Table 1.
Total knee arthroplasty surgical backlog after a 3-month deferment order.
| Months | #Patients | Surgical capacity | #TKR performed | #TKR delayed | 0–30 d | 30–60 d | 60–90 d | 90+ d | TKR backlog |
|---|---|---|---|---|---|---|---|---|---|
| 20-March | 75,000 | 0% | — | 75,000 | 75,000 | — | — | — | 75,000 |
| 20-April | 75,000 | 0% | — | 75,000 | 75,000 | 75,000 | — | — | 150,000 |
| 20-May | 75,000 | 0% | — | 75,000 | 75,000 | 75,000 | 75,000 | — | 225,000 |
| 20-June | 75,000 | 25% | 18,750 | 56,250 | 75,000 | 75,000 | 75,000 | 56,250 | 281,250 |
| 20-July | 75,000 | 50% | 37,500 | 37,500 | 75,000 | 75,000 | 75,000 | 93,750 | 318,750 |
| 20-August | 75,000 | 75% | 56,250 | 18,750 | 75,000 | 75,000 | 75,000 | 112,500 | 337,500 |
| 20-September | 75,000 | 100% | 75,000 | — | 75,000 | 75,000 | 75,000 | 112,500 | 337,500 |
| 20-October | 75,000 | 110% | 82,500 | −7,500 | 75,000 | 75,000 | 75,000 | 105,000 | 330,000 |
| 20-November | 75,000 | 110% | 82,500 | −7,500 | 75,000 | 75,000 | 75,000 | 97,500 | 322,500 |
| 20-December | 75,000 | 125% | 93,750 | −18,750 | 75,000 | 75,000 | 75,000 | 78,750 | 303,750 |
Model based on the estimation of 966,000 knee arthroplasties per year.23 The model assumes (a) an even distribution of 75,000 procedures per month, (b) that the orthopedic surgical system full capacity equals 75,000 cases per month, (c) a progressive return to full capacity over 3 months (June-20 to September-20), (d) the procedures are rescheduled in chronological order to the initial presentation, (e) that other non-TKA surgeries do not affect the recovering surgical capacity, and (f) the ability to implement surgical overcapacity by the end of the year (increasing an excess of 25% of procedures). The bold numbers represent the total TKR surgeries delayed at the end of each period (#TKR delayed) as well as the size of the surgical backlog (TKR Backlog) that includes patients waiting for 1 month, 1 to 2 months, 2 to 3 months and more than 3 months. The Italic text represents the backlog inflection point (highest backlog reached on August) and the final size of the backlog at the end of 2020 (20‐Dec).