Biosil Limited

The PAS Prosthetic Anal Sphincter device is an inflatable, fluid filled, silicone device which is designed for the management of severe faecal incontinence in adult men and women. The device functions by reproducing the normal physiology of the ano-rectum by flattening and angulating the bowel without causing crenation, as illustrated below.

The use of the PAS Prosthetic Anal Sphincter device is contra-indicated in patients who have one or more of the following conditions.

a) In patients whom the surgeon considers to be unfit to undergo an open abdominal surgical procedure due to risks associated with such surgery, and/or the patient's medical history (physical or mental condition).

b) In patients with concurrent clinical conditions (e.g. cardiac disease) that may prove to be a contraindication to general or regional anaesthesia.

c) Where the patient's lack of manual dexterity or motivation does not permit the required manipulation of the pump to facilitate correct operation (e.g. arthritis, progressive degenerative disorders).

d) Where previous surgery may have created scarring or damage to the blood supply of the bowel which precludes implantation of the cuff in the pelvis.

e) In patients who have yet to complete growth maturity (e.g. under 16 years of age) or in patients who are unable to learn how to operate the PAS (unless the device is to be operated by carers).

f) Where the principle symptom is incontinence of liquid stool as opposed to formed solid stool.

g) In patients with pathological conditions of the bowel (e.g. disorders giving rise to diarrhoea) that can interfere with the correct function and performance of the PAS device.

h) In patients where the incontinence arises from overflow related to proximal stenosis or partial obstruction of the bowel.

i) Pathological conditions which affect rectal compliance thereby diminishing the efficacy of the PAS.

j) Patients with reduced or absent rectal sensation should be carefully considered and counselled prior to surgery due to the potential risk of faecal impaction.

The PAS device consists of three components; a sphincter cuff, a pressure regulating reservoir balloon and a control pump as illustrated below.

The sphincter cuff comprises an inflatable linear expander, which when inflated, gently flattens the bowel against a silicone cohesive gel-filled pillow. The cuff consists of a silicone cohesive gel-filled soft pillow that is attached by straps to a silicone elastomer expander. The cuff is located around the anal canal in order to achieve angulation. When the expander is inflated, angulation is achieved and continence is effected. The sphincter cuff is available in one size only.

The pressure regulating reservoir balloon provides the hydraulic pressure source to drive the system and has a sigmoid pressure-volume relationship. It is set to operate at the pressure plateau level and thus maintains a near constant maximum pressure, irrespective of inflation volume. The balloon reservoir is implanted within the pelvis and ensures that excessive pressures do not develop in the system. An implantable grade stainless steel connector links the reservoir tubing to the control pump. The reservoir is provided in one size only: 60-70mmHg

The control pump allows movement of fluid to and from the sphincter, to open (deactivate) or close (activate) the device. Implanted in a subcutaneous pocket in the abdominal wall, the pump consists of three sub-components.

The control pump is implanted in a subcutaneous pocket in the abdominal wall with the recommended site being medial to the anterio-superior iliac spine.

However, it is recognised that surgeons may favour alternative sites for the pump dependant on the characteristics of the individual patient. The pump comprises of silicone elastomer mouldings, sapphire ball valves, stainless steel springs and a stainless steel "poppet" valve.

Note : The PAS prosthesis has colour-coded tubing to assist the surgeon to make the appropriate tubing connections. The control pump tubing that connects to the sphincter cuff is white, whilst the control pump tubing that connects to the pressure regulating reservoir is clear.

The control pump is supplied with implantable grade steel tubing connectors pre-fitted. During surgery, the control pump is connected to the sphincter cuff and pressure regulating reservoir by attaching the open end of the sphincter cuff's and pressure regulating reservoir's colour coded tubing onto the control pump's connectors.

It is an option that the tubing can be secured onto the connector with permanent suture ties.

The PAS device simulates the normal action and function of the anal sphincter under the control of the patient.

The cuff of the PAS device gently squeezes the upper anal canal/lower rectum producing angulation between the rectum and anal canal which controls formed stool. In order to evacuate the bowel the patient should squeeze the bulb of the control pump 4 - 8 times. This pumps fluid from the cuff to the pressure regulating balloon. When the cuff is empty the anal canal/rectum is open allowing material to pass from the bowel. At the conclusion of evacuation the patient should press the button on the dome of the pump. This opens the pump allowing fluid to automatically return to the cuff. As the cuff refills the sphincter action is once again re-activated.

A fill port is located on top of the pump, to allow the surgeon to add fluid percutaneously into the system as necessary, without additional surgery.

The PAS device has a unique operating procedure that enables the patient to defecate without the concern of having to manually maintain the sphincter cuff in the open position. The following instructions and diagrams are intended as a guide for the deflation/inflation procedures for the PAS device.

The PAS sphincter cuff is deflated by squeezing and releasing the control pump bulb several times to remove all of the fluid from the sphincter cuff's expander. The sphincter cuff will remain deflated indefinitely, until the pump is activated to re-inflate the sphincter cuff.

The PAS sphincter cuff can be deflated EITHER by:
(a) Grasping both sides of the pump bulb with the forefinger and thumb and squeezing the two sides together as illustrated below.

OR
(b) Pressing down onto the top side of the pump bulb against the abdominal wall/pelvis to depress the top side of the pump bulb as illustrated below.

The PAS sphincter cuff is inflated by depressing the control pump's dome button against the abdominal wall/pelvis as illustrated in Figure 5. This will open the control pump's valve system and allow fluid to flow back from the pressure regulating reservoir to the sphincter cuff. It should be noted that the sphincter cuff expander will inflate steadily, taking a few minutes before it is fully closed and has re-established patient continence.

All components of the PAS are supplied sterile, processed by validated strictly controlled sterilisation cycles. Sterility is verified in accordance with relevant standards. Sterility of the implant is maintained only if the package is intact and undamaged.

For shelf life, refer to the label on the package of individual component or the box label.

Store the sterile components in a clean dry place at room temperature. For maximum protection during storage, leave the packaged components inside their dust cover boxes.

All components of the PAS are intended for SINGLE USE ONLY. DO NOT REUSE EXPLANTED PRODUCTS. DO NOT RESTERILIZE ANY PRODUCT. Explanted products should not be reused because recleaning and resterilization procedures may not adequately remove biological residues, such as blood, tissue and other matter, which could retain resistant pathogens.

The PAS device is supplied in a box containing a sterile kit consisting of the three components necessary for one implantation procedure (sphincter cuff, pressure regulating reservoir and balloon control pump).
Each component is individually packaged in a double peel pouch and labelled with the product code and lot number on its outer peel pouch for identification. Sterility of the product is not guaranteed if the package has been damaged or opened. Tear-off patient record labels are attached to the primary package. These labels are to be attached to the patients' records.
The kit is available in one size only
It is recommended that at least one additional kit is available in the theatre, to allow for inadvertent contamination or any other eventuality.
Individual components can also be supplied.

Pre-operative preparation - prior to commencing surgery it is essential that both the surgeon and operating staff are familiar with the PAS device and the steps required for implantation. In this respect the PAS device should only be used by surgeons who have had appropriate instruction in the technique of implanting the device or have attended an approved training course.

Details of forthcoming courses and application forms may be obtained from the Manufacturer.

It is imperative that meticulous aseptic technique is employed throughout the surgical procedure in order to reduce the risk of infection.

The patient should have mechanical bowel preparation prior to surgery. Deep venous thrombosis (DVT) and antibiotic prophylaxis are essential. The latter should include antibiotics which are active against aerobic and anaerobic bacteria.

The surgeon should obtain informed consent having discussed with the patient prior to surgery all recognised complications, limitations and contra-indications of the operation as described within this manual complemented by the surgeons own experience.

PAS Prosthetic Anal Sphincter comprising:
a) Sphincter Cuff comprising Pillow and Expander
b) Pressure Regulating Reservoir Balloon
c) Control Pump

A number of surgical instruments and materials are required for implantation of the PAS. It is recognised that surgeons may have individual preferences in addition to the suggested list of supplies detailed below.

Large Basic Instrument Tray
Bowel Tray
Bowl and Jug
Single Bowl
Deep bladed Debakey-Balfour Retractor
Lloyd Davis Retractor
Lahey and shod Artery Forceps

3 x 3 Way taps
3 x 20 ml syringe
1 x 50 ml Bladder Syringe
200 cm manometer line
16 gauge epidural needle
3 x 1.2mm 18 gauge cannula
Dexon mesh
160 mg Gentamicin
100 ml Urograffin 370

No 22 blade
No 15 blade
2/0 vicryl ties
No 1 silk ties
2 x nylon tapes
3/0 Vicryl W1930
2/0 Prolene W295
No 1 PDS W9967
2/0 silk W791
3/0 Monocryl W 3650.

A sterile theatre stand should be used for the handling and filling of the PAS components. It is important to ensure that the components do not come into contact with the paper or cloth drapes. Submerge the filled PAS components in a large bowl containing sterile fluid until they are ready to be implanted. Splash bowls should be conveniently positioned to enable the surgeon(s) to regularly clean their gloves during the procedure - especially prior to connecting the tubing.

WARNING: Users should be aware that excessive exposure of silicone devices to Iodine containing solutions may damage the efficacy and function/performance of the device. It is recommended that silicone devices are not submerged in Iodine containing solutions. An alternative solution should be used.

In order to avoid damage to the PAS device and the tubing by the artery forceps, the jaws of the forceps should be covered by silicone or rubber tubing (protector). It is important to ensure that the 'protector' covers the entire length of the forceps teeth. In subsequent use, care should be taken not to apply excess pressure (use only to the first notch on the forcep ratchet).

Prior to handling any of the instruments or components of the PAS device, the surgical gloves should be washed fee of powder since any dust may interfere with the function of, or even block the valves of the control pump.

The prepared components should be stored in an antibiotic solution (comprising 500ml saline and 160mg Gentamicin), until required for implantation.

The PAS device is supplied sterile and should be kept in its outer box until delivered into the operating theatre.

a) Peel open outer packaging of each component under clean, aseptic conditions, over sterile field, allowing sealed inner package to fall gently into the field.
b) Attach patient record portion of the component label to patient's chart.
c) When ready to fill the PAS device components, using aseptic technique, peel open the inner package and allow contents to drop into a sterile basin containing saline.

The PAS is prepared using sterile normal saline. All the air within the components and the tubing is removed and replaced by the filling solution. This exercise must be undertaken under strict sterile conditions and particular care must be taken to prevent surface contaminants coming into contact with the PAS device.

In the event that debris is found in the filling solution, tubing or on the PAS device components, the procedure should be recommenced using fresh solutions as any particle
may obstruct flow within the PAS device leading to its malfunction. Contaminated components should be replaced by new components.

The solution used to prime the PAS device must be isotonic with intracellular fluid in order to minimise the transfer of fluid across the semi-permeable silicone membranes of the PAS device. The recommended filling solutions are:

a) Sterile normal/isotonic saline.
b) Urograffin diluted 50ml contrast with 50ml sterile water.

Contrast media are contraindicated if the patient has a known iodine allergy.
Failure to use the recommended filling fluids may impair the performance of the device.

Experience has shown that the process of priming the PAS device is most easily achieved by using a large bowl filled with sterile saline, into which the component parts of the PAS may be submerged. After preparation, the components should be stored submerged in a Gentamicin solution (160mg/500ml sterile saline) until required for use.

In the first instance, all the air is gently aspirated from the cuff using a 20ml or similar syringe with an 18 gauge cannula. Approximately 10ml of sterile saline is then instilled into the sphincter cuff. It is important to aspirate all the air from the sphincter cuff since the presence of residual air may lead to malfunction of the device.

A useful technique to achieve displacement of all the air is to completely submerge the sphincter cuff in a bowl of sterile saline and manipulate the cuff by squeezing and releasing.

The tube leading from the sphincter cuff is then clamped close to the distal end using a shod artery forcep. The cannula is removed and the sphincter cuff is submerged in an antibiotic solution of 160mg Gentamicin in 500ml sterile saline until required for surgery.

The control pump is prepared by submerging it in a bowl containing sterile saline and by repeated cycling (activate and deactivate) any air that is within the control pump is expelled and is displaced with fluid. The use of a syringe is not required for the preparation of this component. It may be necessary to change the orientation of the control pump within the bowl to facilitate removal of all the air.

Once this step is completed, clamping with shod artery forceps seals the tubes leading from the pump. Finally transfer the control pump and artery clamps to a storage container and submerge in Gentamicin solution (160mg/500ml sterile saline) until required for surgery.

Using a 20ml (or similar) syringe with an 18 gauge cannula attached, aspirate the air from the balloon and fill it with approximately 40ml sterile saline.

Submerge the pressure regulating reservoir balloon into a bowl of sterile saline, holding the tube upright in order to facilitate evacuation of any residual air. Re-fill the balloon with approximately 40ml of the chosen filling solution. Once this step is completed, seal the balloon by applying a rubber shod artery forcep to the tubing leading from the balloon, approximately 3cm from its end.

Remove the syringe and finally transfer the reservoir balloon and artery forcep to a storage container and submerge in Gentamicin solution (160mg/500ml sterile saline) until required for surgery.

Care must be taken to prevent surface contaminants such as talc, dust and skin oils from coming into contact with the device. Products should be inspected for contamination prior to insertion. Contamination at the time of surgery increases the risk of periprosthetic infection.

Note : Textured silicone surfaces are potentially more susceptible to contamination than smooth silicone surfaces. Extra care should be taken in the handling of textured surface implants and the manufacturer/supplier accepts no liability for components contaminated by other substances after the PAS device leaves our possession.

SURFACE CONTAMINANTS (TALCS, DUST, LINT, OILS) ON SURFACE OF IMPLANTS CAN CAUSE FOREIGN BODY REACTION, HANDLE WITH CARE WITH SURGICAL GLOVES (RINSED FREE OF TALC) WITH STRICT ASEPTIC TECHNIQUE. DO NOT IMPLANT CONTAMINATED PRODUCT.

Back-up products must be readily available at the time of surgery for use in the event of
contamination.

Prior to commencing surgery, it is necessary to prime the PAS device with sterile saline. This is performed by totally submerging the components in a large sterile bowl filled with saline. The sphincter cuff expander, pressure regulating balloon and control pump are then filled with saline from the bowl using a syringe and the supplied adaptor. It is necessary to ensure that all the air is expelled from the component parts of the PAS device during this exercise. The presence of any residual air may lead to malfunction of the sphincter. Once priming is complete, the saline should be retained within the components using soft clamps (silicone or rubber shod artery forceps are ideal). All implantable components are then stored in an antibiotic solution of 160 mg Gentamicin in 500 ml saline until required for surgery.

As stated before, the recommended surgical technique described in this leaflet for implantation of the PAS device is a guide which should only be used in conjunction with supplemental instructions in the technique of implanting the device. Details of appropriate training can be obtained from the manufacturer.

Since potentially serious complications for patients may ensue from the use of incorrect implantation procedures, only appropriately trained surgeons should implant the PAS Prosthetic Anal Sphincter.

Unless contraindicated, prior to surgery, patients should be given antibiotic and deep venous thrombosis (DVT) prophylaxis.

It is mandatory that strict aseptic techniques are employed by all operating theatre personnel.

Patients should be catheterised.

Under general or other appropriate anaesthesia, a lower mid-line incision is made extending from the pubic symphysis to the umbilicus. It is necessary throughout the operation to maintain meticulous haemostasis.

A limited dissection is then undertaken of the lower rectum. An incision is made in the pelvic peritoneum lateral to the rectum on one side only. The dissection is developed to mobilise the lower rectum including the mesorectum. This is continued to the junction of the anal canal and rectum. Anterior to the rectum, the vagina (female) or seminal vesicles (male) is dissected free from the rectum. Finally, a small "window" is then cut as low as possible in the contra lateral pelvic peritoneum. This should only be of sufficient size to allow the sphincter cuff to encircle the lower rectum/upper anal canal thereby preventing subsequent proximal migration of the device.

The PAS sphincter cuff is placed at the junction of the upper anal canal/lower rectum directly above the pelvic floor muscles (levator ani).

The sphincter cuff expander is placed behind the rectum and the cuff pillow is placed in front of the rectum, behind the seminal vesicles/vagina.

The straps of the cuff expander are then secured to the front of the cuff pillow. It is important that with the sphincter cuff in the deflated position, the gap between the cuff pillow and rectum is sufficient to allow unimpeded evacuation of bowel contents. This may be measured with a "balloon " or may be estimated using the operating surgeon's index finger. The peritoneum is then closed to isolate the neo-sphincter from the peritoneal cavity.

A subcutaneous pouch is then created for the control pump, normally in the right iliac fossa above and medial to the anterior superior iliac spine. This is most easily achieved by dissecting in the subcutaneous fat from the mid-line wound.

Care is required to ensure that the skin over the pouch is of the correct thickness. It should be thin enough to allow the patient to easily palpate the operating buttons on the control pump but have sufficient subcutaneous fat to prevent any risk of ischaemia. Similarly the size of the pouch should be such that the control pump is a "snug fit".

Having placed the control pump in the subcutaneous pouch, the connecting tubes from the sphincter cuff and the pressure regulating balloon reservoir are brought through the abdominal wall from the pelvis, using an extra-peritoneal route if possible. These tubes are connected to the control pump using the colour coding to ensure correct alignment (sphincter cuff to white/balloon reservoir to clear).

The pressure regulating balloon reservoir is then allowed to lie free in the pelvis. It is important that the balloon is not constrained in any way since it has an important function in preventing the development of high pressures in the system.

Immediately prior to closing the abdomen, it is advised that the operational function of the sphincter cuff and control pump are confirmed to be satisfactory. The peritoneal cavity should be lavaged with warm sterile/isotonic saline to reduce the risk of infection. Drains should be avoided whenever possible. The subcutaneous pouch should be closed to isolate it from the main wound. Routine abdominal wall closure should then be undertaken.

a. Priming the PAS components
Problem Unable to eradicate all the air from the system		Action • Ensure that the bowl containing the filling fluid is deep enough to allow complete submersion of all of the PAS components. • Ensure that the pump is frequently cycled during preparation.



b. Total PAS device
Problem The device fails to cycle		Action • Check the connections between the components. • Check that the pressure balloon is free to expand. • If the above are considered correct with no obvious leak found, change the entire system.
Leakage from any of the components		• Replace the affected component. • In the case of the control pump, replace if there is ANY malfunction. Do NOT attempt to mechanically flush the pump under pressure since this could cause damage to the component parts leading to subsequent system failure. • In the case of the sphincter cuff, as it is difficult to flush an implanted cuff, this should be removed and re-primed OR replaced. • In the case of the pressure regulating balloon, it is easily flushed and rarely needs to be replaced.



c. Control Pump
Problem Difficulty in cycling the pump		Action • The bulb of the control pump MUST contain fluid in order to start the cycling process. • If the bulb is empty, gently squeeze the sides of the pump, which may open the valve within the pump. • It is important to ensure that an empty pump bulb is not due to fluid loss from the system. • In the event that excessive force is required to cycle the pump, all connections should be checked for kinks and / or blockages.



d. Pressure Regulating Reservoir Balloon
Problem Leaking balloon due to damage/puncture during filling		Action • Remove balloon and replace.



e. Sphincter Cuff
Problem Incorrect fit for the anal canal rectal junction.		Action • Research has shown that the single cuff size of the PAS is suitable for ALL adult patients. • The PAS is not recommended for use in children since is unknown what effect patient growth might have on the implant. • The sphincter cuff accommodates different size requirements by a strap and button adjustment. • When deflated, it should be possible to snugly place an index finger between the cuff expander and the bowel. This fitting ensures both satisfactory occlusion of the bowel when the PAS is in the closed position and facilitates evacuation of the bowel when the PAS is in the open position.

Routine post operative care for major surgery including regular observation of heart rate, temperature and blood pressure should be conducted. Hourly urine volumes should be measured for at least 24 hours. Prophylactic antibiotics should be continued for 3 days. Consideration should be given to include flucloxacillin.

When bowel sounds return and flatus is passed, aperients are commenced. The PAS control pump should be left in the OPEN position with the sphincter cuff expander deflated. This requires to be checked by daily inspection to ensure that the control pump has not been inadvertently closed and that there is no infection.

Antibiotics should only be taken as directed by the patient's operating surgeon/doctor. Patients are discharged from hospital at the discretion of the operating surgeon.

The PAS sphincter cuff is left in the open position for 6 weeks or until there is no tenderness on palpation of the control pump site.

The first activation of the PAS device must be performed under the supervision of the operating surgeon using radiological control to ensure proper function. Patients benefit from supervision during the first three to four days of use of the PAS device after initial activation. A nurse specialist may be helpful to support and instruct the patient at this time.

Patients should be offered a three monthly review appointment. In addition, they should be issued with an 'emergency' telephone number to contact in the event of any new or unexpected symptoms. In any event, patients should be instructed that they must always obtain medical advice if they develop pyrexia, rectal bleeding or lower abdominal/perineal pain.

The hydraulic fluid (saline) within the operating system may require to be topped up after approximately 2 years of use. The need for top-up is indicated by a deterioration of sphincter cuff efficacy and is effected by percutaneous injection into the fill port site in the control pump. Sterile precautions must be used for this procedure.

It may be necessary at any time after implantation of the PAS device to confirm the positioning and function of the device. Since the PAS is radio-opaque it is visible on routine X-Ray examination.

The functioning of the PAS device is most easily assessed by performing a gastro-graph and enema with radiological screening in both on and off positions.

Since the PAS device contains a small quantity of medical grade stainless steel, Magnetic Resonance Imaging (MRI) is contra-indicated.

The major recognised complications and limitations of the PAS device are listed below. Other potential complications associated with all surgical procedures should also be discussed with the patient. These include but are not limited to infection (see below), haematoma, serous fluid accumulation, reaction to medication, patient intolerance to any foreign implant and incomplete wound healing.

Infection is an inherent risk following any type of invasive surgery. Consequently, infection may occur after implantation of the PAS device. It is important that appropriate measures are taken to avoid infection including the use of strict sterile techniques and antibiotic prophylaxis. Patients should also be carefully monitored in order that infection is promptly diagnosed and treated. In the event that infection fails to respond to these measures, it may be necessary to remove the PAS device. Subsequent re-implantation may, or may not, be possible.

When considering a patient for this procedure, those who are considered to be a high infection risk - diabetics or skin infections, should be carefully counselled and appropriate measures taken to address the issue before progressing.

As with any mechanical device, the PAS device is subject to wear and tear with time. This may include component disconnection, control pump failure etc. Should such an incident occur, revision or removal surgery may be necessary. The patient should be made aware of this and advised to contact the operating surgeon without delay if any such problems are experienced.

As with any performing biomedical device that is subject to wear and tear, it is not possible to accurately predict the life expectancy of the PAS device in an individual patient. Several factors may have a significant effect on the length of time a device will remain functional in any one patient. These factors include the implantation procedure, the anatomy and state of health of the patient, the behaviour and activities (e.g. sporting activities) as well as external mechanical influences.

Although the design of the PAS device is intended to avoid the risk of tissue ischaemia, this is a possible complication of any implanted device of this type which encircles the bowel. The risk of ischaemia is increased if the sphincter cuff setting is too tight, potentially leading to pressure necrosis. Failure to timeously recognise this complication may lead to severe consequences and urgent removal of the device may be required.

Patients may experience faecal impaction after implantation of the PAS device. This is a common problem which may arise mainly due to the following reasons:

Patients may experience pain and discomfort after surgery as in any other major abdominal operation. However, persistent or excessive post-operative pain may indicate a complication and medical advice should be sought immediately.

g. Patient Expectations

It is important that patients are counselled prior to surgery so that they have realistic expectations of the physiological, psychological, physical and functional outcome of the PAS device after implantation. In particular, patients should be made aware that the PAS device is not designed to control liquid stool. Consequently, it should be advised that the PAS device will be ineffective in patients with diarrhoea.

Due to the position of the implanted device above the pelvic floor muscles there is a small "deadspace" below the device which may contain faeces after activation if patient has not completely emptied the rectum. This in turn may lead to minor leakage. With practice, the patient soon learns to avoid this.

Most patients find the pump site cosmetically acceptable but in thin patients the pump may be apparent as a small protrusion under the skin.

In the event of infection or failure of the component parts of the PAS device, replacement of individual components or the entire system may be required. However, due to post operative scarring, infection or other factors, revision surgery may not be possible and instead the entire PAS device may need to be removed.

Displacement of device components may occur if the components are not positioned correctly or if the tubing length is incorrect or if the size of the surgical pocket is unsuitable. This may cause medical complications or device malfunction possibly leading to revision surgery.

If radio-opaque solution is used to fill the device instead of sterile isotonic saline, ensure the patient is not allergic to the radio-opaque solution.

Since the PAS device contains a small quantity of medical grade stainless steel, Magnetic Resonance Imaging (MRI) is contra-indicated.

The subcutaneous pump may be subject to trauma/impact damage due to, e.g. contact sports. Patients should be made aware of this possibility. However this should not inhibit individuals from participating in sporting activities in general.