Patient Considerations: Comorbidities and Optimization

Patient History

In general, the indications for a TKA include knee pain, mechanical instability, decreased range of motion secondary to pain, and the decreased ability to perform activities of daily living. Knee pain and the amount of knee pain during daily activities should be the primary consideration for TKA, with an improvement in function being a secondary consideration. Additionally, each insurance carrier may have a unique set of criteria that the patient must fulfill in the nonoperative setting before TKA. One should be wary of the patient who is considering a TKA mainly for improvements in range of motion or in the ability to perform a recreational event but who does not have marked pain with daily activities. The majority of patients will experience pain reduction after TKA with considerable improvement in knee function; however, an expectation of improved pain, but not necessarily completely resolved pain, should remain the main point of discussion with the patient in the preoperative period. Setting a preoperative expectation of improved pain relief, but possibly not complete resolution of pain, is important as many patients will still have some periods of discomfort that come and go postoperatively.

A description of the patient’s preoperative pain symptoms should be thoroughly recorded. This includes the severity of pain at rest and with activities such as stair use and the distance the patient is able to walk without pain. The use of preoperative narcotics or alternate analgesics, the use of an assistive device for ambulation, and pain that keeps the patient up at night or awakens them in the middle of the night are all important factors in determining the severity of a patient’s symptoms and whether a knee arthroplasty is a reasonable consideration. An accurate description of the changes in severity of the pain throughout daily activities can help the surgeon better understand provocative activities that cause pain. Severe pain and what activities provoke this severe pain should always be investigated thoroughly. In rare instances patients can be in constant and severe pain; additional sources of pain generation should be considered in those patients who have unrelenting and severe pain.

In addition to pain at rest the pain during specific activities should be evaluated. It is important to document what activities cause pain and what activities are unable to be performed because of pain. Identifying the activities the patient used to perform and the activities they would like to return to performing will guide preoperative expectation counseling. Delineation of pain during activities of daily living versus during sporting events or primarily recreational activities will help guide the preoperative discussion of pain relief. One of the most reliable indications for TKA is pain with simple daily activities that is interfering with quality of life. The expectation to return to normal daily activities is a reasonable one versus the expectation to return to high-level sporting performance that the patient may or may not be able to do after TKA. Symptoms that do not correlate with radiographic findings should be further evaluated, and caution should be considered when offering these patients the option of TKA.

A patient’s occupation should also be considered before performing a TKA. Patients whose occupation requires constant kneeling and climbing may not be well-suited for TKA. In this scenario counseling should be provided about the possibility of the patient not being able to return to the exact occupation or job description that they currently hold. The patient should also consider the option of job retraining or a less manually strenuous aspect of their current occupation, although many people under the age of 60 years will return to their previous occupation after TKA. The amount of time needed for postoperative recovery can be discussed at this time. A return to work 4 to 6 weeks postoperatively may be reasonable for patients who have a more sedentary job, whereas return to work at 8 to 12 weeks may be more realistic for patients who have strenuous jobs that allow for minimal breaks in the workday. This discussion will allow patients to plan their sick leave or time off from work with their employer. If the patient is near retirement age, they may elect to delay surgery until after retirement so as to not exhaust all sick leave and vacation time. Ultimately, the timeframe for return to work will be patient- and occupation-specific and variable based on the postoperative recovery process. Return to driving is another important consideration after TKA. Previous work suggests that reaction time to braking may return to normal around the 4- to 6-week postoperative time point, and this can be used as a guideline for resumption of driving.

Another important aspect of the patient’s history is their response to and frequency of intraarticular injections, physical therapy, bracing, and nonsteroidal analgesics. These nonoperative treatment modalities should be tried in most, if not all, patients before surgery. The length of pain relief obtained from intraarticular injections should be carefully documented. If a local anesthetic is included in the injection, the pain relief from the injection should be noted before the patient leaving the office. If marked pain relief is not obtained in the near immediate time frame after injection, alternate pain sources should be evaluated before consideration of TKA. Identifying which nonoperative treatment options have been successful and which have not is important to ensure that the surgeon does not recommend treatment options that have been tried and failed. This can frustrate the patient.

The use of preoperative narcotics must also be carefully considered. Preoperative narcotic use has been shown to decrease subjective postoperative outcomes, and these patients are more likely to continue narcotic use a year after surgery. Although literature suggests a decline in subjective outcomes with preoperative opioid use, it remains debatable whether or not to counsel patients about this to temper their postoperative expectations. Cessation of preoperative narcotic use is ideal and mandatory in some practices, but this may not be possible in all patients. One approach in counseling these patients is to clearly describe in layman’s terms the effects that chronic opioid use has on pain tolerance and perceived pain in the postoperative period in order to appropriately set postoperative expectations. The topic of opioid use is covered in more detail in the next chapter.

The patient’s medical history must be considered before surgery. Comorbidities that can be optimized should be identified. More specific recommendations on perioperative medical management will be discussed later in this book. It is important to understand the medical history when counseling patients on their perioperative risks of cardiac events, deep vein thromboses, unexpected pulmonary events, periprosthetic joint infections, anesthetic complications, and even death. Although perioperative outcomes after TKA have dramatically improved from the 1970s to 2020, the possibility of perioperative risks must be considered and thoroughly discussed with the patient during the preoperative discussion.

Physical Examination

The physical examination begins with an initial observation of the patient’s gait and their ability to transfer from chair to standing and to climb onto an examining table. The amount of pain and dysfunction observed during these activities can be helpful adjuncts to the oral history. Observation of a varus or valgus thrust, recurvatum or hyperflexibility, quadriceps inhibition, or a fixed flexion contracture can additionally give insight into the expected complexity of the case.

Routine assessment of passive and active range of motion, the ability to correct the deformity, crepitus, and peripheral circulation is important. In a varus knee tenderness along both the medial joint line and posterior lateral soft tissues is often observed because of the stretching of the lateral tissues as the varus deformity progresses. With the leg in full extension, an anterior to posterior pressure applied to the patella and palpation of the medial and lateral facets of the patella with medial and lateral patellar tilt maneuvers may elicit pain. This finding gives insight into the sensitivity of the patellofemoral joint, which may influence the surgical decision-making process.

Evaluation of the skin and any previous skin incisions that will influence the surgical approach should be documented. In general, the oldest incision should be used if it does not result in an undo strain on the surgical approach. Otherwise, the oldest and most laterally based incision should be used because of the main blood supply of the cutaneous tissues originating from the medial aspect of the limb. Careful examination of the foot and lower leg should also be performed. Findings of open ulcers, severe lymphedema, or chronic cellulitis need to be addressed prior to any elective TKA because of the increased risk of periprosthetic joint infection in patients who have these conditions. These conditions should be considered contraindications to surgery until resolved or optimized. Additionally, patients with decreased sensation in their feet, or a history of decreased sensation, without a known diagnosis of diabetes should be screened with a hemoglobin A1c test. These issues will be discussed further in subsequent chapters ( Chapter 2, Chapter 3 ).

A hip examination should always be performed because of the possibility of referred knee pain. Branches of the obturator nerve and femoral nerve innervate the anterior hip capsule. In patients who have hip arthritis or hip pathology this nerve can become inflamed and result in referred pain to the knee. Knee pain with range of motion of the hip and minimal knee pain when knee motion is isolated should alert the surgeon to the possibility of a referred pain phenomenon.

The overreaction of the patient to perceived pain and pain out of proportion to provocative maneuvers should carefully be evaluated for either a secondary gain purpose or alternate sources of pain. Hyperanalgesia of the skin or noted skin changes may represent a complex regional pain type syndrome that may be exacerbated by TKA. History of depression or anxiety noted on the oral history may correlate with an overly anxious patient during the physical examination. Patients who have pain out of proportion to radiographic and physical examination findings may have poor subjective satisfaction after knee arthroplasty surgery.