TKA for Posttraumatic Osteoarthritis Is More Complex and Needs More Surgical Resources

A New Concept of Using Femoral Condyles Surface for Femoral Component Alignment During Total Knee Arthroplasty: A Technical Note

Background

Orthopedic surgeons favor an intramedullary guiding system on the femoral component during total knee arthroplasty (TKA); nevertheless, improper positioning of the entry point affects the final alignment. We have designed a new femoral cutting system for TKA that uses the distal and posterior femoral condyles as reference points for the setting of the cutting system regardless of the femoral canal. This study aims to evaluate the outcomes of this new guiding system.

Methods

We enrolled a series of 75 consecutive knees undergoing TKA. The alpha, gamma, and hip-knee-ankle (HKA) angles were assessed three months postoperatively. Also, surgical time and intraoperative blood loss were recorded for all patients.

Results

Fifteen patients underwent TKA using the mechanical alignment (MA) strategy, and 60 underwent kinematically aligned (KA) TKA. Both groups showed normal coronal and sagittal alignment 3 months postoperatively. The mean intraoperative blood loss was 213.11 ± 52.73 ml, which was not different between the two groups (n.s.). The mean surgical time was 43.12 ± 11.62 min, which was significantly shorter in the KA-TKA (41.11 ± 3.77 min) than in the MA-TKA (49.34 ± 4.56 min) (P < 0.001).

Conclusion

Using the new guiding system with good femoral alignment, we introduced the easily palpable and available condylar surface as a new landmark for cutting the distal femur in TKA.

Level of Evidence

IV.

Increased complications rates and inferior patient reported outcomes following total knee arthroplasty due to post-traumatic osteoarthritis with previous fracture treatment: a systematic review

PURPOSE

This study aims to present the existing literature relating to patient-reported outcome measures (PROMs) and complications in patients undergoing total knee arthroplasty (TKA) due to posttraumatic osteoarthritis (PTOA) with prior fracture treatment around the knee compared with patients who underwent TKA because of primary osteoarthritis (OA).

METHODS

A systematic review was undertaken and synthesised in accordance with the PRISMA guidelines by searching existing literature in the following databases: PubMed, Scopus, Cochrane Library and EMBASE. A search string according to the PECO was used. After analysing 2781 studies, 18 studies (5729 PTOA patients/149,843 OA patients) were included for a final review. An analysis revealed that 12 (67%) were retrospective cohort studies, four (22%) were register studies and the remaining two (11%) were prospective cohort studies. The mean Critical Appraisal Skills Programme (CASP) score was 23.6 out of 28, signifying studies of moderate quality.

RESULTS

The most frequently reported outcome measure were postoperative complications, reported in all eighteen studies. Intraoperative complications were reported in ten (4165 PTOA/124.511 OA) and patient-reported outcome measures (PROMs) in six studies (210 PTOA/2768 OA). A total of nine different PROMs were evaluated. As far as PROMs were concerned, the scores were inferior for PTOA but did not differ statistically from OA, except for one study, which favoured the OA group. Across all studies, postoperative complications were higher in the PTOA group, reporting infections as the most common complication. Furthermore, a higher revision rate was reported in the PTOA group.

CONCLUSION

PROM analysis suggests that both patient groups benefit from a TKA in terms of functional outcome and pain relief, however, patient-reported outcomes could be inferior for PTOA patients. There is consistent evidence for increased complication rates following PTOA TKA. Patients undergoing TKA due to PTOA after fracture treatment should be informed about the risk for inferior results and refrain from comparing their knee function to patients with TKA after OA. Surgeons should be aware of the challenges that PTOA TKA poses.

LEVEL OF EVIDENCE

Level III.

Total knee arthroplasty in post-traumatic osteoarthritis is more challenging, but results in similar patient satisfaction - An analysis of 1646 cases

BACKGROUND

Patients with post-traumatic osteoarthritis (PTOA) present a variety of technical challenges to surgeons. Surgical parameters, complication rates and patient-reported outcomes (PROs) have been reported as detrimental in total knee arthroplasty (TKA) for PTOA. The purpose of this study was to compare these variables and satisfaction with the results of TKA in patients with post-traumatic osteoarthritis with a matched-pair cohort of primary osteoarthritis (POA).

METHODS

A registry-embedded prospective case-control study was performed. Of a total of 1646 TKAs, 155 were performed due to PTOA between 2012 and 2019. One-hundred and thirty-six could be one-to-one propensity score-matched to patients with POA undergoing primary TKA based on similar patient demographic variables. Outcomes investigated included operation time, estimated blood loss, types of implants, postoperative complications and PROs pre- and 1 year postoperatively as well as satisfaction with the results of surgery. Sub-cohort analysis was performed for patients with prior fracture and soft tissue trauma, respectively.

RESULTS

Surgical parameters were significantly different in disadvantages of PTOA: operation time (P < 0.001), estimated blood loss (P < 0.001), blood transfusions (P = 0.039), type of implants (P < 0.001). Manipulation under anaesthesia (MUA) was necessary more often in the PTOA fracture group (odds ratio 5.01, (95% confidence interval 1.04; 24.07). PRO demonstrated no substantial differences after 1 year. Satisfaction with the results of TKA was as equally high in all cohorts.

CONCLUSIONS

This study demonstrated that TKAs in patients with PTOA require higher surgical effort but can result in similar PROs and satisfaction compared to POA, regardless of the underlying trauma.

TKR after posttraumatic and primary knee osteoarthritis: a comparative study

Background

A few literatures reported that the outcomes of total knee replacement (TKR) in posttraumatic osteoarthritis (PTOA) were lower compared to TKR in primary osteoarthritis (primary OA). The study’s purpose was to compare the comorbidity and outcome of TKR among fracture PTOA, ligamentous PTOA, and primary OA. The secondary aim was to identify the effect of postoperatively lower limb mechanical axis on an 8-year survivorship after TKR between PTOA and primary OA.

Methods

Seven hundred sixteen patients with primary OA, 32 patients with PTOA (knee fracture subgroup), and 104 PTOA (knee ligamentous injury subgroup) were recruited. Demography, comorbidities, Charlson Comorbidity Index (CCI), operative parameters, mechanical axis, functional outcome assessed by WOMAC, and complications were compared among the three groups.

Results

PTOA group was significantly younger (p<0.0001) with a higher proportion of men (p=0.001) while the primary OA group had higher comorbidities than the PTOA group, including anticoagulant usage (p=0.0002), ASA class ≥3 (p<0.0001), number of diseases ≥ 4 (p<0.0001), and CCI (p<0.0001). Both the fracture PTOA group (p<0.0001) and ligamentous PTOA group (p = 0.009) had a significantly longer operative time than the primary OA group. The fracture PTOA group had significantly lower pain components and stiffness components than the primary OA group. There was no significant difference in the rate of an aligned group, outlier group, and an 8-year survivorship in both groups.

Conclusion

The outcome following TKR in the fracture PTOA was poorer compared to primary knee OA in the midterm follow-up. However, no difference was detected between the ligamentous PTOA and primary knee OA. The mechanical axis alignment within the neutral axis did not affect the 8-year survivorship after TKR in both groups.

Level of evidence

Level III; retrospective cohort study

Lingering risk: A meta-analysis of outcomes following primary total knee arthroplasty for patients with post-traumatic arthritis

BACKGROUND

Currently, no meta-analysis exists to elucidate the outcomes of primary total knee arthroplasty (TKA) in patients with post-traumatic arthritis (PTA). The primary aim of this meta-analysis was to compare revision and complication rates for patients with PTA versus osteoarthritis (OA).

METHODS

The following databases were used for searching existing literature (from their inception to October 2019): PubMed, Scopus, EMBASE, Cochrane Library, and Web of Science. The primary outcomes were the incidences of revision and complications, Secondary outcomes included operative time and patient-reported outcomes (PRO) scores.

RESULTS

Nine studies with a total of 6,783,990 patients were included. This study found that there was a statistically significant difference in the rates of superficial wound infection, periprosthetic infection, stiffness, wound complications, and revision, with these outcomes occurring more frequently in patients with PTA. However, PTA did not increase the risks for periprosthetic fracture, aseptic loosening or instability, and VTE. Moreover, PTA was associated with increased operative time, worse postoperative PRO scores, and similar changes in PRO scores.

CONCLUSIONS

This meta-analysis highlight the complexity of PTA and demonstrates increased risks of infection, wound complications, stiffness, and revision. Surgeons can use this information to help aid in counseling patients preoperatively.

Pathomechanisms of Posttraumatic Osteoarthritis: Chondrocyte Behavior and Fate in a Precarious Environment

Traumatic injuries of the knee joint result in a wide variety of pathomechanisms, which contribute to the development of so-called posttraumatic osteoarthritis (PTOA). These pathogenetic processes include oxidative stress, excessive expression of catabolic enzymes, release of damage-associated molecular patterns (DAMPs), and synovial inflammation. The present review focuses on the underlying pathomechanisms of PTOA and in particular the behavior and fate of the surviving chondrocytes, comprising chondrocyte metabolism, regulated cell death, and phenotypical changes comprising hypertrophy and senescence. Moreover, possible therapeutic strategies, such as chondroanabolic stimulation, anti-oxidative and anti-inflammatory treatment, as well as novel therapeutic targets are discussed.

[Gait analysis after total knee arthroplasty assisted by three-dimensional printing navigation template]

OBJECTIVE

To explore the gait trajectory characteristics of patients after total knee arthroplasty (TKA) assisted by three-dimensional (3D) printing navigation template.

METHODS

Twenty female patients (20 knees) with knee osteoarthritis who were treated with TKA assisted by 3D printing navigation template between February 2017 and February 2018 were selected as the 3D printing group. The patients were 50-69 years old, with an average age of 57.2 years. The disease duration was 4-7 years, with an average of 5.6 years. The osteoarthritis was classified as Kellgren-Lawrence Ⅲ level in 5 cases and Ⅳ level in 15 cases. The preoperative hip-knee-ankle angle (HKA) was (170.8±5.6)°. All patients were varus deformity. According to age and affected side, 20 healthy female volunteers were selected as the control group. The volunteers were 51-70 years old, with an average age of 56.7 years. Preoperative HKA was (178.8±0.6)°. There was significant difference in HKA between the two groups ( P>0.05). The HKA, Western Ontario and McMaster University Osteoarthritis Index (WOMAC), and visual analogue scale (VAS) scores of the 3D printing group before and after operation were compared. At 6 months after operation, the gait trajectory characteristics of 3D printing group and control group were analyzed by Vicon gait capture system. The kinematics parameters included velocity, cadence, stride length, maximum knee flexion angle (stance), minimum knee flexion angle (stance), maximum knee flexion angle (swing), mean hip rotation angle (stance), mean ankle rotation angle (stance).

RESULTS

The incisions of 3D printing group healed by first intention, with no complications. All patients were followed up 7-12 months (mean, 9.0 months). The WOMAC and VAS scores at 6 months after operation were significant lower than those before operation ( P<0.05). The HKA was (178.8±0.8)° at 4 weeks after operation and the difference was significant when compared with that before operation ( t=39.203, P=0.000). The position of the prosthesis was good. The femoral posterior condyle osteotomy line, surgical transepicondylar axis, and patella transverse line were parallel, varus deformity was corrected, and lower limb alignment was restored to neutral position. Gait analysis at 6 months after operation showed that the differences in all kinematics parameters between the two groups were significant ( P<0.05).

CONCLUSION

Assisted by 3D printing navigation template, TKA can alleviate pain symptoms and correct deformity, with satisfactory early effectiveness. Compared with healthy people, the early postoperative gait of the patients were characterized by decreasing velocity, cadence, stride length, knee flexion range, and increasing compensatory hip and ankle rotation range.

Perioperative combined administration of tranexamic acid and dexamethasone in total knee arthroplasty-benefit versus harm?

BACKGROUND

The purpose of this study was to investigate the benefits and harm of combined administration of tranexamic acid (TXA) and dexamethasone (Dexa) in total knee arthroplasty (TKA).

METHODS

A total of 88 consecutive patients undergoing TKA for knee osteoarthritis were stratified in 2 groups. All surgeries were performed under general anesthesia. Brief, patients in the TXA + Dexa group (n = 45) received 10 mg Dexa just after the anesthesia, and repeated at 24 hours after the surgery; and patients in the TXA group (n = 43) received 2 ml of normal saline solution at the same time. The measured outcomes were the C-reactive protein (CRP) and interleukin-6 (IL-6) from preoperatively to postoperatively, and postoperative nausea and vomiting (PONV), fatigue, range of motion (ROM), length of stay (LOS), and the analgesic and antiemetic rescue consumption RESULTS:: The level of CRP and IL-6 in the TXA + Dexa group were lower than that in the TXA group at 24 hours (P < .001, P < .001), 48 hours (P < .001, P < .001), and 72 hours (P < .001, P < .001) after the surgery. The pain scores in the TXA + Dexa group were lower during walking at 24 hours (P < .001), 48 hours (P < .001), and 72 hours (P < .001) and at rest at 24 hours (P = .022) after the surgery. Patients in the TXA + Dexa group had a lower nausea score, the incidence of PONV, fatigue, and the analgesic and antiemetic rescue consumption, and had a greater ROM than that in the TXA group. No significant differences were found in LOS and complications.

CONCLUSION

The combined administration of TXA + Dexa significantly reduced the level of postoperative CRP and IL-6, relieve postoperative pain, ameliorate the incidence of POVN, provide additional analgesic and antiemetic effects, reduce postoperative fatigue, and improve ROM, without increasing the risk of complications in primary TKA.

Conversion Total Knee Arthroplasty: A Distinct Surgical Procedure With Increased Resource Utilization

BACKGROUND

Current Procedural Terminology coding currently makes no distinction between primary total knee arthroplasty (TKA) and conversion TKA, in which periarticular hardware components must be removed prior to or during TKA. We hypothesize that conversion TKA will carry increased operative time, blood loss, postoperative complications, and 90-day emergency department/readmission rate compared to primary TKA.

METHODS

Patients undergoing conversion TKA from 2005 to 2017 were identified from an institutional database and matched to primary TKA patients by age, gender, American Society of Anesthesiologists score, body mass index, and procedure date (±1 year). Intraoperative data and 90-day postoperative complications were compared between groups.

RESULTS

One hundred nine conversion TKA patients with periarticular hardware were removed prior to (n = 51) or during (n = 58) TKA and 109 primary TKA control patients were included. Conversion TKA was associated with increased tourniquet time (91 vs 71 minutes, P < .001), operative time (147 vs 113 minutes, P < .001), blood loss (225 vs 176 mL, P = .010), 90-day readmissions (14.6% vs 4.2%, P = .020), wound complication (5.6% vs 0.0%, P = .025), periprosthetic joint infection (7.9% vs 0.0%, P = .005), irrigation/debridement (9.0% vs 1.1%, P = .016), and a trend toward increased mechanical complication (6.7% vs 1.1%, P = .058). Timing of hardware removal did not affect intraoperative or postoperative outcomes.

CONCLUSION

Conversion TKA is associated with higher operative time, blood loss, readmission rate, and postoperative complications compared to primary TKA. Without a proper billing code and appropriate reimbursement level to match the expected operative and postacute resource utilization by these cases, physicians may be disincentivized to perform these operations.

Medial Open-wedge Osteotomy with Double-plate Fixation for Varus Malunion of the Distal Femur

Objective

To present our clinical experience of treating varus malunion of the distal femur through a medial open‐wedge osteotomy with double‐plate fixation.

Methods

A prospective cohort study was performed. From January 2005 to February 2015, 15 consecutive patients with varus malunion following distal femur fractures were surgically treated at a single level I trauma center. The coronal and sagittal deformity were corrected by a medial open‐wedge osteotomy of the distal femur. A medial buttress plate was used to maintain the realignment. A lateral locking plate was additionally used as a protection plate. The mean age of patients at the time of the surgery was 35.5 years (range, 22–58 years). The radiographical evaluation included the mechanical femorotibial angle, the mechanical lateral distal femoral angle, the anatomic posterior distal femoral angle, and the leg length discrepancy. Clinical outcome evaluation consisted of the range of motion (ROM) and Hospital for Special Surgery (HSS) score.

Results

Mean follow‐up was 7.4 years (range, 4–11.5 years). Varus and flexion malalignment and limb discrepancy were adequately corrected in all patients. The mechanical femorotibial angle, the mechanical lateral distal femoral angle, and the anatomic posterior distal femoral angle were restored from 17.5° (range, 13°–25°) to 2.3° (range, − 2°–7°), 102.3° (range, 95°–112°) to 85.2° (range, 81°–92°), and 77.1° (range, 65°–87°) to 82.7° (range, 76°–88°), respectively. The leg length discrepancy was diminished from 3.4 cm (range, 2.4–4.5 cm) to 0.8 cm (range, 0–1.7 cm). The average bone healing time was 4.1 months (range, 2.5–6 months). The average ROM of the affected knees at 24‐month follow‐up was 3.4°–112.55°. The score of HSS at 4‐years follow‐up was 76.1 (range, 64–88). No internal fixation failure or secondary operation was noted until the last follow‐up.

Conclusion

Medial open‐wedge osteotomy can adequately correct the posttraumatic varus malunion of the distal femur. With fixation of the double plate, non‐displaced bone healing and good functional outcome are expected.

Preoperative Diagnosis Can Predict Conversion Total Knee Arthroplasty Outcomes

BACKGROUND

Compared to total knee arthroplasty (TKA) for primary osteoarthritis, conversion TKAs in the post-traumatic setting are associated with increased operative times, infection rates, and readmissions. We aim at determining how post-traumatic osteoarthritis and previous knee surgery influence postoperative outcomes in conversion TKA.

METHODS

Seventy-two conversion TKA procedures with prior knee trauma at a single institution between April 2012 and 2016 were examined. Twenty-seven (37.5%) cases had a preoperative site-specific diagnosis such as fracture of the proximal tibia, distal femur, or patella whereas 45 (62.5%) cases had a preoperative diagnosis of significant soft-tissue trauma. These 2 groups were compared in terms of total implant cost, length of stay, complications, and readmission and reoperation rates. A subanalysis was conducted to evaluate the effects of previous knee surgery on surgical outcomes.

RESULTS

The postfracture TKA cohort suffered significantly higher early surgical site complications (22% vs 4.4%, P = .02) and 90-day readmissions (14.8% vs 2.2%, P = .042) compared to the soft-tissue trauma cohort. Operative time, total implant costs, length of stay, medical complications, 30-day readmissions, and 90-day reoperation rates did not significantly differ. It was also found that patients with multiple prior knee surgeries compared to one prior knee surgery are younger (53.0 vs 63.1, P = .003), healthier, and receive significantly more expensive implants (1.72 vs 1.07, P = .026). In addition, patients with previous open reduction internal fixations experience more surgical site complications than patients with previous arthroscopies (31% vs 3.3%, P = .042).

CONCLUSION

Patients with previous site-specific fracture are more likely to experience surgical site complications and 90-day readmissions after conversion TKA than patients with previous soft-tissue knee trauma. Multiple previous knee surgeries appear to serve as an independent factor in the selection of costlier implants irrespective of preoperative diagnosis.