Risk and Cost Analysis Regarding Plant Box Safety

Risk and Cost Analysis Regarding Plant Box Safety

By Jan Johnson

Thanks to the following for your timely help and support with this project:

Jason Shimko - Get Vertical PV Club, Milwaukee, Wisconsin, Peter Mcginnis, Ph.D. - SUNY Cortland, Eddie Seese - Former Chair ASTM PV Sub Committee, David Spease -NPSI certified Play Ground Inspector, Will Freeman - Head Track Coach Grinnell College, Kevin Ferguson –PV Coach Henderson Ky. HS, Dr Russ VerSteeg - New England School of Law, Sky Jumpers Connecticut PV Club, David Nielson Idaho State University, Mike Yurcho – Cal Track and Engineering. Dr Barry Boden, The Orthopedic Center, Rockville, Maryland, andDavid Hodge - Gill Athletics

Contents:

P1Introduction- Head Injury Criteria of Padded and Unpadded Box Surface Comparisons

P2 Mechanism and Result Serious and Catastrophic Injuries

P2 Landing Pad Schematic

P Head Injury Risk Probability Curves

P5-8Catastrophic Injuries in Pole-Vaulters: A Prospective 10-Year Follow-up Study

P9-10 Box Padding Photos

P11-12 Prototype Photos

Introduction:

Although major injuries in falls off the side of landing pads, and off the rear are now far less common than in the past. Box landings resulting in Major injuries are still very common. The purpose of this project is to better protect the pole vault plant box area and thus improve the safety of Pole Vault Participants in the future. Unfortunately over the past ten years we have had a large number of plant box landings result in serious injury.

This document shows how much protection can be increased and what the expected costs and benefits will be. Several methods and combination of methods are currently available for this purpose.

Below: This college facility has approximately 1728 sq inches of poorly or unprotected surfaces. I have labeled the approximate HIC values from our testing for each location. Keep in mind that in the probability chart at the bottom of this document tells us that fatal head injuries begin at approximately 1000 HIC, 3000 Hic is almost always fatal. See Chart at the end of this document to better understand HIC and its relationship to head injuries. .

Below: with box collar and Soft Pan only 112 sq inches of unpadded surfaces remain. 94 % are padded well beyond the 1000 HIC threshold where research shows serious injuries begin. (See HIC probability chart below for more information.)Many ways exist to improve the protection in this area. Total costs to retrofit the plant box as show below is less than $1000. More expensive methods also exist.

Estimated Methods Costs and Benefits:

Box Collar with Interior Side Wall Padding: $500 parts, Labor $0 Install works with any plant box to increase protection, can be carried from facility to facility. (pads 65% of currently unprotected surfaces, works in any box, when combined with GreyBack or SoftBox padding will exceed ASTM specification by 50%) Available immediately, could be the first of two part upgrade over the next couple of years.

GreyBack Box:. Not yet on the market. Projected cost $1400 parts, labor $500 works best with collar as show above, still leaves a hard rim, put softens inner side walls more, fits into the same sized hole as the old box.Pads 98% of unprotected surfaces.

New SoftPan Box: $1400 parts plus labor $500, (pads bottom pan or 30% of unpadded surfaces could be second of two part upgrade, fits directly into the same sized hole the old style box come out of)

New Box:$2500 parts plus Labor $2000, (Pads 100% of all hard surfaces, can’t work in many facilities,may have deformation problems)

Retrofit existing Plant Box #1 Method: Parts $150 Labor $200,Replaces bottom of box with desired padding and plastic in a simple way. Any program with a maintenance dept can install in 2 or 3 hours.

Retrofit existing Plant Box #2 Method: Parts $200, Labor $200, Replaces bottom of box with desired padding in a simple way. Any program with a school maintenance dept can install in 2 or 3 hours.

Polyurethane Box: Parts (estimated) $500, Labor (estimated) $1000, currently is in the early phase of testing but showing some promise. Force impact capabilities unknown.

Foam Core Box: Costs unknown, currently in design phase, holds great promise, Force impact capabilities showing great potential.

Pole Vault Helmets: $60 each, not very protective, approximately 4x less protective than our proposed ASTM specification for box padding. 10x less protective than pole slide testing. Long term costs look high when you consider number of participants per school and replacements each year.

*** Note that we have instructional videos available for all installs and retrofits.

Mechanism and Result of Serious and Catastrophic Plant Box Landings

Box Area Accidents Only 1971-2011
Mechanism
Hand slip off pole and head hit in box / 8
Stall and land short in the box / 25
Total / 33
Skull Fractures / 22
Temporary paralysis / 1
Permanent paralysis / 3
Fractured vertebrae / 7
Severed Brain Stem / 3
Broken or separated shoulder / 4
Fractured Tailbone / 4
Punctured lung / 5
Broken Ribs / 5
Broken hip / 2
Broken Pelvis / 1
Death / 7
Box Area Accidents 2003-2011
Mechanism
Hand slip off pole and head hit in box / 5
Stall and land short in the box / 9
Total / 14
Skull Fractures / 5
Temporary paralysis / 1
Permanent paralysis / 1
Fractured vertebrae / 5
Severed Brain Stem / 0
Broken or separated shoulder / 2
Fractured Tailbone / 3
Punctured lung / 3
Broken Ribs / 3
Broken hip / 1
Broken pelvis / 1
Death / 1

Fall Locations Resulting in Serious or Catastrophic Injuries 2003-11

Catastrophic Injuries in Pole-Vaulters: A Prospective 10-Year Follow-up Study

(Digested Version of Findings)

Barry P. Boden, MD*, Matthew G. Boden*, Rebecca G. Peter, Peter M. McGinnis**, Fred O. Mueller, PhD***, and Jan Johnson MS. ****

From *The Orthopaedic Center, Rockville, Maryland, **State University of New York Cortland, New York, the ***Department of Physical Education, Exercise and Sport Science, the University of North Carolina at Chapel Hill, North Carolina, and the ****National Pole Vault Safety Committee, Atascadero, California

Counts: words (max 6000), references (max 60)

§Address all correspondence and reprint requests to: Barry P. Boden, MD, The Orthopaedic Center 9420 Key West Ave. #300 Rockville, MD 20850 (301-424-1287; fax 301-424-5266; ).

Risk Comparisons

Pole vaulting ranks as one of the most dangerous activities according to the NCCSIR (Thomas, Mueller). In one report that analyzed the US National Registry of Sudden Death in Young Athletes for a 30-year period from 1980 to 2009, pole vaulting had the second highest number of direct, traumatic fatalities after football (Thomas). For the 28-year period from the fall of 1982 through the spring of 2010 the NCCSIR reported 1284 direct catastrophic injuries in high school and college sports (NCCSIR, 28th report). During the same time period the direct catastrophic injury rate per 100,000 athletes for all sports combined was 0.62 and 2.54 for high school and college respectively (28th report). After the 2003 rule changes the direct catastrophic rate of 0.7 (1.1 in males and 0.28 in females) per 100,000 high school pole vaulters is comparable to the overall catastrophic incidence for all high school sports. However, the rate of direct catastrophic injuries in college pole vaulters after the 2003 rule changes (28.4 overall, 42.3 for males and 11.8 for females) was significantly higher than the combined rate of 2.54 for all college sports and indicates that more emphasis needs to be placed on preventing pole vaulting injuries at the college level. For male college athletes, pole vaulting (42.3) has the highest rate of catastrophic injuries per 100,000 participants, followed by gymnastics (25.05), ice hockey (10.22), football (9.5) and lacrosse (5.28) (NCCSIR, 28th report). For female college athletes, skiing (12.46) has the highest rate of catastrophic injuries per 100,000 participants, followed by pole vaulting (11.8), equestrianism (10.85), gymnastics (4.8) and ice hockey (4.71) (NCCSIR, 28th).

Accidents off the Side and Off the Rear

All four of the athletes that missed the sides or rear of the landing pads after the 2003 rule changes were participating at the college level and landed on hard surfaces, FieldTurf in two cases, concrete with a thin layer of rubber in one case, and a rubberized gym floor in one case. Two of these cases were in noncompliance with the 2003 rule changes by using a landing pad that didn’t meet the minimum size requirements or substituting multiple high jump pads for a pole vault landing pad. In 2003 the NFHS also mandated that all hard surfaces surrounding the sides and back of the landing pad should be eliminated or covered with a minimum of 2 inch thick unspecified soft padding (ref). The NCAA has no similar rule. If the NCAA mandated a similar rule requiring soft surrounding surfaces and all schools were in compliance there may have been no catastrophic injuries from athletes missing the sides or back of the landing pad after 2003. None of the catastrophic injuries in the current or prior study occurred due to an athlete landing on a surrounding surface of grass, dirt, sand, wood chips, or 2” of padding ( ). We recommend strict adherence to the minimum landing pad dimensions and that the type of padding on the surfaces that surround the sides and back of landing pad be specified and at least two inches of padding be used.

Vault Box injuries

While the number of catastrophic injuries from athletes missing the sides and back of the landing pads decreased compared to the prior study, the number of injuries due to athletes landing in the vault box more than tripled from 0.5 per year in the earlier study (ref) to 1.7 per year in the new study (1.55 after the 2003 rule changes) and is cause for concern. The vault box survey also indicated that a large percentage of pole vaulters landed in the vault box during their career. In fact 84% of those surveyed landed in the vault box at least once and 7% landed in the vault box at least four times. Most of these pole vaulters were relatively inexperienced, amateur pole vaulters with an average personal best of ten feet and two years of vaulting experience. It is difficult to determine if these numbers plateau, increase, or decrease with more years of vaulting. The number of vaults would likely increase the chances of landing in the vault box, but the additional experience may reduce the incidence of box landings. It is likely that elite pole vaulters land less frequently in the vault box, but have more catastrophic results when they do land in the vault box from the higher heights attempted because they are falling from a higher height. It is also possible that the elite and college pole vaulters use a higher grip on the pole and therefore have a greater likelihood of a vault box landing since the execution of their takeoff speed and technique are so critical to getting the pole to rise to vertical.

Despite the survey revealing a high percentage (84%) of at least one vault box landing in inexperienced pole vaulters, there were only a small percentage of injuries requiring medical attention. Medical attention was required in only 3% of the 2,804 participants that landed in the vault box at least once. This may be explained by the fact that most jumps being attempted at the time of injury in the survey were less than ten feet so the athletes impacted the box or ground with less force on landing. The majority of injuries occurred to the ankle, heel, lower back, and knee. Although this report focuses on catastrophic pole vaulting injuries it is clear from this survey that numerous non-catastrophic injuries occur each year from pole vaulters landing in the vault box. Based on the number of participants in the survey and their average number of years pole vaulting, it can be extrapolated that there may be over a thousand non-catastrophic injuries requiring medical attention each year from pole vaulters landing in the vault box.

High School Weight Rule

There are several possible explanations for the increased rate of catastrophic injuries from athletes landing in the vault box. In 1995 the NFHS rules committee mandated that “the vaulter’s weight shall be at or below the manufacturer’s pole rating.” (ref 1994 NFHS). This rule was instituted to encourage athletes to use a lower hand hold which should reduce the bend of the pole and lower the risk of control problems such as over-shooting the landing pad, landing off the sides, landing in the vault box, and/or the pole breading. However, the stiffer poles are more resistant to rotating to vertical. If the resistance of the pole is too great for the amount of take-off energy the pole vaulter produces, the pole vaulter become stranded and may land in the vault box. In many cases the athlete reported changing to a stiffer pole prior to the catastrophic jump in an attempt to clear a higher vault. The stiffness, length, and weight of the pole as well as the grip height in relation to the athlete’s height, weight and attempted vault height requires further research to determine safe standards.

The high school and college rules state that the front edge of the vault box shall not extend above the grade of the runway. Nonetheless, one athlete reported a warped front lip that disrupted the planting position of the pole and contributed to the injury. The front lip of the vault box needs to be carefully checked before attempting any vaults. Another situation that may place pole vaulters at risk for injury is the practice of tapping or having an assistant give the pole vaulter an upward push at takeoff to help clear the bar. With appropriate supervision this practice may be beneficial during training but can lead to a false sense of security during competition when tapping is not allowed. Pole vaulting is a complex sport and coordination of speed and power of the athlete as well as timing of pole release, in particular avoiding early release, are skills that requires significant practice, expertise, and coaching.

Effects of Deeper Standard Settings Rules

In 2003 the new high school and college pole vaulting rules also mandated that the crossbar be moved away from the vault box and further over the landing pad in an attempt to reduce vault box injuries. It is unclear why this rule change was not effective, but perhaps pole vaulters are having a harder time reaching the crossbar with a higher risk of being stranded over the vault box. The ideal position of the crossbar requires further research.

Box collar

Many pole vault landing pads do not adequately cover the area immediately surrounding the sides and back edges of the vault box. The design of these landing pads allows the pole to bend without contacting the landing pad. After 2003, the NHFS required that these exposed surfaces be covered with “a minimum of 2-inch dense foam padding (box collar)” (ref) and the NCAA required that these surfaces be covered with “a collar of 2 to 4 inches of padding of uniform thickness” (ref). Many of the vault box injuries in this study occurred when the athletes landed on the exposed surfaces surrounding the sides or back edges of the vault box or a combination of these surfaces and the vault box. In spite of the NCAA and NFHS rules requiring padding in the box collar, many facilities were in noncompliance at the time of the catastrophic vault box injury in this study. One of the authors (JJ) has also noted a high rate of noncompliance with this rule at track and field meets. Therefore, strict enforcement of this rule is important, and specific standards regarding the shock attenuation capabilities of the padding used in box collars is needed.

Preventative Strategies

There are several preventive strategies for reducing the number of vault box injuries. Enforcing the existing rules requiring the box collar use is a critical first step and writing standard specifications for the box collar and its shock absorbing capabilities is next. The use of newer materials that allow greater force absorption than the standard 2 inches of unspecified dense foam should be investigated. In addition padding the sides of the vault box as well as the bottom of the vault box may be beneficial. A one piece box collar that also extends down the side walls of the vault box would not only pad the side walls of the vault box but would also hold the box collar padding in place better. The current vault box dimensions require a flare on the sides and rear to allow space for the fiberglass pole, introduced in the 1960s to bend and rotate to vertical. However, the flare on the sides of the vault box significantly increases the area of exposed hard surface in the vault box and may not be necessary to allow the pole to bend like the rear flare in the box. Eliminating the flare on the sides of the vault box or padding the interior side walls would reduce the hard surfaces and potentially diminish the risk of injury. Another change that may reduce or eliminate vault box injuries is making the vault box narrower. Requiring spotters near the vault box has been proposed but is controversial, as they may be at risk of injury from the pole or from impact with a descending athlete.

Participation Levels Indicate Higher Risk in College than HS

In contrast to the level of participation (78% high school and 9% college) at the time of the injury in the prior study on catastrophic injuries, this study identified a higher percentage of injuries in college athletes (52%) compared to high school (40%) pole vaulters (ref). If participation numbers are accounted for, the incidence per 100,000 pole vaulters was over 12 fold higher in college versus high school pole vaulters. Similarly the average age of the injured athletes in this study was 19 years old versus 17.5 years in the prior study (ref). The older age of the injured athletes in the current study may be due to the larger landing padpreventing injuries in high school athletes, whereas older college athletes are attempting higher vaults, gripping the pole higher, and may be stranded over the vault box. Unlike the prior study which reported no injuries in female athletes, this study identified 3 injured female athletes. This is likely due to the increased participation by females in pole vaulting over the past decade.