Complex regional pain syndrome type 1 (CRPS-I) is a devastating complication that can occur after limb extremity injuries. The effectiveness of vitamin C in preventing CRPS-I incidence is debatable. Therefore, we conducted a systematic review and meta-analysis to assess the role of vitamin C in CRPS-I prevention and its effect on pain score, functional outcomes and complications rate after wrist, ankle, and foot fractures. We searched Medline, Embase, the Cochrane Library, . Clinicaltrial.gov. , and Google Scholar from infinity to May 2021 for relevant studies comparing the incidence of CRPS-I with administration of perioperative vitamin C versus placebo after wrist, ankle, and foot fractures. Continuous data such as functional outcomes and pain scores were pooled as mean differences (MD), whist dichotomous variables such as the incidence of CRPS-I and complications were pooled as odds ratios (OR), with 95% confidence interval (CI). Data analyses was done using R software (meta package, version 4.9-0) for Windows. Eight studies, including two quasi-experimental studies, were included. The timeframe for vitamin C administration ranged from 42 to 50 days post-injury and/or surgical fixation and the dosage was either 500 mg or 1000 mg. The results showed that vitamin C was associated with a lower rate of CRPS-I relative to a placebo (OR 0.33, 95% CI [0.17, 0.63]). No significant difference was found between vitamin C and placebo in terms of complications (OR 1.90, 95% CI [0.99, 3.65]), functional outcomes (MD 6.37, 95% CI [-1.40, 14.15]), and pain scores (MD -0.14, 95% CI [-1.07, 0.79]). The findings demonstrate that when compared to placebo, at least 42 days of vitamin C prophylaxis is associated with prevention of CRPS-I following wrist, ankle, and foot fractures, irrespective of vitamin C dosage or fracture type. No significant differences were found with secondary outcomes

Diagnosis of complex regional pain syndrome (CRPS) can be challenging. We explore the role of fracture clinic in diagnosis and management with a closed-loop audit of new guidelines. We retrospectively reviewed patients with CRPS over 3.5 years. We determined the delay from injury to commencement of treatment and monitored symptoms. New guidelines were introduced to fracture clinic in January 2013. The Budapest Criteria aids diagnosis. GAD-7 and PHQ-9 patient questionnaires grade symptoms. Orthopaedic surgeons prescribe nortriptylline or pregabalin, refer to physiotherapy and review patients after six weeks. We re-audited prospectively after implementing these guidelines. The first audit cycle found 11 patients in 3.5 years. The mean delay to anti-neuropathic medication from injury was 4.7 months. Two patients required psychotherapy, one intravenous pamidronate, three inpatient physiotherapy under nerve blocks and two spinal cord stimulators. After implementing guidelines, there were 14 patients with CRPS in 9 months. All but two patients received anti-neuropathic medication on the day of diagnosis. All patients treated appropriately improved markedly within 4–12 weeks. No patients required escalation of treatment. Our guidelines increased pick-up rates of CRPS, diagnoses were made earlier and treatment started sooner. Physiotherapy modalities remained varied, however, early anti-neuropathic treatment led to a rapid improvement in all cases

There are two types of pain, mechanical and non-mechanical. Mechanical pain hurts with movement/use, is not constant and is helped by morphine-type products. Non-mechanical pain is different. It is present 24 hours a day, often worse at night, and except for the pain of infection, is not relieved by morphine-type products. If the cause of mechanical pain can be determined, it can be corrected by an operation. The usual cause of postoperative mechanical knee pain nowadays is multifactorial, i.e. a combination of minor errors, none of which on their own would require revision. Non-mechanical pain, other than infection, is much more difficult to handle. The commonest cause is not really a pain complaint, it is disappointment due to a failure of expectation. It does not matter how often you tell patients, some patients still think they should step in a drive away. A lot of these failures of expectations become much more realistic by the end of year one. There are several other categories. Incipient osteoarthritis or sensitive people (The Princess and the Pea). If the pain complaints were severe with minimal arthritis, an operation is not likely to help. The patient on disability for no clear reason is unlikely to get a good result and Workmen's Compensation Board and motor vehicle accident patients are also a very bad prognostic sign and will often produce the postoperative painful knee. Preoperative use of large doses of morphine is also a very bad sign. It is not clear if it is the morphine, which influences the patient or the patient, who influences the morphine. There are several pain syndromes, some of which are purely psychiatric such as Conversion Disorders and Somatoform Pain Disorders. Treatment of purely psychiatric conditions should be a referral to a psychiatrist is in order. Complex regional pain syndrome is an organic pain disorder. Type 2 is causalgia or an actual nerve injury. This is unusual following knee replacement other than the odd drop foot, which even after recovery, leaves an area of dysaethesia on the dorsum of the foot. Type 1 used to be called reflex sympathetic dystrophy. This is not uncommon after total knee replacement. I managed to collect more than 40 cases. One problem is that the diagnosis to some extent is a diagnosis of exclusion. If the diagnosis can be made, then treatment is available including Cymbalta, Lyrica or Gabapentin. I have found most success with lumbar sympathetic blocks, but it is difficult to find someone, who can do these. Some patients have been treated with implantable electrical spinal stimulators with variable results. The current flavour of the month pain syndrome is called central sensitization. The theory is that if someone has pain for more than six months, then there will be changes in the brain, which will remain after the original pain goes away, hence, the title the pain in the brain syndrome. If this theory were correct, then we as arthroplasty surgeons have been collectively wasting our time for the last 40 years as no patient would have recovered. The likelihood, therefore, of this theory having any basis in reality is pretty remote. Fortunately, by the end of year one, the vast majority of our knee replacement patients are reasonably content with the procedure

In years past, the most common reason for revision following knee replacement was polyethylene wear. A more recent study indicates that polyethylene wear is relatively uncommon as a cause for total knee revision counting for only 10% or fewer of revisions. The most common reason for revision currently is aseptic loosening followed closely by instability and infection. The time to revision was surprisingly short. In a recent series only 30% of knees were greater than 5 years from surgery at the time of revision. The most common time interval was less than 2 years. This is likely because of the higher incidence of infection and instability that occurs most commonly at a relatively early time frame. Evaluation of a painful total knee should take into account these findings. All total knees that are painful within 5 years of surgery should be assumed to be infected until proven otherwise. Therefore, virtually all should be aspirated for cell count, differential, and culture. Alpha-defensin is also available in cases in which a patient may have been on antibiotics within a month or less, as well as cases in which diagnosis is a challenge for some reason. Instability can be diagnosed with physical exam focusing on mid-flexion instability which can be usually determined with the patient seated and the knee in mid-flexion, with the foot flat on the floor at which point sagittal plane laxity can be discerned. This is also frequently associated with symptoms of giving way and recurring effusions and difficulty descending stairs. A new phenomenon of tibial de-bonding has been described, which can be a challenge to diagnose. Radiographs can appear normal when loosening occurs between the implant and the cement mantle. This seems to be more common with the use of higher viscosity cement. Obviously this is technique dependent since good results have been reported with the use of high viscosity cement. Component malposition can cause stiffness and pain and relatively good results have been reported by component revision when malrotation has been confirmed with CT scan. When infection, instability and loosening are not present, extra-articular causes should be ruled out including lumbar spine, vascular compromise, complex regional pain syndromes and fibromyalgia, and peri-articular causes such as bursitis, tendonitis, tendon impingement among others. One of the most common causes of pain following total knee is unrealistic patient expectations. Performing total knee replacement in early stages of arthritis with only mild to moderate symptoms and radiographic changes has been associated with persistent pain and dissatisfaction. It may be prudent to obtain the immediate preoperative x-rays to determine if early intervention was undertaken and patients have otherwise normal appearing total knee x-rays and a negative work up. A recent study indicated that this was likely a cause or a major contributing factor to persistent pain following otherwise a well performed knee replacement. A national multicenter study of the appropriateness of indications for TKA also indicated that early intervention was a major cause of persistent pain, dissatisfaction, and failure to improve following total knee replacement

Stiffness after TKR is a frustrating complication that has many possible causes. Though the definition of stiffness has changed over the years, most would agree that flexion > 75 degrees and a 15-degree lack of extension constitutes stiffness. This presentation will focus upon the potential causes of a stiff TKR, intra-operative tips, the post-operative evaluation and management, and the results of revision for a stiff TKR. The management of this potentially unsatisfying situation begins pre-operatively with guidance of the patient's expectations; it is well-known that pre-operative stiffness is strongly correlated with post-operative lack of motion. At the time of surgery, osteophytes must be removed and the components properly sised and aligned and rotated. Soft-tissue balancing must be attained in both the flexion/extension and varus/valgus planes. One must avoid overstuffing the tibio-femoral and/or patello-femoral compartments with an inadequate bone resection. Despite these surgical measures and adequate pain control and rehabilitation, certain patients will continue to frustrate our best efforts. These patients likely have a biological predisposition for formation of scar tissue. Other potential causes for the stiff TKR include complex regional pain syndrome or joint infection. Close followup of a patient's progress is crucial for the success in return of ROM. Should motion plateau early in the recovery phase, the patient should be evaluated for manipulation under anesthesia. At our institution, most manipulations are performed within 3 months post-operative under an epidural anesthetic; patients will stay overnight for continuous epidural pain relief and immediate aggressive PT. The results of re-operations for a stiff TKR are variable due to the multiple etiologies. A clear cause of stiffness such as component malposition, malrotation or overstuffing of the joint has a greater chance of regaining motion than arthrofibrosis without a clear cause. Although surgical treatment with open arthrolysis, isolated component or complete revision can be used to improve TKR motion, results have been variable and additional procedures are often necessary

Clinical nerve injury has been reported in 0.6–4.8% of shoulder arthroplasties. Classical teaching is that 70–85% of injuries recover. Despite recovery of motor function, overall shoulder function may be negatively affected and residual pain is common. Complex regional pain syndromes may develop and become permanent. Consequently, methods to limit nerve injury have been investigated. In the early 2000's I became concerned about the incidence of nerve injuries in my arthroplasty practice. I became intrigued with the idea of peripheral nerve monitoring as a method to alert the surgeon intra-operatively about impending nerve insults so that evasive measures could be taken to prevent any clinically significant nerve injuries. The results of our first 30 consecutive patients were published in JSES in 2007. Seventeen patients (56.7%) had 30 episodes of nerve dysfunction (i.e. nerve alerts) during surgery. Twenty-three of thirty alerts (76.7%) returned to normal after repositioning the arm to a neutral position. Post-operative EMG was positive in 4 of 7 (57.1%) patients who did not have a return to normal motor latency intra-operatively and in 1 of 10 (10%) patients whose intra-operative nerve function did return to normal. None had clinical nerve injuries. This early experience indicated that nerve injury was potentially more common than previously thought but intra-operative nerve monitoring seemed to have a relatively high false positive rate. Our group subsequently studied 440 shoulder arthroplasty cases. The protocol used to identify a nerve alert was made more restrictive than the first study as an attempt to decrease the false positive rate. In this larger group, nerve alerts occurred in 185 cases (42.0%), and 37 (8.4%) cases did not have signals return to above the alert threshold at closure. There were no permanent post-operative nerve injuries and 5 transient nerve injuries (1.1%). Cases in which MEP amplitudes remained below alert threshold were significantly more likely to have a post-operative nerve injury (p = 0.03). There were no false negatives, (i.e. a post-operative nerve injury occurred while MEPs were normal at closure), making sensitivity 100%. There were 32 false positives, leading to a specificity of 92.6%, a positive predictive value (PPV) of 13.5%, a negative predictive value (NPV) of 100%, and an accuracy (ACC) of 92.3%. In my opinion, the high false positive rate and the low PPV make the technique difficult to justify for routine clinical use

Aims

Chronic osteomyelitis (COM) of the lower limb in adults can be surgically managed by either limb reconstruction or amputation. This scoping review aims to map the outcomes used in studies surgically managing COM in order to aid future development of a core outcome set.

Stiffness after total knee arthroplasty (TKA) is a common problem occurring between 5% and 30% of patients. Stiffness is defined as limited range of motion (ROM) that affects activities of daily living. A recent International Consensus on definition of stiffness of the knee graded stiffness as mild, moderate or severe (90–100, 70–89, <70, respectively) or an extension deficit (5–10, 11–20, >20). Stiffness can be secondary to an osseous, soft tissue, or prosthetic block to motion. Heterotopic bone or retained posterior osteophytes, abundant fibrotic tissue, oversized components with tight flexion or extension gaps or component malrotation can all limit knee motion. Infection should always be considered in the knee that gradually loses motion. Alternative causes include complex regional pain syndrome and Kinesiophobia that can limit motion without an underlying mechanical cause. The evaluation of knee stiffness radiographs of the knee and cross-section imaging should be performed if component malrotation is considered. A metal suppression MRI assists in quantifying the extent of fibrosis and its location in the anterior or posterior compartment of the knee. Inflammatory markers and joint aspiration as indicated to rule out infection. Arthrofibrosis, or post-surgical fibrosis, is related to abnormal scar formation after surgery that leads to loss of motion. The cause of arthrofibrosis is multifactorial and likely related to genetic host factors. Current research is focusing on molecular signatures that may better identify patients at risk. In addition, therapeutic interventions are being studied that best prevent fibrosis and its recurrence and include the use of anti-inflammatories, corticosteroids, Colchicine, biologic medications (IL-1 inhibitors) and low-dose radiation. Early treatment of the stiff TKA includes physical therapy and manipulation under anesthesia (MUA). MUA performed within 3 months may have the greatest increase in ROM but notable improvement can occur up to 6 months after TKA. After six months, arthroscopic or open surgery is recommended for persistent stiffness. Arthroscopic lysis of adhesions can improve ROM greater than 1 year after index TKA. Average improvement of ROM for both MUA and arthroscopic lysis of adhesions (usually in conjunction with MUA) is approximately 30 degrees. The outcome after open lysis of adhesions are reportedly poor but current adjuvant therapies may improve these clinical outcomes as this addresses the biologic, in addition to the mechanical, basis of fibrosis. Component revision performed for component malposition and stiffness has variable outcomes but a recent study reports a mean increase in ROM of 20 degrees and a modest improvement in overall knee function. The cause of post-operative stiffness after TKA is a complex interplay of the patient, surgeon, and post-operative factors. Correct diagnosis of the underlying cause of the stiff total knee is essential to optimizing treatment outcomes. More research in needed in how to best prevent and treat the biologic risk factors and pathways that contribute to post-surgical fibrosis

Introduction. Bone loss in the distal femur and proximal tibia is frequently encountered with both complex primary and revision knee replacement surgery. Metaphyseal sleeves provide a good option for enhanced fixation in managing such defects on both the tibia and femur. We present our results in 48 patients (50 knees) with a minimum 12 month follow up (range 12 to 45). Methods. 48 patients (50 knees) who had revision knee arthroplasty for either septic or aseptic loosening. All were graded Type II or III using the Anderson Orthopaedic Research Institute (AORI) grading system of both femoral and tibial defects. A large portion of aseptic loosening revisions were for extreme osteolysis of a bicondylar knee prosthesis. Results. 52% had tibial sleeves only, 38% had both tibial and femoral sleeves and the remainder had only femoral sleeves inserted. All knee radiographs at final follow-up showed well-fixed osteointegrated components without component migration or clinically significant osteolysis. Two knees were treated with multiple arthroscopic washouts for infection. Two knees subsequently underwent manipulation under anaesthesia with good improvement in range of movement. One subsequently developed Complex Regional Pain Syndrome. No femoral or tibial components were revised. The average pre-operative Oxford Knee Score was 22 (12 to 38) and subsequently improved to 38 (12 to 45) post-operatively. Discussion and conclusions. Our early results show encouraging signs that porous titanium sleeves are a good option when managing large metaphyseal bone loss in both femur and tibia especially in revision arthroplasty. Post operative complications were low and functional outcome scores were comparable with more traditional knee revision arthroplasty techniques in the presence of bone loss

The causes of pain after TKA can be local (intra or extra-articular) or referred from a remote source. Local intra-articular causes include prosthetic loosening, infection, aseptic synovitis (wear debris, hemarthrosis, instability, allergy), impingement (bone soft tissue or prosthetic), an un-resurfaced patella and stress fracture of bone or the prosthesis. Some surgeons think that isolated component mal-rotation can be a source of pain, but component mal-rotation is rarely present in the absence of other technical abnormalities. Local extra-articular causes include pes anserine bursitis, saphenous neuroma/dysasthesias, post-tourniquet dysasthesias, complex regional pain syndrome and vascular claudication. Referred pain is most often from an arthritic hip or radicular pain from a spinal source. Patients with fibromyalgia can have persistent pain following their knee arthroplasty and should be warned of this possibility. Evaluation of the patient includes a history, physical exam, joint aspiration and plain radiographs. In selected patients, an anesthetic joint injection, bone scan, CT scan or MRI with metal subtraction may be helpful in the diagnosis. The joint aspiration should include a CBC and differential as well as an aerobic and anaerobic culture. Fungal and TB cultures are sometimes indicated. Re-operation for pain of unknown etiology following TKA is unlikely to yield an excellent result and both surgeons and patients should be aware of this probability

Persistent post-surgical pain remains a problem after knee replacement with some studies reporting up to 20% incidence. Pain is usually felt by those who do not operate to be a monolithic entity. All orthopaedic surgeons know that this is not the case. At its most basic level, pain can be divided into two categories, mechanical and non-mechanical. Mechanical pain is like the pain of a fresh fracture. If the patient does not move, the pain is less. This type of pain is relieved by opiates. Mechanical pain is seen following knee replacement, but is fortunately becoming less frequent. It is caused by a combination of malrotations and maltranslations, often minor, which on their own would not produce problems. The combination of them, however, may produce a knee in which there is overload of the extensor mechanism or of the medial stabilizing structures. If these minor mechanical problems can be identified, then corrective surgery will help. Non-mechanical pain is present on a constant basis. It is not significantly worsened by activities. Opiates may make the patient feel better, but they do not change the essential nature of the pain. Non-mechanical pain falls into three broad groups, infection, neuropathic and perceived pain. Infection pain is usually relieved by opiates. Since some of this pain is probably due to pressure, its inclusion in the non-mechanical pain group is questionable, but it is better left there so that the surgeon always considers it. Low grade chronic infection can be extremely difficult to diagnose. Loosening of noncemented knee components is so rare that when it is noted radiologically, infection should be very high on the list of suspicions. The name neuropathic pain suggests that we know much more about it than we do in reality. Causalgia or CRPS-type two is rare following knee replacement. CRPS type one or reflex sympathetic dystrophy probably does exist, but it is probably over-diagnosed especially by the author of this abstract. The optimum treatment I have found is lumbar sympathetic blocks. Perceived pain is the largest group. It does not matter what you tell the patient, some believe a new knee should be like a new car, i.e. you step into it and drive away. The fact that they have to work to make it work is horrifying. Some of this pain is actually mechanical, especially in those with no benefits such as hairstylists. Perceived pain is widespread. The classic treatise on this is Dr. Ian McNabb's book “Backache”. It should be studied by all orthopaedic surgeons, who wish to understand pain complaints. Any experienced knee surgeon will have his list of red flags or caveats. These are often politically incorrect and this information is transferred to young surgeons, usually in dim bars late at night. I will list only a few. If the patient comes in with a form asking for a disability pension on the first visit. If the patient's mother answers the questions. If the patient comes in taking massive doses of opiates. If the patient is referred to you by a surgeon, who does more knee replacements than you do. There is also the recently described Fern Silverman's syndrome

Background. Nonsurgical treatment of Acromioclavicular joint dislocations is well established. Most patients treated conservatively do well, however, some of them develop persistent symptoms. We have used two different surgical reconstruction techniques for Chronic ACJ dislocation stabilization. The study evaluates the effectiveness of a braided polyester prosthetic ligament and modified Weaver-Dunn reconstruction methods. Methods. 55 patients (mean age 42) with Chronic Acromioclavicular joint dislocation were included in this study. They were treated either by a modified Weaver-Dunn method or a braided polyester prosthetic ligament. Patients were assessed using Oxford shoulder score preoperatively and a minimum of 12 months postoperatively. Results. 31 patients (mean age 40, M=24, F=7) were treated by Modified WD method and 24 patients (mean age 44, M=18, F=6) by Surgilig at a mean21 and 24 months post injury. The mode of injury, presentation of symptoms, grade of injury and mean time at surgery post injury was similar in both the groups. There was a significant improvement (p<0.05) in mean pre and postoperative Oxford Shoulder score in both the groups (WD Mean preop OSS=28, postop OSS= 42, Surgilig Mean preop OSS=26, postop OSS=45). The Surgilig group returned to work significantly earlier (Surgilig; mean 6 wks, WD mean 14 wks). There were 3 failures in the WD group and 1 in Surgilig. Superficial infection was seen in 3 patients requiring antibiotics only. Most of the patients from both groups were satisfied with their result except for 3 patients, one which developed complex regional pain syndrome and two developed secondary shoulder problems resulting in ongoing pain. Conclusions. Chronic ACJ dislocations can be successfully treated surgically by either Weaver-Dunn or Surgilig based on similar satisfaction scores amongst patients of both groups. In this study Surgilig had higher overall success rate, less incidence of failure and allowed earlier return to work

Aim. Fixation of distal radial fractures via the volar approach has become a commonly performed procedure over the past few years. This study is to highlight potential pitfalls with this ‘everyday’ procedure and to perhaps temper over-enthusiasm for plating all wrist fractures. Method and materials. 164 consecutive cases of wrist fracture treated by means of fixed angle volar fixation were looked at. In each case any recorded complication prior to completion of treatment was documented. The complications were divided into major and minor depending on the severity and long-term outcome and overall result. Results. With critical analysis there were 32 major complications: 12 required further surgery; 1 iatrogenic radial artery injury; 1 iatrogenic palmar branch of median nerve injury; 2 complex regional pain syndromes; 16 patients with less than 60 arc of movement. In addition 12 minor complications including hypertrophic scars, suture abscess and intermittent minor discomfort were also recorded. Conclusion. While volar distal radial fixation is well accepted and indeed commonly performed, the procedure is not without complications. We must pay meticulous attention to detail and technique to optimise results

Pigmented villonodular synovitis is a monoarticular proliferative process most commonly involving the synovium of the knee joint. There is considerable debate with regards to diagnosis and effective treatment. We present our experience of managing PVNS of the knee joint over a 12 year period. Twenty-eight patients were reviewed. MRI was used to establish recurrence in symptomatic patients rather than routine screening and to identify posterior disease prior to surgery. Eight patients had localised disease and were all treated with open synovectomy and excision of the lesion, with no evidence of recurrence. Twenty patients had diffuse disease, eight treated arthroscopically and twelve with open total synovectomy. Nineteen patients (95%) had recurrence on MRI, however, only five (25%) had evidence of clinical recurrence. There were no significant complications following arthroscopic synovectomy. Open synovectomy, in contrast, was associated with three wound infections and two thrombo-embolisms. Three patients had Complex regional pain syndrome. We believe diffuse disease should be treated with arthroscopic synovectomy which is associated with minimal morbidity and can be repeated to maintain disease control. Radiotherapy is helpful in very aggressive cases. TKR was used when there was associated articular erosion

Introduction. Extensor digitorum brevis (EDB) transfer is a useful method for treating chronic ankle instability in selected patients. It adds strength to the anterolateral capsule and provides proprioceptive feedback to functionally unstable ankles. Method. A single surgeon of case series of patients undergoing EDB transfer for chronic ankle instability following sporting injuries between January 2003 and July 2011 was reviewed. All patients underwent arthroscopic procedures in a day case setting. Outcomes were measured using return to sporting activity and the Karlsson functional scoring system. Results. 67 patients underwent unilateral EDB transfer over the 102 month period. 49 patients were male and all patients were aged less than 45. Minimum follow up was 6 months and all patients were discharged by 15 months (median follow up 9 months). Post operative assessment demonstrated normal range of ankle movements in all cases. At 6 months all patients had returned to sporting activity, achieving pre injury activity by 9 months. Karlsson scores were above 85.3 minor complications were seen - a superficial wound infection, limited paraesthesia of a branch of the superficial peroneal nerve and a case of complex regional pain syndrome which underwent full remission with early multimodal therapy. Conclusion. This study forms the largest published single surgeon series for EDB transfers. The data contributes to the body of evidence supporting EDB transfers as a safe and effective day case procedure for treatment of chronic ankle instability in selected patients

Persistent post-surgical pain (PPSP) remains a problem after knee replacement with some studies reporting up to 20% incidence. Pain is usually felt by those who do not operate to be a monolithic entity. All orthopaedic surgeons know that this is not the case. At its most basic level, pain can be divided into two categories, mechanical and non-mechanical. Mechanical pain is like the pain of a fresh fracture. If the patient does not move, the pain is less. This type of pain is relieved by opiates. Mechanical pain is seen following knee replacement, but is becoming less frequent. It is caused by a combination of malrotations and maltranslations, often minor, which on their own would not produce problems. The combination of them, however, may produce a knee in which there is overload of the extensor mechanism or of the medial stabilizing structures. If these minor mechanical problems can be identified, then corrective surgery will help. Non-mechanical pain is present on a constant basis. It is not significantly worsened by activities. Opiates may make the patient feel better, but they do not change the essential nature of the pain. Non-mechanical pain falls into three broad groups, infection, neuropathic and perceived pain. Infection pain is usually relieved by opiates. Since some of this pain is probably due to pressure, its inclusion in the non-mechanical pain group is questionable, but it is better left there so that the surgeon always considers it. Low grade chronic infection can be extremely difficult to diagnose. Loosening of noncemented knee components is so rare that when it is noted radiologically, infection should be very high on the list of suspicions. The name neuropathic pain suggests that we know much more about it than we do in reality. Causalgia or CRPS-type two is rare following knee replacement. CRPS-type one or reflex sympathetic dystrophy probably does exist, but it is probably over-diagnosed. The optimum treatment I have found is lumbar sympathetic blocks. Lyrica, Gabapentin and Cymbalta may also help. Perceived pain is the largest group. It does not matter what you tell the patient, some believe a new knee should be like a new car, i.e. you step into it and drive away. The fact that they have to work to make it work is horrifying. Perceived pain is widespread. The classic treatise, Dr. Ian McNabb's book “Backache”, should be studied by all who wish to understand pain complaints. Any experienced knee surgeon will have his list of red flags or caveats. I will list only a few. If the patient comes in with a form asking for a disability pension on the first visit. If the patient's mother answers the questions. If the patient comes in taking massive doses of opiates. If the patient is referred to you by a surgeon who does more knee replacements than you do. There are other issues such as good old fibromyalgia, which appears to have gone the way of the dodo. It has been replaced by something equally silly called central sensitization. The theory of central sensitization is that if one has pain somewhere or other for three months or six months or whatever, there are going to be changes in the brain and spinal cord. It then does not matter what happens to the original pain, i.e. whether or not it goes away, the pain will persist because of the changes in the brain, hence, the title of the pain in the brain syndrome. If this theory was correct, we might as well all go home because we have all been wasting our time for the last 30 years because none of our patients would get any better. After all, all of our patients have had pain for a lot longer than three months, many of them have been involved in trauma and sometimes, compensation is at issue. The pain in the brain theory, therefore, sounds about as realistic as the flat earth society or the treatment of Galileo

Persistent post-surgical pain (PPSP) remains a problem after knee replacement with some studies reporting up to 20% incidence. At its most basic level, pain can be divided into two categories, mechanical and non-mechanical. Mechanical pain is like the pain of a fresh fracture. If the patient does not move, the pain is less. This type of pain is relieved by opiates. Mechanical pain is seen following knee replacement, but is fortunately becoming less frequent. It is caused by a combination of malrotations and maltranslations, often minor, which on their own would not produce problems. The combination of them, however, may produce a knee in which there is overload of the extensor mechanism or of the medial stabilizing structures. If these minor mechanical problems can be identified, then corrective surgery will help. Non-mechanical pain is present on a constant basis. It is not significantly worsened by activities. Opiates may make the patient feel better, but they do not change the essential nature of the pain. Non-mechanical pain falls into three broad groups, infection, neuropathic and perceived pain. Infection pain is usually relieved by opiates. Since some of this pain is probably due to pressure, its inclusion in the non-mechanical pain group is questionable, but it is better left there so that the surgeon always considers it. Low grade chronic infection can be extremely difficult to diagnose. Loosening of noncemented knee components is so rare that when it is noted radiologically, infection should be very high on the list of suspicions. The name neurogenic pain suggests that we know much more about it than we do in reality. Causalgia or CRPS-type two is rare following knee replacement. CRPS type one or reflex sympathetic dystrophy probably does exist, but it is probably over-diagnosed especially by the author of this abstract. The optimum treatment I have found is lumbar sympathetic blocks. Lyrica, Gabapentin and Cymbalta may also help. Perceived pain is the largest group. It does not matter what you tell patient, some believe a new knee should be like a new car, i.e. you step into it and drive away. The fact that they have to work to make it work is horrifying. Some of this pain is actually mechanical, especially in those with no benefits such as hairstylists. Perceived pain is widespread. The classic treatment on this is Dr. Ian McNabb's book “Backache”. It should be studied by all orthopaedic surgeons, who wish to understand pain complaints. There are other issues such as good old fibromyalgia, which appears to have gone the way of the dodo. It has been replaced by something equally silly called central sensitization. The theory of central sensitization is that if one has pain somewhere or other for three months or six months or whatever, there are going to be changes in the brain and spinal cord. It then does not matter what happens to the original pain, i.e. whether or not it goes away, the pain will persist because of the changes in the brain, hence, the title of the pain in the brain syndrome. If this theory was correct, we might as well all go home because we have all been wasting our time for the last 30 years because none of our patients would get any better. After all, all of our patients have had pain for a lot longer than three months, many of them have been involved in trauma and sometimes, compensation is at issue. The pain in the brain theory, therefore, sounds about as realistic as the flat earth society or the treatment of Galileo