Supply Planning for Dural Grafts: Sizes, Turns and Order Quantities

Dural graft supply planning starts with demand by size, not by product. Each account uses a few sizes often and others rarely, and spine use is largely unplanned. A distributor plans well by classifying sizes by movement, holding buffer centrally rather than everywhere, matching order quantities to lead times and sharing a rolling forecast with the manufacturer.

This article is for distributors carrying a collagen dural graft line such as DESU’s DURASHEET and DECOLL, each supplied in four sizes. It looks at the warehouse and purchasing side of the business rather than the hospital shelf.

Why is dural graft planning different?

Dural grafts combine several features that make planning harder than for typical consumables. Unit volumes are modest, so random variation is large relative to average demand. Demand is spread across sizes. Some use is scheduled, as in planned cranial duraplasty, and some is sudden, as after an incidental durotomy. And the product has an expiry date, so overstock eventually becomes write-off.

When the manufacturer is overseas, lead times add another layer. A distributor cannot rely on next-day replenishment from the factory, so its own stock must cover demand during the replenishment cycle with an allowance for surprises.

None of this is unusual for implant distribution, but it rewards a deliberate approach. Planning by instinct tends to produce both stockouts of the critical size and expired units of the others.

The cost of each mistake is different. A stockout can mean a surgeon opening a different graft, or a rep driving across the territory with a single unit, and it damages trust that took months to build. Expired stock is a direct financial loss. Good planning keeps both risks visible and accepts a small amount of each rather than removing one at any cost.

How do you build the demand picture?

Start at the account level and build upwards. For each account, estimate monthly use by product and size from purchase history, evaluation data or, for new accounts, the procedure map agreed with the surgeons.

• Separate scheduled cranial demand, which can be anticipated from the OR schedule, from contingency spine demand, which cannot.
• Record which sizes each surgeon actually uses, not only what was ordered.
• Flag accounts in ramp-up, where demand will grow as more surgeons adopt the product.
• Note seasonal or structural changes, such as a surgeon leaving or a new spine center opening.

Adding these estimates gives a territory forecast by size. It will be wrong in detail, as every forecast is, but it provides a baseline that can be corrected each month as real orders arrive.

Where possible, capture actual use rather than orders. Hospitals order in batches, and a large order may simply refill a consignment cabinet. Usage reports from consignment programs, bill-only records and rep notes from cases give a truer picture of demand than purchase orders alone, especially in the first year of a new line.

How should sizes be classified?

Not all sizes deserve the same stocking policy. A simple classification by movement helps:

The classification differs by territory. A territory dominated by spine accounts may move the smaller sizes fastest; one with busy cranial tumor and trauma services may see more demand for larger sizes. Review the classes every quarter rather than setting them once.

What inventory turns are realistic?

Inventory turns, the ratio of annual usage to average inventory, measure how hard stock is working. Higher turns mean less cash tied up and less expiry risk. But a dural graft is a product whose absence in a case is costly, so turns cannot be pushed up indefinitely by cutting stock.

The usual compromise is to keep turns high in the distributor’s central warehouse, where stock serves many accounts, and accept lower turns on the small contingency stocks placed in spine rooms and ambulatory centers. Pooling buffer stock centrally rather than spreading it across every account is the single most effective way to improve overall turns without hurting service.

Track turns by size class. If slow movers show very low turns, the answer is usually to stop placing them in accounts that rarely need them and to rely on fast delivery from central stock instead.

Explain this to accounts openly. Most OR managers accept that a rarely used size is held centrally if the distributor can show how quickly it will arrive when needed, and many prefer it to holding stock that may expire on their own shelves.

How do order quantities and lead times fit together?

Order quantities and minimum order quantities should be discussed with the manufacturer, because they depend on production planning, packaging and shipping. Once known, they shape the distributor’s order cycle. A practical method for each size is the classic reorder point: expected demand during the replenishment lead time, plus safety stock to cover variation and delays.

Consolidating orders helps. Combining dural graft sizes with other lines from the same manufacturer, such as external drainage systems or catheter kits, can make shipments more efficient. Agreeing shipping terms clearly, for example using Incoterms, avoids confusion about who arranges and pays for each stage of transport.

Build in a margin for customs processing and domestic transport, and for public holidays at both ends of the route. Planning around a shipment that arrives a week later than expected is far easier than explaining a stockout to an OR manager.

How should expiry be managed?

• Check remaining shelf life on receipt and record expiry dates by lot in the warehouse system.
• Ship first-expiry-first-out, so older lots leave first.
• Rotate slow-moving units out of accounts and back to central stock, or to busier accounts, well before expiry.
• Set alerts for lots approaching expiry, with enough time to act.
• Review write-offs by size each quarter and adjust stocking policy accordingly.

Expiry management is where good planning pays for itself. A distributor that rarely writes off grafts can afford better service and keeps its margin. It also avoids an awkward conversation with accounts that discover short-dated units on their shelves.

Agree with each account how close to expiry a unit may be when it is delivered. Hospitals often have their own rules on this, and knowing them in advance prevents rejected deliveries.

How should the plan be shared with the manufacturer?

A rolling forecast, updated monthly and covering several months ahead, lets the manufacturer plan production and shipments. It should highlight changes: new accounts, evaluations, surgeons joining or leaving and any expected step change in demand. Manufacturers plan better with an honest forecast that changes than with an optimistic one that never does.

Because DESU designs and manufactures its products in its own cleanrooms, forecasts shared by distributors go directly to the people who plan production. Sharing changes early makes that planning easier for both sides.

Talk to a DESU product specialist

If you are planning stock for DURASHEET and DECOLL, DESU’s product specialists can discuss order quantities, lead times and shipping options for your market. Write to sales@desu.tr, use the contact page, or request a quote with your first forecast.