Mr. Sudheer L Karlakki
MBBS, FRCS(Ed&Gl), FRCS(Orth), Msc(Orth Eng), LLM (Med Law)
GMC membership number: 4340252
Consultant Hip & Knee
Replacement & Revision Specialist
Honorary Senior Lecturer
Robert Jones & Agnes Hunt Orthopaedic Hospital, Gobowen, Oswestry
01691 404344 & 07384 277867
General Information
Osteoarthritis is a medical term used to describe general wear and tear of a joint associated aging but not necessarily old age alone. Common symptoms are activity related pain and progressive stiffness in the joint. The onset of symptoms can vary from one individual to another, in other words symptoms and the onset of arthritis can start as early as 40 or maybe as late as 80. Although symptoms generally correlate with arthritic changes on the x-rays, the level of symptoms experienced can vary based on the pain sensitivity and other factors such as activity. Additionally, the symptoms can also be heightened by pain associated with the soft tissues in and around the joint.
Conditions such as rheumatoid arthritis or Psoriasis where body mounts an immune or inflammatory response to own cells. Joints are ivolved due to extensive inflammation in and around the joint, in other words the joints are secondarily affected, this is referred to as inflammatory arthritis.
Inflammatory symptoms are typically worse at night and aching in nature.
The bones are the basic block works of the body forming the skeleton. Joints are the pivot points for the limbs to move about from. The ends of the bones in the joint are covered by strong cartilage namely, ‘articular cartilage’ to help frictionless movements. This is often further facilitated by additional cartilages such as a ‘meniscus’ in the knee. The joints are held together by a very strong capsular tissue and capsular ligaments and further strengthened by ligaments inside the joint, such as ‘ligamentum teres’ in the hip and ‘cruciate ligaments’ in knee; and outside the joint, ‘ileofemoral ligament’ in the hip and ‘collateral ligaments’ in the knee. Muscles are the pulleys for the limbs, they are attached to the bone by becoming tendons.
This structure is then controlled through a very complex nervous system controlled by the brain, with various sensors for pain, pressure, position and force, in and outside the joint via sensory nerves, and muscles contractions via motor nerves. These nerves originate from the spine and travel down to respective sensors and motor units in the muscle.
What may appear to be pain that is from an arthritic joint alone can be a due to combination of factors such as pain from a worn arthritic joint, pain from surrounding soft tissues such as joint capsule, ligaments, tendson and muscles. The success of a joint replacement therefore depends on whether or not most of the pain is from the worn arthritic joint alone, this however may be difficult to establish and identify before surgery especially in the presence of very painful arthritic joint.
Occasionally the pain may be extrinsic or outside the joint but felt as from the joint, this is called ‘referred pain’. The brain essentially confuses origin of pain from one structure to the other. For example, the Hip pain can be sometimes felt as Knee pain, as sensations around both joints are carried by the same sensory nerve.
Radiating pain is the pain that starts at a point usually above and travells down, typically back pain down to outside of the hip or along the leg due to arthritic small joints or facet joints in the lower back. Similarly neck pain down the shoulder and arm. Best example being Sciatica.
Arthritis is a progressive condition. The natural course is one that of gradual deterioration. After an initial painful period, the symptoms can settle and remain settled for a long period before gradually getting worse. The symptoms can also be intermittent. The speed at which the joint deteriorates and the amount of pain that one experiences can vary enormously from one person to another.
This is essentially non-operative management of arthritis. To begin with avoiding excessive activities, especially impact loading activities such as running, controlling weight, taking painkillers and anti-inflammatories. These often improve symptoms to enable day to day activities without significant pain.
Short course of anti-inflammatories for a few weeks often help to settle the inflammation and therefore pain. Significant inflammation in the is often sensed as night pain, just like a tooth ache.
Its better to try nonoperative management as it may control and settle initial excerbation of sysmptoms, which may remain settled even after stopping medication for a long time.
Unfortunately, all medicines carry a degree of side effects, this needs to be weighed against the benefits The simplest analgesia is Paracetamol which is a weak painkiller. One is restricted to a total of 8 tablets (4gms a day). Paracetamol does carry a risk of liver damage. Prolonged used without discussion with your GP is not advisable as with any other medication.
In the early stages of arthritis when there is quite a lot of inflammation from wear debris in the joint, anti-inflammatories do work very well. There are a variety of anti-inflammatories. Common side effects associated with anti-inflammatories are gastric irritation (heart burn), prolonged use can result in kidney and heart damage, therefore prolonged use without medical supervision is not advisable. If you suffer from any of these conditions you must avoid taking them without medical supervision.
In inflammatory arthritis like Rheumatoid Arthritis, controlling the inflammation has a positive effect in delaying or slowing down the process of wear and tear and deformities of the joint.
The same can be extrapolated to the initial stages of arthritis, where the pain is mainly due to inflammatory response to wear debris from a wearing joint due to aging. This inflammation although often settles with time, excessive inflammation can secondarily damage the joint as in inflammatory arthropathy. Therefore, a course of anti-inflammatories for a period until symptoms remain settled will have a significant benefit in not only controlling the symptom but possibly avoiding aggressive wear in the joint.
The simple answer is when the symptoms are directly attributable to arthritis of the joint, all of the non-operative measures have been exhausted, X-rays reveal corresponding changes and you have reached a point where a reasonable expectation of a quality of life is significant affected.
In choosing surrgery one has to weigh up benefits against the risks, this decision is individual and therefore variable. Several factors such as the efffect of pain, limitation of function, age, preogression of arthritis and expectations on quality of life affect this decision.
Generally speaking surgery remains the last choice in treatment of arthritis.
True:
There are different approaches to the hip joint, This is largely dependent upon surgeon's training. Almost all of these will involve cutting through skin, and some form of tendon and some instances part of the muscle. Every approach has its benefits and risks. One has to balance the benefits against the risks.
Having tried all of the various approaches to the hip joint over the years, I routinely use what is referred as the 'posterior approach', this allows minimal cutting through skin (minimal incision surgery), good exposure and visualisation, lends itself to difficult complex scenarios, future surgeries and carries minimal risk. It is argued that the risk of dislocation is marginally higher, however with your help and care, this can be virually eliminated.
Frequently asked question is regarding 'resurfacing of the hip', firstly this is a metal on metal hip and secondly not an intermediate procedure, in other words it is form of hip replcement. advanatges are that the bearing surfaces are larger, closer to anatmy and therefore theoretically near normal function. Being a metal on metal hip it carries issues and concerns regarding metal debris and metallosis. Although it has its place in certain circumstances, it is unsuitable in most due to benefits not necessarily outweighing the risks!. I no longer offer this in my practice.
The issue of exposure is less in knee replacement. However the debate is about Partial Vs Total Knee replacment. Although a selected group will benefits from partial knee replacment, the main beneifit being a better range of movement and stability when rest of the knee and ligamants are intact, the failure rate howver is higher and also they may not always address all of the pain if the arthritis affecs more than one part of the knee. Debate is ongoing.
Almost all hospital and surgeons have adopted "enhanced or accelerated recovery". It essentially allows you to feel well soon after surgery. These changes are brought about by changes largely to anaesthetic practices and pain management and also to the surgical techniques. Pre-education is a huge component of this process.
The main advantage is it allows you to go home to your familier surroundings sooner from hospital. It is not to be confused with early healing, healing is slow process over the months.
If you were able to go home the same day it is referred to as 'Day case Hip replacement'. Although this is possible in a younger able bodies person, this may be difficult in less physical able and a person with medical issues as some of the issues may not be apparent or arise till a couple of days later and home may not be a suitable place.
Both Hip and Knee replacements are two of the most effective orthopaedic operations in the right circumstances for the right reasons. Main benefit is pain relief and restoration of day today function, activity and to an extent, sporting activiies. Surgery in the right circumstabces can be life changing.
Joint replacements are major surgeries and naturally associated with risks. The downsides of an artificial joint are that they are inferior our own natural joints in terms of function and movements also lack self-healing properties. Therefore wear and loosen with time requiring further surgery expected and depends ones activity and life expectancy
Complications of surgery range from simple superficial wound infection to serious complications such as deep infection requiring re-operation, life threatening pulmonary embolism (PE), heart attack (MI) and stroke (CVA) and a 30-90 day mortality risk up to 0.02-0.05%.
Serious complications are generally less than 2% and life threatening complications are less than 0.5%. As the surgery involves cutting of bones with power tools, there is a small risk of unintended fractures, injuries to nerves and blood vessels, these risks are further influenced by anatomical abnormalities, previous surgeries, obesity and contractures around the joint.
As with any major surgery any of the vital organ failure can occur for various reasons, often precipitated by underlying medical conditions, sometimes only apparent after surgery under the physiological stresses of surgery. All patients undergoing surgery will go through rigorous pre-operative assessment to check and optimise the success following surgery.
Deep Infection
The risk of deep infection is generally between 0.5 to 1%. This is a serious complication and generally requires further surgery and the chance of curing the infection depends on several factors such as the nature of the bug, general condition of the person and vary between 80 to 85%. In other words, the risk of persisting infection is 15%.
The risk of DVT and pulmonary embolism
The risk of apparent DVT is anywhere between 10 to 15%. The risk of pulmonary embolism is generally less than 1%. Deep venous thrombosis can result in persistent swelling and occassionally skin ulcerations in the leg. Pulmonary embolism (blood clots in the lung) can be serious and occasionally fatal. Mechanical preventative measures such as foot pump or calf pumps will be utilised during and after surgery, whilst in bed and until one is fully mobile. One is encouraged to mobilise as soon as possible following surgery to minimise this risk. You will be put on Heparin injection or an alternative following your surgery. You may require a stronger blood thinning medication such as Warfarin if you have had previous blood clots.
Heart attack
This risk is less than 1%; this largely depends on any underlying hidden cardiac issues which may be aggravated by the stress of surgery. A thorough pre-operative assessment generally picks underlying cardiac issues, sometimes it may not be apparent until stresses of surgery precipitate this.
Stroke
The risk of stroke again is less than 1%. This risk is higher if there is a previous history. We generally avoid performing major surgeries for at least 6 months following a previous event to minimise this risk.
Confusion
Transient confusion following a major surgery is not uncommon, especially if one is known to mild confusion at times or has a history of dementia. This risk is higher with advancing age. Although often transient may take a long while to recover and sometimes may gradually worsen.
Smoking and Alcohol: Stopping smoking and reduce alcohol intake, this has an enormous influence on healing.
Excessive weight: Weight management and reduction of weight where necessary, reduces your complications related to heart, lungs and blood clots and improves ease of surgery and wound healing.
Known medical conditions: Compliance with medications for known medical condition and checks with your GP, reduces specifics risks relating to these conditions, for example diabetes.
Bowel habits: It is not uncommon to have constipation with codeine based pain medication, medication when necessary for regularising bowel movements reduce risks related to bowel obstruction.
Shower/bath: Shower or bath before surgery: It is important reduce the risk of infection and it is something you can help with.
Alternative Medication: If you are on any over the counter medication you must tell us before surgery, some of these can cause serious bleeding.
Dissatisfaction
The risk of dissatisfaction following hip replacement may be as high as 5-10%. This is can be due to complications, persisting pain from soft tissues, particularly pain around the outer aspect of the hip joint, referred pain from lower back and pelvic joints and sometimes due to excessive expectations.
Leg length discrepancy
Most patients will have a minor leg length discrepancy following hip replacement. This is necessary to ensure that the hip is adequately tensioned within the limitations of the design of the implant. Most surgeons would aim to get this as close to the natural length as possible. In cases where there is preexisting descrepency (leg length discrepancy in the general population is about 10 to 15%), it may be difficult to get it equal to the other side.
It is also natural to feel the operated leg to be longer soon after the operation until you can fully weight bear and improve the weakened muscles around the hip joint.
Dislocation
The risk of dislocation is anywhere between 1 to 3%, this depends on the positoning of the implant during surgery and your compliance with the restriction to movements after surgery until the soft tissues have healed and strengthened.
Dissatisfaction
Various studies quote that up to 20% of patients are not happy with their knee replacement. The reasons for this are many, knee is a complex joint and held together with complex ligament structures. No knee replacement will result in normal mechanics or feel of a normal knee, therefore expectations that a replaced knee will be as good as a natural joint is often the main reason for dissatisfaction. Pain and swelling often lasts longer than a hip replacement and the healing can take much longer, even over a whole year. The pain mechanism is also complex, persistent noticeable pain from the soft tissues (capsule of the joint) may be as high 10%.
Persistence of numbness on the outer aspect of the scar is normal and can be a nuisance to some. Roughly 30% patients cannot knee after knee replacement, the reasons for this are again complex and ill understood.
A small number can develop excessive scarring resulting in Stiffness and occasionally deblitating Chronic Pain. This risk is small usually less than 1%.
All implants do wear out with time just like any bearing. The wear particles induce an inflammatory response from the body resulting in loosening of the implant from the bone surface.
This wear of an artificial joint depends one’s activity, nature of the activity to some extent, inflammatory response from one’s body to the wear particles and the type of wear debris produced by the artificial joints. The rate at which they wear is proportional to the activity. In someone who walks 2 or 3 miles a day (day today activities), the risk of failure as a result of the implants wearing out and loosening is about 5 – 10% over a period of 15 to 20 years. However, this risk may doubled at 10% at 10 years in someone who is young and active where naturally the amount of activity will be at least twice the above.
Implants are fixed to the bone either with cement (cemented) or with a tight fit (uncemented). In cemented joint replacement cement is used as a grout to secure the implants to bone. In uncemented joint replacement implants are placed inside the bone by a tight fit, these implants have a coating or a surface to encourage bone ingrowth to promote biological integration of the implant to the bone.
Across Europe and United Kingdom, nearly half the hip replacement are uncemented and across North America, almost all are uncemented. As far the knee replacement, most are cemented across the world.
In my practice hip replacements are mostly uncemented, this to promote biological integration and to minimise excessive bone loss that occurs as the implants wear and fail as in cemented replacements. There are specific issues with uncemented implants as well, there is a small risk of fracture as it requires a tight fit to ensure stability, removal of these implants can sometimes be difficult if a early revision is needed for infection.
Knee replacements are generally cemented as the cut surface of the bone is such that the initial fixation and biological integration is difficult to achieve without cement, and the risk of early failure of uncemented kneees outweighs any long term benefits. In my practice knee replacements therefore are cemented.
The surfaces that move on each other are referred to as bearing surfaces. Traditionally these are metal on a medical grade high density plastic or polyethylene.
In a hip replacement, where we anticipate higher wear a ceramic ball instead of a metal ball may be utilised as the cermic ball is highly polishable and scratch resistant. Ceramics are more expensive. Ceramic on ceramic bearing may be an option in younger patients. The advantages being, these are harder wearing, we can use a larger ball without risking higher wear, therefore more stable against dislocation and could last longer. On the other hand, the long term evidence on newer ceramic articulations are limited to about 12 years and ceramic bearings do carry a small risk of fracture and occasional squeaking, the risk of which is about 5 in1000. Ceramic fractures can be catastrophic requiring a major revision or redo surgery, this needs to be factored in when deciding on a ceramic on ceramic hip replacement.
Previously we (I have too) have used metal on metal hips, resurfacing is a metal on metal hip. Although these facilitate high activity and movement, they do increase metal ion levels in the body, significance of which is not yet well understood, but range from a small risk localised catatrophic soft tissue reaction to possible systemic effects on heart, blood cells etc. A small group of implants and sizes do increase this risk, especially in women and therefore seemingly fallen out of favour.
In a knee replacement, the bearing surfaces are mostly polished metal on high density medical grade plastic or polyethylene. The implants are generally made of Cobalt Chrome with a sandwiched medical grade plastic or polyethylene. There are ceramic coated metal surfaces, the effectiveness and longevity of these implants are yet to be realised. The use of ceramic knee replacements in a western world in a knee replacement is still yet to be tested.
This is an area where opinions differ considerably. It is not known as to whether a skin allergy to a metal is the same a s sensitivity to metal implant inside the body. A skin allergy is a different biological process as compared to a body’s reaction and rejection to a metal inside the body.
Most allergies are to nickel. If you are allergic to nickel, in a hip replacement this is often a straight forward soluation as we can utilise uncemented implants which are made of titanium and do not contain nickel, and this is largely my practice. Cemented hips on the other hand are made of medical grade stainless steel or cobalt chromium and will contain a small amount of nickel, the potential for implant rejection on account of metal allegory remains questionable.
In a knee replacement, this is somewhat difficult. On the femoral side (thigh bone) the implant material is usually a cobalt chromium to enable highly polished surface and will contain small amount of nickel. On the tibial (leg bone) side implants are made of cobalt chromium, titanium, or completely made of plastic. There are some femoral implants that have a ceramic coating. In cases of severe allergy there are options of chemical coating of metal known as ‘nitride coating’ to minimise this risk, this is an expensive process, the size of the implant often needs to be decided ahead of time, therefore taking away the freedom of fine tuning of size of implant at the time of surgery thus potentially compromising the outcome of surgery. Ceramic coated implants for routine use can be expensive, may not fit in with surgeon’s normal practice.
The problem is, up to 5-10% of the patients can have a degree of persisting pain following knee replacement, the reasons for this are complex, somewhat ill understood and often are related to soft tissues are around the knee. Therefore, under the circumstances where one is mildly allergic to nickel, considering the reaction to metal on the skin and inside the body are different, it is probably best that your surgeon sticks to an implant that he knows well rather trying a new implant or an implant with coating and further constrained by sizing options where the benefits may not outweigh the potential additional risks.
Where one is severely sensitive to nickel, coating an implant (nitrite coating) may be a reasonable solution rather than using an implant that one is not used. Please ensure that you tell and discuss this with your surgeon.
Wound healing: Post operatively, the primary aim is to ensure the wound is healed and sealed, this is to prevent contamination and secondary infection leading to deep infection. If your wound continues to leak after surgery, especially beyond 2 weeks you will need to be seen in the hospital and by the Surgeon to ensure that appropriate measures are taken to prevent further complications.
Leg swelling: Leg is usually swollen on the operated side after the surgery; this can be up to 6 weeks to 3 months following surgery. Swelling is usually more likely in knee replacements. A simple measure to control the swelling is to elevate the foot end of the bed by placing a bolster or pillows under the mattress and sleep with the leg elevated higher than the heart. it may be necessary elevate in bed during the day time, 2 to 3 times for half an hour to an hour depending on the amount of leg swelling.
In my opinion elevation of leg on a stool whilst sitting, is perhaps best avoided as this tends to keep the knee stiff and does not necessarily reduce the swelling. Sitting with leg down helps to mainain the bend which is assisted by gravity.
Swelling both legs: Usually indicates a central problem relating to heart, loss of protein and anaemia, it is best to consult GP for a check.
Breathing difficulty: It is important to seek urgent medical attention as this can be serious and related heart (heart failure or heart attack) or lungs (chest infection or blood clot or Pulmonary Embolism in the lungs).
Deep Vein Thrombosis and Pulmonary Embolism: You will be sent home on blood thinning medication or injection for a period of time following surgery. Leg Swelling that is resistant to elevation and when associated withpain often indicates a possibility of deep vein thrombosis (DVT) and you may need to be seen either by the GP or by the treating hospital to confirm this, and if proven positive you may need an extended course of medication to thin your blood. The risk of DVT is generally minimised by staying as active and mobile.
Physiotherapy: The need for physiotherapy is minimal in a hip replacement, especially in the first 6 weeks, keeping mobile and walking as best as possible and simple expercises that are shown prior to discharge is sufficient. In a Knee replacemet supervised physiotherapy is somewhat essential to gain desired bend in the knee.
Leg Lenghts: It is not uncommon to feel the operated leg to be longer after surgery. The reasons for this are many i) degree of minor lengthening, that may be necessary to stabilise the replaced hip to avoid dislocation ii) weakened muscles from an arthritic painful joint iii) a pelvic tilt induced by the swelling in the muscles and the soft tissues around the hip joint following surgery. This feeling usually starts to settle after 6 weeks when you can fully weight bear and improves over 3 months as the muscle strength and swelling in the tissues improve.
In my practice, after surgery, you will be placed on crutches for a period of 6 weeks.and stay partially weight bearing until the 6-week review, this is to allow the soft tissues to repair, heal, strengthen and the implants to bed in.It essential to avoid excessive flexion or bend beyond 90 degrees at the hip joint to prevent excessive stretching of the soft tissue repair, which can lead to a dislocation of the hip joint. Dislocation is very painful, usually require anaesthetic to put the hip back in, and has a potential to develop recurrent dislocation requiring further major or revision surgery.
A simple way of knowing this limit, is by placing a corner of a book between your belly and the thigh, an activity that requires bend beyond 90 degrees will squash the book.
A simple way to follow this is to place the operated leg forwards before seating or before getting up, you will be forced to use the chair hands rather than bending too far forwards.
Although process of healing starts as early as a week following surgery, the strengthening of the repair is a slow process and takes well up to 3 to 6 months to gain 30 to 50% of the initial strength. Disloction of a hip is potentially a preventable complication and after all as we expect the new hip to function well and last many years, a few months of initial care is worth considering to avoid this complication.
You can walk as much as your pain would permit from the day 1, at 6 weeks, post-surgical visit you will be shown exercises to strengthen your muscles and improve your balance and gait. Activities such as tying shoelaces, putting on socks without a stocking aid is best avoided for 6 months.
There is no restrictions after the 6-month of provided that the initial instructions are carried out well. One can return to most sporting activities bearing in mind that the wear is proprtioanl to level of activity including walking.
You will be referred to physiotherapy for supervised exercises. The 2 main aims following knee replacement are, firstly to strengthen your quadriceps muscle and achieve complete straightening of the knee and secondly to bend the knee to 90 degrees and beyond. The amount of bend that you can achieve following a knee replacement depends on the bend you had before surgery and the design of the implant.
managing swelling is the key to achieve good wound healing and bend. Easiliy done at night by lying flat with foot end of matress elavated, leg higher than heart. It may be necessary to eleavte in bed during the day once or twice for a period if there is excessive swelling.
Most patients achieve a bend of 90 degrees and beyond, this can take up to 3 months to a year following surgery. It is advisable to avoid excessive exercises following a knee replacement as this can cause irritation and excessive scaring leading to stiffness. This, however this is a fine line and dependent upon the individual patient and the response of the body to an operation. Persistent swelling in the leg that is not improved by elevation in bed may need attention to rule out a DVT.
Healing in knee replacement generally more prolonged than hip replacement. The knee will remain warm at night for up to 3 months and this is due to the healing which is essentially an inflammatory process. The knee will continue to improve over a whole year, sometimes beyond a year.
Once the initial pain and swelling in the knee settles at about 6 weeks, you can increase your activity based on the residual pain and swelling including return to sports such as golf, bowling etc.
30% of patients find it difficult to kneel following a knee replacement. This is largely due to the soft tissue scarring inside the knee, not just the skin scar by itself. Wearing padding around the knee, or kneeling on a cushion to begin with often helps this process to get used to kneeling.
When can I drive?
After about six weeks, once the pain is better, with appropriate precautions and ensuring you are safe to others on road users.
When can I sleep on my side?
After six weeks following hip replacement,no particular restriction following knee replacement.
How much can I walk?
As much as the pain permits with usual precautions. The distance should improve with time, pain usually an indicator of limit.
When can I swim?
After about six weeks following joint replacement (avoid breast stroke for 3 months in hip replacements).
What activities can I undertake following my hip and knee replacement?
There are no restrictions to any activity after about 6 months following hip replacement and at about 3 months following knee replacement. It is advisable however that you avoid running or jogging as these are impact loading exercises and can result in your implant working loose earlier.
Sexual Activities:
Generally after 6 weeks with usual precautions against excessive bending at the hip, perhaps a little earlier after knee repalcement.
To achieve a good result following a joint replacement, the following 3 are a key:
1. Indication - Pain that is largely attributable to a worn or arthritic joint
Best results are achieved when all or nearly all of the pain is from the worn joint. Pain from surrounding soft tissues such as ligaments, tendons, muscles and referred pain from lower back will influence the eventual outcome.
2. Conviction - Surgeon and Patient
All joint replacements wear with time. Generally speaking its the first joint replacement has the best chance of lasting the longest, therefore the surgery needs to be performed with total conviction by the surgeon and similarly the post-operative compliance by the patient.
3. Patient factor
Every person is unique, patient factors do influence the recovery and outcome. Expectations realistic and tailored to the replaced joint which is inferior to biological joint both in terms of function and longevity.