | 38% · $54,230 |
| 25% | 32% · $42,050 | 40% · $58,290 | 46% · $70,470 |
The knee’s occupational variants run steep: jobs built on standing, climbing, and carrying (group 380) rate the same WPI several brackets above desk work — the schedule prices lost earning capacity, not anatomy. Every percentage maps to weeks and dollars on the PD money chart.
Same WPI, different jobs — the strings
The variant letter (D vs. I) is the whole difference — $13,050 of it. Paste either string into the rating-string decoder to see every step verified against the schedule.
Apportionment: the arthritis discount
Degenerative changes in the knee are the classic §4663 non-industrial factor — imaging past 40 almost always shows some. The physician’s split applies at the end:
Unapportioned, the same knee rated 31% PD — $40,020. One sentence in the report removed $10,802.50. Whether that split is substantial evidence is where knee cases are fought; see how apportionment works.
What this table can’t tell you
A knee rarely travels alone — an altered gait pulls in the hip and back, and multiple parts combine on the CVC rather than add. Below-maximum wages scale the dollars down, and settlements price future medical (a future revision surgery is real money) beyond any table. Companion pages: the back and shoulder versions of this analysis. Estimates for informational use; not legal or medical advice.