Flexion-Distraction Tables: A Cox-Trained Buyer's Guide to Hill AFT, Lloyd 402, and Zenith 230

If you’ve never seen flexion-distraction technique (F/D) before, here’s the thirty-second version: the patient lies face-down on a specialized table, and the chiropractor uses the table’s moving lower section — called the caudal section or “tail piece” — to gently apply traction and rhythmic flexion to the lumbar spine (lower back) while simultaneously contacting the vertebrae by hand. The goal is to decompress intervertebral discs (the gel-like cushions between vertebrae) and open the facet joints (small sliding joints at the rear of each spinal segment). The technique was codified by Dr. James Cox and has a stronger clinical evidence base than most manual techniques, with research into its mechanisms documented across chiropractic college and peer-reviewed literature (Cox JM, Low Back Pain: Mechanism, Diagnosis and Treatment, 7th ed., Wolters Kluwer, 2011). The table is not incidental to the outcome — it is the technique. If you’re a Cox-trained DC deciding between the Hill AFT, the Lloyd 402, and the Zenith 230, this guide is for the version of you who already knows the protocol cold and wants the second-order purchasing arguments.

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The Three Tables, Unromantically Summarized

Hill Laboratories Auto Flexion Table (AFT): The motorized option. A built-in drive mechanism cycles the caudal section through a programmable flexion arc automatically, which is why it’s called an auto-flexion table. Street price in 2026 sits in the $7,200–$8,400 range depending on upholstery spec and dealer. Hill has manufactured F/D tables in Frazer, Pennsylvania since the 1950s and the AFT is their flagship.

Lloyd Table Company Model 402: Manual operation, meaning you drive the caudal section with your body weight and hand contact — which is actually how Cox certified technique is taught. The 402 has been the institutional workhorse at many Cox certification courses and chiropractic college F/D labs for decades. Current dealer pricing runs $3,800–$4,600.

Zenith 230 (Williams Healthcare): Also manual, with a longer caudal section than the Lloyd and a wider lateral flexion range. Pricing tracks closely with the Lloyd: $4,000–$4,800 depending on configuration. Zenith is owned by Williams Healthcare International, which also makes the Thompson drop-piece tables most DCs trained on.

By the Numbers

	Hill AFT	Lloyd 402	Zenith 230
Drive	Motorized (auto-cycle)	Manual	Manual
Caudal section length	~28 in	~24 in	~30 in
Lateral flexion	±15°	±12°	±18°
Documented distraction force gauge	No	Yes (optional)	No
2026 street price (mid-spec)	~$7,800	~$4,200	~$4,400
Approximate weight capacity	350 lb	300 lb	300 lb

Sources: manufacturer published specs; dealer quotes current as of Q1 2026. Verify with authorized dealer before purchase.

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The Auto-Flexion Question Is Not as Simple as It Looks

The Hill AFT’s primary selling point — the motorized cycle — deserves real scrutiny rather than reflexive enthusiasm or reflexive dismissal.

The case for motorized: In a busy lumbar practice running 20–30 F/D cases per day, manual distraction accumulates meaningful ergonomic load on the practitioner’s wrists, shoulders, and lower back. This is not a trivial concern. The OSHA Technical Manual, Section VII: Ergonomics (OSHA Publication 3125) identifies repetitive manual exertion as a primary risk factor for work-related musculoskeletal disorders, including cumulative loading on the upper extremities and spine. If the Hill AFT buys you another decade of practice longevity by reducing that daily mechanical burden, it may well be the cheaper table over a 15-year horizon.

The Hill also allows the practitioner to focus entirely on contact hand placement and patient response during the cycle, rather than simultaneously managing the mechanical effort of driving the caudal section. For instructors, it standardizes the arc for teaching purposes.

The case against (or at least: the caveat): Cox technique in its certified form is a coupled maneuver — the caudal section movement and the contact hand input are supposed to be coordinated in real time, responsive to tissue feedback. The AFT runs a preset cycle. The technique purists argue, with some justification, that you’re not really doing Cox if the table is driving rather than you. That’s an argument about clinical fidelity, not just marketing.

The more practical concern: the AFT’s motor introduces a maintenance variable that the manual tables don’t have. Hill’s service network is solid — they’ve been at this long enough — but a motor failure means a table out of service, a service call, and parts lead time. For a solo practice without a backup table, that’s a real operational risk. Get the extended warranty in writing, understand the service SLA (service level agreement — the guaranteed response time), and confirm parts availability before signing.

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Why the Lloyd 402’s Force Gauge Actually Matters Clinically

The Lloyd 402 offers an optional distraction force gauge — a dial indicator that tells you, in real time, how many pounds of distraction force you’re applying to the caudal section. This sounds like a niche feature. It is not.

Documentation: In an increasingly audit-conscious billing environment, the ability to chart “applied X lbs distraction force, Y repetitions, Z segments” transforms a narrative note into a measurable clinical record. The American Chiropractic Association has consistently emphasized evidence-informed clinical documentation as part of professional standards for chiropractic practice; force quantification is one concrete way to operationalize that standard at the treatment unit level.

Reproducibility: Cox’s own protocol specifies distraction distances and force ranges for different disc pathologies and patient presentations (Cox JM, Low Back Pain: Mechanism, Diagnosis and Treatment, 7th ed., Wolters Kluwer, 2011). Without a gauge, you’re estimating. With one, you’re calibrating. For post-surgical cases, severe disc herniations, or osteoporotic patients where distraction force should be deliberately minimal, the gauge gives you a safety ceiling you can actually enforce and document.

The Zenith 230 and Hill AFT do not offer a comparable real-time force measurement. Hill publishes motor torque specs but that’s not the same thing as measurable patient-applied distraction. If your practice has a meaningful medico-legal exposure — think personal injury, workers’ comp, post-surgical — this Lloyd feature alone may be worth the conversation.

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The Zenith 230’s Lateral Flexion Range and Who Actually Needs It

The Zenith 230’s ±18° lateral flexion is the widest in this comparison. Lateral flexion (side-bending the caudal section) is used to open the lateral recess — the channel through which the nerve root exits — and to address lateral disc herniation presentations and scoliotic (curved spine) cases.

If your practice skews toward lumbar radiculopathy (nerve pain running down the leg, commonly from a disc pressing on a nerve root) with a lateral component, or if you’re managing adolescent scoliosis cases with F/D as an adjunct, the Zenith’s extra lateral range is genuinely functional, not just a spec on a brochure.

For a generalist lumbar practice, the Lloyd’s ±12° is adequate for the majority of presentations. The Zenith’s longer caudal section (approximately 30 inches versus the Lloyd’s 24) is useful for taller patients and allows more distal foot-end leverage, which changes the mechanical advantage of the distraction stroke.

One compatibility note: the Zenith 230 uses Williams Healthcare’s own ankle strap system. These are not interchangeable with Lloyd’s ankle strap hardware. If you’re buying aftermarket or replacement straps, confirm fitment before ordering. This is exactly the kind of $250 accessory gotcha that turns a simple reorder into a return.

For practitioners wanting to explore complementary positioning accessories, bolster systems are sometimes used for patient positioning pre-treatment on a secondary table — not a replacement for the F/D table itself, but a useful adjunct in a multi-modality room. Similarly, practitioners running mobile consultations or satellite offices sometimes keep a portable massage table on hand for initial assessments before transitioning patients to the primary F/D unit. For basic cervical distraction adjuncts, over-door cervical traction devices are occasionally prescribed as home-care companions to in-office F/D work — worth knowing if you’re building a home-care protocol around the technique.

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Total Cost of Ownership: Running the Actual Math

The Hill AFT’s $7,800 mid-spec price tags it as the premium option. Before that number sends you to the Lloyd, run the Section 179 math.

Section 179 of the U.S. tax code allows businesses to deduct the full purchase price of qualifying equipment in the year of purchase rather than depreciating it over years. For a solo DC in a 35% effective tax bracket purchasing an $8,000 Hill AFT in 2026, the federal deduction alone reduces net cost by roughly $2,800 — bringing effective cost to approximately $5,200. State Section 179 provisions vary but often provide additional relief. Chiropractic Economics has covered this framework in detail; your accountant should be running these numbers before any capital equipment purchase above $3,000.

Financing at current 2026 equipment lending rates (roughly 7.5–9.5% for well-qualified buyers via chiropractic-specific lenders) over 60 months puts the Hill AFT at approximately $155–$165/month pre-tax. The Lloyd 402 at $4,200 runs approximately $83–$90/month. The after-tax delta between the two is narrower than the sticker prices suggest.

Upholstery refresh is where buyers systematically underestimate long-term cost. F/D table upholstery takes more cumulative stress than a standard adjusting table because of the flexion and distraction forces transmitted through the surface. Budget for a professional reupholster every 5–7 years in a busy practice: $400–$700 depending on material grade. Both Lloyd and Zenith use standard-diameter foam and vinyl that most chiropractic upholstery shops can source. Hill uses a proprietary cushion profile on the AFT’s caudal section — confirm parts availability with Hill directly before year 10.

Used and refurbished market note: Lloyd 402s appear on the used market with reasonable frequency — they’re built to last and clinics that close or upgrade often liquidate them through dealer networks or direct sale. A well-maintained Lloyd 402 from a closed practice, serviced and reupholstered, can be had for $1,800–$2,500. The Hill AFT used market is thinner and motor condition is harder to assess remotely; budget for a pre-purchase inspection or buy through a dealer who will certify motor hours. Zenith 230s are available used but parts sourcing through Williams Healthcare’s authorized service network should be confirmed before committing.

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The Honest Bottom Line

For a new graduate building a Cox-focused practice on a constrained budget: the Lloyd 402 with the force gauge option is the defensible choice. It’s what you trained on, it ships with predictable parts availability, and the force documentation feature has real clinical and medico-legal value that its competitors don’t match.

For an established practitioner with a high-volume lumbar caseload and ergonomic concerns about practice longevity: the Hill AFT is worth the premium once you’ve run the Section 179 math and confirmed the service SLA with your Hill dealer.

For practices with a significant lateral disc herniation or scoliosis caseload, or practitioners working with tall or larger patients where caudal section length limits technique execution: the Zenith 230 deserves a serious look that most buyers skip because the brand is less prominent in F/D-specific circles.

None of these are bad tables. The arguments between experienced Cox practitioners about which one is “correct” are mostly arguments about clinical philosophy and workflow preference — which is appropriate, because at this price tier, you’re not choosing between adequate and inadequate. You’re choosing between different expressions of the same technique, optimized for different practice realities. Know your practice before you know your table.

Disclosure: This article contains affiliate links to Amazon product pages. chiropractortable.com may earn a commission on qualifying purchases at no additional cost to you. Manufacturer table pricing is sourced from dealer quotes and is subject to change; verify current pricing with authorized dealers before purchase.