Evaluation of Pain in Patients With Apparently Solidly Fixed Total Hip Arthroplasty Components Graham M. Robbins, MB, BS, FRCSOrth, Bassam A. Masri, MD, FRCSC, Donald S. Garbuz, MD, FRCSC, and Clive P. Duncan, MB, MSc, FRCSC Abstract The cause of pain in a patient with an apparently solidly fixed total hip arthro- third of patients who fail on the pain plasty can be difficult to elucidate. A detailed history, careful examination, and rating do not fail on overall Harris plain radiographs provide the most useful information, especially in excluding or Charnley scores.3 It has been sug- causes not primarily related to the hip. Determining whether the pain is related gested that a simple visual analog to the implant, to soft tissue, or to bone can require laboratory tests, radiograph- pain score may be more accurate in ic and fluoroscopic imaging, and contrast arthrography and local anesthetic assessing outcome because it corre- injections. Particularly when pain is caused by occult infection, erythrocyte lates highly with the Harris hip sedimentation rate, C-reactive protein level, hip aspiration, advanced radiologic score.4 Also, in patients with multi- imaging, and nuclear medicine scans can help determine the diagnosis. ple joint dysfunction, reference thus J Am Acad Orthop Surg 2002;10:86-94 can be made specifically to the joint of interest. A THA Outcome Evaluation Form prepared jointly by the Hip Society, the American Total hip arthroplasty (THA) is a corrected). Mancuso et al1 found Academy of Orthopaedic Surgeons, very successful procedure, achieving that 60% of patients expected pain and the Société Internationale excellent pain relief, improvement in relief and only 7% expected an de Chirurgie Orthopédique et de activity level, and patient satisfac- increase in nonessential activities. Traumatologie attempts to address tion in 90% of cases.1 However, in Those who expected psychological the deficiencies of previous scores some patients, discomfort persists or improvement—for example, to “feel by incorporating patient satisfaction. develops. Although the main cause normal again” and lose the “stigma” It also contains all the data necessary of failure of THA is aseptic loosen- of disability—were the most satis- for calculating the other standard ing, hip pain of other origin should fied (96%); those who wanted to hip scores. not be attributed to presumed loos- return to nonessential activities were ening. The diagnostic dilemma of least satisfied (75%). Burton et al2 the painful hip after a seemingly reported that only 55% of patients Dr. Robbins is Clinical and Research Fellow, well-fixed THA is becoming more had their expectations fully met by Division of Reconstructive Orthopaedics, common as more arthroplasties are THA. In addition, the extent of dis- University of British Columbia, Vancouver, performed. Therefore, practitioners ease and any comorbidities also can BC, Canada. Dr. Masri is Associate Professor who treat patients who have under- have a marked effect on functional and Head, Division of Reconstructive gone THA should appreciate the result and overall satisfaction—for Orthopaedics, University of British Columbia. Dr. Garbuz is Assistant Professor, Division of range of causes of hip pain and de- example, whether the primary con- Reconstructive Orthopaedics, University of velop a rational approach for inves- dition affects only the treated hip or British Columbia. Dr. Duncan is Professor tigation. both hips and whether other sys- and Chairman, Department of Orthopaedics, The level of postoperative patient temic disabilities exist. University of British Columbia. satisfaction depends partially on the The assessment of pain after THA patient’s expectations for the sur- is made more difficult because, Reprint requests: Dr. Masri, Third Floor, 910 West Tenth Avenue, Vancouver, BC V5Z 4E3, gery. It is necessary to ensure that although it is the primary reason for Canada. an unmet expectation is not at the a THA, pain is often underweighted root of the patient’s dissatisfaction by hip scores. Although the Harris Copyright 2002 by the American Academy of (eg, a persistent limp when a leg- hip score weights pain more heavily Orthopaedic Surgeons. length inequality has not been fully than does the Charnley score, one 86 Journal of the American Academy of Orthopaedic Surgeons Graham M. Robbins, MB, BS, FRCSOrth, et al Pain after THA in which the components appear to be solidly Is initial diagnosis correct? Initial relief of No Review history and examination fixed can have many causes. A symptoms by THA number of investigative steps may (eg, lumbar spine, pelvis, knee) be required to elicit the underlying Yes cause (Fig. 1). Radiologic evidence Both Aseptic Yes ESR and CRP of loosening negative loose THA History Either or both No A precise, in-depth history and positive physical examination of the patient Review history, examination, and plain are the most important steps in Aspiration Negative Reaspiration radiographs; do local anesthetic, assessing the painful THA. Even impingement, and fluoroscopy studies most cases of deep sepsis may be Diagnosis made Infected Positive correctly diagnosed from the history loose THA and physical examination alone.5 The time of onset of pain is of Yes No key importance. If the patient has Both negative, Treat ESR and CRP had no pain-free interval after weak history appropriately surgery and if the nature of the pain is different from that experienced Either or both positive preoperatively, a cause related or strong history directly to the surgery is implied, Negative, Positive Aspiration such as an acute infection, a large weak history hematoma, poor implant fixation, impingement, instability, or frac- Negative, ture. Persistence of the preoperative strong history pain suggests that the original diag- Aseptic fixed THA Infected 99Tc MDP nosis for which the THA was done Negative (possible minor bone scan should be questioned because an- fixed THA loosening) other source is likely. The site of the pain may give some Positive insight into its source. Groin and buttock pain are usually indicative of 111In leukocyte Positive acetabular cup or capsular abnormal- scan ities, while thigh pain or referred knee pain are often related to the Negative or femoral component. Localized pain equivocal over the greater trochanter is sugges- Sulphur tive of bursitis, and pain radiating Positive Negative colloid scan below the knee is usually of radicular or peripheral nerve origin. So-called start-up pain may represent early Figure 1 Algorithm for the investigation of painful total hip arthroplasty. THA = total hip arthroplasty; ESR = erythrocyte sedimentation rate; CRP = C-reactive protein level; loosening of one or both components. 99Tc MDP = technetium 99 methylene diphosphonate. Pain associated solely with activity may be related to an inflammatory condition, such as iliopsoas tendinitis or iliopectineal bursitis. End-of-stem In addition to the timing of the risk of deep prosthetic infection as a pain may be caused by a modulus onset and location of pain, a careful result of delayed wound healing mismatch between the implant stem history should be taken to identify or large hematoma formation. and the bone. Pain at night or at rest any precipitating events, such as Therefore, specific inquiry should be suggests infection or tumor but may trauma, systemic illness, or infection made about wound drainage, persis- also occur with aseptic loosening. elsewhere. There is an increased tent fever, prolonged antibiotic Vol 10, No 2, March/April 2002 87 Pain After Total Hip Arthroplasty administration, or delayed hospital Instability or impingement may a subset of patients has symptoms discharge. General factors that be a more subtle cause of intermit- of hip disease that cannot be easily increase the risk of infection include tent pain in the hip; they may be distinguished from spinal disease. previous hip surgery or infection, elicited by a particular position or Such symptoms can be particularly ongoing infection (eg, venous stasis motion of the lower extremity corre- perplexing after hip replacement. ulcers), immunosuppression, or neo- sponding to the position or activity In such cases, a diagnostic block of plastic disease. Moeckel et al6 did not during which the patient has experi- the hip joint with local anesthetic find increased incidence of deep sepsis enced pain. A complete examina- may help delineate the source of of hip arthroplasty in patients with tion of the ipsilateral knee and the the pain. In some cases, local irrita- diabetes mellitus, a finding contrary spine should include range of mo- tion of the sciatic nerve may cause to popular belief. In female patients, tion and assessment of nerves and thigh pain without spinal disease. a gynecologic history also should be tendons. When predicated, an ab- Pain also may be related to a obtained, particularly to elicit any dominal, pelvic, neurologic, or vas- metabolic condition, such as Paget’s relationship between the pain and cular assessment can be done to rule disease. This disease can be unilat- menses, which can occur with endo- out causes of referred pain from eral and affect the pelvis, lumbar metriosis and other conditions. an abdominal or pelvic mass, pe- spine, or femur. It may coexist with ripheral vascular disease, or spinal osteoarthritis of the hip but should stenosis. be apparent from plain radiographs Physical Examination and laboratory studies. Paget’s dis- ease can produce pain in the postop- Although the patient may complain Differential Diagnosis of erative period but should respond primarily of pain in the hip, referred the Painful THA well to medical management. pain from conditions unrelated to Primary bone tumors and metas- the arthroplasty must be ruled out. Referred Pain tases in either the pelvis (Fig. 2), The skin should be examined for When surgery does not provide lumbar spine, or femur can give rise inflammation, a sinus (healed or relief of symptoms, hip pathology to symptoms suggestive of a painful open), wound drainage, and any may not have been the cause of the THA.