Deep Venous Thrombosis and Pulmonary Embolus

Deep venous thrombosis (DVT) has been reported to be as high as 17.9% after arthroscopy of the knee. Some authors have stated that without proper screening, fatal pulmonary embolus (PE) may be as high as 1.3% of cases.¹ At an advanced arthroscopic knee course in August 2006, the audience was surveyed; 4 out of 40 knee arthroscopic surgeons had experienced a fatal PE in their practice, with an incidence in this small group of 10%.² Although arthroscopy of the knee is considered to be a “benign” procedure, one study noted at least one risk factor for DVT in 37% of patients undergoing routine knee arthroscopy.³ In 2004, Geerts and colleagues⁴ reported on multiple risk factors contributing to DVT and PE, including obesity, history of prior DVT, cancer, use of oral contraceptives, and increased age. Anderson and Spencer⁵ categorized the top 10 factors causing DVT and ranked them in terms of risk. Age older than 40 years was the most significant causative factor followed by obesity, prior history of DVT, cancer, bed rest longer than 5 days, major surgery, congestive heart failure, varicose veins, hip or lower extremity fracture, and estrogen treatment. They further noted that one or more risk factors increased the incidence of development of subclinical DVT or PE to 96.3%.

Eynon and associates⁶ were one of the first to suggest that all patients having routine knee arthroscopies should receive anticoagulant prophylaxis. One study has reported the incidence of DVT and/or PE when comparing a control group and a second group treated with low-molecular-weight heparin (LMWH) without any known risk factors to be as high as five times greater when diagnosed by ultrasound on days 7 and 10 postoperatively.⁷ Another study noted a 10 times greater incidence of DVT and/or PE after preoperative and postoperative treatment with LMWH when diagnosed with ultrasound at 12 and 31 days postoperatively.⁸ It is estimated that between 20% to 30% of calf thrombi propagate proximally to the popliteal and femoral veins, which have an increased chance of resulting in PE. Some have argued that pharmacologic DVT prophylaxis should be routinely prescribed to patients undergoing knee arthroscopy for that reason.^1,6 However, there are no agreed on recommendations in the literature about prophylaxis for arthroscopy of the knee, with or without prior history of DVT or PE.¹ We recommend that all those undergoing knee arthroscopy should be given acetylsalicylic acid (ASA) preoperatively and postoperatively for 4 weeks and that those with acquired, genetic, or hemostatic risk factors be placed on preoperative and postoperative warfarin (Coumadin) or LMWH for 3 to 4 weeks to reduce the possibility of PE or DVT.

Wrong-Site Surgery

Wrong-site surgery (WSS) accounts for approximately 2% of all orthopedic claims. However, 84% result in a mean court award to the plaintiff of $48,087. Most of these were knee arthroscopies. The Physician Insurer’s of North America recorded 331 WSS claims from 1985 to 1995, and 225 were against orthopedic surgeons.⁹ The incidence of WSS reported to the American Academy of Orthopaedic Surgeons (AAOS) between January 1995 and December 2003 were 17% wrong knee, 12% wrong person, and 10% wrong procedure. Interestingly, hospital-based ambulatory surgery centers had the highest incidence of errors, 53%. The three most important factors to prevent wrong-site surgery errors were preoperative patient identification, surgical site indelible marking, and the physician’s signature on the surgical site. When all three of these were done, there was a 0% failure rate. However, when only two of these three were done, there was a 12% incidence of failure.¹⁰ Additional analysis of the complications that occurred estimated that an orthopedic surgeon has a 25% chance of performing wrong-site surgery during his or her career and that WSS tends to increase with increasing age and increased caseloads.^9,11

In a survey presented at the AAOS in 2005, 1575 Arthroscopy Association of North America members reported an incidence of one WSS for every 26,581 arthroscopic procedures that were performed. The average age of the respondents was 48.2 years, with a practice mean of 15.8 years; 8.5% of respondents had performed wrong-site arthroscopy at least once during their careers. In this survey report, the risk of WSS increases with surgeon age, increasing years of practice, and increased surgical volume.¹² In Minnesota, in 2004, there were 22 adverse events reported—13 patients had the wrong body part operated on, in four cases the wrong patient was operated on, and in five cases the wrong procedure was performed. In 2005, in Minnesota, there were 26 adverse events—16 patients had the wrong body part operated on, in two cases the wrong patient was operated on, and in eight cases the wrong procedure was performed.¹³

Several requirements to reduce the risk of WSS significantly must be implemented in the hospital or ambulatory surgery center setting. Initially, the admitting nurse must identify the patient’s correct name preoperatively by verbally asking the patient and correlating this with the wristband. The surgeon should also check the patient’s name, either by directly asking the patient for his or her name and looking at the wristband. Second, the surgeon and patient should sign the site with an indelible marker within the operative site not covered by a drape. The patient should put “yes” on the operative knee and the surgeon should sign her or his initials directly over the operative site. Third, and finally, the circulating nurse must read the permit out loud and everyone in the operating room should acknowledge that this has been read, with the patient, procedure, and surgical site stated clearly. If these recommendations are followed 100% of the time, the incidence of wrong site surgery should be 0%.

Infection

The incidence of infection after knee arthroscopy has been reported to be from 0.04% to 0.42%.^14–16 Risk factors that have been reported to contribute to knee arthroscopy infections include intra-articular steroids given intraoperatively, increased surgical time, prior surgical procedures, chondroplasty, and soft tissue débridement.¹⁷ The diagnosis of infection can be difficult to make immediately postoperatively. Persistent pain and swelling after arthroscopy should have joint aspiration and culture despite the absence of fever, erythema, leukocytosis, or benign-appearing joint fluid. This diagnosis needs to be made immediately, if possible, and then treated with knee arthroscopy, lavage, and 2 to 6 weeks of intravenous antibiotics. Antibiotic prophylaxis in knee arthroscopy has been discussed and debated by several authors. Based on objective published literature, there is no statistical improvement in infection rates with preoperative IV antibiotics in routine arthroscopic surgery of the shoulder and knee.¹⁸ However, in today’s legal climate, others have argued that prophylactic antibiotics may be considered the standard of care in the local community and should be given regardless.¹⁹ Suggestions to avoid infections include operating efficiently and using antibiotic prophylaxis on immunocompromised patients. Furthermore, avoid the use of intra-articular steroids immediately prior, during, or after surgery. Finally, treat a swollen extremely painful knee postoperatively with immediate aspiration, cultures, and then aggressive arthroscopic débridement if the culture is positive, followed by IV antibiotics.

Nerve and Vascular Injury

Early reported complications of meniscal repair were common; these included saphenous neuropathy medially and peroneal neuropathy laterally secondary to injury and for nerve entrapment. Other complications associated with open meniscal repair, including both outside-in and inside-out techniques, were arthrofibrosis, severe postoperative effusion, and superficial and deep infection. Combined complication rates were reported as high as 18%.²⁰ Nerve and vascular injury have also been reported secondary to lateral meniscectomy and posterior cruciate and anterior cruciate ligament reconstruction. Despite the use of guide pins for the placement of the tibial guide pin (Fig. 5-1) during both anterior and posterior cruciate ligament reconstruction, popliteal artery injury (Fig. 5-2) continues to be of concern.²¹

FIGURE 5-2 Perforation of popliteal artery.

FIGURE 5-1 ACL guide with guide wire stop posteriorly.

Chondral Injury

Iatrogenic chondral injury is common during routine meniscectomy, especially in a tight medial compartment. In our experience, the presence of articular scuffing will result in significant degenerative changes within a few years and sometimes even in a few months. Note the significant chondral injury at 1 year postoperatively in a 45-year-old patient after a routine meniscectomy (Fig. 5-3). After 4 years, significant changes can occur from a routine meniscectomy (Fig. 5-4). Articular cartilage is about 2000 μm thick. A motorized shaver will shave up to 253 ± 78 μm and a radiofrequency (RF) thermal device will destroy up to 200 μm of articular cartilage. Some authors have argued that use of a RF device is more conservative than using a shaver.²² In a series of 256 patients who had partial medial meniscectomies at a mean age of 47 years, with an average follow-up of 18.5 years, 63% had undergone grade I or II surface changes,²³ yet 83% had good to excellent clinical results. In this series, age, gender, and meniscal tear type did not influence functional results.²⁴ Factors such as the larger size of meniscal resection and female gender resulted in the most consistent associations with more x-ray evidence of osteoarthritis (OA) across multiple studies.²⁵

FIGURE 5-3 Chondral injury subsequent to medial meniscectomy.

FIGURE 5-4 Result of chondral injury 4 years postmeniscectomy.

Chondral injury is also dependent on the type of tear that occurs. Complex and horizontal cleavage tears are highly associated with an increased incidence and severity of cartilage degeneration compared with other types of meniscal tears.²⁶ In one study, 45 lateral meniscal tears were associated with another articular surface procedure within 13 years postmeniscectomy secondary to the development of OA.^27,28 Suggestions to avoid chondral injury during meniscectomy include removing as little meniscal tissue as possible, but still leaving a stable meniscal remnant. Also, avoid damage to the articular surface with the meniscal resector tools.²⁹ Furthermore, consider doing a partial intra-articular release of a portion of the medial collateral ligament (MCL) when the knee is too tight in the medial compartment before proceeding with meniscal resection, either using a pie crust technique with a spinal needle (Fig. 5-5) or cutting through the anterior portion of the MCL several millimeters from the meniscal rim with a cutting cautery (Fig. 5-6). Inadequate meniscal resection during meniscectomy with a retained superior or inferior horizontal cleavage flap has been implicated in causing long-term chondral damage (Fig. 5-7). Finally, not recognizing malalignment of the extremity will result in increasing failure rates subsequent to meniscectomy, with progressive OA of the meniscectomized compartment.³⁰

FIGURE 5-5 Pie crust technique for release of MCL.

FIGURE 5-6 Electrocautery technique for partial release of anterior portion of MCL.

FIGURE 5-7 Inadequate meniscal resection.

Anterior Cruciate Ligament Surgery Complications

Anterior cruciate ligament (ACL) reconstruction complications are not uncommon with single- or double-bundled techniques. Anterior placement of the fixation device in the intercondylar notch (Fig. 5-8) or posterior placement of the fixation device in the tibia (Fig. 5-9) are not uncommon. Cyclops lesions (Fig. 5-10) are also common as well. There appears to be no advantage of supplemental aperture fixation with screws or bone cores to reduce tunnel widening. It has been argued that supplemental aperture fixation is associated with increased tunnel widening.³¹ Also, it has been suggested that leaving the stump of the ACL intact at the time of ACL surgery will reduce the incidence of cyclops lesions, because leaving the soft tissue in this area decreases the amount of debris that will surround the ACL in the tibia and reduce the amount of osteolysis that occurs next to the ACL.³² Delayed laxity, recurrent tearing, and graft failure are not uncommon. Furthermore, poor preparation of the hamstring graft so that it loosens during stress can occur. The allograft must be thawed prior to preparation to avoid stretching prior to implantation. Other complications include premature tearing of the hamstring graft during harvesting (Fig. 5-11) and posterior wall blowout (Fig. 5-12). Patellar fracture after patellar tendon bone (PTB) harvesting is becoming less common because of increased usage of allograft material but chronic anterior knee pain secondary to inadvertent infrapatellar nerve injury can occur subsequent to patellar tendon autograft harvesting. Double-bundle ACL reconstruction complications are primarily those of difficulty of placement of the double femoral tunnels. Also, fracture of the tunnel wall is not uncommon because it needs to be thin to place the tunnels in the anatomic position.³³

FIGURE 5-8 Anterior placement of femoral screw (arrow).

FIGURE 5-9 Posterior placement of tibial fixation device as noted on MRI scan (lateral view).

FIGURE 5-10 Cyclops lesion on AP MRI scan of tibia (AP view).

FIGURE 5-11 Premature hamstring resection caused by lack of release of adherent band.

(Courtesy of Dr. Don Johnson.)

FIGURE 5-12 Posterior wall blowout.

(Courtesy of Dr. Don Johnson.)

Biodegradable Implant Complications

Failed resorption of biodegradable implants has been reported with multiple designs. Meniscal arrows (Biofix; Bionx Implants, ConMed Linvatec, Pa) and Biostingers (ConMed Linvatec, Largo, Fla) have resulted in failure of repair with loosening and/or incomplete resorption at 5, 7, 9, and 13 months, resulting in persistent knee pain (Fig. 5-13). In all cases, the remnants of the biodegradable material were removed, synovectomies were performed, and all patients responded favorably. Several authors have described synovitis and chondral lesions up to 13 months postoperatively. On removal of implants and following synovectomy, patients ultimately did well. Chondral injury was present in all cases.^34–37 A case of the RapidLoc PLLA implant (DePuy Mitek, Raynham, Mass) loosening, resulting in chondral injury, was reported at 4 months postarthroscopy (Figs. 5-14 and 5-15). These patients most commonly present with mechanical symptoms at the time of device loosening.³⁸ The FAST-Fix meniscal repair system (Smith & Nephew, Andover, Mass) can cause a meniscal cyst at subsequent implantation prior to resorption of the device.³⁹ This was seen in one of the senior author’s (  JB) cases at 16 weeks postoperatively, with MRI confirming a meniscal cyst adjacent to a Fast-Fix meniscal repair device (Fig. 5-16).

FIGURE 5-13 Posterior penetration of meniscal arrow, resulting in soft tissue irritation (arrows).

(Courtesy of Dr. Alan Barber.)

FIGURE 5-14 Dislodged RapidLoc fixation device (DePuy Mitek, Raynham, Mass).

(Courtesy of Dr. Alan Barber.)

FIGURE 5-15 Femoral condylar injury secondary to RapidLoc device loosening.

(Courtesy of Dr. Alan Barber.)

FIGURE 5-16 Meniscal cyst development 16 weeks after meniscal repair with Fast-Fix device (Smith & Nephew, Andover, Mass).

Miscellaneous Complications

Miscellaneous complications include fluid extravasation as a result of arthroscopy pump or tubing failure. If the pump continues to run without an egress cannula in the joint, and the joint becomes taut with fluid, the pump should be immediately shut down or extravasation of fluid into the thigh (Fig. 5-17) can occur.⁴⁰ Chronic synovitis after routine arthroscopy of the knee (Fig. 5-18) has been reported to be from 2% to 3%. Care must be taken not to overlook a postoperative infection. Treatment is prolonged oral anti-inflammatories or intra-articular steroid injections.⁴¹

FIGURE 5-17 Fluid extravasation in left thigh caused by pump tubing failure.

FIGURE 5-18 Severe synovitis postarthroscopic meniscectomy.